512 research outputs found
Nouvelles voies de synthèse stéréosélectives de monofluoroalcènes
Parmi les différentes fonctionnalités contenant un atome de fluor, les fluoroalcènes sont des motifs particulièrement intéressants, possédant de nombreuses applications dans le domaine de la chimie médicinale, des sciences des matériaux, et en synthèse organique. Pourtant, il existe peu de méthodes efficaces pour la synthèse stereoselective de ces molécules, et certaines classes de monofluoroalcènes sont encore difficiles d'accès avec les stratégies actuelles. Le sujet de cette thèse porte donc sur le développement de nouvelles voies de synthèse stéréosélectives de monofluoroalcènes diversement substitués. Les propriétés de l'atome de fluor, et leurs effets sur le profil pharmacologique de molécules bioactives (lipophilie, solubilité, stabilité métabolique, etc.), seront exposés dans le premier chapitre de cette thèse. Des travaux exploratoires sur la préparation d'alcynes fluorés seront ensuite présentés dans le chapitre 2 ; ils ont mené à la découverte de la réactivité particulière des β, β-difluorostyrènes silylés vis-à-vis de certains nucléophiles (organolithiens, hydrure). Les β, β-difluorostyrènes silylés ont alors pu être utilisés comme précurseurs communs pour la synthèse stereoselective de monofluoroalcènes tétrasubstitués (chapitre 3), trisubstitués (chapitre 4), et disubstitués (chapitre 5). Pour terminer, ces nouvelles méthodologies ont été appliquées à la synthèse de composés bioactifs (chapitres 3 et 4)
Tri- and difluoromethoxylated N-based heterocycles − Synthesis and insecticidal activity of novel F3CO- and F2HCO-analogues of Imidacloprid and Thiacloprid
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Impact of exposure of methicillin-resistant Staphylococcus aureus to polyhexanide in vitro and in vivo.
Staphylococcus aureus (MRSA) resistant to decolonization agents such as mupirocin and chlorhexidine increase the need to develop alternative decolonization molecules. The absence of reported adverse reactions and bacterial resistance to polyhexanide makes it an excellent choice as topical antiseptic. In the present study we evaluated the in vitro and in vivo capacity to generate strains with reduced polyhexanide susceptibility and cross-resistance with chlorhexidine and/or antibiotics currently used in clinic. Here we report the in vitro emergence of reduced-susceptibility to polyhexanide by prolonged-stepwise exposure to low concentrations in broth culture. Reduced susceptibility to polyhexanide was associated with genomic changes in the mprF and purR genes, and with concomitant decreased susceptibility to daptomycin and other cell-wall active antibiotics. However, the in vitro emergence of reduced-susceptibility to polyhexanide did not result in cross-resistance to chlorhexidine antiseptic. During in vivo polyhexanide clinical decolonization treatment, neither polyhexanide reduced-susceptibility nor chlorhexidine cross-resistance were observed. Together, these observations suggest that polyhexanide could be used safely for decolonisation of carriers of chlorhexidine-resistant S. aureus strains but highlight the need for careful use of polyhexanide at low antiseptic concentrations
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Is virtual reality effective to teach prevention of surgical site infections in the operating room? study protocol for a randomised controlled multicentre trial entitled VIP Room study
INTRODUCTION: Some surgical site infections (SSI) could be prevented by following adequate infection prevention and control (IPC) measures. Poor compliance with IPC measures often occurs due to knowledge gaps and insufficient education of healthcare professionals. The education and training of SSI preventive measures does not usually take place in the operating room (OR), due to safety, and organisational and logistic issues. The proposed study aims to compare virtual reality (VR) as a tool for medical students to learn the SSI prevention measures and adequate behaviours (eg, limit movements…) in the OR, to conventional teaching.
METHODS AND ANALYSIS: This protocol describes a randomised controlled multicentre trial comparing an educational intervention based on VR simulation to routine education. This multicentre study will be performed in three universities: Grenoble Alpes University (France), Imperial College London (UK) and University of Heidelberg (Germany). Third-year medical students of each university will be randomised in two groups. The students randomised in the intervention group will follow VR teaching. The students randomised in the control group will follow a conventional education programme. Primary outcome will be the difference between scores obtained at the IPC exam at the end of the year between the two groups. The written exam will be the same in the three countries. Secondary outcomes will be satisfaction and students' progression for the VR group. The data will be analysed with intention-to-treat and per protocol.
ETHICS AND DISSEMINATION: This study has been approved by the Medical Education Ethics Committee of the London Imperial College (MEEC1920-172), by the Ethical Committee for the Research of Grenoble Alpes University (CER Grenoble Alpes-Avis-2019-099-24-2) and by the Ethics Committee of the Medical Faculty of Heidelberg University (S-765/2019). Results will be published in peer-reviewed medical journals, communicated to participants, general public and all relevant stakeholders
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