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Ants are considered vectors of several pathogens species, with high adaptability to multiple environments, and can be a risk for immunocompromised patients in hospitals. This study aimed to verify the profile of Gram-positive bacteria carried by formicids in hospital environment. The insects were collected in the emergence room, pulmonology and gastroenterology wards in a public hospital of Porto Velho, Rondonia State, Brazil from March to June, 2012. The isolates were characterized according to Gram stain, identification tests for Staphylococcus, Streptococcus, and Micrococcus genera, and susceptibility profile to antimicrobials. From 130 ants collected, 62% of strains isolated from them were identified as Staphylococcus, 25% as Streptococcus, and 13% as Micrococcus. Relating to antibiotic resistance, 83% of strains were resistant to oxacillin, and 50% to vancomycin. It is concluded that ants are potential mechanical carriers of bacteria, suggesting a nosocomial infection risk and strains highly resistant to antibiotics in hospital environment.

Groundbreaking studies of phlebotomine sand fly populations in Assis Brasil, State of Acre, Brazil, resulted in the collec-tion of 13 new records of phlebotomine sand flies and one previously undescribed species. Lutzomyia naiffi sp. nov. is described here. The new species is similar to Lutzomyia columbiana (Ristorcelli & Van Ty) in measurements and other morphological characters.

This study evaluated the species composition of sand flies and identified potential vectors of Leishmania Ross species in rural areas of Porto Velho, Rondonia State, Brazil. American cutaneous leishmaniasis (ACL) is one of the gravest threats to public health in this state. Sand flies were collected over the course of 2014 and 2015 using HP light traps. Polymerase chain reaction was performed by targeting the Leishmania mkDNA region. In total, 2,344 sand flies were collected, from which 45 species, nine subgenera, and five species group were identified. The most abundant species were Lutzomyia antunesi (Coutinho) (n = 597, 25.47%), Lutzomyia ubiquitalis (Mangabeira) (n = 496, 21.16%), and Lutzomyia octavioi (Vargas) (n = 199, 8.49%). The greatest diversity occurred in the forest environment where the most abundant species were L. antunesi (n = 588, 25.07%), L. ubiquitalis (n = 493, 21.02%), L. octavioi (n = 199, 8.49%), and Lutzomyia flaviscutellata (Mangabeira) (n = 132, 5.63%). Two pools of L. ubiquitalis were positive for Leishmania DNA, which suggests that L. ubiquitalis is a putative vector of leishmaniasis in the municipality of Porto Velho.

O objetivo desse trabalho foi: identificar as espécies de flebotomíneos, estimar a taxa de infecção dos flebotomíneos, identificar os agentes etiológicos envolvidos na transmissão da LTA no município de Assis Brasil, Acre. Foi realizada a PCR para a identificação de espécies de Leishmania em amostras de flebotomíneos e biópsias humanas. Um total de 6.850 exemplares foram capturados pertencentes a 66 espécies de flebotomíneos. As espécies mais abundantes foram Lu. auraensis, Lu. davisi, Lu. choti e Lu. shawi. Trinta e dois pools foram positivos para a presença de DNA de Leishmania com uma prevalência mínima de infecção de 1,85% para Lu. davisi e de 2,05% para Lu. auraensis. As espécies de Leishmania detectadas foram: Le. (Viannia) guyanensis e Le. (V.) braziliensis. Além dessas, outras duas espécies de Leishmania foram encontradas a partir das biópsias de lesões: Le. (V.) shawi e Le. (Le.) amazonenses. A doença foi mais prevalente no sexo masculino e residente na zona rural. Esse é o primeiro registro de Le. (V.) shawi e Le. (L.) amazonenses no Acre. The objectives of this study were: to identify phlebotominae species, to estimate infection rates of phlebotomines, to identify the etiological agents involved in ATL transmission in the municipality of Assis Brasil, Acre. The PCR was used to identify Leishmania species in phlebotomine and human biopsy samples. A total of 6,850 sandflies. comprising 66 species were captured. The most abundant species were Lu. auraensis, Lu. davisi, Lu. choti e Lu. shawi. Thirty-two pools tested positive for the presence of Leishmania DNA, with a minimum infection rate of 1.85% in Lu. davisi and 2.05% in Lu. auraensis. The Leishmania species were identified as Le. (Viannia) guyanensis and Le. (V.) braziliensis. In addition to these, two other Leishmania species were identified from lesion biopsies: Le. (V.) shawi and Le. (Le.) amazonenses. The disease was most common among males (81.6%) e and persons living in rural areas (75.7%). This is the first record of Le. (V.) shawi and Le. (Le.) amazonenses in Acre.

Background 3beta,6beta,16beta-trihydroxylup-20(29)-ene is a lupane triterpene isolated from Combretum leprosum fruit. The lupane group has been extensively used in studies on anticancer effects; however, its possible activity against protozoa parasites is yet poorly known. The high toxicity of the compounds currently used in leishmaniasis chemotherapy stimulates the investigation of new molecules and drug targets for antileishmanial therapy. Methods The activity of 3beta,6beta,16beta-trihydroxylup-20(29)-ene was evaluated against Leishmania (L.) amazonensis by determining the cytotoxicity of the compound on murine peritoneal macrophages, as well as its effects on parasite survival inside host cells. To evaluate the effect of this compound on intracellular amastigotes, cultures of infected macrophages were treated for 24, 48 and 96 h and the percentage of infected macrophages and the number of intracellular parasites was scored using light microscopy. Results Lupane showed significant activity against the intracellular amastigotes of L. (L.) amazonensis. The treatment with 109 μM for 96 h reduced in 80 % the survival index of parasites in BALB/c peritoneal macrophages. At this concentration, the triterpene caused no cytotoxic effects against mouse peritoneal macrophages. Ultrastructural analyses of L. (L.) amazonensis intracellular amastigotes showed that lupane induced some morphological changes in parasites, such as cytosolic vacuolization, lipid body formation and mitochondrial swelling. Bioinformatic analyses through molecular docking suggest that this lupane has high-affinity binding with DNA topoisomerase. Conclusion Taken together, our results have showed that the lupane triterpene from C. leprosum interferes with L. (L.) amazonensis amastigote replication and survival inside vertebrate host cells and bioinformatics analyses strongly indicate that this molecule may be a potential inhibitor of topoisomerase IB. Moreover, this study opens major prospects for the development of novel chemotherapeutic agents with leishmanicidal activity.

Background: Phlebotomine sand flies (Diptera: Psychodidae) are insects of medical importance due to the role that some species play in the transmission of leishmaniasis. This work aimed to study some ecological aspects among sand flies fauna inhabiting two different environments: the várzea (lowland Amazonian forest) and terra firme (upland Amazonian forest), both located in Tefé Municipality, Amazonas State, Braziland to detect Leishmania infection in those phlebotomine populations. Methods: Sand flies were collected using HP light traps. Collection took place over the course of six months: January, February, April, August, September, and October of 2013. To detect natural infection by Leishmania, DNA samples were extracted from female sand flies and submitted to Polymerase Chain Reaction (PCR) targeting the kDNA gene; Leishmania species were identified by PCR-RFLP targeting the hsp70 gene and genetic sequencing. Results: In all, 5,716 individuals were collected, and 46 species were identified. Trichophoromyia ubiquitalis (3,330 - 58.26%) and Nyssomyia antunesi (661 - 11.26%) were the most abundant species. Species richness was greater in terra firme environments (42 species) than in the várzea environments (22 species), and forests ecotopes (43 species) were richer than peridomiciles (28 species). DNA of Leishmania was found in Th. ubiquitalis and Psychodopygus davisi, both of which inhabit the terra firme environment and sequencing analysis confirmed the presence of Leishmania (Viannia) lainsoni DNA in Th. ubiquitalis in Tefé Municipality. Conclusions: The high abundance of Th. ubiquitalis and Ps. davisi and detection of DNA of Leishmania sp. may indicate that both species could be putative vectors for American Cutaneous Leishmaniasis (ACL) in the terra firme environment of Tefé. The sand fly fauna found in várzea is rich and diverse, exhibiting several species, nevertheless the seasonal hydric stress during part of the year that could influence the local diversity, if compared with other studies. This is the first report in Amazonas State of Th. ubiquitalis with presence of L. (V.) lainsoni DNA. © 2015 Pereira et al.; licensee BioMed Central.

Groundbreaking studies of phlebotomine sand fly populations in Assis Brasil, State of Acre, Brazil, resulted in the collection of 13 new records of phlebotomine sand flies and one previously undescribed species. Lutzomyia naiffi sp. nov. is described here. The new species is similar to Lutzomyia columbiana (RistorcelliVan Ty) in measurements and other morphological characters.

INTRODUCTION: Malaria and leishmaniasis are prevalent in tropical regions, which have environmental characteristics that are highly favorable to protozoa and vectors of these diseases; the transmission of these infections in sub-tropical regions, although recognized, represents only a small fraction of cases. Plants are constantly being used in the search for and acquisition of new drugs, and many compounds derived from them have been used to combat various diseases. In this study, we evaluated the action of the dichloromethanolic extract of Myrciaria dubia leaves against the protozoa Plasmodium falciparum, Leishmania amazonensis, Leishmania braziliensis, and Leishmania chagasi through bioassays. METHODS The extract from M. dubia was tested for its anti-P. falciparum activity in an anti-histidine-rich protein II immunosorbent assay. The antileishmanial assays were performed using the resazurin method, while cytotoxicity against human hepatoma (HepG2) strain was determined using the colorimetric MTT [3-(4, 5-dimethyl-2- thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide] method. RESULTS The M. dubia extract presented a half-maximal inhibitory concentration equal to 2.35 (1.05)μg/mL for P. falciparum, 190.73 (6.41) μg/mL for L. amazonensis, and greater than equal to 200µg/mL for L. chagasi and L. braziliensis strains. The cytotoxic concentration for 50% of the cells was above 500μg/mL for HepG2, indicating no toxicity and greater selectivity against parasites. CONCLUSIONS The results obtained indicate the presence of antiplasmodial and leishmanicidal bioactive compounds in the dichloromethanolic extracts of M. dubia leaves, and point towards future studies to elucidate the mechanism of action for each physiological effect.

The sandfly Trichophoromyia auraensis has recently evolved as a proven vector of Leishmania (Viannia) endemic to state of Acre in the north of Brazil. This note is intended to propose a correction in the report of the first occurrence of natural infection of Leishmania (Viannia) in this species. We and the other scientific groups reinforced that Tr. auraensis is a possible vector involved in the transmission of American cutaneous leishmaniasis in Acre, Brazil.