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We demonstrate a catalytic base-free strategy for the selective oxidation of microcrystalline cellulose to oxalic acid (OA) by combining low frequency ultrasound as an unconventional activation technique and Au/Fe2O3 as a catalyst.

International audience; Hydrazine is a chemical of outmost importance in our society, either for organic synthesis or energy purpose. The direct conversion of NH3 to hydrazine is highly appealing but it remains a very difficult task because the degradation of hydrazine is thermodynamically more feasible than the cleavage of the N-H bond of NH3. As a result, any catalyst capable of activating NH3 will thus unavoidably decompose N2H4. Here we show that cavitation bubbles, created by ultrasonic irradiation of aqueous NH3 at a high frequency, act as micro-reactors to activate and convert NH3 to NH species, without assistance of any catalyst, yielding hydrazine at the bubble-liquid interface. The compartmentation of in situ produced hydrazine in the bulk solution, which is maintained close to 30°C, advantageously prevents its thermal degradation, a recurrent problem faced by previous technologies. This work also points towards a path to scavenge •OH radicals by adjusting the NH3 concentration.

Objectives Idiopathic inflammatory myopathies are mainly defined by inflammatory infiltrates within the muscle (lymphocytes and macrophages). Eosinophil muscle infiltration has been described in idiopathic eosinophilic myositis (IEM) and rarely in EF. This study aimed to further delineate the nosological frame of idiopathic eosinophil muscle infiltration through the exhaustive analysis of IEM and EF patients. Methods This multicentre retrospective case series included IEM patients diagnosed between 2000 and 2022. IEM inclusion criteria were eosinophilic muscle infiltration with myositis pathological features, after the exclusion of differential diagnoses. An additional group of EF patients diagnosed between 2016 and 2022 was constituted. Inclusion criteria were an EF diagnosis and fascia thickening with inflammatory infiltrate. Results A total of 20 IEM cases and 10 EF cases were included. The median (interquartile range) age at diagnosis was 65 (49–70) years; there were 18 males. Data analysis delineated four subgroups: focal EM (FEM, n = 3), diffuse EM (DEM, n = 6), eosinophilic myofasciitis (EMF, n = 11) and EF (n = 10). FEM represented a limited and benign form of myositis. DEM cases presented objective muscle impairment with eosinophilic muscle infiltration. EMF patients presented subjective muscle impairment (myalgia, 55%), fasciitis (on histology and/or imaging), eosinophilic muscle infiltration and frequent hypereosinophilia (55%). EF patients presented myalgia (50%), muscle lesions on histology with fascia-restricted inflammatory infiltrates with (60%) or without (40%) eosinophils. Conclusions The analysis of IEM and EF patient characteristics delineates four subgroups (FEM, DEM, EMF and EF) in terms of clinical, laboratory, imaging, pathological and outcome specificities, and proposes an adapted diagnostic and care management approach.

International audience; The current generation of networks empowers the use of programmable switches whose behaviour can be defined using languages like P4. Nevertheless, these languages do not support network-wide deployment of stateful real-value functions. This paper presents NetREC, an extension of RMT programmable data planes designed to enable stateful real-value functions computation across multiple switches. NetREC first decomposes the real-value functions into a dependency graph of elementary operations that are distributed among the network. This distribution is carried out by dynamically generating and solving an integer linear program. We deploy a prototype of NetREC on a network of Tofino switches and demonstrate its capability of computing recursive real-value functions like exponential weighted moving average.

International audience

International audience; Alkyl amines represent an important class of chemicals with multiple applications in our daily life. Among the different routes to alkyl amines, the catalytic hydroamination of alkenes with amines is of high interest mainly because it occurs in a 100% atom-economical fashion. To circumvent thermodynamic limitations, activated alkenes or activated amines are essentially employed in such reactions. To date, the catalytic hydroamination of cheap and abundant non-activated (linear) alkenes with ammonia, the simplest amine, remains an unsolved reaction by catalysis. This tutorial review covers the advances reported so far in the intermolecular hydroamination of non-activated linear alkenes with simple alkyl amines, with special interest in ammonia. Focusing on thermodynamics, catalysis and emerging technologies, we aim at providing new perspectives to look at this challenging reaction from a different point of view. In particular, we highlight that the generation of amino radicals from NH3 using “physics activation” is a potential source of inspiration to (i) reduce energy barriers and (ii) reverse the regioselectivity to complete anti-Markovnikov addition

Glycerol, which bears green, low-cost, and good miscibility features, provides a variety of solvent portfolios to satisfy the complex market demands. Owing to its abundant feedstock and unique properties, glycerol is a good candidate in catalysis, high-value-added chemical conversion, and solvents. It can also be used as an energy transportation medium attributed to its high boiling temperature, promising thermal stability, and fertile hydrogen bond. Despite the great potential of glycerol in energy transportation, a review paper that summarizes and discusses its recent advances is blank to date. In this review paper, recent advances in the utilization of glycerol and glycerol-based mixture solvent systems in energy transportation were summarized. Thermophysical properties of glycerol-containing fluids, including their performance in various heat transfer occasions, and principles of related energy transportation were comprehensively introduced and discussed. Applications of these fluids in industrial processes were also discussed systematically. Furthermore, advantages and drawbacks of glycerol in energy transportation were concluded. It opens an important avenue to alleviate the backlog of glycerol production by means of valuable applications.

Acting as a C1 building block, formaldehyde is of great significance in organic synthesis. It is also a key feedstock in several industries, such as resins, polymers, adhesives, and paints. Multicomponent reactions (MCRs) have emerged as applicable tools in organic reactions because efficient MCRs allow the creation of several chemical bonds in one sequence without labor-consuming reaction condition optimization and work-up procedures, thus minimizing waste production, cost, and labor consumption. In this review, we mainly focus on the recent advances in the contribution of formaldehyde, which was herein used as a versatile C1 building block to produce either acyclic or heterocyclic molecules via MCRs with the potential to be more sustainable than lengthier alternatives and used as a divergent chemical thanks to its excellent reactivity, flexibility, and hydrophilicity.

International audience; Through selected examples, we report here that ultrasound is capable of assisting a solid catalyst in various reactions. Beside improvement of heat and mass transfer induced by the implosion of cavitation bubbles, we show that a synergistic effect can occur between catalysis and ultrasound. In particular, the physical and chemical effects locally exerted on a catalytic surface upon implosion of cavitation bubbles can oxidize metal ions, provide energy to the catalyst/reaction, in situ activate or create catalytic sites and even prevent the catalyst from deactivation. The impact of ultrasound on solid catalyst structures, which may positively or negatively impact the performances of catalysts, is also discussed.

International audience; The production of amine intermediates from biomass is capturing increasing attention. Herein we report simple and efficient preparation of l furan-derived amines (for instance 1-(furan-2-yl)-4-methylpentan-2-amine) with high yield (up to 95%) from (E)-1-(furan-2-yl)-5-methylhex-1-en-3-one. The catalyst used was Ru/C and it was recyclable up to 4th cycle. To further realize cost-efficiency, one-reactor tandem concept was attempted. To this aim direct reaction from furfural was investigated. A high yield (74%) towards 1-(furan-2-yl)-4-methylpentan-2-amine could be achieved starting directly from furfural in the presence of methylisobutyl ketone, NH3, H2 and Ru/C catalyst.

Obesity triggers skeletal muscle physio-pathological alterations. However, the crosstalk between adipose tissue and myogenic cells remains poorly understood during obesity. We identified NID-1 among the adipose tissue secreted factors impairing myogenic potential of human myoblasts and murine muscle stem cells in vitro. Mice under High Fat Diet (HFD) displayed increased NID-1 expression in the skeletal muscle endomysium associated with intramuscular fat adipose tissue expansion and compromised muscle stem cell function. We show that NID-1 is highly secreted by skeletal muscle fibro-adipogenic/mesenchymal progenitors (FAPs) during obesity. We demonstrate that increased muscle NID-1 impairs muscle stem cells proliferation and primes the fibrogenic differentiation of FAPs, giving rise to an excessive deposition of extracellular matrix. Finally, we propose a model in which obesity leads to skeletal muscle extracellular matrix remodeling by FAPs, mediating the alteration of myogenic function by adipose tissue and highlighting the key role of NID-1 in the crosstalk between adipose tissue and skeletal muscle.

Phenotyping intramuscular immune cells is essential for the characterization of dysimmune/inflammatory myopathies (DIM). Flow cytometry (FC) is the most reliable technique for analyzing leukocyte subpopulations and evaluating their activation levels. We developed a purely mechanical protocol for extracting cells from muscle tissue allowing us to preserve cell surface epitopes and determined its applicability to experimental pathology in mice and myopathological diagnosis in human. Skeletal muscle regeneration in mice was associated with a transient enrichment of macrophages (CD11bhighGr-1+), myeloid dendritic cells (CD3−C8+CD11bhigh), CD8+ T cells (CD3+C8+), and NK cells (CD3− CD11bhighNKp46+). In murine models of inherited muscle dystrophies, leukocytes represented 23%–84% of intramuscular mononuclear cells, with a percentage of CD8+ T cells (4%–17%) mirroring that of all CD45+ cells, while MDCs remained a minority. In human 16 samples (DIM: n = 9; nonimmune conditions: n = 7), DIM was associated with intramuscular recruitment of CD8+ T cells, but not CD4+ T cells and NK cells. FC allowed concomitant quantification of HLA-DR, CD25, CD38, and CD57 activation/differentiation biomarkers and showed increased activation levels of CD4+ and CD8+ T cells in DIM. In conclusion, FC is an appropriate method for quantifying intramuscular leukocyte subpopulations and analyzing their activation states.

BackgroundDuchenne muscular dystrophy (DMD) is a progressive muscle degenerative disorder, culminating in a complete loss of ambulation, hypertrophic cardiomyopathy and a fatal cardiorespiratory failure.Necroptosis is the form of necrosis that is dependent upon the receptor-interacting protein kinase (RIPK) 3; it is involved in several inflammatory and neurodegenerative conditions. We previously identified RIPK3 as a key player in the acute myonecrosis affecting the hindlimb muscles of the dystrophic mouse model, mdx. Whether necroptosis also mediates respiratory and heart disorders in DMD is currently unknown.MethodsEvidence of activation of the necroptotic axis was examined in dystrophic tissues from Golden retriever muscular dystrophy (GRMD) dogs and R-DMDdel52 rats. A functional assessment of the involvement of necroptosis in dystrophic animals was performed on mdx mice that were genetically depleted for RIPK3. Dystrophic mice aged from 12 to 18 months were analyzed by histology and molecular biology to compare the phenotype of muscles from mdxRipk3+/+and mdxRipk3-/-mice. Heart function was also examined by echocardiography in 40-week-old mice.ResultsQuantification ofRIPK3transcripts in sartorius and biceps femoris muscles from GRMD dogs positively correlated to myonecrosis levels (r=0.81; p=0.0076).RIPK3was also found elevated in the diaphragm (p=0of Ripk1(p=0.007) andRipk3(p=0.008), indicating primed activation of the necroptotic pathway in the dystrophic heart. MdxRipk3-/-mice displayed decreased compensatory hypertrophy of the heart (p=0.014), and echocardiography showed a 19% increase in the relative wall thickness (pRipk3-/-mice presented no evidence of a regenerative default or sarcopenia in skeletal muscles, moreover around 50% less affected by fibrosis (pConclusionsOur data provide evidence of the activation of the necroptotic pathway in degenerative tissues from dystrophic animal models, including the diaphragm and the heart. The genetic inhibition of necroptosis in dystrophic mice improves both cardiac function and histological features of muscles, suggesting that prevention of necroptosis is susceptible to providing multiorgan beneficial effects for DMD.

Additional file 1. Fig. S1 Myofibre CSA of the diaphragm and morphological evaluation of TA muscle. Fig. S2 Inflammatory cytokine evaluation and fibre type switching in R-DMDdel52 rats. Fig. S3 COMP expression in heart and diaphragm