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Points essentiels Les antivitamines K (AVK) restent a l’heure actuelle l’unique traitement anticoagulant utilise par voie orale a dose curative. Actuellement environ 1 % de la population francaise est traitee par AVK, essentiellement des sujets âges. Les AVK ont un risque iatrogene important et sont la premiere cause d’accidents medicamenteux du fait de leur risque hemorragique. Dans ce contexte, des recommandations de pratique clinique ont ete plusieurs fois diffusees par l’Agence francaise de securite sanitaire des produits de sante (AFSSAPS), insistant en particulier sur la necessite d’une information et d’une education des patients ayant un traitement par AVK. La gestion du traitement par AVK est delicate avec un risque de sous ou de surdosage et donc un risque de thrombose ou d’hemorragie . La zone therapeutique des AVK est etroite, la posologie est strictement individuelle avec un ajustement des doses selon l’ International normalized ratio (INR) et les interactions medicamenteuses sont nombreuses. La litterature concernant l’efficacite de l’education therapeutique chez des patients traites par AVK fondee sur des essais controles et randomises est peu fournie . Les programmes d’education ne sont pas standardises, ils sont varies et difficilement comparables. Mais des etudes ont montre l’interet d’un programme d’education therapeutique en termes de diminution du risque hemorragique et pour une meilleure stabilite du traitement. Un programme d’education therapeutique pour les personnes sous AVK a ete developpe dans le cadre du reseau Ville-Hopital des pathologies vasculaires, Granted, sur le secteur sanitaire de Grenoble . Il propose des seances individuelles pour le patient et/ou son entourage (en structure de soins ou a domicile), un suivi telephonique precoce et des reunions de groupe. Des supports et outils d’education sont utilises. Un lien est fait avec le medecin traitant qui recoit un compte rendu d’education. La demarche d’education permet d’adapter les messages educatifs aux particularites du patient et a son quotidien et d’impliquer directement le patient et/ou son entourage dans la gestion du traitement.

The structure and visible spectra of a large panel of thioindigo dyes and derivatives have been evaluated using a TD-PBE0/6-311+G(2d,p)//PBE0/6-311G(d,p) approach explicitly taking bulk solvent effects into account by means of the polarizable continuum model. The influence of the solvent characteristics, the trans-cis isomerization, and the chemical substitution on the benzene rings have been investigated. In addition, hemi-thioindigo dyes, thiazine-indigo, chromophore-like molecules, and selenoindigo have been considered. Though the relative oscillator strengths of the two allowed visible transitions in the nonplanar cis isomers are not always correctly reproduced by theory, the agreement between theoretical and experimental results is far above expectations. For the 170 cases studied, we obtained a mean unsigned error on the predicted lambda(max) limited to 6.9 nm or 0.03 eV, with only 6 (4) cases for which the difference exceeds 20 nm (0.10 eV). These errors are 1 order of magnitude smaller than what has previously been reported for indigoids. A linear correlation between the central double bond length and the lambda(max) has been established, while the bond length and vibrational frequency of the carbonyl groups do not correlate with the thioindigo color. The higher excitation energies of the cis conformers, compared to the trans structures, result from a less stabilized LUMO in the former case. Indeed, for cis thioindigo, the two electron-rich (in the excited state) carbonyl units lie close to each other.

Using the parameter-free PBE0 hybrid functional, we compute the UV/Vis spectra of a series of solvated compounds presenting a carbonyl chromophoric unit linked to a carbon- carbon double bond. It turns out that PBE0 is extremely efficient for accurately reproducing experimental values, with a mean unsigned error of 7 nm for an extended set of compounds, although no fitting or statistical treatments are performed. PBE0 has a predictive efficiency comparable to the well-known Woodward-Fieser empirical formula, and can therefore be used to extend these rules without requiring additional experimental results. Consequently, the UV/Vis spectra of several compounds that have not yet been synthesized are predicted. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem 106: 1853-1859, 2006

The relative modifications induced in the structure of perfluorodiethyl ether (CF3CF2)2O and perfluoroisopropyl methyl ether CF3OCF(CF3)2 by oxygen and fluorine protonation are studied at the RHF level with the 3–21G basis and correlated with their proton affinities and dissociation energies.

Changes induced by oxygen protonation in the ether link of dimethyl, diethyl and isopropyl methyl ethers and their perfluorinated analogues are studied by comparing the geometrical structure, vibrational characteristics and proton affinities calculated at the RHF level with the 3-21G and 6-31G* bases. This contribution is part of more general research on the effects of surface sites, Lewis acid sites in particular, assumed to play a role in the degradation of lubricants during use.

3-21G RHF calculations on (CF 3 ) 2 O and (CF 3 ) 2 OH + molecules are carried out to assess the changes induced in the molecular properties of ether links in poly(perfluoro ethers) interacting with acid sites at contact surfaces. Geometry of the species, vibrational frequencies, proton affinity, and energetics of the (CF 3 ) 2 OH + fragmentation provide a preliminary basis to understand problems raised by lubricant degradation

Changes induced by oxygen protonation in the ether link of dimethyl, diethyl and isopropyl methyl ethers and their perfluorinated analogues are studied by comparing the geometrical structure, vibrational characteristics and proton affinities calculated at the RHF level with the 3-21G and 6-31G* bases. This contribution is part of more general research on the effects of surface sites, Lewis acid sites in particular, assumed to play a role in the degradation of lubricants during use.

The vitamin K antagonists (VKA) remain to this day the only oral form of therapeutic anticoagulation. Approximately 1% of the French population, mainly elderly, is treated with these anticoagulants. Oral anticoagulants have significant risks of iatrogenic complications; indeed they are the leading cause of such drug-induced complications, predominantly hemorrhages. AFSSAPS (French Drug and Medical Products Agency) clinical practice recommendations, repeatedly disseminated, emphasize the education of patients receiving VKAs. Managing oral anticoagulant treatment is challenging, with a significant risk of under- or overdosing and consequently, thrombosis or hemorrhage. The therapeutic window is narrow, multiple drug-interactions are possible, and the specific dose required for a particular individual to achieve appropriate International Normalized Ratio (INR) levels is unpredictable. The literature contains few randomized controlled trials about the efficacy of education for patients treated with oral anticoagulants. These education programs are not standardized and are therefore varied and difficult to compare. Nevertheless, studies demonstrate the importance of patient education programs in reducing the risk of hemorrhage and achieving better treatment stability. The Grenoble region hospital-community network for vascular diseases (GRANTED) has developed an education program for these patients, consisting of individual sessions for the patient and/or a friend or family member (either at a health care facility or at the patient's home), telephone support and group sessions, and using educational tools and supports. There is also a link with the general practitioner who receives a report. This approach makes it possible to adapt the educational message to individual patients and their daily lives, as well as directly involving them in the management of their treatment.

La chimie industrielle du XXI e siecle se doit de relever de nombreux defis economiques et environnementaux afin d'assurer son developpement futur. Les domaines prioritaires ont trait a l'ingenierie des procedes (thermodynamique, cinetique...) et aux techniques de modelisation (chimie calculatoire, simulations de procedes, dynamique des fluides...). S'il est aujourd'hui communement admis que la chimie quantique constitue une des nombreuses facettes de la chimie physique, le chemin qui mene a la reconnaissance de sa capacite de prediction et d'interpretation de phenomenes physico-chimiques n'a pas pour autant ete un long fleuve tranquille. Loin des diatribes infondees dont elle est encore parfois la cible, la chimie calculatoire est neanmoins occupee a gagner son pari, comme en temoigne cette intervention de Gilbert Gaillard [1], ancien president de la societe francaise Hoechst: « Aujourd'hui, la chimie industrielle a sa source dans la chimie theorique dont elle est l'application, l'accomplissement, et qu'elle contribue a enrichir par les questions qu'elle lui soumet. Par ailleurs, elle met en œuvre les acquis d'autres sciences fondamentales: physique, thermodynamique, mecanique, genie des procedes... Ces apports constituent son paysage quotidien et lui assurent des possibilites de developpement ». Les methodes de chimie quantique impliquent la description mathematique d'un systeme constitue de noyaux et d'electrons, constitutifs de la matiere [2], et la resolution d'equations comme celle de Schrodinger. L'application pratique de ces techniques passe par l'elaboration et la programmation d'algorithmes permettant la description quantitative des phenomenes physiques et chimiques au sein de ce systeme. Les applications de la chimie calculatoire en matiere de genie des procedes sont nombreuses et variees: prediction de donnees spectroscopiques et thermochimiques, developpement de nouvelles molecules possedant une reactivite selective, amelioration des procedes existants et elaboration de nouveaux processus... L'exemple des equations d'etat constitue une excellente illustration de la capacite des ingenieurs chimistes a appliquer et a developper des concepts et des modeles originellement concus par les theoriciens. Cette tendance se precise avec l'avenement et la vulgarisation des equations d'etat non cubiques [3] qui s'imposent avec force au niveau industriel. Les proprietes calculees au niveau quantique peuvent etre utilisees comme variable d'essai pour un traitement posterieur, contribuant ainsi a une certaine continuite entre les differentes etapes de la determination des proprietes physico-chimiques. Ce role d'interface est abondamment utilise au cours de ce travail. Ainsi, la parametrisation d'equations d'etat par la connaissance des parametres critiques des especes chimiques mises en jeu constitue l'essence de cet article. Dans le cadre d'une approche tout a fait generale, les methodes predictives et l'analyse statistique fournissent la clef pour estimer les parametres critiques. Nous avons opte pour la regression lineaire multiple impliquant des variables judicieusement choisies pour leur influence sur ces parametres critiques. Le choix des descripteurs repose sur la determination des proprietes influant sur la valeur de ces parametres critiques et est conditionne par la possibilite d'evaluer ces grandeurs a l'aide des methodes de chimie quantique.

International audience; BACKGROUND: Long-term oral anticoagulation treatment is associated with potential morbidity. Insufficient patient education is linked to poorly controlled anticoagulation. However the impact of a specific educational program on anticoagulation related morbidity remains unknown. OBJECTIVE: To evaluate the effect of an oral anticoagulation patient education program in reducing both hemorrhagic and recurrent thrombotic complications. DESIGN/PARTICIPANTS: We conducted a prospective, multicenter open randomized study, comparing an interventional group who received a specific oral anticoagulation treatment educational program with a control group. Eligible patients were older than 18 and diagnosed as having deep vein thrombosis or pulmonary embolism requiring therapy with a vitamin K antagonist for 3 months or more. Our primary outcome was the occurrence of hemorrhagic or thromboembolic events. RESULTS: During the 3-month follow-up the main outcome criteria were observed 20 times (6.6% of patients), 5 (3.1%) in the experimental and 15 (10.6%) in the control group. Consequently, in multivariate analysis, the cumulative risk reduction in the experimental group was statistically significant (OR 0.25, 95% CI 0.1 - 0.7, p < 0.01). CONCLUSIONS: Patient education using an educational program reduced VKA-related adverse event rates.

This chapter discusses the estimation of critical parameters from quantum mechanics. The QSPR method combined with multiple linear regression is an efficient and elegant way to estimate from scratch the critical parameters of a wide range of compounds. Calculated critical parameters for pure compounds including extrapolation to the limit of extended systems are both in agreement with experimental data and values obtained by group contribution methods, though, in some cases, these contribution methods are unable to correctly describe the saturation behavior of critical temperature. To obtain the critical parameters for binary mixture, the Redlich's logarithmic-hyperbolic interpolation functions have been used. The great advantage of this method is that only critical parameters of pure compounds are required. Two mixtures have been studied butane-hexane, C0 2 -pentane. Calculated mixture critical values are in very good agreement with experimental data, illustrating that the combination of empirical rules and QM is possible and often valuable when carefully performed.