Troubles anorectaux chez les patients ayant une sclérose en plaques : physiopathologie, prévalence, impact et prise en charge

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Submental sensitive transcutaneous electrical stimulation reverses virtual lesion of the oropharyngeal cortex

ObjectiveThe aim of this study was to assess the effect of submental sensitive transcutaneous electrical stimulation (SSTES) on pharyngeal cortical representation after a virtual pharyngeal lesion in healthy subjects.MethodsMotor-evoked potentials of the mylohyoid muscles and videofluoroscopic parameters were measured before and after the creation of the virtual lesion, at the end of SSTES (T0), at 30minutes (T30) and 60minutes (T60).ResultsNine subjects completed the study. After 20minutes of SSTES, there was an increase of motor-evoked potential amplitude at 0 and 30min (P<0.05). There was no significant modification of videofluoroscopic measurements. Regarding the cortical mapping after SSTES, there was an increase in the number of points with a cortical response in the dominant hemisphere but also in the non-dominant hemisphere, effect which remained constant at 60minutes (P<0.05).DiscussionSSTES is effective on cortical plasticity for the mylohyoid muscles and reverses pharyngeal cortical inhibition in healthy subjects. It could therefore be a simple non-invasive way to treat post-stroke dysphagia

Quantifying the gender load: can population crosses reveal interlocus sexual conflict?

Six sister populations of Drosophila melanogaster kept under identical environmental conditions for greater than 600 generations were reciprocally crossed to investigate the incidence of population divergence in allopatry. Population crosses directly influenced fitness, mating frequency, and sperm competition patterns. Changes in both female remating rate and the outcome of male sperm competition (P(1), P(2)) in response to foreign males were consistent with intersexual coevolution. Moreover, seven of the 30 crosses between foreign mates resulted in significant reductions in female fitness, whereas two resulted in significant increases, compared to local matings. This tendency for foreign males to reduce female fitness may be interpreted as evidence for either sexually antagonistic coevolution or the disruption of mutualistic interactions. However, instances in which female fitness improved via cohabitation with foreign males may better reveal sexual conflict, signalling release from the cost of interacting with locally adapted males. By this metric, female reproduction in D. melanogaster is strongly constrained by local adaptation by males, a situation that would promote antagonistic coevolution between the sexes. We conclude that sexual selection can promote population differentiation in allopatry and that sexual conflict is likely to have played a role in population differentiation in this study system