286 research outputs found

    Elastase-2, a tissue alternative pathway for angiotensin II generation, plays a role in circulatory sympathovagal balance in mice

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    In vitro and ex vivo experiments indicate that elastase-2 (ELA-2), a chymotrypsin-serine protease elastase family member 2A, is an alternative pathway for angiotensin II (Ang II) generation. However, the role played by ELA-2 in vivo is unclear. We examined ELA-2 knockout (ELA-2KO) mice compared to wild-type (WT) mice and determined whether ELA-2 played a role in hemodynamics [arterial pressure (AP) and heart rate (HR)], cardiocirculatory sympathovagal balance and baroreflex sensitivity. The variability of systolic arterial pressure (SAP) and pulse interval (PI) for evaluating autonomic modulation was examined for time and frequency domains (spectral analysis), whereas a symbolic analysis was also used to evaluate PI variability. In addition, baroreflex sensitivity was examined using the sequence method. Cardiac function was evaluated echocardiographically under anesthesia. The AP was normal whereas the HR was reduced in ELA-2KO mice (425 ± 17 vs. 512 ± 13 bpm from WT). SAP variability and baroreflex sensitivity were similar in both strains. The LF power from the PI spectrum (33.6 ± 5 vs. 51.8 ± 4.8 nu from WT) and the LF/HF ratio (0.60 ± 0.1 vs. 1.45 ± 0.3 from WT) were reduced, whereas the HF power was increased (66.4 ± 5 vs. 48.2 ± 4.8 nu from WT) in ELA-2KO mice, indicating a shift toward parasympathetic modulation of HR. Echocardiographic examination showed normal fractional shortening and an ejection fraction in ELA-2KO mice; however, the cardiac output, stroke volume, and ventricular size were reduced. These findings provide the first evidence that ELA-2 acts on the sympathovagal balance of the heart, as expressed by the reduced sympathetic modulation of HR in ELA-2KO mice

    Byrsonima Crassa Niedenzu (ik): Antimicrobial Activity And Chemical Study

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    The methanolic extract of leaves from Byrsonima crassa, a Brazilian medicinal plant, was analyzed by CC and HPLC. Four constituents were isolated and identified as quercetin, methyl gallate, (-)-epigallocatechin gallate and quercetin-3-O-(2″-galloyl)-α-L-arabinopyranoside. The methanolic and hydromethanolic extract, as well as fractions, were evaluated regarding their possible antimicrobial activity using in vitro methods. Results showed that both extracts and fractions exhibited significant antimicrobial activity against all tested strains.2617175Agrawal, P.K., (1989) Carbon 13NMR of Flavonoids, , Amsterdam:ElsevierAlzoreky, N.S., Nakahara, K., Antibacterial activity of extracts from some edible plants commonly consumed in Asia (2003) Int J Food Microbiol, 80, pp. 223-230Amarqiuise, A., Che, C.T., Bejar, E., Malone, M.H., Fong, H.H.S., A New Glycolipid from Byrsonima crassifolia (1994) Planta Med, 60, pp. 85-86Basile, A., Sorbo, S., Giordano, S., Ricciardi, L., Ferrara, S., Montesano, D., Cobianchi, R.C., Ferrara, L., Antibacterial and allelopathic activity of extract from Castanea sativa leaves (2000) Fitoterapia, 71, pp. S110-S116Bauer, A.W., Kirby, M.D.K., Sherries, J.C., Truck, M., Antibiotic susceptibilities testing by standard single disc diffusion method (1966) Am J Clin Pathol, 45, pp. 493-496Bejar, E., Amarquaye, A., Che, C.T., Malone, M.H., Fong, H.H.S., Constituents of Byrsonima crassifolia and their spasmogenic activity (1995) Int J Pharmacog, 33, pp. 25-32Binutu, O.A., Cordell, G.A., Gallic acid derivatives from Mezoneuron benthamianum leaves (2000) Pharm Biol, 38, pp. 284-286Djipa, C.D., Delmee, M., Quetin-Leclercq, J., Antimicrobial activity of bark extracts of Syzygium jambos (L.) Alston (Myrtaceae) (2000) J Ethnopharmacol, 71, pp. 307-313Geiss, F., Heinrich, M., Hunkler, D., Rimpler, H., Heinrich, M., Proanthocyanidins with (+)-epicatechin units from Byrsonima crassifolia bark (1995) Phytochemistry, 39, pp. 635-643Gottlieb, O.R., Henriques Mendes, P., Taveira Magalhães, M., Triterpenoids from Byrsonima verbascifolia (1975) Phytochemistry, 14, pp. 1456-1456Harborne, J.B., (1996) The Flavonoids: Advances in Research since 1986, , New York:Chapman & HallLopez, A., Hudson, J.B., Towers, G.H.N., Antiviral and antimicrobial activities of Colombian medicinal plants (2001) J Ethnopharmacol, 77, pp. 189-196Martínez-Vasquéz, M., González-Esquinca, A.R., Cazares Luna, L., Moreno Gutiérrez, M.N., García-Argáez, A.N., Antimicrobial activity of Byrsonima crassifolia (L.) H.B.K (1999) J Ethnopharmacol, 66, pp. 79-82Mendes, C.C., Cruz, F.G., David, J.M., Nascimento, I.P., David, J.P., Triterpenes esterified with fatty acid and triterpene acids isolated from Byrsonima microphylla (1999) Quím Nova, 22, pp. 185-188Nascimento, G.G.F., Locatelli, J., Freitas, P.C., Silva, G.L., Antibacterial activity of plants extracts and phytochemicals on antibiotic-resistant bacteria (2000) Braz J Microbiol, 31, pp. 247-256(2003) Performance Standards for Antimicrobial Disc Susceptibility Tests, , Approved Standard M2-A7, Pennsylvania:WaynePenna, C., Marino, S., Vivot, E., Cruanes, M.C., Munoz, J.D., Cruanes, J., Ferraro, G., Martino, V., Antimicrobial activity of Argentine plants used in the treatment of infectious diseases. Isolation of active compounds from Sebastiania brasiliensis (2001) J Ethnopharmacol, 77, pp. 37-40Pretorius, J.C., Magama, S., Zietsman, P.C., Purification and identification of antibacterial compounds from Euclea crispa subsp crispa (Ebenaceae) leaves (2003) S Afr J Bot, 69, pp. 579-586Rastrelli, L., De Tommasi, N., Berger, I., Caceres, A., Saravia, A., De Simone, F., Glycolipids from Byrsonima crassifolia (1997) Phytochemistry, 45, pp. 647-650Sannomiya, M., Rodrigues, C.M., Coelho, R.G., Santos, L.C., Hiruma-Lima, C.A., Souza Brito, A.R.M., Vilegas, W., Application of preparative high-speed counter-current chromatography for the separation of flavonoids from the leaves of Byrsonima crassa Niedenzu (IK) (2004) J Chromatogr A, 1035, pp. 47-51Sannomiya, M., Fonseca, V.B., Da Silva, M.A., Rocha, L.R.M., Dos Santos, L.C., Souza, H.C.A., Brito, A.R.M., Vilegas, W., Flavonoids and antiulcerogenic activity from Byrsonima crassa leaves extracts (2005) J Ethnopharmacol, 97, pp. 1-6Silva, S.R., Silva, A.P., Munhoz, C.B., Silva Jr., M.C., Medeiros, M.B., (2001) Guia de Plantas Do Cerrado Utilizadas Na Chapada Dos Veadeiros, , Brasília:WWF58pSrinivasan, D., Nathan, S., Suresh, T., Perumalsamy, P.L., Antimicrobial activity of certain Indian medicinal plants used in folkloric medicine (2001) J Ethnopharmacol, 74, pp. 217-220Wagner, H., Bladt, H., Zgainski, E.M., (1984) Plant Drug Analysis, , Berlin:Springer320

    Validation of microbiological assay for determination of cefuroxime in injectable preparations

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    The validation of a microbiological assay, applying agar diffusion method for determination of the active of cefuroxime in power for injection, is described. Using a strain of Micrococcus luteus ATCC 9341 as the test organism, cefuroxime was measured in concentrations ranging from 30.0 to 120.0 μg/mL. The method validation showed that it is linear (r = 0.9999), precise (relative standard deviation = 0.37 %) and accurate (it measured the added quantities). Microbiological assay is satisfactory for quantitation of cefuroxime in powder for injection and the validity of the proposed bioassay, which is a simple and a useful alternative methodology for cefuroxime determination in routine quality control.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    How gamma-rays and electron-beam irradiation would affect the antimicrobial activity of differently processed wild mushroom extracts?

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    Aims: The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial activity of mushroom species (Boletus edulis, Hydnum repandum, Macrolepiota procera and Russula delica) differently processed (fresh, dried, freeze) were evaluated. Methods and Results: Clinical isolates with different resistance profiles from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal, were used as target micro-organisms. The mushrooms antimicrobial activity did not suffer significant changes that might compromise applying irradiation as a possible mushroom conservation technology. Conclusions: Two kGy dose (independently of using gamma-rays or electron-beams) seemed to be the most suitable choice to irradiate mushrooms. Significance and Impact of the Study: This study provides important results in antimicrobial activity of extracts prepared from irradiated mushroom species.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and COMPETE/QREN/EU for financial support to CIMO (PEst-OE/AGR/UI0690/2011), Â. Fernandes (SFRH/BD/76019/2011) and J.C.M. Barreira (SFRH/BPD/72802/2010). They also thank to the Local Health Unit of Mirandela, Northeast of Portugal, for all the support and to INCT - Institute of Nuclear Chemistry and Technology, in Warsaw, Poland for electron-beam irradiation

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

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    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

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    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

    Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

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    The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

    Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

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    A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters

    Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

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    This paper constructs the reduction of heterotic MM-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe
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