No abstract

No abstract

No abstract

The risk of serious bleeding is a major liability of anticoagulant drugs that are active-site competitive inhibitors targeting the Factor Xa (FXa) prothrombin (PT) binding site. The present work identifies several new classes of small molecule anticoagulants that can act as nonactive site inhibitors of the prothrombinase (PTase) complex composed of FXa and Factor Va (FVa). These new classes of anticoagulants were identified, using a novel agnostic computational approach to identify previously unrecognized binding pockets at the FXa-FVa interface. From about three million docking calculations of 281,128 compounds in a conformational ensemble of FXa heavy chains identified by molecular dynamics (MD) simulations, 97 compounds and their structural analogues were selected for experimental validation, through a series of inhibition assays. The compound selection was based on their predicted binding affinities to FXa and their ability to successfully bind to multiple protein conformations while showing selectivity for particular binding sites at the FXa/FVa interface. From these, thirty-one (31) compounds were experimentally identified as nonactive site inhibitors. Concentration-based assays further identified 10 compounds represented by four small-molecule families of inhibitors that achieve dose-independent partial inhibition of PTase activity in a nonactive site-dependent and self-limiting mechanism. Several compounds were identified for their ability to bind to protein conformations only seen during MD, highlighting the importance of accounting for protein flexibility in structure-based drug discovery approaches.

Background Rapid decision-making with limited resources and prior research to draw upon posed challenges for health service leaders globally when preparing for COVID-19. How do health services prepare for a pandemic and evaluate if the preparation has been effective? This study aimed to explore health workers’ perceptions and knowledge regarding preparedness for COVID-19 at a regional health service in Australia. Methods A 32-item online survey was developed to evaluate preparedness across five scales: 1) Clinical, 2) Communication, 3) Environment, 4) Human Resources, and 5) General Preparedness. Data were analyzed using parametric and non-parametric statistics and qualitative content analysis. Results Ninety-three employees completed the survey, with most working in clinical roles (58.1%). Respondents largely felt the health service was well-prepared (84.0%) and they were personally prepared (74.4%) to respond to COVID-19. Clinical and communication scale scores varied by role type. Respondents faced personal risk and resource shortages impacted their sense of safety; others felt adequately supported. Conclusions A coordinated “whole hospital response”, accessible and inclusive communication, education, adequate resourcing, and employee wellbeing supports are necessary when preparing health services for sentinel events. This survey tool offers health services an approach to evaluating pandemic preparation. Continued advocacy for resources and wellbeing needs of health workers is paramount in future preparations.