36 research outputs found

    Lovastatin, but not orlistat, reduces intestinal polyp volume in an Apc(Min/+) mouse model

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    The statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCoAR) and orlistat, an inhibitor of fatty acid synthase (FAS), inhibit tumor cell growth by restricting cholesterol and fatty acid synthesis, respectively. We previously demonstrated that an omega (ω)-3 polyunsaturated fatty acid (PUFA)- or olive oil-enriched diet reduced the polyp number and volume in ApcMin/+ mice. This phenomenon was associated with a significant inhibition of FAS and HMGCoAR, as well as an increase in the estrogen receptor (ER)β/α ratio. Herein, we evaluated the effect of lovastatin and orlistat on polyp development and ER expression in ApcMin/+ mice, in order to confirm previous data obtained with ω-3-PUFAs and olive oil. As expected, the use of lovastatin and orlistat significantly reduced HMGCoAR and FAS enzymatic activities and gene expression in colonic tissues, but did not affect the number of intestinal polyps, while there was a statistically significant reduction in polyp volume only in the mouse group treated with lovastatin. In the mice receiving orlistat, we observed a significant increase in cell proliferation in the polyp tissue, as well as enhanced expression of ERα. Moreover, the overexpression of ERα was associated with a statistically significant increase in PES1, Shh and Gli1 protein levels, considered ERα-related molecular targets

    Could persistent organic pollutants affect future generations of sea turtles by maternal transfer? First results for Caretta caretta nests along the North-Western coast of Italy

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    Since 2013, loggerhead sea turtle (Caretta caretta, Linnaeus 1758) nesting has been observed further north along the Italian coast, reaching the Tuscan coast (NW Mediterranean Sea). The four nesting events that occurred in Tuscany in the summer of 2019 spurred the scientific community to monitor these occurrences more carefully, following them from egg deposition to hatching. This provided an opportunity to collect samples for conducting multidisciplinary investigations, including the toxicological investigations of the biological material collected from the four nests. The aim of this study was to conduct an initial assessment of persistent organic pollutants in the eggs laid in Tuscany, aiming to establish a baseline on this topic for subsequent nesting events that have occurred until today. Organochlorine compounds (OCs), specifically polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its metabolites, and hexachlorobenzene (HCB), were analyzed and detected in unhatched eggs, embryos, and chorio-allantoic membranes (CAMs). OCs were detected in all samples, with PCBs > DDTs ≫ HCB. A significant spatial variation in pollutant levels and profiles among sea turtle nesting locations was found. Embryos showed higher levels of contamination than egg contents regardless of the developmental stages. Depth of the laying chamber and egg mass were not significant factors in OC bioaccumulation. For the first time in the Mediterranean Sea, this study assessed the role of CAM in the transfer of contaminants to the embryo. Overall, the OC levels found were lower compared to the results from other studies conducted worldwide on loggerhead sea turtle biological material. This was the first assessment of nest biological material for the North-Western coast of Italy

    Pollution, Health and Life Expectancy: How Environmental Policy Can Promote Growth

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    This article investigates the influence of environmental policy on growth assuming that the channel of transmission relies on the link between pollution, health and the survival probability, in an overlapping generations model à la Blanchard (1985) where growth is driven by a mechanism à la Romer (1986). We demonstrate that environmental policy has an ambiguous effect on growth in the steady-state when the detrimental impact of pollution on health and lifetime is taken into account: for low levels of taxation, environmental policy promotes growth while it is harmful to growth for high levels. Furthermore, we show that the environmental policy is more likely to promote growth (i.e. it stimulates growth for a wider range of environmental taxes) when public expenditures in health and/or the impact of pollution on health are important. Finally, using numerical simulations, we find that for the value of parameters chosen the environmental policy will be more likely to harm growth when agents smooth consumption over time

    The Rule of the Jungle in Pakistan: A Case Study on Corruption and Forest Management in Swat

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    Corruption in the forest sector of Swat, Pakistan is impairing the sustainable management of forest. We analyze corruption in a case study setting against the backdrop of the reform options that are most often cited as possible solutions. As we highlight in this study, the crime and punishment approach is not feasibly implemented if the overall institutional environment is weak. Since countrywide overhaul of corruption through sweeping reform programs, the other reform approach, is a difficult and lengthy task, there is a need for an alternative kind of reform. In the case of a corruption-ridden centralised forest management regime, institutional reform should move away from enforcement of existing institutions and promote communal management of natural resources by locals

    Trade, Technique and Composition Effects: What is Behind the Fall in World-Wide SO2 Emissions 1990-2000?

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    Combining unique data bases on emissions with sectoral output and employment data, we study the sources of the fall in world-wide SO2 emissions and estimate the impact of trade on emissions. Contrarily to concerns raised by environmentalists, an emission-decomposition exercise shows that scale effects are dominated by technique effects working towards a reduction in emissions. A second exercise comparing the actual trade situation with an autarky benchmark estimates that trade, by allowing clean countries to become net importers of emissions, leads to a 10% increase in world emissions with respect to autarky in 1990, a figure that shrinks to 3.5% in 2000. Additionally, back-of-the-envelope calculations suggest that emissions related to transport are of the same magnitude. In a third exercise, we use linear programming to simulate extreme situations where world emissions are either maximal or minimal. It turns out that effective emissions correspond to a 90% reduction with respect to the worst case, but that another 80% reduction could be reached if emissions were minimal

    An Economic Model for Bioprospecting Contracts

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    This paper explores the use of a micro-economic model to analyse the provisions and parties of bioprospecting contracts. It focuses on the pharmaceutical industry as the representative biodiversity buyer, presenting an original theoretical framework that explains the main contract characteristics or stylised facts. Against this background, it considers the main contractors involved in these private contracts, i.e. biodiversity sellers and biodiversity buyers, analysing both the magnitude and distribution of the respective payoffs. Particular attention is devoted to the different, mixed impacts of bioprospecting contracts and patenting on social welfare. The positive welfare impacts delivered by bioprospecting contracts are associated with the potential discovery of a new drug product, i.e. productivity gains, non-monetary benefit-sharing or transfers and royalty revenues. The negative welfare impact results from the legal creation of a monopoly and the related well-known effect on the consumer surplus. Finally, the potential redistribution effects are limited, and a potential enforcement of this objective may jeopardise the desirability of the contracts since this action would lead to a significant increase in the transaction costs

    Uncertainty and the Double Dividend Hypothesis

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    This paper examines the double dividend hypothesis in the presence of labour income uncertainty. Empirical evidence shows that uncertainty over labour income is particularly significant in developing, while not negligible in developed countries. Under uncertainty, and assuming incomplete capital markets, the tax system plays a role in providing social insurance and a green tax reform influences its effectiveness. We show that the increase in environmental tax reduces consumption risk while the balanced budget decrease in labour income tax increases income risk. We find that the total welfare effect of a green tax reform differs substantially from the case of certainty. The critical parameters determining the existence of a second dividend are the lump sum transfers, the relative substitutability of the two goods for leisure and the initial tax rates relative to their optimal that determine also the response of labour supply to a change in the tax mix
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