The Peracetic-Orcein-Halmi Stain: A Stain for Connective Tissues

A selective stain useful for the study of connective tissues is described. The stain demonstrates elastic and oxytalan fibers as well as fibrils in mucous connective tissues previously undescribed. Reticular fibers are not stained. The stain may be used on sections that have been fresh frozen or fixed in formalin or ethanol. Sections are deparaffinized, washed in absolute ethanol, oxidized in peracetic acid 30 min, washed in running water, stained in Taenzer-Unna orcein 15 min, 37°C, differentiated in 70% ethanol, washed in running water, stained in Lillie-Mayer alum hematoxylin 4 min, blued in running water, and counterstained 20 sec in a modified Halmi mixture of 100 ml distilled water, 0.2 gm light green SF, 1.0 gm orange G, 0.5 gm phosphotungstic acid and 1.0 ml glacial acetic acid. Sections are rinsed briefly in 0.2% acetic acid in 95% ethanol, dehydrated and mounted.     

Equipment for Simultaneous Processing of Groups of Slides for Radioautography

The equipment consists of commercially available 5-slide plastic grips (obtained from Lipshaw Manufacturing Co., 7446 Central Ave., Detroit, Mich. 48210) and specially designed lightproof exposure boxes to hold the grips. After deparaffinization and hydration, slides are inserted into the grips, dipped in liquid emulsion, drained, and sealed in the exposure box. After exposure, the 5-slide units are removed from the box (in darkness) and inserted into specially made Plexiglas racks that hold four 5-slide units (20 slides). Photographic developing, fixing, and washing are performed by immersing the 20-slide group in fluids contained in 30-slide glass staining dishes (Lipshaw No. 122 dishes). The equipment simplifies darkroom operations and provides means for standardizing the preparation of radioautographs.