Background: The rotation and twist of the left ventricle (LV) have been comprehensively evaluated at rest. However, little is known about rotational mechanics during dobutamine stress echocardiography (DSE).
Aims: We aimed to quantify and compare the basal and apical rotation and twist of the LV at rest as well as at the peak and recovery stages of DSE in patients with and without coronary artery disease (CAD).
Methods: We enrolled 91 patients, including 48 patients with CAD and 43 patients without CAD (mean [SD] age, 62 [9] years and 61 [10] years, respectively). Coronary artery disease was defined as the presence of stenoses of 50% or more in the left main coronary artery and/or stenoses of 70% or more in other epicardial arteries. Rotation was measured by 2‑dimensional speckle‑tracking echocardiography, and twist was calculated as the difference between the basal and apical rotation.
Results: Neither rotation nor twist differed between patients with and without CAD at rest, although apical rotation was significantly greater in the CAD group at peak DSE (mean [SD], 5.43° [3.45°] vs 3.71° [3.52°], P = 0.01) and at recovery (mean [SD], 5.05° [3.65°] vs 2.87° [2.73°], P <0.01). On the contrary, the absolute value for basal rotation at recovery was higher in patients without CAD (mean [SD], 3.87° [3.37°] vs 2.63° [2.43°], P = 0.03). In both groups, the rotation and twist did not change significantly during the dobutamine challenge.
Conclusions: During DSE, we observed differences in LV rotation between patients with and without CAD, revealing the effect of ischemia on deformation parameters.
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http://dx.doi.org/10.33963/KP.14870 | DOI Listing |
Nat Commun
January 2025
School of Material Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, People's Republic of China.
Interlayer coupling in 2D heterostructures can result in a reduction of the rotation symmetry and the generation of quantum phenomena. Although these effects have been demonstrated in transition metal dichalcogenides (TMDs) with mismatched interfaces, the role of band hybridization remains unclear. In addition, the creation of flat bands at the valence band maximum (VBM) of TMDs is still an open challenge.
View Article and Find Full Text PDFAcc Chem Res
January 2025
Department of Chemistry, University of California, Berkeley, California 94720, United States.
ConspectusThe electronic properties of atomically thin van der Waals (vdW) materials can be precisely manipulated by vertically stacking them with a controlled offset (for example, a rotational offset─i.e., twist─between the layers, or a small difference in lattice constant) to generate moiré superlattices.
View Article and Find Full Text PDFNature
January 2025
Department of Chemistry, University of Manchester, Manchester, UK.
Cells display a range of mechanical activities generated by motor proteins powered through catalysis. This raises the fundamental question of how the acceleration of a chemical reaction can enable the energy released from that reaction to be transduced (and, consequently, work to be done) by a molecular catalyst. Here we demonstrate the molecular-level transduction of chemical energy to mechanical force in the form of the powered contraction and powered re-expansion of a cross-linked polymer gel driven by the directional rotation of artificial catalysis-driven molecular motors.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia.
Understanding how structural modifications affect the photophysics of organic linkers is crucial for their integration into metal-organic frameworks (MOFs) for light-driven applications. This study explores the impact of varying the amine functional group position on two terephthalic acid derivatives─linker and linker ─by investigating their photophysics through a combination of steady-state and ultrafast laser spectroscopy and time-dependent density functional theory (TD-DFT) calculations. With tetrahydrofuran as the solvent, time-correlated single-photon counting revealed a 2-fold increase in the S excited-state lifetime of the molecule with the amine group at the meta position compared with that of the molecule with the amine group at the ortho position.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
College of Materials and Textile Engineering, Jiaxing University, Jiaxing 314001, China.
Programmable organization of uniform organic/inorganic functional building blocks into large-scale ordered superlattices has attracted considerable attention since the bottom-up self-organization strategy opens up a robust and universal route for designing novel and multifunctional materials with advanced applications in memory storage devices, catalysis, photonic crystals, and biotherapy. Despite making great efforts in the construction of superlattice materials, there still remains a challenge in the preparation of organic/inorganic hybrid superlattices with tunable dimensions and exotic configurations. Here, we report the spontaneous self-organization of polystyrene-tethered gold nanoparticles (AuNPs@PS) into freestanding organic/inorganic hybrid superlattices templated at the diethylene glycol-air interface.
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