Hematoxylin eosin

Rats were anesthetized by intraperitoneal injection with a mixture of Zoletil 100 (Virbac) and Rometar (Bioveta) at a ratio of 1:4 (10 mg/kg) and transcardially perfused with 10 ml cold 0.9% NaCl saline followed by 20 ml cold fixative (4% paraformaldehyde in 0.1 M phosphate buffer, pH 7.2). The brains were immediately removed and post-fixed for 12 h at 4°C in fresh buffered 4% paraformaldehyde. After rinsing, the brains were processed and embedded in paraffin, according to standard embedding techniques. Coronal cuts of the paraffin-embedded brain were made until the tumor was exposed, after which 7-µm slices were obtained using a microtome. All three areas of interest (tumor, near-tumor area and symmetric area of the opposite hemisphere) were present on each slide. The near-tumor area was defined as the 200-µm of tissue around the tumor edge. Paraffin-embedded brain sections (7 µm) were stained with hematoxylin-eosin (Bio Optica, Milano, Italy), according to the standard procedure for morphological tissue analysis.

All of the specimens were fixed in 10% buffered neutral formalin and embedded in paraffin. To visualize myocardial lesions at different levels, the entire heart was cut into four segments from apex to the base. The segments were embedded in paraffin and 4-µm thickness cross-sections were cut from each segment.
The slides were stained with Hematoxylin–Eosin (Bio-optica, Milano, Italy) for the evaluation of the tissues’ histological features. The slides were examined under light microscope for myonecrosis, inflammatory cell infiltration, and edema. A minimum of 10 fields for each slide were examined and graded for severity of changes using scores on a scale of severe (+ + +), moderate (+ +), mild (+), and nil (−) (16 (link)).