Topographical cues of PLGA membranes modulate the behavior of hMSCs, myoblasts and neuronal cells.

Biomaterial surface modification through the introduction of defined and repeated patterns of topography helps study cell behavior in response to defined geometrical cues. The lithographic molding technique is widely used for conferring biomaterial surface microscale cues and enhancing the performance of biomedical devices. In this work, different master molds made by UV mask lithography were used to prepare poly (D,L-lactide-co-glycolide) - PLGA micropatterned membranes to present different features of topography at the cellular interface: channels, circular pillars, rectangular pillars, and pits. The effects of geometrical cues were investigated on different cell sources, such as neuronal cells, myoblasts, and stem cells. Morphological evaluation revealed a peculiar cell arrangement in response to a specific topographical stimulus sensed over the membrane surface. Cells seeded on linear-grooved membranes showed that this cue promoted elongated cell morphology. Rectangular and circular pillars act instead as discontinuous cues at the cell-membrane interface, inducing cell growth in multiple directions. The array of pits over the surface also highlighted the precise spatiotemporal organization of the cell; they grew between the interconnected membrane space within the pits, avoiding the microscale hole. The overall approach allowed the evaluation of the responses of different cell types adhered to various surface patterns, build-up on the same polymeric membrane, and disclosing the effect of specific topographical features. We explored how various microtopographic signals play distinct roles in different cells, thus affecting cell adhesion, migration, differentiation, cell-cell interactions, and other metabolic activities.

The Effectiveness of the Psychological Intervention in Amateur Male Marathon Runners.

Background: The Marathon runners must have the proper technical preparation to reach excellence and to achieve adequate psychological preparation for the race. Against this background, the current study aims to describe the implementation results of a cognitive-behavioral intervention based on psychological skills training for marathon runners. Methods: Fourteen amateur male marathoners with an average age of 30 (SD = 5.75) were trained with various emotional and cognitive control techniques to enhance their performance in competition. Various psychological variables, related to the subjects level of perceived stress, and to qualitative characteristics of their thoughts were measured before and after the target marathon race. Results were analyzed through non-parametric tests for two related samples. The Cohen's d effect size for single-group pretest-posttest repeated measures were also performed. Results: Statistical analysis reveals that, controlling for age and running experience, the intervention decreased significantly the level of perceived stress and the occurrence of negative thoughts before the race, during, and after the race. Conclusion: Training in cognitive control and relaxation techniques, as part of the psychological skills training could determine the quality of performance of marathon runners.

Male and female grassroots football players: Yellow, red cards and incidents. What's the difference?

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