2,476 research outputs found

    Exploiting cell cycle inhibitor genes of the KRP family to control root-knot nematode induced feeding sites in plants.

    Get PDF
    Made available in DSpace on 2018-08-11T00:42:06Z (GMT). No. of bitstreams: 1 Coelhoetal2017PlantCellampEnvironment.pdf: 5492267 bytes, checksum: 547162c264fe8e6c301bf52439d7d29d (MD5) Previous issue date: 2017-08-11bitstream/item/162650/1/Coelho-et-al-2017-Plant-Cell-amp-Environment.pd

    The influence of seasonality on the content of goyazensolide and on anti-inflammatory and anti-hyperuricemic effects of the ethanolic extract of Lychnophora passerina (Brazilian arnica).

    Get PDF
    Ethnopharmacological relevance: Lychnophora passerina (Mart ex DC) Gardn (Asteraceae), popularly known as Brazilian arnica, is used in Brazilian folk medicine to treat pain, rheumatism, bruises, inflammatory diseases and insect bites. Aim of the study: Investigate the influence of the seasons on the anti-inflammatory and anti-hyperuricemic activities of ethanolic extract of L. passerina and the ratio of the goyazensolide content, main chemical constituent of the ethanolic extract, with these activities. Materials and methods: Ethanolic extracts of aerial parts of L. passerina were obtained from seasons: summer (ES), autumn (EA), winter (EW) and spring (EP). The sesquiterpene lactone goyazensolide, major metabolite, was quantified in ES, EA, EW and EP by a developed and validated HPLC-DAD method. The in vivo antihyperuricemic and anti-inflammatory effects of the ethanolic extracts from L. passerina and goyazensolide were assayed on experimental model of oxonate-induced hyperuricemia in mice, liver xanthine oxidase (XOD) inhibition and on carrageenan-induced paw edema in mice. Results: HPLC method using aqueous solution of acetic acid 0.01% (v/v) and acetonitrile with acetic acid 0.01% (v/v) as a mobile phase in a gradient system, with coumarin as an internal standard and DAD detection at 270 nm was developed. The validation parameters showed linearity in a range within 10.0?150.0 ?g/ml, with intraday and interday precisions a range of 0.61?3.82. The accuracy values of intraday and interday analysis within 87.58? 100.95%. EA showed the highest goyazensolide content. From the third to the sixth hour after injection of carrageenan, treatments with all extracts at the dose of 125 mg/kg were able to reduce edema. Goyazensolide (10 mg/kg) showed significant reduction of paw swelling from the second hour assay. This sesquiterpene lactone was more active than extracts and presented similar effect to indomethacin. Treatments with ES, EA and EP (125 mg/kg) and goyazensolide (10 mg/kg) reduced serum urate levels compared to hyperuricemic control group and were able to inhibit liver XOD activity. One of the mechanisms by which ES, EA, EP and goyazensolide exercise their anti-hyperuricemic effect is by the inhibition of liver XOD activity. Goyazensolide was identified as the main compound present in ES, EA, EW and EP and it is shown to be one of the chemical constituents responsible for the anti-inflammatory and anti-hyperuricemic effects of the ethanolic extracts. Conclusion: The anti-inflammatory and anti-hyperuricemic activities of the ethanolic extracts from L. passerina were not proportionally influenced by the variation of goyazensolide content throughout the seasons. The involvement of goyazensolide on in vivo anti-inflammatory and anti-hyperuricemic activities of L. passerina extracts was confirmed, as well as the possibility of participation of other constituents on these effects. This study demonstrated that the aerial parts of L. passerina may be collected in any season for use as anti-inflammatory agent. For use in hyperuricemia, the best seasons for the collection are summer, autumn and spring. The ethanolic extract of L. passerina and goyazensolide can be considered promising agents in the therapeutic of inflammation, hyperuricemia and gout

    Purification of a lectin with antibacterial activity from Bothrops leucurus snake venom

    Get PDF
    A novel lectin was isolated from Bothrops leucurus snake venom using a combination of affinity and gel filtration chromatographies. the lectin (BIL) agglutinated glutaraldehyde-treated rabbit and human erythrocytes with preference for rabbit erythrocytes. Galactose, raffinose, lactose, fetal bovine serum and casein inhibited lectin-induced rabbit erythrocyte agglutination. BIL, with a molecular mass of 30 kDa and composed of two subunits of 15 kDa, showed dependence on calcium. BIL is an acidic protein with highest activity over the pH range of 4.0-7.0 and stable under heating to 70 degrees C. Fluorescence emission spectra showed tryptophan residues partially buried within the lectin structure. the percentages of secondary structure revealed by circular dichroism were 1% alpha-helix, 44% beta-sheet, 24% beta-turn and 31% unordered. BIL showed effective antibacterial activity against Gram-positive bacteria Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis with minimal inhibitory concentrations of 31.25, 62.25 and 125 mu g/mL, respectively. in conclusion, B. leucurus snake venom contains a galactoside-binding lectin with antibacterial activity. (C) 2011 Elsevier Inc. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Fed Pernambuco, Dept Bioquim, BR-50670420 Recife, PE, BrazilUniv Fed Bahia, Dept Zool, BR-40170210 Salvador, BA, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniv Fed Pernambuco, Dept Zool, BR-50670420 Recife, PE, BrazilUniv Estadual Oeste Parana, Ctr Engn & Ciencias Exatas, BR-85903000 Toledo, Parana, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilWeb of Scienc

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

    Get PDF
    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
    corecore