89 research outputs found

    Embolie pulmonaire à l’ère du choosing wisely [Pulmonary embolism in the era of choosing wisely]

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    The emergence of new management rules and algorithms for suspected pulmonary embolism (PE) allows clinicians to limit certain additional examinations. The PERC rule can « rule-out » PE without complementary investigation. The revised Geneva and Wells scores, the YEARS algorithm, the use of age-adjusted D-dimers, and D-dimers adjusted to clinical probability can all reduce the need for CT scan. Finally, PESI and HESTIA provide help to choose which patient is eligible to be treated as out-patient

    An indicator of sudden cardiac death during brief coronary occlusion: electrocardiogram QT time and the role of collaterals

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    Aims The coronary collateral circulation has a beneficial role regarding all-cause and cardiac mortality. Hitherto, the underlying mechanism has not been clarified. The aim of this prospective study was to assess the effect of the coronary collateral circulation on electrocardiogram (ECG) QTc time change during short-term myocardial ischaemia. Methods and results A total of 150 patients (mean age 63 ± 11 years, 38 women) were prospectively included in this study. An ECG was recorded at baseline and during a standardized 1 min coronary balloon occlusion. QT interval was measured before, during, and after balloon occlusion and was corrected for heart rate (QTc). Simultaneously obtained collateral flow index (CFI), expressing collateral flow relative to normal anterograde flow, was determined based on intracoronary pressure measurements. During occlusion of the left anterior descending coronary artery mean QTc interval increased from 422 ± 33 to 439 ± 36 ms (P < 0.001), left circumflex occlusion led to an increase from 414 ± 32 to 427 ± 27 ms (P < 0.001). QTc was not influenced by occlusion of the right coronary artery (RCA) (417 ± 35 and 415 ± 34 ms, respectively; P = 0.863). QTc change during occlusion of the left coronary artery was inversely correlated with CFI (R2 = 0.122, P = 0.0002). Conclusion Myocardial ischaemia leads to QT prolongation during a controlled 1 min occlusion of the left, but not the RCA. QT prolongation is inversely related to collateral function indicating a protective mechanism of human coronary collaterals against cardiac deat

    Association of genetic risk scores with body mass index in Swiss psychiatric cohorts.

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    OBJECTIVE: Weight gain is associated with psychiatric disorders and/or with psychotropic drug treatments. We analyzed in three psychiatric cohorts under psychotropic treatment the association of weighted genetic risk scores (w-GRSs) with BMI by integrating BMI-related polymorphisms from the candidate-gene approach and Genome-Wide Association Studies (GWAS). MATERIALS AND METHODS: w-GRS of 32 polymorphisms associated previously with BMI in general population GWAS and 20 polymorphisms associated with antipsychotics-induced weight gain were investigated in three independent psychiatric samples. RESULTS: w-GRS of 32 polymorphisms were significantly associated with BMI in the psychiatric sample 1 (n=425) and were replicated in another sample (n=177). Those at the percentile 95 (p95) of the score had 2.26 and 2.99 kg/m higher predicted BMI compared with individuals at the percentile 5 (p5) in sample 1 and in sample 3 (P=0.009 and 0.04, respectively). When combining all samples together (n=750), a significant difference of 1.89 kg/m predicted BMI was found between p95 and p5 individuals at 12 months of treatment. Stronger associations were found among men (difference: 2.91 kg/m of predicted BMI between p95 and p5, P=0.0002), whereas no association was found among women. w-GRS of 20 polymorphisms was not associated with BMI. The w-GRS of 52 polymorphisms and the clinical variables (age, sex, treatment) explained 1.99 and 3.15%, respectively, of BMI variability. CONCLUSION: The present study replicated in psychiatric cohorts previously identified BMI risk variants obtained in GWAS analyses from population-based samples. Sex-specific analysis should be considered in further analysis

    Geometric Phases and Multiple Degeneracies in Harmonic Resonators

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    In a recent experiment Lauber et al. have deformed cyclically a microwave resonator and have measured the adiabatic normal-mode wavefunctions for each shape along the path of deformation. The nontrivial observed cyclic phases around a 3-fold degeneracy were accounted for by Manolopoulos and Child within an approximate theory. However, open-path geometrical phases disagree with experiment. By solving exactly the problem, we find unsuspected extra degeneracies around the multiple one that account for the measured phase changes throughout the path. It turns out that proliferation of additional degeneracies around a multiple one is a common feature of quantum mechanics.Comment: 4 pages, 4 figures. Accepted in Phys. Rev. Let

    Prediction of early weight gain during psychotropic treatment using a combinatorial model with clinical and genetic markers.

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    Psychotropic drugs can induce significant (&gt;5%) weight gain (WG) already after 1 month of treatment, which is a good predictor for major WG at 3 and 12 months. The large interindividual variability of drug-induced WG can be explained in part by genetic and clinical factors. The aim of this study was to determine whether extensive analysis of genes, in addition to clinical factors, can improve prediction of patients at risk for more than 5% WG at 1 month of treatment. Data were obtained from a 1-year naturalistic longitudinal study, with weight monitoring during weight-inducing psychotropic treatment. A total of 248 Caucasian psychiatric patients, with at least baseline and 1-month weight measures, and with compliance ascertained were included. Results were tested for replication in a second cohort including 32 patients. Age and baseline BMI were associated significantly with strong WG. The area under the curve (AUC) of the final model including genetic (18 genes) and clinical variables was significantly greater than that of the model including clinical variables only (AUCfinal: 0.92, AUCclinical: 0.75, P&lt;0.0001). Predicted accuracy increased by 17% with genetic markers (Accuracyfinal: 87%), indicating that six patients must be genotyped to avoid one misclassified patient. The validity of the final model was confirmed in a replication cohort. Patients predicted before treatment as having more than 5% WG after 1 month of treatment had 4.4% more WG over 1 year than patients predicted to have up to 5% WG (P≤0.0001). These results may help to implement genetic testing before starting psychotropic drug treatment to identify patients at risk of important WG

    Off-Diagonal Geometric Phases

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    We investigate the adiabatic evolution of a set of non-degenerate eigenstates of a parameterized Hamiltonian. Their relative phase change can be related to geometric measurable quantities that extend the familiar concept of Berry phase to the evolution of more than one state. We present several physical systems where these concepts can be applied, including an experiment on microwave cavities for which off-diagonal phases can be determined from published data.Comment: 5 pages 2 figures - RevTeX. Revised version including geometrical interpretatio

    Enhanced Electron Pairing in a Lattice of Berry Phase Molecules

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    We show that electron hopping in a lattice of molecules possessing a Berry phase naturally leads to pairing. Our building block is a simple molecular site model inspired by C60_{60}, but realized in closer similarity with Na3_3. In the resulting model electron hopping must be accompanied by orbital operators, whose function is to switch on and off the Berry phase as the electron number changes. The effective hamiltonians (electron-rotor and electron-pseudospin) obtained in this way are then shown to exhibit a strong pairing phenomenon, by means of 1D linear chain case studies. This emerges naturally from numerical studies of small NN-site rings, as well as from a BCS-like mean-field theory formulation. The pairing may be explained as resulting from the exchange of singlet pairs of orbital excitations, and is intimately connected with the extra degeneracy implied by the Berry phase when the electron number is odd. The relevance of this model to fullerides, to other molecular superconductors, as well as to present and future experiments, is discussed.Comment: 30 pages, RevTe

    Optical Holonomic Quantum Computer

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    In this paper the idea of holonomic quantum computation is realized within quantum optics. In a non-linear Kerr medium the degenerate states of laser beams are interpreted as qubits. Displacing devices, squeezing devices and interferometers provide the classical control parameter space where the adiabatic loops are performed. This results into logical gates acting on the states of the combined degenerate subspaces of the lasers, producing any one qubit rotations and interactions between any two qubits. Issues such as universality, complexity and scalability are addressed and several steps are taken towards the physical implementation of this model.Comment: 16 pages, 3 figures, REVTE

    Identification of four novel loci associated with psychotropic drug-induced weight gain in a Swiss psychiatric longitudinal study: A GWAS analysis.

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    Patients suffering from mental disorders are at high risk of developing cardiovascular diseases, leading to a reduction in life expectancy. Genetic variants can display greater influence on cardiometabolic features in psychiatric cohorts compared to the general population. The difference is possibly due to an intricate interaction between the mental disorder or the medications used to treat it and metabolic regulations. Previous genome wide association studies (GWAS) on antipsychotic-induced weight gain included a low number of participants and/or were restricted to patients taking one specific antipsychotic. We conducted a GWAS of the evolution of body mass index (BMI) during early (i.e., ≤ 6) months of treatment with psychotropic medications inducing metabolic disturbances (i.e., antipsychotics, mood stabilizers and some antidepressants) in 1135 patients from the PsyMetab cohort. Six highly correlated BMI phenotypes (i.e., BMI change and BMI slope after distinct durations of psychotropic treatment) were considered in the analyses. Our results showed that four novel loci were associated with altered BMI upon treatment at genome-wide significance (p &lt; 5 × 10 &lt;sup&gt;-8&lt;/sup&gt; ): rs7736552 (near MAN2A1), rs11074029 (in SLCO3A1), rs117496040 (near DEFB1) and rs7647863 (in IQSEC1). Associations between the four loci and alternative BMI-change phenotypes showed consistent effects. Replication analyses in 1622 UK Biobank participants under psychotropic treatment showed a consistent association between rs7736552 and BMI slope (p = 0.017). These findings provide new insights into metabolic side effects induced by psychotropic drugs and underline the need for future studies to replicate these associations in larger cohorts

    Associations Between High Plasma Methylxanthine Levels, Sleep Disorders and Polygenic Risk Scores of Caffeine Consumption or Sleep Duration in a Swiss Psychiatric Cohort.

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    Objective: We first sought to examine the relationship between plasma levels of methylxanthines (caffeine and its metabolites) and sleep disorders, and secondarily between polygenic risk scores (PRS) of caffeine consumption or sleep duration with methylxanthine plasma levels and/or sleep disorders in a psychiatric cohort. Methods: Plasma levels of methylxanthines were quantified by ultra-high performance liquid chromatography/tandem mass spectrometry. In inpatients, sleep disorder diagnosis was defined using ICD-10 "F51.0," sedative drug intake before bedtime, or hospital discharge letters, while a subgroup of sedative drugs was used for outpatients. The PRS of coffee consumption and sleep duration were constructed using publicly available GWAS results from the UKBiobank. Results: 1,747 observations (1,060 patients) were included (50.3% of observations with sleep disorders). Multivariate analyses adjusted for age, sex, body mass index, setting of care and psychiatric diagnoses showed that patients in the highest decile of plasma levels of methylxanthines had more than double the risk for sleep disorders compared to the lowest decile (OR = 2.13, p = 0.004). PRS of caffeine consumption was associated with plasma levels of caffeine, paraxanthine, theophylline and with their sum (β = 0.1; 0.11; 0.09; and 0.1, p &lt;sub&gt;corrected&lt;/sub&gt; = 0.01; 0.02; 0.02; and 0.01, respectively) but not with sleep disorders. A trend was found between the PRS of sleep duration and paraxanthine levels (β = 0.13, p &lt;sub&gt;corrected&lt;/sub&gt; = 0.09). Discussion: Very high caffeine consumption is associated with sleep disorders in psychiatric in- and outpatients. Future prospective studies should aim to determine the benefit of reducing caffeine consumption in high caffeine-consuming patients suffering from sleep disorders
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