Hydroxyethyl Methacrylate Combined with Polyethylene Glycol 400 and Water; an Embedding Medium for Routine 1–2 Micron Sectioning

Abstract

Pieces of tissue, with the largest dimension not exceedmg 7 mm, are 6xed and dehydrated by the procedures of choice. Two stock solutions: A, for infiltration; and B, the accelerator, are used in embedding. Formulas: A, SO ml of glycol methacrylate (2-hydroxyethyl methacrylate-Rob and Haas Co., Philadelphia, Pa.) is mixed well with 12 ml of polyethylene glycol (Carbowax) 400 and 8 ml.of water; then 0.27 gm of benzoyl peroxide added, heated to dissolve the peroxide, and allowed to cool to room temperature. B, polyethylene 200 or 400, 15 parts, and N ,N-dimethylaniline, 1 part, mixed thoroughly. Tissues are first infiltrated completely with solution A, then cast in a mixture consisting of 42 parts of A mixed with 1 part of B. Polymerization occurs in 45 min to 3 hr, depending on the temperature. In a water bath at 20 C, the time required was found to be about 3 hr; at 25 C, 1.5 hr; and at 30 C, 45 min. The plastic block can be trimmed easily, and sections 1-2 p thick readily cut. Sections can he attached to slides by water flotation, without adhesive, and should be dried a t room temperature. Staining with aqueous solutions of basic and acid dyes, without removing the embedding matrix, is sharp and brilliant When staining of the matrix by basic dyes occurs, this background stain can be completely removed by differentiating in either 2-butoxyethanol, pure ethanol, or a mixture of the two. A number of histochemical reagents have been found compatible with this embedding procedure.

Some Effects of Diet on the Mitotic Index and the Cell Cycle of the Ruminal Epithelium of Sheep

“…Rumen papillae were fixed overnight in phosphate buffered 4 % formaldehyde, dehydrated through a graded series of ethanol, and embedded in glycol methacrylate (Leduc & Bernhard, 1967). Polymerization of the glycol methacrylage was initiated by chemical activation (Ruddel, 1967 ; f w S P : . * 8 : Determination of mitotic index.…”

Identification of the nuclear factor kappa-beta (NF-kB) in cortical of mice Wistar using Technovit 7200 VCR

“…Thus, the utilization of this particular antigen-antibody reaction can be applied in studies of diverse pathologic conditions and may result in a better understanding of bone tissue behavior. This lack of reactivity in immunohistochemistry protocols likely results from the series of chemical and temperature changes employed during standard nondecalcified section protocols, and have hindered thorough cell specific investigation of bone tissue under physiologic and pathologic conditions (4)(5)(6). The Technovit 7200 VLC ® is a polymer that is widely utilized for the fabrication of bone and bone-biomaterial thin section for histomorphologic and histomorphometric studies following the nondecalcified technique described by Donath and Breuner 1982 (20).…”

Stems of Allium cepa L. contain starch

“…At 7 d intervals, starting on 26 May 1993 and continuing until 26 January 1994, basal plates were fixed in EPA 70 (5% (v/v) of formaldehyde solution 37% GR, 5 % (v/v) of propionic acid, 90 % (v/v) of ethanol 70% GR). Eollowing dehydration in an ethanol series, and embedding in glycolmethacrylate-methyl methacrylate (Ruddell, 1967) microscopic sections (5 /im) from collected samples were stained with periodic acid-Schiff reaction and Lugol's iodine (Chayen & Bitensky, 1991) and tested for starch.…”