Virulence factors of piglets septicemia causing Aeromonas hydrophila

This work aims to contribute to determine the resistance profile to different antibiotics (ampicillin, gentamicin, penicillin G, oxytetracycline, lincomycin, neomycin, streptomycin, enrofloxacin, colistin sulfate, trimethoprim, sulfamide, tulathromycin, ceftiofur, amoxicillin/clavulanic acid), to assess genetic determinants associated to aminoglycoside antibiotics resistance, namely the presence of genes encoding acetyltransferases (AAC), phosphotransferases (APH) and nucletildiltranferases (ANT), determined by PCR studies, and to search for potentially pathogenic features as the production of extracellular lipases and proteases and the presence of genes encoding for putative virulence factors as aerolysin and related toxins, lipase proteins and type III secretion system component

Analysis of the Ex Vivo and In Vivo Antiretroviral Activity of Gemcitabine

Replication of retroviral and host genomes requires ribonucleotide reductase to convert rNTPs to dNTPs, which are then used as substrates for DNA synthesis. Inhibition of ribonucleotide reductase by hydroxyurea (HU) has been previously used to treat cancers as well as HIV. However, the use of HU as an antiretroviral is limited by its associated toxicities such as myelosuppression and hepatotoxicity. In this study, we examined the ribonucleotide reductase inhibitor, gemcitabine, both in cell culture and in C57Bl/6 mice infected with LP-BM5 murine leukemia virus (LP-BM5 MuLV, a murine AIDS model). Gemcitabine decreased infectivity of MuLV in cell culture with an EC50 in the low nanomolar range with no detectable cytotoxicity. Similarly, gemcitabine significantly decreased disease progression in mice infected with LP-BM5. Specifically, gemcitabine treatment decreased spleen size, plasma IgM, and provirus levels compared to LP-BM5 MuLV infected, untreated mice. Gemcitabine efficacy was observed at doses as low as 1 mg/kg/day in the absence of toxicity. Higher doses of gemcitabine (3 mg/kg/day and higher) were associated with toxicity as determined by a loss in body mass. In summary, our findings demonstrate that gemcitabine has antiretroviral activity ex vivo and in vivo in the LP-BM5 MuLV model. These observations together with a recent ex vivo study with HIV-1[1], suggest that gemcitabine has broad antiretroviral activity and could be particularly useful in vivo when used in combination drug therapy

An extensive reef system at the Amazon River mouth

Large rivers create major gaps in reef distribution along tropical shelves. The Amazon River represents 20% of the global riverine discharge to the ocean, generating up to a 1.3 x 10(6)-km(2) plume, and extensive muddy bottoms in the equatorial margin of South America. As a result, a wide area of the tropical North Atlantic is heavily affected in terms of salinity, pH, light penetration, and sedimentation. Such unfavorable conditions were thought to imprint a major gap in Western Atlantic reefs. We present an extensive carbonate system off the Amazon mouth, underneath the river plume. Significant carbonate sedimentation occurred during lowstand sea level, and still occurs in the outer shelf, resulting in complex hard-bottom topography. A permanent near-bottom wedge of ocean water, together with the seasonal nature of the plume's eastward retroflection, conditions the existence of this extensive (similar to 9500 km(2)) hard-bottom mosaic. The Amazon reefs transition from accretive to erosional structures and encompass extensive rhodolith beds. Carbonate structures function as a connectivity corridor for wide depth-ranging reef-associated species, being heavily colonized by large sponges and other structure-forming filter feeders that dwell under low light and high levels of particulates. The oxycline between the plume and subplume is associated with chemoautotrophic and anaerobic microbial metabolisms. The system described here provides several insights about the responses of tropical reefs to suboptimal and marginal reef-building conditions, which are accelerating worldwide due to global changes.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Coordenadoria de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERS)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)BrasoilMCTIBrazilian NavyU.S. NSFGordon and Betty Moore Foundation (GBMF)Univ Fed Rio de Janeiro UFRJ, Inst Biol, BR-21941599 Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, COPPE, Inst Alberto Luiz Coimbra Posgrad & Pesquisa Engn, Lab Sistemas Avancados Gestao Prod, BR-21941972 Rio de Janeiro, RJ, BrazilInst Pesquisas Jardim Bot Rio de Janeiro, BR-22460030 Rio De Janeiro, RJ, BrazilUniv Sao Paulo, Inst Oceanog, BR-05508120 Sao Paulo, SP, BrazilUniv Fed Espirito Santo, Dept Oceanog, BR-29199970 Vitoria, ES, BrazilUniv Estadual Norte Fluminense, Lab Ciencias Ambientais, Ctr Biociencias & Biotecnol, BR-28013602 Campos Dos Goytacazes, RJ, BrazilUniv Fed Fluminense, Inst Geociencias, BR-24210346 Niteroi, RJ, BrazilUniv Fed Fluminense, Inst Biol, BR-24210130 Niteroi, RJ, BrazilUniv Fed Rio de Janeiro, Museo Nacl, BR-20940040 Rio De Janeiro, RJ, BrazilFed Univ Para, Inst Estudos Costeiros, BR-68600000 Braganca, PA, BrazilUniv Fed Sao Paulo, Dept Ciencias Mar, BR-11070100 Santos, SP, BrazilUniv Fed Pernambuco, Dept Oceanog, BR-50670901 Recife, PE, BrazilUniv Georgia, Dept Marine Sci, Athens, GA 30602 USAUniv Fed Paraiba, BR-58297000 Rio Tinto, PB, BrazilUniv Estadual Santa Cruz, Dept Ciencias Biol, BR-45650000 Ilheus, BA, BrazilUniv Fed Sao Paulo, Dept Ciencias Mar, BR-11070100 Santos, SP, BrazilU.S. NSF: OCE-0934095GBMF: 2293GBMF: 2928Web of Scienc

Realismo maravilhoso e circularidade cultural: crença no invisível atordoa o pensamento? (Região Bragantina-PA)

O ensaio analisa histórias-depoimentos denominados enquanto “lendas”, “folclores”, “superstições”, “crendices”, “mitos” proferidos por estudantes – oriundos das comunidades interioranas – do curso de Letras da Universidade Federal do Pará (UFPA) dos Campus Universitários das cidades de Bragança e Capanema, Nordeste do Pará. As narrativas formam um conjunto cujo elemento de ligação foi denominado, para este artigo, de realismo maravilhoso, ou seja, apresentam no enredo a mistura do ordinário da vida real, do trabalho e do cotidiano no mundo natural, com o imaginário e o extraordinário do sobrenatural. Para se sustentar esse campo, a interface entre as culturas “popular” e “erudita” demonstrou-se sobejamente importante, posto que quando aqueles adentram à academia levam consigo os saberes “tradicionais” e os amalgamam ao conhecimento científico gerando um produto híbrido, o qual perpassa por um paradoxo na sua gestação: a crença, ou não, no invisível atordoa o pensamento formal racionalista e científico? Eis, o que se argumenta

Gold, palladium and gold-palladium supported on silica catalysts prepared by sol-gel method: synthesis, characterization and catalytic behavior in the ethanol steam reforming

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Noble-metal-based catalysts supported on silica (Au/SiO2, Pd/SiO2 and Au-Pd/SiO2) were prepared by the sol-gel method and were evaluated in the steam reforming of ethanol for hydrogen production. The catalysts were characterized by N-2 physisorption (BET/BJH methods), X-ray diffraction, temperature programmed reduction analysis, H-2 chemisorption, atomic absorption spectrophotometry and Raman spectroscopy. The structural characterization of the Au- and Pd-containing catalysts after calcination showed that the solids are predominantly formed by Au-0, Pd-0 and PdO species and was observed that the metallic Pd dispersion diminished in the presence of Au-0. The results revealed that the catalytic behavior could be influenced by the experimental conditions and the nature of the catalyst employed. The Pd/SiO2 catalyst showed the best performance among the catalysts tested at the highest reaction temperature (600 A degrees C) due to the more effective action of the metallic active phase, which covers a greater area in this sample. At this same reaction temperature, the Au-Pd/SiO2 catalyst showed a significant deactivation, probably due to the lower Pd dispersion presented by this catalyst.672273281Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FINEPFundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Influence of incubation conditions on bacterial production estimates in an estuarine system

This study aimed to assess the influence of incubation conditions in the determination of bacterial production (BP). In order to achieve that goal, experimental setups were performed in situ and in the laboratory under both dark and light conditions. To test spatial and seasonal variations and the different natural light exposure of microorganisms, sampling was performed in two distinct zones of the estuary Ria de Aveiro (Portugal), typifying the marine and brackish water zones of the estuarine system. Denaturing gradient gel electrophoresis analysis of 16S rRNA gene fragments was used to monitor possible alterations in bacterial community composition induced by the incubation conditions. The results showed that BP determined in situ conditions significantly differed from in the laboratory. In the marine zone, a defined pattern of variation was detected, with consistent higher values of BP in laboratory dark conditions. This trend was not present in the brackish water zone. The seasonal and spatial variability of BP observed in field incubations was related to the physical–chemical proprieties of the water column, irradiance levels and the original community composition. The metabolic active profiles of bacteria were substantially different in the several incubation conditions, suggesting that methodological procedure influences the bacterial community composition, and the values of BP reported for aquatic ecosystems could be quite different from the real ones. In the light of these results, we suggest that BP determinations should be conducted under in situ conditions. However, due to execution limitations, BP needs to be frequently determined in the laboratory, and in this case, dark incubations provide more approximate values. This is the method routinely used, and although this incubation condition can cause stimulation of BP, the structure of the bacterial community is more similar to the one obtained with the in situ incubations