0000000000742900
AUTHOR
C. I. Trigoso
DNA fluorescence induced by polymethine cation pyrvinium binding
Pyrvinium is a polymethine cation which shows interesting fluorescence emission and DNA binding properties. In diluted aqueous solution, pyrvinium pamoate induced a bright yellow fluorescence in kinetoplast DNA from Trypanosoma cruzi epimastigotes as well as in chicken erythrocyte nuclei under a wide range of excitations. No fading was observed after mounting in suitable media. Spectroscopic studies on pyrvinium solutions revealed bathochromic and hypochromic shifts in the absorption spectrum of its complex with DNA. A striking enhancement of pyrvinium fluorescence was found in solvents of high viscosity or after binding to DNA. Experimental results and the chemical structure of pyrvinium a…
A barium method for the cytochemical detection of sulfated glycosaminoglycans in mast cells and basophilic leukocytes.
Barium ions precipitate inorganic as well as organic sulfate compounds and they can be detected by a reaction with sodium rhodizonate. In this work, we describe the use of a barium method for the selective demonstration of sulfated glycosaminoglycans in cytoplasmic granules of mast cells and basophilic leukocytes. Methanol-fixed smears of mouse peritoneal mast cells and rat bone marrow basophils were treated with 5% BaCl2 for 10 min, followed by staining with either 0.2% sodium rhodizonate in 50% ethanol for 2 h at 60 degrees C, or 0.01% brilliant green in distilled water for 1 min. Light microscopic observation revealed a strong staining reaction of the cytoplasmic granules of these cell t…