1,193 research outputs found
Electrochemical C(sp3)-H functionalization of ethers via hydrogen-atom transfer by means of cathodic reduction
: The chemo- and stereoselective electrochemical allylation/alkylation of ethers is presented via a C(sp3)-H activation event. The electrosynthetic protocol enables the realization of a large library of functionalized ethers (35 examples) in high yields (up to 84%) via cathodic activation of a new type of redox-active carbonate (RAC), capable of triggering HAT (Hydrogen-Atom-Transfer) events through the generation of electrophilic oxy radicals. The process displayed high functional group tolerance and mild reaction conditions. A mechanistic elucidation via voltammetric analysis completes the study
Diurnal cortisol and obesity in adolescents with and without Down syndrome
BackgroundThe prevalence of obesity in adolescents with Down syndrome (DS) far exceeds that in the general population. Cortisol, an adrenal hormone, can be obesogenic when dysregulated. However, the diurnal patterns of this hormone have not been examined among individuals with DS. Variations in adiposity may also mediate cortisol regulation. This study sought to examine diurnal cortisol patterns in adolescents with DS as well as associations between cortisol function and obesity.MethodA total of 32 adolescents, including 16 with DS and 16 controls with typical development (TD) of similar sex, age and Tanner pubertal stage (P > 0.05), participated in this preliminary study. Participants completed a dualâenergy Xâray absorptiometry scan to measure body composition and collected saliva samples for cortisol measurements in the morning, afternoon and night. Linear mixed models with random intercepts and repeated measures were used to examine the daily trajectory of logâtransformed cortisol concentrations between adolescents with and without DS. A second model examined the interaction between DS and presence of elevated body fatness.ResultsAdolescents with DS had higher morning cortisol concentrations (intercept = 0.37 Όg/dL), but this was not significantly different than in TD (0.35 Όg/dL, P = 0.16). Cortisol significantly declined across hours (b = â0.026 Όg/dL/h, P  0.05; d = 0.30).ConclusionsThis study is the first to examine diurnal cortisol in DS but is limited in sample size. These preliminary findings suggest that diurnal cortisol patterns are not significantly different between adolescents with DS and TD and that cortisol levels are not associated with adiposity in this population. Despite these nonâsignificant differences, youth with DS continue to be an âatâriskâ population for paediatric obesity in need of clinical intervention.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151976/1/jir12682_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151976/2/jir12682.pd
- âŠ