Case Report and Genomic Analysis of Cefiderocol-Resistant Escherichia coli Clinical Isolates

ObjectivesCefiderocol is a novel siderophore cephalosporin with in vitro activity against multidrug-resistant (MDR), gram-negative bacteria and intrinsic structural stability to all classes of carbapenemases. We sought to identify gene variants that could affect the mechanism of action (MOA) of cefiderocol.MethodsWe report a case of bacteremia in a liver transplant candidate with a strain of carbapenem-resistant Escherichia coli that was found to be resistant to cefiderocol despite no prior treatment with this antimicrobial agent. Using whole-genome sequencing, we characterized the genomic content of this E coli isolate and assessed for genetic variants between related strains that were found to be cefiderocol susceptible.ResultsWe identified several variants in genes with the potential to affect the mechanism of action of cefiderocol.ConclusionsThe cefiderocol resistance in the E coli isolate identified in this study is likely due to mutations in the cirA gene, an iron transporter gene

Physiological assessment of ventricular myocardial voltage using omnipolar electrograms

Background Characterization of myocardial health by bipolar electrograms are critical for ventricular tachycardia therapy. Dependence of bipolar electrograms on electrode orientation may reduce reliability of voltage assessment along the plane of arrhythmic myocardial substrate. Hence, we sought to evaluate voltage assessment from orientation‐independent omnipolar electrograms. Methods and Results We mapped the ventricular epicardium of 5 isolated hearts from each species—healthy rabbits, healthy pigs, and diseased humans—under paced conditions. We derived bipolar electrograms and voltage peak‐to‐peak (Vpps) along 2 bipolar electrode orientations (horizontal and vertical). We derived omnipolar electrograms and Vpps using omnipolar electrogram methodology. Voltage maps were created for both bipoles and omnipole. Electrode orientation affects the bipolar voltage map with an average absolute difference between horizontal and vertical of 0.25±0.18 mV in humans. Vpps provide larger absolute values than horizontal and vertical bipolar Vpps by 1.6 and 1.4 mV, respectively, in humans. Bipolar electrograms with the largest Vpps from either along horizontal or vertical orientation are highly correlated with omnipolar electrograms and with Vpps values (0.97±0.08 and 0.94±0.08, respectively). Vpps values are more consistent than bipoles, in both beat‐by‐beat (CoV, 0.28±0.19 versus 0.08±0.13 in human hearts) and rhythm changes (0.55±0.21 versus 0.40±0.20 in porcine hearts). Conclusions Omnipoles provide physiologically relevant and consistent voltages that are along the maximal bipolar direction on the plane of the myocardium

Enhanced Nonenzymatic Glucose-Sensing Properties of Electrodeposited NiCo₂O₄–Pd Nanosheets: Experimental and DFT Investigations

Here, we report the facile synthesis of NiCo₂O₄ (NCO) and NiCo₂O₄–Pd (NCO–Pd) nanosheets by the electrodeposition method. We observed enhanced glucose-sensing performance of NCO–Pd nanosheets as compared to bare NCO nanosheets. The sensitivity of the pure NCO nanosheets is 27.5 μA μM^–1 cm^–2, whereas NCO–Pd nanosheets exhibit sensitivity of 40.03 μA μM^–1 cm^–2. Density functional theory simulations have been performed to qualitatively support our experimental observations by investigating the interactions and charge-transfer mechanism of glucose on NiCo₂O₄ and Pd-doped NiCo₂O₄ through demonstration of partial density of states and charge density distributions. The presence of occupied and unoccupied density of states near the Fermi level implies that both Ni and Co ions in NiCo₂O₄ can act as communicating media to transfer the charge from glucose by participating in the redox reactions. The higher binding energy of glucose and more charge transfer from glucose to Pd-doped NiCo₂O₄ compared with bare NiCo₂O₄ infer that Pd-doped NiCo₂O₄ possesses superior charge-transfer kinetics, which supports the higher glucose-sensing performance

MEA: an energy efficient algorithm for dense sector-based wireless sensor networks

In this article, first the energy efficiency of sector-shaped wireless sensor networks is analytically investigated. Based on this study, it is shown that the efficiency of existing data propagation algorithms which consider equal ring width is not optimal and may be improved further. Then, we introduce an energy efficient algorithm for these networks which is called minimum energy algorithm (MEA). The detailed analysis verifies that the proposed algorithm has the minimum energy consumption. Although the main emphasis of the proposed technique is on minimizing the energy, it somehow balances the energy consumption in the sector-shaped network as well. In addition, it is shown that the proposed idea can be applied to all existing energy balancing algorithms. The efficacy of the proposed algorithm is studied for networks with different sizes and node densities. The results show that, for example, for a network with a radius of 440 m and four rings when the MEA algorithm is combined with an efficient full power control algorithm (based on equal ring width), the energy conservation increases 50% more. Finally, the results show that the energy conservation of the proposed algorithm increases with the network size.Peer reviewe