Mentales Training - Für und Wider bei ästhetisch-kompositorischen Sportarten

Mentales Training hat sich im Sport als Ergänzung zu herkömmlichen Methoden für das Erlernen und Stabilisieren von Bewegungsfertigkeiten etabliert. Da es sich vorwiegend bei kognitiven Aufgaben günstig auf die Leistung auswirkt, ist davon auszugehen, dass sportliche Disziplinen mit hohem technischen Anforderungsniveau besonders davon profitieren. Dies würde für die ästhetisch-kompositorischen Sportarten Kunstturnen und Eiskunstlauf zutreffen. Da jedoch der Großteil der motorischen Fertigkeiten in beiden Sportarten zwischen dem sechsten Lebensjahr und der Pubertät erlernt wird, stellt sich die Frage nach der Anwendbarkeit Mentalen Trainings im Kindes- und Jugendalter.Mental training has developed to become a complement to traditional methods for learning and stabilising movement skills in sports. Having positive effects on performance principally on cognitive tasks, it is expected that mental training will be particularly beneficial in sports disciplines with high technical requirements. This would apply to the aesthetic-compositional disciplines of artistic gymnastics and figure skating. However, most of the movement skills in both disciplines are acquired between the 6th year of age and puberty, which gives rise to the question for the applicability of mental training during infancy and adolescence. Subsequently on a presentation on the subject matter of the used terms (mental training, visualization, imagery, mental imagery, mental rehearsal …), especially theories explaining the effectiveness of mental training are addressed in detail, presenting some basic concepts of the most various aspects of mental training. This summary of the current state of research is followed by a descriptive individual case study of a 15 years old figure skater (mental training of the double Axel) and a 7 years old artistic gymnast (mental training of the forward bow). This study examines the applicability of mental training for learning movements through the five-steps Eberspächer concept. The aim is to ensure the applicability of mental training during infancy with focussed propaedeutic visualization, an increased practical imagery as well as a more intensive co-operation between the coach and the athlete during all coaching sessions. The presentation shows, which problems occurred during coaching, how they were reacted to and which differences appear in dealing with this training method as compared to adolescent athletes. The study is based on the assumption that a different approach towards mental training results from the latter rather than from cognitive gestation, due to the short coaching period. The pros and cons of mental training during infancy are highlighted by means of practical coaching and the implementation of the findings in scripts of movements already mastered and are compared with the results of adolescent athletes in order to see if a suitable approach to mental training can be found for children. In spite of improved movements by both athletes, significant variations appear between the athletes during infancy and adolescence, showing that mental training can only be used to a very limited extent for learning movements during infancy

Depletion of Dendritic Cells Enhances Innate Anti-Bacterial Host Defense through Modulation of Phagocyte Homeostasis

Dendritic cells (DCs) as professional antigen-presenting cells play an important role in the initiation and modulation of the adaptive immune response. However, their role in the innate immune response against bacterial infections is not completely defined. Here we have analyzed the role of DCs and their impact on the innate anti-bacterial host defense in an experimental infection model of Yersinia enterocolitica (Ye). We used CD11c-diphtheria toxin (DT) mice to deplete DCs prior to severe infection with Ye. DC depletion significantly increased animal survival after Ye infection. The bacterial load in the spleen of DC-depleted mice was significantly lower than that of control mice throughout the infection. DC depletion was accompanied by an increase in the serum levels of CXCL1, G-CSF, IL-1α, and CCL2 and an increase in the numbers of splenic phagocytes. Functionally, splenocytes from DC-depleted mice exhibited an increased bacterial killing capacity compared to splenocytes from control mice. Cellular studies further showed that this was due to an increased production of reactive oxygen species (ROS) by neutrophils. Adoptive transfer of neutrophils from DC-depleted mice into control mice prior to Ye infection reduced the bacterial load to the level of Ye-infected DC-depleted mice, suggesting that the increased number of phagocytes with additional ROS production account for the decreased bacterial load. Furthermore, after incubation with serum from DC-depleted mice splenocytes from control mice increased their bacterial killing capacity, most likely due to enhanced ROS production by neutrophils, indicating that serum factors from DC-depleted mice account for this effect. In summary, we could show that DC depletion triggers phagocyte accumulation in the spleen and enhances their anti-bacterial killing capacity upon bacterial infection

Guidelines for the use of flow cytometry and cell sorting in immunological studies

International audienceThe classical model of hematopoiesis established in the mouse postulates that lymphoid cells originate from a founder population of common lymphoid progenitors. Here, using a modeling approach in humanized mice, we showed that human lymphoid development stemmed from distinct populations of CD127(-) and CD127(+) early lymphoid progenitors (ELPs). Combining molecular analyses with in vitro and in vivo functional assays, we demonstrated that CD127(-) and CD127(+) ELPs emerged independently from lympho-mono-dendritic progenitors, responded differently to Notch1 signals, underwent divergent modes of lineage restriction, and displayed both common and specific differentiation potentials. Whereas CD127(-) ELPs comprised precursors of T cells, marginal zone B cells, and natural killer (NK) and innate lymphoid cells (ILCs), CD127(+) ELPs supported production of all NK cell, ILC, and B cell populations but lacked T potential. On the basis of these results, we propose a "two-family" model of human lymphoid development that differs from the prevailing model of hematopoiesis