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AIM: To evaluate the biocompatibility, induction of mineralization and antimicrobial activity of experimental intracanal pastes based on two glass and glass-ceramic materials. Calcium hydroxide (Ca(OH)2 ) paste was used as the positive control. METHODOLOGY: The glass-ceramic powder [two-phased Biosilicate (BS-2P)] and F18 bioactive glass were mixed with distilled water (ratio 2 : 1), inserted in polyethylene tubes and implanted in the subcutaneous tissues of 16 rats. Empty tubes were used as negative control. After 7 and 30 days (n = 8), the rats were euthanized for haematoxylin-eosin, von Kossa, polarized light and osteopontin (OPN) immunolabeling analysis. Direct contact tests using a suspension of each paste were performed with Enterococcus faecalis planktonic cells to evaluate antimicrobial activity (24 h of contact), in a pilot study. The number of CFU mL-1 was calculated for each group. The antimicrobial analysis data were submitted to one-way anova and Tukey tests, whilst biocompatibility and immunohistochemical data were submitted to the Kruskal-Wallis and Dunn tests (P < 0.05). RESULTS: Most specimens of the control, BS-2P and Ca(OH)2 groups were associated with moderate inflammation seven days following implantation, whilst F18 was associated with moderate to severe inflammation, without differences amongst the groups (P > 0.05). At 30 days, most specimens of control, F18 and BS-2P groups had mild inflammation, whilst Ca(OH)2 had mild to moderate inflammation; however, no differences were determined amongst the groups (P > 0.05). The fibrous capsule was thick at 7 days, becoming thin at 30 days. All pastes induced von Kossa-positive structures and were birefringent to polarized light. At seven days, the BS-2P group had significantly more OPN immunolabeling compared to the control and Ca(OH)2 groups (P < 0.05). At 30 days, the F18 group had significantly more OPN immunolabeling compared to the control and Ca(OH)2 groups (P < 0.05). All pastes reduced the total number of E. faecalis; however, the reduction was only significant when comparing BS-2P and Ca(OH)2 groups to the control (P < 0.05). Only calcium hydroxide eliminated E. faecalis. CONCLUSIONS: Experimental BS-2P and F18 pastes were biocompatible, stimulated biomineralization and induced significant OPN immunolabeling compared to Ca(OH)2 . Only the BS-2P paste demonstrated antimicrobial activity comparable to Ca(OH)2 .

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RESUMO

The aim of the present study was to evaluate the helminth fauna found in the Magellanic penguin, Spheniscus magellanicus, relating parasite population and community ecological parameters to life aspects of the host species. The study involved 237 specimens of S. magellanicus taken from the northern shore of the state of São Paulo (23° 46' S, 45° 57' W) and southern shore of the state of Rio de Janeiro (23° 02' S, 44° 13' W), Brazil. The following helminth fauna were found: the nematode Contracaecum pelagicum (core species), found in the stomach; the digenetic Cardiocephaloides physalis and the cestode Tetrabothrius lutzi (satellite species), both collected from the initial portion of the small intestine. Comparisons using the Shannon Diversity Index revealed that the parasite community in juvenile penguins is less diverse in the migratory season than the breeding season. Parasitological studies on penguins and other migratory animals provide important information on species during the time in which they remain pelagic and constitute a useful tool for the acquisition of data that is difficult to obtain through other means, thereby favoring the conservation of the species.

Assuntos

RESUMO

The aim of the present study was to evaluate the helminth fauna found in the Magellanic penguin, Spheniscus magellanicus, relating parasite population and community ecological parameters to life aspects of the host species. The study involved 237 specimens of S. magellanicus taken from the northern shore of the state of São Paulo (23° 46' S, 45° 57' W) and southern shore of the state of Rio de Janeiro (23° 02' S, 44° 13' W), Brazil. The following helminth fauna were found: the nematode Contracaecum pelagicum (core species), found in the stomach; the digenetic Cardiocephaloides physalis and the cestode Tetrabothrius lutzi (satellite species), both collected from the initial portion of the small intestine. Comparisons using the Shannon Diversity Index revealed that the parasite community in juvenile penguins is less diverse in the migratory season than the breeding season. Parasitological studies on penguins and other migratory animals provide important information on species during the time in which they remain pelagic and constitute a useful tool for the acquisition of data that is difficult to obtain through other means, thereby favoring the conservation of the species.(AU)

Com o intuito de investigar se estudos parasitológicos podem ser utilizados como ferramenta para a conservação de espécies, principalmente migratórias, este trabalho analisa a helmintofauna de Spheniscus magellanicus por meio de parâmetros ecológicos populacionais e da comunidade parasitária, relacionando-os com diversos aspectos de vida da espécie hospedeira. O estudo foi realizado com 237 espécimes de S. magellanicus procedentes das praias do litoral norte de São Paulo (23° 46' S, 45° 57' W) ao sul do Rio de Janeiro (23° 02' S, 44° 13' W). A helmintofauna desta ave incluiu: o nematoide Contracaecum pelagicum (espécie-núcleo), encontrado no estômago; o digenético Cardiocephaloides physalis e o cestoide Tetrabothrius lutzi (espécies satélites), ambos coletados na porção inicial do intestino delgado. Comparações utilizando o índice de diversidade de Shannon mostraram que a comunidade de parasitas em filhotes durante o período migratório é menos diversa do que na estação reprodutiva. Os resultados obtidos permitem inferir que estudos parasitológicos em pinguins, assim como em outros animais migratórios, podem fornecer informações importantes a respeito da espécie durante a época em que permanece pelágica, tornando-se uma ferramenta útil na aquisição de informações dificilmente obtidas por outros meios e favorecendo, dessa forma, a conservação da espécie.(AU)

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