Maternal protein restriction during the lactation period disrupts the ontogenetic development of behavioral traits in male Wistar rat offspring.

Neonatal undernutrition in rats results in short- and long-term behavioral and hormonal alterations in the offspring. It is not clear, however, whether these effects are present since the original insult or if they develop at some specific age later in life. Here, we assessed the ontogenetic profile of behavioral parameters associated with anxiety, exploration and memory/learning of Wistar rat offspring that were subjected to protein malnutrition during lactation. Dams and respective litters were separated into two groups: (1) protein-restricted (PR), which received a hypoproteic chow (8% protein) from birth to weaning [postnatal day (PN) 21]; (2) control (C), which received normoproteic chow. Offspring's behaviors, corticosterone, catecholamines, T3 and T4 levels were assessed at PN21 (weaning), PN45 (adolescence), PN90 (young adulthood) or PN180 (adulthood). PR offspring showed an age-independent reduction in the levels of anxiety-like behaviors in the Elevated Plus Maze and better memory performance in the Radial Arm Water Maze. PR offspring showed peak exploratory activity in the Open Field earlier in life, at PN45, than C, which showed theirs at PN90. Corticosterone was reduced in PR offspring, particularly at young adulthood, while catecholamines were increased at weaning and adulthood. The current study shows that considerable age-dependent variations in the expression of the observed behaviors and hormonal levels exist from weaning to adulthood in rats, and that protein restriction during lactation has complex variable-dependent effects on the ontogenesis of the assessed parameters.

Solid Carcinoma of the Canine Mammary Gland: a Histological Type or Tumour Cell Arrangement?

Mammary neoplasms are the most frequently diagnosed tumours in female dogs and are classified into various histological types, including solid carcinomas. We proposed a subclassification of solid carcinomas based on morphological and immunohistochemical characteristics, and correlated the subtypes with prognostic factors. A total of 135 cases of solid mammary carcinoma were selected from 3,400 canine mammary neoplasms in the archives of the Laboratory of Comparative Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil. Epidemiological and survival data were obtained, and immunolabelling for chromogranin A, pancytokeratin, cytokeratin 14, Ki67 and p63 was performed. Solid carcinomas were classified into six subgroups: malignant adenomyoepithelioma (68/135), carcinoma with solid pattern (22/135), malignant myoepithelioma (16/135), basaloid carcinoma (14/135), neuroendocrine carcinoma (10/135) and solid papillary carcinoma (5/135). Shorter survival time was associated with the presence of lymphatic invasion (P = 0.009) in the initial clinical staging (I-III). When considering all clinical stages (I-V), vascular invasion (P <0.001) and the presence of regional metastasis (P = 0.004) were important prognostic factors. Basaloid carcinoma and solid papillary carcinoma did not reach the median survival time for early-stage cases, and malignant myoepithelioma had the highest median survival in advanced stages. Carcinoma with a solid pattern was associated with a higher number of regional metastases. Distinguishing the various histological and immunophenotypic subtypes that exhibit a solid arrangement, using histological and immunohistochemical criteria, is essential for understanding the behaviour of these neoplasms and for the selection of more appropriate and specific therapies.

Canine mammary cancer tumour behaviour and patient survival time are associated with collagen fibre characteristics.

Precise diagnosis and prognosis are key in prevention and reduction of morbidity and mortality in all types of cancers. Here we show that changes in the collagen fibres in the main histological subtypes of canine mammary gland carcinomas are directly associated with the tumour behaviour and the animal survival time and could become a useful tool in helping with diagnosis. Imaging by second harmonic generation and multiphoton excited fluorescence microscopy were performed to evaluate the collagen and cellular segment parameters in cancer biopsies. We present a retrospective study of 45 cases of canine mammary cancer analysing 836 biopsies regions including normal mammary gland tissue, benign mixed tumours, carcinoma in mixed tumour, carcinosarcoma, micropapillary carcinoma and solid carcinoma. The image analyses and the comparison between the tumour types allowed to assess the collagen fibre changes during tumour progression. We demonstrate that the collagen parameters correlate with the clinical and pathological data, the results show that in neoplastic tissues, the collagen fibres are more aligned and shorter as compared to the normal tissues. There is a clear association of the mean fibre length with the dogs survival times, the carcinomas presenting shorter collagen fibres indicate a worse survival rate.

Canine low-grade intra-orbital myxosarcoma: case report.

OBJECTIVE: The aim of this study was to evaluate important clinical, morphological, histopathological, histochemical, and immunohistochemical characteristics in order to establish the diagnosis and prognosis of a low-grade intra-orbital myxosarcoma. ANIMAL STUDIED: A mongrel dog presented a 2-year history of a neoplastic mass behind the right eye. RESULTS: The neoplasm presented a mesenchymal spindle and stellate cell proliferation with an abundant myxoid matrix, moderate anisocariosis, and a low mitotic index. It stained positive for vimentin, moderately positive for periodic acid-Schiff, and negative for Gomori trichrome stain and α-smooth muscle actin. CONCLUSIONS: One year following surgical excision, the patient remains disease free. The histological findings established a diagnosis of a rare canine intra-orbital low-grade myxosarcoma.