Speciation and quantification of thiols by reversed-phase chromatography coupled with on-line chemical vapor generation and atomic fluorescence spectrometric detection: method validation and preliminary application for glutathione measurements in human whole blood.

Background: We developed a sensitive, specific method for the low-molecular-mass thiols cysteine, cysteinylglycine, glutathione, and homocysteine and validated the method for measurement of glutathione in blood.

Methods: The technique was based on reversed-phase chromatography (RPC) coupled on line with cold vapor generation atomic fluorescence spectrometry (CVGAFS). Thiols were derivatized before introduction on the column by use of a p-hydroxymercuribenzoate (PHMB) mercurial probe and separated as thiol-PHMB complexes on a Vydac C4 column.

Respiratory changes in transvalvular flow velocities versus two-dimensional echocardiographic findings in the diagnosis of cardiac tamponade.

Background: The purpose of this study was to compare the sensitivity, specificity and positive predictive value of the respiratory changes in the transvalvular flow velocities to those of right atrial collapse and right ventricular collapse in the diagnosis of cardiac tamponade.

Methods: Standard two-dimensional and Doppler echocardiography were performed with respiratory monitoring in 56 consecutive patients with mild to severe pericardial effusion. Sixteen patients met the clinical criteria for cardiac tamponade and underwent pericardiocentesis or surgical drainage.