Population Pharmacokinetics of Single Bolus Dose Fentanyl in Obese Children.

Background: Childhood obesity is a significant problem. Obesity may alter the pharmacokinetics (PKs) of medications. Fentanyl is commonly used for procedural sedation, but there is a paucity of bolus dose fentanyl PK data in obese children.

Profound hypokalemia associated with severe diabetic ketoacidosis.

Hypokalemia is common during the treatment of diabetic ketoacidosis (DKA); however, severe hypokalemia at presentation prior to insulin treatment is exceedingly uncommon. A previously healthy 8-yr-old female presented with new onset type 1 diabetes mellitus, severe DKA (pH = 6.98), and profound hypokalemia (serum K = 1.

Acyclic Stereoselection in the Ortho Ester Claisen Rearrangement.

The ortho ester Claisen rearrangement of trisubstituted allylic alcohols exhibits significant levels of diastereoselection. In E allylic alcohols, a 1,3-diaxial interaction develops in the chairlike transition state leading to the anti isomer, rendering the reaction syn selective by a factor of 3-5 to 1. In Z allylic alcohols, the 1,3-diaxial interaction develops in the transition state leading to the syn isomer, generating an anti:syn selectivity of 6-15 to 1.