F. Capela e Silva

Effect of condensed tannin ingestion in sheep and goat parotid saliva proteome

Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep (Ovis aries) and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two-dimensional gel electrophoresis. Matrix-assisted Laser desorption ionization - time of flight (MALDI-TOF) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption.

Polymeric piezoelectric actuator substrate for osteoblast mechanical stimulation

Bone mass distribution and structure are dependent on mechanical stress and adaptive response at cellular and tissue levels. Mechanical stimulation of bone induces new bone formation in vivo and increases the metabolic activity and gene expression of osteoblasts in culture. A wide variety of devices have been tested for mechanical stimulation of cells and tissues in vitro. The aim of this work was to experimentally validate the possibility to use piezoelectric materials as a mean of mechanical stimulation of bone cells, by converse piezoelectric effect. To estimate the magnitude and the distribution of strain, finite numerical models were applied and the results were complemented with the optical tests (Electronic Speckle Pattern Interferometric Process). In this work, osteoblasts were grown on the surface of a piezoelectric material, both in static and dynamic conditions at low frequencies, and total protein, cell viability and nitric oxide measurement comparisons are presented.

Morphological alterations in salivary glands of mice (Mus musculus) submitted to tannin enriched diets: comparison with sialotrophic effects of sympathetic agonists stimulation

Estudaram-se as alteracoes morfologicas das glândulas salivares, induzidas por taninos, em camundongos. Os animais foram distribuidos em grupos e tratados com tres diferentes tipos estruturais de taninos (acido tânico, chestnut e quebracho - adicionados a racao) ou isoproterenol via intraperitoneal, durante 10 dias. Os acinos das glândulas parotida e submandibulares aumentaram significativamente de tamanho, sendo o incremento maior para a parotida que para as submandibulares, e maior com o quebracho comparado com o provocado pelos outros taninos. Os acinos das glândulas sublinguais tambem aumentaram apos o consumo de taninos em relacao aos acinos dos animais tratados com isoproterenol. Os resultados apresentam evidencias de que os efeitos produzidos pelos taninos dependem de sua estrutura.

Effects of the food contaminant semicarbazide on testicular morphology of juvenile Wistar rats.

O objectivo do presente trabalho foi avaliar os efeitos da semicarbazida na morfologia testicular de ratos Wistar jovens. Os animais foram tratados durante 30 dias com hidrocloreto de semicarbazida incorporado na dieta, nas concentracoes de 0, 3 e 6g/kg. Os resultados obtidos revelaram uma diminuicao estatisticamente significativa no diâmetro dos tubulos seminiferos, no diâmetro do lumen dos tubulos seminiferos e na area ocupada pelo epitelio seminifero nos animais dos grupos experimentais em comparacao com os animais do grupo controlo. Estes resultados evidenciam que a semicarbazida induz alteracoes importantes no desenvolvimento testicular e sugerem um estudo mais aprofundado sobre os mecanismos de accao, dos efeitos a longo prazo, da reversibilidade das lesoes e nas capacidades reprodutivas. Estes aspectos sao relevantes numa perspectiva de seguranca alimentar, em particular para as criancas, as quais representam um grupo de maior exposicao e susceptibilidade a semicarbazida.

Physical characteristics of the eggs of red-legged partridge (Alectoris rufa) reared in captivity

O objetivo do presente estudo foi avaliar os efeitos da idade das femeas (um, dois e tres anos) e do mes de postura (marco, abril e maio) sobre as caracteristicas fisicas dos ovos da perdiz vermelha (Alectoris rufa) criada em cativeiro. O peso (W), o comprimento maximo (L) e a largura maxima (B) de 2878 ovos foram determinados diretamente, enquanto o indice de forma (B/L), o volume (V) e a superficie (S) foram calculados com base nos parâmetros determinados diretamente. A analise mostrou diferencas significativas (P 0,05). Observaram-se diferencas significativas (P<0,01) na largura maxima e no indice de forma do ovo entre as diferentes classes de idades, com valores mais elevados nas femeas mais velhas e no periodo de postura mais tardio. O volume dos ovos estimados por meio de V1= 0,51LB2e V2=0,913W foi afetado significativamente (P<0,01) pela idade e pelo mes de postura, bem como as areas, S1=4.835W0,662, S2=4,951V10,666e S3=4,951V20,666, as quais apresentaram os mesmos efeitos.

Effect of dithiocarbamate thiram on Wistar rat growth plate and articular cartilage

Avaliou-se o efeito do tirame, ditiocarbamato largamente utilizado na agricultura como antifungico e repelente de roedores, na ossificacao endocondral de mamiferos, usando, como modelo, ratos Wistar. Nao foram observadas lesoes na cartilagem articular, nem nas placas de crescimento, o que pode ser atribuido a dose utilizada e a duracao do ensaio. A diminuicao da altura da placa de crescimento nos animais aos quais foi administrado o tirame parece traduzir o atraso verificado no crescimento em geral, e nao um efeito especifico na cartilagem, uma vez que as diferentes zonas da placa epifisaria mantiveram as proporcoes dos animais do grupo-controle. Embora nao tenham sido verificados, no presente trabalho, os efeitos registrados para outras especies nos tecidos cartilaginosos, sugere-se a avaliacao dos efeitos cronicos do tirame no crescimento e no desenvolvimento dos ossos longos em mamiferos.

Efeitos da semicarbazida no esqueleto de ratos Wistar em crescimento

ABSTRACT The effects of semicarbazide hydrochloride on skeletal tissues were evaluated using Wistar rats. In the animals submitted to the administration of semicarbazide, radiological examination showed bone and articular alterations with growth plates enlargement. Histological exams showed irregular patterns and proliferation of chondrocytes and excessive accumulation of extracellular matrix. Immunohistochemical exams showed PCNA positive reaction in pre- and hypertrofic chondrocytes. These results confirm that semicarbazide induces important changes in skeletal tissues and that has potential utility in experimental osteolathryrism. Keywords : rat, Wistar, semicarbazide, osteolathyrism REFERENCIAS 1992, que aprova as normas tecnicas de proteccao dos FELASA. FELASA, The Federation of Laboratory Animal Science Associations, 2010. Disponivel em . Acessado em: 12 out. 2010. GARDNER, A.F.; DASLER, W.; WEINMANN, J.P. Masticatory apparatus of albino rats in experimental lathyrism.

Expressão da caderina na discondroplasia tibial

ABSTRACT By immunohistochemistry the expression of a pan-cadherin antibody that recognizes a wide variety of cadherins in chondrocytes from normal and tibial dyschondroplasia (TD) growth plates was compared. Surprisingly, an upregulated expression that was not expected in TD lesion chondrocytes was observed. The reason for this apparent upregulation is not clear. The increased expression may simply be due to the particular phenotype of lesion chondrocytes, and cadherin may be involved in apoptosis of chondrocytes of TD lesion. Another possibility, is that a low level of calcium in the lesion may be responsible for the observed upregulation. The results of the present study suggest that the formation of the dyschondroplastic lesion is not merely due to the impaired terminal differentiation of lesion chondrocytes and that other mechanisms are probably involved in TD etiology. Further studies will be necessary to provide insight into the precise nature of the condition. Keywords: tibial dyschondroplasia, cadherin, immunohistochemistry