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Intracellular free Ca2+ signals antibiotic exposure in cyanobacteria

  • González-Pleiter, M.
  • Leganés, Francisco
  • Fernández-Piñas, Francisca
Intracellular free Ca2+, [Ca2+]i, is a key element of the cellular response to many abiotic and biotic stresses. Cyanobacteria are ancient organisms which have evolved signal transduction systems in response to an ever changing environment. Cyanobacteria have been found to respond to specific and quick Ca2+ signatures (unique combinations of changes in [Ca2+]i) when exposed to environmental stress. Antibiotics are bioactive molecules which are being considered as pseudopersistent contaminants as they are being continuously released to the environment; although non-target organisms, cyanobacteria as prokaryotes are sensitive to antibiotics. In order to check whether [Ca2+]i could be involved in sensing antibiotic exposure, we have recorded the Ca2+ signatures induced by antibiotics belonging to different classes at two effective toxicity concentrations, the EC10 and the EC50. For that, we have used a recombinant bioluminescent strain of the cyanobacterium Anabaena sp. PCC7120 that constitutively expresses the calcium-binding indicator protein, apoaequorin. We found that Ca2+ signatures upon exposure to antibiotics were induced quickly (2-3 seconds) and that they differed between antibiotics and antibiotic concentration. As different classes of antibiotics have been detected simultaneously in the aquatic environment, we also recorded and analyzed the Ca2+ signatures induced by binary mixtures and a multiantibiotic mixture; we found that these Ca2+ signatures could determine the nature of the interaction between antibiotics in the mixture, whether synergistic or antagonistic, well before toxicity was evident. To our knowledge, this study is the first report of intracellular free Ca2+ as an early biomarker of antibiotic exposure in the environment, This research was supported by CTM2013-45775-C2-2-R and CGL2010-15675 grants from MINECO/FEDER EU. MGP holds an FPI grant from MINECO/FEDER EU

Atom-economical regioselective Ni-catalyzed hydroborylative cyclization of enynes: Development and mechanism

  • Cabrera-Lobera, Natalia
  • Quirós, M. Teresa
  • Buñuel, Elena
  • Cárdenas, Diego J.
We report a full study on the novel regioselective Ni-catalyzed hydroborylative cyclization of enynes using HBpin as the borylation agent. Alkyl and alkenyl boronates can be obtained depending on the substituent on the alkyne. The reaction takes place under smooth conditions with an inexpensive catalytic Ni-based system, constituting a fully atom-economic eco-friendly method. This process shows a broad scope, allowing the formation of carbo- and heterocycles in moderate to good yields. The utility of the resulting boronates is also illustrated. We have studied the reaction mechanism both experimentally and computationally. The process involves initial oxidative cyclometalation to Ni(0)(xantphos) species followed by the key C-B bond formation through σ-bond metathesis and reductive elimination, We thank the Spanish MINECO for funding (Grant CTQ2016-79826-R) and a Juan de la Cierva fellowship to M. T. Q., the MECD for a FPU fellowship to N. C.-L., and the Centro de Computación Científica-UAM

La importancia de la profundidad del contramovimiento en el ciclo estiramiento-acortamiento, Importance of countermovement depth in stretching and shortening cycle analysis

  • Sánchez-Sixto, A.
  • Harrison, A. J.
  • Floría, P.
El objetivo de la presente investigación fue determinar la influencia de las variables relacionadas con la aplicación de fuerza y el desplazamiento del centro de masas en las diferencias en la altura saltada entre el salto sin contramovimiento (SJ) y el salto con contramovimiento (CMJ). Participaron veintiséis hombres, realizando tres SJ y tres CMJ con 90° de flexión de rodilla. El desplazamiento del centro de masas y la fuerza media durante la fase de propulsión fueron significativamente superiores en el CMJ en comparación con el SJ, explicando el 75% de la diferencia entre los dos saltos y teniendo un 30% más de influencia el desplazamiento del centro de masas. No hubo diferencias en la fuerza máxima. Los resultados sugieren la necesidad de examinar el desplazamiento del centro de masas para interpretar adecuadamente las diferencias entre el SJ y el CMJ cuando el criterio establecido es 90° de flexión de rodilla, The aim of this investigation was to determine the influences of force application related variables and center of mass displacement on jump height differences between squat jump (SJ) and countermovement jump (CMJ). Twenty six males performed three squat jumps and three countermovement jumps with a 90° knee flexion. The center of mass displacement during the upward movement phase and the average force were significantly greater in CMJ than in SJ. Both variables explained 75% of the differences in the flight height, having 30% more influence the center of mass displacement. There were no differences in peak force. The results of this research suggest the need to examine the center of mass displacement during SJ and CMJ when a 90°of knee flexion criteria is established

Participación e influencia del líbero en recepción y defensa, en voleibol juvenil, Participation and Influence of the libero in recepcion and defence, in volleyball U-19

  • Sánchez, M.
  • González-Silva, J.
  • Fernández-Echeverría, C.
  • Claver, F.
  • Moreno, M. P.
El objetivo fue conocer la participación e influencia líbero en fase de ataque y defensa, en etapas de formación. La muestra fueron 6948 acciones de juego, realizadas por los jugadores de los 21 equipos del Campeonato de España Juvenil masculino. Las variables fueron: función del receptor/defensor, zona de recepción/defensa en profundidad y lateralidad, eficacia de recepción/defensa, zona donde se realiza colocación en recepción/defensa, zona hacia donde se realiza la colocación en recepción/defensa, tiempo de ataque/contraataque y eficacia de ataque/contraataque. En recepción, existió asociación significativa entre función del receptor y zona de recepción en profundidad-lateralidad, y zona donde se realiza la colocación. En defensa, existió asociación significativa entre función del defensor y zona de defensa en profundidad-lateralidad, eficacia de defensa, zona donde se realiza la colocación, zona hacia donde se realiza la colocación y tiempo de contraataque. La influencia del líbero, en estas etapas, se manifiesta más en defensa que en recepción, The aim was to know the participation and influence of the libero in side-out phase and counter-attack, in young athletes. The sample was 6948 game actions, carried out by the players of the 21 teams that participate in the Under-19 Spanish Championship. The variables were: player that intervened in reception/dig, depth and laterality reception/dig zone, reception/dig efficacy, setting zone in reception/dig, set´s area in reception/dig, tempo of attack/counterattack and attack/counterattack efficacy. In reception, showed significant association between player that intervened in reception, depth-laterality reception zone and the setting zone. In defense, showed significant association between the player that intervened in dig and the depth-laterality dig zone, dig efficacy, setting zone, set´s area and tempo of counterattack. The influence of the participation of the libero, in young athletes, appeared more often in defense than in the reception

Reverse Trojan-horse effect decreased wastewater toxicity in the presence of inorganic nanoparticles

  • Martín-De-Lucía, Idoia
  • Campos-Mañas, Marina C.
  • Agüera, Ana
  • Rodea-Palomares, Ismael
  • Pulido-Reyes, Gerardo
  • Leganés, Francisco
  • Fernández-Piñas, Francisca
  • Rosal, Roberto
We studied the toxicological interaction of 46 micropollutants from a biologically treated wastewater effluent in mixtures with silica, amine-modified silica, titanium dioxide and magnetite nanoparticles. The pollutants tracked in this work were polar pharmaceuticals belonging to different therapeutic groups, some of their metabolites and artificial sweeteners, the concentrations of which were mostly in the tens to hundreds of ng L-1 range. The results showed particularly high adsorption for furosemide, gemfibrozil and the aminopyrine metabolite 4FAA. There was preferential adsorption of the less polar compounds on the less polar nanoparticles. The total amounts of compounds adsorbed and quantified were 13.4, 4.8, 10.8 and 7.1 μg g-1 for SiO2, SiO2-NH2, TiO2 and Fe3O4, respectively. The toxicity of wastewater-nanoparticle mixtures was assessed using the bioluminescent cyanobacterium Anabaena sp. PCC 7120 CPB4337. The interactions were quantified by means of the combination index (CI)-isobologram method. The binary mixtures of wastewater with SiO2, SiO2-NH2 and TiO2 displayed antagonism for the lower affected fractions, which corresponded to the lower concentrations. For higher effects and for the Fe3O4 nanoparticles over the whole tested range, the mixtures were additive leading to synergism for the higher affected fractions. No internalization was observed. The results showed that the reduced toxicant bioavailability due to the interaction with nanoparticles is relevant for micropollutants at environmental concentrations. The amount of anthropogenic pollutants retained by metal oxide nanoparticles has significant toxicological effects, Financial support was provided by FP7-ERA-Net Susfood, 2014/00153/001, the Spanish Ministry of Economy, CTM2013-45775-C2-1-R and CTM2013-45775-C2-2-R and the Dirección General de Universidades e Investigación de la Comunidad de Madrid, Network S2013/MAE-2716

Diferencias motoras en atletas cadetes de taekwondo según nivel competitivo, Motor differences in cadet taekwondo athletes according to competition level

  • De la Fuente, A.
  • Gómez-Landero Rodríguez, L. A.
El objetivo de este estudio es observar las diferencias entre atletas cadetes de Taekwondo de diferentes niveles competitivos en términos antropométricos, de potencia muscular, flexibilidad y velocidad de reacción. Veinte atletas varones fueron analizados, divididos en dos grupos: medallistas nacionales y no medallistas nacionales. Para cada atleta se tomaron datos antropométricos, de velocidad de reacción, potencia muscular y rango de movimiento articular de la articulación coxofemoral. Los atletas medallistas mostraron valores significativamente menores en altura, envergadura, tiempo de reacción óculo-podal, y tiempo de reacción óculo-manual con mano no dominante; y valores mayores para longitud de piernas, flexión pasiva de cadera, y abducción de cadera tanto activa como pasiva. Las leves diferencias observadas entre grupos en potencia muscular, grasa corporal y flexión activa de cadera no concuerdan con estudios previos. Conocer está información podría ser de interés para los entrenadores para llevar a cabo programas de detección de talentos, The aim of this study was to determine the differences between Taekwondo cadet athletes belonging to different competition levels in terms of anthropometry, legs power, flexibility and reaction time. Twenty male athletes were analysed, divided in two groups: national medallist and non-national medallist. Data of every athlete’s anthropometric measurements, reaction speed ability, leg power and hip ROM (range of movement) were taken. Medallist athletes showed significantly lower values for height, arm span, foot reaction time (dominant and non-dominant) and non-dominant hand reaction time; and higher values for leg length, passive hip flexion, active hip abduction and passive hip abduction in ROM tests. Slight differences observed between medallists and non-medallists in leg power (CMJ), body fat (Σ skinfolds) and active hip flexion do not agree with previous studies. Knowing this information could be interesting for coaches in order to carry out talent detection programs

José Enrique Rodríguez Cal: Primer medallista español de boxeo olímpico, First spanish medalist of olympic boxing

  • Calle Molina, María Teresa
  • Martínez Gorroño, María Eugenia
Este artículo parte del trabajo de investigación sobre la reconstrucción histórica de la trayectoria deportiva de José Enrique Rodríguez Cal, primer medallista de boxeo español. La metodología se desarrolló a partir del análisis documental de fuentes primarias, entrevistas y grupos de discusión con el proceso posterior de contraste y triangulación. El resultado supone la recuperación de las circunstancias históricas del equipo nacional de boxeo de aquel periodo y un rescate único, original e inédito de un fragmento de la “historia de vida” deportiva de Rodríguez Cal, cubriendo una de las múltiples lagunas de la Historia del Deporte español. Las condiciones precarias en aquel periodo en cuanto a los materiales, instalaciones y entrenamientos, así como la procedencia de entornos socio-económicos desfavorecidos eran aspectos comunes entre los boxeadores en aquel momento, suponiendo un precedente único el logro de una medalla olímpica en esta disciplina deportiva, This article is part of the research on the historical reconstruction of the sporting career of José Enrique Rodríguez Cal, the first Spanish boxing medalist. The methodology was developed from the documentary analysis of primary sources, interviews and discussion groups with the subsequent process of contrast and triangulation. The result is the recovery of the historical circumstances of the national boxing team of that period and a unique, original and unprecedented rescue of a fragment of "life history" of Rodríguez Cal, covering one of the many shortcomings of the History of the Spanish sports. The precarious conditions in that period in terms of materials, facilities and training, as well as the origin of disadvantaged socio-economic environments were common aspects among boxers at that time, being a unique precedent the achievement of an Olympic medal in this sport discipline

Efecto de un periodo competitivo sobre el perfil antropométrico de árbitros de fútbol, Effects of a competitive period on the anthropometric profile of soccer referees

  • Castillo, D.
  • Cámara, J.
  • Yanci, J.
El objetivo de este estudio fue analizar el efecto de un periodo competitivo de 10 semanas sobre las características antropométricas, la composición corporal y el somatotipo de árbitros de fútbol. 14 árbitros de fútbol (28,8 ± 5,1 años) de distintas categorías nacionales de fútbol de España participaron en este estudio. Se observó un descenso significativo tras este periodo competitivo en el sumatorio de ocho pliegues (Δ = -6,07%, p < 0,05, d = 0,38, bajo). Además, se observó un descenso significativo en el porcentaje de masa adiposa (Δ= -2,29%, p < 0,05, d = 0,19, trivial) y en el componente endomorfo (Δ= -6,82%, p < 0,05, d = 0,32, bajo) en el postest. Un periodo competitivo de 10 semanas parece ser suficiente como para provocar modificaciones en el somatotipo y un descenso del sumatorio de pliegues y de la masa adiposa en árbitros, The aim of this study was to analyze the effect of a 10-week competitive period on body composition, anthropometric characteristics and somatotype in soccer referees. Fourteen officials (28.8 ± 5.1 yr) from different national soccer categories of Spain took part in the study. A decrease in the sum of eight skinfold thicknesses (Δ = -6.07%, p < 0.05, d = 0.38, low) was observed after the competitive period. Moreover, decreases in adipose mass (Δ= -2.29%, p < 0.05, d = 0.19, trivial) and endomorphic component were also observed. A 10-week competitive period has demonstrated to decrease both skinfold thicknesses and adipose mass, changing the somatotype of the referees

Estilo de vida y distribución de grasa en adolescentes asmáticos y sanos, Lifestyle and fat distribution in asthmatic and healthy adolescents

  • García, J. A.
  • Cárdenas, A.
  • Burgos, S.
  • Santiago, C.
  • Hernández, F.
  • Sanz, V.
  • Fernández-del-Valle, M.
  • Rubio, M.
  • Pérez, M.
Introducción: el objetivo es analizar el estilo de vida, en función del ejercicio y la dieta, de un grupo de adolescentes de la Comunidad de Madrid, teniendo en cuenta género y patología y su relación con el estado nutricional, la distribución de grasa y la función pulmonar. Metodología: Estudio descriptivo de 207 sujetos que analizó el estilo de vida a partir del nivel de actividad física (AF) y la adherencia a la dieta mediterránea, el estado nutricional y la distribución de grasa, y la salud respiratoria. Resultados: El grupo de no asmáticos fue más activo (p=0,003) y presentó menor ICT (p=0,001) que el grupo de asmáticos. Se encontraron diferencias significativas dentro del grupo sin asma en nivel de AF siendo los varones más activos (p=0,01) y presentando menor índice cintura-talla (ICT) que las mujeres del mismo grupo (p=0,001). Conclusiones: Los adolescentes no asmáticos fueron más activos y presentaron mejor distribución de grasa que los asmáticos, Objectives: objective is to analyze the lifestyle, integrating exercise and diet, of a group of adolescents from the Community of Madrid, taking into account gender and pathology and its relationship with nutritional status, fat distribution and lung function in adolescents with or without asthma. Methods: This was a descriptive study including 207 subjects aged 13.20 ± 0.62 years. Lifestyle was assessed in terms of physical activity (PA) levels, Mediterranean diet, nutritional status, and respiratory health measured through FEV1 (z). Results: In the non-asthma group, boys were more active (p = 0.01) and showed a lower waist-to-height ratio (WHtR) than girls (p = 0.001). Participants without asthma were more active (p = 0.003), and had a better WHtR (p = 0.001) and FEV1 (p = 0.001) than those with asthma. Conclusions: In this Spanish population sample, non-asthmatic adolescents were more active and showed a better nutritional status, fat distribution and respiratory health than their peers with asthma, Financiado a través de la VII Convocatoria Real Madrid-Universidad Europea (Ref 2015/03RM); Tercer premio en los XV Premios Neumomadrid; Beca Jóvenes Investigadores de la SENP 2015.

Trazas del deporte en los juegos de Brueghel (S.XVI) y Rodrigo Caro (S.XVII), Traces of sport in the games of Brueghel (16th century) and Rodrigo Caro (17th century)

  • Lavega-Burgués, P.
  • Navarro-Adelantado, V.
El objetivo de este trabajo consistió en desvelar en dos contextos europeos en qué medida se incorporan rasgos etnomotores del deporte en los juegos de los siglos XVI y XVII. Se aplican los fundamentos de la praxiología motriz y se realiza un estudio comparado de 117 juegos recogidos en la obra de Brueghel (Bélgica, 1560) y Rodrigo Caro (España, 1626). Se analizan cuatro dimensiones etnomotrices de la lógica interna (13 categorías) y la lógica externa o institucional (8 categorías) del deporte moderno: codificación (presencia o ausencia de reglas); enfrentamiento motor (tipo de interacción motriz); contabilidad (existencia o ausencia de marcador final); materialidad (acondicionamiento del terreno y objetos de juego). Los resultados muestran un patrón de cambio hacia rasgos etnomotores del deporte moderno, con mayor presencia de: exhaustividad de reglas (codificación); duelos simétricos sin agresividad corporal (control del enfrentamiento motor); marcador final (contabilidad); uso de zonas y objetos específicos (materialidad), The aim of this study was to establish the extent to which the ethnomotor features of sport were incorporated into games of the 16th and 17th centuries within two European contexts. Motor praxeology concepts were applied and a comparative study of 117 games contained in the works of Bruegel (Belgium, 1560) and Rodrigo Caro (Spain, 1626) was conducted. Four ethnomotor dimensions of the internal logic (13 categories) and the external or institutional logic (8 categories) of modern sport were analysed: codification (presence or absence of rules); motor confrontation (type of motor interaction); counting (presence or absence of a final score); and materiality (preparation of playing field and equipment). The results show a pattern of change towards the ethnomotor features of modern sport, with a higher presence of: comprehensive rules (codification); symmetrical matches without bodily aggression (control of motor confrontation); final score (counting); and use of specific areas and objects (materiality)

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