G. A. Ramírez

Cross-reactivity of human and bovine antibodies in striped dolphin paraffin wax-embedded tissues.

This study evaluates the cross-reactivity of seven anti-human and one anti-bovine antibodies in formalin-fixed, paraffin-embedded tissue samples of liver and mesenteric lymph nodes of 13 striped dolphins (Stenella coeruleoalba). Four antibodies (CD3, IgG, lysozyme and S100 protein) reacted with striped dolphin lymph nodes in a similar pattern to that observed in the species of origin. The anti-human MHC class II mAb reacted strongly with macrophages and dendritic-like cells of striped dolphins, whereas a small number of lymphocytes were labelled with this antibody. These antibodies were used to study the immunophenotype of the inflammatory infiltrated in non-specific chronic reactive hepatitis (eight cases) and chronic parasite cholangitis (two cases) and normal liver (three cases) of striped dolphins. Non-specific chronic reactive hepatitis was composed of inflammatory infiltration of CD3+ T lymphocytes and IgG+ plasma cells in portal spaces and hepatic sinusoids. Lymphonodular aggregates observed in chronic parasitic cholangitis showed a cellular distribution similar to that found in lymph node cortex, including the presence of S100+ and MHC class II+ dendritic-like cells in lymphoid follicles and interfollicular areas. This result suggests that those inflammatory infiltrates are highly organised to enhance antigen presentation to B and T cells.

Expression of Maspin in Mammary Gland Tumors of the Dog

Maspin is a serine protease inhibitor that inhibits tumor invasion and metastasis in human breast cancer and is consistently expressed by mammary myoepithelial cells (MECs). To analyze the value of maspin as a marker of the MEC layer of the normal and tumoral canine mammary gland, the immunohistochemical expression of maspin was studied in formalin-fixed tissues from 55 benign and malignant tumors (40 tumors also contained the surrounding normal mammary gland) using a commercially available monoclonal antibody. Periacinar and periductal MECs of all 40 normal mammary glands were stained by the anti-human maspin monoclonal antibody, and immunoreactivity was observed in the nucleus and cytoplasm of these cells. In addition, maspin was found in 53 (98%) of the tumors studied, reacting with the MECs in 100% of benign tumors and 93% of malignant tumors and to the epithelial cells of 16% of benign and 73% of malignant tumors. In the MEC compartment, immunoreactivity was observed in the cytoplasm of hypertrophic MECs, fusiform MECs, stellate MECs, rounded (myoepithelial) cells, and chondroblasts. In the epithelial cell compartment, immunoreactivity was observed in the cytoplasm of cells with and without squamous differentiation. Stromal myofibroblasts were unreactive. Maspin appears to be a very sensitive marker of the normal and neoplastic myoepithelium that, contrary to smooth muscle differentiation markers, does not stain stromal myofibroblasts. In addition, a subset of neoplastic epithelial cells reacted with the maspin antibody. The relationship between maspin expression in different cellular compartments of canine mammary carcinomas and the biologic aggressiveness of the disease remains to be elucidated.

Lipid-rich Carcinomas of the Mammary Gland in Seven Dogs: Clinicopathologic and Immunohistochemical Features

Lipid-rich carcinomas occurred in seven female dogs. Affected dogs were purebred (all but one), intact (all but one), and between 4 and 13 years of age. Five of them had a history of parity, one had pseudopregnancy, and none had received contraceptive steroids. The tumors were single (five cases) or multiple (two cases) well-circumscribed masses of different sizes (varying from 1 to 6 cm in diameter), composed of solid nests and cords of tumor cells separated by a moderate amount of stroma. The tumor cells contained either multiple and small or large and solitary vacuoles that pushed the nucleus to the periphery of the cell (signet-ring cell). A glandular epithelial immunophenotype (cytokeratins 5 and 8 and 8 and 18) was observed in the majority of tumor cells. All tumors lacked both estrogen and progesterone receptors, and five out of seven tumors gave rise to local recurrence and proximal or distant metastases or both.

Testicular necrosis caused by Mesocestoides species in a dog

protein 3AB as the antigen and application to an eradication program. Journal of Clinical Microbiology 40, 2843-2848 DUNN, C. S. & DONALDSON, A. I. (1997) Natural adaptation to pigs of a Taiwanese isolate of foot-and-mouth disease virus. Veterinary Record 141, 174-175 LIAO, P. C., CHEN, S. P., YANG, P. C., CHEN, C. M., JONG, M. H., HSU, T. W. & CHUNG, W. B. (2003) Surveillance of serum neutralisation antibodies to foot-and-mouth disease virus in pigs after intensive vaccination in Taiwan. Taiwan Veterinary Journal 29, 46-52 LIN, Y. P., JONG, M. H., JU, W. J., LIN,Y. L., CHEN, C. L., LU, C. C., HUANH, T. S. & LIN, S. Y. (2000) Experiments on the susceptibility of swine, cattle, goats, ringdoves and rats to foot-and-mouth disease virus O/TWN/97. Proceedings of the 11th Congress of the Federation of Asian Veterinary Association. Taipei, Taiwan, November 27 to 30, 2000. p 278 MACKAY, D. K. J., FORSYTH, M. A., DAVIES, P. R., BERLINZANI, A., BELSHAM, G. J., FLINT, M. & RYAN, M. D. (1998) Differentiating infection from vaccination in foot-and-mouth disease using a panel of recombinant, non-structural proteins in ELISA. Vaccine 16, 446-459 SALT, J. S. (1993) The carrier state in foot-and-mouth disease an immunological review. British Veterinary Journal 149, 207-223 SHIEH, H. K. (1997) The FMD situation in Taiwan. Journal ofthe Chinese Society of Veterinary Science 23, 395-402 SORENSEN, K. J., MADSEN, K. G., MADSEN, E. S., SALT, J. S., NQINDI, J. & MACKAY, D. K. J. (1998) Differentiation of infection from vaccination in foot-and-mouth disease by the detection of antibodies to the non-structural proteins 3D, 3AB and 3ABC in ELISA using antigens expressed in baculovirus. Archives of Virology 143, 1-16 YANG, P. C., CHU, R. M., CHUNG, W. B. & SUNG, H. T. (1999) Epidemiological characteristics and financial costs of the 1997 foot-andmouth disease epidemic in Taiwan. Veterinary Record 145, 731-734

Cartilaginous Tumors of the Larynx and Trachea in the Dog: Literature Review and 10 Additional Cases (1995-2014).

Cartilaginous tumors of the larynx and trachea are uncommon in the dog. The authors describe 10 cases diagnosed between 1995 and 2014 and review 16 cases in the literature. Seven of our cases were tracheal and 3 were laryngeal. Two of the laryngeal tumors were chondromas, which have not been previously reported in this site. The third laryngeal tumor was a myxochondroma. Of the 7 tracheal tumors, 6 arose from the ventral tracheal wall, including 2 that were extraluminal. Tracheal tumor types included chondrosarcoma (n = 3), chondroma (n = 2), and osteochondroma (n = 2). All of the laryngeal tumors and 5 of 7 of the tracheal tumors occurred in adult dogs (aged 5–11 years). The 2 tracheal osteochondromas were in young dogs (3–4 months) and were intrathoracic, while the remaining tracheal tumors were cervical. Surgical excision had a good outcome in most cases. Combining our 10 cases with the 16 previously reported cases showed that 6 (27%) of the affected dogs were Arctic breeds (Alaskan Malamute or Siberian Husky) suggesting a predisposition in this type of dog.

Morphologic and immunohistochemical features of Merkel cells in the dog.

Merkel cells (MCs) are specialized skin receptors characterized by their particular location and close association with nerve terminals. They also are cells with a presumptive neuroendocrine function and are considered as part of the diffuse neuroendocrine system. By using commercially available monoclonal and polyclonal antibodies in samples of dog skin, MCs were properly distinguished from other clear cell types in the epidermis. They expressed cytokeratins 7, 8, 20, EpCAM, NSE, CGA, SYN, S100 protein, and NF, presented diverse cytological features and arrangements depending on the location considered, and showed pronounced heterogeneity with markedly different expression and distribution patterns for antibodies used. Anti-CK20 presented as the most reliable and specific antibody for their identification. The present study increases our knowledge of MCs and establishes a basis for future studies of the role(s) of the MCs in diseased tissues of the dog skin, including the cutaneous neuroendocrine (Merkel cell) tumour.

Naturally Acquired Visceral Leishmaniosis in a Captive Bennett’s Wallaby (Macropus rufogriseus rufogriseus)

A high prevalence of leishmaniosis has been reported from an increasing number of domestic and wild mammals around the world. In Australian macropods, Leishmania spp infection has been occasionally described in its cutaneous form only. The purpose of this report is to present a case of fatal visceral leishmaniosis in a captive Bennett’s wallaby in Madrid, Spain, which was investigated by detailed macroscopic, histologic, and immunohistochemical examinations.

Left Ventricular Outflow Tract-Right Atrial Communication (Gerbode Type Defect) Associated with Bacterial Endocarditis in a Dog

Left ventricular (LV) outflow tract-right atrial (RA) communication associated with bacterial endocarditis is described in a 6-year-old intact male Great Pyrenees dog with a 4- to 5-day history of fever, lethargy, weight loss, severe regenerative anemia, and asplenia. Typical vegetative mural endocardial lesions were observed grossly. Histologic evaluation revealed small gram-negative coccobacilli that were consistent with Bordetella avium-like organisms. These bacteria were associated with severe endocardial inflammation characterized by neutrophilic infiltration, extensive necrosis of endocardium, and fibrin deposition. LV-RA shunt (Gerbode defect) is a rare cardiac defect in humans that can be either congenital or, more rarely, secondary to septic endocarditis, valve replacement procedures, or thoracic trauma. B. avium-like organisms causing septicemia and endocarditis in immunocompromised and asplenic human patients have been described. To our knowledge, no previous descriptions of Gerbode defect associated with bacterial endocarditis in domestic animals have been reported in veterinary literature.

Clinical, histopathological and epidemiological study of canine straelensiosis in the Iberian Peninsula (2003–2007)

Straelensiosis is a relatively new disease described in dogs and produced by a trombiculid larva known as Straelensia cynotis. Few cases have been reported in the English literature. Straelensiosis has been observed in Southern France and Northern Portugal causing a distinctive nodular dermatitis. The present study describes the clinical, histopathological and epidemiological features of 19 cases diagnosed as straelensiosis in the north of Spain and Portugal (2003-2007). A follow-up of the animals after diagnosis was carried out. Differences with previously described cases were observed, especially concerning epidemiology and histopathology. The grade of response to different treatments and new microscopic features are discussed. The study concludes that S. cynotis can cause a nodular dermatitis in rural and hunting dogs in Spain and Portugal and is associated with particular seasonal and geographical factors.

Multiple primary digital apocrine sweat gland carcinosarcoma in a cat

under the epithelial cells (Fig 2), and extensive areas of pro-liferation of neoplastic mesenchymal cells. These cells hadspindle to round morphology, but sometimes showed angu-lar borders. They had hyperchromatic, eccentric nuclei anddark-staining cytoplasm; their mitotic activity was moderate.The neoplastic cells produced, and entrapped themselves in,irregular islands of osteoid matrix. Vascular invasion byemboli of tumour cells was observed on several occasions.Ulceration of the epidermis was frequent, and was the resultof superficial dermal tumour invasion.To characterise the immunophenotype of the neoplasticcells,antibodies to cytokeratins (Cks) 5 and 8 (clone