39 research outputs found

    Simulation vs. Reality: A Comparison of In Silico Distance Predictions with DEER and FRET Measurements

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    Site specific incorporation of molecular probes such as fluorescent- and nitroxide spin-labels into biomolecules, and subsequent analysis by Förster resonance energy transfer (FRET) and double electron-electron resonance (DEER) can elucidate the distance and distance-changes between the probes. However, the probes have an intrinsic conformational flexibility due to the linker by which they are conjugated to the biomolecule. This property minimizes the influence of the label side chain on the structure of the target molecule, but complicates the direct correlation of the experimental inter-label distances with the macromolecular structure or changes thereof. Simulation methods that account for the conformational flexibility and orientation of the probe(s) can be helpful in overcoming this problem. We performed distance measurements using FRET and DEER and explored different simulation techniques to predict inter-label distances using the Rpo4/7 stalk module of the M. jannaschii RNA polymerase. This is a suitable model system because it is rigid and a high-resolution X-ray structure is available. The conformations of the fluorescent labels and nitroxide spin labels on Rpo4/7 were modeled using in vacuo molecular dynamics simulations (MD) and a stochastic Monte Carlo sampling approach. For the nitroxide probes we also performed MD simulations with explicit water and carried out a rotamer library analysis. Our results show that the Monte Carlo simulations are in better agreement with experiments than the MD simulations and the rotamer library approach results in plausible distance predictions. Because the latter is the least computationally demanding of the methods we have explored, and is readily available to many researchers, it prevails as the method of choice for the interpretation of DEER distance distributions

    Landiolol in patients with septic shock resident in an intensive care unit (LANDI-SEP): study protocol for a randomized controlled trial

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    In patients with septic shock, the presence of an elevated heart rate (HR) after fluid resuscitation marks a subgroup of patients with a particularly poor prognosis. Several studies have shown that HR control in this population is safe and can potentially improve outcomes. However, all were conducted in a single-center setting. The aim of this multicenter study is to demonstrate that administration of the highly beta1-selective and ultrashort-acting beta blocker landiolol in patients with septic shock and persistent tachycardia (HR ae 95 beats per minute [bpm]) is effective in reducing and maintaining HR without increasing vasopressor requirements. A phase IV, multicenter, prospective, randomized, open-label, controlled study is being conducted. The study will enroll a total of 200 patients with septic shock as defined by The Third International Consensus Definitions for Sepsis and Septic Shock criteria and tachycardia (HR ae 95 bpm) despite a hemodynamic optimization period of 24-36 h. Patients are randomized (1:1) to receive either standard treatment (according to the Surviving Sepsis Campaign Guidelines 2016) and continuous landiolol infusion to reach a target HR of 80-94 bpm or standard treatment alone. The primary endpoint is HR response (HR 80-94 bpm), the maintenance thereof, and the absence of increased vasopressor requirements during the first 24 h after initiating treatment. Despite recent studies, the role of beta blockers in the treatment of patients with septic shock remains unclear. This study will investigate whether HR control using landiolol is safe, feasible, and effective, and further enhance the understanding of beta blockade in patients with septic shock

    Sex differences modulating serotonergic polymorphisms implicated in the mechanistic pathways of risk for depression and related disorders:

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137310/1/jnr23877.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137310/2/jnr23877_am.pd

    Statistik als Instrument der empirischen Wirtschafts- und Sozialforschung - Eine methodologische Betrachtung aus der Sicht der Frankfurter Schule der sozialwissenschaftlichen Statistik

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    In the first part the history of the ideas of the Frankfurt School of statistics is presented. In the second part the function of statistics within the process of gaining empirical knowledge by economic and social research is systematically analysed. An essential is the distinction between the theoretical, political and institutional dimension on the one hand and the statistical one on the other. For each application in economy und society on optimal adequacy between the theoretical, political and institutional concepts and the statistical definitions and methods is necessary as well as a critical and competent interpretation of the results to make them suitable for well-founded theoretical or political decisions.History of statistics, social and economic statistics, theory of knowledge, adequacy, price indices

    Von der Volkszählung zum Registerzensus: Paradigmenwechsel in der deutschen amtlichen Statistik

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    Volkszählung, Registerzensus, Amtliche Statistik, Volkszählungsurteil, Testerhebungen,
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