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Nanogold Labeling of the Yeast Endosomal System for Ultrastructural Analyses
Published on: July 14, 2014
Gold toning improves the visualization of nucleolar organizer regions in paraffin embedded tissues
B Delahunt1, F A Avallone, J L Ribas
1Department of Genitourinary Pathology, Armed Forces Institute of Pathology, Washington, D.C.
Abstract:
A modification of the silver colloid technique for staining nucleoar organizer regions in paraffin embedded tissues is described. This modification involves the application of a gold toning step with subsequent gold reduction, if necessary, following incubation of sections in the standard silver colloid solution. Silver stained nucleolar organizer regions (AgNORs) in toned sections are more sharply delineated when compared to untoned controls. In high grade tumors the addition of the toning step results in significantly higher AgNOR counts due to the ability to discriminate more easily individual AgNORs in argyrophilic aggregates within the nucleus. It is recommended, because of enhanced visualization, that this modification of the silver colloid technique be used in studies involving quantification of AgNORs in tissue sections.
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