Biocompatibility, induction of mineralization and antimicrobial activity of experimental intracanal pastes based on glass and glass-ceramic materials.

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 .

Fluorodeoxyglucose positron emission tomography in pulmonary carcinoid tumors.

AIM: The role of fluorodeoxyglucose positron emission tomography (FDG-PET) as an additional investigation to computer tomography for pulmonary carcinoid tumors remains controversial. The aim of this study was to assess the role of FDG-PET for the diagnosis and staging of pulmonary carcinoid tumors. METHODS: We performed a retrospective mono-institutional analysis of data from 97 patients with pathologically confirmed pulmonary carcinoid tumor who had been operated on between July 1998 and April 2009 and had had a preoperative FDG-PET scan performed. RESULTS: Sixty-five (67%) of the 97 tumors were typical (TC) and 32 (33%) atypical (AC) carcinoid tumors. Overall FDG-PET sensitivity was 67% being lower for TC (60%) than for AC (81%) (P=0.04). FDG-PET negative tumors were smaller than FDG-PET positive tumors, with a respective median size of 15 and 17 mm (P=0.02). Median SUVmax for FDG-PET-positive tumors was 4.0 (2.8-5.1) with no difference between TC and AC tumors. Median Ki-67 expression was respectively 4.7% and 3.1% for FDG-PET positive and FDG-PET negative tumors (P=0.05). During a median follow-up of 49 months (interquartile range 30-63 months), 9 patients (4TC, 5AC) developed recurrent disease. Neither SUVmax nor Ki-67 expression resulted associated with disease-free survival. CONCLUSION: With an overall sensitivity of 67%, FDG-PET has shown to be useful in the preoperative work-up of patients with suspect lung carcinoid tumors. In particular it could have a role in larger tumors. These results warrant a prospective evaluation of FDG-PET in the staging of lung carcinoid tumor.

Ecological aspects of helminth fauna of Magellanic penguins, Spheniscus magellanicus (aves: Spheniscidae), from the Northern Coast of the State of São Paulo, Brazil.

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.