Objective: Smoking is an important risk factor for cardiovascular disease. Sym pathetic responses to cigarette smoking may be implicated in the link between sm oking and cardiovascular disease. We tested the hypothesi...Objective: Smoking is an important risk factor for cardiovascular disease. Sym pathetic responses to cigarette smoking may be implicated in the link between sm oking and cardiovascular disease. We tested the hypothesis that the sympathetic neural responses to smoking are age dependent. Methods: We examined the effects of cigarette smoking and sham smoking on muscle sympathetic nerve activity, bloo d pressure and heart rate in 14 normotensive middle-aged(49±4 years) and 12 yo ung(29±4 years) habitual smokers matched for body mass index(25±2 kg/m2 in bot h groups). Results: Sham smoking had no significant effect on sympathetic drive, blood pressure or heart rate in either group. Cigarette smoking increased heart rate in both middle-aged subjects and young subjects. In comparison to younger subjects, middle-aged smokers showed similar smoking-related increases in sys tolic blood pressure(SBP)[10±3 versus 12±2 mmHg, respectively, not significant (NS)]. Smoking decreased sympathetic nerve activity by 28±12%of baseline value s(P< 0.01) in young subjects. However, muscle sympathetic nerve activity did not change significantly after smoking in middle-aged subjects(5±8%, NS), despit e the increased blood pressures, which would be expected to inhibit sympathetic activity. By contrast, in young subjects, the heart rate increase(22±2 bpm) was greater than that seen in middle-aged subjects(13±2 bpm, P< 0.01). Conclusion s: The autonomic responses to smoking are age dependent. While blood pressure in creases are similar in both groups, young subjects respond to smoking by marked increases in heart rate and suppression of central sympathetic outflow. In middl e-aged subjects, the heart rate increase is less marked, but sympathetic vasoco nstrictor activity is not suppressed.展开更多
儿童Rolandic癫痫(Rolandic epilepsy,RE),又称儿童良性癫痫伴中央颞区棘波(Benign epilepsy of childhood with centrotemporal spikes,BECTs),是儿童时期最常见的特发性局灶性年龄依赖性癫痫综合征,约占小儿癫痫总体的15%~25%,约为儿...儿童Rolandic癫痫(Rolandic epilepsy,RE),又称儿童良性癫痫伴中央颞区棘波(Benign epilepsy of childhood with centrotemporal spikes,BECTs),是儿童时期最常见的特发性局灶性年龄依赖性癫痫综合征,约占小儿癫痫总体的15%~25%,约为儿童失神癫痫的4倍[1]。RE发作多与睡眠有关,大多只在夜间发作,一般预后良好。然而, RE属从轻型至严重脑功能损害的宽谱系疾病,包括经典型和多种变异型(atypical Rolandic epilepsy,ARE),其中睡眠期癫痫性电持续状态(electrical status epilepticus during slow wave sleep,ESES)、睡眠期持续棘慢波(continuous spike and waves during sleep,CSWS)、Landau Kleffner综合征(Landau Kleffner syndrome,LKS)和Pseudo Lennox综合征(Pseudo Lennox syndrome,PLS)[2]等可致严重认知损害,RE经典型也能引起认知功能受损。因此,国际抗癫痫联盟(ILAE)现已弃用其“良性”称谓[3]。RE病因复杂,对其年龄依赖性发病特征至今缺乏合理解释。主流观点认为,RE由复杂多基因遗传与环境因素相互作用致病,RE及ARE可能是同一遗传机制导致的连续性表型,在癫痫活动的持续时间、位置和扩散区域存在差异[1,4]。RE的临床治疗依然充满艺术性和挑战性。展开更多
文摘Objective: Smoking is an important risk factor for cardiovascular disease. Sym pathetic responses to cigarette smoking may be implicated in the link between sm oking and cardiovascular disease. We tested the hypothesis that the sympathetic neural responses to smoking are age dependent. Methods: We examined the effects of cigarette smoking and sham smoking on muscle sympathetic nerve activity, bloo d pressure and heart rate in 14 normotensive middle-aged(49±4 years) and 12 yo ung(29±4 years) habitual smokers matched for body mass index(25±2 kg/m2 in bot h groups). Results: Sham smoking had no significant effect on sympathetic drive, blood pressure or heart rate in either group. Cigarette smoking increased heart rate in both middle-aged subjects and young subjects. In comparison to younger subjects, middle-aged smokers showed similar smoking-related increases in sys tolic blood pressure(SBP)[10±3 versus 12±2 mmHg, respectively, not significant (NS)]. Smoking decreased sympathetic nerve activity by 28±12%of baseline value s(P< 0.01) in young subjects. However, muscle sympathetic nerve activity did not change significantly after smoking in middle-aged subjects(5±8%, NS), despit e the increased blood pressures, which would be expected to inhibit sympathetic activity. By contrast, in young subjects, the heart rate increase(22±2 bpm) was greater than that seen in middle-aged subjects(13±2 bpm, P< 0.01). Conclusion s: The autonomic responses to smoking are age dependent. While blood pressure in creases are similar in both groups, young subjects respond to smoking by marked increases in heart rate and suppression of central sympathetic outflow. In middl e-aged subjects, the heart rate increase is less marked, but sympathetic vasoco nstrictor activity is not suppressed.
文摘到目前为止各种稳态压力和脉压的前向波、后向(反射)波压力组分对风险预测的研究得出了不同的结论。研究者假设稳态压力[平均动脉压(mean arterial pressure,MAP)]、前向波和反射波各自造成心血管损伤的程度存在器官特异性和年龄依赖性。方法:在来自南非洲裔社区的1384名样本中,确定MAP、前向波或反射波(平面压力波测定仪和SphygmoCor软件)与左心室质量指数(left ventricular mass indexindex,LVMI)(n=997)(超声心动图)、颈动脉内膜中层厚度(intima media thickness,IMT)(n=804)(B超)或主动脉脉搏波传导速度(pulse wave velocity,PWV)(n=1217)之间是否有独立相关性。
文摘儿童Rolandic癫痫(Rolandic epilepsy,RE),又称儿童良性癫痫伴中央颞区棘波(Benign epilepsy of childhood with centrotemporal spikes,BECTs),是儿童时期最常见的特发性局灶性年龄依赖性癫痫综合征,约占小儿癫痫总体的15%~25%,约为儿童失神癫痫的4倍[1]。RE发作多与睡眠有关,大多只在夜间发作,一般预后良好。然而, RE属从轻型至严重脑功能损害的宽谱系疾病,包括经典型和多种变异型(atypical Rolandic epilepsy,ARE),其中睡眠期癫痫性电持续状态(electrical status epilepticus during slow wave sleep,ESES)、睡眠期持续棘慢波(continuous spike and waves during sleep,CSWS)、Landau Kleffner综合征(Landau Kleffner syndrome,LKS)和Pseudo Lennox综合征(Pseudo Lennox syndrome,PLS)[2]等可致严重认知损害,RE经典型也能引起认知功能受损。因此,国际抗癫痫联盟(ILAE)现已弃用其“良性”称谓[3]。RE病因复杂,对其年龄依赖性发病特征至今缺乏合理解释。主流观点认为,RE由复杂多基因遗传与环境因素相互作用致病,RE及ARE可能是同一遗传机制导致的连续性表型,在癫痫活动的持续时间、位置和扩散区域存在差异[1,4]。RE的临床治疗依然充满艺术性和挑战性。
