488 research outputs found

    Inhibition of nitric oxide biosynthesis by anthocyanin fraction of blackberry extract.

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    Anthocyanins are natural colorant belonging to the flavonoid family, widely distributed among flowers, fruits, and vegetables. Some flavonoids have been found to possess anticarcinogenic, cytotoxic, cytostatic, antioxidant, and anti-inflammatory properties. Since increased nitric oxide (NO) plays a role in inflammation, we have investigated whether the pharmacological activity of the anthocyanin fraction of a blackberry extract (cyanidin-3-O-glucoside representing about 88% of the total anthocyanin content) was due to the suppression of NO synthesis. The markedly increased production of nitrites by stimulation of J774 cells with lipopolysaccharide (LPS) for 24 h was concentration-dependently inhibited by the anthocyanin fraction (11, 22, 45, and 90 μg/ml) of the extract. Moreover, this inhibition was dependent on a dual mechanism, since the extract attenuated iNOS protein expression and decreased the iNOS activity in lungs from LPS-stimulated rats. Inhibition of iNOS protein expression appeared to be at the transcriptional level, since the extract and similarly cyanidin-3-O-glucoside (10, 20, 40, and 80 μg/ml, amounts corresponding to the concentrations present in the extract) decreased LPS-induced NF-κB activation, through inhibition of IκBα degradation, and reduced ERK-1/2 phosphorylation in a concentration-dependent manner. In conclusion, our study demonstrates that at least some part of the anti-inflammatory activity of blackberry extract is due to the suppression of NO production by cyanidin-3-O-glucoside, which is the main anthocyanin present in the extract. The mechanism of this inhibition seems to be due to an action on the expression/activity of the enzyme. In particular, the protein expression was inhibited through the attenuation of NF-κB and/or MAPK activatio

    Preface: Earth Observation for Integrated Water and Basin Management: Challenges for adaptation to a changing environment

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    Integrated river basin management involves a sound knowledge of water and land interactions, and impacts from and feedbacks to human activity. Remote sensing has been an efficient and increasingly promising means of gathering direct information of the Earth surface, as well as information on water and energy fluxes. The recent generation of high-resolution sensors offers a huge potential for monitoring, assessing, and modelling our changing environment in a context of uncertainty about how future climate conditions will affect the current water resource and basin management framework. Moreover, large amounts of data are now available posing a challenging opportunity to the scientific community for both exploring and transforming these data into readily usable information products for different end-users in our societies

    PROTECTIVE EFFECTS OF ANTHOCYANINS FROM BLACKBERRY IN A RAT MODEL OF ACUTE LUNG INFLAMMATION.

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    Anthocyanins are a group of naturally occuring phenolic compounds related to the coloring of plants, flowers and fruits. These pigments are important as quality indicators, as chemotaxonomic markers and for their antioxidant activities. Here, we have investigated the therapeutic efficacy of anthocyanins contained in blackberry extract (cyanidin-3-O-glucoside represents about 80% of the total anthocyanin contents) in an experimental model of lung inflammation induced by carrageenan in rats. Injection of carrageenan into the pleural cavity elicited an acute inflammatory response characterized by fluid accumulation which contained a large number of neutrophils as well as an infiltration of polymorphonuclear leukocytes in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NOx) and prostaglandin E2 (PGE2). All parameters of inflammation were attenuated in a dose-dependent manner by anthocyanins (10, 30 mg kg-1 30 min before carrageenan). Furthermore, carrageenan induced an upregulation of the adhesion molecule ICAM-1, nitrotyrosine and poly (ADP-ribose) synthetase (PARS) as determined by immunohistochemical analysis of lung tissues. The degree of staining was lowered by anthocyanins treatment. Thus, the anthocyanins contained in the blackberry extract exert multiple protective effects in carrageenan-induced pleurisy

    Modeling Surface Energy Fluxes over a Dehesa (Oak Savanna) Ecosystem Using a Thermal Based Two-Source Energy Balance Model (TSEB) I

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    Savannas are among the most variable, complex and extensive biomes on Earth, supporting livestock and rural livelihoods. These water-limited ecosystems are highly sensitive to changes in both climatic conditions, and land-use/management practices. The integration of Earth Observation (EO) data into process-based land models enables monitoring ecosystems status, improving its management and conservation. In this paper, the use of the Two-Source Energy Balance (TSEB) model for estimating surface energy fluxes is evaluated over a Mediterranean oak savanna (dehesa). A detailed analysis of TSEB formulation is conducted, evaluating how the vegetation architecture (multiple layers) affects the roughness parameters and wind profile, as well as the reliability of EO data to estimate the ecosystem parameters. The results suggest that the assumption of a constant oak leaf area index is acceptable for the purposes of the study and the use of spectral information to derive vegetation indices is sufficiently accurate, although green fraction index may not reflect phenological conditions during the dry period. Although the hypothesis for a separate wind speed extinction coefficient for each layer is partially addressed, the results show that taking a single oak coefficient is more precise than using bulk system coefficient. The accuracy of energy flux estimations, with an adjusted Priestley–Taylor coefficient (0.9) reflecting the conservative water-use tendencies of this semiarid vegetation and a roughness length formulation which integrates tree structure and the low fractional cover, is considered adequate for monitoring the ecosystem water use (RMSD ~40W m-2)

    Long-Term water stress and drought assessment of Mediterranean oak savanna vegetation using thermal remote sensing

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    Drought is a devastating natural hazard that is difficult to define, detect and quantify. The increased availability of both meteorological and remotely sensed data provides an opportunity to develop new methods to identify drought conditions and characterize how drought changes over space and time. In this paper, we applied the surface energy balance model, SEBS (Surface Energy Balance System), for the period 2001 2018, to estimate evapotranspiration and other energy fluxes over the dehesa area of the Iberian Peninsula, with a monthly temporal resolution and 0.05° pixel size. A satisfactory agreement was found between the fluxes modeled and the measurements obtained for 3 years by two flux towers located over representative sites (RMSD = 21 W m-2 and R2 = 0.76, on average, for all energy fluxes and both sites). The estimations of the convective fluxes (LE and H) showed higher deviations, with RMSD = 26 W m-2 on average, than Rn and G, with RMSD = 15 W m-2. At both sites, annual evapotranspiration (ET) was very close to total precipitation, with the exception of a few wet years in which intense precipitation events that produced high runoff were observed. The analysis of the anomalies of the ratio of ET to reference ET (ETo) was used as an indicator of agricultural drought on monthly and annual scales. The hydrological years 2004/2005 and 2011/2012 stood out for their negative values. The first one was the most severe of the series, with the highest impact observed on vegetation coverage and grain production. On a monthly scale, this event was also the longest and most intense, with peak negative values in January February and April May 2005, explaining its great impact on cereal production (up to 45 % reduction). During the drier events, the changes in the grasslands and oak trees ground cover allowed for a separate analysis of the strategies adopted by the two strata to cope with water stress. These results indicate that the drought events characterized for the period did not cause any permanent damage to the vegetation of dehesa systems. The approach tested has proven useful for providing insight into the characteristics of drought events over this ecosystem and will be helpful to identify areas of interest for future studies at finer resolutions

    Remote sensing of water use and water stress in the African savanna ecosystem at local scale – Development and validation of a monitoring tool

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    Savannas are among the most productive biomes of Africa, where they comprise half of its surface. They support wildlife, livestock, rangelands, crops, and livelihoods, playing an important socioeconomic role in rural areas. These water-limited ecosystems with seasonal water availability are highly sensitive to changes in both climate conditions, and in land-use/management practices. Although monitoring programs for African savanna water use have been established in certain areas, most of them are largely restricted to point based measurements or coarse scales, and are not fully capable to provide distributed timely information for planning purposes. In this study we develop a mechanism for monitoring the water used by African savanna from fine scale (meters) to watershed scale, integrating the effects of the water stress. Our hypothesis is that the Ecosystem Stress Index (ESI) is a valuable tool to downscale estimates of actual evapotranspiration at coarse scale, to high resolutions. To monitor savanna water fluxes in a semi-continuous way this study integrates two different ET-estimation approaches: KC-FAO56 model, integrating reflectance-based “crop” coefficients (SPOT 4 & 5 satellites), is used to derive unstressed savanna evapotranspiration (with high spatial resolution), and the two-source surface energy balance model -TSEB, integrating radiometric surface temperature (AATSR satellites) allows the determination of water stress across savannas (ESI, with low spatial resolution). The difference between estimated and observed surface fluxes derived from TSEB (RMSDLE = 53 Wm-2, RMSDH = 50 Wm-2, RMSDRn = 60 Wm-2, RMSDG = 21 Wm-2) were of the same magnitude as the uncertainties derived from the flux measurement system, being sufficiently accurate to be employed in a distributed way and on a more regular basis. The approach of ESI to downscale ET proved to be useful, and errors between estimated and observed daily ET (RMSD 0.6 mmday−1) were consistent with the results of other studies in savanna ecosystems. The modelling framework proposed provided an accurate representation of the natural landscape heterogeneity and local conditions, with the potential of providing information suitable from local to broader scales.info:eu-repo/semantics/publishedVersio

    Exploring TanDEM-X Interferometric Products for Crop-Type Mapping

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    The application of satellite single-pass interferometric data to crop-type mapping is demonstrated for the first time in this work. A set of nine TanDEM-X dual-pol pairs of images acquired during its science phase, from June to August 2015, is exploited for this purpose. An agricultural site located in Sevilla (Spain), composed of fields of 13 different crop species, is employed for validation. Sets of input features formed by polarimetric and interferometric observables are tested for crop classification, including single-pass coherence and repeat-pass coherence formed by consecutive images. The backscattering coefficient at HH and VV channels and the correlation between channels form the set of polarimetric features employed as a reference set upon which the added value of interferometric coherence is evaluated. The inclusion of single-pass coherence as feature improves by 2% the overall accuracy (OA) with respect to the reference case, reaching 92%. More importantly, in single-pol configurations OA increases by 10% for the HH channel and by 8% for the VV channel, reaching 87% and 88%, respectively. Repeat-pass coherence also improves the classification performance, but with final scores slightly worse than with single-pass coherence. However, it improves the individual performance of the backscattering coefficient by 6–7%. Furthermore, in products evaluated at field level the dual-pol repeat-pass coherence features provide the same score as single-pass coherence features (overall accuracy above 94%). Consequently, the contribution of interferometry, both single-pass and repeat-pass, to crop-type mapping is proved.This work was funded by the Spanish Ministry of Science and Innovation, the State Agency of Research (AEI) and the European Funds for Regional Development (EFRD) under Project TEC2017-85244-C2-1-P, and by the European Commission, H2020 Programme, under Project MOSES (Managing crOp water Saving with Enterprise Services)

    Preface: Earth Observation for Integrated Water and Basin Management: Challenges for adaptation to a changing environment

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    Integrated river basin management involves a sound knowledge of water and land interactions, and impacts from and feedbacks to human activity. Remote sensing has been an efficient and increasingly promising means of gathering direct information of the Earth surface, as well as information on water and energy fluxes. The recent generation of high-resolution sensors offers a huge potential for monitoring, assessing, and modelling our changing environment in a context of uncertainty about how future climate conditions will affect the current water resource and basin management framework. Moreover, large amounts of data are now available posing a challenging opportunity to the scientific community for both exploring and transforming these data into readily usable information products for different end-users in our societies

    SPARC regulation of PMN clearance protects from pristane-induced lupus and rheumatoid arthritis

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    The secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein with unexpected immunosuppressive function in myeloid cells. We investigated the role of SPARC in autoimmunity using the pristane-induced model of lupus that, in mice, mimics human systemic lupus erythematosus (SLE). Sparc−/− mice developed earlier and more severe renal disease, multi-organ parenchymal damage, and arthritis than the wild-type counterpart. Sparc+/- heterozygous mice showed an intermediate phenotype suggesting Sparc gene dosage in autoimmune-related events. Mechanistically, reduced Sparc expression in neutrophils blocks their clearance by macrophages, through defective delivery of don't-eat-me signals. Dying Sparc−/− neutrophils that escape macrophage scavenging become source of autoantigens for dendritic cell presentation and are a direct stimulation for γδT cells. Gene profile analysis of knee synovial biopsies from SLE-associated arthritis showed an inverse correlation between SPARC and key autoimmune genes. These results point to SPARC down-regulation as a leading event characterizing SLE and rheumatoid arthritis pathogenesis
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