707 research outputs found

    Cardiotrophin-1 promotes a high survival rate in rabbits with lethal fulminant hepatitis of viral origin

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    Rabbit hemorrhagic disease virus (RHDV) causes lethal fulminant hepatitis closely resembling acute liver failure (ALF) in humans. In this study, we investigated whether cardiotrophin-1 (CT-1), a cytokine with hepatoprotective properties, could attenuate liver damage and prolong survival in virus-induced ALF. Twenty-four rabbits were infected with 2 × 10(4) hemagglutination units of RHDV. Twelve received five doses of CT-1 (100 μg/kg) starting at 12 h postinfection (hpi) (the first three doses every 6 h and then two additional doses at 48 and 72 hpi), while the rest received saline. The animals were analyzed for survival, serum biochemistry, and viral load. Another cohort (n = 22) was infected and treated similarly, but animals were sacrificed at 30 and 36 hpi to analyze liver histology, viral load, and the expression of factors implicated in liver damage and repair. All infected rabbits that received saline died by 60 hpi, while 67% of the CT-1-treated animals survived until the end of the study. Treated animals showed improved liver function and histology, while the viral loads were similar. In the livers of CT-1-treated rabbits we observed reduction of oxidative stress, diminished PARP1/2 and JNK activation, and decreased inflammatory reaction, as reflected by reduced expression of tumor necrosis factor alpha, interleukin-1β, Toll-like receptor 4, VCAM-1, and MMP-9. In addition, CT-1-treated rabbits exhibited marked upregulation of TIMP-1 and increased expression of cytoprotective and proregenerative growth factors, including platelet-derived growth factor B, epidermal growth factor, platelet-derived growth factor receptor β, and c-Met. In conclusion, in a lethal form of acute viral hepatitis, CT-1 increases animal survival by attenuating inflammation and activating cytoprotective mechanisms, thus representing a promising therapy for ALF of viral origin

    Mapping the ionized gas of the metal-poor HII galaxy PHL 293B with MEGARA

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    Here we report the first spatially resolved spectroscopic study for the galaxy PHL293B using the high-resolution GTC/MEGARA IFU. PHL293B is a local, extremely metal-poor, high ionization galaxy. This makes PHL 293B an excellent analogue for galaxies in the early Universe. The MEGARA aperture (~12.5''x 11.3'') covers the entire PHL 293B main body and its far-reaching ionized gas. We created and discussed maps of all relevant emission lines, line ratios and physical-chemical properties of the ionized ISM. The narrow emission gas appears to be ionized mainly by massive stars according to the observed diganostic line ratios, regardless of the position across the MEGARA aperture. We detected low intensity broad emission components and blueshifted absorptions in the Balmer lines (Hα\alpha,Hβ\beta) which are located in the brightest zone of the galaxy ISM. A chemically homogeneity, across hundreds of parsecs, is observed in O/H. We take the oxygen abundance 12+log(O/H)=7.64 ±\pm 0.06 derived from the PHL293B integrated spectrum as the representative metallicity for the galaxy. Our IFU data reveal for the first time that the nebular HeII4686 emission from PHL 293B is spatially extended and coincident with the ionizing stellar cluster, and allow us to compute its absolute HeII ionizing photon flux. Wolf-Rayet bumps are not detected excluding therefore Wolf-Rayet stars as the main HeII excitation source. The origin of the nebular HeII4686 is discussed.Comment: 14 pages, 9 Figures, 3 Tables; Accepted for publication in MNRA

    Effectiveness of rotavirus vaccination in Spain

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    With the aim of determining rotavirus vaccine effectiveness (RVVE) in Spain, from Oct-2008/Jun-2009, 467 consecutive children below 2 years old with acute gastroenteritis (AGE) were recruited using a pediatric research network (ReGALIP-www.regalip.org) that includes primary, emergency and hospital care settings. Of 467 enrolled children, 32.3% were rotavirus positive and 35.0% had received at least one dose of any rotavirus vaccine. RRVE to prevent any episode of rotavirus AGE was 91.5% (95% CI: 83.7%-95.6%). RVVE to prevent hospitalization by rotavirus AGE was 95.6% (85.6-98.6%). No differences in RVVE were found regarding the vaccine used. Rotavirus vaccines have showed an outstanding effectiveness in Spain

    Vigilancia de los serotipos y susceptibilidad antimicrobiana de Haemophilus influenzae en Colombia, 1994-2002.

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    Invasive disease caused by Haemophilus influenzae serotype b results in high rates of morbidity and mortality among children. In 1994, the Microbiology Group at the Instituto Nacional de Salud (Colombia) initiated a program to detect antimicrobial resistance in H. influenzae. Invasive isolates were collected by hospitals and public health laboratories as part of surveillance programs for acute respiratory infections and acute bacterial meningitis. To determine the evolution of serotypes and antimicrobial resistance patterns, invasive H. influenzae isolates collected from 1994 to 2002 were compared, and the impact of Hib conjugated vaccine in Colombia was reassessed. The analysis included 683 isolates, 379 (55.5%) were recovered from male patients, 370 (54.2%) from children under one year, 227 (33.2%) from children aged 1 to 5, 19 (2.8%) from children aged 6 to 14, and 38 (5.6%) from children over 14 years; 29 (4.2%) with no age data. Clinical classification recorded 493 (72.2%) of the samples were from patients with meningitis, 181 (26.5%) with pneumonia, and 9 (0.9%) with other diseases. Eighty five percent of isolates corresponded to H. influenzae serotype b, 12.9% were non capsular, and 2.0% corresponded to other serotypes (10 a, 1 d, 1 e and 2 f). Of the total number of isolates, 12.0% produced beta lactamase, 13.9% were resistant to ampicillin, 12.7% to trimethoprim sulfamethoxazole (SXT), 5.4% to chloramphenicol, 1% to cefuroxime. All isolates were susceptible to ceftriaxone. During the 10-year period, resistance to SXT increased from 5% to 13%. A significant decrease in meningitis cases was detected among children under one-year old and in the 1 to 5 age group. Before introducing the vaccine, an annual average of 43 and 23 isolates for each of these groups were received. During 2002, 10 and 6 isolates, respectively, were received for each group. Surveillance of invasive H. influenzae isolates has allowed the evaluation of Hib vaccine impact, as well as the detection of an increase of non-capsular isolates, and changes in resistance patterns.La enfermedad invasora causada por Haemophilus influenzae, serotipo b, ha sido una de las mayores causas de morbilidad y mortalidad en la población infantil; afortunadamente, en algunos países con amplia cobertura de la vacuna conjugada esta situación ha cambiado. En 1994 se inició en el Grupo de Microbiología un programa de vigilancia de la susceptibilidad antimicrobiana y de los serotipos de aislamientos invasores de H. influenzae, remitidos por los hospitales y Laboratorios de Salud Pública del país como componente de los programas de vigilancia en red de infección respiratoria aguda y meningitis bacteriana aguda. El objetivo de este trabajo fue determinar la evolución de los serotipos y los patrones de susceptibilidad antimicrobiana de los aislamientos invasores de H. influenzae obtenidos de 1994 al 2002 y realizar un nuevo análisis sobre el impacto de la vacuna conjugada de H. influenzae, serotipo b, en Colombia. De 1994 a 2002 se han estudiado 683 aislamientos; 379 (55,5%) de pacientes del género masculino; 370 (54,2%) de menores de 1 año; 227 (33,2%) de 1 a 5 años; 19 (2,8%) de 6 a 14 años; 38 (5,6%) de mayores de 14 años, y de 29 (4,2%) no se tenía el dato de la edad; 493 (72,2%) fueron recuperados de pacientes con meningitis, 181 (26,5%) de neumonía y 9 (0,9%) de otras enfermedades. El 85,1% de los aislamientos fueron H. influenzae, serotipo b, 12,9% no capsulares y 2,0% de otros serotipos (10 a, 1 d, 1 e y 2 f). Del total de aislamientos, 12% fueron productores de beta-lactamasa; 13,9%, resistentes a ampicilina; 12,7%, a trimetoprim sulfametoxazol (SXT); 5,4%, a cloranfenicol, y 1% a cefuroxima; todos fueron sensibles a ceftriaxona. Durante este período se observó un incremento en la resistencia de los aislamientos a SXT (5% al 13%), pero la diferencia no fue estadísticamente significativa (p=0,1). Con la vigilancia se pudo determinar una disminución significativa de los casos de meningitis en los menores de 1 año y en el grupo de 1 a 5 años; antes de la introducción de la vacuna de Hib, se recibía un promedio anual de 43 y 23 aislamientos de cada uno de estos grupos y en el 2002 se recibieron 10 y 6, respectivamente (

    Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

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    The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

    Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

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    The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

    Measurement of the flavour composition of dijet events in pp collisions at root s=7 TeV with the ATLAS detector

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    This paper describes a measurement of the flavour composition of dijet events produced in pp collisions at √s=7 TeV using the ATLAS detector. The measurement uses the full 2010 data sample, corresponding to an integrated luminosity of 39 pb−1. Six possible combinations of light, charm and bottom jets are identified in the dijet events, where the jet flavour is defined by the presence of bottom, charm or solely light flavour hadrons in the jet. Kinematic variables, based on the properties of displaced decay vertices and optimised for jet flavour identification, are used in a multidimensional template fit to measure the fractions of these dijet flavour states as functions of the leading jet transverse momentum in the range 40 GeV to 500 GeV and jet rapidity |y|<2.1. The fit results agree with the predictions of leading- and next-to-leading-order calculations, with the exception of the dijet fraction composed of bottom and light flavour jets, which is underestimated by all models at large transverse jet momenta. The ability to identify jets containing two b-hadrons, originating from e.g. gluon splitting, is demonstrated. The difference between bottom jet production rates in leading and subleading jets is consistent with the next-to-leading-order predictions

    Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

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    The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry
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