Aerobic capacity of chilean adults and elderly: proposal of classification by regional percentiles / Capacidade aeróbia de adultos e idosos chilenos: proposta de classificação por percentis regionais / Capacidad aeróbica de adultos y ancianos chilenos: propuesta de clasificación por percentiles regionales

ABSTRACT Introduction Aerobic fitness is an important predictor that contributes to the preservation of functional independence during the aging process. Its measurement represents a fundamental tool in the identification of multiple health problems. Objective To compare the aerobic capacity of adults and elderly subjects through international studies and to develop percentiles by age group using the LMS method. Methods A cross-sectional descriptive study was conducted with 1146 subjects (437 men and 709 women). The age group of the sample ranged from 50 to 84 years. The subjects evaluated came from the physical activity programs offered by the National Sports Institute (IND) and by the city council of Talca (Chile). Body mass, stature, oxygen saturation (SatO2), six-minute walk test, and systolic and diastolic blood pressure were assessed. Body Mass Index (BMI) was calculated for both sexes. The LMS method was used to propose the percent distribution. Results Aerobic capacity decreases with age (28.5% for men and 29.9% for women). There was a negative relationship between age and the six-minute walk test (men r = -0.13 and women r = -0.39). There was a discrepancy between the elderly subjects in the current study and those from international studies. The normative data for the classification of aerobic fitness were expressed in percentiles (p3, p5, p10, p15, p25, p50, p75, p85, p90, p95 and p97). Conclusion The aerobic performance of elderly subjects diminishes as they age; in addition, the current results differ from international studies, which motivated the development of percentiles to classify aerobic fitness in everyday situations, especially in places with few resources and particularly where field tests are considered a priority for large-scale physical evaluation. Level of evidence II; Diagnostic studies - investigation of diagnostic test.

RESUMO Introdução A aptidão aeróbia é importante preditor que contribui com a preservação da independência funcional à medida que se envelhece. Sua mensuração transforma-se em ferramenta fundamental na identificação de múltiplos problemas de saúde. Objetivo Comparar a capacidade aeróbia de adultos e idosos com estudos internacionais e desenvolver percentis por faixas etárias, utilizando o método LMS. Métodos Elaborou-se um estudo descritivo transversal com 1.146 sujeitos (437 homens e 709 mulheres). A faixa etária da amostra variou de 50 a 84 anos. Os sujeitos avaliados eram oriundos dos programas de atividade física oferecidos pelo Instituto Nacional de Desporto (IND) e pela prefeitura de Talca (Chile). Avaliaram-se massa corporal, estatura, saturação de oxigênio (SatO2), teste de caminhada de 6 minutos e pressão arterial diastólica e sistólica. Calculou-se o índice de massa corporal (IMC) para ambos os sexos. Utilizou-se o método LMS para propor a distribuição percentílica. Resultados A capacidade aeróbia diminui com o decorrer da idade (28,5% para os homens e 29,9% para as mulheres). Houve relação negativa entre a idade e o teste de caminhada de 6 minutos (homens: r = -0,13; mulheres: r = -0,39). Observou-se discrepância entre os idosos do presente estudo com os de estudos internacionais. Os dados normativos para a classificação da aptidão aeróbia foram expressos em percentis (p3, p5, p10, p15, p25, p50, p75, p85, p90, p95 y p97). Conclusão Os idosos diminuem o desempenho aeróbio conforme a idade avança. Os presentes resultados diferem dos estudos internacionais, o que motivou o desenvolvimento dos percentis para classificar a aptidão aeróbia em situações cotidianas, especialmente em locais com poucos recursos e principalmente onde os testes de campo são considerados prioritários para avaliação física em larga escala. Nível de evidência II; Estudos diagnóstico - investigação de teste diagnóstico.

RESUMEN Introducción La aptitud aeróbica es un importante predictor que contribuye con la preservación de la independencia funcional a medida que se envejece. Su medición se transforma en una herramienta fundamental en la identificación de múltiples problemas de salud. Objetivo Comparar la capacidad aeróbica de adultos y ancianos con estudios internacionales y desarrollar percentiles por grupos de edad utilizando el método LMS. Métodos Se elaboró un estudio descriptivo transversal con 1146 sujetos (437 hombres y 709 mujeres). El grupo de edad de la muestra varió de 50 a 84 años. Los sujetos evaluados eran oriundos de los programas de actividad física ofrecidos por el Instituto Nacional de Deporte (IND) y por la Municipalidad de Talca (Chile). Se evaluaron masa corporal, estatura, saturación de oxígeno (SatO2), test de seis minutos de caminata y presión arterial diastólica y sistólica. Se calculó el índice de masa corporal (IMC) para ambos sexos. Se usó el método LMS para proponer la distribución de percentil. Resultados La capacidad aeróbica disminuye con el transcurso de la edad (28,5% para los hombres y 29,9% para las mujeres). Hubo relación negativa entre la edad y el test de caminata de seis minutos (hombres r= -0,13 y mujeres r= -0,39). Se observó discrepancia entre los ancianos del presente estudio con los de estudios internacionales. Los datos normativos para la clasificación de la aptitud aeróbica fueron expresados en percentiles (p3, p5, p10, p15, p25, p50, p75, p85, p90, p95 y p97). Conclusión Los ancianos disminuyen el rendimiento aeróbico conforme avanza la edad. Los presentes resultados difieren de los estudios internacionales, lo que motivó el desarrollo de los percentiles para clasificar la aptitud aeróbica en situaciones cotidianas, especialmente en locales con pocos recursos y principalmente donde los tests de campo son considerados prioritarios para la evaluación física a larga escala. Nivel de Evidencia II; Estudios diagnóstico-investigación de test diagnóstico.

Learning histology through game-based learning supported by mobile technology / Enseñanza de la histología a través del aprendizaje basado en juegos apoyado por tecnología móvil

Digital game-based learning and the testing effect have been shown to be effective in improving learning. The use of screens offers the opportunity to test innovative learning strategies in the classroom. Here, we report the impact of implementing a game and testing effect-based learning tool in a histology course. Seventy nine students participated in the study (mean age 19.5 years, 65 % female). The students observed a slide-based class and then participated in a game, answering questions about key concepts, using their smartphones. Two surveys, asking about aspects related to perceptions/motivations and use of mobile technologies, were applied. The game allowed for immediate feedback, revealing student performance in every evaluated concept, and allowed teachers to give corrections after detecting conceptual mistakes. Students perceived the methodology as fun, interesting, interactive and attractive. Moreover, 96 % of students participated and enjoyed the game and, among them, all agreed to use the methodology again. In parallel, about 87 % of students use mobile technology to study and 97 % to find academic information, frequently. The results indicate that the vast majority of students use mobile technology to study and positively perceive the game-based strategy. Strategies allowing fast feedback and dynamic relationships in the classroom could potentially improve significant learning on concept acquisition.

El aprendizaje basado en juegos digitales y pruebas han demostrado ser efectivos en el mejoramiento del aprendizaje. El uso de pantallas ofrece la oportunidad de probar estrategias de aprendizaje innovadoras en el aula. En este estudio se presenta el impacto de la implementación de una herramienta de aprendizaje basada en juegos y pruebas aplicadas en un curso de histología. Setenta y nueve estudiantes participaron en el estudio (edad promedio 19,5 años, 65 % mujeres). Los estudiantes observaron una clase basada en diapositivas y luego participaron en un juego, respondiendo preguntas sobre conceptos clave, utilizando sus teléfonos inteligentes. Se aplicaron dos encuestas, preguntando sobre aspectos relacionados con las percepciones/motivaciones y el uso de tecnologías móviles. El juego permitió una retroalimentación inmediata, revelando el desempeño de los estudiantes en cada concepto evaluado, y permitió a los profesores dar correcciones cuando se detectaron errores conceptuales. Los estudiantes percibieron la metodología como divertida, interesante, interactiva y atractiva. Además, el 96 % de los estudiantes participaron y disfrutaron del juego y, de ellos, todos relataron la intención de utilizar la metodología nuevamente. En paralelo, 87 % de los estudiantes utilizan la tecnología móvil para estudiar y el 97 % para encontrar información académica, frecuentemente. Los resultados indican que la gran mayoría de los estudiantes usa tecnología móvil para estudiar y perciben positivamente la estrategia basada en juego. Las estrategias que permiten retroalimentación rápida y relaciones dinámicas en el aula podrían potencialmente mejorar el aprendizaje significativo en la adquisición de conceptos.

Imogolite Synthetized in Presence of As(III) Induces Low Cell Toxicity and Hemolysis, in Vitro, Potential Stabilization of Arsenite Present in Aqueous Systems.

Imogolite is a nanotubular aluminosilicate that has low toxicity in biological systems and due to its morphological and surface properties has a growing interest in environmental applications and biomedical areas. Its synthesis is highly sensitive to the presence of other ions, being able to inhibit or retard the process of imogolite formation, which could change the cytotoxic response of this substrate, something scarcely reported in the literature. In this context, the presence of arsenite during the synthesis of imogolite caused significant changes in the dimensions and surface behavior of these nanotubes. Cell viability was evaluated on EA.hy926 and HepG2 cells by (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay at 24 h. Meanwhile, the potential effects on human red blood cells, namely, hemolysis and morphological changes, were determined at 0 and 24 h. The range of % As tested of the nanotube showed cell toxicity similar to the control condition. Similarly, the As-based nanotubes induced hemolysis similar to controls and slight morphological changes of red blood cells at 0 and 24 h of exposition. These results indicate that As-based imogolite-like nanotubes are not toxic nor hemolytic and can be potentially used in processes like water purification.

αVß3 Integrin regulates astrocyte reactivity.

BACKGROUND: Neuroinflammation involves cytokine release, astrocyte reactivity and migration. Neuronal Thy-1 promotes DITNC1 astrocyte migration by engaging αVß3 Integrin and Syndecan-4. Primary astrocytes express low levels of these receptors and are unresponsive to Thy-1; thus, inflammation and astrocyte reactivity might be necessary for Thy-1-induced responses. METHODS: Wild-type rat astrocytes (TNF-activated) or from human SOD1G93A transgenic mice (a neurodegenerative disease model) were used to evaluate cell migration, Thy-1 receptor levels, signaling molecules, and reactivity markers. RESULTS: Thy-1 induced astrocyte migration only after TNF priming. Increased expression of αVß3 Integrin, Syndecan-4, P2X7R, Pannexin-1, Connexin-43, GFAP, and iNOS were observed in TNF-treated astrocytes. Silencing of ß3 Integrin prior to TNF treatment prevented Thy-1-induced migration, while ß3 Integrin over-expression was sufficient to induce astrocyte reactivity and allow Thy-1-induced migration. Finally, hSOD1G93A astrocytes behave as TNF-treated astrocytes since they were reactive and responsive to Thy-1. CONCLUSIONS: Therefore, inflammation induces expression of αVß3 Integrin and other proteins, astrocyte reactivity, and Thy-1 responsiveness. Importantly, ectopic control of ß3 Integrin levels modulates these responses regardless of inflammation.

The [Mo6Cl14]2- Cluster is Biologically Secure and Has Anti-Rotavirus Activity In Vitro.

The molybdenum cluster [Mo6Cl14]2- is a fluorescent component with potential for use in cell labelling and pharmacology. Biological safety and antiviral properties of the cluster are as yet unknown. Here, we show the effect of acute exposition of human cells and red blood cells to the molybdenum cluster and its interaction with proteins and antiviral activity in vitro. We measured cell viability of HepG2 and EA.hy926 cell lines exposed to increasing concentrations of the cluster (0.1 to 250 µM), by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. Hemolysis and morphological alterations of red blood cells, obtained from healthy donors, exposed to the cluster (10 to 200 µM) at 37 °C were analyzed. Furthermore, quenching of tryptophan residues of albumin was performed. Finally, plaque formation by rotavirus SA11 in MA104 cells treated with the cluster (100 to 300 µM) were analyzed. We found that all doses of the cluster showed similar cell viability, hemolysis, and morphology values, compared to control. Quenching of tryptophan residues of albumin suggests a protein-cluster complex formation. Finally, the cluster showed antiviral activity at 300 µM. These results indicate that the cluster [Mo6Cl14]2- could be intravenously administered in animals at therapeutic doses for further in vivo studies and might be studied as an antiviral agent.

Models of progressive neurological dysfunction originating early in life.

It is now well established that many of society's most devastating and costly neurological diseases and disorders arise from trauma at, or shortly after birth. In some cases deficits are seen in childhood and in others they are substantially delayed; arising in adolescence or young adulthood. In either case the initial insult initiates a metabolic and/or neurodegenerative cascade that proceeds, often undetected, for a considerable period of time before diagnosable symptoms appear. This affords a potential for detecting and slowing or arresting degenerative and/or malfunctioning processes prior to the appearance of symptoms, but requires an understanding of the mechanisms involved in the progressive dysfunction that characterizes the disease progression process. While numerous preclinical models of end-stage symptoms of neurological disease are established, animal models of progressive neurological dysfunction have received comparatively less attention. This review attempts to introduce the concept of modelling progressive dysfunction in animals and provides descriptions of the current status of several representative examples of models that have been developed and partially characterized for understanding diseases of the brain that arise either at or near the time of birth in rodents. It is our belief that such models are essential to understanding the underlying mechanisms responsible for progressive neurological dysfunction and hold the potential for identifying targets for early detection and presymptomatic therapy of these conditions.

The cluster [Re6Se8I6]3- induces low hemolysis of human erythrocytes in vitro: protective effect of albumin.

The cluster Re6Se8I63- has been shown to induce preferential cell death of a hepatic carcinoma cell line, thus becoming a promising anti-cancer drug. Whether this cluster induces acute hemolysis or if it interacts with albumin remains unclear. The effect of acute exposure of human red blood cells to different concentrations of the cluster with and without albumin is described. Red blood cells from healthy donors were isolated, diluted at 1% hematocrit and exposed to the cluster (25-150 µM) at 37 °C, under agitation. Hemolysis and morphology were analyzed at 1 and 24 h. The potential protection of 0.1% albumin was also evaluated. Exposition to therapeutic doses of the cluster did not induce acute hemolysis. Similar results were observed following 24 h of exposition, and albumin slightly reduced hemolysis levels. Furthermore, the cluster induced alteration in the morphology of red blood cells, and this was prevented by albumin. Together, these results indicate that the cluster Re6Se8I63- is not a hemolytic component and induces moderate morphological alterations of red blood cells at high doses, which are prevented by co-incubation with albumin. In conclusion, the cluster Re6Se8I63- could be intravenously administered in animals at therapeutic doses for in vivo studies.

Perinatal asphyxia: CNS development and deficits with delayed onset.

Perinatal asphyxia constitutes a prototype of obstetric complications occurring when pulmonary oxygenation is delayed or interrupted. The primary insult relates to the duration of the period lacking oxygenation, leading to death if not re-established. Re-oxygenation leads to a secondary insult, related to a cascade of biochemical events required for restoring proper function. Perinatal asphyxia interferes with neonatal development, resulting in long-term deficits associated to mental and neurological diseases with delayed clinical onset, by mechanisms not yet clarified. In the experimental scenario, the effects observed long after perinatal asphyxia have been explained by overexpression of sentinel proteins, such as poly(ADP-ribose) polymerase-1 (PARP-1), competing for NAD(+) during re-oxygenation, leading to the idea that sentinel protein inhibition constitutes a suitable therapeutic strategy. Asphyxia induces transcriptional activation of pro-inflammatory factors, in tandem with PARP-1 overactivation, and pharmacologically induced PARP-1 inhibition also down-regulates the expression of proinflammatory cytokines. Nicotinamide has been proposed as a suitable PARP-1 inhibitor. Its effect has been studied in an experimental model of global hypoxia in rats. In that model, the insult is induced by immersing rat fetus into a water bath for various periods of time. Following asphyxia, the pups are delivered, treated, and nursed by surrogate dams, pending further experiments. Nicotinamide rapidly distributes into the brain following systemic administration, reaching steady state concentrations sufficient to inhibit PARP-1 activity for several hours, preventing several of the long-term consequences of perinatal asphyxia, supporting the idea that nicotinamide constitutes a lead for exploring compounds with similar or better pharmacological profiles.

Pathophysiology of perinatal asphyxia: can we predict and improve individual outcomes?

Perinatal asphyxia occurs still with great incidence whenever delivery is prolonged, despite improvements in perinatal care. After asphyxia, infants can suffer from short- to long-term neurological sequelae, their severity depend upon the extent of the insult, the metabolic imbalance during the re-oxygenation period and the developmental state of the affected regions. Significant progresses in understanding of perinatal asphyxia pathophysiology have achieved. However, predictive diagnostics and personalised therapeutic interventions are still under initial development. Now the emphasis is on early non-invasive diagnosis approach, as well as, in identifying new therapeutic targets to improve individual outcomes. In this review we discuss (i) specific biomarkers for early prediction of perinatal asphyxia outcome; (ii) short and long term sequelae; (iii) neurocircuitries involved; (iv) molecular pathways; (v) neuroinflammation systems; (vi) endogenous brain rescue systems, including activation of sentinel proteins and neurogenesis; and (vii) therapeutic targets for preventing or mitigating the effects produced by asphyxia.