Ultrathin frozen sections of yeast cells

Ultrastructural features of the verruciform xanthoma

The verruciform xanthoma, a rare lesion of the oral cavity, was studied by light and electron microscopy. The major cell type associated with the lesion was shown to contain appreciable amounts of lipid and was characterized as a macrophage. It was characteristic of the endothelial cells associated with subepithelial capillaries to exhibit multiple basal laminae. A rather unusual observation was the migration of lipid-filled cells into the stratum germinativum of the overlying epithelium.

Localization of acid phosphatase in protoplasts from Saccharomyces cerevisiae

The localization of acid phosphatase (EC 3.1.3.2) in secreting protoplasts prepared from Saccharomyces cerevisiae is reported for the first time. Using a Gomori technique we were able to show acid phosphatase at those organelles in the protoplasts which are generally involved in the processes of biosynthesis and secretion of glycoproteins in eukaryotic cells.