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.
Enk M.J.,University of Vale do Rio Doce |
Rodrigues N.B.,University of Vale do Rio Doce
PLoS ONE | Year: 2012
Schistosomiasis caused by Schistosoma mansoni, one of the most neglected human parasitoses in Latin America and Africa, is routinely confirmed by microscopic visualization of eggs in stool. The main limitation of this diagnostic approach is its lack of sensitivity in detecting individual low worm burdens and consequently data on infection rates in low transmission settings are little reliable. According to the scientific literature, PCR assays are characterized by high sensitivity and specificity in detecting parasite DNA in biological samples. A simple and cost effective extraction method for DNA of Schistosoma mansoni from urine samples in combination with a conventional PCR assay was developed and applied in an endemic area. This urine based PCR system was tested for diagnostic accuracy among a population of a small village in an endemic area, comparing it to a reference test composed of three different parasitological techniques. The diagnostic parameters revealed a sensitivity of 100%, a specificity of 91.20%, positive and negative predictive values of 86.25% and 100%, respectively, and a test accuracy of 94.33%. Further statistical analysis showed a k index of 0.8806, indicating an excellent agreement between the reference test and the PCR system. Data obtained from the mouse model indicate the infection can be detected one week after cercariae penetration, opening a new perspective for early detection and patient management during this stage of the disease. The data indicate that this innovative PCR system provides a simple to handle and robust diagnostic tool for the detection of S. mansoni DNA from urine samples and a promising approach to overcome the diagnostic obstacles in low transmission settings. Furthermore the principals of this molecular technique, based on the examination of human urine samples may be useful for the diagnosis of other neglected tropical diseases that can be detected by trans-renal DNA. © 2012 Enk et al.
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.
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.
VanWey L.K.,Brown University |
Guedes G.R.,Indiana University Bloomington |
Guedes G.R.,University of Vale do Rio Doce |
D'Antona A.O.,University of Campinas
Population and Environment | Year: 2012
One of Daniel Hogan's lasting impacts on international demography community comes through his advocacy for studying bidirectional relationships between environment and demography, particularly migration. We build on his holistic approach to mobility and examine dynamic changes in land use and migration among small farm families in Altamira, Pará, Brazil. We find that prior area in either pasture or perennials promotes out-migration of adult children, but that out-migration is not directly associated with land-use change. In contrast to early formulations of household life cycle models that argued that aging parents would decrease productive land use as children left the farm, we find no effect of out-migration of adult children on land-use change. Instead, remittances facilitate increases in area in perennials, a slower to pay off investment that requires scarce capital, but in pasture. While remittances are rare, they appear to permit sound investments in the rural milieu and thus to slow rural exodus and the potential consolidation of land into large holdings. We would do well to promote the conditions that allow them to be sent and to be used productively to keep families on the land to avoid the specter of extensive deforestation for pasture followed by land consolidation. © 2011 Springer Science+Business Media, LLC.
de Alvarenga D.G.,University of Vale do Rio Doce |
Escalda P.M.F.,University of Vale do Rio Doce |
da Costa A.S.V.,University of Vale do Rio Doce |
Monreal M.T.F.D.,Federal University of Mato Grosso do Sul
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2010
Introduction: Visceral leishmaniasis is a public health problem, with lethality reaching 10%. The recommended drug treatment is methylglucamine antimoniate. This study aimed to evaluate drug use for cases of visceral leishmaniasis treated at the Infectology Clinic of the Campo Grande University Hospital Center, State of Mato Grosso do Sul. Methods: To collect data, we examined the medical records of 76 patients with a diagnosis of visceral leishmaniasis treated at this Infectology Clinic. Results: The medical files of 76 patients (56 men and 20 women; 28.9%) showed comorbidities. The first choice drug for 88.2% of the patients was N-methylglucamine antimoniate, with a fatal outcome for 18.4%. Survival analysis showed a statistically significant difference between patients with and without comorbidities (p <0.0001) and with comorbidities who used Glucantime® (p < 0.0009). The fatality rate of 18.4% indicates the low efficiency of the healthcare measures used. Conclusions: The results suggest that the prognosis becomes poor when associated with the presence of comorbidities, and that the treatment needs to be carefully administered to minimize mortality.
Ferreira G.F.,Federal University of Minas Gerais |
Baltazar L.M.,Federal University of Minas Gerais |
Alves Santos J.R.,Federal University of Minas Gerais |
Monteiro A.S.,University of Vale do Rio Doce |
And 3 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2013
Although the most accepted mechanisms of action of amphotericin B and azoles are related toergosterol, it is possible that these drugs have other effects on the fungal cell. In the present study, the role of endogenous reactive oxygen species (ROS) and peroxynitrite produced by azoles and amphotericin B in the fungus Cryptococcus gattii were examined. We studied distinct parameters to evaluate the effect of oxidative and nitrosative stresses induced by these drugs in C. gattii cells: lipid peroxidation, ergosterol content, ROS and peroxynitrite production, enzymatic activity of the antioxidant system and the in vitro interaction of antifungal drugs with a peroxidase inhibitor, a superoxide dismutase inhibitor and a peroxynitrite scavenger. The data demonstrated that itraconazole led to ROS formation and lipid peroxidation in C. gattii cells in the early stages of the treatment; this did not occur with fluconazole. This phenomenon strongly increased the activities of enzymes of the antioxidant system. These results were confirmed by synergism observed between the catalase inhibitor and itraconazole. Amphotericin B caused lipid peroxidation in C. gattii cells through a greatly enhanced production of oxidative and nitrosative radicals with increased peroxidase activity. These data were confirmed by the synergism between the catalase/superoxide dismutase inhibitors and amphotericin B. In addition, the effect of this antifungal was antagonized by the peroxynitrite scavenger. Oxidative and nitrosative bursts play an important role in the antifungal activity of itraconazole and amphotericin B against C. gattii. © The Author 2013. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.
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.
Espindola H.S.,University of Vale do Rio Doce
Fronteiras | Year: 2015
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.
de Assis E.M.,University of Vale do Rio Doce |
de Olivieria R.C.,Coodenacao Tecnica Operacional Maxakali |
Moreira L.E.,President Antônio Carlos University |
Pena J.L.,Federal University of Minas Gerais |
And 2 more authors.
Cadernos de Saude Publica | Year: 2013
A prevalence survey using the TF-Test technique to identify intestinal parasites was conducted in the Maxakali indigenous villages in Minas Gerais State, Brazil. Stool samples were collected on three alternating days, in separate tubes, containing 10% formalin, and unified in a laboratory by double filtering centrifugation. Samples of sediment aliquot were prepared in triplicate and examined by microscope (10x and 40x) for eggs, cysts, and larvae. Prevalence of parasites (89.5%) and polyparasitism (46%) were similar by sex and age, but varied by village. Prevalent species were: Entamoeba histolytica/Entamoeba dispar (48.9%), Giardia duodenalis (32%), Entamoeba coli (40.8%), Endolimax nana (10.3%), hookworms (37.9%), Schistosoma mansoni (23.7%), Hymenolepis nana (18.6%), Strongyloides stercoralis (5.4%), Ascaris lumbricoides (4.9%), and Trichuris trichiura (0.5%). The Maxakali population lives in socially vulnerable conditions, and government agencies need to introduce measures to improve sanitation infrastructure and health education.