Sinonasal Osteosarcoma in a Horse

Background: Osteosarcomas are common malignant bone tumors described in dogs, humans and cats. However, there are rare reports in horses. The tumor etiology has not been fully elucidated. Clinical signs are associated to the tumor size, location and growth characteristics. When located on the face, the most common findings are facial distortion, nasal discharge and inspiratory dyspnea. The aim of this study was to report an osteoblastic osteosarcoma in a horse, located on the right maxillary region with projections into the corresponding nostril.Case: A 6-year-old mixbreed saddle gelding, presenting bay coat was admitted to a University Hospital with a chronic sinusitis history. The animal was previously examined and treated by other veterinarians, who suspected of odontogenic maxillary sinusitis, and therefore a repulsion of the fourth premolar from the right maxilla hemiarcade was performed. However, an improvement of the clinical signs was not observed and subsequently the gelding was referred to a Veterinary Hospital. During physical examination the patient presented dyspnea, tachypnea and tachycardia. An increase on the face size was observed, together with a fetid and purulent nasal discharge. During oral cavity inspection, a diagonal wear was detected at the occlusal surface of the right hemiarcade; food accumulation was seen at the dental extraction site, and a communication with the rostral maxillary sinus was evidenced, from where a purulent fetid discharge was draining. At the radiographic exam, well defined margins of a tumor were observed, with adjacent bone lysis and the presence of a central nucleus showing a gross granular mineral radiopacity, distorting the frontal and nasal bones. During the endoscopic exam, a mass was partially occluding the right nasal cavity close to the nasal opening, which was blocking the progression of the endoscopy. However, during the left cavity inspection, at the end of the nasal septum a mass with irregular surface was detected emerging from the border of the right choana, which extended up to the nasopharynx region. The diagnosis was established based on clinical evaluation and histopathological findings of the tumor, which confirmed osteoblastic osteosarcoma. The animal was euthanized due to poor clinical conditions and prognosis. There was no evidence of metastasis to other organs during necropsy.Discussion: The majority of reported osteosarcoma cases in horses do not define the tumor histopathological subtype. The occurrence of metastasis in equine osteosarcoma is not well established, however it seems to be uncommon. It is important to emphasize the relevance of performing a necropsy in patients presenting osteosarcoma, in order to establish a pattern concerning the metastasis incidence in the species. The predominant osteosarcoma location is the mandible, although there are few reports in the paranasal sinuses and appendicular skeleton. The tumor usual location makes the treatment difficult because of the impossibility of performing a complete surgical resection, which leads to a euthanasia decision. Although osteosarcoma has been little reported in horses, it should be a differential diagnosis for facial alterations and paranasal sinuses abnormalities, which would contribute to an early diagnosis and increase the chances of a favorable prognostic

Intrasellar Chondroid Chordoma: A Case Report

Chordomas are tumors derived from cells that are remnants of the notochord, particularly from its proximal and distal extremes, they are mainly midline and represent approximately 1% of all malignant bone tumors and 0.1 to 0.2% of intracranial neoplasms. Chordomas involving the sellar region are rare. Herein, we describe a 57-year-old male patient presenting with a history of retro-orbital headache, progressive loss of vision, and clinical features of hypopituitarism, for over 2 months. During evaluation, the CT scan revealed a large contrast-enhancing intrasellar tumor with a 3.6-cm largest diameter. The patient underwent transsphenoidal partial resection of the tumor, and histological examination was consistent with the diagnosis of chondroid chordoma. Although chordomas are rare, they may be considered to constitute a differential diagnostic of pituitary adenomas, especially if a calcified intrasellar tumor with bone erosion is diagnosed

In vivo and in vitro evaluation of an Acetobacter xylinum synthesized microbial cellulose membrane intended for guided tissue repair

<p>Abstract</p> <p>Background</p> <p>Barrier materials as cellulose membranes are used for guided tissue repair. However, it is essential that the surrounding tissues accept the device. The present study histologically evaluated tissue reaction to a microbial cellulose membrane after subcutaneous implantation in mice. Furthermore, the interaction between mesenchymal stem cells and the biomaterial was studied <it>in vitro </it>to evaluate its ability to act as cellular scaffold for tissue engineering.</p> <p>Methods</p> <p>Twenty-five Swiss Albino mice were used. A 10 × 10 mm cellulose membrane obtained through biosynthesis using <it>Acetobacter xylinum </it>bacteria was implanted into the lumbar subcutaneous tissue of each mouse. The mice were euthanatized at seven, 15, 30, 60, and 90 days, and the membrane and surrounding tissues were collected and examined by histology.</p> <p>Results</p> <p>A mild inflammatory response without foreign body reaction was observed until 30 days post-surgery around the implanted membrane. Polarized microscopy revealed that the membrane remained intact at all evaluation points. Scanning electron microscopy of the cellulose membrane surface showed absence of pores. The <it>in vitro </it>evaluation of the interaction between cells and biomaterial was performed through viability staining analysis of the cells over the biomaterial, which showed that 95% of the mesenchymal stem cells aggregating to the cellulose membrane were alive and that 5% were necrotic. Scanning electron microscopy showed mesenchymal stem cells with normal morphology and attached to the cellulose membrane surface.</p> <p>Conclusion</p> <p>The microbial cellulose membrane evaluated was found to be nonresorbable, induced a mild inflammatory response and may prove useful as a scaffold for mesenchymal stem cells.</p

Amiloidase experimental no hamster (Mesocricetus auratus) induzida pelo Paracoccidioides brasiliensis : aspectos histologicos e ultraestruturais do rim; estudo da função renal, eletroferese e imunoeletroforese das proteinas sericas e urinarias

Orientador: Jose Lopes de FariaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias MedicasResumo: Inoculamos 26 hamsters (grupo 1) por via intra-testicular com 0,2ml de supensão de cultura de P. brasiliensis (cepa 18) a fim de produzir Paracoccidioidomicose experimental e com isto induzir o desenvolvimento de amiloidose nestes animais. Neste grupo, estudamos a microscopia optica e ultra-estrutural dos rins com amiloidose. Um outro grupo de animais foi inoculado de modo semelhante e em período diferente com a cepa 102 de P. brasiliensis (grupo 3), afim de se coletar destes animais urina e soro para as provas de função renal e eletroforese e imunoeletroferese de proteinas ¿Observação: O resumo, na íntegra poderá ser visualizado no texto completo da tese digital.Abstract: Not informed.DoutoradoDoutor em Ciências Médica

Composição química e qualidade biológica da torta de colza (Brassica napus, L: )

A composição química e a qualidade biológica da torta de colza obtida da semente, variedade CTC-4, foram determinados. A farinha foi preparada me diante prensagem da semente e extração da gordura com solvente, lixiviada durante 2 horas, com água corrente na proporção de 1:5, e agitação constante, a fim de reduzir os níveis de glicosinolatos. O efeito tóxico foi observado através do peso dos órgãos e da histopatologia dos órgãos em experimento de 60 dias. A qualidade biológica da torta desintoxicada, ao nível de 5% e 10%, foi semelhante ao da caseína (PER controle 3,18 vs 3,08, 5% e 2,98, 10%). O PER da torta crua foi de 2,28. Os ratos que receberam a farinha crua tiveram órgãos maiores. As tireóides dos ratos submetidos as dietas 2 e 3, não demonstraram alterações que suspeitassem de um efeito bociogênico e as alterações ocorridas nas tireóides dos animais que receberam, D-4 foram semelhantes àquelas ocorridas nos grupos 2 e 3. Não houve danos célulares graves em relação ao fígado, os rins, o coração, baço e supra-renais para todos os grupos observados. O método de extração dos fatores tóxicos da colza foi eficiente de acordo com os resultados obtidos para o presente estudo.The toxic effect of detoxified rapeseed meal obtained by 2 h lixiviation was studied in growing animals. The control diets provided 10% protein from casein, detoxified rapeseed and crude rapeseed. A fourth diet was prepared substituting half casein for detoxified rapeseed meal. Feed consumption, weight gain and protein efficiency ratio revealled good performance for all diets as compared to the crude meal. Protein efficiency ratio (PER) increased from 2,98 for detoxified rapeseed to 3,19 for casein. The lowest PER 2.16 for crude rapeseed was higher than that related by BALLESTER et alii (0,94). In animals fed crude rapeseed meal,no histological changes were detected. The detoxified material showed a satisfactory growth promoting capacity for the rats at the 10% protein dietary level. It did not cause either hypertrophy of the thyroid or histopathological damage to this gland. The present results seem to confirm the good quality of the protein of rapeseed presscake meal obtained from a low glucosinolate cultivar

Prevention of experimental venous thrombosis induced by contrast medium in the rat

In order to assess experimentally the usefulness of some procedures employed in man to prevent venous thrombosis following phlebography, thrombosis was induced in rats using sodium diatrizoate in a temporarily isolated segment of a jugular vein. The prevention of thrombosis was attempted by washing out the vein with physiologic saline or saline plus heparin or by injecting saline plus heparin in the opposite jugular vein. Thrombosis occurred in all animals in the control group and in the group treated with saline alone. Both treatment schemes with heparin significantly reduced the incidence of thrombosis, the wash out with heparin being more effective than systemic heparin

End-to-end arterial anastomosis with fibrin glue in larger arteries: histology, hydroxyproline concentration and tensile strength study in carotids of rabbits

A anastomose arterial término-terminal é demorada, requer tempo prolongado de oclusão vascular e esta associada a necrose focal, infiltração leucocitária e, conseqüentemente, à fibrose e calcificação da parede arterial. A cola de fibrina é uma alternativa para a anastomose microvascular e pode evitar estas alterações com menor aderência aos tecidos vizinhos e melhor coaptação das bordas arteriais. OBJETIVO: Comparar o processo cicatricial de anastomoses convencionais com anastomoses feitas com cola de fibrina em artérias maiores. MÉTODOS: em 22 coelhos, ambas carótidas foram seccionadas transversalmente e reconstruídas por meio de anastomose término-terminal com 4 pontos simples de reparo e cola de fibrina de um lado (G1), e com 8 pontos separados do outro lado (G2). Após 3 e 15 dias, os animais foram destinados aleatoriamente para estudo de força tênsil concentração de hidroxiprolina (8 animais) e avaliação histológica das anastomoses (3 animais). As lâminas histológicas foram coradas pelo HE Masson e Picrossirius polarização (PSP). RESULTADOS: Após 3 e 15 dias a força tênsil aumenta em ambos os grupos, de 280,0± 32,6g para 432,2± 131,2g no Grupo 1 e de 221,4± 72,4g para 452,2± 132,0g no Grupo 2; sem diferença estatística entre os grupos em cada período. A concentração de hidroxiprolina expressa como razão hidroxiprolina/proteína, variou de 0,0816± 0,0651 para 0,0622± 0,0184 no Grupo 1 e de 0,0734± 0,0577 para 0,0460± 0,0271 no Grupo 2; sem diferença estatística entre os períodos e grupos. Os estudos histológicos mostraram discreto aumento das reações de inflamação e reparação no Grupo 2. A técnica PSP mostrou predomínio do colágeno tipo I em relação do colágeno tipo II nas anastomoses de ambos os grupos, sem diferença expressiva entre esses grupos. CONCLUSÃO: A anastomose com a cola de fibrina foi menos lesiva para a parede arterial do que a anastomose convencional. Mesmo usando menos pontos, as características de força tênsil e de cicatrização da anastomose com cola de fibrina foram similares em ambos os grupos. Os tempos de realização das anastomoses foram significativamente maiores do que na anastomose convencional.End-to-end conventional arterial anastomosis is time consuming, requires prolonged clamping times and is associated with focal necrosis, granulocyte infiltration and subsequently, fibrosis and calcification of the arterial wall. Fibrin glue as an alternative for microarterial anastomosis may obviate these lesions, with less adherence to adjacent tissues and better coaptation of the arterial margins. OBJECTIVE: In this study we compared the healing process of conventional to fibrin glue end-to-end anastomosis in larger arteries. METHODS: In 22 rabbits, both carotid arteries were cross sectioned and repaired by end-to-end anastomosis with 4 interrupted sutures and fibrin glue in one side (GI) and with 8 conventional interrupted sutures in the other side (G2). After 3 and 15 days, the animals were randomly allocated for tensile strength, hydroxyproline determination (8 animals), and histologic analysis of the anastomosis (3 animals). Conventional staining procedures (hematoxylin-eosin and Masson methods) and picrosirius red polarization (PSP) technique for collagen type determination were employed. RESULTS: From 3 to 15 days, the tensile strength increased in both groups, from 280.0± 32.6 g to 432.2± 131.2g in Group I and from 221.4± 72.4g to 452.2± 132.0g in Group 2 (p0.05). Histology showed slight increase of inflammatory and reparative reactions in Group 2. PSP technique demonstrated predominant type I collagen in relation to type III collagen in the anastomosis of both groups, with no significant difference between them. CONCLUSION: Fibrin glue was less harmful to the arterial wall than conventional suture. Even using less sutures in fibrin glue anastomosis, similar tensile strength and healing characteristics were noted in both groups. Completion times for the fibrin glue group was significantly greater than for the conventional anastomosis