AVALIAÇÃO CLÍNICA, RADIOGRÁFICA E HISTOLÓGICA DA PLACA EM PONTE ASSOCIADA AO PINO INTRAMEDULAR E DA PLACA DE COMPRESSÃO DINÂMICA EM OSTEOSSÍNTESE DE FÊMUR DE COELHOS

O objetivo deste estudo foi acompanhar por avaliação clínica, radiográfica e histológica o efeito da fixação óssea com placa de compressão dinâmica (PCD) e placa em ponte (PP) associada ao pino intramedular. Foram empregados 14 coelhos da raça Nova Zelândia, quatro meses de idade, massa corporal média de 3,5 quilos. Estes foram divididos aleatoriamente em dois grupos (I e II). Todos os coelhos foram submetidos à osteotomia transversal no terço médio do fêmur direito. Nos animais do grupo I foi feita a fixação da osteotomia com PP associada ao pino intramedular, introduzidos pela técnica da mínima invasão e nos animais do grupo II utilizou-se PCD, via abordagem convencional. A técnica para colocação da PP associada ao pino intramedular permitiu alinhamento dos fragmentos e preservação das partes moles com fixação nas extremidades ósseas. Resultados positivos também foram observados nos animais submetidos a fixação da osteotomia com a PCD que propiciou fixação estável e imediata deambulação. Ao exame radiográfico, verificou-se consolidação em ambos os grupos com precocidade do processo na fixação com a PCD (grupo II). Na análise histológica aos 90 dias após a colocação dos implantes observou-se no grupo I, predomínio de tecido ósseo trabecular enquanto que no grupo II havia ausência de calo ósseo e da linha de fratura, pouca quantidade de tecido ósseo trabecular e grande quantidade de tecido ósseo osteônico com características idênticas ao tecido ósseo original. Concluiu-se que as duas modalidades de fixação conduzem à consolidação dentro do período previsto, mas a fixação com PCD promove maturação precoce do processo em relação a PP e no período avaliado, não provocou alteração da constituição óssea, revelando-se um excelente método de fixação óssea

Pneumothorax secondary to a Pulmonary Bullae in a dog

Background: Pulmonary bullae are thin-walled cavitary lesions within the subpleural parenchyma. They are a result of the destruction, dilatation and coalescence of bordering alveoli and their rupture is the most common cause of pneumothorax in dogs. Radiographic and CT imaging are excellent tools for identifying and quantifying pneumothorax. Surgical treatment is considered standard for treatment of pneumothorax consequential to pulmonary bullae. The aim of this report was to describe a case of pneumothorax secondary to pulmonary bullae in a dog.Case: A 5-year-old male crossbreed dog, weighing 11.5 kg, was presented to the Uberaba’s Veterinary Hospital due to becoming easily tired in the previous 3 weeks, and its worsening in the last 2 days by presenting panting. The dog’s guardian did not witness any traumas, but informed that the animal resided with other 14 dogs and also that it frequently collided the thorax against the door when it came down from the bed. Physical examination showed diaphragmatic breathing, inspiratory dyspnea and stridor lung sound. Thoracocentesis revealed presence of air in the pleural cavity and pneumothorax. Radiographic images confirmed this condition. The dog stayed in the hospital and chest drains were placed. Since the amount of sucked air did not reduce with time and due to the emergence of subcutaneous emphysema, the dog went through exploratory thoracotomy that revealed impairment of the right caudal lung lobe, proceeding to lobectomy. The dog stayed in the hospital with chest drains until the contents of the suctions reduced significantly. With the removal of the drains, the dog was sent home and had a full recovery. Histopathology of the impaired lung revealed pulmonary bullae.Discussion: The dog from this report presented clinical signs consistent with pneumothorax, such as dyspnea, diaphragmatic breathing and exercise intolerance. Radiography of the chest region revealed images consistent with this condition, as it is an excellent tool for identifying it. This dog’s guardian was unable to confirm if there was occurrence of trauma due to the large number of cohabitants. In dogs, spontaneous pneumothorax commonly results from the rupture of pulmonary bullae, and these bullae may result from trauma, infectious diseases, thrombosis, obstructive, neoplastic, congenital or idiopathic conditions. Except from trauma, there were no evidence to support any of the other causes of pulmonary bullae in this case.  Traumatic injuries are very common in veterinary medicine, and blunt thoracic traumas with consequential pneumothorax are especially common. The emerging of subcutaneous emphysema, as happened with this dog, is frequently associated with pneumomediastine, and rarely has pathophysiologic impairments. The patient stayed in the hospital for support therapy and thoracocentesis, corroborating with literature; but since there was no improvement, it went through exploratory lobectomy, which revealed impairment of the right caudal lung lobe, proceeding to its exeresis. Surgical intervention is standard procedure in these cases. Histopathology of the impaired lung suggested the presence of pulmonary bullae. In literature, histopathological definitions for this condition are inconsistent, but usually locate the bullae within the pulmonary parenchyma, having walls less than 1 mm thick. Through radiology, unlike with cysts, identifying pulmonary bullae is challenging. In conclusion, this report showed that pulmonary bullae should be considered as a differential diagnose in patients showing pneumothorax considering it is hard to identify through imaging, and that it is important to adopt early therapy and surgical intervention for better outcomes.Keywords: dyspnea, panting, pulmonary lobectomy, thoracotomy, chest drain.Titulo:  Pneumotórax secundário a bolha pulmonar em cão.Descritores: dispneia, ofegante, lobectomia pulmonar, toracotomia, dreno torácico

ISOLAMENTO E CULTIVO DE CÉLULAS TRONCO MESENQUIMAIS EXTRAÍDAS DO TECIDO ADIPOSO E DA MEDULA ÓSSEA DE CÃES

Objetivou-se estabelecer um protocolo para extração, cultivo e expansão de células tronco mesenquimais (CTM), utilizando-se 3,0 mL da medula óssea e 3,0 cm3 de tecido adiposo do subcutâneo de três cães machos com seis meses de idade. As amostras foram processadas e as células extraídas e cultivadas em DMEM. Para comprovação do isolamento de CTM, procedeu-se a caracterização fenotípica e a diferenciação osteogênica, adipogênica e condrogênica. As células isoladas apresentaram morfologia alongada e fusiforme e capacidade de se diferenciar em osteoblastos, adipócitos e condrócitos. A caracterização fenotípica revelou alta expressão de marcadores de CTM CD90 (80,04%) e CD29 (96%) nas células de origem medular e CD90 (60,94%) e CD29 (77,08%) nas de origem adiposa. A expressão de marcadores hematopoiéticos foi baixa tanto nas células de origem medular CD45 (1,45%) e CD34 (1,53%), quanto nas de origem adiposa CD45 (1,45%) e CD34 (1,53%). As modificações e adaptações realizadas nos protocolos clássicos simplificaram o processo e foram eficientes, permitindo o isolamento e cultivo de CTM da medula óssea e do tecido adiposo de cães.  Palavras-chaves: cultivo celular; diferenciação; medicina regenerativa

Additive Effect of rPb27 Immunization and Chemotherapy in Experimental Paracoccidioidomycosis

Paracoccidioidomycosis, PCM, the major systemic mycosis in Latin America, is caused by the termally dimorphic fungus Paracoccidioides brasiliensis and requires extended periods of chemotherapy with a significant frequency of relapsing disease. The search for new alternatives of treatment is necessary. rPb27 is an antigenic protein from P. brasiliensis that already showed a significant protective activity as a vaccine for PCM in experimental models. The cDNA of rPb27 was subcloned into a pET-DEST 42 plasmid, expressed in E. coli with a his-tag and purified by affinity chromatography. Immunization with this recombinant protein and chemotherapy were used together in an attempt to improve treatment of PCM. For this, BALB/c mice were challenged with pathogenic P. brasiliensis strain and after immunized with rPb27, in the presence of Corynebacterium parvum and Al(OH)3, some groups were also treated with fluconazole. After 40 days of treatment, the combined drug/rPb27 administration controlled PCM in the liver and spleen, with long lasting protection, and largely preserved tissues structures of these organs. Additionally, in the lungs after 40 days of treatment there was a significant reduction in the fungal load and size of lesions. At the same time, the levels of TNF-α were higher than infected-only mice. Moreover, significant levels of anti-rPb27 specific IgG1, IgG2a and IgG2b isotypes were detected in the sera of mice immunized with rPb27 fluconazole treated or not. These results showed an additive protective effect of rPb27 immunization and chemotherapy, suggesting that an rPb27-based vaccine can be used to enhance PCM antifungal treatment

Immunophenotypic features of tumor infiltrating lymphocytes from mammary carcinomas in female dogs associated with prognostic factors and survival rates

<p>Abstract</p> <p>Background</p> <p>The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas.</p> <p>Methods</p> <p>Fifty-one animals with mammary carcinomas, classified as carcinomas in mixed tumors-MC-BMT = 31 and carcinomas-MC = 20 were submitted to systematic clinical-pathological analysis (tumor size; presence of lymph node and pulmonary metastasis; clinical stage; histological grade; inflammatory distribution and intensity as well as the lymphocytic infiltrate intensity) and survival rates. Twenty-four animals (MC-BMT = 16 and MC = 8) were elected to the immunophenotypic study performed by flow cytometry.</p> <p>Results</p> <p>Data analysis demonstrated that clinical stage II-IV and histological grade was I more frequent in MC-BMT as compared to MC. Univariate analysis demonstrated that the intensity of inflammation (moderate/intense) and the proportion of CD4⁺(≥ 66.7%) or CD8⁺T-cells (<33.3%) were not associated with worse survival rate. Multivariate analysis demonstrated that only lymphocytic infiltrate intensity ≥ 600 (<it>P </it>= 0.02) remained as independent prognostic factor. Despite the clinical manifestation, the lymphocytes represented the predominant cell type in the tumor infiltrate. The percentage of T-cells was higher in animals with MC-BMT without metastasis, while the percentage of B-lymphocytes was greater in animals with metastasized MC-BMT (<it>P </it>< 0.05). The relative percentage of CD4⁺T-cells was significantly greater in metastasized tumors (both MC-BMT and MC), (<it>P </it>< 0.05) while the proportion of CD8⁺T-cells was higher in MC-BMT without metastasis. Consequently, the CD4⁺/CD8⁺ratio was significantly increased in both groups with metastasis. Regardless of the tumor type, the animals with high proportions of CD4⁺and low CD8⁺T-cells had decreased survival rates.</p> <p>Conclusion</p> <p>The intensity of lymphocytic infiltrate and probably the relative abundance of the CD4⁺and CD8⁺T-lymphocytes may represent important survival prognostic biomarkers for canine mammary carcinomas.</p