85 research outputs found

    Interleukin 15 Levels in Serum May Predict a Severe Disease Course in Patients with Early Arthritis

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    Background: Interleukin-15 (IL-15) is thought to be involved in the physiopathological mechanisms of RA and it can be detected in the serum and the synovial fluid of inflamed joints in patients with RA but not in patients with osteoarthritis or other inflammatory joint diseases. Therefore, the objective of this work is to analyse whether serum IL-15 (sIL-15) levels serve as a biomarker of disease severity in patients with early arthritis (EA). Methodology and Results: Data from 190 patients in an EA register were analysed (77.2% female; median age 53 years; 6-month median disease duration at entry). Clinical and treatment information was recorded systematically, especially the prescription of disease modifying anti-rheumatic drugs. Two multivariate longitudinal analyses were performed with different dependent variables: 1) DAS28 and 2) a variable reflecting intensive treatment. Both included sIL-15 as predictive variable and other variables associated with disease severity, including rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPA). Of the 171 patients (638 visits analysed) completing the follow-up, 71% suffered rheumatoid arthritis and 29% were considered as undifferentiated arthritis. Elevated sIL-15 was detected in 29% of this population and this biomarker did not overlap extensively with RF or ACPA. High sIL-15 levels (ÎČ Coefficient [95% confidence interval]: 0.12 [0.06-0.18]; p&0.001) or ACPA (0.34 [0.01-0.67]; p = 0.044) were significantly and independently associated with a higher DAS28 during follow-up, after adjusting for confounding variables such as gender, age and treatment. In addition, those patients with elevated sIL-15 had a significantly higher risk of receiving intensive treatment (RR 1.78, 95% confidence interval 1.18-2.7; p = 0.007). Conclusions: Patients with EA displaying high baseline sIL-15 suffered a more severe disease and received more intensive treatment. Thus, sIL-15 may be a biomarker for patients that are candidates for early and more intensive treatmentThe work of Belen DĂ­az-SĂĄnchez was supported by the RETICS Programme (Programa de Redes TemĂĄticas de InvestigaciĂłn Colaborativa [Colaborative Research Thematic Network Programme]; RD08/0075 - RIER [Red de InflamaciĂłn y Enfermedades ReumĂĄticas; Inflammation and Rheumatic Diseases Network]) from the Instituto de Salud Carlos III, Spain (URL: www.isciii.es) within the VI National Plan for I+D+I 2008–2011 (FEDER). The work of Isidoro GonzĂĄlez-Álvaro was in part supported by a grant for the Intensification of the Research Tasks in the National Health Care System from Instituto de Salud Carlos III, Spain. The consumables for measurements and data analysis were supported by a Fondo de InvestigaciĂłn Sanitaria grant (08/0754) from the Instituto de Salud Carlos II

    Test of lepton universality in b→sℓ+ℓ−b \rightarrow s \ell^+ \ell^- decays

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    The first simultaneous test of muon-electron universality using B+→K+ℓ+ℓ−B^{+}\rightarrow K^{+}\ell^{+}\ell^{-} and B0→K∗0ℓ+ℓ−B^{0}\rightarrow K^{*0}\ell^{+}\ell^{-} decays is performed, in two ranges of the dilepton invariant-mass squared, q2q^{2}. The analysis uses beauty mesons produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9 fb−1\mathrm{fb}^{-1}. Each of the four lepton universality measurements reported is either the first in the given q2q^{2} interval or supersedes previous LHCb measurements. The results are compatible with the predictions of the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-046.html (LHCb public pages

    Observation of Two New Excited Ξb0 States Decaying to Λb0 K-π+

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    Two narrow resonant states are observed in the Λb0K-π+ mass spectrum using a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6 fb-1. The minimal quark content of the Λb0K-π+ system indicates that these are excited Ξb0 baryons. The masses of the Ξb(6327)0 and Ξb(6333)0 states are m[Ξb(6327)0]=6327.28-0.21+0.23±0.12±0.24 and m[Ξb(6333)0]=6332.69-0.18+0.17±0.03±0.22 MeV, respectively, with a mass splitting of Δm=5.41-0.27+0.26±0.12 MeV, where the uncertainties are statistical, systematic, and due to the Λb0 mass measurement. The measured natural widths of these states are consistent with zero, with upper limits of Γ[Ξb(6327)0]<2.20(2.56) and Γ[Ξb(6333)0]<1.60(1.92) MeV at a 90% (95%) credibility level. The significance of the two-peak hypothesis is larger than nine (five) Gaussian standard deviations compared to the no-peak (one-peak) hypothesis. The masses, widths, and resonant structure of the new states are in good agreement with the expectations for a doublet of 1D Ξb0 resonances

    Precision measurement of CP\it{CP} violation in the penguin-mediated decay Bs0→ϕϕB_s^{0}\rightarrow\phi\phi

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    A flavor-tagged time-dependent angular analysis of the decay Bs0→ϕϕB_s^{0}\rightarrow\phi\phi is performed using pppp collision data collected by the LHCb experiment at % at s=13\sqrt{s}=13 TeV, the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb^{-1}. The CP\it{CP}-violating phase and direct CP\it{CP}-violation parameter are measured to be ϕssˉs=−0.042±0.075±0.009\phi_{s\bar{s}s} = -0.042 \pm 0.075 \pm 0.009 rad and ∣λ∣=1.004±0.030±0.009|\lambda|=1.004\pm 0.030 \pm 0.009 , respectively, assuming the same values for all polarization states of the ϕϕ\phi\phi system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using pppp collisions at center-of-mass energies of 7 and 8 TeV, yielding ϕssˉs=−0.074±0.069\phi_{s\bar{s}s} = -0.074 \pm 0.069 rad and ∣lambda∣=1.009±0.030|lambda|=1.009 \pm 0.030. This is the most precise study of time-dependent CP\it{CP} violation in a penguin-dominated BB meson decay. The results are consistent with CP\it{CP} symmetry and with the Standard Model predictions.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-001.html (LHCb public pages

    Observation of a resonant structure near the Ds+Ds−D_s^+ D_s^- threshold in the B+→Ds+Ds−K+B^+\to D_s^+ D_s^- K^+ decay

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    An amplitude analysis of the B+→Ds+Ds−K+B^+\to D_s^+ D_s^- K^+ decay is carried out to study for the first time its intermediate resonant contributions, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV. A near-threshold peaking structure, referred to as X(3960)X(3960), is observed in the Ds+Ds−D_s^+ D_s^- invariant-mass spectrum with significance greater than 12 standard deviations. The mass, width and the quantum numbers of the structure are measured to be 3956±5±103956\pm5\pm10 MeV, 43±13±843\pm13\pm8 MeV and JPC=0++J^{PC}=0^{++}, respectively, where the first uncertainties are statistical and the second systematic. The properties of the new structure are consistent with recent theoretical predictions for a state composed of ccˉssˉc\bar{c}s\bar{s} quarks. Evidence for an additional structure is found around 4140 MeV in the Ds+Ds−D_s^+ D_s^- invariant mass, which might be caused either by a new resonance with the 0++0^{++} assignment or by a J/ψϕ↔Ds+Ds−J/\psi \phi\leftrightarrow D_s^+ D_s^- coupled-channel effect.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-018.html (LHCb public pages

    Precise determination of the B-s(0)-B-s(-0) oscillation frequency

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    Mesons comprising a beauty quark and a strange quark can oscillate between particle (B0s) and antiparticle (B0s) flavour eigenstates, with a frequency given by the mass difference between heavy and light mass eigenstates, deltams. Here we present ameasurement of deltams using B0s2DsPi decays produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The oscillation frequency is found to be deltams = 17.7683 +- 0.0051 +- 0.0032 ps-1, where the first uncertainty is statistical and the second systematic. This measurement improves upon the current deltams precision by a factor of two. We combine this result with previous LHCb measurements to determine deltams = 17.7656 +- 0.0057 ps-1, which is the legacy measurement of the original LHCb detector.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2021-005.html (LHCb public pages

    Search for the doubly heavy baryons Omega(0)(bc) and Xi(0)(bc) decaying to Lambda(+)(c)pi(-) and Xi(+)(c)pi-

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    Measurement of the ratios of branching fractions R(D*) and R(D0)

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    The ratios of branching fractions R ( D ∗ ) ≡ B ( ÂŻ B → D ∗ τ − ÂŻ Îœ τ ) / B ( ÂŻ B → D ∗ ÎŒ − ÂŻ Îœ ÎŒ ) and R ( D 0 ) ≡ B ( B − → D 0 τ − ÂŻ Îœ τ ) / B ( B − → D 0 ÎŒ − ÂŻ Îœ ÎŒ ) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0     fb − 1 of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ − → ÎŒ − Îœ τ ÂŻ Îœ ÎŒ . The measured values are R ( D ∗ ) = 0.281 ± 0.018 ± 0.024 and R ( D 0 ) = 0.441 ± 0.060 ± 0.066 , where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ = − 0.43 . The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model

    Measurement of antiproton production from antihyperon decays in p He collisions at √sNN = 110 GeV

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    The interpretation of cosmic antiproton flux measurements from space-borne experiments is currently limited by the knowledge of the antiproton production cross-section in collisions between primary cosmic rays and the interstellar medium. Using collisions of protons with an energy of 6.5TeV incident on helium nuclei at rest in the proximity of the interaction region of the LHCb experiment, the ratio of antiprotons originating from antihyperon decays to prompt production is measured for antiproton momenta between 12 and 110GeV. The dominant antihyperon contribution, namely Λ¯→pÂŻÏ€+ decays from promptly produced Λ¯ particles, is also exclusively measured. The results complement the measurement of prompt antiproton production obtained from the same data sample. At the energy scale of this measurement, the antihyperon contributions to antiproton production are observed to be significantly larger than predictions of commonly used hadronic production models
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