Análisis cinemático del viraje en el esquí alpino de competición

Esta comunicación trata sobre la aplicación de la Biomecánica Deportiva como perspectiva científica, al análisis cinemático del esquí alpino como objeto de estudio, y ha sido realizada basándose en una situación real de competición como fue el Campeonato del Mundo de 1996 celebrado en Sierra Nevada (Granada). Para el análisis de la muestra, utilizamos la metodología y las tecnologías propias de la biomecánica Deportiva como son el método indirecto y las técnicas fotogramétricas tridimensionales, basadas en la filmación del gesto deportivo utilizando el vídeo. Los resultados obtenidos muestran la existencia de un patrón general de movimiento en la muestra de esquiadoras analizadas en cuanto a las velocidades tangenciales medias del CG(S).del sistema (esquiador más implementos). Entre las conclusiones, destacamos la existencia de una reducción de la velocidad tangencial media resultante en el recorrido analizado que es mayor aún, en el instante de paso del palo de viraje en particular y cuanto más curva es la trayectoria. Atendiendo a la desviación típica del comportamiento de la velocidad media resultante, podemos decir que en este tramo de paso de la puerta encontramos las diferencias entre la técnica individual de las esquiadoras analizadas. Este estudio nos confirma la importancia del entrenamiento en situación real de competición (en cuanto a material, características pista de entrenamiento, etc.

Efficacy of DOPE/DC-cholesterol liposomes and GCPQ micelles as AZD6244 nanocarriers in a 3D colorectal cancer in vitro model

Aim: In this work, we use cationic organic nanocarriers as chemotherapy delivery platforms and test them in a colorectal cancer 3D in vitro model. Materials & methods: We used 3beta-(N-[N′,N′-dimethylaminoethane]carbamoyl])cholesterol (DC-chol) and dioleoylphosphatidylethanolamine (DOPE) liposomes and N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) micelles, to deliver AZD6244, a MEK inhibitor, to HCT116 cells cultured as monolayers and in 3D in vitro cancer models (tumoroids). Results: Nanoparticle-mediated drug delivery was superior to the free drug in monolayer experiments and despite their therapeutic effect being hindered by poor diffusion through the cancer mass, GCPQ micelles were also superior in tumoroids. Conclusion: These results support the role of nanoparticles in improving drug delivery and highlight the need to include 3D cancer models in early phases of drug development

Efficacy of DOPE/DC-cholesterol liposomes and GCPQ micelles as AZD6244 nanocarriers in a 3D colorectal cancer in vitro model

AIM: In this work, we use cationic organic nanocarriers as chemotherapy delivery platforms and test them in a colorectal cancer 3D in vitro model. MATERIALS & METHODS: We used 3beta-(N-[N',N'-dimethylaminoethane]carbamoyl])cholesterol (DC-chol) and dioleoylphosphatidylethanolamine (DOPE) liposomes and N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) micelles, to deliver AZD6244, a MEK inhibitor, to HCT116 cells cultured as monolayers and in 3D in vitro cancer models (tumoroids). RESULTS: Nanoparticle-mediated drug delivery was superior to the free drug in monolayer experiments and despite their therapeutic effect being hindered by poor diffusion through the cancer mass, GCPQ micelles were also superior in tumoroids. CONCLUSION: These results support the role of nanoparticles in improving drug delivery and highlight the need to include 3D cancer models in early phases of drug development

Fully relativistic calculation of magnetic properties of Fe, Co and Ni adclusters on Ag(100)

We present first principles calculations of the magnetic moments and magnetic anisotropy energies of small Fe, Co and Ni clusters on top of a Ag(100) surface as well as the exchange-coupling energy between two single adatoms of Fe or Co on Ag(100). The calculations are performed fully relativistically using the embedding technique within the Korringa-Kohn-Rostoker method. The magnetic anisotropy and the exchange-coupling energies are calculated by means of the force theorem. In the case of adatoms and dimers of iron and cobalt we obtain enhanced spin moments and, especially, unusually large orbital moments, while for nickel our calculations predict a complete absence of magnetism. For larger clusters, the magnitudes of the local moments of the atoms in the center of the cluster are very close to those calculated for the corresponding monolayers. Similar to the orbital moments, the contributions of the individual atoms to the magnetic anisotropy energy strongly depend on the position, hence, on the local environment of a particular atom within a given cluster. We find strong ferromagnetic coupling between two neighboring Fe or Co atoms and a rapid, oscillatory decay of the exchange-coupling energy with increasing distance between these two adatoms.Comment: 8 pages, ReVTeX + 4 figures (Encapsulated Postscript), submitted to PR

The efficacy of cetuximab in a tissue-engineered three-dimensional in vitro model of colorectal cancer.

The preclinical development process of chemotherapeutic drugs is often carried out in two-dimensional monolayer cultures. However, a considerable amount of evidence demonstrates that two-dimensional cell culture does not accurately reflect the three-dimensional in vivo tumour microenvironment, specifically with regard to gene expression profiles, oxygen and nutrient gradients and pharmacokinetics. With this objective in mind, we have developed and established a physiologically relevant three-dimensional in vitro model of colorectal cancer based on the removal of interstitial fluid from collagen type I hydrogels. We employed the RAFT™ (Real Architecture For 3D Tissue) system for producing three-dimensional cultures to create a controlled reproducible, multiwell testing platform. Using the HT29 and HCT116 cell lines to model epidermal growth factor receptor expressing colorectal cancers, we characterized three-dimensional cell growth and morphology in addition to the anti-proliferative effects of the anti-epidermal growth factor receptor chemotherapeutic agent cetuximab in comparison to two-dimensional monolayer cultures. Cells proliferated well for 14 days in three-dimensional culture and formed well-defined cellular aggregates within the concentrated collagen matrix. Epidermal growth factor receptor expression levels revealed a twofold and threefold increase in three-dimensional cultures for both HT29 and HCT116 cells in comparison to two-dimensional monolayers, respectively (p < 0.05; p < 0.01). Cetuximab efficacy was significantly lower in HT29 three-dimensional cultures in comparison to two-dimensional monolayers, whereas HCT116 cells in both two-dimension and three-dimension were non-responsive to treatment in agreement with their KRAS mutant status. In summary, these results confirm the use of a three-dimensional in vitro cancer model as a suitable drug-screening platform for in vitro pharmacological testing

Comparison of fiber effect on glycemic index and glycemic load in differents types of bread

Indexación: Scopus; Redalyc.Existen diversos alimentos que contienen como nutriente principal hidratos de carbono, destacando entre ellos el pan por su masivo consumo a nivel mundial. Numerosos estudios se han llevado a cabo con el fin de reducir su índice glicémico, sin embargo, aún existe controversia sobre la acción de la fibra dietética en la disminución del IG en este alimento. Este estudio determinó el efecto de la fibra dietética sobre el índice glicémico y carga glicémica en dos tipos de panes comerciales en 23 individuos sanos quienes consumieron aleatoriamente 3 diferentes productos, de 50 g de carbohidratos cada uno, durante 6 días: pan blanco (PH), pan integral (PF), y solución glucosada como producto de referencia (SG). Se midió glicemia en ayunas y post-prandial a los tiempos 15, 30, 45, 60, 90 y 120 min. La insulina fue medida en el minuto 0 y 120 min. El área bajo la curva de glicemia resultó más baja para ambos tipos de pan PH 13589 ±1557, PF 12005 ±1254 que para el producto de referencia SG 14089 ±1245. Los valores del índice glicémico PH 68,55 ±1,2 y PF 62,10 ±1,3 y carga glicémica PH 16,45 ±1,4 resultaron más bajos para el pan con mayor aporte de fibra 9,93 ± 1,1, sin diferencias en la concentración de insulina, sugiriendo que la cantidad de carbohidratos y tipo de fibra contenidos en el pan integral, pueden considerarse factores intrínsecos en su composición nutricional, capaces de afectar la respuesta glicémica post- ingesta de estos productos en individuos sanos.There are several foods that contain carbohydrates as the main nutrient, being one of the most important the bread for its massive worldwide consumption. Numerous studies have been done in order to reduce its glycemic index, however there is still controversy about the action of dietary fiber in the decrease of GI in this product. In this study, it was determined the effect of dietetic fiber on glycemic index and glycemic load in two types of commercial breads in 23 healthy individuals who randomly consumed 3 different products during 6 days of 50g of carbohydrates each: white bread (PH), whole wheat bread (PE) and glucose solution as reference product (SG). Fasting and postprandial glycemia was measured at times 15, 30, 45, 60, 90 and 120 minutes. Insuline was measured at 0 min and 120 min. The area under de glycemia curve was lower for both bread types PH 13589 ±1557, PF 12005 ±1254 than for the reference product SG 14089 ±1245. The values of the glycemic index PH 68,55 ±1,2 and PF 62,01 ±1,3 and glycemic load PH 16.45 ±1,4 were lower for bread with more amount fiber 9,93 ± 1,1, with no difference in insulin concentration, suggesting that the amount of carbohydrates and fiber type contained in whole wheat bread can be considered intrinsic factors in bread composition, affecting the post-intake glycemic response of this type of products in healthy individuals.http://www.redalyc.org/articulo.oa?id=5594990800

Genomic prediction models for grain yield of spring bread wheat in diverse agro-ecological zones

Genomic and pedigree predictions for grain yield and agronomic traits were carried out using high density molecular data on a set of 803 spring wheat lines that were evaluated in 5 sites characterized by several environmental co-variables. Seven statistical models were tested using two random cross-validations schemes. Two other prediction problems were studied, namely predicting the lines’ performance at one site with another (pairwise-site) and at untested sites (leave-one-site-out). Grain yield ranged from 3.7 to 9.0 t ha−1 across sites. The best predictability was observed when genotypic and pedigree data were included in the models and their interaction with sites and the environmental co-variables. The leave-one-site-out increased average prediction accuracy over pairwise-site for all the traits, specifically from 0.27 to 0.36 for grain yield. Days to anthesis, maturity, and plant height predictions had high heritability and gave the highest accuracy for prediction models. Genomic and pedigree models coupled with environmental co-variables gave high prediction accuracy due to high genetic correlation between sites. This study provides an example of model prediction considering climate data along-with genomic and pedigree information. Such comprehensive models can be used to achieve rapid enhancement of wheat yield enhancement in current and future climate change scenario

Effect of oat β-glucan on glycemic index and glycemic load of a nutritional supplement sweetened with sucralose in healthy adults: A randomized clinical trial

Indexación: Scopus; RedalycLas propiedades hipoglicemiantes del β-glucano de avena son de interés para la industria alimentaria y el área clínica, por sus potenciales beneficios sobre la salud al disminuir la respuesta glicémica, el nivel sérico de lipoproteínas de baja densidad y el índice glicémico de los alimentos. Existen suplementos nutricionales específicos para diabéticos edulcorados con sucralosa cuyo índice glicémico y carga glicémica aún no han sido establecidos. El efecto del β-glucano de avena sobre el índice glicémico y carga glicémica de un suplemento nutricional edulcorado con sucralosa, fue determinado en 13 adultos sanos (6 hombres y 7 mujeres), quienes consumieron aleatoriamente 4 alimentos en días distintos, de 50 g de carbohidratos cada uno: suplemento nutricional para diabéticos (FN), suplemento nutricional con β-glucano (FN- β), y como productos de referencia: solución glucosada (SG) y pan blanco (PB). Se midió glicemia en ayunas y post- prandial a los tiempos 15, 30, 45, 60, 90 y 120 min. El área bajo la curva de glicemia resultó más baja para ambas fórmulas (FN) 12697±993, (FN-β) 11584 ±1171, que para los productos de referencia:(SG) 13900±1245, y (PB) 13267 ± 1557. Los valores de índice glicémico (FN) 67,02 ± 5,69, así como la carga glicémica resultaron intermedios y más bajos para el suplemento con β-glucano incorporado (FN –β) 59,8 ± 6,2; sin diferencias en la concentración de insulina, sugiriendo que la adición del β-glucano derivado de la avena reduce la velocidad de absorción intestinal de la glucosa, efecto que podría estudiarse en diabéticos.The hypoglycemic properties of oat β-glucan is of interest for the food industry and clinical area, for potencial health benefits by reducing glycemic response, serum low-density lipoprotein cholesterol, and glycemic index of meals. There are specific nutritional supplements for diabetics sweetened with sucralose whose glycemic index and glycemic load has not been established. Effect of oat β-glucan on glycemic index and glycemic load of a nutritional supplement sweetened with sucralose in healthy adults was determined in 13 healthy subjects (6 men and 7 women) old that consumed randomly 4 meals of 50 g of carbohydrates each in different days: a nutritional supplement for diabetics (FN), the nutritional supplement with β-glucan incorporated (FN-β) and two reference food, glucose solution (SG) and white bread (PB). Fasting and postprandial glycemia was measured at times 15, 30, 45, 60, 90 and 120 min. The area under the glycemia curve was lower for both formulas (FN) 12697±993, (FN-β) 11584 ±1171 than for reference products (SG) 13900±1245, y (PB) 13267 ± 1557. The values of glycemic index (GI) (FN) 67, 02 ± 5,69 and glycemic load were intermediate and more lower for the supplement with β-glucan incorporated (FN –β) 59, 8 ± 6,2, with no difference of insulin concentration . Suggesting that the addition of oat-derived β-glucan reduces the rate of intestinal absorption of glucose. This effect should be studied in diabetic.http://www.redalyc.org/articulo.oa?id=5594990800

Comment on "Evidence from acoustic imaging for submarine volcanic activity in 2012 off the west coast of El Hierro (Canary Islands, Spain)" by Pérez NM, Somoza L, Hernández PA, González de Vallejo L, León R, Sagiya T, Biain A, González FJ, Medialdea T, Barrancos J, Ibáñez J, Sumino H, Nogami K and Romero C [Bull Volcanol (2014) 76:882-896]

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Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors