Immunohistochemical localization of vimentin, glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), neuron-specific enolase (NSE) were performed to confirm the canine schwannoma diagnosed histologically. Biopsy samples from skin masses occurred on a 6 year old female dog and a 13 year old female dog were used for immunohistochemical analysis. Histologically, the tumor tissues showed the characteristics of schwannoma mainly composed of predominantly fusiform or spindle cells. The cells are arranged in small interwoven bundles with intervening fibrous and mucinous stroma that imitate a herringbone pattern. The cell nuclei have an elongated, wavy, buckled appearnce and closely bunched together. In high magnification, mitotic figure, nuclear hyperchromatism, pleomorphism and poorly defined cytoplasms were noted. the vimentin was highly expressed in the cytoplasm of all neoplastic cells. Positive reactions against NSE and GFAP, widely used to suggest a neural origin of cell types, are observed in cytoplasms of tumor cells. These results can be used as a reference data for definitive diagnosis of canine schwannoma.

Phytic acid (PA) (Inositol hexaphosphate, IP6) is a naturally occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. In the present study, the preventive effects of PA on colon carcinogenesis were investigated. Six-week old Fisher 344 male rats were fed a AIN-93G purified diet and PA (0.5% or 2% PA in water) for 8 weeks. The animals received two (1st and 2nd week) injections of azoxymethane (AOM, 15 mg/kg b.w.) to induce colonic aberrant crypt foci (ACF). After sacrifice, the total numbers of aberrant crypts (AC) and ACF in colonic mucosa were examined after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM induced the total numbers of 142.3 ± 22.3 ACF/colon and 336.6 ± 55.1 AC/colon. PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dosedependent manner. The numbers of ACF/colon and AC/colon by PA at the dose of 0.5% were 124.4 ± 28.5 and 302.7 ± 67.3, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to 109 ± 18.1 and 254.8 ± 50.6, respectively (p < 0.01). Especially, 2% PA significantly reduced the number of large ACF ( ≥ 4 AC/ ACF) from 26.8 ± 6.2 ACF/colon to 15 ± 6.7 ACF/colon (p < 0.01). Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. These findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in the F344 rat.

A 13-year-old, male mixed breed dog was presented to Veterinary Medical Center, Chungbuk National University for diagnosis and treatment of enlarged mass in right inguinal region. On hematological test, monocytes and neutrophils were slight increased, but other hematological values were normal. On radiological finding, opacity and size of mass in right inguinal region were increased. The mass and testis were removed surgically. Removed mass was oval-shpae and bulky with 5.6×7.6×5.2 cm. Histopathological finding of the mass revealed large and round to polyhedral cells and it was diagnosed as malignant seminoma. That was diffuse type seminoma near to malignant tumor without metastasis. During the follow-up for 13 months, patient showed normal contition without recurrence.