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71.
Sibelle Feitosa da Cunha Xavier Soares Andréia Aguiar Vieira Reinaldo Teixeira Delfino José Daniel Figueroa-Villar 《Bioorganic & medicinal chemistry》2013,21(18):5923-5930
Neurotoxic organophosphorus compounds (OPs), which are used as pesticides and chemical warfare agents lead to more than 700,000 intoxications worldwide every year. The main target of OPs is the inhibition of acetylcholinesterase (AChE), an enzyme necessary for the control of the neurotransmitter acetylcholine (ACh). The control of ACh function is performed by its hydrolysis with AChE, a process that can be completely interrupted by inhibition of the enzyme by phosphylation with OPs. Compounds used for reactivation of the phosphylated AChE are cationic oximes, which usually possess low membrane and hematoencephalic barrier permeation. Neutral oximes possess a better capacity for hematoencephalic barrier permeation.NMR spectroscopy is a very confident method for monitoring the inhibition and reactivation of enzymes, different from the Ellman test, which is the common method for evaluation of inhibition and reactivation of AChE. In this work 1H NMR was used to test the effect of neutral oximes on inhibition of AChE and reactivation of AChE inhibited with ethyl-paraoxon. The results confirmed that NMR is a very efficient method for monitoring the action of AChE, showing that neutral oximes, which display a significant AChE inhibition activity, are potential drugs for Alzheimer disease. The NMR method showed that a neutral oxime, previously indicated by the Ellman test as better in vitro reactivator of AChE inhibited with paraoxon than pralidoxime (2-PAM), was much less efficient than 2-PAM, confirming that NMR is a better method than the Ellman test. 相似文献
72.
Gert Van Hoof Marisa Vieira Maria Gausman Annie Weisbrod 《The International Journal of Life Cycle Assessment》2013,18(8):1568-1580
Purpose
With an ever increasing list of indicators available, life cycle assessment (LCA) practitioners face the challenge of effectively communicating results to decision makers. Simplification of LCA is often limited to an arbitrary selection of indicators, use of single scores by using weighted values or single attribute indicators. These solutions are less attractive to decision makers, since value judgments are introduced or multi-indicator information is lost. Normalization could be a means to narrow the list of indicators by ranking indicators vs. a reference system. This paper shows three different normalization approaches that produce very different ranking of indicators. It is explained how normalization helps maintain a multi-indicator approach while keeping the most relevant indicators, allowing effective decision making.Methods
The approaches are illustrated on a hand dishwashing case study, using ReCiPe as the impact assessment method and taking the European population (year 2000) as the reference situation. Indicators are ranked using midpoint normalization factors, and compared to the ranking from endpoint normalization broken down by midpoint contribution.Results and discussion
Endpoint normalization shows Resources as the most relevant area of protection for this case, closely followed by Human Health and Ecosystem. Broken down by their key driving midpoints, fossil depletion, climate change and, to a lesser extent, particulate matter formation and metal depletion, are most relevant. Midpoint normalization, however, indicates Freshwater Eutrophication, Natural Land Transformation and Toxicity indicators (marine and freshwater ecotoxicity and human toxicity) are most relevant.Conclusions
A three-step approach based on endpoint normalization is recommended to present only the most relevant indicators, allowing more effective decision making instead of communicating all LCA indicators. The selection process breaks out the normalized endpoint results into the most contributing midpoints (relevant indicators) and reports results with midpoint level units. Bias due to lack of data completeness is less of an issue in the endpoint normalization process (compared to midpoint normalization), while midpoint results are less subject to uncertainty (compared to endpoint results). Focusing on the relevant indicators and key contributing unit processes has proven to be effective for non-LCA expert decision makers to understand, use, and communicate complex LCA results. 相似文献73.
Disturbances, elevation, topography and spatial proximity drive vegetation patterns along an altitudinal gradient of a top biodiversity hotspot 总被引:1,自引:0,他引:1
Pedro V. Eisenlohr Luciana F. Alves Luís Carlos Bernacci Maíra C. G. Padgurschi Roseli B. Torres Eduardo M. B. Prata Flavio Antonio M. dos Santos Marco Antônio Assis Eliana Ramos André Luís C. Rochelle Fernando R. Martins Mariana C. R. Campos Fernando Pedroni Maryland Sanchez Larissa S. Pereira Simone A. Vieira José Ataliba M. A. Gomes Jorge Y. Tamashiro Marcos A. S. Scaranello Cora J. Caron Carlos Alfredo Joly 《Biodiversity and Conservation》2013,22(12):2767-2783
The correlation between vegetation patterns (species distribution and richness) and altitudinal variation has been widely reported for tropical forests, thereby providing theoretical basis for biodiversity conservation. However, this relationship may have been oversimplified, as many other factors may influence vegetation patterns, such as disturbances, topography and geographic distance. Considering these other factors, our primary question was: is there a vegetation pattern associated with substantial altitudinal variation (10–1,093 m a.s.l.) in the Atlantic Rainforest—a top hotspot for biodiversity conservation—and, if so, what are the main factors driving this pattern? We addressed this question by sampling 11 1-ha plots, applying multivariate methods, correlations and variance partitioning. The Restinga (forest on sandbanks along the coastal plains of Brazil) and a lowland area that was selectively logged 40 years ago were floristically isolated from the other plots. The maximum species richness (>200 spp. per hectare) occurred at approximately 350 m a.s.l. (submontane forest). Gaps, multiple stemmed trees, average elevation and the standard deviation of the slope significantly affected the vegetation pattern. Spatial proximity also influenced the vegetation pattern as a structuring environmental variable or via dispersal constraints. Our results clarify, for the first time, the key variables that drive species distribution and richness across a large altitudinal range within the Atlantic Rainforest. 相似文献
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76.
Protein markers of Bursaphelenchus xylophilus Steiner & Buhrer, 1934 (Nickle, 1970) populations using quantitative proteomics and character compatibility
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Sergio Ciordia Lee Robertson Susana C. Arcos María Rosa González María del Carmen Mena Paula Zamora Paulo Vieira Isabel Abrantes Manuel Mota Philippe Castagnone‐Sereno Alfonso Navas 《Proteomics》2016,16(6):1006-1014
The Pine Wood Nematode (PWN) Bursaphelenchus xylophilus is a severe forest pathogen in countries where it has been introduced and is considered a worldwide quarantine organism. In this study, protein markers for differentiating populations of this nematode were identified by studying differences among four selected Iberian and one American population. These populations were compared by quantitative proteomics (iTRAQ). From a total of 2860 proteins identified using the public database from the B. xylophilus genome project, 216 were unambiguous and significantly differentially regulated in the studied populations. Comparisons of their pairwise ratio were statistically treated and supported in order to convert them into discrete character states, suggesting that 141 proteins were not informative as population specific markers. Application of the Character Compatibility methodology on the remaining 75 proteins (belonging to families with different biological functions) excludes 27 which are incompatible among them. Considering only the compatible proteins, the method selects a subset of 30 specific unique protein markers which allowed the compared classification of the Iberian isolates. This approach makes it easier search for diagnostic tools and phylogenetic inference within species and populations of a pathogen exhibiting a high level of genetic diversity. 相似文献
77.
Karen Einsfeldt Isis Cavalcante Baptista Juliana Christina Castanheira Vicente Pereira Roberta Eitler Bruno Fabiana Vieira Mello Isabele Campos Costa-Amaral Elaine Sobral da Costa Maria Cecília Menks Ribeiro Marcelo Gerardin Poirot Land Tito Lívio Moitinho Alves Ariane Leites Larentis Rodrigo Volcan Almeida 《PloS one》2016,11(9)
78.
Gleice Cristina Leite Maura Salaroli Oliveira Lauro Vieira Perdig?o-Neto Cristiana Kamia Dias Rocha Thais Guimar?es Camila Rizek Anna Sara Levin Silvia Figueiredo Costa 《PloS one》2016,11(3)
The study investigated the effect of antibiotic combinations against 20 clinical isolates of A. baumannii (seven colistin-resistant and 13 colistin-susceptible) with different resistance mechanisms. Clinical data, treatment, and patient mortality were evaluated. The following methods were used: MIC, PCRs, and outer membrane protein (OMP) analysis. Synergy was investigated using the checkerboard and time-kill methods. Clonality was evaluated by PFGE. Based on clonality, the whole genome sequence of six A. baumannii isolates was analyzed. All isolates were resistant to meropenem, rifampicin, and fosfomycin. OXA-23 and OXA-143 were the most frequent carbapenemases found. Four isolates showed loss of a 43kDa OMP. The colistin-susceptible isolates belonged to different clones and showed the highest synergistic effect with fosfomycin-amikacin. Among colistin-resistant isolates, the highest synergistic effect was observed with the combinations of colistin-rifampicin followed by colistin-vancomycin. All colistin-resistant isolates harbored blaOXA-23-like and belonged to CC113. Clinical and demographic data were available for 18 of 20 patients. Fourteen received treatment and eight patients died during treatment. The most frequent site of infection was the blood in 13 of 14 patients. Seven patients received vancomycin plus an active drug against A. baumannii; however, mortality did not differ in this group. The synergistic effect was similar for colistin-susceptible isolates of distinct clonal origin presenting with the same resistance mechanism. Overall mortality and death during treatment was high, and despite the high synergism in vitro with vancomycin, death did not differ comparing the use or not of vancomycin plus an active drug against A. baumannii. 相似文献
79.
Grazielle R. Goes Peter S. Rocha Aline R. S. Diniz Pedro H. N. Aguiar Carlos R. Machado Leda Q. Vieira 《PLoS neglected tropical diseases》2016,10(4)