Abstract Background: Curcuma longa has biological effects. Its cardiovascular activities are yet to be scientifically studied. Objectives: To investigate the vasorelaxant effects of the aqueous extract of Curcuma longa (AECL). Methods: Aortic annuli of normotensive rats, with or without endothelium, were set up in a data storage system with nutrient solution in recipients, with scientifically recommended temperature, aeration and tension. Over contraction by Phenylephrine, the AECL (1, 3, 10, 30, 100, 300 and 1000 µg/mL) was incubated before and after incubation with atropine or L-name or indomethacin. An AECL concentration-response curve was also built over contractions caused by elevation of extracellular K+. Data were significant when p < 0.05, with GraphPad Prism 6.0 software resolutions. Results: The AECL induced 100% vasorelaxation also in the endothelium-free annuli. The part of the endothelium-dependent effect had EC50 = 4.32 ± 0.05 µg/mL. With inhibition of NO production, the EC50 increased to 126.50 ± 2.35 µg/mL; after inhibition of prostacyclin production, to 124.6 ± 0.05 µg/mL; and after muscarinic blockade, to 437.10 ± 0.2 µg/mL. Opening of K+ channels (relaxation of 56.98%) and VOCC blockade (relaxation of 31.56%) were evident. Conclusion: AECL induced significant vasorelaxation, being more significant in the presence of endothelium. The muscarinic pathway seems to be the main one involved in this effect, followed by the NO production and prostacyclin pathways. The activity in K+ channels by AECL was more significant than its VOCC blockade. The use of other models and tools to study action mechanisms will be important and elucidating.

Abstract INTRODUCTION This aim of this study was to evaluate the antibacterial activity of fractions and isolates of Maytenus guianensis, a plant species used in Amazonian folk medicine. METHODS A disk diffusion technique was used to investigate the antibacterial potential. RESULTS The hexanic fractions and tingenone B isolate showed inhibitory effects against Staphylococcus aureus and Streptococcus pneumoniae. CONCLUSIONS These results indicate the antibacterial potential of this species and will enable future studies to identify novel therapeutic alternatives from this species.

Abstract INTRODUCTION This communication reports the occurrence of Rhodnius neglectus in the State of Acre, Brazil. METHODS An adult male R. neglectus specimen was collected from the Catuaba Experimental Reserve, which is located in the municipality of Senador Guiomard. RESULTS This increases the number of triatomine species reported from the State of Acre to eight and is also the first report of R. neglectus from the Brazilian Western Amazon Region. CONCLUSIONS The occurrence of R. neglectus is alarming because even though the species is wild, it can invade and colonize human dwellings and peridomiciles, thereby increasing Chagas disease transmission.

Abstract INTRODUCTION The occurrence of Triatoma sordida in the Brazilian Western Amazon is reported for the first time. METHODS Triatoma sordida specimens were collected from a Gallus gallus nest in a peridomiciliary area of Senador Guiomard municipality in the state of Acre. RESULTS The number of triatomine species in Acre increased from six to seven with this first report of T. sordida in the Brazilian Western Amazon. CONCLUSIONS The occurrence of T. sordida in Acre is of concern since it is among the most captured triatomines in peridomiciliary environments in Brazil, and carries a high potential for vector transmission.