Reactivity of the Quinone Methide of Butylated hydroxytoluene in Solution

BHT is a common antioxidant in pharmaceutical formulations and when oxidized it forms a quinone methide (QM). QM is a highly reactive electrophilic species which can undergo nucleophilic addition. This research investigated the kinetic reactivity of QM with water at various pH values and in the presence of sodium chloride and phosphate, acetate, and TAPS buffers. The presence of HCl, HClO4, NaOH, NaCl, and phosphate buffers resulted in simple first order kinetics for disappearance of QM and the formation of a single product (OH-adduct); the reaction was subject to strong acid/base catalysis. The presence of acetate and TAPS buffers resulted in complicated kinetics suggesting the formation of an additional product in equilibrium with QM. These results indicate adduct formation with other nucleophilic excipients is likely which has implications for both the drug product impurity profile and specifications. Due to these considerations BHT should be used with caution

Does Gender Moderate Core Deficits in ASD? An Investigation into Restricted and Repetitive Behaviors in Girls and Boys with ASD

Due to the uneven gender ratio of autism spectrum disorders (ASD), girls are rarely studied independently from boys. Research focusing on Restricted and Repetitive Behaviors (RRBs) indicates that above the age of six girls have fewer and/or different RRBs than boys with ASD. In this study we investigated whether girls and boys with ASD demonstrated similar rates and types of RRBs in early childhood, using discrete observational coding from a video-taped play interaction. Twenty-nine girls with ASD were matched to 29 boys based on ASD severity. While boys in our sample demonstrated a greater frequency of RRBs, this was not significant and our findings indicate that girls and boys under five are more similar than dissimilar on this core deficit. However our data also revealed a trend toward gender-differential growth trajectories – a finding worthy of further investigation in larger samples