Particularidades del metabolismo de las poliaminas y su posible aplicación en medicina veterinaria

Las poliaminas (PAs) putrecsina (Pu), espermidina (Spd) y espermina (Spm) son cationes orgánicos ubicuos con cargas distribuidas que interactúan con varias macromoléculas, y afectan muchas funciones a nivel celular. Las PAs son esenciales para el crecimiento normal de la célula y la actividad creciente de su enzima limitante Ornitinadescarboxilasa (ODC), más allá de su umbral mínimo e indefinido, pueden inducira la transformación y la formación de tumores. Dado que en humanos se ha demostrado una relación entre contenido de PAs y enfermedades y dada la importancia creciente que tiene la ODC en la regulación de la biosíntesis de las PAs, así como la participación de dichas aminas en diversos procesos biológicos, hacen recomendable cuantificar estas moléculas en diversos fluidos incluyendo el plasma, la orina y el suero. Lapresente reseña enfatiza en todos aquellos aspectos metabólicos y de características físico-químicas referentesa las PAs, a la ODC, su antizima (AZ) y al inhibidor de la AZ (AZI), que son muy particulares y representanuna estrategia poco común de la fisiología celular. Así como pretende estimular la generación de resultados que permitan una mayor aplicación en el diagnóstico de distintas enfermedades o esclarecimiento de procesos degenerativos, así como posibles aplicaciones en ciencias veterinarias

SUPRIMENTO ARTERIAL PARA A BOLSA CLOACAL DE GALINHAS (Gallus gallus Linnaeus, 1758) DA LINHAGEM LABEL ROUGE

Foram estudados a origem, o número e a ordenação dos ramos arteriais destinados à bolsa cloacal em 30 exemplares de Gallus gallus, da linhagem Label Rouge, machos e fêmeas, com idade entre oito e dez semanas. Após injetado o sistema arterial desses animais com solução corada de Neoprene látex, seguido de fixação em solução aquosa de formol a 10 % e ulteriormente dissecados, verificou-se que: a) uma artéria bursocloacal direita esteve presente em 24 dos casos (80,00%), ao passo que a artéria bursocloacal esquerda foi confirmada em 29 dos exemplares (96,66%); b) a bolsa cloacal foi irrigada por um ou dois ramos cloacais, oriundos da artéria bursocloacal ipsilateral; c) a artéria cloacal direita ocorreu em 20 casos (66,66%) e a artéria cloacal esquerda em 9 casos (30,00%), ocasiões em que cediam apenas um ramo; d) o número de ramos arteriais, independentemente de sua origen, variou de dois a quatro, sendo a sua disposição de maneira própria para cada exemplar examinado. Arterial supply for the cloacal bursa of the Rouge Lineage fowl Gallus gallus (Linnaeus, 1758) Abstract A study has been carried out on the origin, number and disposition of the cloacal bursa arterial branches from tirthy male and female fowls (Gallus gallus), of the Label Rouge lineage, ageing between eight and ten weeks. After being injected the arterial system of those animals with a colored solution of Neoprene latex, they were soon after fixed in an 10% aqueous solution of formalin and dissected. The following observations were carried out: a) a right burso cloacal artery was present in 24 of the cases (80.00%), while the left bursocloacal artery was confirmed in 29 of the cases (96.66%); b) the cloacal bursa was irrigated by one or two cloacal branches of the ipsilateral bursocloacal artery; c) the right cloacal artery is present in 20 cases (66.66%) and the left cloacal artery in 9 cases (30.00%), with only one branch; d) the number of arterial branches, independent of origin

Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV

We report the results of a study of color coherence effects in ppbar collisions based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8 TeV. Initial-to-final state color interference effects are studied by examining particle distribution patterns in events with a W boson and at least one jet. The data are compared to Monte Carlo simulations with different color coherence implementations and to an analytic modified-leading-logarithm perturbative calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

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

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

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

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

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