112 research outputs found

    Análisis del comportamiento táctico ofensivo en momentos críticos de juego en el alto rendimiento en balonmano: Un estudio Mixed Methods

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    El objetivo del artículo es analizar las variables que influyen enlas fases ofensivas críticas del balonmano de alto rendimiento desde unaperspectiva dinámica ecológica y con un planteamiento Mixed Methods.Evaluamos los diferentes sistemas tácticos ofensivos en ataque posicionaly en contraataque de las últimas diez posesiones del balón y acciones ofensivasde partidos de balonmano de élite mediante un análisis observacionalen dos etapas. Una primera etapa CUALI, materializada en forma de registrodescriptivo, que permitieron la construcción de un sistema de observación(SOCTO); y una segunda etapa CUANTI con la que obtuvimosun registro sistematizado posterior mediante las siguientes dimensiones: elmarcador, el tipo de defensa, la simetría numérica, la zona de finalizacióny el tipo de finalización. Utilizando el software de registro LINCE, se observaron19 partidos de las fases finales masculinas del Campeonato delMundo 2011, Campeonato de Europa 2012 y Juegos Olímpicos 2012. Elanálisis descriptivo inicial realizada por entrenadores expertos se ha complementadocon un análisis de T-patterns. Los resultados reafirman que enlos momentos críticos y de desigualdad del final de los partidos los equiposperdedores utilizan en la fase ofensiva las zonas de finalización más alejadasde la portería contraria (zona de 9 metros) y los equipos ganadores utilizanen la fase ofensiva las zonas de finalización intermedias (entre 6 y 9 metros)aumentando así su eficacia

    Statin‐induced myopathy: Translational studies from preclinical to clinical evidence

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    Statins are the most prescribed and effective drugs to treat cardiovascular diseases (CVD). Nevertheless, these drugs can be responsible for skeletal muscle toxicity which leads to reduced compliance. The discontinuation of therapy increases the incidence of CVD. Thus, it is essential to assess the risk. In fact, many studies have been performed at preclinical and clinical level to investigate pathophysiological mechanisms and clinical implications of statin myotoxicity. Consequently, new toxicological aspects and new biomarkers have arisen. Indeed, these drugs may affect gene transcription and ion transport and contribute to muscle function impairment. Identifying a marker of toxicity is important to prevent or to cure statin induced myopathy while assuring the right therapy for hypercholesterolemia and counteracting CVD. In this review we focused on the mechanisms of muscle damage discovered in preclinical and clinical studies and high-lighted the pathological situations in which statin therapy should be avoided. In this context, preventive or substitutive therapies should also be evaluated

    La percepción de beneficios y de mejora del equilibrio motriz en programas de actividad física en la tercera edad

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    Nuestro objetivo es estudiar la percepción de los beneficios yde la mejora del equilibrio motriz que tienen los participantes de la terceraedad en un programa de actividad física. Realizamos un enfoque mixedmethods de tipo embedded design de los datos obtenidos de la observaciónsistematizada de los patrones motrices que generan programas dirigidos aeste colectivo; la administración de un test estandarizado de equilibrio engeriatría y un cuestionario validado. Se analizaron 19 sesiones de actividadfísica para obtener los patrones motrices que se desarrollan en dichos programas.Aplicamos el sistema de observación OSMOS_in context, codificadomediante LINCE v.1 y la subsiguiente detección de T-Patterns medianteTHEME v.6, La puntuación del equilibrio motriz, administrando la escalade Tinetti, se obtuvo de los 90 participantes de los programas. Los datosde la percepción de beneficios se han obtenido a partir del cuestionariorealizando un análisis de contenido, mediante el software Atlas-ti v. 6.2.Los T-patterns que hemos obtenido muestran el trabajo específico de estabilidadmotriz de manera conjunta a otras capacidades y habilidades motricesespecíficas, aspectos que se corroboran en la puntuación de la escala deTinetti y que los participantes corroboran y relacionan con una mejoría enla percepción de beneficios tanto físicos como sociales

    Timing of adjuvant chemotherapy after limb amputation and effect on outcome in dogs with appendicular osteosarcoma without distant metastases

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    Objective: To determine an optimal time interval between amputation and initiation of adjuvant chemotherapy (TIamp-chemo) in dogs with appendicular osteosarcoma without distant metastases and whether TIamp-chemo was associated with outcome. Animals: 168 client-owned dogs treated at 9 veterinary oncology centers. Procedures: Data were collected from the dogs' medical records concerning potential prognostic variables and outcomes. Dogs were grouped as to whether they received chemotherapy within 3, 5, 7, 10, 15, 20, 30, or > 30 days after amputation of the affected limb. Analyses were performed to identify variables associated with time to tumor progression and survival time after limb amputation and to determine an optimal TIamp-chemo. Results: Median TIamp-chemo was 14 days (range, 1 to 210 days). Median time to tumor progression for dogs with a TIamp-chemo ≤ 5 days (375 days; 95% CI, 162 to 588 days) was significantly longer than that for dogs with a TIamp-chemo > 5 days (202 days; 95% CI, 146 to 257 days). Median overall survival time for dogs with a TIamp-chemo ≤ 5 days (445 days; 95% CI, 345 to 545 days) was significantly longer than that for dogs with a TIamp-chemo > 5 days (239 days; 95% CI, 186 to 291 days). Conclusions and clinical relevance: Findings indicated that early (within 5 days) initiation of adjuvant chemotherapy after limb amputation was associated with a significant and clinically relevant survival benefit for dogs with appendicular osteosarcoma without distant metastases. These results suggested that the timing of chemotherapy may be an important prognostic variabl

    A revised genome assembly of the region 5' to canine SOX9 includes the revsex orthologous region

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    The SOX gene family includes many genes that play a determinant role in several developmental pathways. The SOX9 gene has been identified as a major factor in testis development in mammals after it is activated by the SRY gene. However, duplication of the gene itself in some mammalian species, or of a well-delimited upstream 'RevSex' region in humans, has been shown to result in testis development in the absence of the SRY gene. In the current study, we present an accurate analysis of the genomic organization of the SOX9 locus in dogs by both in silico and FISH approaches. Contrary to what is observed in the current dog genome assembly, we found that the genomic organization is quite similar to that reported in humans and other mammalian species, including the position of the RevSex region in respect to SOX9. The analysis of the conserved sequences within this region in 7 mammalian species facilitated the highlighting of a consensus sequence for SRY binding. This new information could help in the identification of evolutionarily conserved elements relevant for SOX9 gene regulation, and could provide valid targets for mutation analysis in XY DSD patients

    Gain-of-Function STIM1 L96V Mutation Causes Myogenesis Alteration in Muscle Cells From a Patient Affected by Tubular Aggregate Myopathy

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    Tubular Aggregate Myopathy (TAM) is a hereditary ultra-rare muscle disorder characterized by muscle weakness and cramps or myasthenic features. Biopsies from TAM patients show the presence of tubular aggregates originated from sarcoplasmic reticulum due to altered Ca2+ homeostasis. TAM is caused by gain-of-function mutations in STIM1 or ORAI1, proteins responsible for Store-Operated-Calcium-Entry (SOCE), a pivotal mechanism in Ca2+ signaling. So far there is no cure for TAM and the mechanisms through which STIM1 or ORAI1 gene mutation lead to muscle dysfunction remain to be clarified. It has been established that post-natal myogenesis critically relies on Ca2+ influx through SOCE. To explore how Ca2+ homeostasis dysregulation associated with TAM impacts on muscle differentiation cascade, we here performed a functional characterization of myoblasts and myotubes deriving from patients carrying STIM1 L96V mutation by using fura-2 cytofluorimetry, high content imaging and real-time PCR. We demonstrated a higher resting Ca2+ concentration and an increased SOCE in STIM1 mutant compared with control, together with a compensatory down-regulation of genes involved in Ca2+ handling (RyR1, Atp2a1, Trpc1). Differentiating STIM1 L96V myoblasts persisted in a mononuclear state and the fewer multinucleated myotubes had distinct morphology and geometry of mitochondrial network compared to controls, indicating a defect in the late differentiation phase. The alteration in myogenic pathway was confirmed by gene expression analysis regarding early (Myf5, Mef2D) and late (DMD, Tnnt3) differentiation markers together with mitochondrial markers (IDH3A, OGDH). We provided evidences of mechanisms responsible for a defective myogenesis associated to TAM mutant and validated a reliable cellular model usefull for TAM preclinical studies

    Ergogenic effect of bcaas and l-alanine supplementation: Proof-of-concept study in a murine model of physiological exercise

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    Background: Branched-chain amino acids (BCAAs: leucine, isoleucine, valine) account for 35% of skeletal muscle essential amino acids (AAs). As such, they must be provided in the diet to support peptide synthesis and inhibit protein breakdown. Although substantial evidence has been collected about the potential usefulness of BCAAs in supporting muscle function and structure, dietary supplements containing BCAAs alone may not be effective in controlling muscle protein turnover, due to the rate-limiting bioavailability of other AAs involved in BCAAs metabolism. Methods: We aimed to evaluate the in vivo/ex vivo effects of a 4-week treatment with an oral formulation containing BCAAs alone (2:1:1) on muscle function, structure, and metabolism in a murine model of physiological exercise, which was compared to three modified formulations combining BCAAs with increasing concentrations of L-Alanine (ALA), an AA controlling BCAAs catabolism. Results: A preliminary pharmacokinetic study confirmed the ability of ALA to boost up BCAAs bioavailability. After 4 weeks, mix 2 (BCAAs + 2ALA) had the best protective effect on mice force and fatigability, as well as on muscle morphology and metabolic indices. Conclusion: Our study corroborates the use of BCAAs + ALA to support muscle health during physiological exercise, underlining how the relative BCAAs/ALA ratio is important to control BCAAs distribution

    Sox9 Duplications Are a Relevant Cause of Sry-Negative XX Sex Reversal Dogs

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    Sexual development in mammals is based on a complicated and delicate network of genes and hormones that have to collaborate in a precise manner. The dark side of this pathway is represented by pathological conditions, wherein sexual development does not occur properly either in the XX and the XY background. Among them a conundrum is represented by the XX individuals with at least a partial testis differentiation even in absence of SRY. This particular condition is present in various mammals including the dog. Seven dogs characterized by XX karyotype, absence of SRY gene, and testicular tissue development were analysed by Array-CGH. In two cases the array-CGH analysis detected an interstitial heterozygous duplication of chromosome 9. The duplication contained the SOX9 coding region. In this work we provide for the first time a causative mutation for the XXSR condition in the dog. Moreover this report supports the idea that the dog represents a good animal model for the study of XXSR condition caused by abnormalities in the SOX9 locus

    ClC-1 mutations in myotonia congenita patients: insights into molecular gating mechanisms and genotype-phenotype correlation

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    Loss-of-function mutations of the skeletal muscle ClC-1 channel cause myotonia congenita with variable phenotypes. Using patch clamp we show that F484L, located in the conducting pore, probably induces mild dominant myotonia by right-shifting the slow gating of ClC-1 channel, without exerting a dominant-negative effect on the wild-type (WT) subunit. Molecular dynamics simulations suggest that F484L affects the slow gate by increasing the frequency and the stability of H-bond formation between E232 in helix F and Y578 in helix R. Three other myotonic ClC-1 mutations are shown to produce distinct effects on channel function: L198P shifts the slow gate to positive potentials, V640G reduces channel activity, while L628P displays a WT-like behaviour (electrophysiology data only). Our results provide novel insight into the molecular mechanisms underlying normal and altered ClC-1 function
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