An inventory of heavy metals inputs to agricultural soils in England and Wales

An inventory of heavy metal inputs (Zn, Cu, Ni, Pb, Cd, Cr, As and Hg) to agricultural soils in England and Wales in 2000 is presented, accounting for major sources including atmospheric deposition, sewage sludge, livestock manures, inorganic fertilisers and lime, agrochemicals, irrigation water, industrial by-product 'wastes' and composts. Across the whole agricultural land area, atmospheric deposition was the main source of most metals, ranging from 25 to 85% of total inputs. Livestock manures and sewage sludge were also important sources, responsible for an estimated 37-40 and 8-17% of total Zn and Cu inputs, respectively. However, at the individual field scale sewage sludge, livestock manures and industrial wastes could be the major source of many metals where these materials are applied. This work will assist in developing strategies for reducing heavy metal inputs to agricultural land and effectively targeting policies to protect soils from long-term heavy metal accumulation. (C) 2003 Elsevier Science B.V. All rights reserved.

Anxiety-induced response perseverance and stereotyping change

This study examined anxiety as a potential moderator of stereotype change. Previous work has independently demonstrated an increase in stereotyping under conditions of high anxiety as well as following attempts to suppress stereotypic thought. The combination of these two antecedent conditions might thus be expected to produce an additive increase in stereotyping. In contrast to an additive pattern, however, we observed an interaction between anxiety and suppression task instruction. Whilst both the instruction to suppress (in the absence of anxiety) or anxiety (in the absence of the instruction to suppress) did independently increase stereotyping, when the two co-occurred, there was no change. We explain this interaction by considering work from neuropsychological domain on response perseverance: cognitive overload (one consequence of anxiety) may inhibit the ability to switch between modes of perception. These findings suggest a potentially important moderator for attempts to suppress social stereotypes, and point to the efficacy of integrating work from diverse domains for understanding the operation of executive processes in person perception.

Inhibition of vascular smooth muscle cell proliferation by non-steroidal anti-inflammatory drugs

Abnormal vascular smooth muscle cell (VSMC) proliferation is known to play an important role in the pathogenesis of atherosclerosis, restenosis and instent stenosis. Recent studies suggest that salicylates, in addition to inhibiting cyclooxygenase activity, exert an antiproliferative effect on VSMC growth both in vitro and in vivo. However, whether all non-steroidal anti-inflammatory drugs (NSAID) exert similar antiproliferative effects on VSMCs, and do so via a common mechanism of action, remains unknown. In the present study, we demonstrated that the NSAIDs, aspirin, ibuprofen and sulindac induced a dose-dependent inhibition of proliferation in rat A10 VSMCs (IC50 = 1666 mumol/L, 937 mumol/L and 520 mumol/L, respectively). These drugs did not show significant cytotoxic effects as determined by LDH release assay, even at the highest concentrations tested (aspirin, 5000 mumol/L; ibuprofen, 2500 mumol/L; and sulindac, 1000 mumol/L). Flow cytometric analyses showed that a 48 h exposure of A10 VSMCs to ibuprofen (1000 mumol/L) and sulindac (750 mumol/L) led to a significant G1 arrest (from 68.7 +/- 2.0% of cells in G1 to 76.6 +/- 2.2% and 75.8 +/- 2.2%, respectively, p < 0.05). In contrast, aspirin (2500 mumol/L) failed to induce a significant G1 arrest (68.1 +/- 5.2%). Clearer evidence of a G1 block was obtained by treatment of cells with the mitotic inhibitor, nocodazole (40 ng/ml), for the final 24 h of the experiment. Under these conditions, aspirin still failed to induce a G1 arrest (from 25.9 +/- 10.9% of cells in G1 to 19.6 +/- 2.3%) whereas ibuprofen and sulindac led to a significant accumulation of cells in G1(51.8% +/- 17.2% and 54.1% +/- 10.6%, respectively, p < 0.05). These results indicate that ibuprofen and sulindac inhibit VSMC proliferation by arresting the cell cycle in the G1 phase whereas the effect of aspirin appears to be independent of any special phase of the cell cycle. Irrespective of mechanism, our results suggest that NSAIDs might be of benefit to the treatment of vascular proliferative disorders.

Stereodivergent approach to the asymmetric synthesis of bacillariolides: A formal synthesis of ent-bacillariolide II

Asymmetric synthesis of densely functionalized bicyclic frameworks for entry into bacillariolides I/III and ent-bacillariolide II is reported. The key features are ring-closing metathesis of a pair of diastereomerically related dienes obtained through a stereodivergent route from a R-(+)-glyceraldehyde derivative, transformation of a nonstereoselective cyclopentene ester enolate alkylation process to a completely stereoselective one through alkylation of a bulky ester enolate with a bulky electrophile, and a remote silyloxymethyl group directed epoxidation.

Longitudinal selenium status in healthy British adults: assessment using biochemical and molecular biomarkers

Human selenium (Se) requirements are currently based on biochemical markers of Se status. In rats, tissue glutathione peroxidase-1 (Gpx1) mRNA levels can be used effectively to determine Se requirements; blood Gpx1 mRNA levels decrease in Se-deficient rats, so molecular biology-based markers have potential for human nutrition assessment. To study the efficacy of molecular biology markers for assessing Se status in humans, we conducted a longitudinal study on 39 subjects (age 45 +/- 11) in Reading, UK. Diet diaries (5 day) and blood were obtained from each subject at 2, 8, 17 and 23 weeks, and plasma Se, glutathione peroxidase (Gpx3) enzyme activity, and selenoprotein mRNA levels were determined. There were no significant longitudinal effects on Se biomarkers. Se intake averaged 48 +/- 14 mu g/d. Plasma Se concentrations averaged 1.13 +/- 0.16 mu mol/l. Plasma Se v. energy-corrected Se intake (ng Se/kJ/d) was significantly correlated, but neither Gpx3 activity v. Se intake (ng Se/kJ/d) nor Gpx3 activity v. plasma Se was significantly correlated. Collectively, this indicates that subjects were on the plateaus of the response curves. Selenoprotein mRNAs were quantitated in total RNA isolated from whole blood, but mRNA levels for Gpx1, selenoprotein H, and selenoprotein W (all highly regulated by Se in rodents), as well selenoprotein P, Gpx3, and phospholipid hydroperoxide glutathione peroxidase were also not significantly correlated with plasma Se. Thus selenoprotein molecular biomarkers, as well as traditional biochemical markers, are unable to further distinguish differences in Se status in these Se replete subjects. The efficacy of molecular biomarkers to detect Se deficiency needs to be tested in Se-deficient populations.

The implications of climate policy for the impacts of climate change on global water resources

This paper assesses the implications of climate policy for exposure to water resources stresses. It compares a Reference scenario which leads to an increase in global mean temperature of 4oC by the end of the 21st century with a Mitigation scenario which stabilises greenhouse gas concentrations at around 450ppm CO2e and leads to a 2oC increase in 2100. Associated changes in river runoff are simulated using a global hydrological model, for four spatial patterns of change in temperature and rainfall. There is a considerable difference in hydrological change between these four patterns, but the percentages of change avoided at the global scale are relatively robust. By the 2050s, the Mitigation scenario typically avoids between 16 and 30% of the change in runoff under the Reference scenario, and by 2100 it avoids between 43 and 65%. Two different measures of exposure to water resources stress are calculated, based on resources per capita and the ratio of withdrawals to resources. Using the first measure, the Mitigation scenario avoids 8-17% of the impact in 2050 and 20-31% in 2100; with the second measure, the avoided impacts are 5-21% and 15-47% respectively. However, at the same time, the Mitigation scenario also reduces the positive impacts of climate change on water scarcity in other areas. The absolute numbers and locations of people affected by climate change and climate policy vary considerably between the four climate model patterns.

The efficacy of Salenvac, a Salmonella enterica subsp. Enterica serotype Enteritidis iron-restricted bacterin vaccine, in laying chickens

The protective effect of two vaccination regimes using Salenvac, a commercially available iron-restricted Salmonella enterica subsp. Enterica serotype Enteritidis PT4 bacterin vaccine, was verified in laying birds. Immunization was intramuscular at 1 day old and again at 4 weeks of age (V2), or at 1 day and 4 weeks with a third dose at 18 weeks of age (V3). Challenge S. Enteritidis (5 to 7.5) x 10(7) colony forming units) was given intravenously at 8, 17, 23, 30 and 59 weeks of age. For all age groups, both vaccination regimes reduced significantly the number of tissues and faecal samples that were culture positive for the challenge strain. For laying birds, fewer eggs (P < 0.001) were culture positive for S. Enteritidis after challenge from vaccinated laying birds ( 56/439 batches of eggs) than unvaccinated birds (99/252 batches). The data give compelling evidence that the vaccine is efficacious and may contribute to the reduction of layer infection and egg contamination.

Comparison of the global gene expression profiles produced by methylparaben, n-butylparaben and 17 beta-oestradiol in MCF7 human breast cancer cells

Since the alkyl esters of p-hydroxybenzoic acid (parabens) can be measured intact in the human breast and possess oestrogenic properties, it has been suggested that they could contribute to an aberrant burden of oestrogen signalling in the human breast and so play a role in the rising incidence of breast cancer. However, although parabens have been shown to regulate a few single genes (reporter genes, pS2, progesterone receptor) in a manner similar to that of 17 beta-oestradiol, the question remains as to the full extent of the similarity in the overall gene profile induced in response to parabens compared with 17 beta-oestradiol. The GE-Amersham CodeLink 20 K human expression microarray system was used to profile the expression of 19881 genes in MCF7 human breast cancer cells following a 7-day exposure to 5 x 10(-4) m methylparaben, 10(-5) m n-butylparaben and 10(-8) m 17 beta-oestradiol. At these concentrations, the parabens gave growth responses in MCF7 cells of similar magnitude to 17 beta-oestradiol. The study identified genes which are upregulated or downregulated to a similar extent by methylparaben, n-butylparaben and 17 beta-oestradiol. However, the majority of genes were not regulated in the same way by all three treatments. Some genes responded differently to parabens from 17 beta-oestradiol, and furthermore, differences in expression of some genes could be detected even between the two individual parabens. Therefore, although parabens possess oestrogenic properties, their mimicry in terms of global gene expression patterns is not perfect and differences in gene expression profiles could result in consequences to the cells that are not identical to those following exposure to 17 beta-oestradiol. Copyright (c) 2006 John Wiley & Sons, Ltd.

Intramolecular Diels-Alder furan-mediated synthesis of 8-aryl-3, 4-di-hydroisoquinolin-1(2H)-ones, convenient precursors of indeno[1,2,3-ij]isoquinolines

We describe herein preliminary studies on the Intramolecular Diels-Alder Furan-Mediated Synthesis of 8-Aryl-3, 4-di-hydroisoquinolin-1(2H)-ones that constitutes a new, formal synthesis of Indeno[1,2,3-ij]isoquinolines.