Browsing by Author "Esteves, F"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Histopathological evaluation of sheep from deactivated uranium minesPublication . Esteves, F; Carvalho, F.P.; Oliveira, J.M.; Malta, M.; Melo, M.E.; Vala, HelenaBackground: Until the beginning of the XXI century, 60 mines of uranium and radium (226Ra) have been explored in Portugal, producing waste contaminated with radioactive elements, sometimes in very high concentrations, abandoned in the debris deposited on the surface. The program to assess the environmental impact of waste, from old uranium mines, detected the existence of public health and environmental risks. Previous studies validated vertebrate species, as indicators of genotoxicity and exposure to metals, in mining areas. Objectives: The aim of this work was the detection of radioactive elements in specimens of autochthonous breed of Serra da Estrela sheep, grazing in areas with high environmental radioactivity and respective pathological study, with a view to predicting exposure and effects in humans. Methods: Necropsy of 3 adult specimens, from a flock in an area where there was uranium mining - Arcozelo da Serra (Gouveia municipality) was performed. The study of accumulation of radionuclides of uranium and its radioactive progeny was performed by radiochemical, followed by alpha spectrometry. Simultaneously, samples of several organs were fixed in 10% neutral-buffered formalin, for a maximum of 48 hours, embedded in paraffin wax, and 3µm sections were stained for routine histopathological diagnosis. Results: In the sheep studied, the presence of radionuclides in the uranium series, all in the internal organs, was registered and the liver and kidneys displayed the highest concentrations. The lesions observed were compatible with high parasitic infestation of several systems and lesions compatible with multisystemic process, most notorious interstitial pneumonia, apparently from viral aetiology - ovine pulmonary adenocarcinoma and chronic granulomatous enteritis and lymphadenitis - paratuberculosis. Conclusion: It was concluded that the levels of uranium remains high in areas of deactivated uranium mines, being present in the food chain, including in the tissues and internal organs of sheep raised in proximity but at lower concentrations than those reported to produce biological effects animals and their consumers. Histopathological diagnosis revealed the presence of infectious diseases which are common throughout the region, hypothesizing that these animals could have been more susceptible, given the increase expression and severity of the conditions presented.
- Presence of Kimmelstiel-Wilson like lesions in canine renal faillurePublication . Vala, Helena; Mega, A. C.; Mesquita, J.; Nóbrega, C.; Cruz, R.; Esteves, F; Santos, C.; Teixeira de Lemos, E.; Reis, F.Background: Nodular increases in mesangial matrix is the definition of Kimmelstiel-Wilson (K-W) lesions. In man, focal mesangiolyses and K-W nodules were positively associated with diabetes, proteinuria and hyalinization of afferent and efferent arterioles. Although, nodular sclerotic lesions may also occur in the absence of diabetic nephropathy and are clinically related to hypertension, smoking, hypercholesterolemia, among others. This study aimed to assess the presence of nodular glomerulosclerosis in dogs in non-diabetic chronic kidney disease. Materials and Methods A retrospective study including dogs with non-diabetic chronic kidney disease (n=27) was performed. Samples were stained with haematoxylin-eosin and periodic acid of Schiff and classified according to Maxie (2007). Lesions were classified as absent or present and the later, as non-convincing and convincing K-W like lesions. Univariate logistic regression models were performed to measure the association between a positive histological diagnosis of K-W lesions and the accessed histological features (variables membranes, inflammation, atrophy and fibrosis) by using statistical software R with Epicalc package. Results Nodular glomerulosclerosis was present in 66.66% of evaluated cases (n=18) of which, 38.88% (n=7) were classified as convincing and 61.11% (n=11) as non-convincing. The convincing K-W like lesions observed, revealed similar microscopic aspects to the descriptions in literature related to man. The presence of fibrosis was positively associated to the diagnosis of K-W lesions (OR=6; p<0.05). The remaining variables were not statistically associated (p>0.05). Conclusion Presence of K-W like lesions, in dogs with renal failure exposed a possible association with end-stage renal disease. Therefore, the diagnosis of K-W like lesions could be helpful to specify and define renal biopsies.