4,735 research outputs found
The polarized expression of Na+,K+-ATPase in epithelia depends on the association between beta-subunits located in neighboring cells
The polarized distribution of Na+,K+-ATPase plays a paramount physiological role, because either directly or through coupling with co- and countertransporters, it is responsible for the net movement of, for example, glucose, amino acids, Ca2+, K+, Cl-, and CO3H- across the whole epithelium. We report here that the beta-subunit is a key factor in the polarized distribution of this enzyme. 1) Madin-Darby canine kidney (MDCK) cells (epithelial from dog kidney) express the Na+,K+-ATPase over the lateral side, but not on the basal and apical domains, as if the contact with a neighboring cell were crucial for the specific membrane location of this enzyme. 2) MDCK cells cocultured with other epithelial types (derived from human, cat, dog, pig, monkey, rabbit, mouse, hamster, and rat) express the enzyme in all (100%) homotypic MDCK/MDCK borders but rarely in heterotypic ones. 3) Although MDCK cells never express Na+,K+-ATPase at contacts with Chinese hamster ovary (CHO) cells, they do when CHO cells are transfected with beta(1)-subunit from the dog kidney (CHO-beta). 4) This may be attributed to the adhesive property of the beta(1)-subunit, because an aggregation assay using CHO (mock-transfected) and CHO-beta cells shows that the expression of dog beta(1)-subunit in the plasma membrane does increase adhesiveness. 5) This adhesiveness does not involve adherens or tight junctions. 6) Transfection of beta(1)-subunit forces CHO-beta cells to coexpress endogenous a-subunit. Together, our results indicate that MDCK cells express Na+,K+-ATPase at a given border provided the contacting cell expresses the dog P,-subunit. The cell-cell interaction thus established would suffice to account for the polarized expression and positioning of Na+,K+-ATPase in epithelial cells
ANÁLISIS DE LAS HABILIDADES MOTRICES BÁSICAS CON MAYOR INFLUENCIA EN LA COORDINACIÓN DINÁMICA GENERAL -ANALYSIS OF BASIC MOTOR SKILLS MORE INFLUENCE ON THE GENERAL DYNAMIC COORDINATION
En este artículo se presenta un análisis de las habilidades motrices básicas que influyen en mayor medida con la coordinación dinámica general. El mismo hace parte de una investigación denominada incidencia de un programa de juegos menores en la coordinación dinámica general de los estudiantes de primer grado en la Institución Educativa Distrital José Antonio Galán de la ciudad de Bogotá, la cual es de carácter cuantitativa apoyada en datos cualitativos, se utilizó un diseño cuasi-experimental y se aplicó la prueba número dos del perfil psicomotor de Picq y Vayer; la población estuvo conformada por los estudiantes de primer grado de la jornada tarde y la muestra la constituyeron 84 niños, donde 43 de ellos hicieron parte del grupo control y 41 del grupo experimental.Se realizó una intervención durante dos meses, tres días por semana, con una batería de 38 juegos menores, los cuales ejercitaban las habilidades motrices básicas con mayor influencia en la coordinación dinámica general.Palabras claves: Aprendizaje motriz, Motricidad, Intervención, Habilidades Motrices. AbstractThis article presents an analysis of basic motor skills higher influencing the coordination dynamics. The same is part of an investigation called incidence of a game program minors in general dynamic coordination of first grade students in the District Educational Institution José Antonio Galán of Bogotá, which is qualitative in character supported by quantitative data, we used a quasi-experimental and applied the test number two Picq and psychomotor profile Vayer, the population consisted of first grade students of the day and evening sample comprised 84 children, where 43 of them were part of the control group and 41 in the experimental group.Intervention was conducted for two months, three days a week, with a battery of 38 minor’s games, which motor skills exercised more influence on the general dynamic coordination.Keywords: Motor learning, motricity, Intervention, Motor Skills.
ULTÍMATE FRISBEE UN ESPÍRITU DEPORTIVO COMO CALIDAD DE VIDA/ULTIMATE FRISBEE A SPORTSMANSHIP QUALITY OF LIFE AS
Los avances tecnológicos nos han afectado en gran manera a las personas sedentarias que en nuestra población se presenta en alto porcentaje, por lo que se ve afectada la salud física, mental y la forma en que nos relacionamos con los demás. Es debido a esto que presento el ultímate frisbee como un deporte y actividad física que puede mejorar la calidad de vida en una amplia población desde chicos a grandes sin restricción alguna, al contrario contribuye en la mejora de su cuerpo, mente y un fortalecimiento social hacia una sana convivencia.Palabras claves: ultímate frisbee, actividad física, deporte, bienestar Psicológico.ASBTRACT Technological advances have greatly affected sedentary people in our population has a high percentage, so health is affected physically, mentally and how we relate to others. It is because of this that I present the Ultimate Frisbee as a sport and physical activity can improve quality of life in a broad populati from children to large without restriction, in contrast helps to improve your body, mind and social empowerment to a healthy coexistence.Key words: Ultimate Frisbee, physical activity, sport, psychological well-being
PERCEPCIÓN DEL ESFUERZO EN ENTRENAMIENTO DE FUTBOLISTAS CATEGORÍA SUB 15 - PERCEPTION OF EFFORT IN TRAINING OF ATHLETES CATEGORY SUB 15
RESUMEN Desde hace un tiempo las ciencias aplicadas al deporte han fijado sus intereses en investigar patrones físicos y mentales en los deportistas, lo que ha permitido tener un mejoramiento a nivel competitivo, al mejorar resultados en los entrenamientos y en las competiciones debido a la pronta intervención de los aspectos negativos en los procesos de entrenamiento, en este caso el futbol tolimense. Para la recolección de datos se utilizó la observación y la verificación de resultados con la real percepción del entrenador, además en el proceso se midieron 13 deportistas de la categoría sub 15 de futbol durante un periodo de 15 sesiones de entrenamiento; para realizar el estudio de la percepción del esfuerzo en entrenamiento se observaron y valoraron en la población objeto del proyecto los siguientes indicadores: condición física, utilizando el test de Ruffier para la aptitud física y el índice de fatiga, con la escala de esfuerzo percibido de Borg; para determinar una posible carga de entrenamiento adecuada según cada uno de sus integrantes, obteniendo como resultado que las cargas desarrolladas por los deportistas del seleccionado tolimense coinciden en su gran mayoría con las cargas percibidas por el entrenador en su planificación deportiva.Palabras clave: condición física, índice de fatiga, percepción del esfuerzo y procesos de entrenamiento. ABSTRACTFor a time sciences applied to the sport they have been fixing its interests to investigating physical and mental patterns in the sportsmen, which has allowed to have an improvement at competitive level, when improving results in the training and the competitions due to the quick intervention of the negative aspects in the training processes, in this case in the football. For the accomplishment of the study, the methodology of data collection that I am used was the observation, the interview and the verification of results with the real perception of the trainer, in the present work were moderate 13 sportsmen of the category sub 15 of football with great interventions in championships at national level, during a period of 15 sessions of training; in order to make the study of the perception of the effort in training they were observed and they valued in the population object of the project the following indicators: physical training conditions, using the test of Ruffier for the medical fitness and the index of fatigue, with the scale of effort perceived of Borg; in order to determine a possible load of training adapted according to each one of its members.Key words: physical training conditions, index of fatigue, perception of the effort and processes of training
Numerical computation of electric field and potential along silicone rubber insulators under contaminated and dry band conditions
Anomalous packing in thin nanoparticle supercrystals
We report a structural study of gold nanoparticle supercrystals formed by a few layers and of micrometer size, where the long-range order has been stimulated by a soft thermal annealing. We have clearly identified an expansion of the first layer lying on amorphous carbon substrate and an ordered second layer sitting on twofold saddle points. The third nanoparticle layer recovers the conventional close-packed stacking. This anomalous packing has been explained by means of a simple theoretical model based on dispersional forces.82265277528
Histological changes and impairment of liver mitochondrial bioenergetics after long-term treatment with alpha-naphthyl-isothiocyanate (ANIT)
This study was designed to evaluate the effects of long-term treatment with alpha-naphthyl-isothiocyanate (ANIT) on liver histology and at the mitochondrial bioenergetic level. Since, ANIT has been used as a cholestatic agent and it has been pointed out that an impairment of mitochondrial function is a cause of hepatocyte dysfunction leading to cholestatic liver injury, serum markers of liver injury were measured and liver sections were analyzed in ANIT-treated rats (i.p. 80 mg/kg/week x 16 weeks). Mitochondrial parameters such as transmembrane potential, respiration, calcium capacity, alterations in permeability transition susceptibility and ATPase activity were monitored. Histologically, the most important features were the marked ductular proliferation, proliferation of mast cells and the presence of iron deposits in ANIT-treated liver. Mitochondria isolated from ANIT-treated rats showed no alterations in state 4 respiration, respiratory control ratio and ADP/O ratio, while state 3 respiration was significantly decreased. No changes were observed on transmembrane potential, but the repolarization rate was decreased in treated rats. Consistently with these data, there was a significant decrease in the ATPase activity of treated mitochondria. Associated with these parameters, mitochondria from treated animals exhibited increased susceptibility to mitochondrial permeability transition pore opening (lower calcium capacity). Since, human cholestatic liver disease progress slowly overtime, these data provide further insight into the role of mitochondrial dysfunction in the process
Percentile reference values for anthropometric body composition indices in European children from the IDEFICS study
INTRODUCTION: To characterise the nutritional status in children with obesity or wasting conditions, European anthropometric reference values for body composition measures beyond the body mass index (BMI) are needed. Differentiated assessment of body composition in children has long been hampered by the lack of appropriate references.
OBJECTIVES: The aim of our study is to provide percentiles for body composition indices in normal weight European children, based on the IDEFICS cohort (Identification and prevention of Dietary-and lifestyle-induced health Effects in Children and infantS).
METHODS: Overall 18 745 2.0-10.9-year-old children from eight countries participated in the study. Children classified as overweight/obese or underweight according to IOTF (N = 5915) were excluded from the analysis. Anthropometric measurements (BMI (N = 12 830); triceps, subscapular, fat mass and fat mass index (N = 11 845-11 901); biceps, suprailiac skinfolds, sum of skinfolds calculated from skinfold thicknesses (N = 8129-8205), neck circumference (N = 12 241); waist circumference and waist-to-height ratio (N = 12 381)) were analysed stratified by sex and smoothed 1st, 3rd, 10th, 25th, 50th, 75th, 90th, 97th and 99th percentile curves were calculated using GAMLSS.
RESULTS: Percentile values of the most important anthropometric measures related to the degree of adiposity are depicted for European girls and boys. Age-and sex-specific differences were investigated for all measures. As an example, the 50th and 99th percentile values of waist circumference ranged from 50.7-59.2 cm and from 51.3-58.7 cm in 4.5-to < 5.0-year-old girls and boys, respectively, to 60.6-74.5 cm in girls and to 59.9-76.7 cm in boys at the age of 10.5-10.9 years.
CONCLUSION: The presented percentile curves may aid a differentiated assessment of total and abdominal adiposity in European children
Predicting the onset and persistence of episodes of depression in primary health care. The predictD-Spain study: Methodology
Background:
The effects of putative risk factors on the onset and/or persistence of depression remain unclear. We aim to develop comprehensive models to predict the onset and persistence of episodes of depression in primary care. Here we explain the general methodology of the predictD-Spain study and evaluate the reliability of the questionnaires used.
Methods:
This is a prospective cohort study. A systematic random sample of general practice attendees aged 18 to 75 has been recruited in seven Spanish provinces. Depression is being measured with the CIDI at baseline, and at 6, 12, 24 and 36 months. A set of individual, environmental, genetic, professional and organizational risk factors are to be assessed at each follow-up point. In a separate reliability study, a proportional random sample of 401 participants completed the test-retest (251 researcher-administered and 150 self-administered) between October 2005 and February 2006. We have also checked 118,398 items for data entry from a random sample of 480 patients stratified by province.
Results:
All items and questionnaires had good test-retest reliability for both methods of administration, except for the use of recreational drugs over the previous six months. Cronbach's alphas were good and their factorial analyses coherent for the three scales evaluated (social support from family and friends, dissatisfaction with paid work, and dissatisfaction with unpaid work). There were 191 (0.16%) data entry errors.
Conclusion:
The items and questionnaires were reliable and data quality control was excellent. When we eventually obtain our risk index for the onset and persistence of depression, we will be able to determine the individual risk of each patient evaluated in primary health car
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