Update PONV – Was gibt es Neues bei der Prophylaxe und Therapie von postoperativer Übelkeit und postoperativem Erbrechen?

Die Anaesthesiologie - Auch wenn für Anästhesiologen über Jahrzehnte die Prophylaxe und Therapie postoperativer Schmerzen im Rahmen des postoperativen Patientenkomforts an vorderster...     

Interrelationships between Cellular Density,Mosaic Patterning,and Dendritic Coverage of VGluT3 Amacrine Cells

Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina.     

Factors Influencing Adolescent Girls’ Sexual Behavior: A Secondary Analysis of the 2011 Youth Risk Behavior Survey

Adolescence is a tumultuous and challenging time period in life. Sexual risk behavior among adolescents is a widespread topic of interest in the current literature. Two common factors that influence increased sexual risk behavior are symptoms of depression and negative body image. The purpose of this study was to investigate the effect of body image and symptoms of depression upon sexual risk-taking in an adolescent female population. A secondary data analysis of the 2011 Youth Risk Behavior Survey (YRBS) was used to explore girls’ sexual activity, body image, and mental health. There were 7,708 high-school girls who participated in this study. Three questions were used to represent the constructs under investigation. There were significant correlations between sexual activity, body image, and symptoms of depression; only symptoms of depression were significant predictors of both sexual activity and condom usage. Body image was a predictor of sexual activity, but not condom use. Our findings support previous studies that suggested that people with depressive symptoms were more likely to engage in risky sexual behaviors. Our study also supports the idea that a negative body image decreases sexual activity; however, other researchers have reported that negative body image leads to an increase in sexual activity.