Assessing the Impact of Cardiac Output and Valve Orientation on Bioprosthetic Pulmonary Valve Hemodynamics Using In Vitro 4D-Flow MRI and High-Speed Imaging.

Purpose: Pulmonary valve replacement (PVR) using bioprosthetic valves is a common procedure performed in patients with repaired Tetralogy of Fallot and other conditions, but these valves frequently become dysfunctional within 15 years of implantation. The causes for early valve failure are not clearly understood. The purpose of this study was to explore the impact of changing cardiac output (CO) and valve orientation on local hemodynamics and valve performance.

Sentinel Surveillance reveals phylogenetic diversity and detection of linear plasmids harboring and among enterococci collected in the United States.

and are frequent causes of healthcare-associated infections. Antimicrobial-resistant enterococci pose a serious public health threat, particularly vancomycin-resistant enterococci (VRE), for which treatment options are limited. The Centers for Disease Control and Prevention's Division of Healthcare Quality Promotion Sentinel Surveillance system conducted surveillance from 2018 to 2019 to evaluate antimicrobial susceptibility profiles and molecular epidemiology of 205 and 180 clinical isolates collected from nine geographically diverse sites in the United States.

Decolonization and Pathogen Reduction Approaches to Prevent Antimicrobial Resistance and Healthcare-Associated Infections.

Antimicrobial resistance in healthcare-associated bacterial pathogens and the infections they cause are major public health threats affecting nearly all healthcare facilities. Antimicrobial-resistant bacterial infections can occur when colonizing pathogenic bacteria that normally make up a small fraction of the human microbiota increase in number in response to clinical perturbations. Such infections are especially likely when pathogens are resistant to the collateral effects of antimicrobial agents that disrupt the human microbiome, resulting in loss of colonization resistance, a key host defense.

Comparison of carbapenem-susceptible and carbapenem-resistant at nine sites in the USA, 2013-2016: a resource for antimicrobial resistance investigators.

Carbapenem-resistant (CRE) are an urgent public health threat. Genomic sequencing is an important tool for investigating CRE. Through the Division of Healthcare Quality Promotion Sentinel Surveillance system, we collected CRE and carbapenem-susceptible (CSE) from nine clinical laboratories in the USA from 2013 to 2016 and analysed both phenotypic and genomic sequencing data for 680 isolates.

Antimicrobial Resistance Laboratory Network's multisite evaluation of the ThermoFisher Sensititre GN7F broth microdilution panel for antimicrobial susceptibility testing.

In 2017, the Centers for Disease Control and Prevention (CDC) established the Antimicrobial Resistance Laboratory Network to improve domestic detection of multidrug-resistant organisms. CDC and four laboratories evaluated a commercial broth microdilution panel. Antimicrobial susceptibility testing using the Sensititre GN7F (ThermoFisher Scientific, Lenexa, KS) was evaluated by testing 100 CDC and Food and Drug Administration AR Isolate Bank isolates [40 Enterobacterales (ENT), 30 (PSA), and 30 (ACB)].

Comparison of Immersed Boundary Simulations of Heart Valve Hemodynamics Against In Vitro 4D Flow MRI Data.

The immersed boundary (IB) method is a mathematical framework for fluid-structure interaction problems (FSI) that was originally developed to simulate flows around heart valves. Direct comparison of FSI simulations around heart valves against experimental data is challenging, however, due to the difficulty of performing robust and effective simulations, the complications of modeling a specific physical experiment, and the need to acquire experimental data that is directly comparable to simulation data. Such comparators are a necessary precursor for further formal validation studies of FSI simulations involving heart valves.

Development of a Broth Microdilution Method To Characterize Chlorhexidine MICs among Bacteria Collected from 2005 to 2019 at Three U.S. Sites.

Chlorhexidine bathing to prevent transmission of multidrug-resistant organisms has been adopted by many U.S. hospitals, but increasing chlorhexidine use has raised concerns about possible emergence of resistance.

Emerging issues in probiotic safety: 2023 perspectives.

Probiotics are used for both generally healthy consumers and in clinical settings. However, theoretical and proven adverse events from probiotic consumption exist. New probiotic strains and products, as well as expanding use of probiotics into vulnerable populations, warrants concise, and actionable recommendations on how to work toward their safe and effective use.

Reference Susceptibility Testing and Genomic Surveillance of Clostridioides difficile, United States, 2012-17.

Background: Antimicrobial susceptibility testing (AST) is not routinely performed for Clostridioides difficile and data evaluating minimum inhibitory concentrations (MICs) are limited. We performed AST and whole genome sequencing (WGS) for 593 C. difficile isolates collected between 2012 and 2017 through the Centers for Disease Control and Prevention's Emerging Infections Program.

Sentinel Surveillance Reveals Emerging Daptomycin-Resistant ST736 and Multiple Mechanisms of Linezolid Resistance in Enterococci in the United States.

and with resistance to daptomycin and/or linezolid are emerging globally. We present the genomic characterization of daptomycin- and linezolid-resistant and surveillance isolates from the United States, 2013-2016. Daptomycin resistance was low among (2/364, 0.

Molecular Characterization of Carbapenem-Resistant Enterobacterales Collected in the United States.

Carbapenem-resistant Enterobacterales (CRE) are a growing public health concern due to resistance to multiple antibiotics and potential to cause health care-associated infections with high mortality. Carbapenemase-producing CRE are of particular concern given that carbapenemase-encoding genes often are located on mobile genetic elements that may spread between different organisms and species. In this study, we performed phenotypic and genotypic characterization of CRE collected at eight U.

Detection and Characterization of Targeted Carbapenem-Resistant Health Care-Associated Threats: Findings from the Antibiotic Resistance Laboratory Network, 2017 to 2019.

Carbapenemase gene-positive (CP) Gram-negative bacilli are of significant clinical and public health concern. Their rapid detection and containment are critical to preventing their spread and additional infections they can cause. To this end, CDC developed the Antibiotic Resistance Laboratory Network (AR Lab Network), in which public health laboratories across all 50 states, several cities, and Puerto Rico characterize clinical isolates of carbapenem-resistant (CRE), Pseudomonas aeruginosa (CRPA), and Acinetobacter baumannii (CRAB) and conduct colonization screens to detect the presence of mobile carbapenemase genes.

Effects of Patient Characteristics on Diagnostic Performance of Self-Collected Samples for SARS-CoV-2 Testing.

We evaluated the performance of self-collected anterior nasal swab (ANS) and saliva samples compared with healthcare worker-collected nasopharyngeal swab specimens used to test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used the same PCR diagnostic panel to test all self-collected and healthcare worker-collected samples from participants at a public hospital in Atlanta, Georgia, USA. Among 1,076 participants, 51.

Framing Bacterial Genomics for Public Health (Care).

Advancements in comparative genomics have generated significant interest in defining applications for health care-associated pathogens. Clinical microbiology, however, relies on increasingly automated platforms to quickly identify pathogens, resistance mechanisms, and therapy options within Clinical Laboratory Improvement Amendments (CLIA)- and FDA-approved frameworks. Additionally, and most notably, health care-associated pathogens, especially those that are resistant to antibiotics, represent a diverse spectrum of genera harboring complex genetic targets, including antibiotic, biocide, and virulence determinants that can be highly transmissible and, at least for antibiotic resistance, serve as potential targets for containment efforts.

In Vitro Assessment of Right Ventricular Outflow Tract Anatomy and Valve Orientation Effects on Bioprosthetic Pulmonary Valve Hemodynamics.

Purpose: The congenital heart defect Tetralogy of Fallot (ToF) affects 1 in 2500 newborns annually in the US and typically requires surgical repair of the right ventricular outflow tract (RVOT) early in life, with variations in surgical technique leading to large disparities in RVOT anatomy among patients. Subsequently, often in adolescence or early adulthood, patients usually require surgical placement of a xenograft or allograft pulmonary valve prosthesis. Valve longevity is highly variable for reasons that remain poorly understood.

Assessing the in vitro impact of ceftazidime on aztreonam/avibactam susceptibility testing for highly resistant MBL-producing Enterobacterales.

Background: Aztreonam/avibactam is a combination agent that shows promise in treating infections caused by highly antibiotic-resistant MBL-producing Enterobacterales. This combination can be achieved by combining two FDA-approved drugs: ceftazidime/avibactam and aztreonam. It is unknown whether ceftazidime in the combination ceftazidime/aztreonam/avibactam has a synergistic or antagonistic effect on the in vitro activity of aztreonam/avibactam by significantly increasing or decreasing the MIC.

Coronavirus Disease 2019 (COVID-19) in Americans Aboard the Diamond Princess Cruise Ship.

Background: The Diamond Princess cruise ship was the site of a large outbreak of coronavirus disease 2019 (COVID-19). Of 437 Americans and their travel companions on the ship, 114 (26%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods: We interviewed 229 American passengers and crew after disembarkation following a ship-based quarantine to identify risk factors for infection and characterize transmission onboard the ship.

Validation of Aztreonam-Avibactam Susceptibility Testing Using Digitally Dispensed Custom Panels.

Aztreonam-avibactam is a combination antimicrobial agent with activity against carbapenemase-producing (CPE) with metallo-β-lactamases (MβLs). Although aztreonam-avibactam is not yet approved by the U.S.

Insular Microbiogeography: Three Pathogens as Exemplars.

Traditional taxonomy in biology assumes that life is organized in a simple tree. Attempts to classify microorganisms in this way in the genomics era led microbiologists to look for finite sets of 'core' genes that uniquely group taxa as clades in the tree. However, the diversity revealed by large-scale whole genome sequencing is calling into question the long-held model of a hierarchical tree of life, which leads to questioning of the definition of a species.

Effects of motion on MRI signal decay from micron-scale particles.

Transverse decay rate (R2) mapping is an established method for measuring iron overload in various biological tissues. Recently, R2 mapping was used to measure the mean 3D concentration distribution of micron-size particles dispersed in turbulent flows. However, some discrepancy was observed between the measured R2 and the expected decay based on existing theory.