Stereological analysis of metanephros from domestic cat (Felis catus, Linnaeus 1798) embryos and fetus.

Kidney diseases are the most common illness for cats with a prevalence seven times higher than in dogs. Metanephros is the last of three renal systems to be formed during the embryonic period, which then becomes the permanent kidney. The current work aimed to analyse the morphology and to quantify the structures present in the development of metanephros from domestic cat (Felis catus) embryos and foetuses. For this purpose, the evaluation of the biometric parameters of metanephros from cat embryos and foetuses was performed in addition to the quantification of renal corpuscles and volume of cortical and medullary layers by stereological analysis. The evaluated biometric parameters were weight, width, height, thickness and volume. The values of the measured biometric parameters increased throughout the gestational stages. The quantity of renal corpuscles gradually increased following the embryo-foetal development, mainly during the middle of the gestational stage. It was during this phase that morphologically, a complete corticomedullary division was observed. Although the difference in the quantity of renal corpuscles between the middle and the end of the gestational stages was not statistically significant, there was an increase in the volume of the medullary layer and a decrease in the volume of the cortical layer between these two stages. These findings suggest that the metanephros presents a progressive growth with the renal corpuscles following this development until the middle of the gestational stage. Starting from this phase, the differentiation of the corticomedullary layers can be seen with a significant increase in the medullary layer.

Combination therapy of canine osteosarcoma with canine bone marrow stem cells, bone morphogenetic protein and carboplatin in an in vivo model

Osteosarcoma (OSA) is the most common malignant bone cancer in children and dogs. The ther-apeutic protocols adopted for dogs and humans are very similar, involving surgical options suchas amputation. Besides surgical options, radiotherapy and chemotherapy also are adopted. How-ever, hematologic, gastrointestinal and renal toxicity may occur because of chemotherapy treat-ments. Recent study clearly showed that mesenchymal stem cells (MSCs) combined withrecombinant human bone morphogenetic protein (rhBMP-2) may be associated with decreasesof the tumorigenic potential of canine OSA. The aim of this study was to analyse the efficacy ofchemotherapy with carboplatin and rhBMP-2 with MSCs in a canine OSA in vivo model. CanineOSA cells were implanted in mice Balb-c/nude with MSCs, rhBMP-2 and carboplatin. Flow cyto-metry and PCR for markers involved in tumour suppression pathways were analysed. Resultsshowed that the combination of MSCs and rhBMP-2 reduced tumour mass and infiltration ofneoplastic cells in tissues more efficiently than carboplatin alone. Thus it was demonstrated thatthe use of rhBMP-2 and MSCs, in combination with conventional antineoplastic, may be an effi-cient treatment strategy.

Combination therapy of canine osteosarcoma with canine bone marrow stem cells, bone morphogenetic protein and carboplatin in an in vivo model

Osteosarcoma (OSA) is the most common malignant bone cancer in children and dogs. The ther-apeutic protocols adopted for dogs and humans are very similar, involving surgical options suchas amputation. Besides surgical options, radiotherapy and chemotherapy also are adopted. How-ever, hematologic, gastrointestinal and renal toxicity may occur because of chemotherapy treat-ments. Recent study clearly showed that mesenchymal stem cells (MSCs) combined withrecombinant human bone morphogenetic protein (rhBMP-2) may be associated with decreasesof the tumorigenic potential of canine OSA. The aim of this study was to analyse the efficacy ofchemotherapy with carboplatin and rhBMP-2 with MSCs in a canine OSA in vivo model. CanineOSA cells were implanted in mice Balb-c/nude with MSCs, rhBMP-2 and carboplatin. Flow cyto-metry and PCR for markers involved in tumour suppression pathways were analysed. Resultsshowed that the combination of MSCs and rhBMP-2 reduced tumour mass and infiltration ofneoplastic cells in tissues more efficiently than carboplatin alone. Thus it was demonstrated thatthe use of rhBMP-2 and MSCs, in combination with conventional antineoplastic, may be an effi-cient treatment strategy.

Progesterone Decreases in vitro Indoleamine 2, 3-dioxygenase Expression in Dendritic and CD4+ Cells from Maternal-Fetal Interface of Rats.

PROBLEM: Several mechanisms contribute to the tolerogenic state observed during pregnancy, such as the activity of the enzyme indoleamine 2, 3-dioxygenase (IDO). This initializes the catabolism of tryptophan, inducing T cells to apoptosis due to its deprivation and by the action of its catabolites in the placental microenvironment. Progesterone plays an important part on immunological tolerance mechanisms during pregnancy; however, there is no evidence it is related to IDO activity. Thus, this study aimed to investigate progesterone influence on the maternal-fetal interface of pregnant Wistar rats, by identifying IDO positive cells by immunophenotyping and flow cytometry under exogenous progesterone supplementation. METHOD OF STUDY: Placenta and embryo cells were cultured and separated into groups that received interferon γ or progesterone, supplemented or not with mifepristone. After 2 and 24 h, these were labeled with an anti-IDO and a series of antibodies specific to leucocytes and progesterone receptor and processed through flow cytometry analysis. RESULTS: Progesterone induced a significant decrease in the expression of IDO in dendritic cells and CD4+ lymphocytes. CONCLUSION: The blocking of progesterone receptor on these cells by mifepristone restored IDO expression levels and may constitute evidence of the participation of this hormone through a direct route in these cells.

The importance of clinical, histopathological and immunohistochemical marking for differential diagnosis of non-hematopoietic gastrointestinal mesenchymal neoplasms in dogs: literature review / Importância da avaliação clínica, anatomopatológica e imuno-histoquímica para o diagnóstico diferencial das neoplasias mesenquimais gastrointestinais não hematopoiéticas em cães: revisão de literatura

Gastrointestinal neoplasms in dogs represent a challenge for the veterinary clinician and surgeon as they are mostly malignant and when the owner notices the primary clinical changes the disease may already be in an advanced stage. Due to the high clinical and histopathological similarity between mesenchymal gastrointestinal neoplasms, it is often impossible to establish the definitive morphological diagnosis using light microscopy alone. In addition, there are only a few articles describing the anatomopathological and immunohistochemical characteristics, which make its complete characterization urgent and relevant in our context in order to assist the veterinary clinician, surgeon, and pathologist in establishing a precise diagnosis of these tumors.(AU)

As neoplasias gastrointestinais em cães representam casos desafiantes ao clínico e cirurgião, pois são em sua maioria malignas e, quando as primeiras alterações clínicas são notadas pelo proprietário do animal, a doença pode estar em estágio de desenvolvimento muito avançado. Devido à elevada similaridade clínica e histopatológica entre as neoplasias gastrointestinais mesenquimais, muitas vezes não é possível estabelecer o diagnóstico morfológico definitivo apenas com a microscopia de luz. Acrescenta-se que são poucos os artigos que descrevem as características anatomopatológicas e imuno-histoquímicas das neoplasias mesenquimais gastrointestinais que acometem os cães, o que torna premente a caracterização destas em nosso contexto, com o intuito de auxiliar clínico, cirurgião e patologista veterinário a estabelecer o diagnóstico destes tumores.(AU)

Morphology of the adrenal glands of giant anteater (Myrmecophaga tridactyla, Linnaeus, 1758) of wild life / Morfologia das glândulas adrenais de tamanduá-bandeira (Myrmecophaga tridactyla, Linnaeus, 1758) de vida livre

The Myrmecophaga tridactyla (family Pilosa), popularly known in Brazil as the giant anteater is classified as an endangered species by the main survey agencies of biodiversity preservation around the world. The adrenal glands are important organs, which are related to homeostasis of the animal. This study aimed to describe the morphology of the adrenal glands of M. tridactyla, providing data for future studies related to the production of steroid hormones in specimens exposed to different stress factors. The adrenal glands of 14 specimens were used. The glands were measured, photodocumented and described by light microscopy. The adrenals were positioned in the cranial extremity of the kidneys (left and right) and related medially to the caudal vena cava. The right adrenal gland had an elongated shape while the left adrenal gland had pyramidal or triangular shape. The weight was 4.765±0.129g for the right adrenal and 3.975±0.213g for the left adrenal. The length was 4.50±0.14cm for the right adrenal and 4.28±0.11cm for the left adrenal. The width was 2.60±0.13cm for the right adrenal and 2.37±0.12cm for the left adrenal. The thickness was 0.45±0.11cm for the right adrenal and 0.68±0.14cm for the left adrenal. Statistical differences (p<0.05) between right and left adrenals for all values analyzed were observed. Microscopically it was observed a capsule composed by modeled dense connective tissue lining the organ. Below this capsule, from the outermost to the innermost layer, it was observed a cortical region divided into glomerular, fasciculata and reticular zones with a medullar region occupying the center of the organ. Further studies related to steroidogenesis with specimens collected at different periods of the year are necessary, aiming to observe if there are morphological or hormonal variations in the adrenal glands due to seasonal periods. This information would be of great importance because it could reflect the behavioral habits of this species.

O Myrmecophaga tridactyla (família Pilosa), conhecido popularmente no Brasil como Tamanduá- Bandeira, é uma espécie classificada como ameaçada de extinção pelos principais órgãos de levantamento e preservação da biodiversidade no mundo. As glândulas adrenais são importantes órgãos, relacionados com a homeostasia dos animais. Neste estudo, objetivou-se descrever a morfologia das glândulas adrenais de M. tridactyla, fornecendo dados para futuros estudos relacionados à produção de hormônios esteroides em espécimes expostos a diferentes fatores de stress. Esta pesquisa traz a análise das glândulas adrenais em 14 espécimes de M. tridactyla, as quais foram mensuradas, fotodocumentadas, processadas e analisadas por microscopia de luz. Encontrou-se que as glândulas adrenais pares estavam posicionadas na extremidade cranial dos rins e relacionadas medialmente com a veia cava caudal. Sendo que, a glândula adrenal direita possuía formato mais alongado que a glândula adrenal esquerda, a qual apresentou formato piramidal ou triangular. A massa da glândula adrenal direita foi de 4,765±0,129g, enquanto a esquerda pesou 3,975±0,213g. O comprimento foi de 4,50±0,14cm para a glândula direita e 4,28±0,11cm para a esquerda. A largura foi de 2,60±0,13cm para a glândula direita e 2,37±0,12cm para a esquerda. A espessura da glândula direita foi de 0,45±0,11cm e da esquerda foi 0,68±0,14. Foram observadas diferenças estatísticas (p<0,05) entre as glândulas direitas e esquerdas em todas as dimensões analisadas. Com auxílio de microscopia de luz observou-se uma cápsula de tecido conjuntivo denso modelado, revestindo o órgão. Abaixo dessa cápsula, foi possível evidenciar, da camada mais externa para a mais interna, uma região cortical, dividida em zonas glomerular, fasciculada e reticular, com uma região medular ocupando o centro do órgão. Futuros estudos relacionados à esteroidogênese adrenal com espécimes em diferentes épocas do ano poderiam demonstrar se as glândulas adrenais apresentam variações sazonais em sua conformação morfológica ou na produção de hormônios adrenais decorrentes dessas variações, sendo que, estes dados seriam de grande importância, pois poderiam refletir os hábitos comportamentais nesta espécie.

Is the canine corpus luteum an insulin-sensitive tissue?

This study aimed to determine in the canine corpus luteum throughout the dioestrus (1) the influence of insulin on glucose uptake; (2) the regulation of genes potentially involved; and (3) the influence of hypoxia on glucose transporter expression and steroidogenesis, after treatment with cobalt chloride (CoCl2). Glucose uptake by luteal cells increased 2.7 folds (P < 0.05) in response to insulin; a phenomenon related to increased expression of glucose transporter (GLUT) 4 and phosphorylation of protein kinase B (AKT). The gene expression of insulin receptor and SLC2A4 (codifier of GLUT4) genes after insulin stimulation increased on day 20 post ovulation (p.o.) and declined on day 40 p.o. (P < 0.05). Regarding potentially involved molecular mechanisms, the nuclear factor kappa B gene RELA was upregulated on days 30/40 p.o., when SLC2A4 mRNA was low, and the interleukin 6 (IL6) gene was upregulated in the first half of dioestrus, when SLC2A4 mRNA was high. CoCl2 in luteal cell cultures increased the hypoxia-inducible factor HIF1A/HIF1A and the SLC2A4/GLUT4 expression, and decreased progesterone (P4) production and hydroxyl-delta-5-steroid dehydrogenase 3 beta (HSD3B) mRNA expression (P < 0.05). This study shows that the canine luteal cells are responsive to insulin, which stimulates glucose uptake in AKT/GLUT4-mediated pathway; that may be related to local activity of RELA and IL6. Besides, the study reveals that luteal cells under hypoxia activate HIF1A-modulating luteal function and insulin-stimulated glucose uptake. These data indicate that insulin regulates luteal cells' glucose disposal, participating in the maintenance and functionality of the corpus luteum.

Environmental risk factors related to the development of canine non-Hodgkin's lymphoma / Fatores de risco ambientais relacionados ao desenvolvimento do linfoma não Hodgkin canino

This research aimed to investigate the possible risk factors associated with the development of canine non-Hodgkin's lymphoma. Owners of 83 dogs with non-Hodgkin's lymphoma and of 84 healthy dogs answered an epidemiological questionnaire. Dogs who lived outside of the house and within 100 meters of busy streets or avenues (defined as more than 50 vehicles per minute) had a higher risk for developing the disease (OR: 3.1, 95% CI: 1.4-6.9, P=0.005). These results suggest that air pollution derived from vehicle traffic may be associated with the development of canine non-Hodgkin's lymphoma.

Este trabalho teve como objetivo investigar os possíveis fatores de risco ambientais, associados com o desenvolvimento de linfoma não-Hodgkin nos cães. Um questionário epidemiológico foi aplicado aos proprietários de 83 cães com linfoma não-Hodgkin e 84 proprietários de cães saudáveis. Os cães que viviam permanentemente no lado de fora da casa e em torno de 100 metros de ruas movimentadas ou avenidas (mais de 50 veículos por minuto) tiveram um maior risco de desenvolvimento da doença (OR: 3,1, IC 95%: 1,4-6,9, P=0,005). Esses resultados sugerem que a poluição do ar oriunda do tráfego veicular pode estar associada com o desenvolvimento de linfomas não-Hodgkin canino.