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1.
Lupus ; 29(2): 157-164, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31948351

RESUMO

INTRODUCTION: Antiphospholipid syndrome (APS) is associated with greater atherothrombotic risk and endothelial dysfunction, suggesting that endothelial glycocalyx is impaired in this disease. OBJECTIVES: The aim was to investigate the endothelial glycocalyx and the relationship between glycocalyx markers, endothelial dysfunction parameters and atherosclerotic markers in APS. METHODS: A total of 15 primary arterial APS patients and healthy controls were included in the study. Glycocalyx was assessed in both groups by sublingual sidestream dark field imaging and syndecan-1 plasma level. Endothelial function was evaluated by brachial artery flow-mediated dilatation (FMD) and early atherosclerosis by carotid intima media thickness (IMT). Thrombotic profile was also performed by measuring the plasma level of the tissue factor (TF). RESULTS: APS patients had significantly increased syndecan-1 plasma level 38.6 ± 5.0 pg/ml vs. 19.1 ± 3.5 pg/ml; p < 0.01 and a reduced glycocalyx thickness 0.26 ± 0.03 µm vs. 0.75 ± 0.07 µm; p < 0.01 compared with control. FMD was impaired in APS patients compared with control, 5.68% ± 0.42 vs. 8.29 ± 0.30, p < 0.01, respectively. IMT was significantly increased in APS patients compared with control, 0.52 ± 0.13 mm vs. 0.40 ± 0.06 mm, p < 0.01, respectively. Soluble TF, thiobarbituric acid-reactive substances levels were increased in the sera from APS patients compared with control. CONCLUSIONS: This preliminary study supports, for the first time, that in APS patients endothelial glycocalyx is impaired, which could lead to thrombosis, endothelial dysfunction and early atherosclerosis.


Assuntos
Síndrome Antifosfolipídica/fisiopatologia , Aterosclerose/etiologia , Autoanticorpos/imunologia , Endotélio Vascular/fisiopatologia , Glicocálix/patologia , Trombose/etiologia , Adolescente , Adulto , Idoso , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/imunologia , Biomarcadores/sangue , Artéria Braquial/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sindecana-1/sangue , Tromboplastina/análise , Vasodilatação , Adulto Jovem
2.
Transfus Apher Sci ; 58(4): 512-514, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272859

RESUMO

A 31-year-old man with mild hemophilia B developed a herniated disc treated with prednisolone for back pain. Surprisingly, hemostasis result tests performed before epidural infiltration were a normal activated partial thrombin time at 36.1 s. (normal range 27.9-37.7 s.) and factor IX (FIX) level 76% (normal range>70%), 13 days after prednisolone introduction. After a second control with a normal FIX level and a second genetic confirmation of hemophilia, no FIX concentrates was administered to perform the infiltration, which occurred without hemorrhagic complication. This new case of FIX normalization showed the necessity to have a perfect knowledge of patient's treatment to avoid misdiagnosis and a temporary normal hemostasis permit to perform epidural infiltration without replacement therapy.


Assuntos
Fator IX/metabolismo , Hemofilia B/sangue , Deslocamento do Disco Intervertebral/sangue , Deslocamento do Disco Intervertebral/terapia , Prednisolona/administração & dosagem , Adulto , Humanos , Masculino , Tempo de Tromboplastina Parcial
3.
Phys Rev Lett ; 117(19): 192001, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27858429

RESUMO

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.

4.
Phys Rev Lett ; 116(24): 241101, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367377

RESUMO

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.

5.
Res Pract Thromb Haemost ; 8(4): 102462, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39006229

RESUMO

Background: Factor (F)XI deficiency is a rare bleeding disorder with a poor correlation between bleeding tendency and FXI level. Management of pregnant women with FXI deficiency is not clearly established, especially regarding neuraxial analgesia (NA). Objectives: A retrospective multicenter observational study was conducted in French hemostasis centers on pregnant women with FXI of <60 IU/dL. Methods: Data to report were (i) FXI levels before pregnancy and at time of delivery, (ii) type of NA and delivery management modalities, and (iii) possible complications related to NA and bleeding complications. Results: Three hundred fourteen pregnancies in patients with FXI deficiency of <60 IU/dL were reported (from 20 centers); among them, 199 NA procedures have been completed (137 epidurals and 61 spinals, 1 had both). The period of childbirth was mostly from 2014 to 2020 (281/314; 89.5%). Congenital FXI deficiency was established with certainty by investigators in 32.8% patients (n = 103). Previous bleedings were described in 20.4% of the patients (64/314; 45.3% cutaneous, 31.3% gynecologic, and 15.6% postsurgical). Thirteen deliveries had an NA procedure with FXI of <30 IU/dL, 42 with FXI of 30-40 IU/dL, and 118 with FXI of 40-60 IU/dL. Median FXI levels at delivery in the epidural and spinal groups were not significantly different but were significantly lower in the group without NA by medical staff contraindications. There were no complications related to NA. A 17.5% postpartum hemorrhage or excessive postpartum bleeding incidence was reported, which is consistent with previous data. Conclusion: Our data support the use of a 30 IU/dL FXI threshold for NA, as suggested by the French proposals published in August 2023.

6.
Phys Rev Lett ; 109(6): 062002, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-23006259

RESUMO

We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.

7.
Rev Med Interne ; 42(12): 862-868, 2021 Dec.
Artigo em Francês | MEDLINE | ID: mdl-34175144

RESUMO

Thrombin generation assay (TGA) is a useful tool to evaluate the initiation, propagation and inhibition of coagulation. TGA is a global test that is used to assess hemorrhagic risk in hemophilia patients, but it can also be used to study hypercoagulable states. The interest of TGA is to screen for cardiovascular risk, which is regularly associated with autoimmune disease (AID) such as antiphospholipid syndrome. Indeed, TGA has been used to evaluate hypercoagulability in patients with antiphospholipid syndrome treated with rivaroxaban versus warfarin. In other AIDs without thrombotic events, TGA measurement is elevated, mainly in rheumatoid arthritis (RA), systemic lupus erythematosus and Behçet's disease. These findings in RA are correlated with the inflammatory activity of the disease. In systemic lupus erythematosus and Behçet's disease, TGA appears to reflect disease activity. In conclusion, TGA remains relatively under used in the clinical evaluation of AID, but it could play a greater role in the evaluation of certain potentially thrombogenic treatments in AID. Finally, TGA helps measuring AID activity, due to the clearlink between coagulation and inflammation, despite some limitations of interpretation mainly due to a lack of standardization.


Assuntos
Síndrome Antifosfolipídica , Doenças Autoimunes , Síndrome Antifosfolipídica/diagnóstico , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/epidemiologia , Coagulação Sanguínea , Humanos , Rivaroxabana , Trombina
8.
J Med Vasc ; 46(4): 163-170, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34238510

RESUMO

INTRODUCTION: The COVID-19 pandemic is associated with a high incidence of venous thromboembolism questioning the utility of a systematic screening for deep venous thrombosis (DVT) in hospitalised patients. METHODS: In this prospective bicentric controlled study, 4-point ultrasound using a pocket device was used to screen for DVT, in patients with SARS-CoV-2 infection and controls admitted for acute medical illness not related to COVID-19 hospitalised in general ward, in order to assess the utility of a routine screening and to estimate the prevalence of VTE among those patients. RESULTS: Between April and May 2020, 135 patients were screened, 69 in the COVID+ group and 66 in the control one. There was no significant difference in the rate of proximal DVT between the two groups (2.2% vs. 1.5%; P=0.52), despite the high rate of PE diagnosed among COVID-19 infected patients (10.1% vs. 1.5%, P=0.063). No isolated DVT was detected, 37.5% of PE was associated with DVT. Mortality (7.2% vs. 1.5%) was not different (P=0.21) between COVID-19 patients and controls. CONCLUSION: The systematic screening for proximal DVT was not found to be relevant among COVID-19 patients hospitalized in general ward despite the increase of VTE among this population. Further studies are needed to confirm the hypothesis of a local pulmonary thrombosis which may lead to new therapeutic targets.


Assuntos
COVID-19/epidemiologia , Programas de Triagem Diagnóstica , Hospitalização , Embolia Pulmonar/diagnóstico por imagem , Ultrassonografia , Trombose Venosa/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , COVID-19/mortalidade , Estudos de Casos e Controles , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Embolia Pulmonar/epidemiologia , Medição de Risco , Fatores de Risco , Procedimentos Desnecessários , Trombose Venosa/epidemiologia
9.
Phys Rev Lett ; 104(9): 091101, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20366976

RESUMO

We describe the measurement of the depth of maximum, X{max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10;{18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{-21}{+35}) g/cm{2}/decade below 10{18.24+/-0.05} eV, and (24+/-3) g/cm{2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

10.
Rev Med Interne ; 41(5): 339-342, 2020 May.
Artigo em Francês | MEDLINE | ID: mdl-31882188

RESUMO

INTRODUCTION: Hemolacria is a rare hemorrhagic syndrome characterized by bloody tears. The most common etiologies are inflammation, infection or laceration. However, other rarer diseases may also cause this clinical manifestation. CASE REPORT: We describe the case of a 14-year-old male patient hospitalized for hemolacria. A history of von Willebrand disease was present in his family, diagnosed in his mother and sister, but absent in our patient. A vitamin C dosage was obtained in our patient and revealed scurvy consecutive to malnutrition. After having excluded other bleeding symptoms like bruises we retained vitamin C deficiency as the etiology of the hemorrhagic syndrome. CONCLUSION: Bloody tears are a rare clinical manifestation and the etiology may be difficult to determine. Bloody tears are a rare clinical manifestation of hemorrhagic syndrome. To determine the underlying etiology, screening should consider all possible causes including the rarest.


Assuntos
Hemorragia Ocular/diagnóstico , Escorbuto/diagnóstico , Lágrimas , Adolescente , Diagnóstico Diferencial , Hemorragia Ocular/etiologia , Humanos , Masculino , Desnutrição/complicações , Desnutrição/diagnóstico , Escorbuto/etiologia , Síndrome
11.
Comput Softw Big Sci ; 4(1): 7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33385105

RESUMO

We describe a fully GPU-based implementation of the first level trigger for the upgrade of the LHCb detector, due to start data taking in 2021. We demonstrate that our implementation, named Allen, can process the 40 Tbit/s data rate of the upgraded LHCb detector and perform a wide variety of pattern recognition tasks. These include finding the trajectories of charged particles, finding proton-proton collision points, identifying particles as hadrons or muons, and finding the displaced decay vertices of long-lived particles. We further demonstrate that Allen can be implemented in around 500 scientific or consumer GPU cards, that it is not I/O bound, and can be operated at the full LHC collision rate of 30 MHz. Allen is the first complete high-throughput GPU trigger proposed for a HEP experiment.

12.
Rev Med Interne ; 40(6): 351-354, 2019 Jun.
Artigo em Francês | MEDLINE | ID: mdl-30905593

RESUMO

PURPOSE: Antiphospholipid syndrome (APS) is a clinico-biological syndrome, which associates vascular injury and persisting antiphospholipid antibodies (aPL). Patients with clinical symptoms of APS but without aPL are defined as "seronegative APS" (SNAPS). The aim of this study was to evaluate antiphosphatidylethanolamine antibody (aPE) investigation in patients with SNAPS suspicion. METHODS: This retrospective study was conducted in patients with SNAPS suspicion. A homemade enzyme-linked immunosorbent assay (ELISA) was used to search for aPE. The results of this homemade method were compared with those from a global screening ELISA. RESULTS: Two hundred twenty-eight patients with SNAPS suspicion were included. Among them, 58.3% had a thrombotic event. The homemade ELISA found positive persisting aPE in 23 patients (10%): 15 with a thrombotic event, 6 with obstetrical morbidity and 2 with a combined event. The global screening ELISA was positive in only 11 of these 23 patients (47.8%). CONCLUSION: These results suggest the implication of aPE in SNAPS.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/imunologia , Fosfatidiletanolaminas/imunologia , Adulto , Idoso , Síndrome Antifosfolipídica/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Eur Phys J C Part Fields ; 75(6): 269, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26120280

RESUMO

Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.

14.
Phys Rev Lett ; 100(21): 211101, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18518595

RESUMO

The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV.

15.
Phys Rev Lett ; 101(6): 061101, 2008 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-18764444

RESUMO

The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.

16.
Science ; 318(5852): 938-43, 2007 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-17991855

RESUMO

Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above 6 x 10(19) electron volts and the positions of active galactic nuclei (AGN) lying within approximately 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest-energy particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.

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