Elisabetta Corradi

Application of land use regression modelling to assess the spatial distribution of road traffic noise in three European cities

Noise prediction models and noise maps are used to estimate the exposure to road traffic noise, but their availability and the quality of the noise estimates is sometimes limited. This paper explores the application of land use regression (LUR) modelling to assess the long-term intraurban spatial variability of road traffic noise in three European cities. Short-term measurements of road traffic noise taken in Basel, Switzerland (n=60), Girona, Spain (n=40), and Grenoble, France (n=41), were used to develop two LUR models: (a) a “GIS-only” model, which considered only predictor variables derived with Geographic Information Systems; and (b) a “Best” model, which in addition considered the variables collected while visiting the measurement sites. Both noise measurements and noise estimates from LUR models were compared with noise estimates from standard noise models developed for each city by the local authorities. Model performance (adjusted R2) was 0.66–0.87 for “GIS-only” models, and 0.70–0.89 for “Best” models. Short-term noise measurements showed a high correlation (r=0.62–0.78) with noise estimates from the standard noise models. LUR noise estimates did not show any systematic differences in the spatial patterns when compared with those from standard noise models. LUR modelling with accurate GIS source data can be a promising tool for noise exposure assessment with applications in epidemiological studies.

Differences in indoor versus outdoor concentrations of ultrafine particles, PM2.5, PMabsorbance and NO2 in Swiss homes

Indoor air quality is a growing concern as we spend the majority of time indoors and as new buildings are increasingly airtight for energy saving purposes. For a better understanding of residential indoor air pollution in Switzerland we conducted repeated 1–2-week-long indoor and outdoor measurements of particle number concentrations (PNC), particulate matter (PM), light absorbance of PM2.5 (PMabsorbance) and nitrogen dioxide (NO2). Residents of all homes were enrolled in the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA). Indoor levels were comparable in urban areas and generally low in rural homes. Average indoor levels were 7800 particles/cm3 (interquartile range=7200); 8.7 μg/m3 (6.5) PM2.5 and 10.2 μg/m3 (11.2) NO2. All pollutants showed large variability of indoor/outdoor ratios between sites. We observed similar diurnal patterns for indoor and outdoor PNC. Nevertheless, the correlation of average indoor and outdoor PNC between sites as well as longitudinal indoor/outdoor correlations within sites were low. Our results show that a careful evaluation of home characteristics is needed when estimating indoor exposure to pollutants with outdoor origin.

Comprehensive analysis of Cirsium spinosissimum Scop., a wild alpine food plant

Plants which have been traditionally eaten by alpine populations may provide new opportunities of agricultural development for mountain regions. In this context we investigated the chemical composition of Cirsium spinosissimum (Asteraceae), a perennial thistle. Its receptacles were eaten by shepherds in Valais (Switzerland). Extracts of aerial parts were subjected to a comprehensive metabolite profiling, using a dereplication platform, combining HPLC-PDA-MS and offline microprobe NMR analysis. Twenty compounds, including various phenolic glycosides, a monoterpene lactone, a spermine derivative, and fatty acids, could be identified online, or after targeted isolation. The total phenolic content was determined, and the major flavonoids were quantitatively assessed in fresh receptacles by HPLC-PDA analysis. In addition, substances relevant for nutrition, such as β-carotene, fatty acids, ascorbic acid, and minerals, were quantified. The ethanolic extract of the receptacles showed no sign of cytotoxicity when tested in Caco-2 cells.

New Acylated Flavonol Glycosides and a Phenolic Profile of Pritzelago alpina, a Forgotten Edible Alpine Plant

Thirteen acylated flavonoid glycosides, 1–13, including eleven new congeners, 3–13, were isolated from the aerial parts of Pritzelago alpina (Brassicaceae) by a combination of column chromatography on Sephadex LH‐20, and preparative and semi‐preparative HPLC. The structures were established by extensive NMR and MS experiments in combination with acid hydrolysis and sugar analysis by GC/MS. The new compounds were shown to be kaempferol and quercetin glycosides acylated for most of them by a branched short chain fatty acid or a hydroxycinnamic acid residue on the sugar portion. As shown by a HPLC‐DAD analysis of a MeOH extract, these compounds are the main phenolic constituents in the aerial parts of the plant.

Metabolite Profile and Antiproliferative Effects in HaCaT Cells of a Salix reticulata Extract

Phenolic constituents of Salix reticulata (Salicaceae) and antiproliferative activity of an extract and individual compounds were investigated in immortalized human non-tumorigenic keratinocytes (HaCaT). A MeOH extract from aerial parts afforded several flavonoids, including luteolin and apigenin glycosides (2-5 and 9) and catechin (1), two procyanidin fractions, and the phenolic glucosides picein (6), triandrin (7), and salicortin (8). In an adenosine triphosphate assay, the MeOH extract reduced cell viability by approximately 60 % at a concentration of 100 µg/mL. Cell proliferation was assessed with a BrdU incorporation ELISA assay. The extract inhibited proliferation of HaCaT cells in a concentration-dependent manner, with approximately 50 % inhibition at 100 µg/mL. In time-lapse assays, the extract showed distinct inhibitory effects on cell migration at concentrations of 12.5, 25, and 50 µg/mL. The activity of selected constituents was also determined. Luteolin-7-O-β-glucuronide (3) significantly inhibited cell proliferation at concentrations of 10 and 50 µM. In contrast, luteolin-7-O-β-glucopyranoside (2) and a procyanidin fraction (P1) had only weak effects, while picein (6) and salicortin (8) did not affect cell proliferation. Luteolin-7-O-β-glucuronide (10 µM) and, to a lesser extent, the procyanidin fraction (10 µg/mL) also inhibited cell migration.