Multi-stack fuel cells powering a vehicle

International audienceCurrent issues concerning global warming and fossil fuel energy shortages impose to find alternatives in order to meet the growing planet’s energy demand. The automotive sector is particularly concerned with these issues. The fuel cell seems to be a very promising technology. This article addresses a technological aspect of the integration of fuel cell on a vehicle. The chosen configuration is a multi-pack system favoring the use of several reduced power fuel cells. The energy management method is described along with the sizing and some simulation results

Symptomatic muscular sarcoidosis

International audienceObjectives To describe clinicopathologic features of muscular sarcoidosis and the associated sarcoidosis phenotype through a nationwide multicenter study. Methods Patients were included if they had histologically proven sarcoidosis and symptomatic muscular involvement confirmed by biological, imaging, or histologic examinations. Results Forty-eight patients (20 males) were studied, with a median age at muscular symptoms onset of 45 years (range 18–71). Four patterns were identified: a nodular pattern (27%); smoldering phenotype (29%); acute, subacute, or progressive myopathic type (35%); and combined myopathic and neurogenic pattern (10%). In all patterns, sarcoidosis was multivisceral with a median of 3 extramuscular organs involved (mostly lungs, lymph nodes, eyes, and skin) and a prolonged course with long-term use of corticosteroids and immunosuppressive drugs. Muscular patterns differed according to clinical presentation (myalgia, nodules, or weakness), electromyographic findings, muscular MRI, and response to sarcoidosis treatment. The myopathic and neuromuscular patterns were more severe. Conclusion This nationwide study of muscular sarcoidosis allowed the identification of 4 patterns of granulomatous myositis, which differed by phenotypes and the clinical course

The spectrum of renal involvement in patients with inflammatory myopathies

International audienceData regarding the incidence and outcome of renal involvement in patients with inflammatory myopathies (IM) remain scarce. We assessed the incidence and causes of acute kidney injury (AKI) and chronic kidney disease (CKD) in 150 patients with dermatomyositis, polymyositis, and antisynthetase syndrome followed in 3 French referral centers. Renal involvement occurred in 35 (23.3%) patients: AKI in 16 (10.7%), and CKD in 31 (20.7%) patients. The main cause of AKI was drug or myoglobinuria-induced acute tubular necrosis. Male sex, cardiovascular risk factors, cardiac involvement, and initial proteinuria \textgreater0.3 g/d were associated with the occurrence of AKI. The outcome of patients with AKI was poor: 13 (81%) progressed to CKD and 2 (12.5%) reached end-stage renal disease. In multivariate survival analysis, age at IM onset, male sex, a history of cardiovascular events, and a previous episode of AKI were associated with the risk of CKD. We also identified 14 IM patients who underwent a kidney biopsy in 10 nephrology centers. Renal pathology disclosed a wide range of renal disorders, mainly immune-complex glomerulonephritis. We identified in 5 patients a peculiar pattern of severe acute renal vascular damage consisting mainly of edematous thickening of the intima of arterioles. We found that AKI and CKD are frequent in patients with IM. Prevention of AKI is crucial in these patients, as AKI is a major contributor to their relatively high risk of CKD. A peculiar pattern of acute vascular damage is part of the spectrum of renal diseases associated with IM

High prevalence of myeloid neoplasms in adults with non–Langerhans cell histiocytosis

International audienceKey Points Some 10.1% of adults with non–Langerhans cell histiocytosis have a concomitant myeloid neoplasm with each often harboring distinct mutations. The presence of distinct kinase mutations in histiocytosis and myeloid neoplasms resulted in discordant responses to targeted therapy

High prevalence of myeloid neoplasms in adults with non–Langerhans cell histiocytosis

International audienceKey Points Some 10.1% of adults with non–Langerhans cell histiocytosis have a concomitant myeloid neoplasm with each often harboring distinct mutations. The presence of distinct kinase mutations in histiocytosis and myeloid neoplasms resulted in discordant responses to targeted therapy

Skeletal muscle provides the immunological micro-milieu for specific plasma cells in anti-synthetase syndrome-associated myositis

International audienceAbstract Anti-synthetase syndrome (ASyS)-associated myositis is a major subgroup of the idiopathic inflammatory myopathies (IIM) and is characterized by disease chronicity with musculoskeletal, dermatological and pulmonary manifestations. One of eight autoantibodies against the aminoacyl-transferase RNA synthetases (ARS) is detectable in the serum of affected patients. However, disease-specific therapeutic approaches have not yet been established. To obtain a deeper understanding of the underlying pathogenesis and to identify putative therapeutic targets, we comparatively investigated the most common forms of ASyS associated with anti-PL-7, anti-PL-12 and anti-Jo-1. Our cohort consisted of 80 ASyS patients as well as healthy controls ( n = 40), diseased controls ( n = 40) and non-diseased controls ( n = 20). We detected a reduced extent of necrosis and regeneration in muscle biopsies from PL-12 + patients compared to Jo-1 + patients, while PL-7 + patients had higher capillary dropout in biopsies of skeletal muscle. Aside from these subtle alterations, no significant differences between ASyS subgroups were observed. Interestingly, a tissue-specific subpopulation of CD138 + plasma cells and CXCL12 + /CXCL13 + CD20 + B cells common to ASyS myositis were identified. These cells were localized in the endomysium associated with alkaline phosphatase + activated mesenchymal fibroblasts and CD68 + MHC-II + CD169 + macrophages. An MHC-I + and MHC-II + MxA negative type II interferon-driven milieu of myofiber activation, topographically restricted to the perifascicular area and the adjacent perimysium, as well as perimysial clusters of T follicular helper cells defined an extra-medullary immunological niche for plasma cells and activated B cells. Consistent with this, proteomic analyses of muscle tissues from ASyS patients demonstrated alterations in antigen processing and presentation. In-depth immunological analyses of peripheral blood supported a B-cell/plasma-cell-driven pathology with a shift towards immature B cells, an increase of B-cell-related cytokines and chemokines, and activation of the complement system. We hypothesize that a B-cell-driven pathology with the presence and persistence of a specific subtype of plasma cells in the skeletal muscle is crucially involved in the self-perpetuating chronicity of ASyS myositis. This work provides the conceptual framework for the application of plasma-cell-targeting therapies in ASyS myositis