卡马西平对离体蛙心心功能的影响

目的:观察卡马西平对离体蛙心心肌收缩力和心率的影响及其初步机制。方法:根据斯氏蛙心插管方法,蛙心插管内液体恒定体积为1ml,以卡马西平溶液100μl对离体蛙心进行一次加药灌流,使其终浓度为10.58μmol·L^(-1)、21.16μmol·L^(-1)、42.32μmol·L^(-1),采用BL-420生物机能实验系统记录第2分钟内离体蛙心心率、心力峰峰值、心肌平均收缩力的变化;以乙酰胆碱100μl对离体蛙心进行一次加药灌流,使其终浓度为1mg·L^(-1)、以艾司洛尔100μl对离体蛙心进行一次加药灌流,使其终浓度为10 mg·L^(-1)、以乙酰胆碱与卡马西平溶液各50μl同时灌流离体蛙心,使乙酰胆碱和卡马西平终浓度分别为1mg·L^(-1)和21.16μmol·L^(-1)1、以艾司洛尔与卡马西平溶液各50μl同时灌流离体蛙心,使艾司洛尔和卡马西平终浓度分别为10 mg·L^(-1)和21.16μmol·L^(-1),记录第2分钟内离体蛙心心力峰峰值的变化。结果:10.58μmol·L^(-1)、21.16μmol·L^(-1)、42.32μmol·L^(-1)浓度的卡马西平溶液对蛙心心率无影响,但是可以增强离体蛙心心肌自发性收缩的心力峰峰值和平均收缩力(P<0.01),且具有一定浓度依赖性;21.16μmol·L^(-1)卡马西平可明显拮抗乙酰胆碱抑制蛙心心肌收缩峰峰值的作用(P<0.01),同时也可明显拮抗艾司洛尔抑制蛙心心肌收缩峰峰值的作用(P<0.01)。结论:卡马西平可以明显增强心肌收缩力,其机制可能与其兴奋β1受体、阻断M2受体有关。

Effects of Cotrimoxazole Prophylaxis Initiation and Discontinuation on Mortality and Attrition Rates among HIV Patients Who Initiate ART in Southwest China:An Observational Cohort Study

Combination antiretroviral therapy(ART)reduced AIDS-related mortality and increased survival among patients living with HIV by interrupting HIV replication,enhancing immune recovery,and preventing the onset of opportunistic infections[1].In China,ART has rapidly been scaled up since the beginning of the National Free Antiretroviral Treatment Program(NFATP)in 2003[2].By the end of 2016,489,411 individuals diagnosed with HIV were receiving free antiretroviral treatment in China.China is firmly committed to reducing overall AIDS-related mortality and HIV incidence within the country.However,similar to other low-and middle-income countries,the NFATP is challenged by high mortality and attrition shortly after patients initiate ART[3].