Background: Time- and frequency-domain estimates of activation rate have been proposed to guide atrial fibrillation (AF) ablation in patients, but their electrophysiological correlates are unclear.
Objective: This study sought to examine the relative correlation of average electrical cycle length (CL) and dominant frequency (DF) during AF with reference optical mapping measures.
Methods: Eight sheep hearts were Langendorff-perfused and superfused with oxygenated Tyrode solution inside a tank representing the human thorax. Optical mapping (DI-4-ANEPPS) of 4 × 4 cm2 in the left atrium was performed at 0.5 mm/pixel and 600 fps. A 20-pole catheter was placed in the optical field of view to acquire 1.2-kHz unipolar recordings by the EnSite NavX System (ENS; St. Jude Medical, St. Paul, MN) optimized for CL and DF calculation. During AF, 5-second-long simultaneous optical and electrical signals were analyzed for CL and DF.
Results: During pacing, DF measurements had fewer false results than CL (6.6% to 2.5% vs. 21.5% to 4.4% depending on filtering, P <.001). During AF in regions showing periodic waves on both sides of the catheter optical 1,000/CL versus DF correlation showed 95% confidence identity and was better than unipolar measurements in the ENS (adjusted R(2): 0.58879 vs. 0.12902; P < 10(-6)). DFs of unipolar signals correlated better than CLs with DFs of optical signals. Similarly, bipolar DF correlation with optical DF was not different from identity (P >.157), but the bipolar CL showed smaller identity with the optical CL (P <.0004).
Conclusion: DF values of unipolar and bipolar signals correlate with those of optical signals better than CL values for the respective signals.
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http://dx.doi.org/10.1016/j.hrthm.2011.05.007 | DOI Listing |
Struct Dyn
January 2025
Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
Sub-ångström spatial resolution of electron density coupled with sub-femtosecond to few-femtosecond temporal resolution is required to directly observe the dynamics of the electronic structure of a molecule after photoinitiation or some other ultrafast perturbation, such as by soft X-rays. Meeting this challenge, pushing the field of quantum crystallography to attosecond timescales, would bring insights into how the electronic and nuclear degrees of freedom couple, enable the study of quantum coherences involved in molecular dynamics, and ultimately enable these dynamics to be controlled. Here, we propose to reach this realm by employing convergent-beam x-ray crystallography with high-power attosecond pulses from a hard-x-ray free-electron laser.
View Article and Find Full Text PDFBMC Musculoskelet Disord
January 2025
Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital, College of Clinical Medicine for Obstetrics and Gynecology and Pediatrics, Fujian Medical University, 18 Daoshan Road, Fuzhou, 350001, China.
Background: Congenital muscular dystrophies (CMDs) and myopathies (CMYOs) are a clinically and genetically heterogeneous group of neuromuscular disorders that share common features, such as muscle weakness, hypotonia, characteristic changes on muscle biopsy and motor retardation. In this study, we recruited eleven families with early-onset neuromuscular disorders in China, aimed to clarify the underlying genetic etiology.
Methods: Essential clinical tests, such as biomedical examination, electromyography and muscle biopsy, were applied to evaluate patient phenotypes.
Comput Methods Programs Biomed
January 2025
College of Medical Instruments, Shanghai University of Medicine and Health Sciences, Shanghai, 201318, PR China; Shanghai Yangpu Mental Health Center, Shanghai, 200093, PR China. Electronic address:
Background And Objective: The hybrid brain computer interfaces (BCI) combining electroencephalogram (EEG) and functional near-infrared spectroscopy (fNIRS) have attracted extensive attention for overcoming the decoding limitations of the single-modality BCI. With the deepening application of deep learning approaches in BCI systems, its significant performance improvement has become apparent. However, the scarcity of brain signal data limits the performance of deep learning models.
View Article and Find Full Text PDFDNA Repair (Amst)
January 2025
School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel; Edmond J. Safra Center for Bioinformatics, Tel Aviv University, Tel Aviv 6997801, Israel; Department of Biomedical Engineering, Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv 6997801, Israel. Electronic address:
Quantitative genomic mapping of DNA damage may provide insights into the underlying mechanisms of damage and repair. Sequencing based approaches are bound to the limitations of PCR amplification bias and read length which hamper both the accurate quantitation of damage events and the ability to map them to structurally complex genomic regions. Optical Genome mapping in arrays of parallel nanochannels allows physical extension and genetic profiling of millions of long genomic DNA fragments, and has matured to clinical utility for characterization of complex structural aberrations in cancer genomes.
View Article and Find Full Text PDFElife
January 2025
Center for Spatial and Functional Genomics, The Children's Hospital of Philadelphia, Philadelphia, United States.
The prevalence of childhood obesity is increasing worldwide, along with the associated common comorbidities of type 2 diabetes and cardiovascular disease in later life. Motivated by evidence for a strong genetic component, our prior genome-wide association study (GWAS) efforts for childhood obesity revealed 19 independent signals for the trait; however, the mechanism of action of these loci remains to be elucidated. To molecularly characterize these childhood obesity loci, we sought to determine the underlying causal variants and the corresponding effector genes within diverse cellular contexts.
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