Isolation of osteoclasts from Pagetic bone tissue: morphometry and cytochemistry on isolated cells.

Giant osteoclasts and other cells were isolated from Pagetic bone tissue using 0.5 mM ethylene diamine tetraacetic acid on bone samples from 8 patients with Paget's disease. The cell suspension contained osteoclasts and osteoblasts as well as some mononuclear cells such as monocytes. The number of nuclei in isolated osteoclasts (33.85 +/- 20.92 nuclei/osteoclast) correlates fairly well (p less than 0.02) with the number of nuclei counted on histologic sections (15.88 +/- 11.80 nuclei/osteoclast) for samples from each patient. Enzyme histochemistry demonstrated acid phosphatase activity in isolated osteoclasts and in mononucleated cells, such as monocytes. Alkaline phosphatase was detected only in osteoblasts while succinate dehydrogenase was observed in osteoclasts, osteoblasts and monocytes. Esterases, such as nonspecific aliesterase and specific naphthol AS-D acetate esterase, were identified in osteoclasts and in macrophages. Inhibition of specific naphthol AS-D acetate esterase in osteoclasts by addition of sodium fluoride suggests that the enzyme could be of monocytic origin.

[Monitoring the microbiological quality of hemodialysis fluids]. / Surveillance de la qualité microbiologique des liquides en hémodialyse.

Microbial quality of hemodialysis fluids seems to be a major short- and long-term quality criterion for patients receiving high-efficiency dialysis. Ten years of results in Le Mans Dialysis Center of quality monitoring water for hemodialysis, dialysate and more recently, acid concentrate are similar to bibliographic data. Controlling this quality obviously presupposes: the limitation of contaminating feedings from water and from acid concentrate aiming at quasi-sterility and apyrogenicity; and the control of biofilm growth inside monitors, ineluctable in the actual state of the art.