Urinary adenosine excretion in patients receiving amphotericin B

Polyene Antibiotics Physical Chemistry and Their Effect on Lipid Membranes; Impacting Biological Processes and Medical Applications

This review examined a collection of studies regarding the molecular properties of some polyene antibiotic molecules as well as their properties in solution and in particular environmental conditions. We also looked into the proposed mechanism of action of polyenes, where membrane properties play a crucial role. Given the interest in polyene antibiotics as therapeutic agents, we looked into alternative ways of reducing their collateral toxicity, including semi-synthesis of derivatives and new formulations. We follow with studies on the role of membrane structure and, finally, recent developments regarding the most important clinical applications of these compounds.

Release of netilmicin and vancomycin from cancellous bone

First, we studied the effect of the following variables used for netilmicin- and vancomycin-impregnation of cancellous bone: a) antibiotic concentration of the impregnation fluid, b) time used for impregnation, c) pH of the impregnation fluid, d) the degree of bone morselizing and e) antibiotic combination. An increase in the antibiotic concentration of the impregnation fluid increased the amount of antibiotics released from bone. In addition, the amount of vancomycin eluted was also dependent on the time used for impregnation. The fraction of the total amount of netilmicin and vancomycin released after 24 h was 80% and 30%, respectively. More netilmicin and vancomycin were eluted from bone impregnated with antibiotics at pH 7 than the amount eluted from bone impregnated at pH 3. More netilmicin was eluted from fine morselized bone than from coarse morselized bone. By combining netilmicin and vancomycin in the impregnation fluid, the release of vancomycin was reduced. Secondly, we analyzed if the release of antibiotics from bone was complete: 99.9% of the total amount of netilmicin adsorbed to the bone was released by elution during 6 weeks. Finally, after implantation of netilmicin-impregnated bone in rabbit femur condyle, we measured netilmicin and vancomycin in serum: peak serum values of netilmicin were 4.2 (3.7-4.7) mg/L 2-3 h postoperatively.