Emotional triggers and psychopathology associated with suicidal ideation in urban children with elevated aggressive-disruptive behavior.

8.6% suicidal ideation (SI) was found among 349 urban 6-9 year olds in the top tercile of aggressive-disruptive behavior. SI was associated with more self-reported depression, ODD, conduct problems, and ADHD symptoms (ES 0.70-0.97) and 3.5-5 times more clinically significant symptoms. Parents rated more symptoms in older children associated with SI compared to parents of similar age children without SI, including greater somatic and behavior problems in 8-9 year olds with SI. Parent ratings did not differentiate SI and non-SI in 6-7 year olds. SI frequently co-occurred with thoughts about death. Children described anger, dysphoria and interpersonal conflict as motivators/triggers for SI and worries about safety/health as motivator/triggers for thoughts about death, suggesting that problems managing emotionally challenging situations are a specific factor in initiating SI. Universal and indicated interventions for children to strengthen emotional self-regulation and behavioral control are recommended to complement the current emphasis on suicide prevention among adolescents.

Scotopic and photopic visual thresholds and spatial and temporal discrimination evaluated by behavior of mice in a water maze.

Methods that allow specific manipulations of the mouse genome have made it possible to alter specific aspects of photoreceptor function within the mouse retina. Mice with photoreceptors that have altered photosensitivities and altered photoresponse kinetics are now available. Methods are needed that can show how those perturbations in photoreceptor response characteristics translate into perturbations in visual sensitivity and perception. We have adapted a previously described method to evaluate visual threshold, spatial discrimination and temporal discrimination in mice swimming in a water maze. In this report we describe the sensitivities of rod-mediated and cone-mediated vision using GNAT1-/-and GNAT2-/- mice. Cone-mediated vision is approximately 10,000 times less sensitive than rod-mediated vision in mice. We also demonstrate that mice can distinguish striped from solid objects in the water maze and that they can distinguish flickering from continuous illumination.

Functional evolution of a cis-regulatory module.

Lack of knowledge about how regulatory regions evolve in relation to their structure-function may limit the utility of comparative sequence analysis in deciphering cis-regulatory sequences. To address this we applied reverse genetics to carry out a functional genetic complementation analysis of a eukaryotic cis-regulatory module-the even-skipped stripe 2 enhancer-from four Drosophila species. The evolution of this enhancer is non-clock-like, with important functional differences between closely related species and functional convergence between distantly related species. Functional divergence is attributable to differences in activation levels rather than spatiotemporal control of gene expression. Our findings have implications for understanding enhancer structure-function, mechanisms of speciation and computational identification of regulatory modules.