Interaction of liposomes with subviral particles of poliovirus type 2 and rhinovirus type 2.

Subviral particles ("A particles") were produced from rhinovirus type 2 by treatment with acid and from poliovirus type 2 by incubation at 37 degrees C in a low-ionic-strength buffer. A particles, but not virions, adsorbed to liposomes. It is proposed that these reactions may provide an in vitro model for two early steps of infection.

Microdetermination of ergocalciferol (vitamin D2) in pharmaceutical preparations by differential spectroscopy using trifluoroacetic acid in the absence of vitamin A.

A differential spectroscopy method for the determination of microgram quantities of ergocalciferol, using trifluoroacetic acid and hydrogen peroxide, was applied to commercially available pharmaceutical preparations. Tablets were powdered and extracted with methanol after being made basic with diethylamine. The methanol was concentrated, chloroform was added, and the mixture was chromatographed on neutral alumina using chloroform as the eluent.

Early alteration of poliovirus in infected cells and its specific inhibition.

HeLa cells infected with radioactive poliovirus type 2 were disrupted with ultrasonic treatment, followed by addition of a non-ionic detergent. Two types of virus particles were found to sediment at 80 to 90% the rate of native virus. The first of these appeared to be a complex of native virus particles and membrane components, since treatment with 0-2% SDS released infectious native particles.