109 research outputs found

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43271/1/11046_2005_Article_BF02051463.pd

    Enantiomeric profiling of quinolones and quinolones resistance gene qnrS in European wastewaters

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    Wastewater-based epidemiology (WBE) was applied for the first time in seven cities across Europe with the aim of estimating quinolones consumption via the analysis of human urinary metabolites in wastewater. This report is also the first pan-European study focussed on the enantiomeric profiling of chiral quinolones in wastewater. By considering loads of (fluoro)quinolones in wastewater within the context of human stereoselective metabolism, we identified cities in Southern Europe characterised by both high usage and direct disposal of unused ofloxacin. In Northern European cities, S-(-)-ofloxacin loads were predominant with respect to R-(+)-ofloxacin. Much more potent, enantiomerically pure S-(-)-ofloxacin was detected in wastewaters from Southern European cities, reflecting consumption of the enantiomerically pure antibiotic. Nalidixic acid, norfloxacin and lomefloxacin were detected in wastewater even though they were not prescribed according to official prescription data. S,S-(-)-moxifloxacin and S,S-(-)-moxifloxacin-N-sulphate were detected in wastewater due to metabolism of moxifloxacin. For the first time, average population-normalised ulifloxacin loads of 22.3 and 1.5 mg day 1000 people were reported for Milan and Castellón as a result of prulifloxacin metabolism. Enrichment of flumequine with first-eluting enantiomer in all the samples indicated animal metabolism rather than its direct disposal. Fluoroquinolone loads were compared with qnrS gene encoding quinolone resistance to correlate usage of fluoroquinolone and prevalence of resistance. The highest daily loads of the qnrS gene in Milan corresponded with the highest total quinolone load in Milan proving the hypothesis that higher usage of quinolones is linked with higher prevalence of quinolone resistance genes. Utrecht, with the lowest quinolones usage (low daily loads) had also one of the lowest daily loads of the qnrS gene. However, a similar trend was not observed in Oslo nor Bristol where higher qnrS gene loads were observed despite low quinolone usage

    A Scheme for the Detection and Tracking of People Tuned for Aerial Image Sequences

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    Abstract. This paper addresses the problem of detecting and tracking a large number of individuals in aerial image sequences that have been taken from high altitude. We propose a method which can handle the numerous challenges that are associated with this task and demonstrate its quality on several test sequences. Moreover this paper contains several contributions to improve object detection and tracking in other domains, too. We show how to build an effective object detector in a flexible way which incorporates the shadow of an object and enhanced features for shape and color. Furthermore the performance of the detector is boosted by an improved way to collect background samples for the classifier train-ing. At last we describe a tracking-by-detection method that can handle frequent misses and a very large number of similar objects

    Comparative measurement and quantitative risk assessment of alcohol consumption through wastewater-based epidemiology: An international study in 20 cities

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    Quantitative measurement of drug consumption biomarkers in wastewater can provide objective information on community drug use patterns and trends. This study presents the measurement of alcohol consumption in 20 cities across 11 countries through the use of wastewater-based epidemiology (WBE), and reports the application of these data for the risk assessment of alcohol on a population scale using the margin of exposure (MOE) approach. Raw 24-h composite wastewater samples were collected over a one-week period from 20 cities following a common protocol. For each sample a specific and stable alcohol consumption biomarker, ethyl sulfate (EtS) was determined by liquid chromatography coupled to tandem mass spectrometry. The EtS concentrations were used for estimation of per capita alcohol consumption in each city, which was further compared with international reports and applied for risk assessment by MOE. The average per capita consumption in 20 cities ranged between 6.4 and 44.3. L/day/1000 inhabitants. An increase in alcohol consumption during the weekend occurred in all cities, however the level of this increase was found to differ. In contrast to conventional data (sales statistics and interviews), WBE revealed geographical differences in the level and pattern of actual alcohol consumption at an inter-city level. All the sampled cities were in the "high risk" category (MOE

    Estimation of caffeine intake from analysis of caffeine metabolites in wastewater

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    Caffeine metabolites in wastewater were investigated as potential biomarkers for assessing caffeine intake in a population. The main human urinary metabolites of caffeine were measured in the urban wastewater of ten European cities and the metabolic profiles in wastewater were compared with the human urinary excretion profile. A good match was found for 1,7-dimethyluric acid, an exclusive caffeine metabolite, suggesting that might be a suitable biomarker in wastewater for assessing population-level caffeine consumption. A correction factor was developed considering the percentage of excretion of this metabolite in humans, according to published pharmacokinetic studies. Daily caffeine intake estimated from wastewater analysis was compared with the average daily intake calculated from the average amount of coffee consumed by country per capita. Good agreement was found in some cities but further information is needed to standardize this approach. Wastewater analysis proved useful to providing additional local information on caffeine use
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