94 research outputs found
Humanized anti-interleukin-6-receptor antibody (tocilizumab) monotherapy is more effective in slowing radiographic progression in patients with rheumatoid arthritis at high baseline risk for structural damage evaluated with levels of biomarkers, radiography, and BMI: data from the SAMURAI study
Our aim was to assess the ability of tocilizumab monotherapy to reduce progressive structural joint damage in rheumatoid arthritis patients at high risk of progression. This study was a subanalysis from a prospective 1-year, multicenter, X-ray-reader-blinded, randomized controlled trial of tocilizumab [Study of Active Controlled Monotherapy Used for Rheumatoid Arthritis, an IL-6 Inhibitor (SAMURAI) trial]. All patients were categorized into two or three groups according to four independent predictive markers for progressive joint damage [urinary C-terminal crosslinking telopeptide (uCTX-II), urinary pyridinoline/deoxypyridinoline (uPYD/DPD) ratio, body mass index (BMI), and joint-space narrowing (JSN) score at baseline]. One-year progression of joint destruction was assessed in high-risk versus low-risk groups receiving tocilizumab monotherapy and compared with patients receiving conventional disease-modifying antirheumatic drugs (DMARDs) (n = 157 and 145, respectively). In patients at high risk of progression of erosion as estimated by high uCTX-II, uPYD/DPD, or low BMI, and at high risk of progression of JSN as estimated by low BMI or high JSN score, the 52-week changes in radiological erosion and JSN, respectively, were significantly less in patients treated with tocilizumab monotherapy compared with those receiving DMARDs for each type of risk factor. In patients at low risk, those receiving tocilizumab also progressed less than those on DMARDs, although the difference did not reach statistical significance. Tocilizumab monotherapy is more effective in reducing radiological progression in patients presenting with risk factors for rapid progression than in low-risk patients. Patients at high risk for progression may benefit more from tocilizumab treatment
MXene Supported Cobalt Layered Double Hydroxide Nanocrystals: Facile Synthesis Route for a Synergistic Oxygen Evolution Reaction Electrocatalyst
International audienceThe development of reliable electrolyzers is closely related to the development of a cost-effective highly active and stable electrocatalysts for the oxygen evolution reaction (OER). Herein, a simple method is used to synthesize a non-noble metal-based electrocatalyst for OER by synergistically coupling a catalytically active cobalt layered double hydroxide (Co-LDH) with a highly electrically conducting 2D transition metal carbide, Ti3C2Tx MXene. The synergy between these two bidimensional materials (Co-LDH and Ti3C2Tx), evidenced by coupling electron energy loss spectroscopy and density functional theory simulations, results in superior electrocatalytic properties and makes possible having an excellent and stable oxygen evolution electrocatalyst. Moreover, the oxidative-sensitive MXene structure is preserved during the synthesis of the composite and the formation of a well recovering Co-LDH phase avoids the irreversible oxidation of MXene at high potential values, which may affect its conductivity. With an overpotential of approximate to 330 mV at a current density of 10 mA cm(-2) the catalyst exhibits a higher catalytic activity toward OER than commercial IrO2 catalysts
Chemical ordering in bimetallic FeCo nanoparticles: From a direct chemical synthesis to application as efficient high-frequency magnetic material
Single-crystalline FeCo nanoparticles with tunable size and shape were prepared by co-decomposing two metal-amide precursors under mild conditions. The nature of the ligands introduced in this organometallic synthesis drastically affects the reactivity of the precursors and, thus, the chemical distribution within the nanoparticles. The presence of the B2 short-range order was evidenced in FeCo nanoparticles prepared in the presence of HDAHCl ligands, combining 57Fe Mössbauer, zero-field 59Co ferromagnetic nuclear resonance (FNR), and X-ray diffraction studies. This is the first time that the B2 structure is directly formed during synthesis without the need of any annealing step. The as-prepared nanoparticles exhibit magnetic properties comparable with the ones for the bulk (Ms = 226 Am2·kg¿1). Composite magnetic materials prepared from these FeCo nanoparticles led to a successful proof-of-concept of the integration on inductor-based filters (27% enhancement of the inductance value at 100 MHz).This work was performed in the frame of TOURS 2015, and the project was supported by the French “Programme de l’économie numérique des Investissements d’Avenir”. We gratefully acknowledge the International Associated Laboratory (LIA)-M2OZART for financial support. Some of the HR-STEM and EELS studies were conducted at the Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, Universidad de Zaragoza, Spain. R.A. gratefully acknowledges the support from the Spanish Ministry of Economy and Competitiveness (MINECO) through project MAT2016-79776-P (AEF/FEDER. UE). In IPCMS Strasbourg, the work was supported by the CNRS LIA “NANOFUNC” and the LABEX NIE (no. ANR-11-LABX-0058_NIE)
Developing a toolkit for the assessment and monitoring of musculoskeletal ageing
The complexities and heterogeneity of the ageing process have slowed the development of consensus on appropriate biomarkers of healthy ageing. The Medical Research Council–Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA) is a collaboration between researchers and clinicians at the Universities of Liverpool, Sheffield and Newcastle. One of CIMA’s objectives is to ‘Identify and share optimal techniques and approaches to monitor age-related changes in all musculoskeletal tissues, and to provide an integrated assessment of musculoskeletal function’—in other words to develop a toolkit for assessing musculoskeletal ageing. This toolkit is envisaged as an instrument that can be used to characterise and quantify musculoskeletal function during ‘normal’ ageing, lend itself to use in large-scale, internationally important cohorts, and provide a set of biomarker outcome measures for epidemiological and intervention studies designed to enhance healthy musculoskeletal ageing. Such potential biomarkers include: biochemical measurements in biofluids or tissue samples, in vivo measurements of body composition, imaging of structural and physical properties, and functional tests. This review assesses candidate biomarkers of musculoskeletal ageing under these four headings, details their biological bases, strengths and limitations, and makes practical recommendations for their use. In addition, we identify gaps in the evidence base and priorities for further research on biomarkers of musculoskeletal ageing
Periostin deficiency increases bone damage and impairs injury response to fatigue loading in adult mice.
Bone damage removal and callus formation in response to fatigue loading are essential to prevent fractures. Periostin (Postn) is a matricellular protein that mediates adaptive response of cortical bone to loading. Whether and how periostin influences damage and the injury response to fatigue remains unknown. We investigated the skeletal response of Postn(-/-) and Postn(+/+) mice after fatigue stimulus by axial compression of their tibia. In Postn(+/+) mice, cracks number and surface (CsNb, CsS) increased 1h after fatigue, with a decrease in strength compared to non-fatigued tibia. At 15 days, CsNb had started to decline, while CtTV and CtBV increased in fatigued vs non-fatigued tibia, reflecting a woven bone response that was present in 75% of the fatigued bones. Cortical porosity and remodelling also prominently increased in the fatigued tibia of Postn(+/+) mice. At 30 days, paralleling a continuous removal of cortical damage, strength of the fatigued tibia was similar to the non-fatigue tibia. In Postn(-/-) mice, cracks were detectable even in the absence of fatigue, while the amount of collagen crosslinks and tissue hardness was decreased compared to Postn(+/+). Fatigue significantly increased CsNb and CsS in Postn(-/-), but was not associated with changes in CtTV and CtBV, as only 16% of the fatigued bones formed some woven bone. Cortical porosity and remodelling did not increase either after fatigue in Postn(-/-), and the level of damage remained high even after 30 days. As a result, strength remained compromised in Postn(-/-) mice. Contrary to Postn(+/+), which osteocytic lacunae showed a change in the degree of anisotropy (DA) after fatigue, Postn(-/-) showed no DA change. Hence periostin appears to influence bone materials properties, damage accumulation and repair, including local modeling/remodeling processes in response to fatigue. These observations suggest that the level of periostin expression could influence the propensity to fatigue fractures
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