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King, W.

Publications and source records attributed to King, W..

4 recordsLinked to original sources

Metabolomic Network Analysis Reveals Reorganization of Lipid and Steroid Programs Linked to Right Ventricular-Pulmonary Vascular Function in Pulmonary Hypertension

BackgroundPulmonary arterial hypertension (PAH) is characterized by circulating metabolic alterations, but whether these reflect disease-specific metabolic programs or reorganization of normal metabolic architecture, and how they relate to right ventricular-pulmonary vascular function (RV-PV), remains unclear. We hypothesized that the PAH metabolome is organized into biologically coherent, co-regulated metabolic modules whose relationships to RV-PV function would provide insight into known and novel metabolic pathways. MethodsWe applied weighted gene co-expression network analysis (WGCNA) to untargeted metabolomic data from 412 PAH patients enrolled in the multicenter PVDOMICS study. Module preservation analysis was performed in 85 healthy controls, with external replication in an independent single-center pulmonary hypertension cohort of 89 patients. ResultsWGCNA identified 16 distinct metabolic modules organized around biologically coherent programs. A coherent fatty acid axis, spanning substrate pools, {beta}-oxidation intermediates, and conjugated fatty acid disposal products, formed a central organizing structure, with downstream fatty acid oxidation modules strongly associated with adverse hemodynamics and worse RV-pulmonary artery (PA) coupling. Acylcholine-enriched and 5-reduced androgen metabolite modules were associated with favorable hemodynamic indices. Module architecture was largely preserved in healthy controls, with subtle disease-associated modular reorganization, rather than emergence of novel modules, observed in PAH. Core modules were recovered in the replication cohort with conserved hub metabolites. ConclusionsThese findings establish a systems-level framework demonstrating that PAH involves structured intensification and reorganization of interconnected metabolic programs associated with favorable and adverse RV-PV phenotypes. This work provides new insight into the metabolic architecture underlying PAH and identifies coordinated metabolic pathways linked to pulmonary vascular and right ventricular function.

physiology↗

Reproducibility problem with a proposed standard method to measure disinfection efficacy

A collaborative study was carried out in four laboratories to determine the reproducibility of a proposed ASTM International standard method for quantitatively evaluating the efficacy of disinfectants on hard, non-porous surfaces against bacteria. The method, known as the Quantitative Method, has also been suggested as a future regulatory standard for the United States and internationally. The multi-lab study was carried out using Pseudomonas aeruginosa and an alkyl dimethyl benzyl ammonium chloride antimicrobial product diluted in hard water. Results of the study showed acceptable repeatability in log10 reductions within each laboratory, but unacceptable reproducibility across laboratories despite careful analyst training and standardization of test conditions. A follow-up study ruled out analyst-to-analyst differences as the cause of the poor reproducibility. As it currently exists, the Quantitative Method is not sufficiently reproducible. Ruggedness testing to assess the sensitivity of the method to small changes in operational factors is recommended.

microbiology↗

Crowdsourced EEG Experiments: A proof of concept for remote EEG acquisition using EmotivPRO Builder and EmotivLABS

Online research platforms have enabled mass data collection enabling representative samples for cognitive behavioural studies. However, the benefits of online data collection have not been available for cognitive neuroscience fields such as electroencephalography (EEG). In this study, we introduce an approach for remote EEG data collection. We demonstrate how an experiment can be built via the EmotivPRO Builder and deployed to the EmotivLABS website where it can be completed by participants who own EMOTIV EEG headsets. To demonstrate the data collection technique, we collected EEG while participants engaged in a resting state task where participants sat with their eyes open and then eyes closed for two minutes each. We observed a significant difference in alpha power between the two conditions thereby demonstrating the well-known alpha suppression effect. Thus, we demonstrate that EEG data collection, particularly for frequency domain analysis, can be successfully conducted online with remote users.

neuroscience↗

Evaluation of a polymeric composite bone filler scaffold for local antibiotic delivery to prevent Staphylococcus aureus infection in a contaminated bone defect

We previously reported the development of an osteogenic bone filler scaffold consisting of degradable polyurethane (dPU), nano-sized hydroxyapatite (nHA), and decellularized bovine bone particles (DBP). In this report we describe the results of studies aimed at evaluating the use of this scaffold as a means of local antibiotic delivery for the prevention of infection in a segmental bone defect contaminated with Staphylococcus aureus. We evaluated two different scaffold formulations that contained the same components in the same ratios but differed from each other with respect to overall porosity and therefore surface area. Studies done with vancomycin, daptomycin, and gentamicin confirmed that antibiotic uptake was concentration dependent and that increased porosity was correlated with increased uptake and prolonged release of all three antibiotics. Vancomycin could be passively loaded into either scaffold formulation in an amount sufficient to prevent infection, as evidenced by the complete eradication of viable bacteria from the surgical site of most animals in a rabbit model of a contaminated mid-radial segmental bone defect. Even in those few cases in which complete eradication was not achieved, the number of viable bacteria present in the bone was significantly reduced comparison to untreated controls. There was also no radiographic evidence of osteomyelitis in any rabbit treated with vancomycin-loaded scaffold. Microcomputed tomography (CT) of bone defects up to 84 days of exposure to scaffolds with and without vancomycin also demonstrated that the addition of vancomycin even in the highest concentration did not significantly diminish the osteogenic properties of either scaffold formulation. Together, these results demonstrate the potential utility of our bone regeneration scaffold for local antibiotic delivery.

microbiology↗