Figure 1.

Structural and ultrastructural (electron microscopy) analyses of human brain tissue sections obtained from the ependymoma (case 9945) and meningitis cases. Aa. H&E staining of paraffin embedded wax tissue sections; original magnification, ×200. The presence of perivascular rosette (Ro) formation is typical of an ependymoma. Ab. Electron micrographs taken of the araldite-enhanced ependymoma cells. Original magnification, ×13500; inset: original magnification, × 23000. The white arrows indicate junction complexes between cells and the black arrows indicate microvilli (see inset). These structures reveal key characteristics of ependymal cells. Ba, Bb, Meningitis cases. Original magnification, ×100. Choroid plexus (a) and ependyma (Ep) (b) show a continuous layer of intact epithelial cells despite the presence of neutrophils (PMN) inside the ventricle (particularly in panel Bb, see inset, magnification ×1000). V, vessel; Cp, choroid plexus; Ep, ependymal layer.