1,721,114 research outputs found
Monitoraggio bioptico e biochimico in corso di lipidosi epatica nelle bovine da latte ad elevata produzione.
No full textAn unusual case of fatal Strongyloides stercoralis hyperinfection
No full textA 13-month-old male Yorkshire terrier from Modena (Northern Italy) was submitted to physical examination because of coughing, diarrhea and progressive weight loss, which worsened in the last week of life. Depression and dyspnea were noted on clinical examination. Radiography of the thorax indicated interstitial involvement of the diaphragmatic lobe of the right lung and ultrasound of the abdomen showed a diffuse thickening of the small intestine wall. Blood chemistry was indicative of pan-hypoproteinaemia and low folate and fecal examination revealed numerous Strongyloides stercoralis rhabditiform and vital larvae. The subject died after two days and the anatomo-histopathological and parasitological exams confirmed the morphological features of adult S. stercoralis (a well-known agent of zoonosis). This is the first reported case of Strongyloides in Italy in the dog
Assessment of proliferative activity by anti-PCNA monoclonal antibodies in formalin-fixed, paraffin-embedded samples and correlation with mitotic index
No full textn the present study, the employment of clone PClO inveterinary oncology has been investigated, with regard toimmunoreactivity in dogs and cats and reproducibility of themethod on samples with known and unknown time of fix-ation as often happens in stored material for retrospectiveinvestigations. The percentage of labeled nuclei (PCNA in-dex) was evaluated by computerized image analysis. Twodifferent values of PCNA index were considered: one count-ing as positive only the strongly labeled nuclei (SP-PCNAindex) and the other counting as positive all the labeled nuclei(TP-PCNA index). Both values of PCNA index were com-pared with mitotic index (number of mitoses per 1,000 cells
Proliferative activity assessed by anti-PCNA and Ki67 monoclonal antibodies in canine testicular tumours
No full textThe recent availability of monoclonal antibodies raised against cell cycle nuclear antigens makes possible, by means of immunohistochemical techniques, an easy and quick method of evaluating tumour kinetic activity, in addition to older methods such as measurement of the mitotic index. Some of these antibodies can be used on formalin-fixed paraffin wax-embedded samples, thus allowing the use of archival material. In the present study the proliferative activity of testicular tumours of the dog (seminomas and Sertoli and Leydig cell tumours) was investigated with two monoclonal antibodies to proliferating cell nuclear antigen (PCNA) clone PC10, and Ki67 clone MIB1. The former recognizes a formalin-resistant epitope of PCNA, and MIB1 the same antigen as Ki67 in formalin-fixed, paraffin wax-embedded sections after incubation in a microwave oven. Three parameters of proliferative activity were considered: PCNA and Ki67 indices (percentage of nuclear area positive to PCNA and to Ki67), and mitotic index (number of mitoses per 1000 cells). The PCNA index and Ki67 index revealed a good correlation in linear regression analysis (P<0·001) as did the mitotic index (P<0·01). None of the parameters considered revealed a significant difference in proliferative activity of the three types of tumour (P<0·05—Spearman test), but in both seminomas and Sertoli cell tumours the progression from tubular to diffuse pattern paralleled an increase in growth fraction. It is interesting that some seminomas of the diffuse type, often considered on histological grounds to be the most malignant, showed the highest values of the above-mentioned parameters. © 1994, Academic Press Limited. All rights reserved
Basement membrane components in mammary tumours of the dog and cat
No full textThe distribution of the basement membrane (BM) components, laminin, type IV collagen and type VII collagen were studied immunohistochemically in benign and malignant growths of the mammary epithelium of the dog and cat. Intact BMs were found in benign growths, but in well-differentiated malignant tumours they were generally discontinuous, and missing in poorly differentiated carcinomas. An increase in the histological grade of atypia was accompanied by a more marked disruption or fading of BM. Monoclonal antibody (LH 7.2) proved useful in demonstrating type VII collagen in tumours in which massive proliferation of blood vessels made the evaluation of BM features with antibodies to laminin and type IV collagen difficult. Type VII collagen is present in BM of the mammary epithelium but not under the endothelium of blood vessels; it may therefore enhance the value of BM markers as aids in the study of neoplastic progression. © 1993, Academic Press Limited. All rights reserved
Histochemical and immunohistochemical characterization of canine mammary mucinous carcinoma
No full textMucinous carcinoma is a rare mammary tumour, characterized by intracellular and extracellular mucin. It is still uncertain whether the origin of the mucin is epithelial, myoepithelial or fibroblastic. Eleven canine cases originally classified as mucinous carcinomas were reassessed and compared with myoepithelial nests of mixed tumours. All samples were examined (1) histochemically by the periodic acid-Schiff (PAS) and PAS-diastase methods, and with alcian blue (pH 2.5 and pH 1.0), mucicarmine and Grimelius silver stain, and (2) immunohistochemically for cytokeratin 19, vimentin, α-actin and chromogranin A. This examination revealed that only five of the 11 tumours were genuine mucinous carcinomas. In these five tumours the mucus-secreting cells showed cytoplasmic cytokeratin 19 positivity; the mucus showed PAS-diastase and mucicarmine positivity, and alcianophilia which was stronger at pH 2.5 than at 1.0. The remaining six cases were re-classified as mixed tumours because both mucus and mucus-producing cells shared the following similarities with myoepithelial nests of mixed tumours: vimentin and α-actin cytoplasmic positivity, PAS negativity, alcianophilia both at pH 2.5 and 1.0, and mucicarmine positivity. © 2003 Elsevier Ltd. All rights reserved
La Heat Shock Protein 90 (HSP90) è associata all’evoluzione iperplastica e neoplastica della prostata del cane
No full textThe dog represents an important animal model for studying the human prostatic diseases, being exposed to the same environmental conditions and being one of the few species in which prostate cancer spontaneously occurs. In this study, we have evaluated the expression of HSP90 – marker of neoplastic transformation, regulating the androgen receptor activity – in canine Benign Prostatic Hyperplasia (BPH) and Prostatic Carcinoma (PCA). IHC has been performed on 24 samples (2 normal tissues, 17 BPH, 5 PCA). HSP90 expression was mild/moderate, mainly perinuclear, in normal tissues, with a progressive increase of staining intensity and diffuse cytoplasmic and nuclear immunoreactivity in BPH, PCA and metastatic lesions. By means of a semiquantitative analysis, grade 3 (≥ 10% - < 50% positive cells/total cells) was assigned to normal tissues, while 82.3% BPH cases and 100% PCA were scored as grade 4 (≥ 50% positive cells). Moreover, multifocal PIN (Prostatic Intraepithelial Neoplasia) and PIA (Proliferative Inflammatory Atrophy) with similar immunoreactivity to PCA were identified among hyperplastic and neoplastic lesions. In conclusion, the high HSP90 expression in our cases demonstrates that this protein could be involved in the sequential steps leading to prostate cancerogenesis and neoplastic evolution. In addition, veterinary pathologists should pay special attention to recognize specific preneoplastic lesions (PIA, PIN) – underestimated in dog – also in those tissues that look benign.[...
Giant Cells in anaplastic mammary carcinoma of the dog and cat
No full textFour uncommon anaplastic mammary carcinomas containing numerous giant cells are described in three dogs and one cat. The giant cells of all cases were studied by means of monoclonal and polyclonal antibodies to detect epithelial (carcinoembryonic antigen and keratin) and mesenchymal (vimentin, lysozyme and S-100 protein) differentiation. Most of them proved to have an epithelial immunophenotype. Ultrastructurally, scattered bundles of tonofilaments but no lysosome-like bodies could be detected. One tumour had an additional, different type of giant cell, which had a benign multinucleated osteoclast-like appearance, gave positive staining for acid phosphatase, had a histiocytic-stromal immunohistochemical pattern, and was, ultrastructurally, multinucleate with irregular folds and no evidence of tonofilaments. In one case some giant cells had an epithelial immunophenotype and others a stromal immunophenotype, even though their histological and ultrastructural features were the same. In the least histologically differentiated tumour the giant cells presented a coexpression of intermediate filaments. This supported the theory that there might be a stem cell origin for most canine mammary tumours. © 1993, Academic Press Limited. All rights reserved
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