Gestion des antiagrégants plaquettaires et anticoagulants lors des avulsions dentaires en soin primaire (évaluation de la pratique professionnelle)

Environ 4 millions de français sont traités par antiagrégant plaquettaire, et 1% de la population française est sous anticoagulant. En médecine libérale, il est fréquent d'être interrogé par les patients sur ces traitements lorsqu'ils doivent subir une avulsion dentaire, geste de chirurgie à part entière. Des recommandations existent depuis 2 à 3 ans sur ce sujet, mais sont-elles bien appliquées ? Cette enquête-évaluation a étudié les pratiques professionnelles courantes, par le biais d'un questionaire sous forme de QCM (questions à choix multiples), soumis à des médecins généralistes et à des chirurgiens-dentistes exerçant dans le même secteur. Les recommandations ne sont pas appliquées par la majorité des praticiens interrogés. Avant une avulsion dentaire, les antiagrégants sont arrêtés pour la plupart des médecins et chirurgiens-dentistes. Pour les anticoagulants, des modifications thérapeutiques sont observées, ce qui n'est pas justifié dans ce cas de chirurgie mineure. Il existe une divergence entre les recommandations et la pratique professionnelle observée dans l'étude. Elle occasionne des désordres thérapeutiques pouvant avoir des incidences néfastes pour les patients, et présentant un surcoût en économie de santé. Aujourd'hui, en prévision d'une chirurgie dentaire simple, avec utilisation d'hémostatiques locaux, il ne faut arrêter ni les antiagrégants, ni les antivitamines-K.CLERMONT FD-BCIU-Santé (631132104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Études vers la synthèse de la célogentine C

Une première partie de cette thèse décrit une approche synthétique vers la célogentine C, molécule naturelle extraite de graines de Celosia argentea, qui présente des propriétés antimitotiques intéressantes par inhibition de la polymérisation de la tubuline. La présence de liaisons inhabituelles au sein de ce composé (entre les chaînes latérales d'une leucine, d'un tryptophane et d'une histidine) procure à cet octapeptide bicyclique une structure originale. Le fragment beta-leucine-trytophane de la célogentine C a pu être préparé de manière contrôlée par une réaction d'hydrogénation asymétrique. Une deuxième partie concerne le développement de réactions catalysées par le chlorure de fer(III). L'hydroamination de styrènes par différents nucléophiles azotés désactivés et la cyclisation de 2-alkynylanilines non-protégées en indoles (dans ce cas, en association avec le palladium) ont pu être catalysées par ce complexe de fer. Le caractère acide de Lewis du fer a également été mis à profit pour la synthèse "one-pot" de bis(indolyl)méthanes.A first part of this thesis describes an approach towards the synthesis of celogentin C, a natural compound extracted from Celosia argentea, with potent antimitotic activities. The presence of unusual bonds between the side chains of a leucine, a tryptophan and a histidine gives to this bicyclic octapeptide an original structure. The beta-leucine-tryptophan residue of celogentin C has been synthesised with high selectivities using an asymmetric hydrogenation. A second part deals with iron(III) chloride catalysed reactions. Styrenes hydroamination using various deactivated nitrogen nucleophiles and non protected 2-alkynylanilines cyclisation to indoles (in this case in presence of palladium) have been catalysed using this complex. The Lewis-acidity nature of iron(III) chloride has been further used in the one-pot synthesis of bis(indolyl)methanes.ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF

Stereocontrolled Routes to beta,beta'-disubstituted alpha-amino-acids

International audienceOwing to their significant abundance in natural products, chiral beta,beta'-disubstituted alpha-amino-acids remain an important synthetic objective. Emphasis has been focused in this review on the great diversity of enantio- and diastereo-selective methodologies to reach these highly functionalized compounds. Oldest and cutting edge synthetic methods are described in parallel to the synthesis of many relevant biologically active targets

Synthesis of the central tryptophan-leucine residue of celogentin C

International audiencehe synthesis of the central tryptophan residue of celogentin C is described featuring a Pd-catalyzed imine/enamine Heck-type reaction, a Pd-catalyzed Suzuki coupling, and an asym. Rh-catalyzed hydrogenation

Polyfunctional cotton fabrics with catalytic activity and antibacterial capacity

International audienceA novel, eco-friendly and cost-effective method involving cotton fabric (CF) coating with copper oxide and grafting of 3-chloropropyltriethoxisilane and diethanolamine resulted in a multifunctional material (CF@CuO-Si-N(OH)2). The latter exhibited catalytic activity in 4-nitrophenol (4-NP) reduction, Methylene Blue degradation and antibacterial activity. Scanning electron microscopy, energy dispersive X-ray-fluorescence, Fourier transform infrared and UV–visible spectroscopies, contact angle and thermogravimetric analysis revealed the key-role of amine grafting in changes in wettability, stability, morphological and thermal properties. 4-NP catalytic reduction was found to obey 1st-order kinetics, affording 98% conversion even after 7 successive reuses. CF@CuO-Si-N(OH)2 also exhibited appreciable antibacterial capacity against Staphylococcus epidermidis (S.epidermidis) and Escherichia coli (E. coli). These results open promising prospects for using textile fiber-based nanocomposites in diverse technological applications

Inorganic-organic-fabrics based polyester/cotton for catalytic reduction of 4-nitrophenol

International audiencePolyester/cotton (PC) fabric was functionalized with CuO dispersion followed by diethanolamine (DEA) grafting. The resulting PCCuO-DEA material was characterized, and the infrared spectrum confirmed the presence of functional groups on the surface. Scanning electron microscopy indicated that CuO insertion resulted in agglomerated particles with uniform size distribution around 50 μm. Thermogravimetric analysis evidenced a good thermal stability of PCCuO-DEA. The latter acquired new active sites at the PC surface, producing improved catalytic reduction of 4-NP into 4-aminophenol (4-AP). The kinetic studies of 4-NP reduction by sodium borohydride revealed a pseudo-first-order reaction. In presence of CuO-DEA, 4-NP was fully converted into 4-AP in less than 8 min. It was also found that PCCuO-DEA exhibits high catalytic activity even after six successive cycles, with nearly 89% conversion. The above results open an intersting avenue for developing functional textile-based catalysts, which are expected to be very useful in many technological applications

Copper oxide coated polyester fabrics with enhanced catalytic properties towards the reduction of 4-nitrophenol

International audienceA novel functional polyester fabric (PF) was successfully prepared by a facile method. PF were coated by copper oxide (CuO) followed by chemical grafting of 3-chloropropyltriethoxysilane (ClPTES) and diethanolamine (DEA). The morphology and structure of the resulting material PF@CuO–Si–N(OH)2 was characterized by X-ray diffraction, scanning electron and optical microscopy, thermogravimetry and Fourier-transformed infrared spectroscopy. The results revealed that the CuO particles were densely surrounded PF, and the covalent surface-grafting of ClPTES and DEA within PF was confirmed. It was also demonstrated that CuO/ClPTES/DEA addition generated new functional sites at the PF surface, improving the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The prepared PF@CuO–Si–N(OH)2 exhibited high catalytic activity with appreciable cycling stability for the reduction of 4-NP to 4-AP, even after six successive cycles with nearly 90% conversion. Hence, it may be conclude that the catalytic activity and stability of this catalyst allows envisaging great prospect for large scale reduction of 4-NP

Chan–Lam–Evans Coupling of Cbz-Protected Histidines

International audienceDirect functionalization of protected histidines with arylboronic acids is described under Chan–Lam–Evans conditions to give the corresponding N(τ)-arylhistidines in moderate to good yields (12 examples, up to 83% yield) under mild conditions

Immune Thrombocytopenic Purpura in Patients with COVID-19

We described three COVID-19-infected patients with profound immune thrombocytopenia causing haemorrhagic mucocutaneous complications. We conclude that an immune mechanism was responsible as common causes were excluded. Since corticoids were considered harmful in the circumstances, the patients were successfully treated with intravenous immunoglobulins without later relapse