957 resultados para self-awareness


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PURPOSE: Glioblastomas are notorious for resistance to therapy, which has been attributed to DNA-repair proficiency, a multitude of deregulated molecular pathways, and, more recently, to the particular biologic behavior of tumor stem-like cells. Here, we aimed to identify molecular profiles specific for treatment resistance to the current standard of care of concomitant chemoradiotherapy with the alkylating agent temozolomide. PATIENTS AND METHODS: Gene expression profiles of 80 glioblastomas were interrogated for associations with resistance to therapy. Patients were treated within clinical trials testing the addition of concomitant and adjuvant temozolomide to radiotherapy. RESULTS: An expression signature dominated by HOX genes, which comprises Prominin-1 (CD133), emerged as a predictor for poor survival in patients treated with concomitant chemoradiotherapy (n = 42; hazard ratio = 2.69; 95% CI, 1.38 to 5.26; P = .004). This association could be validated in an independent data set. Provocatively, the HOX cluster was reminiscent of a "self-renewal" signature (P = .008; Gene Set Enrichment Analysis) recently characterized in a mouse leukemia model. The HOX signature and EGFR expression were independent prognostic factors in multivariate analysis, adjusted for the O-6-methylguanine-DNA methyltransferase (MGMT) methylation status, a known predictive factor for benefit from temozolomide, and age. Better outcome was associated with gene clusters characterizing features of tumor-host interaction including tumor vascularization and cell adhesion, and innate immune response. CONCLUSION: This study provides first clinical evidence for the implication of a "glioma stem cell" or "self-renewal" phenotype in treatment resistance of glioblastoma. Biologic mechanisms identified here to be relevant for resistance will guide future targeted therapies and respective marker development for individualized treatment and patient selection.

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Propagation of localized orientational waves, as imaged by Brewster angle microscopy, is induced by low intensity linearly polarized light inside axisymmetric smectic-C confined domains in a photosensitive molecular thin film at the air/water interface (Langmuir monolayer). Results from numerical simulations of a model that couples photoreorientational effects and long-range elastic forces are presented. Differences are stressed between our scenario and the paradigmatic wave phenomena in excitable chemical media.

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Propagation of localized orientational waves, as imaged by Brewster angle microscopy, is induced by low intensity linearly polarized light inside axisymmetric smectic-C confined domains in a photosensitive molecular thin film at the air/water interface (Langmuir monolayer). Results from numerical simulations of a model that couples photoreorientational effects and long-range elastic forces are presented. Differences are stressed between our scenario and the paradigmatic wave phenomena in excitable chemical media.

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Both public and private insurance for long-term care is undeveloped in some European countries such as in Spain and empirical evidence is still limited. This paper aims at exmining the determinants of the demand for Long Term Care (LTC) coverage in Spain using contingent valuation techniques. Our findings indicate that only one-fifth of the population is willing to pay to assure coverage decisions are significantly affected by private information asymmetry and housing tenure in giving rise to self-insurance reduces the probability of insurance being hypothetically purchased.

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OBJECTIVE: Because of its high prevalence, early screening for occupational asthma (OA) is crucial. We aimed to evaluate the screening performance of the Occupational Asthma Screening Questionnaire-11 items (OASQ-11) in a clinical setting. METHODS: Between January 2009 and December 2011, 169 workers referred for potential OA to our hospital completed the OASQ-11 and underwent workups to determine the final diagnosis. The discriminative abilities of the OASQ-11 as a whole and in relation to demographic and exposure parameters were determined by the area under the receiving operator characteristic curve (AUC). RESULTS: Model 1, consisting of the OASQ's items, showed fair discrimination (AUC, 0.69; 95% confidence interval, 0.58 to 0.80). Addition of age and exposure duration to model 1 improved discrimination (AUC, 0.80; confidence interval, 0.72 to 0.88). CONCLUSION: A simple model consisting of the OASQ-11's items, age, and exposure duration could well discriminate subjects with OA in a clinical setting.

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Division of labor is a complex phenomenon observed throughout nature. Theoretical studies have focused either on its emergence through self-organization mechanisms or on its adaptive consequences. We suggest that the interaction of self-organization, which undoubtedly characterizes division of labor in social insects, and evolution should be further explored. We review the factors empirically shown to influence task choice. In light of these factors, we review the most important self-organization and evolutionary models for division of labor and outline their advantages and limitations. We describe ways to unify evolution and self-organization in the theoretical study of division of labor and recent results in this area. Finally, we discuss some benchmarks and primary challenges of this approach.

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The Iowa State Capitol: A Self-Guided Tour

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BACKGROUND: In an experimental setting, the performance of the LifeBox, a new portable extracorporeal membrane oxygenator (ECMO) system suitable for patient transport, is presented. Standard rectilinear percutaneous cannulae are normally employed for this purpose, but have limited flow and pressure delivery due to their rigid structure. Therefore, we aimed to determine the potential for flow increase by using self-expanding venous cannulae. METHODS: Veno-arterial bypass was established in three pigs (40.6+/-5.1 kg). The venous line of the cardiopulmonary bypass was established by cannulation of the external jugular vein. The arterial side of the circulation was secured by cannulation of the common carotid artery. Two different venous cannulae (SmartCanula 18/36F 430mm and Biomedicus 19F) were examined for their functional integrity when used in conjunction with the centrifugal pump (500-3000 RPM) of the LifeBox system. RESULTS: At 1500, 2000, 2500, and 3000 RPM, the blood flow increased steadily for each cannula, but remained higher in the self-expanding cannula. That is, the 19F rectilinear cannula achieved a blood flow of 0.93+/-0.14, 1.47+/-0.37, 1.9+/-0.68, and 1.5+/-0.9 l/min, respectively, and the 18/36F self-expanding cannula achieved 1.1+/-0.1, 1.9+/-0.33, 2.8+/-0.39 and 3.66+/-0.52 l/min. However, when tested for venous line pressure, the standard venous cannula achieved -29+/-10.7mmHg while the self-expanding cannula achieved -13.6 +/-4.3mmHg at 1500 RMP. As the RPM increased from 2500 to 3000, the venous line pressure accounted for -141.9+/-20 and -98+/-7.3mmHg for the 19F rectilinear cannula and -30.6+/-6.4 and -45+/-11.6mmHg for the self-expanding cannula. CONCLUSION: The self-expanding cannula exhibited superior venous drainage ability when compared to the performance of the standard rectilinear cannula with the use of the LifeBox. The flow rate achieved was approximately 40% greater than the standard drainage device, with a maximal pump flow recorded at 4.3l/min.

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Division of labor in social insects is determinant to their ecological success. Recent models emphasize that division of labor is an emergent property of the interactions among nestmates obeying to simple behavioral rules. However, the role of evolution in shaping these rules has been largely neglected. Here, we investigate a model that integrates the perspectives of self-organization and evolution. Our point of departure is the response threshold model, where we allow thresholds to evolve. We ask whether the thresholds will evolve to a state where division of labor emerges in a form that fits the needs of the colony. We find that division of labor can indeed evolve through the evolutionary branching of thresholds, leading to workers that differ in their tendency to take on a given task. However, the conditions under which division of labor evolves depend on the strength of selection on the two fitness components considered: amount of work performed and on worker distribution over tasks. When selection is strongest on the amount of work performed, division of labor evolves if switching tasks is costly. When selection is strongest on worker distribution, division of labor is less likely to evolve. Furthermore, we show that a biased distribution (like 3:1) of workers over tasks is not easily achievable by a threshold mechanism, even under strong selection. Contrary to expectation, multiple matings of colony foundresses impede the evolution of specialization. Overall, our model sheds light on the importance of considering the interaction between specific mechanisms and ecological requirements to better understand the evolutionary scenarios that lead to division of labor in complex systems. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00265-012-1343-2) contains supplementary material, which is available to authorized users.

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Le diabète de type 2 (DT2) a une prévalence élevée dans les pays industrialisés, et on s'attend à une augmentation dans les années à venir en raison du vieillissement de la population ainsi que des modifications du mode de vie. Il existe malheureusement peu de données épidémiologiques sur la prévalence et la prise en charge du diabète en Suisse. Les objectifs de cette étude étaient donc 1) évaluer la prévalence du DT2 dans une cohorte lausannoise ; 2) caractériser la prise en charge des patients atteints de DT2, et 3) identifier les facteurs associés à la prévalence, la connaissance par les patients de leur maladie et le traitement du DT2. Pour ce faire, 6181 sujets (3246 femmes), âgés de 35 à 75 ans et vivant à Lausanne ont été inclus dans l'étude. La prévalence totale du DT2 était de 6.3% (intervalle de confiance à 95%: 5.7-7.0%), une valeur comparable à celle des pays avoisinants. La prévalence était plus élevée chez les hommes que chez les femmes (9.1% contre 3.8%, p<0.001), et augmentait avec l'âge. Deux tiers des patients avec DT2 (65.3% ; 60.4-70.0%) avaient connaissance de leur situation, et plus de trois-quarts d'entre eux étaient traités. Les hommes étaient plus fréquemment traités que les femmes (91.3% contre 75.9%, p<0.001). La plupart des patients suivait une monothérapie (majoritairement par biguanides). Parmi les sujets avec une thérapie multiple, une prévalence plus élevée de glycémie à jeun >7 mmol/1 était présente. L'analyse multivariée a montré que le sexe masculin, l'âge croissant et un indice de masse corporelle élevé étaient associés à une plus grande prévalence du DT2, alors qu'aucune association n'a été trouvée pour l'activité physique et la consommation d'alcool. Parmi les sujets atteints de DT2, l'âge croissant était positivement associé à la connaissance du diabète, de même que l'âge croissant et le sexe masculin étaient associés à une plus grande prévalence du traitement. Le faible taux de connaissance de diabète pourrait être dû à un manque de dépistage par les médecins de premier recours. La présence d'autres facteurs de risque cardiovasculaire devrait inciter les médecins à un dépistage du diabète pour obtenir un meilleur profil de risque. Cette étude a des limitations. D'abord, aucune mesure de l'hémoglobine glyquée n'a été mesurée, et par conséquent la détermination de la prise en charge uniquement par la glycémie à jeun peut être difficile. Ensuite, le taux de participation était bas et pourrait limiter l'interprétation des résultats ; néanmoins, il est comparable à celui d'autres études effectuées dans les pays occidentaux. Il existe peu de données épidémiologiques du DT2 en Suisse, cette étude permet donc d'évaluer la situation actuelle et de déterminer la prévalence et la prise en charge du diabète à Lausanne à travers la cohorte CoLaus. Une telle étude a par conséquent son importance dans le contexte actuel, au vu du vieillissement de la population et de l'augmentation des facteurs de risque cardio-vasculaires.

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Self-measurement of blood pressure (SMBP) is increasingly used to assess blood pressure outside the medical setting. A prerequisite for the wide use of SMBP is the availability of validated devices providing reliable readings when they are handled by patients. This is the case today with a number of fully automated oscillometric apparatuses. A major advantage of SMBP is the great number of readings, which is linked with high reproducibility. Given these advantages, one of the major indications for SMBP is the need for evaluation of antihypertensive treatment, either for individual patients in everyday practice or in clinical trials intended to characterize the effects of blood-pressure-lowering medications. In fact, SMBP is particularly helpful for evaluating resistant hypertension and detecting white-coat effect in patients exhibiting high office blood pressure under antihypertensive therapy. SMBP might also motivate the patient and improve his or her adherence to long-term treatment. Moreover, SMBP can be used as a sensitive technique for evaluating the effect of antihypertensive drugs in clinical trials; it increases the power of comparative trials, allowing one to study fewer patients or to detect smaller differences in blood pressure than would be possible with the office measurement. Therefore, SMBP can be regarded as a valuable technique for the follow-up of treated patients as well as for the assessment of antihypertensive drugs in clinical trials.

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Background: Well-conducted behavioural surveillance (BS) is essential for policy planning and evaluation. Data should be comparable across countries. In 2008, the European Centre for Disease Prevention and Control (ECDC) began a programme to support Member States in the implementation of BS for Second Generation Surveillance. Methods: Data from a mapping exercise on current BS activities in EU/EFTA countries led to recommendations for establishing national BS systems and international coordination, and the definition of a set of core and transversal (UNGASS-Dublin compatible) indicators for BS in the general and eight specific populations. A toolkit for establishing BS has been developed and a BS needs-assessment survey has been launched in 30 countries. Tools for BS self-assessment and planning are currently being tested during interactive workshops with country representatives. Results: The mapping exercise revealed extreme diversity between countries. Around half had established a BS system, but this did not always correspond to the epidemiological situation. Challenges to implementation and harmonisation at all levels emerged from survey findings and workshop feedback. These include: absence of synergy between biological and behavioural surveillance and of actors having an overall view of all system elements; lack of awareness of the relevance of BS and of coordination between agencies; insufficient use of available data; financial constraints; poor sustainability, data quality and access to certain key populations; unfavourable legislative environments. Conclusions: There is widespread need in the region not only for technical support but also for BS advocacy: BS remains the neglected partner of second generation surveillance and requires increased political support and capacity-building in order to become effective. Dissemination of validated tools for BS, developed in interaction with country experts, proves feasible and acceptable.