96 research outputs found
Análisis del perfil fisiológico, metabólico y estructural del tenis de mesa desde una perspectiva de género
En las últimas dos décadas el tenis de mesa ha experimentado importantes transformaciones en su reglamento y en los materiales de juego. Estas modificaciones han supuesto una evolución hacia un tenis de mesa más moderno y dinámico. Diversas investigaciones describen el esfuerzo y la dinámica de juego del tenis de mesa masculino. Sin embargo, existe un gran desconocimiento de la estructura de juego y del impacto que supone la práctica de este deporte en las mujeres. El objetivo de este estudio ha sido analizar la respuesta fisiológica y metabólica y la estructura de juego del tenis de mesa actual considerando a ambos géneros. Una muestra de 48 jugadores de elite (24 jugadores y 24 jugadoras), participaron en una competición simulada para evaluar la respuesta cardiaca, los niveles de lactato y diferentes parámetros estructurales de juego. Se han encontrado diferencias entre el juego masculino y femenino en los registros cardíacos mínimos (p<0,004) y máximos (p<0,001), en los niveles de lactato (p<0,001), en los tiempos de juego (p<0,01) y en el número de golpeos efectuado por jugada (p<0,01). El tenis de mesa se caracteriza en ambos géneros por la realización de esfuerzos submáximos, una gran variabilidad cardiaca y un metabolismo de predominio anaeróbico aláctico. El juego desarrollado en la competición masculina es más rápido y explosivo que el de la femenina caracterizado por efectuarse un mayor número de golpeos por jugada. Se hace necesario la realización de nuevos estudios en donde se considere el estilo de juego y los materiales de juego utilizado por los deportistas analizados. Esta investigación resulta de gran interés y relevancia en la actualidad por ser pionera en el tenis de mesa femenino describiendo el esfuerzo y la dinámica de juego que lo caracteriza
Comunidad de roedores en el municipio de san marcos, sucre, colombia
The aim of this research was to determinate the composition of rodent communities in urban and rural areas from San Marcos, Sucre, Colombia. Rodents were sampled using Sherman traps from December 2007 to July 2009, with a capture effort of 1200 night traps (capture success 12%). A total of 144 rodents were captured, eight species were registered: Mus musculus (60), Zygodontomys brevicauda (44), Rattus rattus (21), Oryzomys azuerensis (10), Oligoryzomys fulvescens (4), Neacomys spinosus (2), Proechiymys cayennensis (2), and Heteromys anomalus (1). The number of murinae rodents was higher in urban habitats, whereas wild rodent species of subfamily Sigmodontinae were dominant in rural areas. In addition, the highest percentage of population consisted of adult males. Data suggest that characteristics of habitats (homogeneity and heterogeneity) were important factors on species distribution and diversity of rodents in both urban and rural area.El objetivo de esta investigación fue determinar la composición de las comunidades de roedores en áreas urbanas y rurales del municipio de San Marcos, Sucre, Colombia. Los roedores fueron muestreados empleando trampas tipo Sherman desde diciembre de 2007 hasta julio de 2009, con un esfuerzo de captura de 1200 trampas-noche (éxito de captura 12%). Fueron capturados un total de 144 individuos, registrándose 8 especies: Mus musculus (60), Zygodontomys brevicauda (44), Rattus rattus (21), Oryzomys azuerensis (10), Oligoryzomys fulvescens (4), Neacomys spinosus (2), Proechiymys cayennensis (2) y Heteromys anomalus (1). El número de roedores murinos fue mayor en hábitats urbanos, mientras en ambientes rurales predominaron las especies silvestres de la subfamilia Sigmodontinae. Además, el mayor porcentaje de la población correspondió a machos adultos. Los resultados sugieren que las condiciones (homogeneidad y heterogeneidad) de los hábitats fueron determinantes en la distribución y diversidad de los roedores tanto en ambientes urbanos como rurales
Cortical Visual Evoked Potentials and Growth in Infants Fed with Bioactive Compounds-Enriched Infant Formula: Results from COGNIS Randomized Clinical Trial
Postnatal nutrition is essential for growth and neurodevelopment. We analyzed the
influence of a new enriched-infant formula with bioactive compounds on growth, neurodevelopment,
and visual function (VF) in healthy infants during their first 18 months of life. A total of 170 infants
were randomized in the COGNIS randomized clinical trial (RCT) to receive a standard infant formula
(SF = 85) or a new experimental infant formula supplemented with functional nutrients (EF = 85). As a
control, 50 breastfed infants (BF) were enrolled. Growth patterns were evaluated up to 18 months of
life; neurodevelopment was assessed by general movements at 2, 3, and 4 months; VF was measured by
cortical visual evoked potentials at 3 and 12 months. No differences in growth and neurodevelopment
were found between groups. Regarding VF, SF and EF infants presented prolonged latencies and
lower amplitudes in the P100 wave than BF infants. In the EF group, a higher percentage of infants
presented response at 7 1/2' of arc at 12 months compared to 3 months of age; a similar proportion of BF
and EF infants presented responses at 7 1/2' of arc at 12 months of age. Early nutritional intervention
with bioactive compounds could narrow the gap in growth and neurodevelopment between breastfed
and formula-fed infants.This project has been funded by Ordesa Laboratories, S.L. Contract University of Granada General
Foundation, No. 3349 and SMARTFOODS (CIEN) Contract University of Granada General Foundation, No.
4003, Spanish Ministry of Economy, Industry and Competitiveness; funded in part by HORIZON 2020 EU
DynaHEALTH Project (GA No.633595)
Infant Formula Supplemented With Milk Fat Globule Membrane, Long-Chain Polyunsaturated Fatty Acids, and Synbiotics Is Associated With Neurocognitive Function and Brain Structure of Healthy Children Aged 6 Years: The COGNIS Study
Background: Adequate nutrient intake during the first few months of life plays a critical role on brain structure and function development. Objectives: To analyze the long-term effects of an experimental infant formula (EF) on neurocognitive function and brain structure in healthy children aged 6 years compared to those fed with a standard infant formula or breastfed. Methods: The current study involved 108 healthy children aged 6 years and participating in the COGNIS Study. At 0-2 months, infants were randomized to receive up to 18 months of life a standard infant formula (SF) or EF enriched with milk fat globule membrane (MFGM), long-chain polyunsaturated fatty acids (LC-PUFAs) and synbiotics. Furthermore, a reference group of breastfed (BF) infants were also recruited. Children were assessed using neurocognitive tests and structural Magnetic Resonance Imaging (MRI) at 6 years old. Results: Experimental infant formula (EF) children showed greater volumes in the left orbital cortex, higher vocabulary scores and IQ, and better performance in an attention task than BF children. EF children also presented greater volumes in parietal regions than SF kids. Additionally, greater cortical thickness in the insular, parietal, and temporal areas were found in children from the EF group than those fed with SF or BF groups. Further correlation analyses suggest that higher volumes and cortical thickness of different parietal and frontal regions are associated with better cognitive development in terms of language (verbal comprehension) and executive function (working memory). Finally, arachidonic acid (ARA), adrenic acid (AdA), docosahexaenoic acid (DHA) levels in cheek cell glycerophospholipids, ARA/DHA ratio, and protein, fatty acid, and mineral intake during the first 18 months of life seem to be associated with changes in the brain structures at 6 years old. Conclusions: Supplemented infant formula with MFGM components, LC-PUFAs, and synbiotics seems to be associated to long-term effects on neurocognitive development and brain structure in children at 6 years old.This project has been funded by Laboratorios Ordesa, S.L. Contract University of Granada General Foundation, No. 3349 and SMARTFOODS (CIEN) Contract University of Granada General Foundation, No. 4003, Spanish Ministry of Economy, Industry and Competitiveness. Furthermore, the project has been partially funded by HORIZON 2020 EU DynaHEALTH Project (GA No. 633595).S
The Mre11-Rad50-Nbs1 complex mediates activation of TopBP1 by ATM
The activation of ATR-ATRIP in response to double-stranded DNA breaks (DSBs) depends upon ATM in human cells and Xenopus egg extracts. One important aspect of this dependency involves regulation of TopBP1 by ATM. In Xenopus egg extracts, ATM associates with TopBP1 and thereupon phosphorylates it on S1131. This phosphorylation enhances the capacity of TopBP1 to activate the ATR-ATRIP complex. We show that TopBP1 also interacts with the Mre11-Rad50-Nbs1 (MRN) complex in egg extracts in a checkpoint-regulated manner. This interaction involves the Nbs1 subunit of the complex. ATM can no longer interact with TopBP1 in Nbs1-depleted egg extracts, which suggests that the MRN complex helps to bridge ATM and TopBP1 together. The association between TopBP1 and Nbs1 involves the first pair of BRCT repeats in TopBP1. In addition, the two tandem BRCT repeats of Nbs1 are required for this binding. Functional studies with mutated forms of TopBP1 and Nbs1 suggested that the BRCT-dependent association of these proteins is critical for a normal checkpoint response to DSBs. These findings suggest that the MRN complex is a crucial mediator in the process whereby ATM promotes the TopBP1-dependent activation of ATR-ATRIP in response to DSBs
Rad17 Plays a Central Role in Establishment of the Interaction between TopBP1 and the Rad9-Hus1-Rad1 Complex at Stalled Replication Forks
Rad17 is critical for the ATR-dependent activation of Chk1 during checkpoint responses. It is known that Rad17 loads the Rad9-Hus1-Rad1 (9-1-1) complex onto DNA. We show that Rad17 also mediates the interaction of 9-1-1 with the ATR-activating protein TopBP1 in Xenopus egg extracts. Studies with Rad17 mutants indicate that binding of ATP to Rad17 is essential for the association of 9-1-1 and TopBP1. Furthermore, hydrolysis of ATP by Rad17 is necessary for the loading of 9-1-1 onto DNA and the elevated, checkpoint-dependent accumulation of TopBP1 on chromatin. Significantly, a mutant 9-1-1 complex that cannot bind TopBP1 has a normal capacity to promote elevated accumulation of TopBP1 on chromatin. Taken together, we propose the following mechanism. First, Rad17 loads 9-1-1 onto DNA. Second, TopBP1 accumulates on chromatin in a manner that depends on both Rad17 and 9-1-1. Finally, 9-1-1 and TopBP1 dock in a Rad17-dependent manner before activation of Chk1
Context specificity of post-error and post-conflict cognitive control adjustments
There has been accumulating evidence that cognitive control can be adaptively regulated by monitoring for processing conflict as an index of online control demands. However, it is not yet known whether top-down control mechanisms respond to processing conflict in a manner specific to the operative task context or confer a more generalized benefit. While previous studies have examined the taskset-specificity of conflict adaptation effects, yielding inconsistent results, controlrelated performance adjustments following errors have been largely overlooked. This gap in the literature underscores recent debate as to whether post-error performance represents a strategic, control-mediated mechanism or a nonstrategic consequence of attentional orienting. In the present study, evidence of generalized control following both high conflict correct trials and errors was explored in a task-switching paradigm. Conflict adaptation effects were not found to generalize across tasksets, despite a shared response set. In contrast, post-error slowing effects were found to extend to the inactive taskset and were predictive of enhanced post-error accuracy. In addition, post-error performance adjustments were found to persist for several trials and across multiple task switches, a finding inconsistent with attentional orienting accounts of post-error slowing. These findings indicate that error-related control adjustments confer a generalized performance benefit and suggest dissociable mechanisms of post-conflict and post-error control. © 2014 Forster, Cho
Localization of the Drosophila Rad9 Protein to the Nuclear Membrane Is Regulated by the C-Terminal Region and Is Affected in the Meiotic Checkpoint
Rad9, Rad1, and Hus1 (9-1-1) are part of the DNA integrity checkpoint control system. It was shown previously that the C-terminal end of the human Rad9 protein, which contains a nuclear localization sequence (NLS) nearby, is critical for the nuclear transport of Rad1 and Hus1. In this study, we show that in Drosophila, Hus1 is found in the cytoplasm, Rad1 is found throughout the entire cell and that Rad9 (DmRad9) is a nuclear protein. More specifically, DmRad9 exists in two alternatively spliced forms, DmRad9A and DmRad9B, where DmRad9B is localized at the cell nucleus, and DmRad9A is found on the nuclear membrane both in Drosophila tissues and also when expressed in mammalian cells. Whereas both alternatively spliced forms of DmRad9 contain a common NLS near the C terminus, the 32 C-terminal residues of DmRad9A, specific to this alternative splice form, are required for targeting the protein to the nuclear membrane. We further show that activation of a meiotic checkpoint by a DNA repair gene defect but not defects in the anchoring of meiotic chromosomes to the oocyte nuclear envelope upon ectopic expression of non-phosphorylatable Barrier to Autointegration Factor (BAF) dramatically affects DmRad9A localization. Thus, by studying the localization pattern of DmRad9, our study reveals that the DmRad9A C-terminal region targets the protein to the nuclear membrane, where it might play a role in response to the activation of the meiotic checkpoint
Performance breakdown effects dissociate from error detection effects in typing
Mistakes in skilled performance are often observed to be slower than correct actions. This error slowing has been associated with cognitive control processes involved in performance monitoring and error detection. A limited literature on skilled actions, however, suggests that preerror actions may also be slower than accurate actions. This contrasts with findings from unskilled, discrete trial tasks, where preerror performance is usually faster than accurate performance. We tested 3 predictions about error-related behavioural changes in continuous typing performance. We asked participants to type 100 sentences without visual feedback. We found that (a) performance before errors was no different in speed than that before correct key-presses, (b) error and posterror key-presses were slower than matched correct key-presses, and (c) errors were preceded by greater variability in speed than were matched correct key-presses. Our results suggest that errors are preceded by a behavioural signature, which may indicate breakdown of fluid cognition, and that the effects of error detection on performance (error and posterror slowing) can be dissociated from breakdown effects (preerror increase in variability). © 2013 © 2013 The Experimental Psychology Society
Multiple Regulatory Mechanisms to Inhibit Untimely Initiation of DNA Replication Are Important for Stable Genome Maintenance
Genomic instability is a hallmark of human cancer cells. To prevent genomic instability, chromosomal DNA is faithfully duplicated in every cell division cycle, and eukaryotic cells have complex regulatory mechanisms to achieve this goal. Here, we show that untimely activation of replication origins during the G1 phase is genotoxic and induces genomic instability in the budding yeast Saccharomyces cerevisiae. Our data indicate that cells preserve a low level of the initiation factor Sld2 to prevent untimely initiation during the normal cell cycle in addition to controlling the phosphorylation of Sld2 and Sld3 by cyclin-dependent kinase. Although untimely activation of origin is inhibited on multiple levels, we show that deregulation of a single pathway can cause genomic instability, such as gross chromosome rearrangements (GCRs). Furthermore, simultaneous deregulation of multiple pathways causes an even more severe phenotype. These findings highlight the importance of having multiple inhibitory mechanisms to prevent the untimely initiation of chromosome replication to preserve stable genome maintenance over generations in eukaryotes
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