269 resultados para Approche design
Resumo:
Essential hypertension is a multifactorial disorder and is the main risk factor for renal and cardiovascular complications. The research on the genetics of hypertension has been frustrated by the small predictive value of the discovered genetic variants. The HYPERGENES Project investigated associations between genetic variants and essential hypertension pursuing a 2-stage study by recruiting cases and controls from extensively characterized cohorts recruited over many years in different European regions. The discovery phase consisted of 1865 cases and 1750 controls genotyped with 1M Illumina array. Best hits were followed up in a validation panel of 1385 cases and 1246 controls that were genotyped with a custom array of 14 055 markers. We identified a new hypertension susceptibility locus (rs3918226) in the promoter region of the endothelial NO synthase gene (odds ratio: 1.54 [95% CI: 1.37-1.73]; combined P=2.58 · 10(-13)). A meta-analysis, using other in silico/de novo genotyping data for a total of 21 714 subjects, resulted in an overall odds ratio of 1.34 (95% CI: 1.25-1.44; P=1.032 · 10(-14)). The quantitative analysis on a population-based sample revealed an effect size of 1.91 (95% CI: 0.16-3.66) for systolic and 1.40 (95% CI: 0.25-2.55) for diastolic blood pressure. We identified in silico a potential binding site for ETS transcription factors directly next to rs3918226, suggesting a potential modulation of endothelial NO synthase expression. Biological evidence links endothelial NO synthase with hypertension, because it is a critical mediator of cardiovascular homeostasis and blood pressure control via vascular tone regulation. This finding supports the hypothesis that there may be a causal genetic variation at this locus.
Resumo:
Résumé : La société sénégalaise traverse une crise profonde qui touche tous les secteurs de la vie. Cette crise à la fois structurelle et conjoncturelle crée à son tour une sorte de société de la crise qui touche les populations les plus vulnérables. Le phénomène des enfants de la rue est l'expression parfaite de cette société de la crise. Le rythme dans lequel il se développe est la traduction de la dynamique d'exclusion qui sévit en milieu urbain sénégalais en général et dans la région de Dakar en particulier. Dans cette région, l'urbanisation s'est accompagnée de la montée des inégalités qui placent la société dans une sorte de dualisation entre centre et périphérie. A la ville de Dakar qui s'est constituée selon les normes de la planification urbaine, s'oppose les principales banlieues de Pikine, Guédiawaye et Rufisque qui offrent le visage de marges sociales urbaines. D'une certaine manière, la montée des inégalités remet en cause les politiques sociales, de la bonne gouvernance et de la redistribution des richesses. Ces banlieues constituent les principaux milieux d'accueil de la masse de migrants ruraux qui fuient la misère des villages. D'une part, l'hétérogénéité sociale de ces banlieues ne favorise pas l'émergence d'une conscience collective fondée sur l'appartenance à un fonds historique commun. Par contre, elle renforce l'anonymat et l'indifférence propres à la ville. D'autre part, les difficultés économiques et la précarité des conditions de vie conjuguées à l'explosion démographique et ses conséquences affaiblissent les systèmes de solidarité entraînant ainsi la montée de l'individualisme et la philosophie du chacun pour soi. Ce qui met en cause l'éducation des enfants qui devient difficile pour les parents d'assumer. En outre, la place importante accordée à l'imaginaire social dans la société sénégalaise explique le recours aux forces surnaturelles par l'intercession des marabouts, sorciers, devins, etc. D'autre part, la place accordée aux offrandes et aux sacrifices de même que le "besoin de donner" alimente et pérennise la pratique de la mendicité en général et celle des enfants en particulier. En outre, l'instrumentalisation de la mendicité par certains marabouts qui se traduit par une sorte de "business talibé" ou de "marché de l'aumône", rapproche les enfants de l'univers de là rue qui devient pour eux une sorte d'échappatoire face aux conditions de vie que leur imposent ces marabouts. Ainsi, pour eux, la rue remplit une fonction de socialisation. En effet, dans cet univers social, les enfants se forgent une personnalité, développent des compétences et des activités qui leur permettent de survivre, créent des repères et des codes collectifs qui leur permettent de mener une existence que la société assimile strictement à la déviance. Mots clé : crise, école, éducation, enfants de la rue, exclusion, inégalités, migration, pauvreté, socialisation, stratégies de survie, uibanisation.
Resumo:
The n-octanol/water partition coefficient (log Po/w) is a key physicochemical parameter for drug discovery, design, and development. Here, we present a physics-based approach that shows a strong linear correlation between the computed solvation free energy in implicit solvents and the experimental log Po/w on a cleansed data set of more than 17,500 molecules. After internal validation by five-fold cross-validation and data randomization, the predictive power of the most interesting multiple linear model, based on two GB/SA parameters solely, was tested on two different external sets of molecules. On the Martel druglike test set, the predictive power of the best model (N = 706, r = 0.64, MAE = 1.18, and RMSE = 1.40) is similar to six well-established empirical methods. On the 17-drug test set, our model outperformed all compared empirical methodologies (N = 17, r = 0.94, MAE = 0.38, and RMSE = 0.52). The physical basis of our original GB/SA approach together with its predictive capacity, computational efficiency (1 to 2 s per molecule), and tridimensional molecular graphics capability lay the foundations for a promising predictor, the implicit log P method (iLOGP), to complement the portfolio of drug design tools developed and provided by the SIB Swiss Institute of Bioinformatics.
Resumo:
Hypoglycaemia can occur if the endogenous liver glucose output is lower than the glucose uptake in insulin-sensitive and insulin-insensitive tissues. The onset of hypoglycaemia induces the production of counterregulatory hormones such as glucagon, epinephrine, growth hormone and cortisol, and symptoms of neuroglycopenia. The correlation between biological hypoglycaemia and the symptoms associated with low blood sugar is particularly poor in diabetic patients and in patients with suspected postprandial hypoglycaemia. It is important to discriminate between fasting and postprandial hypoglycaemia. Idiopathic postprandial hypoglycaemia should be diagnosed clinically without further laboratory assessment, whereas the etiology of a fasting hypoglycaemia needs to be clarified further by laboratory testing, as it is potentially life-threatening.
Resumo:
The HbpR protein is the sigma54-dependent transcription activator for 2-hydroxybiphenyl degradation in Pseudomonas azelaica. The ability of HbpR and XylR, which share 35% amino acid sequence identity, to cross-activate the PhbpC and Pu promoters was investigated by determining HbpR- or XylR-mediated luciferase expression and by DNA binding assays. XylR measurably activated the PhbpC promoter in the presence of the effector m-xylene, both in Escherichia coli and Pseudomonas putida. HbpR weakly stimulated the Pu promoter in E. coli but not in P. azelaica. Poor HbpR-dependent activation from Pu was caused by a weak binding to the operator region. To create promoters efficiently activated by both regulators, the HbpR binding sites on PhbpC were gradually changed into the XylR binding sites of Pu by site-directed mutagenesis. Inducible luciferase expression from mutated promoters was tested in E. coli on a two plasmid system, and from mono copy gene fusions in P. azelaica and P. putida. Some mutants were efficiently activated by both HbpR and XylR, showing that promoters can be created which are permissive for both regulators. Others achieved a higher XylR-dependent transcription than from Pu itself. Mutants were also obtained which displayed a tenfold lower uninduced expression level by HbpR than the wild-type PhbpC, while keeping the same maximal induction level. On the basis of these results, a dual-responsive bioreporter strain of P. azelaica was created, containing both XylR and HbpR, and activating luciferase expression from the same single promoter independently with m-xylene and 2-hydroxybiphenyl.
Resumo:
Ce rapport présente plusieurs axes relatifs aux jeux de hasard et d'argent et au jeu problématique. Comment comprendre l'évolution de ce type de problématique dans une société? C'est au travers d'une analyse sur les représentations sociales en Suisse romande que ce travail propose une piste de réflexion et ceci dans le but de dresser un état des lieux de ces thématiques telles qu'elles existent dans les consciences collectives. Les représentations sociales ont fait l'objet de nombreuses études en Amérique du Nord mais sont par contre plutôt rares en Suisse. Nous avons pu constater au fil de ce travail que les représentations sont teintées de prudence; la population générale sollicitée ne semble pas ignorer quels sont les écueils pouvant être générés par ces pratiques; mais, en revanche, d'autres résultats nous ont permis de comprendre que le jeu problématique n'est pas encore intégré par l'ensemble de la population puisque 42.6% n'en ont jamais entendu parler. Il y a donc une brèche à exploiter en la matière tant d'un point de vue préventif que scientifique. Afin d'apporter une réalité supplémentaire et concrète à ces considérations d'ordre subjectif, nous avons agrémenté ce rapport d'analyses propres à l'épidémiologie du jeu en Suisse, et ceci au travers des données relatives aux Enquêtes suisses sur la santé 2002 et 2007. Finalement, un certain nombre d'outils de mesure et de dépistage à l'égard du jeu pathologique ont été sélectionnés dans la littérature internationale, et ceci dans le but de mieux comprendre quels sont les critères privilégiés permettant de déterminer ou diagnostiquer un joueur à risque. Le présent rapport offre donc un éventail de ce que sont les jeux et de ce qu'ils représentent dans notre société et délivre des informations diverses sur leurs appréhensions tant au niveau individuel que médical et social.
Resumo:
This article intends to grasp the stabilization process, deterioration or improvement of the conjugal intimacy over five years, based on a representative sample of couples living in Switzerland. The dynamics develop in different ways depending on the degree of autonomy of the partners, the gendering of household tasks, conjugal openess and the coping strategies of the couples.
Resumo:
Purpose Carbon-13 magnetic resonance spectroscopy (13C-MRS) is challenging because of the inherent low sensitivity of 13C detection and the need for radiofrequency transmission at the 1H frequency while receiving the 13C signal, the latter requiring electrical decoupling of the 13C and 1H radiofrequency channels. In this study, we added traps to the 13C coil to construct a quadrature-13C/quadrature-1H surface coil, with sufficient isolation between channels to allow simultaneous operation at both frequencies without compromise in coil performance. Methods Isolation between channels was evaluated on the bench by measuring all coupling parameters. The quadrature mode of the quadrature-13C coil was assessed using in vitro 23Na gradient echo images. The signal-to-noise ratio (SNR) was measured on the glycogen and glucose resonances by 13C-MRS in vitro, compared with that obtained with a linear-13C/quadrature-1H coil, and validated by 13C-MRS in vivo in the human calf at 7T. Results Isolation between channels was better than â^'30 dB. The 23Na gradient echo images indicate a region where the field is strongly circularly polarized. The quadrature coil provided an SNR enhancement over a linear coil of 1.4, in vitro and in vivo. Conclusion It is feasible to construct a double-quadrature 13C-1H surface coil for proton decoupled sensitivity enhanced 13C-NMR spectroscopy in humans at 7T. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc.
Resumo:
Under the referential of a ternary logic, this article aims to focus on the geographical map perceived as a visual object and the question of surfaces of representation. We analyse the status of map making versus landscape representation, the relations between a map and a painted picture. A ternary model of the pictural composition perspective|light/pictural field is proposed. The frame of the map, articulating the space that is cut out and the space included is discussed in a parallel between maps and painted pictures.
Resumo:
PURPOSE: Multinuclear magnetic resonance spectroscopy and imaging require a radiofrequency probe capable of transmitting and receiving at the proton and non-proton frequencies. To minimize coupling between probe elements tuned to different frequencies, LC (inductor-capacitor) traps blocking current at the (1) H frequency can be inserted in non-proton elements. This work compares LC traps with LCC traps, a modified design incorporating an additional capacitor, enabling control of the trap reactance at the low frequency while maintaining (1) H blocking. METHODS: Losses introduced by both types of trap were analysed using circuit models. Radiofrequency coils incorporating a series of LC and LCC traps were then built and evaluated at the bench. LCC trap performance was then confirmed using (1) H and (13) C measurements in a 7T human scanner. RESULTS: LC and LCC traps both effectively block interaction between non-proton and proton coils at the proton frequency. LCC traps were found to introduce a sensitivity reduction of 5±2%, which was less than half of that caused by LC traps. CONCLUSION: Sensitivity of non-proton coils is critical. The improved trap design, incorporating one extra capacitor, significantly reduces losses introduced by the trap in the non-proton coil. Magn Reson Med 72:584-590, 2014. © 2013 Wiley Periodicals, Inc.