L’utilisation des antibiotiques en médecine vétérinaire : représentations des antibiotiques et de la biosécurité par les éleveurs de porcs

International audienc

Ann N Y Acad Sci

Microarrays have become an increasingly important tool for biotechnology and molecular diagnostics. Despite many advantages, their sensitivity is still insufficient for such tasks as the analysis of small sample quantities and for the detection of alterations in gene expression of low-abundance genes. Accordingly, amplification strategies are necessary. Approaches to amplify the signal intensity include the increase of the number of dye molecules per target through either particle labels or rolling circle amplification, as used for this study

Modelling lead bioaccessibility in urban topsoils based on data from Glasgow, London, Northampton and Swansea, UK

Predictive linear regression (LR) modelling between bioaccessible Pb and a range of total elemental compositions and soil properties was executed for the Glasgow, London, Northampton and Swansea urban areas in order to assess the potential for developing a national urban bioaccessible Pb dataset for the UK. LR indicates that total Pb is the only highly significant independent variable for estimating the bioaccessibility of Pb. Bootstrap resampling shows that the relationship between total Pb and bioaccessible Pb is broadly the same in the four urban areas. The median bioaccessible fraction ranges from 38% in Northampton to 68% in London and Swansea. Results of this study can be used as part of a lines of evidence approach to localised risk assessment but should not be used to replace bioaccessibility testing at individual sites where local conditions may vary considerably from the broad overview presented in this study

Use of a physiologically-based extraction test to estimate the human bioaccessibility of potentially toxic element in urban soils from the city of Glasgow, UK

A simple, two-stage, physiologically based extraction has been applied to assess the human bioaccessibility of potentially toxic elements (PTE) in 20 urban soils from a major UK city. Chromium and iron bioaccessibilities were found to be markedly higher in the intestinal phase, whilst lead and zinc bioaccessibilities were higher in the stomach. Copper and manganese bioaccessibilities were generally similar under both extraction conditions. Principal component analysis was used to study relationships amongst bioaccessible element concentrations and land use. Distinctions could be observed between the distributions of the urban metals— copper, lead and zinc—and metals predominantly of geogenic origin, such as iron. There was no clear delineation between roadside soils and soils obtained from public parks. Bioaccessible analyte concentrations were found to be correlated with pseudototal (aqua regia soluble) analyte concentrations for all elements except iron. Results of the BCR sequential extraction did not, in general, provide a good indication of human bioaccessibility. Comparison of bioaccessible PTE concentrations with toxicological data indicated that lead is the element of greatest concern in these soils but that levels are unlikely to pose a health risk to children with average soil intake