- Malakoplakia With Digestive Tract Involvement in a Pig 30 giugno 2014
Gelmetti, D., Gibelli, L., Gelmini, L., Sironi, G.
Malakoplakia is a rare, granulomatous, inflammatory disease that mimics malignant tumors and can affect any organ. Herein is described a case of malakoplakia in a 10-month-old slaughter pig. Diffuse, pleomorphic, round cell infiltrates, mainly histiocytes, with a tumor-like growth pattern at gross examination, infiltrated the stomach, pancreas, omentum, and mesenteric lymph nodes. The histiocytes and multinucleated giant cells had concentric, target-like inclusions known as Michaelis-Gutmann bodies. Microorganisms were not detected by the periodic acid–Schiff reaction, Ziehl-Neelsen, Gram, and Warthin-Starry staining or by electron microscopic and bacteriologic investigations. Porcine circovirus type 2 and porcine reproductive and respiratory syndrome viruses were not detected by immunohistochemistry in the sections examined.
- Diagnostic Exercise: Suppurative Rhombencephalitis and Meningitis in a Goat 30 giugno 2014
Dill, J. A., Rissi, D. R.
A 1-year-old female Boer goat was presented for necropsy following spontaneous death and history of acute recumbency, nystagmus, and sialorrhea. A swollen area was grossly observed in the brainstem at the level of the pons. On cut surface, the right cerebellar peduncles were expanded by a focal, pale, poorly demarcated, slightly depressed, and soft area of malacia. Microscopically, this area contained diffuse edema and necrosis, with microabscesses, neuronal necrosis, neuronophagia, axonal spheroids, vasculitis, and perivascular accumulations of lymphocytes, plasma cells, macrophages, and neutrophils. The diagnosis was based on the morphologic findings, fluorescent antibody test results, and special staining.
- Congenital Cutaneous Histiocytosis in a Piglet 30 giugno 2014
Helie, P., Kiupel, M., Drolet, R.
A 2-week-old crossbred male piglet with numerous congenital, variably sized macules, plaques, and papules distributed all over the body was submitted for necropsy. Significant gross and histological lesions were restricted to the skin. On light microscopic examination, these cutaneous lesions corresponded to dermal and/or subcutaneous masses composed of spindle-shaped to round cells that multifocally contained hemosiderin; epidermotropism was not observed. Immunohistochemically, the neoplastic cells were strongly positive for CD204; moderately positive for CD163, lysozyme, and vimentin; and negative for Mac 387, α-1-antitrypsin, S-100 protein and E-cadherin; frozen tissues were not available for CD1a and CD11c. Transmission electron microscopic examination of sections from formalin-fixed tissues did not reveal Birbeck’s granules. The clinical, morphological, and immunohistochemical results were consistent with a congenital cutaneous histiocytosis of non-Langerhans cell origin. The condition most resembled juvenile xanthogranuloma in humans, a generally skin-limited non-Langerhans histiocytic disorder that can be congenital. Cutaneous and/or systemic histiocytic disorders are well characterized in dogs and have been described in cats, and a case with some similarities to ours has been reported in a neonatal piglet, but this is to our knowledge the first immunohistochemically supported report of histiocytosis in the pig and congenital histiocytosis in animals.
- Immunohistochemical Vascular Factor Expression in Canine Inflammatory Mammary Carcinoma 30 giugno 2014
Camacho, L., Pena, L., Gil, A. G., Martin-Ruiz, A., Dunner, S., Illera, J. C.
Human inflammatory breast carcinoma (IBC) and canine inflammatory mammary carcinoma (IMC) are considered the most malignant types of breast cancer. IMC has similar characteristics to IBC; hence, IMC has been suggested as a model to study the human disease. To compare the angiogenic and angioinvasive features of IMC with non-IMC, 3 canine mammary tumor xenograft models in female SCID mice were developed: IMC, comedocarcinoma, and osteosarcoma. Histopathological and immunohistochemical characterization of both primary canine tumors and xenografts using cellular markers pancytokeratin, cytokeratin 14, vimentin, and α-smooth muscle actin and vascular factors (VEGF-A, VEGF-D, VEGFR-3, and COX-2) was performed. Tumor cell proliferation index was measured by the Ki-67 marker. The xenograft models reproduced histological features found in the primary canine tumor and preserved the original immunophenotype. IMC xenografts showed a high invasive character with tumor emboli in the dermis, edema, and occasional observations of ulceration. In addition, compared with osteosarcoma and comedocarcinoma, the IMC model showed the highest vascular factor expression associated with a high proliferation index. Likewise, IMC xenografts showed higher COX-2 expression associated with VEGF-D and VEGFR-3, as well as a higher presence of dermal lymphatic tumor emboli, suggesting COX-2 participation in IMC lymphangiogenesis. These results provide additional evidence to consider vascular factors, their receptors, and COX-2 as therapeutic targets for IBC.
- Tumor Microenvironment Regulates Metastasis and Metastasis Genes of Mouse MMTV-PymT Mammary Cancer Cells In Vivo 30 giugno 2014
Werbeck, J. L., Thudi, N. K., Martin, C. K., Premanandan, C., Yu, L., Ostrowksi, M. C., Rosol, T. J.
Metastasis is the primary cause of death in breast cancer patients, yet there are challenges to modeling this process in vivo. The goal of this study was to analyze the effects of injection site on tumor growth and metastasis and gene expression of breast cancer cells in vivo using the MMTV-PymT breast cancer model (Met-1 cells). Met-1 cells were injected into 5 sites (subcutaneous, mammary fat pad, tail vein, intracardiac, and intratibial), and tumors and metastases were monitored using bioluminescent imaging and confirmed with gross necropsy and histopathology. Met-1 tumors were analyzed based on morphology and changes in gene expression in each tissue microenvironment. There were 6 permissible sites of Met-1 tumor growth (mammary gland, subcutis, lung, adrenal gland, ovary, bone). Met-1 cells grew faster in the subcutis compared to mammary fat pad tumors (highest Ki-67 index). Morphologic differences were evident in each tumor microenvironment. Finally, 7 genes were differentially expressed in the Met-1 tumors in the 6 sites of growth or metastasis. This investigation demonstrates that breast cancer progression and metastasis are regulated by not only the tumor cells but also the experimental model and unique molecular signals from the tumor microenvironment.
- Epithelial Urinary Bladder Tumors From Cows With Enzootic Hematuria: Structural and Cell Cycle-Related Protein Expression 30 giugno 2014
Cota, J. B., Carvalho, T., Pinto, C., Peleteiro, M. C.
Thirty-nine epithelial bladder tumor samples from 37 animals affected with bovine enzootic hematuria (BEH) were selected for immunohistochemical studies. The expression of structural proteins such as uroplakin III (UPIII) and cytokeratin 7 (CK7) and the cell cycle–related proteins cyclin D1 and p53 were evaluated in urothelial papillomas and carcinomas. Loss of UPIII and CK7 expression was seen in both high-grade and high-stage urothelial carcinomas (P < .001 and P < .02). Cyclin D1 expression showed no statistically significant association with grade or stage. In contrast, p53 immunoreactivity was positive in high-grade and high-stage carcinomas (P < .05 and P < .01), confirming its association with the highest malignant behavior of the bladder tumors in BEH.
- Necrosuppurative Orchitis and Scrotal Necrotizing Dermatitis Following Intratesticular Administration of Zinc Gluconate Neutralized With Arginine (EsterilSol) in 2 Mixed-Breed Dogs 30 giugno 2014
Forzan, M. J., Garde, E., Perez, G. E., Vanderstichel, R. V.
Intratesticular injection of EsterilSol (zinc gluconate neutralized with arginine) is a chemical sterilant for male dogs sometimes used in population control campaigns. Adverse reactions have been reported in 1% to 4% of treated dogs, but detailed histomorphologic descriptions are lacking. During a behavioral study conducted in the Chilean Patagonia in 2012, severe necrosuppurative orchitis and ulcerative dermatitis were observed in 2 of 36 (6%) dogs sterilized with EsterilSol according to the manufacturer’s instructions. Reactions were noted on days 8 and 7 postinjection and required scrotal ablation on days 8 and 13, respectively; neither reaction was associated with the injection site. Although self-trauma following administration may have contributed, the cause of the adverse reactions is uncertain. EsterilSol is a relatively uncomplicated method to sterilize male dogs, but the occurrence of severe adverse reactions several days after administration emphasizes the need for the provision of long-term monitoring and veterinary care during sterilization campaigns using this product.
- N-cadherin Expression in Feline Mammary Tumors Is Associated With a Reduced E-cadherin Expression and the Presence of Regional Metastasis 30 giugno 2014
Buendia, A. J., Penafiel-Verdu, C., Navarro, J. A., Vilafranca, M., Sanchez, J.
The cadherin family of adhesion molecules regulates cell-cell interactions. N-cadherin is expressed by neural and fibroblast cells but not by normal epithelial cells. In human medicine, the role of N-cadherin in breast cancer remains controversial, but some studies have described the switch from E-cadherin to N-cadherin as a critical step in the malignant progression of neoplastic cells. The present study was carried out on 160 feline mammary tumors (21 adenomas and 139 carcinomas). The relationship between the immunohistochemical expression of N-cadherin in neoplastic epithelial cells and 2 established prognostic factors such as regional metastasis and tumor grade was examined. The results of the study showed a statistically significant relation between the expression of N-cadherin and the 2 prognostic factors, and also a reduced expression of E-cadherin in tumors that expressed N-cadherin.
- Phenotypic Characterization of the KK/HlJ Inbred Mouse Strain 30 giugno 2014
Berndt, A., Sundberg, B. A., Silva, K. A., Kennedy, V. E., Richardson, M. A., Li, Q., Bronson, R. T., Uitto, J., Sundberg, J. P.
Detailed histopathological diagnoses of inbred mouse strains are important for interpreting research results and defining novel models of human diseases. The aim of this study was to histologically detect lesions affecting the KK/HlJ inbred strain. Mice were examined at 6, 12, and 20 months of age and near natural death (ie, moribund mice). Histopathological lesions were quantified by percentage of affected mice per age group and sex. Predominant lesions were mineralization, hyperplasia, and fibro-osseous lesions. Mineralization was most frequently found in the connective tissue dermal sheath of vibrissae, the heart, and the lung. Mineralization was also found in many other organs but to a lesser degree. Hyperplasia was found most commonly in the pancreatic islets, and fibro-osseous lesions were observed in several bones. The percentage of lesions increased with age until 20 months. This study shows that KK/HlJ mice demonstrate systemic aberrant mineralization, with greatest frequency in aged mice. The detailed information about histopathological lesions in the inbred strain KK/HlJ can help investigators to choose the right model and correctly interpret the experimental results.
- MicroRNAs: History, Biogenesis, and Their Evolving Role in Animal Development and Disease 30 giugno 2014
Bhaskaran, M., Mohan, M.
The discovery of microRNAs (miRNAs) in 1993 followed by developments and discoveries in small RNA biology have redefined the biological landscape by significantly altering the longstanding dogmas that defined gene regulation. These small RNAs play a significant role in modulation of an array of physiological and pathological processes ranging from embryonic development to neoplastic progression. Unique miRNA signatures of various inherited, metabolic, infectious, and neoplastic diseases have added a new dimension to the studies that look at their pathogenesis and highlight their potential to be reliable biomarkers. Also, altering miRNA functionality and the development of novel in vivo delivery systems to achieve targeted modulation of specific miRNA function are being actively pursued as novel approaches for therapeutic intervention in many diseases. Here we review the current body of knowledge on the role of miRNAs in development and disease and discuss future implications.