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Moreira Sales, Brazil

Coutinho J.O.P.A.,Federal University of Minas Gerais | Silva M.P.S.,Federal University of Minas Gerais | Moraes P.M.,Federal University of Minas Gerais | Monteiro A.S.,Federal University of Minas Gerais | And 3 more authors.
Bioresource Technology | Year: 2013

A strain of Pseudomonas aeruginosa isolated from a site contaminated with refined oil products exhibited demulsification capabilities against Tween 80-Span 80 stabilized oil-in-water (O/W), Tween 80-stabilized water-in-oil (W/O) model emulsions (kerosene-water), and an industrial emulsion (Daido Dairoll PA-5A). GC-MS analysis confirmed the presence of fatty acids and carbohydrates in the extracellular biodemulsifier. The demulsifying activity of cells and culture supernatants was favored by growth in media containing 1% diesel oil. There was a correlation between culture age, de-emulsification and cellular hydrophobicity, and highest activities were observed for cells and supernatants from 96-h cultures. Activity increased with addition of up to 60. mg cells or 300. μL supernatant to emulsions. The activity was relatively stable at 20-40. °C and to freezing, but was reduced by 69% by washing the cells with chloroform-methanol-water. This demulsifier has potential for application in biotreatment of emulsified oily wastewaters to promote recovery and/or degradation of oil. © 2012 Elsevier Ltd. Source

de Carvalho G.L.X.,Federal University of Ouro Preto | Moreira L.E.,University of Vale do Rio Doce | Pena J.L.,Federal University of Minas Gerais | Marinho C.C.,Federal University of Ouro Preto | And 2 more authors.
Memorias do Instituto Oswaldo Cruz | Year: 2012

This study compares the diagnostic accuracy of the TF-Test ® (TFT) for human parasitosis with results obtained using the traditional Kato-Katz (KK), Hoffman-Pons-Janer (HPJ), Willis and Baermann-Moraes (BM) techniques. Overall, four stool samples were taken from each individual; three alternate-day TFT stool samples and another sample that was collected in a universal container. Stool samples were taken from 331 inhabitants of the community of Quilombola Santa Cruz. The gold standard (GS) for protozoa detection was defined as the combined results for TFT, HPJ and Willis coproscopic techniques; for helminth detection, GS was defined as the combined results for all five coproscopic techniques (TFT, KK, HPJ, Willis and BM). The positivity rate of each method was compared using the McNemar test. While the TFT exhibited similar positivity rates to the GS for Entamoeba histolytica/dispar (82.4%) and Giardia duodenalis (90%), HPJ and Willis techniques exhibited significantly lower positivity rates for these protozoa. All tests exhibited significantly lower positivity rates compared with GS for the diagnosis of helminths. The KK technique had the highest positivity rate for diagnosing Schistosoma mansoni (74.6%), while the TFT had the highest positivity rates for Ascaris lumbricoides (58.1%) and hookworm (75%); HPJ technique had the highest positivity rate for Strongyloides stercoralis (50%). Although a combination of tests is the most accurate method for the diagnosis of enteral parasites, the TFT reliably estimates the prevalence of protozoa and selected helminths, such as A. lumbricoides and hookworm. Further studies are needed to evaluate the detection accuracy of the TFT in samples with varying numbers of parasites. Source

Coelho E.R.C.,University of Sao Paulo | Vazzoler H.,University of Sao Paulo | Leal W.P.,University of Vale do Rio Doce
Engenharia Sanitaria e Ambiental | Year: 2012

Atrazine is one of the most widely herbicides used in the world, being found in surface water and groundwater. It belongs to the s-triazines class classified as possible carcinogenic potential and toxicity presents as an endocrine disruptor. The acknowledged limitation of the water treatment processes, which employ chemical coagulation in atrazine removal and the risks to health, has motivated this work taking into regards the adsorption of activated carbon as an alternative technology. The experimental study consisted of physical characterization of activated carbon and of adsorption tests in waters of different organic content. It was possible to verify the capacity of activated carbon to remove atrazine, and the adsorption mechanism was influenced by the quality variation of water matrices generating isotherms with different characteristics. Source

The valley from sweet river - VRD has motivated research in several areas of knowledge on the part of domestic and foreign researchers. The interest is attracted by the variety of overlapping social and environmental processes, socio-economic, socio-cultural and political. The VRD remained as open border until mid-twentieth century, when finally ended the availability of land and waxed forward pioneer. Concomitant to the settlement, economic occupation and formation of urban areas, if implemented by state action major investment projects, particularly in the areas of steel and mining. If for actors linked to modernize the border was seen as depository of natural resources to the people who came with several hopes the border was a promised land. In the case of VRD, the pioneer front, common phenomenon in Brazilian history, was impacted by territorial large capital investment, thus defined a particular historical dynamics. The end of the border was marked by the first signs of whether it is an unsustainable process, whose outcome is the social and environmental collapse. However, this does not arise for those involved, who insist on playing a vainglorious vision. Therefore, this article deals with the landscape view, the nature of idea, the narratives on the border and discourse over the territory, that is, cultural buildings, written ideas and discourses on the VRD. Source

De Oliveira Fraga L.A.,Uniformed Services University of the Health Sciences | De Oliveira Fraga L.A.,University of Vale do Rio Doce | Torrero M.N.,Uniformed Services University of the Health Sciences | Tocheva A.S.,Uniformed Services University of the Health Sciences | And 2 more authors.
Journal of Infectious Diseases | Year: 2010

During natural schistosome infection, the induction of T helper type 2 (Th2) responses has been ascribed to parasite eggs, because exposure of the host to this life-cycle stage elicits a polarized Th2 response to egg antigens. In the present study, we show that schistosome worms also elicit systemic, antigen-specific type 2 responses during prepatent infection, before egg deposition begins. CD4+ T cells producing interleukin (IL)-4 were induced by both male and female worms during single-sex infections, demonstrating that this response is independent of exposure to eggs. The Th2 response was accompanied by production of immunoglobulin E and the sensitization of circulating basophils to produce additional IL-4 in response to schistosome antigens. Together, our data show that schistosome worms establish an immunologic milieu where CD4+ T cells and basophils are both primed to produce IL-4 before eggs are laid, suggesting that worms play a role in estab-lishment of the Th2 response that is critical for host survival and parasite transmission. Source

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