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991.
Eric?Roberto?Guimar?es?Rocha Aguiar Roenick Proveti Olmo Simona Paro Flavia Viana Ferreira Isaque?Jo?o?da?Silva de?Faria Yaovi?Mathias?Honore Todjro Francisco Pereira Lobo Erna Geessien Kroon Carine Meignin Derek Gatherer Jean-Luc Imler Jo?o Trindade Marques 《Nucleic acids research》2015,43(13):6191-6206
Virus surveillance in vector insects is potentially of great benefit to public health. Large-scale sequencing of small and long RNAs has previously been used to detect viruses, but without any formal comparison of different strategies. Furthermore, the identification of viral sequences largely depends on similarity searches against reference databases. Here, we developed a sequence-independent strategy based on virus-derived small RNAs produced by the host response, such as the RNA interference pathway. In insects, we compared sequences of small and long RNAs, demonstrating that viral sequences are enriched in the small RNA fraction. We also noted that the small RNA size profile is a unique signature for each virus and can be used to identify novel viral sequences without known relatives in reference databases. Using this strategy, we characterized six novel viruses in the viromes of laboratory fruit flies and wild populations of two insect vectors: mosquitoes and sandflies. We also show that the small RNA profile could be used to infer viral tropism for ovaries among other aspects of virus biology. Additionally, our results suggest that virus detection utilizing small RNAs can also be applied to vertebrates, although not as efficiently as to plants and insects. 相似文献
992.
993.
Francinaldo Soares Silva Jefferson Mesquita Brito Benedita Maria Costa Neta Shelre Emile Pereira Duarte Lobo 《Memórias do Instituto Oswaldo Cruz》2015,110(6):801-803
Hoover Pugedo light traps were modified for use with green and blue-light-emitting
diodes to trap phlebotomine sandflies in northeastern Brazil. A total of 2,267
specimens belonging to eight genera and 15 species were sampled. The predominant
species were Nyssomyia whitmani(34.41%) and Micropygomyia
echinatopharynx(17.25%).The green LED trap prevailed over the blue and
control lights; however, no statistically significant difference could be detected
among the three light sources. Even without statistical significance, we suggest
using LEDs as an attractant for the capture of sandflies because of several
advantages over the conventional method with incandescent lamps. 相似文献
994.
Jaquelline Carla Valamiel de Oliveira-Silva Girley Francisco Machado-de-Assis Maykon Tavares Oliveira Nívia Carolina Noguieira Paiva Márcio Sobreira Silva Araújo Cláudia Martins Carneiro Olindo Assis Martins-Filho Helen Rodrigues Martins Marta de Lana 《Memórias do Instituto Oswaldo Cruz》2015,110(1):86-94
Trypanosoma cruzi strains from distinct geographic areas show differences in drug
resistance and association between parasites genetic and treatment response has been
observed. Considering that benznidazole (BZ) can reduce the parasite burden and
tissues damage, even in not cured animals and individuals, the goal is to assess the
drug response to BZ of T. cruzi II strains isolated from children of the
Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected
and treated with BZ in both phases of infection were compared with the untreated and
evaluated by fresh blood examination, haemoculture, polymerase chain reaction,
conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in
the acute phase, a significant decrease in parasitaemia was observed for all strains.
Positive parasitological and/or serological tests in animals treated during the acute
and chronic (95.1-100%) phases showed that most of the strains were BZ resistant.
However, beneficial effect was demonstrated because significant reduction (p <
0.05%) and/or suppression of parasitaemia was observed in mice infected with all
strains (acute phase), associated to reduction/elimination of inflammation and
fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals,
what suggest that BZ use may be recommended at least for recent chronic infection of
the studied region. 相似文献
995.
Louisy Sanches dos Santos Camila Azevedo Antunes Cintia Silva dos Santos José Augusto Adler Pereira Priscila Soares Sabbadini Maria das Gra?as de Luna Vasco Azevedo Raphael Hirata Júnior Andreas Burkovski Lídia Maria Buarque de Oliveira Asad Ana Luíza Mattos-Guaraldi 《Memórias do Instituto Oswaldo Cruz》2015,110(5):662-668
Corynebacterium diphtheriae, the aetiologic agent of diphtheria,
also represents a global medical challenge because of the existence of invasive
strains as causative agents of systemic infections. Although tellurite
(TeO32-) is toxic to most microorganisms, TeO32--resistant
bacteria, including C. diphtheriae, exist in
nature. The presence of TeO32--resistance (TeR)
determinants in pathogenic bacteria might provide selective advantages in the natural
environment. In the present study, we investigated the role of the putative
TeR determinant (CDCE8392_813gene) in the virulence
attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in
the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen
species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1
mutant also showed a decrease in both the lethality of Caenorhabditis elegans
and the survival inside of human epithelial cells compared to wild-type
strain. Conversely, the haemagglutinating activity and adherence to and formation of
biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813
gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and
pathogenic potential of C. diphtheriae. 相似文献
996.
Jefferson José da Silva Santos Tereza Magalh?es José Valter Joaquim Silva Junior Andréa Nazaré Monteiro Rangel da Silva Marli Tenório Cordeiro Laura Helena Vega Gonzales Gil 《Memórias do Instituto Oswaldo Cruz》2015,110(5):677-683
Full-length dengue virus (DENV) cDNA clones are an invaluable tool for many studies,
including those on the development of attenuated or chimeric vaccines and on
host-virus interactions. Furthermore, the importance of low passage DENV infectious
clones should be highlighted, as these may harbour critical and unique
strain-specific viral components from field-circulating isolates. The successful
construction of a functional Brazilian low passage DENV serotype 2 full-length clone
through homologous recombination reported here supports the use of a strategy that
has been shown to be highly useful by our group for the development of flavivirus
infectious clones and replicons. 相似文献
997.
998.
999.
Ferreira Charles Francisco Bernardi Juliana Rombaldi da Silva Diego Carrilho de Sá Couto-Pereira Natividade de Souza Mota Carina Krolow Rachel Weis Simone Nardin Pettenuzzo Letícia Kapczinski Flávio Silveira Patrícia Pelufo Dalmaz Carla 《Neurochemical research》2015,40(9):1870-1881
Neurochemical Research - Chronic dietary long-chain polyunsaturated fatty acids (PUFAs) deficiency may lead to changes in cortex and hippocampus neuronal membrane phospholipids, and may be linked... 相似文献
1000.