Effects of intermittent cold-exposure on culprit plaque morphology in ST-segment elevation myocardial infarction patients: a retrospective study based on optical coherence tomography

Objective:Present study aimed to explore the effects of intermittent cold-exposure(ICE)on culprit plaque morphology in patients with ST-segment elevation myocardial infarction(STEMI)in frigid zone.Methods:Totally 848 STEMI patients with plaque rupture(N=637)or plaque erosion(N=211)were enrolled consecutively according to optical coherence tomography imaging.Data on the changes of outdoor air temperature corresponding to 24 solar terms were collected.Patients were divided into different groups according to 24 solar terms and the number of days with indoor central heating.Imaging data were measured and analyzed qualitatively and quantitatively.Statistical analysis was conducted to elucidate the possible association of the STEMI patients of different groups with plaque morphology of culprit vessel with alterations of ambient temperature.Results:The incidence of both plaque rupture and plaque erosion presented trough in summer.The incidence of plaque rupture reached a peak value in early winter when outdoor air temperature dropped below 0℃and declined with supply of central heating.Persistent cold exposure in early winter was positively and significantly associated with plaque rupture.The incidence of plaque erosion presented a peak in severe winter with outdoor air temperature dropping below-20℃and steady supply of central heating.ICE in severe winter was positively and significantly associated with plaque with intact intima,especially in aged male or current smoking patients.The positive correlation of cold exposure with lipid size in culprit plaque in winter weakened with central heating.Conclusion:ICE resulted from switching staying in between outdoor cold environment and indoor warm temperature with central heating in severe winter changed culprit plaque morphology in STEMI.Plaque rupture decreased whereas plaque erosion increased impacted by ICE.The effect of ICE on the transformation of plaque morphology might be explained by reduced lipid deposition.

DEtail-seq is an ultra-efficient and convenient method for meiotic DNA break profiling in multiple organisms

Programmed DNA double-strand break(DSB)formation is a crucial step in meiotic recombination,yet techniques for highefficiency and precise mapping of the 3’ends of DSBs are still in their infancy.Here,we report a novel technique,named DNA End tailing and sequencing(DEtail-seq),which can directly and ultra-efficiently characterize the 3’ends of meiotic DSBs with near single-nucleotide resolution in a variety of species,including yeast,mouse,and human.We find that the 3’ends of meiotic DSBs are stable without significant resection in budding yeast.Meiotic DSBs are strongly enriched in de novo H3K4me3 peaks in the mouse genome at leptotene stage.We also profile meiotic DSBs in human and find DSB hotspots are enriched near the common fragile sites during human meiosis,especially at CCCTC-binding factor(CTCF)-associated enhancers.Therefore,DEtail-seq provides a powerful method to detect DSB ends in various species,and our results provide new insights into the distribution and regulation of meiotic DSB hotspots.