93 research outputs found
Arterial hypertension in aortic valve stenosis: A critical update
Aortic stenosis (AS) is a very common valve disease and is associated with high mortality once it becomes symptomatic. Arterial hypertension (HT) has a high prevalence among patients with AS leading to worse left ventricle remodeling and faster degeneration of the valve. HT also interferes with the assessment of the severity of AS, leading to an underestimation of the real degree of stenosis. Treatment of HT in AS has not historically been pursued due to the fear of excess reduction in afterload without a possibility of increasing stroke volume due to the fixed aortic valve, but most recent evidence shows that several drugs are safe and effective in reducing BP in patients with HT and AS. RAAS inhibitors and beta‐blockers provide benefit in selected populations based on their profile of pharmacokinetics and pharmacodynamics. Different drugs, on the other hand, have proved to be unsafe, such as calcium channel blockers, or simply not easy enough to handle to be recommended in clinical practice, such as PDE5i, MRA or sodium nitroprusside. The present review highlights all available studies on HT and AS to guide antihypertensive treatment
Density dependence of the extinction coefficient of a dispersion of spherical metal particles
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Identification of a Photosystem II Phosphatase Involved in Light Acclimation in Arabidopsis
Reversible protein phosphorylation plays a major role in the acclimation of the photosynthetic apparatus to changes in light. Two paralogous kinases phosphorylate subsets of thylakoid membrane proteins. STN7 phosphorylates LHCII, the light harvesting antenna of photosystem II (PSII), to balance the activity of the two photosystems through state transitions. STN8, which is mainly involved in phosphorylation of PSII core subunits, influences folding of the thylakoid membranes and repair of PSII after photo-damage. The rapid reversibility of these acclimatory responses requires the action of protein phosphatases. In a reverse genetic screen we have identified the chloroplast PP2C phosphatase, PBCP (PHOTOSYSTEM II CORE PHOSPHATASE), which is required for efficient de-phosphorylation of PSII proteins. Its targets, identified by immunoblotting and mass spectrometry, largely coincide with those of the kinase STN8. The recombinant phosphatase is active in vitro on a synthetic substrate or on isolated thylakoids. Thylakoid folding is affected in the absence of PBCP, while its over-expression alters the kinetics of state transitions. PBCP and STN8 form an antagonistic kinase and phosphatase pair whose substrate specificity and physiological functions are distinct from those of STN7 and the counteracting phosphatase PPH1 (TAP38), but their activities may overlap to some degree
Treatment response to indacaterol/glycopyrronium versus salmeterol/fluticasone in exacerbating COPD patients by gender: a post-hoc analysis in the FLAME study
Background: The burden of chronic obstructive lung disease (COPD) is increasing in women, with recent evidence suggesting gender differences in disease characteristics and potentially in treatment outcomes. Methods: FLAME was a 52-week randomized controlled trial in patients with severe-to-very-severe COPD and a history of exacerbations. In this post-hoc analysis, gender-based baseline differences and treatment outcomes between indacaterol/glycopyrronium 110/50 μg once daily (IND/GLY) and salmeterol/fluticasone 50/500 twice daily (SFC) were assessed in terms of rate of exacerbations, time-to-first exacerbation, lung function, health status, and rescue medication use. Results: This post-hoc analysis included 2557 men and 805 women. Baseline characteristics differed between genders, with women being younger, having better lung function and more often experiencing ≥2 exacerbations in the previous year. Compared with SFC, IND/GLY treatment was associated with reductions in the annualized rates of moderate/severe exacerbations (rate ratio [95% CI]: 0.81 [0.73–0.91], 0.89 [0.74–1.07] in men and women, respectively). Similarly, time-to-first moderate/severe exacerbation was also delayed (hazard ratio [95% CI]: 0.79 [0. 70–0.89] and 0.76 [0.63–0.91] in men and women, respectively). Results were similar for all (mild/moderate/severe) exacerbations. Improvements in lung function, health status and rescue medication use with IND/GLY vs SFC were comparable between men and women. The smaller sample size for women may account for some observed discrepancies in treatment responses. Conclusions: Although there were gender differences in baseline characteristics, IND/GLY demonstrated similar trends for exacerbation prevention and lung function improvement in men and women with moderate-to-verysevere COPD and a history of exacerbations compared with SFC. Small differences in the effects seen between genders may be attributed to the different sizes of the two groups and need to be further evaluated in randomized trials that are appropriately powered for gender analysis. Trial registration: Post hoc analysis of the FLAME study. ClinicalTrials.gov number: NCT01782326. Registered 1 February 2013
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The sub-seasonal to seasonal prediction (S2S) project database
A database containing sub-seasonal to seasonal forecasts from 11 operational centres is available to the research community and will help advance our understanding of the sub-seasonal to seasonal time range.
Demands are growing rapidly in the operational prediction and applications communities for forecasts that fill the gap between medium-range weather and long-range or seasonal forecasts. Based on the potential for improved forecast skill at the sub-seasonal to seasonal time range, a sub-seasonal prediction (S2S) research project has been established by the World Weather Research Program/World Climate Research Program. A main deliverable of this project is the establishment of an extensive database, containing sub-seasonal (up to 60 days) forecasts, 3-weeks behind real-time, and reforecasts from 11 operational centers, modelled in part on the THORPEX Interactive Grand Global Ensemble (TIGGE) database for medium range forecasts (up to 15 days).
The S2S database, available to the research community since May 2015, represents an important tool to advance our understanding of the sub-seasonal to seasonal time range that has been considered for a long time as a “desert of predictability”. In particular, this database will help identify common successes and shortcomings in the model simulation and prediction of sources of sub-seasonal to seasonal predictability. For instance, a preliminary study suggests that the S2S models underestimate significantly the amplitude of the Madden Julian Oscillation (MJO) teleconnections over the Euro-Atlantic sector. The S2S database represents also an important tool for case studies of extreme events. For instance, a multi-model combination of S2S models displays higher probability of a landfall over Vanuatu islands 2 to 3 weeks before tropical cyclone Pam devastated the islands in March 2015
ePlant and the 3D Data Display Initiative: Integrative Systems Biology on the World Wide Web
Visualization tools for biological data are often limited in their ability to interactively integrate data at multiple scales. These computational tools are also typically limited by two-dimensional displays and programmatic implementations that require separate configurations for each of the user's computing devices and recompilation for functional expansion. Towards overcoming these limitations we have developed “ePlant” (http://bar.utoronto.ca/eplant) – a suite of open-source world wide web-based tools for the visualization of large-scale data sets from the model organism Arabidopsis thaliana. These tools display data spanning multiple biological scales on interactive three-dimensional models. Currently, ePlant consists of the following modules: a sequence conservation explorer that includes homology relationships and single nucleotide polymorphism data, a protein structure model explorer, a molecular interaction network explorer, a gene product subcellular localization explorer, and a gene expression pattern explorer. The ePlant's protein structure explorer module represents experimentally determined and theoretical structures covering >70% of the Arabidopsis proteome. The ePlant framework is accessed entirely through a web browser, and is therefore platform-independent. It can be applied to any model organism. To facilitate the development of three-dimensional displays of biological data on the world wide web we have established the “3D Data Display Initiative” (http://3ddi.org)
Biphasic Synaptic Ca Influx Arising from Compartmentalized Electrical Signals in Dendritic Spines
Dendritic spines compartmentalize synaptically-evoked biochemical signals. The authors show that electrical compartmentalization provided by a spine endows the associated synapse with additional modes of calcium signaling by shaping the kinetics of synaptic calcium currents
COVID-19 Vaccination in Pregnancy, Paediatrics, Immunocompromised Patients, and Persons with History of Allergy or Prior SARS-CoV-2 Infection: Overview of Current Recommendations and Pre- and Post-Marketing Evidence for Vaccine Efficacy and Safety
Nicotinic acetylcholine receptors in attention circuitry: the role of layer VI neurons of prefrontal cortex
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