Evaluation of a nudge intervention providing simple feedback to clinicians of the consequence of radiation exposure on demand for computed tomography: a controlled study

Computerised tomography (CT) is readily available in developed countries. As one of the side-effects includes an increased risk of cancer, interventions that may encourage more judicious use of CT scans are important. Behavioural economics theory includes the use of nudges that aim to help more informed decisions to be made, although these have been rarely used in hospitals to date. We aimed to evaluate the impact of a simple educational message appended to the CT scan report on subsequent numbers of CT scans completed using a controlled interrupted time series design based in two teaching hospitals in X. The intervention was the addition of a non-directional educational message on the risk of ionising radiation to all CT scan reports. There was a statistically significant reduction in the number of CT scans requested in the intervention hospital compared to the control hospital (-4.6%, 95% confidence intervals -7.4 to -1.7, p = 0.002) in the 12 months after the intervention was implemented. We conclude that a simple, non-directional nudge intervention has the capacity to modify clinician use of CT scans. This approach is cheap, and has potential in helping support doctors make informed decisions

In Vitro and In Vivo Characterization of the Alkaloid Nuciferine

RationaleThe sacred lotus (Nelumbo nucifera) contains many phytochemicals and has a history of human use. To determine which compounds may be responsible for reported psychotropic effects, we used in silico predictions of the identified phytochemicals. Nuciferine, an alkaloid component of Nelumbo nucifera and Nymphaea caerulea, had a predicted molecular profile similar to antipsychotic compounds. Our study characterizes nuciferine using in vitro and in vivo pharmacological assays.MethodsNuciferine was first characterized in silico using the similarity ensemble approach, and was followed by further characterization and validation using the Psychoactive Drug Screening Program of the National Institute of Mental Health. Nuciferine was then tested in vivo in the head-twitch response, pre-pulse inhibition, hyperlocomotor activity, and drug discrimination paradigms.ResultsNuciferine shares a receptor profile similar to aripiprazole-like antipsychotic drugs. Nuciferine was an antagonist at 5-HT2A, 5-HT2C, and 5-HT2B, an inverse agonist at 5-HT7, a partial agonist at D2, D5 and 5-HT6, an agonist at 5-HT1A and D4 receptors, and inhibited the dopamine transporter. In rodent models relevant to antipsychotic drug action, nuciferine blocked head-twitch responses and discriminative stimulus effects of a 5-HT2A agonist, substituted for clozapine discriminative stimulus, enhanced amphetamine induced locomotor activity, inhibited phencyclidine (PCP)-induced locomotor activity, and rescued PCP-induced disruption of prepulse inhibition without induction of catalepsy.ConclusionsThe molecular profile of nuciferine was similar but not identical to that shared with several approved antipsychotic drugs suggesting that nuciferine has atypical antipsychotic-like actions

Structural basis of the filamin A actin-binding domain interaction with F-actin

Cryo-EM reconstructions were deposited in the Electron Microscopy Data Bank with the following accession numbers: F20-F-actin-FLNaABD, EMD-7833; F20-F-actin-FLNaABD-Q170P, EMD-7832; F20-F-actin-FLNaABD-E254K, EMD-8918; Krios-F-actin-FLNaABD-E254K, EMD-7831. The corresponding FLNaABD-E254K filament model was deposited in the PDB with accession number 6D8C. Source data for F-actin-targeting analyses (Figs. 2c,d,g,h, 3b,c,e,f, 4d,e, 5c,d, and 6a,b) and co-sedimentation assays (Figs. 5g and 6d) are available with the paper online. Other data are available from the corresponding author upon reasonable request. We thank Z. Razinia for generating numerous FLNa constructs, S. Wu for expertise in using the Krios microscope, J. Lees for advice on model refinement, and M. Lemmon for helpful comments in preparing the manuscript. We also thank the Yale Center for Research Computing for guidance and use of the Farnam Cluster, as well as the staff at the YMS Center for Molecular Imaging for the use of the EM Core Facility. This work was funded by grants from the National Institutes of Health (R01-GM068600 (D.A.C.), R01-NS093704 (D.A.C.), R37-GM057247 (C.V.S.), R01-GM110530 (C.V.S.), T32-GM007324, T32-GM008283) and an award from American Heart Association (15PRE25700119 (D.V.I.)).Peer reviewedPostprin

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

The nature of the Syntaxin4 C-terminus affects Munc18c-supported SNARE assembly

Vesicular transport of cellular cargo requires targeted membrane fusion and formation of a SNARE protein complex that draws the two apposing fusing membranes together. Insulin-regulated delivery and fusion of glucose transporter-4 storage vesicles at the cell surface is dependent on two key proteins: the SNARE integral membrane protein Syntaxin4 (Sx4) and the soluble regulatory protein Munc18c. Many reported in vitro studies of Munc18c:Sx4 interactions and of SNARE complex formation have used soluble Sx4 constructs lacking the native transmembrane domain. As a consequence, the importance of the Sx4 C-terminal anchor remains poorly understood. Here we show that soluble C-terminally truncated Sx4 dissociates more rapidly from Munc18c than Sx4 where the C-terminal transmembrane domain is replaced with a T4-lysozyme fusion. We also show that Munc18c appears to inhibit SNARE complex formation when soluble C-terminally truncated Sx4 is used but does not inhibit SNARE complex formation when Sx4 is C-terminally anchored (by a C-terminal His-tag bound to resin, by a C-terminal T4L fusion or by the native C-terminal transmembrane domain in detergent micelles). We conclude that the C-terminus of Sx4 is critical for its interaction with Munc18c, and that the reported inhibitory role of Munc18c may be an artifact of experimental design. These results support the notion that a primary role of Munc18c is to support SNARE complex formation and membrane fusion

Kinetics of Munc18c interaction with Sx4 in solution.

<p><b>a.</b> Time course of complex formation of Alexa488-labeled Sx4_1-275-His (50 nM) with HMunc18c at various concentrations: 100 nM (black curve), 200 nM (green curve), 300 nM (blue curve), 400 nM (pink curve), 1000 nM (red curve), 1500 nM (grey curve), 2000 nM (magenta curve) and 2500 nM (cyan curve). Solid lines represent global fits to titration data in the Dynafit 4.0 program. Resulting kinetic constants are shown in the graph inset <b>b</b>. As for <b>a</b>. except that formation of HMunc18c:Sx4_1-275-T4L-His was monitored. Concentrations of HMunc18c used were: 100 nM (black curve), 200 nM (green curve), 400 nM (blue curve), 600 nm (pink curve), 800 nM (red curve), 1000 nM (magenta curve), 1500 nM (gray curve).</p

Summary of kinetic data for the Munc18c-Syntaxin4 interaction.

<p>Values shown for the bio-layer interferometry experiments are mean ± s.d. where each experiment was repeated at least three times. Values and standard errors are shown for the fluorescence anisotropy experiments and these were obtained from a global fit to multiple kinetic data sets with differing concentrations of Munc18c. Bold text indicates dissociation rate constants (k_off) for Munc18c-Sx4_1-275 where Sx4_1-275 is free in solution.</p

Munc18c does not block SNARE assembly when the Sx4 C-terminus is immobilized.

<p>Coomassie Blue stained SDS-PAGE analysis of the binding of SNAP23 and VAMP2 to Sx4 proteins (Sx4_1-275-His or Sx4_1-275-T4L-His) immobilized on Co²⁺resin by their C-terminus. Immobilized Sx4 proteins were complexed with Munc18c (de-tagged) prior to overnight incubation with SNAP23 and VAMP2. C-terminally immobilized Sx4 proteins were able to pull down SNARE partners (SNAP23 and VAMP2) in the presence of Munc18c (lanes labeled Assembly) and in the absence of Munc18c (lanes labeled Controls). Lanes labeled INPUTS show the protein samples used in the experiments. The control lane labeled Munc18c is a negative control showing the lack of interaction of Munc18c with beads. The gel displayed is representative of three replicate experiments. Solid vertical lines on the gel image indicate the removal of intervening lanes or where two different gels have been placed adjacent to each other.</p