Cellular Effects of Bacterial N-3-Oxo-Dodecanoyl-L-Homoserine Lactone on the Sponge Suberites domuncula (Olivi, 1792): Insights into an Intimate Inter-Kingdom Dialogue.

International audienceSponges and bacteria have lived together in complex consortia for 700 million years. As filter feeders, sponges prey on bacteria. Nevertheless, some bacteria are associated with sponges in symbiotic relationships. To enable this association, sponges and bacteria are likely to have developed molecular communication systems. These may include molecules such as N-acyl-L-homoserine lactones, produced by Gram-negative bacteria also within sponges. In this study, we examined the role of N-3-oxododecanoyl-L-homoserine lactone (3-oxo-C12-HSL) on the expression of immune and apoptotic genes of the host sponge Suberites domuncula. This molecule seemed to inhibit the sponge innate immune system through a decrease of the expression of genes coding for proteins sensing the bacterial membrane: a Toll-Like Receptor and a Toll-like Receptor Associated Factor 6 and for an anti-bacterial perforin-like molecule. The expression of the pro-apoptotic caspase-like 3/7 gene decreased as well, whereas the level of mRNA of anti-apoptotic genes Bcl-2 Homolog Proteins did not change. Then, we demonstrated the differential expression of proteins in presence of this 3-oxo-C12-HSL using 3D sponge cell cultures. Proteins involved in the first steps of the endocytosis process were highlighted using the 2D electrophoresis protein separation and the MALDI-TOF/TOF protein characterization: α and β subunits of the lysosomal ATPase, a cognin, cofilins-related proteins and cytoskeleton proteins actin, α tubulin and α actinin. The genetic expression of some of these proteins was subsequently followed. We propose that the 3-oxo-C12-HSL may participate in the tolerance of the sponge apoptotic and immune systems towards the presence of bacteria. Besides, the sponge may sense the 3-oxo-C12-HSL as a molecular evidence of the bacterial presence and/or density in order to regulate the populations of symbiotic bacteria in the sponge. This study is the first report of a bacterial secreted molecule acting on sponge cells and regulating the symbiotic relationship

Recommendations for the pragmatic use of ultrasound in rheumatoid arthritis by the GEISPER French group

International audienceObjective: To develop recommendations for the appropriate use of ultrasound in the management of rheumatoid arthritis (RA) in routine practice based on data from the literature and of experts opinion. Methods: Based on a systematic literature review, a scientific committee decided on themes and relevant questions to draw up an initial draft of recommendations. These recommendations were submitted to a group of experts in ultrasound in rheumatic and musculoskeletal diseases using a Delphi method, which produced preliminary recommendations. These were submitted to an expanded group of ultrasound experts for relevance, comprehensibility and comprehensiveness. The level of agreement of the experts were recorded during a face-to-face meeting. Results: Following two rounds of the Delphi, a consensus was reached on three overarching principles, including definitions of joints, tendons and articular sites to be examined, and 10 recommendations. These recommendations underline the benefit of ultrasound for the diagnosis of RA in cases of inflammatory arthralgia or undifferentiated arthritis as well as in assessing the extent of initial structural and inflammatory damage. They also define the role of ultrasound during follow-up or when considering treatment reduction once clinical remission has been achieved. Lastly, they illustrate the utility of ultrasound in facilitating technical procedures. Conclusion: These 10 consensus-based recommendations should harmonize and optimize clinical practice and thus improve the management of RA patients

Equivalent wear performance of dual mobility bearing compared with standard bearing in total hip arthroplasty: in vitro study

PURPOSE: Osteolysis in total hip arthroplasty (THA) depends on polyethylene wear and dictates the survival of the prosthesis. Dual mobility in THAs, which is claimed to reduce dislocation risk, has very good long-term clinical results. However, little is known about how the liner wears in this design, compared to the standard single mobility model. METHODS: A comparative study looking at wear of a conventional ultra-high-molecular-weight polyethylene liner, using gravimetric measurement, between dual mobility implants and standard implants, was performed on a simulator in accordance with a normed protocol based on the same dimensions, environmental conditions and stresses. A linear regression test was employed. RESULTS: Under the same conditions (loading, cycles, sterilization, material and surface roughness), the gravimetric wear (for conventional polyethylene) is comparable between a standard and a dual mobility cup. This correlates to ten year follow-up results of dual mobility cup. DISCUSSION - CONCLUSION: This in vitro equivalent wear serves to confirm the very good long-term clinical results observed with dual mobility bearing, whose use should not be restricted by concerns about increased polyethylene wear

Nouveaux électrolytes pour les batteries aqueuses et organiques en flux

International audienceRôle des Batteries à flux : - stockage grande capacité et stabilité réseaux- répond aux variations journalières voire semi-hebdomadaire de la consommation électrique- limitation du parc de production électrique en répondant aux pics de consommationsEnjeux : dans la Stratégie Nationale Bas Carbone 2050, les scenarios d’électrification avec ou sans nucléaire nécessitent l’augmentation de la part de renouvelable et des moyens de stockage accrus. Principes : la capacité de la batterie est assurée par des électrolytes stockés dans des réservoirs, et qui sont amenés au niveau des électrodes par un système de pompage (flux).Objectifs : afin de substituer le vanadium utilisé dans les batteries à flux actuelles, il faut trouver des molécules organiques ayant : - un potentiel redox adapté pour délivrer une tension suffisante- une bonne stabilité électrochimique - solubles dans l’eau afin de pouvoir l’utiliser comme solvant électrolytique (coûts et risques incendies)- solubles à forte concentration pour densifier l’énergie stockée.Résultats : de nouveaux négolytes ont été synthétisés à partir de synthons biosourcés, leur diagramme électrochimique de Pourbaix modélisés, puis testés en système batterie. Valorisation : un brevet en cours d’écriture

Nouveaux électrolytes pour les batteries aqueuses et organiques en flux

National audienc

Incidence and outcomes of revision surgery after first metatarsophalangeal joint arthrodesis: Multicenter study of 158 cases

INTRODUCTION: First metatarsophalangeal (MTP1) joint arthrodesis, described as a safe and effective procedure, has complications that may require surgical revision. These complications are rarely studied. The aim of this study was to determine the incidence and outcomes of revision surgery after MT1 arthrodesis. HYPOTHESIS: The incidence of surgical revision after MTP1 arthrodesis is not insignificant; however, the outcomes are satisfactory. MATERIALS AND METHODS: In this multicenter retrospective study between January 2014 and December 2015, 190 forefoot revisions in patients who had previously undergone MTP1 arthrodesis were included by 8 surgeons. There were no exclusion criteria and all patients had at least 1 year of follow-up. Over the same period, 958 primary MTP1 arthrodesis procedures were performed. RESULTS: The mean time to revision was 4.6±10.9 years. At a mean follow-up of 20.5±7.4 months, 158 cases were available for analysis in 135 women and 20 men who had a mean age of 67.1±10.5 years. These revision procedures were carried out because of discomfort related to the hardware at the arthrodesis site (n=86, 54%), nonunion (n=22, 14%), malunion (n=13, 8%) metatarsalgia or claw toe (n=18, 11%) and first interphalangeal (IP1) joint disorders (n=13, 8%). The mean postoperative scores were 75±13.9 for the AOFAS and 65±19.6 for the SF36 total. In the nonunion cases, removal of the hardware led to better outcomes than repeating the arthrodesis procedure. Osteotomy in the malunion cases healed successfully. In the cases of IP1 osteoarthritis, secondary arthrodesis or arthroplasty led to good outcomes. DISCUSSION: Relative to published results of primary MTP1 arthrodesis, the outcomes in our series of revision MTP1 arthrodesis surgery cases are practically equivalent, thus considered acceptable. LEVEL OF EVIDENCE: IV, Retrospective study

Comparison of the efficacy of sonography, magnetic resonance imaging and conventional radiography for the detection of bone erosions in rheumatoid arthritis patients: a systematic review and meta-analysis

International audienc

Use of glucocorticoids in rheumatoid arthritis – Pratical modalities of glucocorticoid therapy: Recommendations for clinical practice based on data from the literature and expert opinion

International audienc

Indications of glucocorticoids in early arthritis and rheumatoid arthritis: Recommendations for clinical practice based on data from the literature and expert opinion.

International audienceOBJECTIVE: To develop clinical practice guidelines about the indications of glucocorticoid therapy in early arthritis and established rheumatoid arthritis, based on previously published data and on the opinions of rheumatology experts. METHODS: We used a three-step procedure. (a) A scientific committee used a Delphi procedure to select three questions about glucocorticoid indications: what is the role for glucocorticoid therapy in early arthritis? What is the role for long-term glucocorticoid therapy in established rheumatoid arthritis? What is the role for systemic glucocorticoid therapy in flares of rheumatoid arthritis? (b) Evidence providing answers to the three questions was sought in Pubmed, Embase, Cochrane, and abstracts from the annual meetings of the ACR and EULAR. (c) Based on this evidence, recommendations were developed and validated by a panel of experts. The strength of each recommendation was determined based on the level of the underlying evidence. The level of agreement among experts regarding each recommendation was measured. RESULTS: The literature search retrieved 2851 publications, of which 36 were selected based on the titles and abstracts then on the full-length articles. These 36 studies were presented to the experts as a basis for discussion. Six recommendations rated A to D were developed and validated by the experts. They dealt with the appropriateness of low- or moderate-dose glucocorticoid therapy for a limited period in early polyarthritis after advice from a specialist and in the event of active disease, in combination with disease-modifying antirheumatic drug (DMARD) therapy; the appropriateness of low-dose glucocorticoid therapy (no more than 0.1mg/kg/day) in RA if needed to achieve symptom control; and the appropriateness of oral glucocorticoid therapy (no more than 0.5mg/kg/day) for 1 to 2 weeks in polyarticular flares of RA. CONCLUSION: The six recommendations for everyday practice presented here should help to standardize and to optimize clinical practice, thereby improving the management of patients with early arthritis or RA

Primmorph cultures stimulated for 48 h with 10⁻⁶ M of <i>N</i>-3-oxododecanoyl-_L-homoserine (A) or not stimulated (B).

<p>Primmorph cultures stimulated for 48 h with 10⁻⁶ M of <i>N</i>-3-oxododecanoyl-_L-homoserine (A) or not stimulated (B).</p