Relationships among motor coordination, body mass index and physical activity in adolescents with different weight status / Relaciones entre la coordinación motora, índice de masa corporal y la actividad física en adolescentes con diferentes estados de peso corporal

Purpose: To analyze the influence of physical activity level on associations between motor coordination and body mass index (BMI) in normal weight, overweight and obese adolescents. Method: Thirty nine adolescents (13 normal weight, 13 overweight and 13 obese) aged 12-14 years old, participated in this study. The Physical Activity Questionnaire for Older Children (PAQ-C) and Körperkoordinationtest für kinder (KTK) tools were used in order to assess the levels of physical activity and motor coordination, respectively. Bivariate and partial correlations were used to analyze the interrelationships among motor coordination, BMI and physical activity. The analysis of covariance test was used in order to compare the levels of motor coordination among normal weight, overweight and obese adolescents, considering the physical activity level as a covariate. Results: Moderate negative correlations (p<0.05) were found between motor coordination and BMI in the sample as a whole, normal weight and obese groups. However, when controlled for physical activity levels, it was not observed a significant co-rrelation in the normal weight group. Motor coordination and BMI were not significantly correlated in overweight adolescents with and without controlling for physical activity levels. Furthermore, motor coordination level demonstrated a trend to be lower in overweight and obese adolescents. Conclusion: Physical activity level influenced the association between motor coordination and BMI in normal weight adolescents, but not in overweight and obese. The negative effect of excess body mass on motor coordination level may overlap the possible influence that physical activity level exerts on the association between motor coordination and BMI in overweight and obese adolescents

Objetivo: Analizar la influencia del nivel de actividad física en las asociaciones entre la coordinación motora y el índice de masa corporal (IMC) en adolescentes de peso normal, con sobrepeso y obesos. Método: Treinta y nueve adolescentes (13 con peso normal, 13 con sobrepeso y 13 obesos) con edades comprendidas entre 12 y 14 años participaron en este estudio. Las herramientas Physical Activity Questionnaire for Older Children (PAQ-C) y Körperkoordinationtest für kinder (KTK) se usaron para evaluar los niveles de actividad física y coordinación motriz, respecti-vamente. Se usaron correlaciones bivariadas y parciales para analizar las interrelaciones entre la coordinación motora, el IMC y la actividad física. El análisis de covarianza se utilizó para comparar los niveles de coordinación motora entre los adolescentes de peso normal, con sobrepeso y obesos, considerando el nivel de actividad física como una covariable. Resultados: se encontraron correlaciones negativas y moderadas (p <0.05) entre la coordinación motora y el IMC en la muestra como un todo, en los adolescentes con peso normal y obesos. Sin embargo, cuando se controlan los niveles de actividad física, no se observó una correlación significativa en el grupo de peso normal. La coordinación motora y el IMC no se correlacionaron significativamente en adolescentes con sobrepeso con y sin control de los niveles de actividad física. Además, el nivel de coordinación motora demostró una tendencia a ser menor en adolescentes con sobrepeso y obesos. Conclusión: El nivel de actividad física influyó en la asociación entre la coordinación motora y el IMC en adolescentes de peso normal, pero no en adolescentes con sobrepeso y obesos. El efecto negativo del exceso de masa corporal en el nivel de coordinación motora puede superponerse a la posible influencia que ejerce el nivel de actividad física en la asociación entre la coordinación motora y el IMC en los adolescentes con sobrepeso y obesos

The effect of one year of unstructured table tennis participation on motor coordination level among young recreational players / El efecto de un año de la participación no estructurada del tenis de mesa en el nivel de coordinación motora entre los jóvenes jugadores recreativos

Purpose: The aim of this study was to estimate the effect of unstructured table tennis participation on motor coordination level in young recreational players. Method: A retrospective quasi-experimental study, with ex post facto design, was conducted. Sample was extracted from a population of 207 students aged 12 to 15 years enrolled in a public full-time school. Experimental (n=18) and control (n=18) groups were formed, resulting in a final sample of 36 participants (17 girls, 19 boys). Table tennis participation was experienced inside the school of the participants and consisted of an unstructured activity in which the subjects played recreationally during 30-40 minutes, 3 to 5 times per week, during one year. Post-intervention measures were performed within one week after one-year of table tennis participation. Motor coordination level was assessed using the Körperkoordinationstest für Kinder. Repeated measures analysis of variance was used to examine between- and within-subjects differences. Results: Both groups showed higher values of motor coordination level over one-year. Tennis table participation group had significantly higher motor coordination levels than control group across both time periods (F=12.483, p=0.01). However, the interaction effect between tennis table participation and time was not significant (F=1.552, p=0.221). Conclusion: Motor coordination levels of young recreational players were not improved due to unstructured table tennis participation, even after one year of regular practice. The lack of adequate opportunities for practice may have led to these findings. Additional research involving both structured and unstructured practice of this sport should be pursued

Objetivo: El objetivo de este estudio fue estimar el efecto de la participación no estructurada del tenis de mesa en el nivel de coordinación motora en jóvenes jugadores recreativos. Método: Se realizó un estudio retrospectivo cuasi-experimental. Se extrajo una muestra de una población de 207 estudiantes de 12 a 15 años matriculados en una escuela pública a tiempo completo. Se formaron un grupo experimental (n=18) y control (n=18), resultando una muestra final de 36 participantes (17 chicas y 19 chicos). La participación en tenis de mesa se llevó a cabo dentro de la escuela de los participantes y consistió en una actividad no estructurada en la que los sujetos jugaban recreativamente durante 30-40 minutos, 3 a 5 veces por semana, durante un año. Las medidas post-intervención se realizaron una semana después de completar un año de participación en el tenis de mesa. El nivel de coordinación motora se evaluó utilizando el Körperkoordinationstest für Kinder. El análisis de la varianza de medidas repetidas se utilizó para examinar las diferencias entre los sujetos. Resultados: Ambos grupos mostraron mayores valores de coordinación motora a lo largo de un año. El grupo de participación en tenis de mesa tuvo niveles de coordinación motora significativamente más altos que el grupo control en ambos períodos de tiempo (F=12.483, p=0,01). Sin embargo, el efecto de interacción entre la participación en tenis de mesa y el tiempo no fue significativo (F=1.552, p=0,221). Conclusión: Los niveles de coordinación motora de los jugadores jóvenes recreativos no mejoraron debido a la participación no estructurada en el tenis de mesa, incluso después de un año de práctica regular. La falta de oportunidades adecuadas para la práctica puede haber llevado a estos hallazgos. Debería llevarse a cabo una investigación adicional que incluya tanto la práctica estructurada como la no estructurada de este deporte

Alkaloids in Erythrina by UPLC-ESI-MS and In Vivo Hypotensive Potential of Extractive Preparations.

Erythrina species are used in popular medicine as sedative, anxiolytic, anti-inflammatory, and antihypertensive. In this work, we investigated the chemical composition of extracts obtained from leaves of E. falcata and E. crista-galli. The hypotensive potential of E. falcata and the mechanism of action were also studied. The extracts were obtained by maceration and infusion. The total content of phenolic compounds and flavonoids was estimated by spectrophotometric methods. The chemical constituents were studied performing a chromatographic analysis by UPLC-ESI-MS. For in vivo protocols, blood pressure and heart rate were measured by the invasive hemodynamic monitoring method. Different concentrations of extracts and drugs such as L-NAME, losartan, hexamethonium, and propranolol were administrated i.v. The results of total phenolic contents for E. falcata and E. crista-galli were 1.3193-1.4989 mgGAE/mL for maceration and 0.8771-0.9506 mgGAE/mL for infusion. In total flavonoids, the content was 7.7829-8.1976 mg RE/g for maceration and 9.3471-10.4765 RE mg/g for infusion. The chemical composition was based on alkaloids, suggesting the presence of erythristemine, 11ß-methoxyglucoerysodine, erysothiopine, 11ß-hydroxyerysodine-glucose, and 11-hydroxyerysotinone-rhamnoside. A potent dose-dependent hypotensive effect was observed for E. falcata, which may be related to the route of ß-adrenergic receptors.

Influence of hip external rotation on hip adductor and rectus femoris myoelectric activity during a dynamic parallel squat.

This study sought to compare the myoelectric activity of the hip adductors (HAs) and rectus femoris (RF) when the hip was in a neutral position or externally rotated by 30° or 50° (H0, H30, and H50, respectively) during a parallel squat. Ten healthy subjects performed 10 repetitions of squats in each of the 3 hip positions and the myoelectric activities of the HAs and RF were recorded. The signal was then divided into categories representing concentric (C) and eccentric (E) contractions in the following ranges of motion: 0-30° (C1 and E1), 30-60° (C2 and E2), and 60-90° (C3 and E3) of knee flexion. From those signals, an root mean square (RMS) value for each range of motion in each hip position was obtained. All values were normalized to those obtained during maximum voluntary isometric contraction. We found that HAs showed a significant increase in myoelectric activity during C3 and E3 in the H30 and H50 positions, as compared with H0. Meanwhile, RF activity did not significantly differ between hip positions. Both muscles showed higher activation during 60-90° (C3 and E3) of knee flexion, as compared with 0-30° (C1 and E1) and 30-60° (C2 and E2). The results suggest that if the aim is to increase HA activity despite the low percentage of muscle activation, squats should be performed with 30° of external rotation and at least 90° of knee flexion.

gamma-Zein secondary structure in solution by circular dichroism.

The proline-rich N-terminal domain of gamma-zein has been reported in relevant processes, which include its ability to cross the cell membranes. Evidences indicate that synthetic hexapeptide (PPPVHL), naturally found in N-terminal portion of gamma-zein, can adopt the polyproline II (PPII) conformation in aqueous solution. The secondary structure of gamma-zein in maize protein bodies had been analyzed by solid state Fourier transform infrared and nuclear magnetic resonance spectroscopies. However, it was not possible to measure PPII content in physiological environment since the beta-sheet and PPII signals overlap in both solid state techniques. Here, the secondary structure of gamma-zein has been analyzed by circular dichroism in SDS aqueous solution with and without ditiothreitol (DTT), and in 60% of 2-propanol and water with DTT. The results show that gamma-zein has high helical content in all solutions. The PPII conformation was present at about 7% only in water/DTT solution.

Study of the conformation of gamma-zeins in purified maize protein bodies by FTIR and NMR spectroscopy.

The gamma-zeins are a mixture of 16, 27, and 50-kDa polypeptides which are important in the formation and stabilization of protein bodies (PB). These organelles are used for deposition of zeins, the water-insoluble storage proteins in maize. The nature of the physical interaction between proteins in the assembly and stabilization of PB are fairly well known. It is suggested the repeated hexapeptide sequence (PPPVHL)(8) in the N-terminus is responsible for aggregation of the gamma-zeins on the PB surface. Despite this importance, there is little information about the native conformation of gamma-zeins. In this work, we have analyzed the secondary structures of gamma-zeins in purified protein bodies from two maize cultivars, in the solid state, by FTIR and NMR spectroscopy. The results revealed that gamma-zeins in their physiological state are comprise similar proportions of alpha-helix and beta-sheet, 33 and 31% as determined by FTIR. It was not possible to state if the polyproline II (PPII) conformation is present in the solid-state structure of gamma-zeins, as has been demonstrated for the hexapeptide in solution. Because of the similarity of the solid-state NMR spectra of gamma and alpha-zeins in the alpha carbon region we attributed their contributions to the beta-sheet structures rather than to the PPII conformation or a mixture of these extended structures.