The economic impact of incorporating flexible endoscopy into a community general surgery practice.

Background: Flexible endoscopy is a vital component of gastrointestinal surgery. It has and will replace many of the surgical procedures now commonly performed. Flexible endoscopy, unfortunately, is not an integral part of surgical residency training based on resident operative experience as reported by the Residency Review Committee.

On the relationship between matrix free Mg2+ concentration and total Mg2+ in heart mitochondria.

The matrix free magnesium ion concentration, [Mg2+]m, estimated using the fluorescent probe furaptra, averaged 0.67 mM in 15 preparations of beef heart mitochondria containing an average of 21 nmol total Mg2+ per mg protein. [Mg2+]m was compared with total Mg2+ during respiration-dependent uptake and efflux of Mg2+ and during osmotic swelling.

Regulation of mitochondrial K+/H+ antiport activity by hydrogen ions.

The effect of matrix pH (pHi) on the activity of the mitochondrial K+/H+ antiport has been studied using the fluorescence of 2,7-biscarboxyethyl-5(6)-carboxyfluorescein (BCECF) to monitor pHi and passive swelling in K+ acetate to follow antiport activity. Heart mitochondria suspended in hypotonic K+ acetate in the absence of respiration show an initial delta pH of -0.4 (interior acid) that decays slowly.