La production scientifique issue de la formation initiale à la faculté de médecine d’Angers entre 2002 et 2008 : de bonne qualité mais insuffisante

IntroductionL’activité de publication scientifique issue de la formation initiale est mal connue. Nous avons évalué la proportion des thèses et des mémoires de spécialité aboutissant à une publication, leur impact en termes de points SIGAPS et les principaux obstacles à la publication de ces travaux. Méthodes Les thèses de doctorat en médecine soutenues de 2002 à 2008 à la faculté de médecine d’Angers ont été recensées à partir du système universitaire de documentation (SUDOC), et les mémoires de spécialité directement auprès des diplômés. Les publications ont été recherchées dans Medline via Pubmed, ISI Web of Knowledge et dans les trois rapports SIGAPS de 2002 à 2008. Une enquête cherchant à connaître les obstacles à la publication a été lancée auprès de tous les directeurs de thèses et responsables de discipline impliqués. Résultats Cinq cent quatre-vingt-dix-huit thèses ont été soutenues, 311 (52 %) en médecine générale et 287 (48 %) en spécialités. Cent soixante-cinq thèses ont donné lieu à publication (28 %) dont 97 (16 %) indexés dans Medline via Pubmed (soit 11 % en médecine générale et 22 % en spécialité). Trente-trois de ces 97 articles (35 %) ont été publiés dans des journaux de haute qualité classés A, B ou C de la classification SIGAPS. Ces articles issus des thèses ont représenté 4,17 % du score SIGAPS du CHU calculé sur un total de 2088 articles au cours de cette période. Deux cent quatre mémoires de spécialités ont donné lieu à 69 articles (33,8 %), dont 50 (24,5 %) indexés dans Medline. Les taux de publication des mémoires de DES et de DESC ont été respectivement de 31 % (45/145) et de 40,7 % (24/59). Ils ont représenté 1,9 % (432 points) du score total SIGAPS. Les principaux obstacles ressentis pour la publication ont été le manque de temps des directeurs, l’éloignement des étudiants après la soutenance et le manque de moyens logistiques. Conclusion La production scientifique issue de la formation initiale à la faculté de médecine d’Angers a été de bonne qualité mais insuffisante quantitativement et peu contributive au financement du CHU malgré un nombre important de diplômés. Un soutien logistique mérite d’être envisagé afin de valoriser la production scientifique issue de la formation initiale

Lattice defects in microtubules: protofilament numbers vary within individual microtubules

We have used cryo-electron microscopy of vitrified specimens to study microtubules assembled both from three cycle purified tubulin (3x-tubulin) and in cell free extracts of Xenopus eggs. In vitro assembled 3x-tubulin samples have a majority of microtubules with 14 protofilaments whereas in cell extracts most microtubules have 13 protofilaments. Microtubule polymorphism was observed in both cases. The number of protofilaments can change abruptly along individual microtubules usually by single increments but double increments also occur. For 3x-tubulin, increasing the magnesium concentration decreases the proportion of 14 protofilament microtubules and decreases the average separation between transitions in these microtubules. Protofilament discontinuities may correspond to dislocation-like defects in the microtubule surface lattice

Pooled analysis of higher versus lower blood pressure targets for vasopressor therapy septic and vasodilatory shock

PURPOSE: Guidelines for shock recommend mean arterial pressure (MAP) targets for vasopressor therapy of at least 65 mmHg and, until recently, suggested that patients with underlying chronic hypertension and atherosclerosis may benefit from higher targets. We conducted an individual patient-data meta-analysis of recent trials to determine if patient variables modify the effect of different MAP targets. METHODS: We searched the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials for randomized controlled trials of higher versus lower blood pressure targets for vasopressor therapy in adult patients in shock (until November 2017). After obtaining individual patient data from both eligible trials, we used a modified version of the Cochrane Collaboration\u27s instrument to assess the risk of bias of included trials. The primary outcome was 28-day mortality. RESULTS: Included trials enrolled 894 patients. Controlling for trial and site, the OR for 28-day mortality for the higher versus lower MAP targets was 1.15 (95% CI 0.87-1.52). Treatment effect varied by duration of vasopressors before randomization (interaction p = 0.017), but not by chronic hypertension, congestive heart failure or age. Risk of death increased in higher MAP groups among patients on vasopressors > 6 h before randomization (OR 3.00, 95% CI 1.33-6.74). CONCLUSIONS: Targeting higher blood pressure targets may increase mortality in patients who have been treated with vasopressors for more than 6 h. Lower blood pressure targets were not associated with patient-important adverse events in any subgroup, including chronically hypertensive patients

Continuous non-perturbative regularization of QED

We regularize in a continuous manner the path integral of QED by construction of a non-local version of its action by means of a regularized form of Dirac's $\delta$ functions. Since the action and the measure are both invariant under the gauge group, this regularization scheme is intrinsically non-perturbative. Despite the fact that the non-local action converges formally to the local one as the cutoff goes to infinity, the regularized theory keeps trace of the non-locality through the appearance of a quadratic divergence in the transverse part of the polarization operator. This term which is uniquely defined by the choice of the cutoff functions can be removed by a redefinition of the regularized action. We notice that as for chiral fermions on the lattice, there is an obstruction to construct a continuous and non ambiguous regularization in four dimensions. With the help of the regularized equations of motion, we calculate the one particle irreducible functions which are known to be divergent by naive power counting at the one loop order.Comment: 23 pages, LaTeX, 5 Encapsulated Postscript figures. Improved and revised version, to appear in Phys. Rev.

Trends in Metal Oxide Stability for Nanorods, Nanotubes, and Surfaces

The formation energies of nanostructures play an important role in determining their properties, including the catalytic activity. For the case of 15 different rutile and 8 different perovskite metal oxides, we find that the density functional theory (DFT) calculated formation energies of (2,2) nanorods, (3,3) nanotubes, and the (110) and (100) surfaces may be described semi-quantitatively by the fraction of metal--oxygen bonds broken and the bonding band centers in the bulk metal oxide

Global QSAR models of skin sensitisers for regulatory purposes

Abstract Background The new European Regulation on chemical safety, REACH, (Registration, Evaluation, Authorisation and Restriction of CHemical substances), is in the process of being implemented. Many chemicals used in industry require additional testing to comply with the REACH regulations. At the same time EU member states are attempting to reduce the number of animals used in experiments under the 3 Rs policy, (refining, reducing, and replacing the use of animals in laboratory procedures). Computational techniques such as QSAR have the potential to offer an alternative for generating REACH data. The FP6 project CAESAR was aimed at developing QSAR models for 5 key toxicological endpoints of which skin sensitisation was one. Results This paper reports the development of two global QSAR models using two different computational approaches, which contribute to the hybrid model freely available online. Conclusions The QSAR models for assessing skin sensitisation have been developed and tested under stringent quality criteria to fulfil the principles laid down by the OECD. The final models, accessible from CAESAR website, offer a robust and reliable method of assessing skin sensitisation for regulatory use.</p

Tau Interaction with Tubulin and Microtubules: From Purified Proteins to Cells

International audienceMicrotubules (MTs) play an important role in many cellular processes and are dynamic structures regulated by an important network of microtubules-associated proteins, MAPs, such as Tau. Tau has been discovered as an essential factor for MTs formation in vitro, and its region implicated in binding to MTs has been identified. By contrast, the affinity, the stoichiometry, and the topology of Tau-MTs interaction remain controversial. Indeed, depending on the experiment conditions a wide range of values have been obtained. In this chapter, we focus on three biophysical methods, turbidimetry, cosedimentation assay, and Förster Resonance Energy Transfer to study Tau-tubulin interaction both in vitro and in cell. We highlight precautions that must be taken in order to avoid pitfalls and we detail the nature of the conclusions that can be drawn from these methods about Tau-tubulin interaction

The exceptionally powerful TeV gamma-ray emitters in the Large Magellanic Cloud

The Large Magellanic Cloud, a satellite galaxy of the Milky Way, has been observed with the High Energy Stereoscopic System (H.E.S.S.) above an energy of 100 billion electron volts for a deep exposure of 210 hours. Three sources of different types were detected: the pulsar wind nebula of the most energetic pulsar known N 157B, the radio-loud supernova remnant N 132D and the largest non-thermal X-ray shell - the superbubble 30 Dor C. The unique object SN 1987A is, surprisingly, not detected, which constrains the theoretical framework of particle acceleration in very young supernova remnants. These detections reveal the most energetic tip of a gamma-ray source population in an external galaxy, and provide via 30 Dor C the unambiguous detection of gamma-ray emission from a superbubble.Comment: Published in Science Magazine (Jan. 23, 2015). This ArXiv version has the supplementary online material incorporated as an appendix to the main pape