Exercise regulates cardiac metabolism: Sex does matter

Cardiac substrate utilization remains a critical focus for the research community.1 Research has acknowledged the role of metabolic flexibility in the development and progression of cardiac dysfunction during a variety of diseases and conditions.2,3 Under resting basal conditions,the heart relies on fatty acid metabolism as the primary energy source with glucose,lactate,ketone bodies,pyruvate,acetate,and branched-chain amino acids contributing as substrates depending on substrate availability,hormonal status,and myocardial conditioning.4 In addition to pathological states,physiological states,such as acute exercise,induce dynamic changes in substrate metabolism,including nearly a 10-fold increase in myocardial oxygen consumption.3,5 To meet the increased demand for energy during and after a bout of exercise,the heart muscle must exhibit metabolic flexibility and selectively utilize different substrates for adenosine triphosphate production.Moreover,metabolic substrate adaptations depend on the frequency,intensity,duration,and mode of exercise while multiple metabolic fluxes,such as the use,storage and mobilization of substrates must be coordinated to maintain energy homeostasis.1,2 Although many different processes of exercise-induced regulation and metabolic remodeling have been identified,35 the effect of exercise on cellular metabolism and the landscape of metabolic pathway regulation in response to both acute exercise and chronic exercise training remain unclear.

超声检查对肠系膜上动脉综合征的诊断价值

目的筛选常规超声、口服胃窗造影剂超声及两者联合对肠系膜上动脉综合征(SMAS)的诊断标准并比较其诊断价值。方法连续性纳入2020年2月至2022年2月因不明原因腹痛、腹胀、恶心、呕吐、反胃、体质量下降等原因来中山大学附属第六医院就诊,临床疑诊SMAS行超声检查的患者51例。常规超声记录腹主动脉与肠系膜上动脉之间夹角(AMA)、腹主动脉与肠系膜上动脉之间距离(AMD)。口服胃窗造影剂超声记录腹主动脉与肠系膜上动脉夹角内十二指肠内径(D1)、夹角前十二指肠内径(D2)及D2/D1。回顾性分析所有超声检查资料,以对比增强计算机断层扫描(CECT)及上消化道钡餐作为诊断金标准,应用受试者工作特征(ROC)曲线分析并获得常规超声及口服胃窗造影剂超声的诊断指标,比较常规超声、口服胃窗造影剂超声及两者联合诊断SMAS的诊断价值。结果根据ROC曲线筛查出常规超声诊断SMAS的指标为:AMA≤16°[曲线下面积(AUC)=0.806]、AMD≤3.3 mm(AUC=0.685);口服胃窗造影剂超声诊断SMAS的指标为:D1≤5.5 mm(AUC=0.849)、D2≥19 mm(AUC=0.725)、D2/D1≥2.9(AUC=0.884)。常规超声、口服胃窗造影剂超声及两者联合分别以AMA≤16°或AMD≤3.3 mm、D2/D1≥2.9及AMA≤16°或AMD≤3.3 mm且D2/D1≥2.9为诊断标准,三者诊断SMAS的敏感度分别为95.2%、85.7%和85.7%,特异度分别为53.3%、83.3%和93.3%,准确性分别为70.6%、84.3%和90.2%,AUC分别为0.743、0.845和0.895。结论常规超声联合口服胃窗造影剂超声可作为临床诊断SMAS的有效方案。