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Recently, we found acetylcholinesterase (AChE) activity in the ciliate protozoan Paramecium primaurelia. As in the slime mould Dictyostelium discoideum the presence of a serine esterase was found with strong sequence identity to Torpedo AChE, we extended to D. discoideum the investigation on the characterization and possible functions of cholinesterases (ChEs). In amoeboid cells, histochemical, biochemical, and electrophoresis analyses evidenced both a ChE activity able to hydrolyze the substrate PrTChI, and AChE (E.C. 3.1.1.7.) activity similar to Electrophorus electricus AChE. Conversely, butyrylcholinesterase activity was nearly absent, according to our previous results on P. primaurelia. Moreover, the possibility to utilize D. discoideum in a bioassay for the pre-chemical screening both of moist environments and fresh waters, in relation to the occurrence of the neurotoxic organophosphate drugs, such as "basudin", inhibiting ChE activity, was investigated. Exposure to basudin inhibited propionylcholinesterase (PrChE) activity in a dose-dependent manner in the range 10(-1)-10(-7) M (60% at 10(-4) M), without any significant effect on AChE activity. PrChE activity was inhibited slightly by 10(-5) M eserine, and reduced significantly both by 10(-5) M iso-OMPA and BW284C51, classically used to discriminate the different ChE molecular forms. The effects on cell morphology, cell density, and differentiation were evaluated in cultures exposed to PrTChI 10(-5) M or basudin 10(-4) M for a three-day period. The PrTChI-exposed sample exhibited cell morphology, cell density, ability to aggregate, and to form fruiting bodies similar to the control; whereas, the basudin-exposed sample showed anomalies in cell morphology and lower cell density than the control, together with inability to aggregate. 相似文献
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Heavy metals in agricultural soils from Piedmont,Italy. Distribution,speciation and chemometric data treatment 总被引:8,自引:0,他引:8
The distribution and speciation of heavy metals in five agricultural soils of Piedmont Region (north-western Italy) were investigated. Ten metals, namely Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Ti and Zn were considered. Analytical determinations were performed by atomic emission or atomic absorption spectroscopy after microwave sample dissolution in acid solution. Total metal concentrations fit in the typical concentration ranges for unpolluted soils, with the exception of cadmium and lead content in some horizons. The effect of sampling depth on concentrations was discussed. Speciation studies were carried out by applying Tessier's procedure, which allows to subdivide the total metal content into five fractions, representing portions bound to different components of the soil. Moreover, the element labilities in two soils were evaluated by extraction with EDTA. Correlations among the variables and/or similarities among the sampling points were identified by principal component analysis and hierarchical cluster analysis. 相似文献
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Federica Mainente Caterina Fratea Barbara Simonato Gianni Zoccatelli Corrado Rizzi 《Journal of Agricultural and Environmental Ethics》2017,30(2):275-285
Food allergy represents an increasing public health issue, and a large number of food control authorities have provided regulations aimed to minimize the risk of allergic reaction for sensitized consumers. The Food and Agriculture Organization of the United Nations together with the World Health Organization established the Codex Alimentarius Commission whose main goal is to protect the consumers’ health. To purse this task the Commission listed the foods and ingredients causing the most severe allergic reactions that should be labelled. It has been reported that some cases of specific foods hypersensitivity display a different prevalence among different Countries. Thus, the European Union drew up a list of mandatory allergens (that must be labelled) longer than that provided by Codex Alimentarius. As a consequence of the complexity of the legal phraseology of the European Union (EU) and/or European Community (EC) the Regulations and/or Directives were differently translated in all EC/EU official languages determining possible misinterpretations of the legislation. Moreover, food labelling regulations were also established with the goal to promote the consumers’ conscious choice about what they eat. Starting from the case of the fermented beverages, we analysed the European legislative scenario concerning the allergen labelling of the last fifteen years, highlighting that mistranslations, misinterpretations and lack of information in the EU Regulations might lead to health and ethical issues. 相似文献
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Montoneri E Boffa V Savarino P Perrone D Ghezzo M Montoneri C Mendichi R 《Waste management (New York, N.Y.)》2011,31(1):10-17
As previous work proposed commercial expectations for soluble bio-organic substances (SBO) isolated from compost of urban food, gardening and park trimming residues as chemical auxiliaries, nine urban bio-wastes (BW) treated by aerobic and anaerobic digestion for 0-360 days were used to extract SBO and investigate source variability effects on product chemical composition and properties. The bio-wastes were collected over a 13732 km2 area populated by 2.9 millions from 565 municipalities. The SBO were characterized by their content of different C types and functional groups and by their distribution coefficient (KPEGW) between polyethylene glycol and water. A significant linear correlation was found between KPEGW and the lipophilic/hydrophilic C ratio. The investigated SBO exhibited up to sixfold change of KPEGW demonstrating that BW available from densely populated urban areas are an interesting exploitable source of a wide variety of potential products for the chemical market. 相似文献
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Annibale?BiggeriEmail author Massimo?Bonannini Dolores?Catelan Fabio?Divino Emanuela?Dreassi Corrado?Lagazio 《Environmental and Ecological Statistics》2005,12(4):397-409
In this work we propose a Bayesian ecological analysis in which a latent variable summarizes data on emissions of atmospheric
pollutants. We specified a hierarchical Bayesian model with spatially structured and unstructured random terms with a nested
latent factor model. This can be considered a combination of the convolution spatial model of Besag et al. (1991) and an ecological regression analysis in which a latent variable plays the role of the covariate. The unified approach allows
to proper account for the uncertainty in the latent score estimation in the regression analysis. The Bayesian Latent Factor
model is used to summarize the information on environmental pressure derived from three stressors: Carbon Monoxide, Nitrogen
Oxides and Inhalable Particles. We found evidence of positive correlation between Lung cancer mortality and environmental
pressure indicators, in males, Tuscany (Italy), 1995–1999. Environmental pressure seems to be restricted to fourteen municipalities
(top 5% of the Latent Factor distribution). The model identified two areas with high point source emissions. 相似文献
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Marco Ostoich Emilia Aimo Daniel Fassina Jvan Barbaro Marina Vazzoler Corrado Soccorso Chiara Rossi 《Environmental science and pollution research international》2011,18(2):247-259