Axl and MerTK regulate synovial inflammation and are modulated by IL-6 inhibition in rheumatoid arthritis.

The TAM tyrosine kinases, Axl and MerTK, play an important role in rheumatoid arthritis (RA). Here, using a unique synovial tissue bioresource of patients with RA matched for disease stage and treatment exposure, we assessed how Axl and MerTK relate to synovial histopathology and disease activity, and their topographical expression and longitudinal modulation by targeted treatments. We show that in treatment-naive patients, high AXL levels are associated with pauci-immune histology and low disease activity and inversely correlate with the expression levels of pro-inflammatory genes. We define the location of Axl/MerTK in rheumatoid synovium using immunohistochemistry/fluorescence and digital spatial profiling and show that Axl is preferentially expressed in the lining layer. Moreover, its ectodomain, released in the synovial fluid, is associated with synovial histopathology. We also show that Toll-like-receptor 4-stimulated synovial fibroblasts from patients with RA modulate MerTK shedding by macrophages. Lastly, Axl/MerTK synovial expression is influenced by disease stage and therapeutic intervention, notably by IL-6 inhibition. These findings suggest that Axl/MerTK are a dynamic axis modulated by synovial cellular features, disease stage and treatment

The CECAM Electronic Structure Library and the modular software development paradigm

First-principles electronic structure calculations are very widely used thanks to the many successful software packages available. Their traditional coding paradigm is monolithic, i.e., regardless of how modular its internal structure may be, the code is built independently from others, from the compiler up, with the exception of linear-algebra and message-passing libraries. This model has been quite successful for decades. The rapid progress in methodology, however, has resulted in an ever increasing complexity of those programs, which implies a growing amount of replication in coding and in the recurrent re-engineering needed to adapt to evolving hardware architecture. The Electronic Structure Library (\esl) was initiated by CECAM (European Centre for Atomic and Molecular Calculations) to catalyze a paradigm shift away from the monolithic model and promote modularization, with the ambition to extract common tasks from electronic structure programs and redesign them as free, open-source libraries. They include ``heavy-duty'' ones with a high degree of parallelisation, and potential for adaptation to novel hardware within them, thereby separating the sophisticated computer science aspects of performance optimization and re-engineering from the computational science done by scientists when implementing new ideas. It is a community effort, undertaken by developers of various successful codes, now facing the challenges arising in the new model. This modular paradigm will improve overall coding efficiency and enable specialists (computer scientists or computational scientists) to use their skills more effectively. It will lead to a more sustainable and dynamic evolution of software as well as lower barriers to entry for new developers

Single artificial atoms in silicon emitting at telecom wavelengths

Given its unrivaled potential of integration and scalability, silicon is likely to become a key platform for large-scale quantum technologies. Individual electron-encoded artificial atoms either formed by impurities or quantum dots have emerged as a promising solution for silicon-based integrated quantum circuits. However, single qubits featuring an optical interface needed for large-distance exchange of information have not yet been isolated in such a prevailing semiconductor. Here we show the isolation of single optically-active point defects in a commercial silicon-on-insulator wafer implanted with carbon atoms. These artificial atoms exhibit a bright, linearly polarized single-photon emission at telecom wavelengths suitable for long-distance propagation in optical fibers. Our results demonstrate that despite its small bandgap (~ 1.1 eV) a priori unfavorable towards such observation, silicon can accommodate point defects optically isolable at single scale, like in wide-bandgap semiconductors. This work opens numerous perspectives for silicon-based quantum technologies, from integrated quantum photonics to quantum communications and metrology

Arteritis de células gigantes en Santiago de Cuba

La etiopatogénia de la arteritis de células gigantes (A.C.G) es incierta, se ha involucrado factores étnicos, climatológicos y del medio ambiente, destacándose la asociación de la enfermedad con el HLA- DR4. Estojustificaría su característica, distribución poblacional en diferentes partes del mundo. Nuestra incidencia es de 4.2 por 1000 habitantes mayores de 50 años, con predominio del sexo femenino y la raza blanca.  Como síntomas más frecuentes encontramos la cefalea y la polimialgia reumática que afecta a la mitad de los pacientes, 9 en total de un estudio prospectivo  (mayo 1998-junio  2000) en Santiago de Cuba

Hole-Cr+ nanomagnet in a semiconductor quantum dot

International audienceWe study a new diluted magnetic semiconductor system based on the spin of the ionized acceptor Cr +. We show that the negatively charged Cr + ion, an excited state of the Cr in II-VI semiconductor, can be stable when inserted in a CdTe quantum dot (QD). The Cr + attracts a heavy-hole in the QD and form a stable hole-Cr + complex. Optical probing of this system reveals a ferromagnetic coupling between heavy-holes and Cr + spins. At low temperature, the thermalization on the ground state of the hole-Cr + system with parallel spins prevents the optical recombination of the excess electron on the 3d shell of the atom. We study the dynamics of the nano-magnet formed by the hole-Cr + exchange interaction. The ferromagnetic ground states with Mz=±4 can be controlled by resonant optical pumping and a spin relaxation time in the 20 µs range is obtained at T=4.2 K. This spin memory at zero magnetic field is limited by the interaction with phonons