Even though the relationship between antiarrhythmic drug usage and subsequent prostate cancer （PCa） risk has recently been highlighted, relevant findings in the previous literature are still inconsistent. In additio...Even though the relationship between antiarrhythmic drug usage and subsequent prostate cancer （PCa） risk has recently been highlighted, relevant findings in the previous literature are still inconsistent. In addition, very few studies have attempted to investigate the association between sodium channel blockers or potassium channel blockers for arrhythmia and the subsequent PCa risk. Therefore, this cohort study aimed to find the relationship between antiarrhythmic drug usage and the subsequent PCa risk using a population-based dataset. The data used in this study were derived from the Longitudinal Health Insurance Database 2005, Taiwan, China. We respectively identified 9988 sodium channel blocker users, 3663 potassium channel blocker users, 65 966 beta-blocker users, 23 366 calcium channel blockers users, and 7031 digoxin users as the study cohorts. The matched comparison cohorts （one comparison subject for each antiarrhythmic drug user） were selected from the same dataset. Each patient was tracked for a 5-year period to define those who were subsequently diagnosed with PCa. After adjusting for sociodemographic characteristics, comorbidities, and age, Cox proportional hazard regressions found that the hazard ratio （HR） of subsequent PCa for sodium channel blocker users was 1.12 （95% confidence interval [CI]： 0.84-1.50）, for potassium channel blocker users was 0.89 （95% CI. 0.59-1.34）, for beta-blocker users was 1.08 （95% Ch 0.96-1.22）, for calcium channel blocker users was 1.14 （95% Ch 0.95-1.36）, and for digoxin users was 0.89 （95% Ch 0.67-1.18）, compared to their matched nonusers. We concluded that there were no statistical associations between different types of antiarrhvthmic drug usage and subsequent PCa risk.展开更多
Background Shensong Yangxin （SSYX） is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current （/Na）, L-type calcium current （/Ca.L）, tr...Background Shensong Yangxin （SSYX） is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current （/Na）, L-type calcium current （/Ca.L）, transient outward potassium current （/to）, delayed rectifier current （/K）, and inward rectifier potassium currents （/K1） in isolated ventricular myocytes. Methods Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. Results SSYX decreased peak Na by （44.84±7.65）% from 27.21±5.35 to 14.88±2..75 pA/pF （n=-5, P〈0.05）. The medicine significantly inhibited the /Ca,L. At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak/Ca,L was reduced by （19.22±1.10）%, （44.82±6.50）% and （50.69±5.64）%, respectively （n=5, all P〈0.05）. SSYX lifted the I-V curve of both /Na and /Ca,L without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of /to by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of /K was decreased by （30.77±1.11）% （n=5, P〈0.05） at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of /K was also inhibited. Similar to the effect on /K, the SSYX inhibited /K1 by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. Conclusions The experiments revealed that SSYX could block multiple ion channels such as /Na /Ca,L, /k, /to and /K1, which may change the action potential duration and contribute to some of its antiarrhythmic effects.展开更多
Background Because of the potential proarrhythmic effect of current antiarrhythmic drugs, it is still desirable to find safer antiarrhythmic drugs worldwide. Paeoniflorin is one of the Chinese herb monomers that have ...Background Because of the potential proarrhythmic effect of current antiarrhythmic drugs, it is still desirable to find safer antiarrhythmic drugs worldwide. Paeoniflorin is one of the Chinese herb monomers that have different effects on many ion channels. The present study aimed to determine the effects of paeoniflorin on cardiac ion channels.Methods Whole-cell patch-clamp technique was used to record ion channel currents. L-type calcium current （/Ca-L）,inward rectifier potassium current （/K1）, and transient outward potassium current （/to1） were studied in rat ventricular myocytes and sodium current （/Na）, slow delayed rectifier current （/Ks）, and HERG current （/Kr） were investigated in transfected human embryonic kidney 293 cells.Results One hundred μmol/L paeoniflorin reduced the peak /ca-L by 40.29% at the test potential of ±10 mV （from （-9.78±0.52） pA/pF to （-5.84±0.89） pA/pF, n=5, P=0.028）. The steady-state activation curve was shifted to more positive potential in the presence of the drug. The half activation potentials were （-11.22±0.27） mV vs. （-5.95±0.84） mV （n=5,P=0.007）, respectively. However, the steady-state inactivation and the time course of recovery from inactivation were not changed. One hundred μmol/L paeoniflorin completely inhibited the peak /Na and the effect was reversible. Moreover,paeoniflorin inhibited the /K1 by 30.13% at the test potential of -100 mV （from （-25.26±8.21） pA/pF to （-17.65±6.52）pA/pF, n=6, F=0.015） without effects on the reversal potential and the rectification property. By contrast, 100 μmol/L paeoniflorin had no effects on/to1, /Ks or /Kr channels.Conclusions The study demonstrated that paeoniflorin blocked /Ca-L, /Na, and /Kf without affecting /to1, /Ks, or /Kr. The multi-channel block effect may account for its antiarrhythmic effects with less proarrhythmic potential.展开更多
Atrial fibrillation （AF） is the most common heart .rhythm disturbance encountered in clinical practice.It affects at least ten million Chinese, constituting a major public health epidemic. For the shortness of resou...Atrial fibrillation （AF） is the most common heart .rhythm disturbance encountered in clinical practice.It affects at least ten million Chinese, constituting a major public health epidemic. For the shortness of resource in the initial stage of new China and the chaos during the culture revolution, there was a scarcity of AF data on the Chinese population. However, Chinese physicians had never stopped exploring in this field, which has provided a solid foundation for today＇s flourishing development in the research of AF. This paper aims to review the major achievements in dealing with AF in the past 60 years in China, especially in the latest 15 years.展开更多
文摘Even though the relationship between antiarrhythmic drug usage and subsequent prostate cancer （PCa） risk has recently been highlighted, relevant findings in the previous literature are still inconsistent. In addition, very few studies have attempted to investigate the association between sodium channel blockers or potassium channel blockers for arrhythmia and the subsequent PCa risk. Therefore, this cohort study aimed to find the relationship between antiarrhythmic drug usage and the subsequent PCa risk using a population-based dataset. The data used in this study were derived from the Longitudinal Health Insurance Database 2005, Taiwan, China. We respectively identified 9988 sodium channel blocker users, 3663 potassium channel blocker users, 65 966 beta-blocker users, 23 366 calcium channel blockers users, and 7031 digoxin users as the study cohorts. The matched comparison cohorts （one comparison subject for each antiarrhythmic drug user） were selected from the same dataset. Each patient was tracked for a 5-year period to define those who were subsequently diagnosed with PCa. After adjusting for sociodemographic characteristics, comorbidities, and age, Cox proportional hazard regressions found that the hazard ratio （HR） of subsequent PCa for sodium channel blocker users was 1.12 （95% confidence interval [CI]： 0.84-1.50）, for potassium channel blocker users was 0.89 （95% CI. 0.59-1.34）, for beta-blocker users was 1.08 （95% Ch 0.96-1.22）, for calcium channel blocker users was 1.14 （95% Ch 0.95-1.36）, and for digoxin users was 0.89 （95% Ch 0.67-1.18）, compared to their matched nonusers. We concluded that there were no statistical associations between different types of antiarrhvthmic drug usage and subsequent PCa risk.
文摘Background Shensong Yangxin （SSYX） is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current （/Na）, L-type calcium current （/Ca.L）, transient outward potassium current （/to）, delayed rectifier current （/K）, and inward rectifier potassium currents （/K1） in isolated ventricular myocytes. Methods Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. Results SSYX decreased peak Na by （44.84±7.65）% from 27.21±5.35 to 14.88±2..75 pA/pF （n=-5, P〈0.05）. The medicine significantly inhibited the /Ca,L. At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak/Ca,L was reduced by （19.22±1.10）%, （44.82±6.50）% and （50.69±5.64）%, respectively （n=5, all P〈0.05）. SSYX lifted the I-V curve of both /Na and /Ca,L without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of /to by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of /K was decreased by （30.77±1.11）% （n=5, P〈0.05） at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of /K was also inhibited. Similar to the effect on /K, the SSYX inhibited /K1 by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. Conclusions The experiments revealed that SSYX could block multiple ion channels such as /Na /Ca,L, /k, /to and /K1, which may change the action potential duration and contribute to some of its antiarrhythmic effects.
文摘Background Because of the potential proarrhythmic effect of current antiarrhythmic drugs, it is still desirable to find safer antiarrhythmic drugs worldwide. Paeoniflorin is one of the Chinese herb monomers that have different effects on many ion channels. The present study aimed to determine the effects of paeoniflorin on cardiac ion channels.Methods Whole-cell patch-clamp technique was used to record ion channel currents. L-type calcium current （/Ca-L）,inward rectifier potassium current （/K1）, and transient outward potassium current （/to1） were studied in rat ventricular myocytes and sodium current （/Na）, slow delayed rectifier current （/Ks）, and HERG current （/Kr） were investigated in transfected human embryonic kidney 293 cells.Results One hundred μmol/L paeoniflorin reduced the peak /ca-L by 40.29% at the test potential of ±10 mV （from （-9.78±0.52） pA/pF to （-5.84±0.89） pA/pF, n=5, P=0.028）. The steady-state activation curve was shifted to more positive potential in the presence of the drug. The half activation potentials were （-11.22±0.27） mV vs. （-5.95±0.84） mV （n=5,P=0.007）, respectively. However, the steady-state inactivation and the time course of recovery from inactivation were not changed. One hundred μmol/L paeoniflorin completely inhibited the peak /Na and the effect was reversible. Moreover,paeoniflorin inhibited the /K1 by 30.13% at the test potential of -100 mV （from （-25.26±8.21） pA/pF to （-17.65±6.52）pA/pF, n=6, F=0.015） without effects on the reversal potential and the rectification property. By contrast, 100 μmol/L paeoniflorin had no effects on/to1, /Ks or /Kr channels.Conclusions The study demonstrated that paeoniflorin blocked /Ca-L, /Na, and /Kf without affecting /to1, /Ks, or /Kr. The multi-channel block effect may account for its antiarrhythmic effects with less proarrhythmic potential.
文摘Atrial fibrillation （AF） is the most common heart .rhythm disturbance encountered in clinical practice.It affects at least ten million Chinese, constituting a major public health epidemic. For the shortness of resource in the initial stage of new China and the chaos during the culture revolution, there was a scarcity of AF data on the Chinese population. However, Chinese physicians had never stopped exploring in this field, which has provided a solid foundation for today＇s flourishing development in the research of AF. This paper aims to review the major achievements in dealing with AF in the past 60 years in China, especially in the latest 15 years.
