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1.
Hong Kong Med J ; 23(2): 117-21, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28232641

RESUMO

INTRODUCTION: Coagulopathy-associated intracerebral haemorrhage has become increasingly common because of the rising demand in the ageing population for anticoagulation for atrial fibrillation. This study compared the clinical features and neurological outcomes of intracerebral haemorrhage in patients with atrial fibrillation who were prescribed warfarin with those who were not. METHODS: This was a retrospective matched case series of patients with intracerebral haemorrhage from three tertiary hospitals in Hong Kong from 1 January 2006 to 31 December 2011. Patients who developed intracerebral haemorrhage and who were prescribed warfarin for atrial fibrillation (ICH-W group) were compared with those with intracerebral haemorrhage and not prescribed warfarin (ICH-C group); they were matched for age and gender in 1:1 ratio. Clinical features and neurological outcomes were compared, and the impact of coagulopathy on haematoma size was also studied. RESULTS: We identified 114 patients in the ICH-W group with a mean age of 75 years. Both ICH-W and ICH-C groups had a median intracerebral haemorrhage score of 2. There was a non-statistically significant trend of higher intracerebral haemorrhage volume in the ICH-W group (12.9 mL vs 10.5 mL). The median modified Rankin Scale and the proportion with good recovery (modified Rankin Scale score ≤3) at 6 months were comparable. Nonetheless, ICH-W patients had higher hospital mortality (51.8% vs 36.0%; P=0.02) and 6-month mortality (60.5% vs 43.0%; P=0.01) than ICH-C patients. Overall, 60% of ICH-W patients had their admission international normalised ratio within the therapeutic range during intracerebral haemorrhage, and 14% had a subtherapeutic admission international normalised ratio. International normalised ratio at admission was not associated with intracerebral haemorrhage volume or neurological outcome. CONCLUSION: Warfarin-associated intracerebral haemorrhage in patients with atrial fibrillation carried a higher stroke mortality than the non-warfarinised patients.


Assuntos
Anticoagulantes/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/mortalidade , Varfarina/efeitos adversos , Idoso , Estudos de Casos e Controles , Hemorragia Cerebral/diagnóstico por imagem , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
2.
Phys Rev Lett ; 114(9): 092003, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25793804

RESUMO

Based on data samples collected with the BESIII detector at the BEPCII collider at nine center of mass energies from 4.21 to 4.42 GeV, we search for the production of e^{+}e^{-}→ωχ_{cJ} (J=0, 1, 2). The process e^{+}e^{-}→ωχ_{c0} is observed for the first time, and the Born cross sections at sqrt[s]=4.23 and 4.26 GeV are measured to be (55.4±6.0±5.9) and (23.7±5.3±3.5) pb, respectively, where the first uncertainties are statistical and the second are systematic. The ωχ_{c0} signals at the other seven energies and the e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} signals are not significant, and the upper limits on the cross sections are determined. By examining the ωχ_{c0} cross section as a function of center of mass energy, we find that it is inconsistent with the line shape of the Y(4260) observed in e^{+}e^{-}→π^{+}π^{-}J/ψ. Assuming the ωχ_{c0} signals come from a single resonance, we extract the mass and width of the resonance to be (4230±8±6) MeV/c^{2} and (38±12±2) MeV, respectively, and the statistical significance is more than 9σ.

3.
Phys Rev Lett ; 112(2): 022001, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24484002

RESUMO

We report on a study of the process e+ e- → π± (DD*)∓ at sqrt[s] = 4.26 GeV using a 525 pb(-1) data sample collected with the BESIII detector at the BEPCII storage ring. A distinct charged structure is observed in the (DD*)∓ invariant mass distribution. When fitted to a mass-dependent-width Breit-Wigner line shape, the pole mass and width are determined to be Mpole = (3883.9±1.5(stat)±4.2(syst)) MeV/c2 and Γpole = (24.8±3.3(stat)±11.0(syst)) MeV. The mass and width of the structure, which we refer to as Zc(3885), are 2σ and 1σ, respectively, below those of the Zc(3900) → π± J/ψ peak observed by BESIII and Belle in π+ π- J/ψ final states produced at the same center-of-mass energy. The angular distribution of the πZc(3885) system favors a JP = 1+ quantum number assignment for the structure and disfavors 1- or 0-. The Born cross section times the DD* branching fraction of the Zc(3885) is measured to be σ(e+ e- → π± Zc(3885)∓)×B(Zc(3885)∓ → (DD*)∓) = (83.5±6.6(stat)±22.0(syst)) pb. Assuming the Zc(3885) → DD* signal reported here and the Zc(3900) → πJ/ψ signal are from the same source, the partial width ratio (Γ(Zc(3885) → DD*)/Γ(Zc(3900) → πJ/ψ)) = 6.2±1.1(stat)±2.7(syst) is determined.

4.
Phys Rev Lett ; 113(21): 212002, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25479489

RESUMO

Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at center-of-mass energies of sqrt[s]=4.23, 4.26, and 4.36 GeV, we observe e(+)e(-)→π(0)π(0)hc for the first time. The Born cross sections are measured and found to be about half of those of e(+)e(-)→π(+)π(-)hc within less than 2σ. In the π(0)hc mass spectrum, a structure at 4.02 GeV/c(2) is found. It is most likely to be the neutral isospin partner of the Zc(4020)(±) observed in the process of e(+)e(-)→π(+)π(-)hc being found. A fit to the π(0)hc invariant mass spectrum, with the width of the Zc(4020)(0) fixed to that of its charged isospin partner and possible interferences with non-Zc(4020)(0) amplitudes neglected, gives a mass of (4023.9±2.2±3.8) MeV/c(2) for the Zc(4020)(0), where the first error is statistical and the second systematic.

5.
Phys Rev Lett ; 112(13): 132001, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24745407

RESUMO

We study the process e+ e- →(D* D*)± π∓ at a center-of-mass energy of 4.26 GeV using a 827 pb(-1) data sample obtained with the BESIII detector at the Beijing Electron Positron Collider. Based on a partial reconstruction technique, the Born cross section is measured to be (137±9±15) pb. We observe a structure near the (D* D*)± threshold in the π∓ recoil mass spectrum, which we denote as the Zc±(4025). The measured mass and width of the structure are (4026.3±2.6±3.7) MeV/c2 and (24.8±5.6±7.7) MeV, respectively. Its production ratio σ(e+ e- → Zc±(4025)π∓ → (D* D*)± π∓)/σ(e+ e- → (D* D*)± π∓) is determined to be 0.65±0.09±0.06. The first uncertainties are statistical and the second are systematic.

6.
Phys Rev Lett ; 112(25): 251801, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-25014804

RESUMO

Using a sample of 1.3 × 10(9) J/ψ events collected with the BESIII detector, we report the first observation of η(')→π(+)π(-)π(+)π(-) and η(')→π(+)π(-)π(0)π(0). The measured branching fractions are B(η(')→π(+)π(-)π(+)π(-)) = [8.53 ± 0.69(stat.) ± 0.64(syst.)]×10(-5) and B(η(')→π(+)π(-)π(0) π(0)) = [1.82 ± 0.35(stat.) ± 0.18(syst.)] × 10(-4), which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vector-meson dominance.

7.
Phys Rev Lett ; 112(9): 092001, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24655246

RESUMO

With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e+e-→ γX(3872) is observed for the first time with a statistical significance of 6.3σ. The measured mass of the X(3872) is (3871.9 ± 0.7s tat ± 0.2 syst) MeV/c(2), in agreement with previous measurements. Measurements of the product of the cross section σ[e+e- → γX(3872)] and the branching fraction B[X(3872)→π+π-J/ψ] at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260) → γX(3872).

8.
Phys Rev Lett ; 110(25): 252001, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23829729

RESUMO

We study the process ee+ e- → π+ π- J/ψ at a center-of-mass energy of 4.260 GeV using a 525 pb(-1) data sample collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross section is measured to be (62.9±1.9±3.7) pb, consistent with the production of the Y(4260). We observe a structure at around 3.9 GeV/c2 in the π(±)J/ψ mass spectrum, which we refer to as the Z(c)(3900). If interpreted as a new particle, it is unusual in that it carries an electric charge and couples to charmonium. A fit to the π(±)J/ψ invariant mass spectrum, neglecting interference, results in a mass of (3899.0±3.6±4.9) MeV/c2 and a width of (46±10±20) MeV. Its production ratio is measured to be R = (σ(e+ e- → π(±)Z(c)(3900)(∓) → π+ π- J/ψ)/σ(e+ e- → π+ π- J/ψ)) = (21.5±3.3±7.5)%. In all measurements the first errors are statistical and the second are systematic.

9.
Phys Rev Lett ; 111(24): 242001, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24483645

RESUMO

We study e+e-→π+π-hc at center-of-mass energies from 3.90 to 4.42 GeV by using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections are measured at 13 energies and are found to be of the same order of magnitude as those of e+e-→π+π-J/ψ but with a different line shape. In the π±hc mass spectrum, a distinct structure, referred to as Zc(4020), is observed at 4.02 GeV/c2. The Zc(4020) carries an electric charge and couples to charmonium. A fit to the π±hc invariant mass spectrum, neglecting possible interferences, results in a mass of (4022.9±0.8±2.7) MeV/c2 and a width of (7.9±2.7±2.6) MeV for the Zc(4020), where the first errors are statistical and the second systematic. The difference between the parameters of this structure and the Zc(4025) observed in the D*D[over ¯]* final state is within 1.5σ, but whether they are the same state needs further investigation. No significant Zc(3900) signal is observed, and upper limits on the Zc(3900) production cross sections in π±hc at center-of-mass energies of 4.23 and 4.26 GeV are set.

10.
Phys Rev Lett ; 110(2): 022001, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23383891

RESUMO

Based on 106×10(6)ψ(3686) events collected with the BESIII detector at the BEPCII facility, a partial wave analysis of ψ(3686)→ppπ0 is performed. The branching fraction of this channel has been determined to be B(ψ(3686)→ppπ0)=(1.65±0.03±0.15)×10(-4). In this decay, 7 N* intermediate resonances are observed. Among these, two new resonances, N(2300) and N(2570) are significant, one 1/2+ resonance with a mass of 2300(-30-0)(+40+109) MeV/c2 and width of 340(-30-58)(+30+110) MeV/c2, and one 5/2- resonance with a mass of 2570(-10-10)(+19+34) MeV/c2 and width of 250(-24-21)(+14+69) MeV/c2. For the remaining 5 N* intermediate resonances [N(1440), N(1520), N(1535), N(1650) and N(1720)], the analysis yields mass and width values that are consistent with those from established resonances.

11.
Phys Rev Lett ; 108(11): 112003, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22540467

RESUMO

A partial wave analysis of the pp¯ mass-threshold enhancement in the reaction J/ψ→γpp¯ is used to determine its J(PC) quantum numbers to be 0(-+), its peak mass to be below threshold at M=1832(-5)(+19)(stat)(-17)(+18)(syst)±19(model) MeV/c(2), and its total width to be Γ<76 MeV/c(2) at the 90% C.L. The product of branching ratios is measured to be BR[J/ψ→γX(pp¯)]BR[X(pp¯)→pp¯]=[9.0(-1.1)(+0.4)(stat)(-5.0)(+1.5)(syst)±2.3(model)]×10(-5). A similar analysis performed on ψ(3686)→γpp¯ decays shows, for the first time, the presence of a corresponding enhancement with a production rate relative to that for J/ψ decays of R=[5.08(-0.45)(+0.71)(stat)(-3.58)(+0.67)(syst)±0.12(model)]%.

12.
Phys Rev Lett ; 108(18): 182001, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22681064

RESUMO

The decays J/ψ → γ π+ π- π0 and J/ψ → γ π0 π0 π0 are analyzed using a sample of 225×10(6) J/ψ events collected with the BESIII detector. The decay of η(1405) → f(0)(980)π0 with a large isospin violation is observed for the first time. The width of the f(0)(980) observed in the dipion mass spectra is anomalously narrower than the world average. Decay rates for three-pion decays of the η' are also measured precisely.

13.
Phys Rev Lett ; 108(22): 222002, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23003588

RESUMO

The mass and width of the lowest-lying S-wave spin singlet charmonium state, the η(c), are measured using a data sample of 1.06×10(8) ψ(3686) decays collected with the BESIII detector at the BEPCII storage ring. We use a model that incorporates full interference between the signal reaction, ψ(3686)→γη(c), and a nonresonant radiative background to describe the line shape of the η(c) successfully. We measure the η(c) mass to be 2984.3±0.6±0.6 MeV/c(2) and the total width to be 32.0±1.2±1.0 MeV, where the first errors are statistical and the second are systematic.

14.
Phys Rev Lett ; 109(17): 172002, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-23215179

RESUMO

The two-photon transition ψ(3686)→γγJ/ψ is studied in a sample of 1.06×10(8) ψ(3686) decays collected by the BESIII detector. The branching fraction is measured to be (3.1±0.6(stat)(-1.0)(+0.8)(syst))×10(-4) using J/ψ→e(+)e(-) and J/ψ→µ(+)µ(-) decays, and its upper limit is estimated to be 4.5×10(-4) at the 90% confidence level. This work represents the first measurement of a two-photon transition among charmonium states. The orientation of the ψ(3686) decay plane and the J/ψ polarization in this decay are also studied. In addition, the product branching fractions of sequential E1 transitions ψ(3686)→γχ(cJ) and χ(cJ)→γJ/ψ(J=0,1,2) are reported.

15.
Phys Rev Lett ; 109(4): 042003, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-23006078

RESUMO

Using a sample of 106×10(6) ψ(3686) events collected with the BESIII detector at the BEPCII storage ring, we have made the first measurement of the M1 transition between the radially excited charmonium S-wave spin-triplet and the radially excited S-wave spin-singlet states: ψ(3686)→γη(c)(2S). Analyses of the processes ψ(3686)→γη(c)(2S) with η(c)(2S)→K(S)(0)K(±)π(∓) and K(+)K(-)π(0) give an η(c)(2S) signal with a statistical significance of greater than 10 standard deviations under a wide range of assumptions about the signal and background properties. The data are used to obtain measurements of the η(c)(2S) mass (M(η(c)(2S))=3637.6±2.9(stat)±1.6(syst) MeV/c(2)), width (Γ(η(c)(2S))=16.9±6.4(stat)±4.8(syst) MeV), and the product branching-fraction (B(ψ(3686)→γη(c)(2S))×B(η(c)(2S)→KKπ)=(1.30±0.20(stat)±0.30(syst))×10(-5)). Combining our result with a BABAR measurement of B(η(c)(2S)→KKπ), we find the branching fraction of the M1 transition to be B(ψ(3686)→γη(c)(2S))=(6.8±1.1(stat)±4.5(syst))×10(-4).

16.
Phys Rev Lett ; 107(18): 182001, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22107625

RESUMO

We present results of a study of the decay J/ψ → ωηπ+ π- using a sample of (225.2 ± 2.8) × 10(6) J/ψ events collected by the BESIII detector, and report the observation of a new process J/ψ → ωX(1870) with a statistical significance of 7.2σ, in which X(1870) decays to a(0)(±)(980)π±. Fitting to ηπ+ π- mass spectrum yields a mass M = 1877.3 ± 6.3(stat)(-7.4)(+3.4)(syst) MeV/c(2), a width Γ = 57 ± 12(stat)(-4)(+19)(syst) MeV/c(2), and a product branching fraction B(J/ψ → ωX) × B(X→a(0)(±)(980)π±) × B(a(0) (±)(980) → ηπ±) = [1.50 ± 0.26(stat)(-0.36)(+0.72) (syst)] × 10(-4). Signals for J/ψ → ωf(1)(1285) and J/ψ → ω η(1405) are also clearly observed and measured.

17.
Phys Rev Lett ; 107(9): 092001, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21929228

RESUMO

Using (106±4)×10⁻6 ψ(3686) events accumulated with the BESIII detector at the BEPCII e⁺e⁻ collider, we present the first measurement of decays of χ(c1) to vector meson pairs φφ, ωω, and ωφ. The branching fractions are measured to be (4.4±0.3±0.5)×10⁻4, (6.0±0.3±0.7)×10⁻4, and (2.2±0.6±0.2)×10⁻5, for χ(c1)→φφ, ωω, and ωφ, respectively, which indicates that the hadron helicity selection rule is significantly violated in χ(cJ) decays. In addition, the measurement of χ(cJ)→ωφ provides the first indication of the rate of doubly OZI-suppressed χ(cJ) decay. Finally, we present improved measurements for the branching fractions of χ(c0) and χ(c2) to vector meson pairs.

18.
Phys Rev Lett ; 106(7): 072002, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21405509

RESUMO

With a sample of (225.2±2.8)×10(6) J/ψ events registered in the BESIII detector, J/ψ→γπ(+)π(-)η(') is studied using two η(') decay modes: η(')→π(+)π(-)η and η(')→γρ(0). The X(1835), which was previously observed by BESII, is confirmed with a statistical significance that is larger than 20σ. In addition, in the π(+)π(-)η(') invariant-mass spectrum, the X(2120) and the X(2370), are observed with statistical significances larger than 7.2σ and 6.4σ, respectively. For the X(1835), the angular distribution of the radiative photon is consistent with expectations for a pseudoscalar.

19.
Eur Rev Med Pharmacol Sci ; 25(5): 2281-2290, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33755965

RESUMO

OBJECTIVE: Atrial fibrillation (AF) is the most common type of tachycardia. The major injury caused by AF is a systemic embolism. Although AF therapies have evolved substantially, the success rate of sinus rhythm maintenance is relatively low. The reason is the incomplete understanding of the AF mechanisms. MATERIALS AND METHODS: A Gene Expression Omnibus (GEO) dataset (GSE79768) was downloaded. Differentially expressed genes (DEGs) were identified by bioinformatic analysis. Enriched terms and pathways were identified by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. A protein-protein interaction (PPI) network was constructed to determine regulatory genes. CytoHubba and the Molecular Complex Detection (MCODE) algorithm were used to identify potential hub genes and important modules. The Predicting Associated Transcription Factors From Annotated Affinities (PASTAA) method was used to predict transcription factors (TFs). RESULTS: Two hundred thirty-five upregulated DEGs and seventy-seven downregulated DEGs were identified. In the GO biological process, cellular component, and molecular function analyses, positive regulation of cell migration, anchoring junctions, and cell adhesion molecule binding were enriched significantly. The Hippo signalling pathway was the most significantly enriched pathway. In the PPI network analysis, we found that Class A/1 (rhodopsin-like receptors) may be the critical module. Ten hub genes were extracted, including 6 upregulated genes and 4 downregulated genes. CXCR2, TLR4, and CXCR4 may play critical roles in AF. In the TF prediction, we found that Irf-1 may be implicated in AF. CONCLUSIONS: We found that the CXCR4, TLR4, CXCR2 genes, the Hippo signalling pathway and the class A/1 (rhodopsin-like receptors) module may play critical roles in AF occurrence and maintenance, which may provide novel targets for AF treatment.


Assuntos
Fibrilação Atrial/genética , Biologia Computacional , Receptores CXCR4/genética , Receptores de Interleucina-8B/genética , Receptor 4 Toll-Like/genética , Humanos
20.
Phys Rev Lett ; 104(13): 132002, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20481873

RESUMO

We present measurements of the charmonium state h(c)(1P(1)) made with 106x10(6) psi' events collected by BESIII at BEPCII. Clear signals are observed for psi'-->pi0 h(c) with and without the subsequent radiative decay h(c)-->gamma eta(c). First measurements of the absolute branching ratios B(psi'-->pi0 h(c)) = (8.4+/-1.3+/-1.0) x 10(-4) and B(h(c)-->gamma eta(c)) = (54.3+/-6.7+/-5.2)% are presented. A statistics-limited determination of the previously unmeasured h(c) width leads to an upper limit Gamma(h(c))<1.44 MeV (90% confidence). Measurements of M(h(c)) = 3525.40+/-0.13+/-0.18 MeV/c2 and B(psi'-->pi0 h(c)) x B(h(c)-->gamma eta(c)) = (4.58+/-0.40+/-0.50) x 10(-4) are consistent with previous results.

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