The effectiveness of seven disinfectant compounds used in dentistry for a rapid decontamination of 32 guttapercha cones adhered with Staphylococcus aureus, Enterococcus faecalis, Escherichia coli strains or Bacillus subtilis spores was compared. Cones were treated with 2% glutaraldehyde, 1% sodium hypochlorite, 70% ethyl alcohol, 1% and 0.3% iodine alcohol, 2% chlorhexidine, 6% hydrogen peroxide, and 10% polyvinylpyrrolidone-iodine, for 1, 5, 10, and 15 minutes. After treatment, each cone was transferred to thioglycollate broth and incubated at 37ºC for 7 days. The products were bactericidal after 1 to 5 minutes and, with exception of ethyl alcohol and iodine-alcohol, sporicidal after 1 to 15 minutes of exposure. Results suggest that chlorhexidine, sodium hypochlorite, polyvinylpyrrolidone-iodine, hydrogen peroxide, and glutaraldehyde were the most effective products in the decontamination of gutta-percha cones.

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ABSTRACT. This experiment measured total bacterial numbers in the gastrointestinal regions of semi-intensively cultured tilapia, Oreochromis niloticus L. (Cichlidae). Mean bacterial numbers were higher in both anterior and posterior gut than in stomach. The percentage of isolated species and the percentage of isolates from any particular species varied significantly among gastrointestinal tract regions. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans and Plesiomonas shigelloides were the most frequently isolated Gramnegative bacilli. From these samples, only Plesiomonas shigelloides was present in both gastrointestinal regions, with higher number in the posterior gut (76%), when compared to anterior gut (4.8%) and stomach (0.6%). Aeromonas hydrophila (0.6%), Escherichia coli (7.4%), and Flavimonas oryzihabitans were isolated only in the stomach, and Citrobacter freundii and Burkholderia cepacia were found only in the posterior gut. Chromobacterium violaceum was the dominant bacteria isolated from stomach and anterior gut, with 90% and 55%, respectively. Unidentified organisms comprised 0 -39.3% of the gastrointestinal microflora.Key words: tilapia, bacterial flora, gastrointestinal tract, Oreochromis niloticus RESUMO. Flora bacteriana de tilápia do Nilo, Oreochromis niloticus, cultivada em sistema semi-intensivo. A flora bacteriana de diferentes partes do trato gastrintestinal de tilápia Oreochomis niloticus L. (Cichlidae) foi determinada. O número médio de bactérias foi maior no intestino anterior e posterior quando comparado ao estômago. A porcentagem total de espécies bacterianas isoladas e a porcentagem de espécies isoladas em uma espécie particular variaram significativamente entre as regiões do trato gastrintestinal. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans e Plesiomonas shigelloides foram os bacilos Gram-negativos encontrados com maior freqüência. Destas espécies, somente Plesiomonas shigelloides esteve presente em cada região do trato gastrintestinal, apresentando maior número no intestino posterior (76%), quando comparado com o intestino anterior (4.8%) e o estômago (0.6%). Aeromonas hydrophila (0.6%), Escherichia coli (7.4%), e Flavimonas oryzihabitans foram isoladas somente do estômago, e Citrobacter freundii e Burkholderia cepacia foram encontradas somente no intestino posterior. Chromobacterium violaceum foi a espécie dominante isolada do estômago e do intestino anterior com 90% e 55%, respectivamente. Organismos não identificados compreendem 0 -39.3% da microbiota gastrintestinal.

In Brazil and several other Latin American countries, Chagas' disease still constitutes a serious medical and social problem, and there is a need to develop new, more-potent drugs with fewer side effects to effectively treat this disease. We investigated the antitrypanosomal effect of a crude extract, fractions, and a semi-purified subfraction rich in a mix- ture of isomeric labdane sesquiterpenes, obtained from flowers of Anthemis tinctoria, against Trypanosoma cruzi. In epimastigote forms, the aqueous crude extract, dichloromethane fraction, and semi-purified subfraction showed a dose-dependent inhibitory activity, with IC50 of 2.3 μg/ml, 1.8 μg/ml, and 0.2 μg/ml, respectively. In the interaction in- dex, the semi-purified subfraction showed a reduction in both the percentage of infected LLCMK2 cells and the mean number of amastigotes per infected cell. The cytotoxicity evaluation demonstrated that the cytotoxic concentrations of the semi-purified subfraction were higher for LLCMK2 cells than for the protozoans, with a selectivity index of 35.0. Epimastigote forms treated with the semi-purified subfraction showed ultrastructural and morphological alterations such as rounding of the cells and bleb formation in the flagellum and cytoplasmic membrane. These results show that the flowers from A. tinctoria may be a source of new drugs with antiprotozoal activity. However, additional in vitro and in vivo studies are needed to validate the use of A. tinctoria in the treatment of Chagas’ disease

ABSTRACT. The aim of the present study was to investigate the reference ranges for haematological and biochemical values for Nile tilapia, Oreochromis niloticus (Cichlidae), cultivated in a semi-intensive system. Erythrocytes number was 6.93 ± 8.28 x 10 6 /mm 3 , hemoglobin 10.52 ± 3.09g/dL of blood and hematocrit 31.85 ± 8.45%, mean corpuscular volume (MVC) 148.80 ±. 153.19µ 3 , mean corpuscular hemoglobin (MCH) 40.74 ± 34.19 pg and mean corpuscular hemoglobin concentration (MCHC) 35.24 ± 14.92%. Total plasma protein and glucose values obtained were 3.06 ± 0.65g/dl and 60.32 ± 20.22mg/dl, respectively. A correlation matrix was established to compare de degree of association among biometric data and hematological parameters, and among each of them and biochemical values. A positive correlation was observed among weight, length, MCV and MHC, as well as between length and hematocrit. The blood glucose level was positively correlated with weight and length, whereas total protein was positively correlated with hemoglobin. The erythrocytes count was positively correlated with hemoglobin and negatively correlated with MCV and MHC. Microscopy examination of blood smears revealed the presence of erythrocytes, neutrophils, lymphocytes, and monocytes. Under the conditions employed here, no basophils or eosinophils, nor their precursors, could be found in blood smears of Nile tilapia.Key words: Nile tilapia, Oreochromis niloticus, haematology, biochemistry. RESUMO. Valores hematológicos e bioquímicos em tilápia do NiloOreochromis niloticus cultivada em sistema semi-intensivo. O objetivo do presente estudo foi investigar os valores de referências hematológicos e bioquímicos para a tilápia do Nilo, Oreochromis niloticus (Cichlidae), cultivada em sistema semi-intensivo. A contagem de eritrócitos foi 6,93 ± 8,28 x 10 6 /mm 3 , hemoglobina 10,52 ± 3,09g/dL de sangue, hematócrito 31,85 ± 8,45%, volume corpuscular médio (MVC) 148,80 ±.153,19µ 3 , hemoglobina corpuscular média (MCH) 40,74 ± 34,19pg e concentração de hemoglobina corpuscular média 35,24 ± 14,92%. Os valores de proteína plasmática total e da glicose obtidos foram de 3,06 ± 0,65g/dl e 60,32 ± 20,22mg/dl, respectivamente. Uma matriz de correlação foi estabelecida para comparar o grau de associação entre os dados biométricos e parâmetros hematológicos, e entre estes e os valores bioquímicos. Uma correlação positiva foi observada entre peso, comprimento, MCV e MHC, bem como entre comprimento e hematócrito. O nível de glicose sanguínea foi positivamente correlacionado com o peso e o comprimento, enquanto proteína total foi positivamente correlacionada com a hemoglobina. A contagem de eritrócito foi positivamente correlacionada com a hemoglobina e negativamente correlacionada com MCH e MHC. A observação microscópica do esfregaço sangüíneo revelou a presença de eritrócitos, neutrófilos, linfócitos e monócitos. Sob as condições empregadas no estudo não foram encontrados basófilos, ensinófilos ou seus precursores no esfregaço sangüíneo de tilápia do Nilo.Palavras-chave...