In order to describe the clinical features and the epidemiologic findings of 1,383 patients hospitalized in France for acute or chronic Q fever, we conducted a retrospective analysis based on 74,702 sera tested in our diagnostic center, National Reference Center and World Health Organization Collaborative Center for Rickettsial Diseases. The physicians in charge of all patients with evidence of acute Q fever (seroconversion and/or presence of IgM) or chronic Q fever (prolonged disease and/or IgG antibody titer to phase I of Coxiella burnetii > or = 800) were asked to complete a questionnaire, which was computerized. A total of 1,070 cases of acute Q fever was recorded. Males were more frequently diagnosed, and most cases were identified in the spring. Cases were observed more frequently in patients between the ages of 30 and 69 years. We classified patients according to the different clinical forms of acute Q fever, hepatitis (40%), pneumonia and hepatitis (20%), pneumonia (17%), isolated fever (17%), meningoencephalitis (1%), myocarditis (1%), pericarditis (1%), and meningitis (0.7%). We showed for the first time, to our knowledge, that different clinical forms of acute Q fever are associated with significantly different patient status. Hepatitis occurred in younger patients, pneumonia in older and more immunocompromised patients, and isolated fever was more common in female patients. Risk factors were not specifically associated with a clinical form except meningoencephalitis and contact with animals. The prognosis was usually good except for those with myocarditis or meningoencephalitis as 13 patients died who were significantly older than others. For chronic Q fever, antibody titers to C. burnetii phase I above 800 and IgA above 50 were predictive in 94% of cases. Among 313 patients with chronic Q fever, 259 had endocarditis, mainly patients with previous valvulopathy; 25 had an infection of vascular aneurysm or prosthesis. Patients with endocarditis or vascular infection were more frequently immunocompromised and older than those with acute Q fever. Fifteen women were infected during pregnancy; they were significantly more exposed to animals and gave birth to only 5 babies, only 2 with a normal birth weight. More rare manifestations observed were chronic hepatitis (8 cases), osteoarticular infection (7 cases), and chronic pericarditis (3 cases). Nineteen patients were observed who experienced first a documented acute infection, then, due to underlying conditions, a chronic infection. To our knowledge, we report the largest series of Q fever to date. Our results indicate that Q fever is a protean disease, grossly underestimated, with some of the clinical manifestations being only recently reported, such as Q fever during pregnancy, chronic vascular infection, osteomyelitis, pericarditis, and myocarditis. Our data confirm that chronic Q fever is mainly determined by host factors and demonstrate for the first time that host factors may also play a role in the clinical expression of acute Q fever.

Objective The role for interferon (IFN)-α in systemic lupus erythematosus (SLE) pathogenesis is strongly supported by gene expression studies. The aim of this study was to improve characterization of the blood-IFN signature in adult SLE patients. Methods Consecutive patients were enrolled and followed-up prospectively. Microarray data were generated using Illumina beadchips. A modular transcriptional repertoire was employed as a framework for the analysis. Results Our repertoire of 260 modules, which consist of co-clustered gene sets, included 3 IFN-annotated modules (M1.2, M3.4 and M5.12) that were strongly up-regulated in SLE patients. A modular IFN signature (mIS) was observed in 54/62 (87%) patients or 131/157 (83%) longitudinal samples. The IFN signature was more complex than expected with each module displaying a distinct activation threshold (M1.2

Abstract-Microparticles are small vesicles playing a crucial role in cell communication by promoting prothrombotic and proinflammatory responses. However, the molecular mechanisms underlying their release are still elusive. We previously established that thrombin promoted the generation of endothelial microparticles (EMPs). In the present study, gene profiling identified TRAIL/Apo2L, a cytokine belonging to the tumor necrosis factor-␣ superfamily, as a target of thrombin. Thrombin increased the expression of cell-associated and soluble forms of TRAIL (sTRAIL) in HMEC-1 cells and human umbilical vein endothelial cells (HUVECs). Blocking TRAIL by specific antibodies or by small interfering RNA reduced both the number and the procoagulant activity of EMPs released by thrombin. Consistent with an involvement of sTRAIL in thrombin-induced EMP release, we showed that (1) exogenously added sTRAIL generated procoagulant EMPs; (2) supernatants from thrombin-stimulated endothelial cells induced EMP release by HMEC-1 cells and HUVECs, whereas those recovered from TRAIL knockdown endothelial cells displayed no effect. TRAIL/ TRAIL-R2 complex mediated EMP release by initiating the recruitment of adaptor proteins and the activation of nuclear factor B. Moreover, sTRAIL modulated intercellular adhesion molecule-1 and interleukin-8 expression induced by thrombin by a downstream pathway involving nuclear factor B activation. Our data reveal a novel mechanism controlling EMP release and identify TRAIL as a key partner in the pathway linking coagulation and inflammation elicited by thrombin. Key Words: endothelium Ⅲ vesiculation Ⅲ cell signaling Ⅲ inflammation Ⅲ coagulation Ⅲ thrombosis T hrombin is a serine protease that plays a key role in the pathogenesis of vascular diseases. It is generated at sites of vessel damage and controls the formation of a hemostatic plug. Thrombin plays a central role in the crosstalk between inflammation and coagulation by inducing the synthesis of proinflammatory cytokines that activates the coagulation cascade 1 and by impairing anticoagulant mechanisms. 2 It also exerts pleiotropic effects on endothelium. 3 Recent data from our laboratory indicated that thrombin induces the release of microparticles by endothelial cells (endothelial microparticles [EMPs]), an effect mediated by the receptor PAR-1. 4 Microparticles (MPs) are a heterogeneous population of small membrane-coated vesicles resulting from disruption of the membrane phospholipid asymmetry, leading to phosphatidylserine exposure in response to cell activation or apoptosis. Their capacity to carry surface antigens, cytoplasmic proteins, or nucleic acids from their parent cells confers to MPs a major role in cell communication by binding to their targets or facilitating cell-cell interactions. 5 In theory, all cells have the capacity to form MPs and endothelial cells generate EMPs that provide procoagulant surfaces able to trigger coagulation activation. 6 Indeed, once available at the surface of the MP, phosphatidylserine exposure pro...