AIM To determine the optimum resting tension(ORT) for in vitro human pulmonary artery(PA) ring preparations.METHODS Pulmonary arteries were dissected from disease free sections of the resected lung in the operating th...AIM To determine the optimum resting tension(ORT) for in vitro human pulmonary artery(PA) ring preparations.METHODS Pulmonary arteries were dissected from disease free sections of the resected lung in the operating theatre and tissue samples were directly sent to the laboratory in Krebs-Henseleit solution(Krebs).The pulmonary arteries were then cut into 2 mm long rings.PA rings were mounted in 25 m L organ baths or 8 m L myograph chambers containing Krebs compound(37 ℃,bubbled with 21% O_2:5% CO_2) to measure changes in isometric tension.The resting tension was set at 1-gram force(gf) with vessels being left static to equilibrate for duration of one hour.Baseline contractile reactions to 40 mmol/L KCl were obtained from a resting tension of 1 gf.Contractile reactions to 40 mmol/L KCl were then obtained from stepwise increases in resting tension(1.2,1.4,1.6,1.8 and 2.0 gf).RESULTS Twenty PA rings of internal diameter between 2-4 mmwere prepared from 4 patients.In human PA rings incrementing the tension during rest stance by 0.6 gf,up to 1.6 gf significantly augmented the 40 mmol/L KCl stimulated tension.Further enhancement of active tension by 0.4 gf,up to 2.0 gf mitigate the 40 mmol/L KCl stimulated reaction.Both Myograph and the organ bath demonstrated identical conclusions,supporting that the radial optimal resting tension for human PA ring was 1.61 g.CONCLUSION The radial optimal resting tension in our experiment is 1.61 gf(15.78 m N) for human PA rings.展开更多
目的探讨中国北方非糖尿病人群中静息心率与新发高血压(NOH)的关系。方法采用前瞻性队列研究方法,以参加2006-2007年度开滦集团职工健康体检的职工101 510人中收缩压<140 mm Hg(1 mm Hg=0.133kPa)和舒张压<90mm Hg、无高血压病史...目的探讨中国北方非糖尿病人群中静息心率与新发高血压(NOH)的关系。方法采用前瞻性队列研究方法,以参加2006-2007年度开滦集团职工健康体检的职工101 510人中收缩压<140 mm Hg(1 mm Hg=0.133kPa)和舒张压<90mm Hg、无高血压病史、未使用降压药物且血压测量资料完整及空腹血糖<7.0mmol/L、无糖尿病病史、未使用降糖药物及静息心率测量资料完整的职工49 290人作为观察队列。排除未参加2008-2009或2010-2011年度体检以及血压资料缺失者,最终纳入统计分析29 680人。依据2006-2007年度静息心率测量值将观察对象分为静息心率<67、67~<71、71~<78、≥78次/min共4组,采用多因素Cox风险回归模型分析静息心率与NOH的关系。结果入选者平均随访(3.5±0.9)年。静息心率<67、67~<71、71~<78、≥78次/min组高血压的发病密度分别为102.2、107.2、112.1、120.3/1000人年。4组男性和女性高血压发病密度分别为116.3、124.5、132.5、139.4/1000人年和60.5、63.6、65.1、68.9/1000人年。影响NOH的多因素Cox回归模型分析显示,校正了年龄、性别、收缩压、舒张压、体质量指数、空腹血糖、三酰甘油、总胆固醇、高敏C反应蛋白、高密度脂蛋白胆固醇、吸烟、饮酒、高血压家族史后,与静息心率<67次/min组比较,67~<71、71~<78、≥78次/min组NOH发病风险增加,HR值(95%CI)分别为1.07(1.01~1.13)、1.08(1.02~1.14)、1.15(1.09~1.22)。在不同性别人群校正上述因素后,心率对女性NOH的影响不再有统计学意义,但仍增加男性NOH的发病风险。结论静息心率加快者未来发生高血压的风险增加,在男性中更加显著。展开更多
文摘AIM To determine the optimum resting tension(ORT) for in vitro human pulmonary artery(PA) ring preparations.METHODS Pulmonary arteries were dissected from disease free sections of the resected lung in the operating theatre and tissue samples were directly sent to the laboratory in Krebs-Henseleit solution(Krebs).The pulmonary arteries were then cut into 2 mm long rings.PA rings were mounted in 25 m L organ baths or 8 m L myograph chambers containing Krebs compound(37 ℃,bubbled with 21% O_2:5% CO_2) to measure changes in isometric tension.The resting tension was set at 1-gram force(gf) with vessels being left static to equilibrate for duration of one hour.Baseline contractile reactions to 40 mmol/L KCl were obtained from a resting tension of 1 gf.Contractile reactions to 40 mmol/L KCl were then obtained from stepwise increases in resting tension(1.2,1.4,1.6,1.8 and 2.0 gf).RESULTS Twenty PA rings of internal diameter between 2-4 mmwere prepared from 4 patients.In human PA rings incrementing the tension during rest stance by 0.6 gf,up to 1.6 gf significantly augmented the 40 mmol/L KCl stimulated tension.Further enhancement of active tension by 0.4 gf,up to 2.0 gf mitigate the 40 mmol/L KCl stimulated reaction.Both Myograph and the organ bath demonstrated identical conclusions,supporting that the radial optimal resting tension for human PA ring was 1.61 g.CONCLUSION The radial optimal resting tension in our experiment is 1.61 gf(15.78 m N) for human PA rings.
文摘目的探讨中国北方非糖尿病人群中静息心率与新发高血压(NOH)的关系。方法采用前瞻性队列研究方法,以参加2006-2007年度开滦集团职工健康体检的职工101 510人中收缩压<140 mm Hg(1 mm Hg=0.133kPa)和舒张压<90mm Hg、无高血压病史、未使用降压药物且血压测量资料完整及空腹血糖<7.0mmol/L、无糖尿病病史、未使用降糖药物及静息心率测量资料完整的职工49 290人作为观察队列。排除未参加2008-2009或2010-2011年度体检以及血压资料缺失者,最终纳入统计分析29 680人。依据2006-2007年度静息心率测量值将观察对象分为静息心率<67、67~<71、71~<78、≥78次/min共4组,采用多因素Cox风险回归模型分析静息心率与NOH的关系。结果入选者平均随访(3.5±0.9)年。静息心率<67、67~<71、71~<78、≥78次/min组高血压的发病密度分别为102.2、107.2、112.1、120.3/1000人年。4组男性和女性高血压发病密度分别为116.3、124.5、132.5、139.4/1000人年和60.5、63.6、65.1、68.9/1000人年。影响NOH的多因素Cox回归模型分析显示,校正了年龄、性别、收缩压、舒张压、体质量指数、空腹血糖、三酰甘油、总胆固醇、高敏C反应蛋白、高密度脂蛋白胆固醇、吸烟、饮酒、高血压家族史后,与静息心率<67次/min组比较,67~<71、71~<78、≥78次/min组NOH发病风险增加,HR值(95%CI)分别为1.07(1.01~1.13)、1.08(1.02~1.14)、1.15(1.09~1.22)。在不同性别人群校正上述因素后,心率对女性NOH的影响不再有统计学意义,但仍增加男性NOH的发病风险。结论静息心率加快者未来发生高血压的风险增加,在男性中更加显著。
