771 research outputs found

    Cytotoxicity of the mycotoxins deoxynivalenol and ochratoxin A on Caco-2 cell line in presence of resveratrol

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    Exposure to mycotoxins through dietary food intake involves a highly complex scenario where co-contamination of different mycotoxins has been frequently demonstrated. On the other hand, the effect of the interaction of mycotoxins with other generally considered beneficial food components, as the antioxidants, has been scarcely studied. The main goal of the present work was to assess the cytotoxic effects on Caco-2 cells of the mycotoxins deoxynivalenol (DON) and ochratoxin A (OTA), alone or combined, and to explore potential protective effects of resveratrol (RES), an antioxidant frequently found in wine. In parallel, reactive oxygen species (ROS) production has also been studied as a first approach to understand the underlying mechanism of cytotoxicity. Results indicate a higher toxic effect of the mycotoxins when they are co-exposed. This increase in cytotoxicity was not accompanied by an increase in ROS production. The co-exposure of OTA or DON with RES did not result in a decrease in cytotoxicity; on the contrary, it resulted in increased cytotoxicity not associated with an increase in ROS production.The authors are grateful to the CYTED Action 109AC0371, to the INIA project (RTA 2012-00053-00-00) as well as the Spanish (Project AGL2011-24862) and Catalonian (XaRTA-Reference Network on Food Technology) Governments for their financial support. C.A. González-Arias thanks the Secretaria de Universitats i Recerca del Departament de Economia i Coneixement of the Generalitat de Catalunya for the pre-doctoral grant

    Cryo-EM structure of a helicase loading intermediate containing ORC-Cdc6-Cdt1-MCM2-7 bound to DNA

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    In eukaryotes, the Cdt1-bound replicative helicase core MCM2-7 is loaded onto DNA by the ORC-Cdc6 ATPase to form a prereplicative complex (pre-RC) with an MCM2-7 double hexamer encircling DNA. Using purified components in the presence of ATP-γS, we have captured in vitro an intermediate in pre-RC assembly that contains a complex between the ORC-Cdc6 and Cdt1-MCM2-7 heteroheptamers called the OCCM. Cryo-EM studies of this 14-subunit complex reveal that the two separate heptameric complexes are engaged extensively, with the ORC-Cdc6 N-terminal AAA+ domains latching onto the C-terminal AAA+ motor domains of the MCM2-7 hexamer. The conformation of ORC-Cdc6 undergoes a concerted change into a right-handed spiral with helical symmetry that is identical to that of the DNA double helix. The resulting ORC-Cdc6 helicase loader shows a notable structural similarity to the replication factor C clamp loader, suggesting a conserved mechanism of action

    Biosorption and Biomineralization of U(VI) by the Marine Bacterium Idiomarina loihiensis MAH1: Effect of Background Electrolyte and pH

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    The main goal of this study is to compare the effects of pH, uranium concentration, and background electrolyte (seawater and NaClO4 solution) on the speciation of uranium(VI) associated with the marine bacterium Idiomarina loihiensis MAH1. This was done at the molecular level using a multidisciplinary approach combining X-ray Absorption Spectroscopy (XAS), Time-Resolved Laser-Induced Fluorescence Spectroscopy (TRLFS), and High Resolution Transmission Electron Microscopy (HRTEM). We showed that the U(VI)/bacterium interaction mechanism is highly dependent upon pH but also the nature of the used background electrolyte played a role. At neutral conditions and a U concentration ranging from 5·10−4 to 10−5 M (environmentally relevant concentrations), XAS analysis revealed that uranyl phosphate mineral phases, structurally resembling meta-autunite [Ca(UO2)2(PO4)2 2–6H2O] are precipitated at the cell surfaces of the strain MAH1. The formation of this mineral phase is independent of the background solution but U(VI) luminescence lifetime analyses demonstrated that the U(VI) speciation in seawater samples is more intricate, i.e., different complexes were formed under natural conditions. At acidic conditions, pH 2, 3 and 4.3 ([U] = 5·10−4 M, background electrolyte = 0.1 M NaClO4), the removal of U from solution was due to biosorption to Extracellular Polysaccharides (EPS) and cell wall components as evident from TEM analysis. The LIII-edge XAS and TRLFS studies showed that the biosorption process observed is dependent of pH. The bacterial cell forms a complex with U through organic phosphate groups at pH 2 and via phosphate and carboxyl groups at pH 3 and 4.3, respectively. The differences in the complexes formed between uranium and bacteria on seawater compared to NaClO4 solution demonstrates that the actinide/microbe interactions are influenced by the three studied factors, i.e., the pH, the uranium concentration and the chemical composition of the solution.This work was funded by the grants CGL2009-09760 and CGL2012-36505 (Ministerio de Ciencia e Innovación), and RNM 3943 (Junta de Andalucía), Spain

    Specific Cell Targeting Therapy Bypasses Drug Resistance Mechanisms in African Trypanosomiasis

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    African trypanosomiasis is a deadly neglected disease caused by the extracellular parasite Trypanosoma brucei. Current therapies are characterized by high drug toxicity and increasing drug resistance mainly associated with loss-of-function mutations in the transporters involved in drug import. The introduction of new antiparasitic drugs into therapeutic use is a slow and expensive process. In contrast, specific targeting of existing drugs could represent a more rapid and cost-effective approach for neglected disease treatment, impacting through reduced systemic toxicity and circumventing resistance acquired through impaired compound uptake. We have generated nanoparticles of chitosan loaded with the trypanocidal drug pentamidine and coated by a single domain nanobody that specifically targets the surface of African trypanosomes. Once loaded into this nanocarrier, pentamidine enters trypanosomes through endocytosis instead of via classical cell surface transporters. The curative dose of pentamidine-loaded nanobody-chitosan nanoparticles was 100-fold lower than pentamidine alone in a murine model of acute African trypanosomiasis. Crucially, this new formulation displayed undiminished in vitro and in vivo activity against a trypanosome cell line resistant to pentamidine as a result of mutations in the surface transporter aquaglyceroporin 2. We conclude that this new drug delivery system increases drug efficacy and has the ability to overcome resistance to some anti-protozoal drugs.JAGS was funded by the European Union, grant FP7-HEALTH-2007-B-2.3.4-1.223048, NANOTRYP and Ministerio de Economía y Competitividad, Spain Plan Nacional de Investigación grant SAF2011- 30528. JLA was funded by Instituto de Salud Carlos III, Spain, grant FIS. 11/02571. HPdK was supported by a grant from the Medical Research Council (84733)

    Impact-parameter dependent nuclear parton distribution functions: EPS09s and EKS98s and their applications in nuclear hard processes

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    We determine the spatial (impact parameter) dependence of nuclear parton distribution functions (nPDFs) using the AA-dependence of the spatially independent (averaged) global fits EPS09 and EKS98. We work under the assumption that the spatial dependence can be formulated as a power series of the nuclear thickness functions TAT_A. To reproduce the AA-dependence over the entire xx range we need terms up to [TA]4[T_A]^4. As an outcome, we release two sets, EPS09s (LO, NLO, error sets) and EKS98s, of spatially dependent nPDFs for public use. We also discuss the implementation of these into the existing calculations. With our results, the centrality dependence of nuclear hard-process observables can be studied consistently with the globally fitted nPDFs for the first time. As an application, we first calculate the LO nuclear modification factor RAA1jetR^{1jet}_{AA} for primary partonic-jet production in different centrality classes in Au+Au collisions at RHIC and Pb+Pb collisions at LHC. Also the corresponding central-to-peripheral ratios RCP1jetR_{CP}^{1jet} are studied. We also calculate the LO and NLO nuclear modification factors for single inclusive neutral pion production, RdAuπ0R_{dAu}^{\pi^0}, at mid- and forward rapidities in different centrality classes in d+Au collisions at RHIC. In particular, we show that our results are compatible with the PHENIX mid-rapidity data within the overall normalization uncertainties given by the experiment. Finally, we show our predictions for the corresponding modifications RpPbπ0R_{pPb}^{\pi^0} in the forthcoming p+Pb collisions at LHC.Comment: 36 page

    Spain: Underwater Exploration on a Narrow Continental Shelf

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    In spite of Spain’s long coastline (nearly 8000 km) and its well-established tradition in underwater archaeology, the prehistoric settlement of the continental shelf is practically unknown with very few finds. Underwater research has focused on naval archaeology and, until very recently, no attempt had been made to look for prehistoric underwater sites. In the past decade,new research projects have been launched to explore selected areas on the Cantabrian shelf and offshore of Gibraltar. This chapter summarises the currently available evidence of submerged prehistoric archaeology and the preliminary results of these new project

    A computational analysis of the dynamic roles of talin, Dok1, and PIPKI for integrin activation

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    Integrin signaling regulates cell migration and plays a pivotal role in developmental processes and cancer metastasis. Integrin signaling has been studied extensively and much data is available on pathway components and interactions. Yet the data is fragmented and an integrated model is missing. We use a rule-based modeling approach to integrate available data and test biological hypotheses regarding the role of talin, Dok1 and PIPKI in integrin activation. The detailed biochemical characterization of integrin signaling provides us with measured values for most of the kinetics parameters. However, measurements are not fully accurate and the cellular concentrations of signaling proteins are largely unknown and expected to vary substantially across different cellular conditions. By sampling model behaviors over the physiologically realistic parameter range we find that the model exhibits only two different qualitative behaviours and these depend mainly on the relative protein concentrations, which offers a powerful point of control to the cell. Our study highlights the necessity to characterize model behavior not for a single parameter optimum, but to identify parameter sets that characterize different signaling modes

    Spatio-temporal distribution of pyrethroids in soil in Mediterranean paddy fields

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    [EN] The demand of rice by the increase in population in many countries has intensified the application of pesticides and the use of poor quality water to irrigate fields. The terrestrial environment is one compartment affected by these situations, where soil is working as a reservoir, retaining organic pollutants. Therefore, it is necessary to develop methods to determine insecticides in soil and monitor susceptible areas to be contaminated, applying adequate techniques to remediate them. Materials and methods This study investigates the occurrence of ten pyrethroid insecticides (PYs) and its spatio-temporal variance in soil at two different depths collected in two periods (before plow and during rice production), in a paddy field area located in the Mediterranean coast. Pyrethroids were quantified using gas chromatography mass spectrometry (GC MS) after ultrasound-assisted extraction with ethyl acetate. The results obtained were assessed statistically using non-parametric methods, and significant statistical differences (p&#8201;<&#8201;0.05) in pyrethroids content with soil depth and proximity to wastewater treatment plants were evaluated. Moreover, a geographic information system (GIS) was used to monitor the occurrence of PYs in paddy fields and detect risk areas. Results and discussion Pyrethroids were detected at concentrations &#8804;57.0 ng g&#8722;1 before plow and &#8804;62.3 ng g&#8722;1 during rice production, being resmethrin and cyfluthrin the compounds found at higher concentrations in soil. Pyrethroids were detected mainly at the top soil, and a GIS program was used to depict the obtained results, showing that effluents from wastewater treatment plants (WWTPs) were the main sources of soil contamination. No toxic effects were expected to soil organisms, but it is of concern that PYs may affect aquatic organisms, which represents the worst case scenario. Conclusions A methodology to determine pyrethroids in soil was developed to monitor a paddy field area. The use of water from WWTPs to irrigate rice fields is one of the main pollution sources of pyrethroids. It is a matter of concern that PYs may present toxic effects on aquatic organisms, as they can be desorbed from soil. Phytoremediation may play an important role in this area, reducing the possible risk associated to PYs levels in soil.Authors wish to thank INIA for the predoctoral fellowship (R. Aznar) and Spanish Ministry of Economy and Competitiveness RTA2014-00012-C03-01 for financial support and Jonathan Villanueva Martin for his contribution to this work.Aznar, R.; Moreno-Ramón, H.; Albero, B.; Sánchez Brunete, C.; Tadeo, JL. (2016). Spatio-temporal distribution of pyrethroids in soil in Mediterranean paddy fields. Journal of Soils and Sediments. 17(5):1503-1513. https://doi.org/10.1007/s11368-016-1417-2S15031513175Albaseer SS, Rao RN, Swamy YV, Mukkanti K (2010) An overview of sample preparation and extraction of synthetic pyrethroids from water, sediment and soil. J Chromatogr A 1217(35):5537–5554Alonso MB, Feo ML, Corcellas C, Vidal LG, Bertozzi CP, Marigo J, Secchi ER, Bassoi M, Azevedo AF, Dorneles PR, Torres JPM, Lailson-Brito J, Malm O, Eljarrat E, Barcelo D (2012) Pyrethroids: a new threat to marine mammals? Environ Int 47:99–106Amweg EL, Weston DP, Ureda NM (2005) Use and toxicity of pyrethroid pesticides in the Central Valley, California, USA. Environ Toxicol Chem 24(4):966–972Arias-Estevez M, Lopez-Periago E, Martinez-Carballo E, Simal-Gandara J, Mejuto JC, Garcia-Rio L (2008) The mobility and degradation of pesticides in soils and the pollution of groundwater resources. Agric Eco Environ 123(4):247–260Aznar R, Albero B, Sanchez-Brunete C, Miguel E, Tadeo JL (2014) Multiresidue analysis of insecticides and other selected environmental contaminants in poultry manure by gas chromatography/mass spectrometry. J AOAC Int 97(4):978–986Campo J, Masia A, Blasco C, Pico Y (2013) Occurrence and removal efficiency of pesticides in sewage treatment plants of four Mediterranean River Basins. J Hazard Mater 263:146–157European Commission (2002) Review report for the active substance Cyfluthrin, 6843/VI/97-finalEuropean Commission (2004) Review report for the active substance α-Cypermethrin, SANCO/4335/2000-finalEuropean Commission (2005) Review report for the active substance Esfenvalerate, 6846/VI/97-finalFeo ML, Ginebreda A, Eljarrat E, Barcelo D (2010) Presence of pyrethroid pesticides in water and sediments of Ebro River Delta. J Hydrol 393(3-4):156–162Fojut TL, Palumbo AJ, Tjeerdema RS (2012) Aquatic life water quality criteria derived via the UC Davis method: II. Pyrethroid insecticides. Rev Environ Contam Toxicol 216:51–103Gan J, Lee SJ, Liu WP, Haver DL, KAbashima JN (2005) Distribution and persistence of pyrethroids in runoff sediments. J Environ Qual 34:836–841Hill IR (1985) Aquatic organisms and pyrethroids. Pestic Sci 27:429–465Huang LM, Thompson A, Zhang GL, Chen LM, Han GZ, Gong ZT (2015) The use of chronosequences in studies of paddy soil evolution: a review. Geoderma 237:199–210Katagi T (2004) Photodegradation of pesticides on plant and soil surfaces. Rev Environ Contam Toxicol 182:1–189Laskowski DA (2002) Physical and chemical properties of pyrethroids. Rev Environ Contam Toxicol 174:49–170Mahabali S, Spagnoghe P (2014) Mitigation of two insecticides by wetlands plants: feasibility study for the treatment of agricultural runoff in Suriname (South America). Water Air Soil Pollut 225:1771Maund SJ, Hamer MJ, Lane MCG, Farrelly E, Rapley JH, Goggin UM, Gentle WE (2002) Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environ Toxicol Chem 21(1):9–15Maund SJ, Campbell PJ, Giddings JM, Hamer MJ, Henry K, Pilling ED, Warinton JS, Wheeler JR (2012) Ecotoxicology of synthetic pyrethroids. Top Curr Chem 314:137–165Money E, Carter GP, Serre ML (2009) Using river distances in the space/time estimation of dissolved oxygen along two impaired river networks in New Jersey. Water Res 43(7):1948–1958Moore MT, Cooper CM, Smith S, Jr Cullum RF, Knight SS, Locke MA, Bennett ER (2009) Mitigation of two pyrethroid insecticides in Mississippi Delta constructed wetland. Environ Pollut 157:250–256Moreno-Ramón H, Marqués-Mateu A, Ibáñez-Asensio S, Gisbert JM (2015) Wetland soils under rice management and seawater intrusion: characterization and classification. Spa J Soil Sci 5(2):111–129Nawaz MF, Bourrie G, Trolard F, Mouret JC, Henry P (2013) Effects of agronomic practices on the physico-chemical properties of soil waters in rice culture. Turk J Agric For 37(2):195–202Oros DR, Werner I (2005) Pyrethroid insecticides: an analysis of use patterns, distributions, potential toxicity and fate in the Sacramento-San Joaquin Delta and Central Valley. White Paper for the Interagency Ecological Program. SFEI Contribution 415. San Francisco Estuary Institute, Oakland, CAPascual-Aguilar J, Andreu V, Gimeno-Garcia E, Pico Y (2015) Current anthropogenic pressures on agro-ecological protected coastal wetlands. Sci Total Environ 03:190–199Soil Survey Staff (2014a) Soil survey field and laboratory methods manual. Soil survey investigations report no. 51, version 2.0. In: Burt R, Soil Survey Staff (eds). U.S. Department of Agriculture, Natural Resources Conservation Service, Washington, p 407Soil Survey Staff (ed) (2014b) Keys to soil taxonomy, 12th edn. USDA-Natural Resources Conservation Service, Washington, p 372Song Y, Kai J, Song X, Zhang W, Li L (2015) Long-term toxic effects of deltamethrin and fenvalerate in soil. J Hazard Mater 289:158–164Weston DP, Holmes RW, You J, Lydy MJ (2005) Aquatic toxicity due to residential use of pyrethroid insecticides. Environ Sci Technol 39(24):9778–9784Weston DP, Ramil HL, Lydy MJ (2013) Pyrethroid insecticides in municipal wastewater. Environ Toxicol Chem 32(11):2460–2468Zhou JL, Rowland S, Mantoura RFC (1995) Partition of synthetic pyrethroid insecticides between dissolved and particulate phases. Water Res 29:1023–110

    Ethnobotanical remarks on Central and Southern Italy

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    <p>Abstract</p> <p>Background</p> <p>The present paper is a brief survey on the ethnobotanical works published by the Authors since 1981, concerning the research carried out in some southern and central Italian regions. Before Roman domination these territories were first inhabited by local people, while the southern areas were colonized by the Greeks. These different cultural contributions left certain traces, both in the toponyms and in the vernacular names of the plants and, more generally, in the culture as a whole.</p> <p>Methods</p> <p>Field data were collected through open interviews, mainly of farmers, shepherds and elderly people, born or living in these areas for a long time. Voucher specimens of collected plants are preserved in the respective herbaria of the Authors and in the herbarium of "Roma Tre" University. Important contributions have been made by several students native to the areas under consideration. A comparative analysis with local specific ethnobotanical literature was carried out.</p> <p>Results</p> <p>The paper reports several examples concerning human and veterinary popular medicine and in addition some anti-parasitic, nutraceutic, dye and miscellaneous uses are also described. Moreover vernacular names and toponyms are cited. Eight regions of central and southern Italy (particularly Latium, Abruzzo, Marche and Basilicata) were investigated and the data obtained are presented in 32 papers. Most of the species of ethnobotanical interest have been listed in Latium (368 species), Marche (274) and Abruzzo (203). The paper also highlights particularly interesting aspects or uses not previously described in the specific ethnobotanical literature.</p> <p>Conclusion</p> <p>Phyto-therapy in central and southern Italy is nowadays practised by a few elderly people who resort to medicinal plants only for mild complaints (on the contrary food uses are still commonly practised). Nowadays therapeutic uses, unlike in the past, are less closely or not at all linked to ritual aspects. Several plants deserve to be taken into consideration not only from the anthropological or cultural point of view, but also for further phyto-chemical investigation. Our studies, as well as those of other authors, try to provide an original picture of the local ethno-biodiversity.</p
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