283 resultados para Self-dual matroids


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The aim of this report is to address the benefits of the minimal invasive venous drainage in a pediatric cardio surgical scenario. Juvenile bovine experiments (67.4+/-11 kg) were performed. The right atrium was cannulated in a trans-jugular way by using the self-expandable (Smart Stat, 12/20F, 430 mm) venous cannula (Smartcannula LLC, Lausanne, Switzerland) vs. a 14F 250 mm (Polystan Lighthouse) standard pediatric venous cannula. Establishing the cardiopulmonary bypass (CPB), the blood flows were assessed for 20 mmHg, 30 mmHg and 40 mmHg of driving pressure. Venous drainage (flow in l/min) at 20 mmHg, 30 mmHg, and 40 mmHg drainage load was 0.26+/-0.1, 0.35+/-0.2 and 0.28+/-0.08 for the 14F standard vs. 1.31+/-0.22, 1.35+/-0.24 and 1.9+/-0.2 for the Smart Stat 12/20F cannula. The 43 cm self-expanding 12/20F Smartcannula outperforms the 14F standard cannula. The results described herein allow us to conclude that usage of the self-expanding Smartcannula also in the pediatric patients improves the flow and the drainage capacity, avoiding the insufficient and excessive drainage. We believe that similar results may be expected in the clinical settings.

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Host-cell factor 1 (HCF-1) is an unusual transcriptional regulator that undergoes a process of proteolytic maturation to generate N- (HCF-1(N)) and C- (HCF-1(C)) terminal subunits noncovalently associated via self-association sequence elements. Here, we present the crystal structure of the self-association sequence 1 (SAS1) including the adjacent C-terminal HCF-1 nuclear localization signal (NLS). SAS1 elements from each of the HCF-1(N) and HCF-1(C) subunits form an interdigitated fibronectin type 3 (Fn3) tandem repeat structure. We show that the C-terminal NLS recruited by the interdigitated SAS1 structure is required for effective formation of a transcriptional regulatory complex: the herpes simplex virus VP16-induced complex. Thus, HCF-1(N)-HCF-1(C) association via an integrated Fn3 structure permits an NLS to facilitate formation of a transcriptional regulatory complex.

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Rapport de SynthèseLa thérapie antirétrovirale a progressée de manière significative depuis te début de l'épidémie du syndrome d'immunodéficience acquise (SIDA). Durant les 20 dernières années, plusieurs combinaisons de traitements ont été utilisées avec succès menant à une réduction de la mortalité associée. Par contre, le traitement a aussi engendré des cas de résistances multiples avec comme résultat, le besoin d'utiliser plusieurs molécules en combinaison, et une augmentation des cas de toxicité. Une stratégie souvent employée fût la combinaison de deux molécules inhibitrices de la protéase en même temps en combinaison avec une troisième molécule, le ritonavir. (DBPI).La cohorte Suisse sur le VIH existe depuis 1987 et permet d'étudier de façon longitudinale les patients qui y sont inscrits. Pour ce travail de thèse, nous avons étudié les patients inscrits à la cohorte suisse de 1996 à 2007 qui ont reçu une combinaison DBPI.Pendant la période étudiée, un total de 405 patients ont reçu un traitement DBPI, dont 295 patients ont reçu le DBPI pour plus de 6 mois. La durée médiane du traitement était de 2.2 ans. Sur les 287 patients qui étaient en échec viral au début du traitement (défini comme HIV RNA>400 copies/ml), 64.1% ont réussi à supprimer la virémie et 54.4% ont eu une suppression dans les 24 semaines qui ont suivi le début de la thérapie. Les patients avaient reçu en moyenne 6 combinaisons de traitement différentes avant le début de la thérapie DBPi. Pour les patients qui ont arrêté le traitement DBPI, la cause principale de l'arrêt était due au souhait du patient (48.3%), à l'échec virologique (22.5%) et à la toxicité (15.8%). Les patients ayant reçu le traitement après 1999, ou ayant été traités avec une combinaison de Lopinavir-ritonvir/saquinavir ou lopinavir-ritonavir/atazanavir arrivaient à supprimer leur virémie plus souvent que ceux qui avaient reçu d'autres combinaisons.Cette étude constitue la plus grande étude publiée sur le sujet de l'utilisation des DBPI pour les patients à résistances multiples. Malgré le fait que c'est une étude observationnelle, nous pouvons attester que le taux de succès était de 64.4%, le taux de toxicité était relativement bas (15.8%) et que la plus part des patients ont toléré ces combinaisons, malgré le taux élevé d'effets secondaires souvent rapportés. En somme, cette approche pourrait être envisagée dans des situations ou les nouveaux traitements tels que les inhibiteurs de l'intégrase et du CCR5 ne sont pas encore disponibles.

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Abstract The neo-liberal capitalist ideology has come under heavy fire with anecdotal evidence indicating a link between these same values and unethical behavior. Academic institutions reflect social values and act as socializing agents for the young. Can this explain the high and increasing rates of cheating that currently prevail in education? Our first chapter examines the question of whether self-enhancement values of power and açhievement, the individual level equivalent of neo-liberal capitalist values, predict positive attitudes towards cheating. Furthermore, we explore the mediating role of motivational factors. Results of four studies reveal that self-enhancement value endorsement predicts the adoption of performance-approach goals, a relationship mediated by introjected regulation, namely desire for social approval and that self-enhancement value endorsement also predicts the condoning of cheating, a relationship mediated by performance-approach goal adoption. However, self-transcendence values prescribed by a normatively salient source have the potential to reduce the link between self-enhancement value endorsément and attitudes towards cheating. Normative assessment constitutes a key tool used by academic institutions to socialize young people to accept the competitive, meritocratic nature of a sociéty driven by a neo-liberal capitalist ideology. As such, the manifest function of grades is to motivate students to work hard and to buy into the competing ethos. Does normative assessment fulfill these functions? Our second chapter explores the reward-intrinsic motivation question in the context of grading, arguably a high-stakes reward. In two experiments, the relative capacity of graded high performance as compared to the task autonomy experienced in an ungraded task to predict post-task intrinsic motivation is assessed. Results show that whilst the graded task performance predicts post-task appreciation, it fails to predict ongoing motivation. However, perceived autonomy experienced in non-graded condition, predicts both post-task appreciation and ongoing motivation. Our third chapter asks whether normative assessment inspires the spirit of competition in students. Results of three experimental studies reveal that expectation of a grade for a task, compared to no grade, induces greater adoption of performance-avoidance, but not performance-approach, goals. Experiment 3 provides an explanatory mechanism for this, showing that reduced autonomous motivation experienced in previous graded tasks mediates the relationship between grading and adoption of performance avoidance goals in a subsequent task. The above results, when combined, provide evidence as to the deleterious effects of self enhancement values and the associated practice of normative assessment in school on student motivation, goals and ethics. We conclude by using value and motivation theory to explore solutions to this problem.

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BACKGROUND: Good adherence to antiretroviral therapy (ART) is critical for successful HIV treatment. However, some patients remain virologically suppressed despite suboptimal adherence. We hypothesized that this could result from host genetic factors influencing drug levels. METHODS: Eligible individuals were Caucasians treated with efavirenz (EFV) and/or boosted lopinavir (LPV/r) with self-reported poor adherence, defined as missing doses of ART at least weekly for more than 6 months. Participants were genotyped for single nucleotide polymorphisms (SNPs) in candidate genes previously reported to decrease EFV (rs3745274, rs35303484, rs35979566 in CYP2B6) and LPV/r clearance (rs4149056 in SLCO1B1, rs6945984 in CYP3A, rs717620 in ABCC2). Viral suppression was defined as having HIV-1 RNA <400 copies/ml throughout the study period. RESULTS: From January 2003 until May 2009, 37 individuals on EFV (28 suppressed and 9 not suppressed) and 69 on LPV/r (38 suppressed and 31 not suppressed) were eligible. The poor adherence period was a median of 32 weeks with 18.9% of EFV and 20.3% of LPV/r patients reporting missed doses on a daily basis. The tested SNPs were not determinant for viral suppression. Reporting missing >1 dose/week was associated with a lower probability of viral suppression compared to missing 1 dose/week (EFV: odds ratio (OR) 0.11, 95% confidence interval (CI): 0.01-0.99; LPV/r: OR 0.29, 95% CI: 0.09-0.94). In both groups, the probability of remaining suppressed increased with the duration of continuous suppression prior to the poor adherence period (EFV: OR 3.40, 95% CI: 0.62-18.75; LPV/r: OR 5.65, 95% CI: 1.82-17.56). CONCLUSIONS: The investigated genetic variants did not play a significant role in the sustained viral suppression of individuals with suboptimal adherence. Risk of failure decreased with longer duration of viral suppression in this population.

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Study design:Cross-sectional validation study.Objectives:To develop and validate a self-report version of the Spinal Cord Independence Measure (SCIM III).Setting:Two SCI rehabilitation facilities in Switzerland.Methods:SCIM III comprises 19 questions on daily tasks with a total score between 0 and 100 and subscales for 'self-care', 'respiration & sphincter management' and 'mobility'. A self-report version (SCIM-SR) was developed by expert discussions and pretests in individuals with spinal cord injury (SCI) using a German translation. A convenience sample of 99 inpatients with SCI was recruited. SCIM-SR data were analyzed together with SCIM III data obtained from attending health professionals.Results:High correlations between SCIM III and SCIM-SR were observed. Pearson's r for the total score was 0.87 (95% confidence interval (CI) 0.82-0.91), for the subscales self-care 0.87 (0.81-0.91); respiration & sphincter management 0.81 (0.73-0.87); and mobility 0.87 (0.82-0.91). Intraclass correlations were: total score 0.90 (95% CI 0.85-0.93); self-care 0.86 (0.79-0.90); respiration & sphincter management 0.80 (0.71-0.86); and mobility 0.83 (0.76-0.89). Bland-Altman plots showed that patients rated their functioning higher than professionals, in particular for mobility. The mean difference between SCIM-SR and SCIM III for the total score was 5.14 (point estimate 95% CI 2.95-7.34), self-care 0.89 (0.19-1.59), respiration & sphincter management 1.05 (0.18-2.28 ) and mobility 3.49 (2.44-4.54). Particularly patients readmitted because of pressure sores rated their independence higher than attending professionals.Conclusion:Our results support the criterion validity of SCIM-SR. The self-report version may facilitate long-term evaluations of independence in persons with SCI in their home situation.

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Aims and objectives  This study aimed to determine the discriminant validity and the test-retest reliability of a questionnaire testing the impact of evidence-based medicine (EBM) training on doctors' knowledge and skills. Methods  Questionnaires were sent electronically to all doctors working as residents and chief residents in two French speaking hospital networks in Switzerland. Participants completed the questionnaire twice, within a 4-week interval. The discriminant validity was examined in comparing doctors' performance according to their reported EBM previous training. Proportion of agreement between both sessions of the questionnaire, Cohen's kappa and 'uniform kappa' determined its test-retest reliability. Results  The participation rate was 9.8%/7.1% to first/second session. Performance increased according to the level of doctors' previous training in EBM. The observed proportion of agreement between both sessions was over 70% for 14/19 questions, and the 'uniform kappa' was superior to 0.60 for 15/19 questions. Conclusion  The discriminant validity and test-retest reliability of the questionnaire were satisfying. The low participation rate did not prevent the study from achieving its aims.

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Self‐selection into treatment and self‐selection into the sample are major concerns of VAA research and need to be controlled for if the aim is to deduce causal effects from VAA use in observational data. This paper focuses on the methodological aspects of VAA research and outlines omnipresent endogeneity issues, partly imposed through unobserved factors that affect both whether individuals chose to use VAAs and their electoral behavior. We promote using Heckman selection models and apply various versions of the model to data from the Swiss electorate and smartvote users in order to see to what extent selection biases interfere with the estimated effects of interest.

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Introduction: Neuroimaging of the self focused on high-level mechanisms such as language, memory or imagery of the self. Recent evidence suggests that low-level mechanisms of multisensory and sensorimotor integration may play a fundamental role in encoding self-location and the first-person perspective (Blanke and Metzinger, 2009). Neurological patients with out-of body experiences (OBE) suffer from abnormal self-location and the first-person perspective due to a damage in the temporo-parietal junction (Blanke et al., 2004). Although self-location and the first-person perspective can be studied experimentally (Lenggenhager et al., 2009), the neural underpinnings of self-location have yet to be investigated. To investigate the brain network involved in self-location and first-person perspective we used visuo-tactile multisensory conflict, magnetic resonance (MR)-compatible robotics, and fMRI in study 1, and lesion analysis in a sample of 9 patients with OBE due to focal brain damage in study 2. Methods: Twenty-two participants saw a video showing either a person's back or an empty room being stroked (visual stimuli) while the MR-compatible robotic device stroked their back (tactile stimulation). Direction and speed of the seen stroking could either correspond (synchronous) or not (asynchronous) to those of the seen stroking. Each run comprised the four conditions according to a 2x2 factorial design with Object (Body, No-Body) and Synchrony (Synchronous, Asynchronous) as main factors. Self-location was estimated using the mental ball dropping (MBD; Lenggenhager et al., 2009). After the fMRI session participants completed a 6-item adapted from the original questionnaire created by Botvinick and Cohen (1998) and based on questions and data obtained by Lenggenhager et al. (2007, 2009). They were also asked to complete a questionnaire to disclose the perspective they adopted during the illusion. Response times (RTs) for the MBD and fMRI data were analyzed with a 3-way mixed model ANOVA with the in-between factor Perspective (up, down) and the two with-in factors Object (body, no-body) and Stroking (synchronous, asynchronous). Quantitative lesion analysis was performed using MRIcron (Rorden et al., 2007). We compared the distributions of brain lesions confirmed by multimodality imaging (Knowlton, 2004) in patients with OBE with those showing complex visual hallucinations involving people or faces, but without any disturbance of self-location and first person perspective. Nine patients with OBE were investigated. The control group comprised 8 patients. Structural imaging data were available for normalization and co-registration in all the patients. Normalization of each patient's lesion into the common MNI (Montreal Neurological Institute) reference space permitted simple, voxel-wise, algebraic comparisons to be made. Results: Even if in the scanner all participants were lying on their back and were facing upwards, analysis of perspective showed that half of the participants had the impression to be looking down at the virtual human body below them, despite any cues about their body position (Down-group). The other participants had the impression to be looking up at the virtual body above them (Up-group). Analysis of Q3 ("How strong was the feeling that the body you saw was you?") indicated stronger self-identification with the virtual body during the synchronous stroking. RTs in the MBD task confirmed these subjective data (significant 3-way interaction between perspective, object and stroking). fMRI results showed eight cortical regions where the BOLD signal was significantly different during at least one of the conditions resulting from the combination of Object and Stroking, relative to baseline: right and left temporo-parietal junction, right EBA, left middle occipito-temporal gyrus, left postcentral gyrus, right medial parietal lobe, bilateral medial occipital lobe (Fig 1). The activation patterns in right and left temporo-parietal junction and right EBA reflected changes in self-location and perspective as revealed by statistical analysis that was performed on the percentage of BOLD change with respect to the baseline. Statistical lesion overlap comparison (using nonparametric voxel based lesion symptom mapping) with respect to the control group revealed the right temporo-parietal junction, centered at the angular gyrus (Talairach coordinates x = 54, y =-52, z = 26; p>0.05, FDR corrected). Conclusions: The present questionnaire and behavioural results show that - despite the noisy and constraining MR environment) our participants had predictable changes in self-location, self-identification, and first-person perspective when robotic tactile stroking was applied synchronously with the robotic visual stroking. fMRI data in healthy participants and lesion data in patients with abnormal self-location and first-person perspective jointly revealed that the temporo-parietal cortex especially in the right hemisphere encodes these conscious experiences. We argue that temporo-parietal activity reflects the experience of the conscious "I" as embodied and localized within bodily space.

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Neuroimaging of the self has focused on high-level mechanisms such as language, memory or imagery of the self and implicated widely distributed brain networks. Yet recent evidence suggests that low-level mechanisms such as multisensory and sensorimotor integration may play a fundamental role in self-related processing. In the present study we used visuotactile multisensory conflict, robotics, virtual reality, and fMRI to study such low-level mechanisms by experimentally inducing changes in self-location. Participants saw a video of a person's back (body) or an empty room (no-body) being stroked while a MR-compatible robotic device stroked their back. The latter tactile input was synchronous or asynchronous with respect to the seen stroking. Self-location was estimated behaviorally confirming previous data that self-location only differed between the two body conditions. fMRI results showed a bilateral activation of the temporo-parietal cortex with a significantly higher BOLD signal increase in the synchronous/body condition with respect to the other conditions. Sensorimotor cortex and extrastriate-body-area were also activated. We argue that temporo-parietal activity reflects the experience of the conscious 'I' as embodied and localized within bodily space, compatible with clinical data in neurological patients with out-of-body experiences.

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The glioma CpG island methylator phenotype (G-CIMP) has been shown to be highly correlated with prognosis andwas noted to be highly concordant with IDH1mutation in malignant glioma in the limited number of samples analyzed. To better understand the relationship of G-CIMP with IDH1 mutation status and patient outcome, we examined G-CIMP status in detail in a larger retrospective series of glioblastomas as well as tumor samples from the RTOG 0525 clinical trial. Sampleswere tested for 6 CIMPmarkers andwere correlated with patient outcomes. In the retrospective tumor set (n ¼ 301),we found 3 distinct survival groups based on the number of CIMP markers: 0-1 (CIMP-negative), 2-4 (CIMP-intermediate), and 5 or greater (CIMP-positive) with median survivals 13.8, 20.1, and 90.6 months, respectively. This finding was validated in the RTOG 0525 samples (median survivals 15.0, 20.3, and 37.0 months). Among 787 cases with both IDH and CIMP data, 617 were CIMP-negative, 136 were CIMP-intermediate, and 34 were CIMP-positive. Seven hundred forty-four were wild type for IDH1 mutation, and 43 were mutant. CIMP and IDH status were positively correlated but outliers were found. Among the 610 CIMP-negative tumors, there were 7 IDH-mutant tumors, which showed no difference in outcome. Similarly, among the 34 CIMP-positive tumors, there were 21 IDH-mutant cases, which also showed no difference in outcome. However, among the CIMP-intermediate cases, there were 15 IDH-mutant cases with significantly (p ¼ 0.0003) improved outcome (medians not reached vs. 18.5 months, 2 year survival 87% vs. 32%). Multivariate analysis showed that both IDH1 mutation status and CIMP status were independent predictors of outcome. These findings suggest the clinical utility of refining the CIMP status into negative, intermediate, and positive groups and the finding that both IDH1 and CIMPstatus are important molecular markers in GBM.

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Self-potentials (SP) are sensitive to water fluxes and concentration gradients in both saturated and unsaturated geological media, but quantitative interpretations of SP field data may often be hindered by the superposition of different source contributions and time-varying electrode potentials. Self-potential mapping and close to two months of SP monitoring on a gravel bar were performed to investigate the origins of SP signals at a restored river section of the Thur River in northeastern Switzerland. The SP mapping and subsequent inversion of the data indicate that the SP sources are mainly located in the upper few meters in regions of soil cover rather than bare gravel. Wavelet analyses of the time-series indicate a strong, but non-linear influence of water table and water content variations, as well as rainfall intensity on the recorded SP signals. Modeling of the SP response with respect to an increase in the water table elevation and precipitation indicate that the distribution of soil properties in the vadose zone has a very strong influence. We conclude that the observed SP responses on the gravel bar are more complicated than previously proposed semi-empiric relationships between SP signals and hydraulic head or the thickness of the vadose zone. We suggest that future SP monitoring in restored river corridors should either focus on quantifying vadose zone processes by installing vertical profiles of closely spaced SP electrodes or by installing the electrodes within the river to avoid signals arising from vadose zone processes and time-varying electrochemical conditions in the vicinity of the electrodes.

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The antioxidant enzyme peroxiredoxin 6 (Prdx6) is a key regulator of the cellular redox balance, particularly under stress conditions. We identified Prdx6 as an important player in different phases of skin carcinogenesis. Loss of Prdx6 in mice enhanced the susceptibility to skin tumorigenesis, whereas overexpression of Prdx6 in keratinocytes of transgenic mice had the opposite effect. The tumor-preventive effect of Prdx6, which was observed in a human papilloma virus 8-induced and a chemically induced tumor model, was not due to alterations in keratinocyte proliferation, apoptosis, or in the inflammatory response. Rather, endogenous and overexpressed Prdx6 reduced oxidative stress as reflected by the lower levels of oxidized phospholipids in the protumorigenic skin of Prdx6 transgenic mice and the higher levels in Prdx6-knockout mice than in control animals. In contrast to its beneficial effect in tumor prevention, overexpression of Prdx6 led to an acceleration of malignant progression of existing tumors, revealing a dual function of this enzyme in the pathogenesis of skin cancer. Finally, we found strong expression of PRDX6 in keratinocytes of normal human skin and in the tumor cells of squamous cell carcinomas, indicating a role of Prdx6 in human skin carcinogenesis. Taken together, our data point to the potential usefulness of Prdx6 activators or inhibitors for controlling different stages of skin carcinogenesis.

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BACKGROUND: Thyroid ectopy results from the failure of the thyroid precursor cells to migrate from the primordial pharynx to the anterior part of the neck. Most ectopic thyroids are revealed by congenital hypothyroidism and present as a single round mass at the base of the tongue, with no other thyroid tissue. However, some cases have dual ectopy, with part of the tissue having partially migrated. We hypothesized that this occurs more frequently than previously reported.¦METHODS: To determine the prevalence of dual ectopy, we reviewed the pertechnetate scintigraphies of 81 patients with congenital hypothyroidism from thyroid ectopy diagnosed between 2002 and 2011 at our institution.¦RESULTS: We report a series of seven cases (9%) of dual ectopy, representing an incidence ranging from 1:50,000 to 1:70,000.¦CONCLUSIONS: Almost one in 10 cases with congenital hypothyroidism due to thyroid ectopy has dual ectopy. This suggests that two populations of cells diverged at an early stage of development, which may arise from insufficient signaling gradients in surrounding tissues during early organogenesis or may indirectly support the polyclonal nature of the thyroid.