Center for Pathophysiology, Infectiology and Immunology, Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Vienna, Austria.
Wien Klin Wochenschr. 2010 Oct;122 Suppl 3:66-70. doi: 10.1007/s00508-010-1440-z.
Estimates of the annual number of infections with Plasmodium vivax reach 391 million. So far the blood-schizontocidal therapy with chloroquine remained effective in most parts of the world, but reports about emerging resistance are increasing. The study had the objective of determining the pharmacodynamic interaction between pyronaridine and retinol in Plasmodium vivax, since pyronaridine is a potential alternative for chloroquine and an earlier study had shown strong synergism between pyronaridine and retinol in Plasmodium falciparum. The study was conducted at the Malaria Clinic of Mae Sot, Tak Province, Thailand, near the border to Myanmar. The in vitro observations followed the method of Tasanor. Successful tests were performed with 44 isolates. The mean IC(50), IC(90) and IC(99) values for pyronaridine were 9.8, 2069.6 and 162446.5 nM. The mean IC(50), IC(90) and IC(99) values for the combinations with retinol (corresponding to the 50th, 65th and 80th percentile of the physiological retinol levels in healthy adults) were 1.7, 542.8 and 59379.5 nM for pyronaridine + retinol "low", for the combination with retinol "medium" they were 0.5, 313.7 and 58891.4 nM and for the combination with retinol "high" they were 0.2, 96.7 and 16754.3 nM. These results suggest strong synergism between the two substances.
估计每年感染间日疟原虫的人数达到 3.91 亿。到目前为止，氯喹的血裂殖体杀灭疗法在世界上大多数地区仍然有效，但有关出现耐药性的报告越来越多。本研究的目的是确定吡喹酮和视黄醇在间日疟原虫中的药效学相互作用，因为吡喹酮是氯喹的潜在替代品，早期的研究表明吡喹酮和视黄醇在恶性疟原虫中具有很强的协同作用。该研究在泰国塔可省湄索的疟疾诊所进行，该诊所靠近缅甸边境。体外观察采用 Tasanor 的方法。成功的测试使用了 44 个分离物。吡喹酮的平均 IC50、IC90 和 IC99 值分别为 9.8、2069.6 和 162446.5 nM。吡喹酮与视黄醇（对应于健康成年人生理视黄醇水平的第 50、65 和 80 百分位数）组合的平均 IC50、IC90 和 IC99 值分别为 1.7、542.8 和 59379.5 nM（吡喹酮+视黄醇“低”组合），与视黄醇“中”组合的组合分别为 0.5、313.7 和 58891.4 nM，与视黄醇“高”组合的组合分别为 0.2、96.7 和 16754.3 nM。这些结果表明这两种物质之间存在很强的协同作用。
