BackgroundThe reintroduction of sylvatic yellow fever in the state of São Paulo after about six decades was confirmed in the Northwestern region in 2000, where in 2008 there also occurred an important epizootic. The purpose of this study was to investigate the feeding habits of culicids potentially involved in the sylvatic transmission of the virus in this region.MethodsSpecimens were collected in 24 forested localities at ground level with hand nets and mouth aspirators. Collections were made quarterly between October 2006 and July 2008 during daylight hours. Blood-meal identification was carried out in mosquitoes of the tribes Aedini, Mansoniini and Sabethini. The biotin/avidin sandwich ELISA was employed to determine six source types: bird, bovine, equine, rat, human and monkey.ResultsA total of 24,879 females of the three tribes were obtained, 245 (0.98%) of which were engorged. The presence of three different blood sources per engorged female was the predominant situation, and included 35.10% of the total of samples processed. Samples with two or four different sources were represented by 25.31% and 25.71%, of the specimens, respectively, while just 9.39% had only one type and 1.22%, five different sources. Aedes scapularis, Ae. serratus (Group), Psorophora albigenu and Ps. ferox were the most abundant species and accounted for about 95% of the engorged specimens. Of the principal vector species, Haemagogus janthinomys/capricornii was found with bird, bovine and primate blood. These sources were predominant and alternated top ranking as the most frequent source according to the mosquito species and collection site. In general, primate blood was the most prevalent source.ConclusionsThe human population of the region visits this ecotone frequently, which indicates the need for the periodical assessment of vaccination coverage against yellow fever. The frequency of non-human primate blood source in mosquito species that show minor vector importance in yellow fever virus transmission deserves attention. The eclectic feeding habits and some aspects of the interactions between potential vectors and reservoirs of yellow fever may be associated with the habitat fragmentation characteristic of the region. We recommend that further studies on the capacity and vector competence be performed on secondary vectors in extra-Amazonian region.Electronic supplementary materialThe online version of this article (doi:10.1186/s40409-015-0005-z) contains supplementary material, which is available to authorized users.

Background NF-kB (nuclear factor kappa B) is a transcription factor composed of two subunits, p50 and p65, which plays a key role in the inflammatory process. Melatonin has oncostatic, antiangiogenic and antimetastatic properties, and some recent studies have indicated an inhibitory effect of melatonin on NF-kB in some types of cancer. This work aims to investigate the effects of melatonin treatment on the expression of NF-kB in breast and liver cancer models. Methods The breast cancer xenographic model was performed using female Balb/c nude athymic mice injected with MDA-MB-231 cells. The animals were treated with 40 mg/Kg of melatonin for 21 days. Volume of the tumors was measured with a digital capiler. Hepatocarcinoma model was developed by using the HepG2 cells in vitro, treated with 1 mM melatonin for 24 h. The expression of NF-kB protein was verified by immunohistochemistry and immunocytochemistry and quantified by optical densitometry, in vivo study and in vitro study, respectively. NF-kB gene expression was performed by quantitative RT-PCR. Results The breast cancer xenografts nude mice treated with melatonin showed reduced tumor size (P=0.0022). There was a decrease in NF-kB protein staining (P=0.0027) and gene expression (P=0.0185) in mice treated with melatonin. The opposite results were observed for the hepatocarcinoma model. HepG2 cells treated with melatonin showed an increase in the NF-kB immunostaining when compared to control cells (P=0.0042). Conclusion Our results indicated that treatment with melatonin was able to decrease both gene and protein expressions of NF-kB in breast cancer cells and, conversely, increase the transcription factor protein expression in hepatocarcinoma cells. These data highlighted a double role in the expression of NF-kB, depending on the cell type. Further studies are needed to better elucidate the action of melatonin in NF-kB, since this transcription factor acts on different signaling pathways that are fundamental for carcinogenesis.

O objetivo deste estudo foi realizar vistoria em imóveis para identificar condições facilitadoras para a instalação de colônias de triatomíneos. Selecionaram-se localidades caracterizadas pela persistência de infestação durante toda a década de 1990. Realizaram-se pesquisas de triatomíneos em todos os domicílios, confeccionando-se “croquis” do peridomicílio com descrição dos anexos e distância entre cada anexo e o domicílio. Foram vistoriados os imóveis em quatro momentos diferentes. Ensinou-se aos moradores o modo correto de manutenção e limpeza do intradomicílio e peridomicílio. Identificaram-se 72 moradores, com mediana de idade de 41,5 anos. Composto por 65 domicílios, foram identificados 27,6% positivos para triatomíneos, com coleta de 355 exemplares, representados principalmente por T. sordida (97,3%). Os tipos de anexos mais expressivos foram árvores com ninhos (21,8%) e galinheiros (13,8%). A distância média observada dos anexos em relação à moradia foi de 15,7 metros. Houve acréscimo de 8,6% de anexos no período. Não se encontrou relação entre o fato de o morador ser proprietário do imóvel e a infestação por triatomíneos. A instrumentalização da população para práticas educativas adequadas de saúde pode atuar como moderadora do impacto da infestação por vetores da doença de Chagas, o que não foi observado neste estudo, refletindo na qualidade de vida e proteção de novas gerações.