Hydrolysis and enzymatic degradation of Novichok nerve agents.

Several parameters of the Novichok nerve agents A230, A232 and A234 were determined. Hydrolysis rates were approximately one to three orders of magnitude slower than G-type nerve agents and approximately zero to two orders of magnitude slower than V-type nerve agents. A230 was the most labile Novichok compound followed by A232 then A234.

An OPAA enzyme mutant with increased catalytic efficiency on the nerve agents sarin, soman, and GP.

The wild-type OPAA enzyme has relatively high levels of catalytic activity against several organophosphate G-type nerve agents. A series of mutants containing replacement amino acids at the OPAA Y212, V342, and I215 sites showed several fold enhanced catalytic efficiency on sarin, soman, and GP. One mutant, Y212F/V342L, showed enhanced stereospecificity on sarin and that enzyme along with a phosphotriesterase mutant, GWT, which had the opposite stereospecificity, were used to generate enriched preparations of each sarin enantiomer.

Once daily, oral, outpatient quinolone monotherapy for low-risk cancer patients with fever and neutropenia: a pilot study of 40 patients based on validated risk-prediction rules.

Background: The objective of this study was to assess the feasibility of empiric, oral, outpatient quinolone monotherapy in 40 adult patients with fever and neutropenia who were at low risk for serious medical complications.

Methods: Patients with breast cancer or sarcoma who presented with fever and neutropenia and were identified as low risk received empiric, oral, quinolone monotherapy (gatifloxacin at a dose of 400 mg once daily). Patients who had a significant source/focus of infection on presentation were excluded.