Tracking circadian rhythms of bone mineral deposition in murine calvarial organ cultures

Osteoblasts, which orchestrate the deposition of small apatite crystals through the expression of nucleating proteins, have been shown to also express clock genes associated with the circadian signaling pathway. We hypothesized that protein‐mediated bone mineralization may be linked to circadian oscillator mechanisms functioning in peripheral bone tissue. In this study, Per1 expression in ex vivo neonatal murine calvaria organ cultures was monitored for 6 days using a Per1 ‐ luciferase transgene as a bioluminescent indicator of clock function. Fluctuations in Per1 expression had a period of 25 ± 4 hours ( n  = 14) with early expression at CT09:59 ± 03:37 (CT = circadian time). We also established the kinetics of mineral deposition in developing bone by using noninvasive Raman microscopy to track mineral accumulation in calvarial tissue. The content and quality of newly deposited mineral was continually examined at the interparietal bone/fontanel boundary for a period of 6 days with 1‐hour temporal resolution. Using this approach, mineralization over time exhibited bursts of mineral deposition followed by little or no deposition, which was recurrent with a periodicity of 26.8 ± 9.6 hours. As many as six near‐daily mineralization events were observed in the calvaria before deposition ceased. Earliest mineralization events occurred at CT16:51 ± 03:45, which is 6 hours behind Per1 expression. These findings are consistent with the hypothesis that mineralization in developing bone tissue is regulated by a local circadian oscillator mechanism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99084/1/jbmr1924.pd

Acute safety, effectiveness, and real-world clinical usage of ultra-high density mapping for ablation of cardiac arrhythmias: results of the TRUE HD study

AIMS: The objective of this study was to verify acute safety, performance, and usage of a novel ultra-high density mapping system in patients undergoing ablation procedure in a real-world clinical setting. METHODS AND RESULTS: The TRUE HD study enrolled patients undergoing catheter ablation with mapping for all arrhythmias (excluding de novo atrial fibrillation) who were followed for 1 month. Safety was determined by collecting all serious adverse events and adverse events associated with the study devices. Performance was determined as the composite of: ability to map the arrhythmia/substrate, complete the ablation applications, arrhythmia termination (where applicable), and ablation validation. Use of mapping system in the ablation validation workflow was also evaluated. Among the 519 patients who underwent a complete (504) or attempted (15) procedure, 21 (4%) serious ablation-related complications were collected, with 3 (0.57%) potentially related to the mapping catheter. Four hundred and twenty treated patients resulted in a successful procedure confirmed by arrhythmia-specific validation techniques (83.3%; 95% confidence interval: 79.8-86.5%). A total of 1419 electroanatomical maps were created with a median acquisition time of 9:23 min per map. Of these, 372 maps in 222 (44%) patients were collected for ablation validation purposes. Following validation mapping, 162/222 (73%) patients required additional ablation. CONCLUSION: In the TRUE HD study mapping was associated with rates of acute success and complications consistent with previously published reports. Importantly, a low percentage of events (0.57%) was attributed to the mapping catheter. When performed, validation mapping was useful for identifying additional targets for ablation in the majority of patients

2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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withdrawn 2017 hrs ehra ecas aphrs solaece expert consensus statement on catheter and surgical ablation of atrial fibrillation

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Electronic monitoring in fisheries: Lessons from global experiences and future opportunities

Since the beginning of the 21st century, electronic monitoring (EM) has emerged as a cost‐efficient supplement to existing catch monitoring programmes in fisheries. An EM system consists of various activity sensors and cameras positioned on vessels to remotely record fishing activity and catches. The first objective of this review was to describe the state of play of EM in fisheries worldwide and to present the insights gained on this technology based on 100 EM trials and 12 fully implemented programmes. Despite its advantages, and its global use for monitoring, progresses in implementation in some important fishing regions are slow. Within this context, the second objective was to discuss more specifically the European experiences gained through 16 trials. Findings show that the three major benefits of EM were as follows: (a) cost‐efficiency, (b) the potential to provide more representative coverage of the fleet than any observer programme and (c) the enhanced registration of fishing activity and location. Electronic monitoring can incentivize better compliance and discard reduction, but the fishing managers and industry are often reluctant to its uptake. Improved understanding of the fisher's concerns, for example intrusion of privacy, liability and costs, and better exploration of EM benefits, for example increased traceability, sustainability claims and market access, may enhance implementation on a larger scale. In conclusion, EM as a monitoring tool embodies various solid strengths that are not diminished by its weaknesses. Electronic monitoring has the opportunity to be a powerful tool in the future monitoring of fisheries, particularly when integrated within existing monitoring programmes