Abstract A Penicillium sp. strain was isolated from corroded parts in the Coaracy Nunes hydroelectric power plant in Amapá State, Brazil. Morphological and molecular techniques identified this strain as Penicillium citreosulfuratum Biourge, whose 5.8S-ITS rDNA sequence grouped well in a phylogenetic tree with other Exilicaulis section species of the Penicillium genus. The obtained strain of P. citreosulfuratum ability to form biofilm on the surface of aluminum wires was confirmed by optical and scanning electron microscopy. In plates containing PDA or T&K media, the P. citreosulfuratum strain growth was inhibited around a paper disk containing a highly concentrated solution of copper, iron, or nickel. However, there was no inhibition halo around the paper disk containing aluminum and there was a faint halo around the paper disk containing zinc. This fungus was able to grow in a modified T&K liquid medium containing 50 mM of Al3+ and less efficiently in the same medium but containing 50 mM Zn2+. The essential oils of melaleuca, mint, thyme, and oregano at 100% inhibited the fungus growth. Oregano essential oil inhibited the P. citreosulfuratum strain growth in concentrations as low as 10%. In conclusion, the results show that the obtained strain of P. citreosulfurarum can form a biofilm on aluminum wires, it grows in the presence of a high concentrations of aluminum and zinc, and essential oils can control its growth.

ABSTRACT Diabetes mellitus is a syndrome that reaches more than 382 million people worldwide. It interferes with the metabolism of carbohydrates, causing chronic hyperglycemia. The objective of this study was to evaluate the effect of the Copaifera duckei, Dwyer, Fabaceae, oleoresin on streptozotocin-induced (STZ) diabetic rats. This study was based on the induction of diabetes mellitus by streptozotocin (55 mg/kg, i.p.) in Wistar rats and treated with doses of C. duckei oleoresin (250 and 500 mg/kg, p.o.). Subsequently, the clinical, biochemical and histopathological of the pancreas parameters were evaluated. Gas chromatographic analysis indicated that β-bisabolene (22.29%), β-caryophyllene (21.25%) and α-farnesene (15.58%) sesquiterpenes were the major components of the C. duckei oleoresin. In streptozotocin-induced diabetes mellitus, it was possible to observe that the C. duckei oleoresin treatment had a significant effect (p < 0.001) on the clinical parameters, and that there was a positive improvement. This was attenuated by the urea, creatinine, and transaminases alterations (p < 0.001) observed in animals with diabetes mellitus, as well as the significantly reduced (p < 0.001) values of total cholesterol, triacylglycerides, and glucose. In the histopathological analyses of the pancreas, it was observed that the C. duckei oleoresin was able to restore β-cells and to significantly increase the quantity and diameter of the Langerhans islets (p < 0.05), when compared to the diabetic group. The treatment with C. duckei oleoresin, employed under the conditions of this study, presented antidiabetic activity and can improve the complications found in this syndrome.

A participação dos metais pesados nas reações químicas do metabolismo dos peixes tornou esses elementos um dos principais focos nos estudos de contaminação. O objetivo deste estudo foi determinar as concentrações dos metais Cd, Cr, Cu, Pb, Zn e Hg no tecido muscular de peixes da bacia do rio Cassiporé (Estado do Amapá) e ambiente, visando avaliar os riscos de contaminação. As concentrações de Cd em Plagioscion squamosissimus (1,061 µg g-1) e Pb em Poptella compressa (4,280 µg g-1) apresentaram valores que ultrapassam os limites estabelecidos pela legislação brasileira. As concentrações de Cr em P. compressa (0,937 ± 0,5 µg g-1), Pimelodella cristata (0,463 ± 0,03 µg g-1) e Cyphocharax gouldingi (0,364 ± 0,12 µg g-1), bem como de Hg em P. squamosissimus (0,670 µg g-1), Pseudoplatystoma fasciatum (0,630 µg g-1), Hoplias malabaricus (0,570 µg g-1 e Serrasalmus rhombeus (0,548 µg g-1) foram acima do limite legal. A coluna d'água apresentou altas concentrações de metais pesados em todos os pontos analisados, mostrando uma contaminação dessa bacia. Portanto, essas elevadas concentrações de metais pesados no ambiente e tecido muscular dos peixes indicam um elevado grau de contaminação na bacia do rio Cassiporé e risco a saúde do homem.

Heavy metals participate in chemical reactions of fish metabolism, which makes these elements a major focus on contamination studies. The objective of this study was to determine the concentrations of heavy metals Cd, Cr, Cu, Pb, Zn and Hg in muscle tissue of fish of Cassiporé River Basin (State of Amapá) and environment, aiming at assessing the risk of contamination. The concentrations of Cd in Plagioscion squamosissimus (1.061 µg g-1) and Pb in Poptella compressa (4.280 µg g-1) had values that exceed the boundaries established by Brazilian law. The Cr concentration in P. compressa (0.937 ± 0.5 µg g-1), Pimelodella cristata (0.463 ± 0.03 µg g-1) and Cyphocharax gouldingi (0.364 ± 0.12 µg g-1) and Hg in P. squamosissimus (0.670 µg g-1), Pseudoplatystoma fasciatum (0.630 µg g-1), Hoplias malabaricus (0.570 µg g-1 e Serrasalmus rhombeus (0.548 µg g-1) were above the legal limit. The water column showed high concentrations of heavy metals in all analyzed points, showing a contamination of this river basin. Therefore, the high concentrations of heavy metals in the environment and muscle tissue of fish indicate a high degree of contamination in the Cassiporé river basin and risk to human health.

Foram realizados estudos para avaliar a microestrutura, a dureza e a resistência à corrosão do titânio comercialmente puro-Ti c.p. soldado por laser e utilizado na confecção de prótese sobre implantes. Verificou-se que na soldagem a laser a microestrutura apresentou três regiões distintas: o cordão de solda, a zona afetada pelo calor - ZAC e o metal base. O Ti c.p. possui microestrutura granular, a microestrutura do cordão de solda é mais refinada e de maior dureza do que o metal base. A ZAC obtida por este processo de soldagem foi relativamente pequena quando comparada com o processo de soldagem por brasagem. Os ensaios eletroquímicos mostraram que a região da solda apresentou menor resistência à corrosão em meio de NaCl 0,15 molL-1 à temperatura ambiente.

This research was developed to study the microstructure, the hardness properties and corrosion resistence of the commercial pure titanium-cp Ti to be applied for prosthesis supported by implants submeted to laser welding process. In the welding area was found three different microstructure regions: the weld fusion zone, the heat afected zone - HAZ, and the base metal. The cp Ti revealed a more refined and hardness weld zone microstructure than that base metal area. The HAZ width were smaller when compared with brazing welding process. The eletrochemical experiments showed that the weld region had a lowest corrosion resistance in NaCl 0.15 molL-1 solution at room temperature.