Résumé
Objective To study the antimalarial activity of naphthoquine phosphate combined with artemisinine against Plasmodium knowlesi in rhesus monkey.Methods Monkeys were randomly divided into 9 groups(3/group).The monkeys in groups A and B were treated i.g.once daily for 3 days with 6 or 10 mg/kg of naphthoquine phosphate respectively.Those in groups C and D were treated i.g.twice for the 1st day and once for the 2nd and 3rd day with 31.6 or 100 mg/kg of artemisinine respectively.In groups E, F and G, they were treated i.g.only once with the combination of naphthoquine phosphate 10 mg/kg and artemisinine 10, 20 or 25 mg/kg respectively.Groups H and I served as controls which were treated i.g.only once with 10 mg/kg of naphthoquine phosphate and 30 mg/kg of artemisinine respectively.Parasitemia was examined beginning 24 h after drug administration.The observation lasted 105 days when no more parasite was found.Results At 24 h after drug administration, the parasite reduction rate in all groups was higher than 90%.The parasite clearance time for groups E, F and G was(56.0?16.0),(53.3?4.6), and(56.0?8.0) h respectively, more rapid than that of Group H(69.3?4.6) h.There were 1, 3, 3, 2, 2, and 3 monkeys in groups A, B, D, E, F, and G respectively which were cured.No monkeys were cured in groups C, H and I.Conclusion The combination of naphthoquine phosphate and artemisinine is superior to the single component and the optimum proportion in the combination is 1:2.5 in treating P.knowlesi infection in monkeys.
Résumé
Objective To understand whether or not artesunate (Art. ) combined with naphtho-quine (Nap. ) can delay the resistance of Plasmodium falciparum to Art. Methods In Group A, P. falciparum was cultured in culture medium and was stimulated by Art/Nap disconnectedly, and in Group B, stimulated by Art disconnectedly. When P. falciparum recovered to normal growth level, the changes of sensitivity (ID50) to the drugs were compared between the two groups after P. falciparum touched on the drug. Results In Group A, the times P. falciparum recovered to normal growth level were 24, 37 d respectively when it contacted the drugs in the first and second times; P. falciparum didn't recover to normal growth level in 90 d when it contacted the drugs in the third time. In Group B, the times P. falciparum recovered to normal growth level were 16. 7 d (15-20) on average. ID50(s) of Art/Nap were 2.42/37.81, 1. 70/26.30 nmol/L before and 65 d after contacting the drugs in Group A; ID50(s) of Art were 9. 60, 30. 61, 85.12 nmol/L before and 68 and 129 d after contacting the drug in Group B. Conclusion Artesunate-resistant P. falciparum can be cultured by touching artesunate at intervals in vitro; Artesunate combined with naph-thoquine may delay the resistance of P. falciparum to artesunate in vitro.
Résumé
Objective To compare the efficacy and safety of naphthoquine, artemisinine and a combination of the two drugs in the treatment of faciparum malaria. Methods Of 230 patients, 100 patients were treated with combined regime (Co-NQ), 100 patients were treated with naphthoquine (NQ) and 30 patients were treated with artemisinine (QHS). All patients were hospitalized for 7 days and followed up for 28 days. Results The mean fever clearance time for Co-NQ, NQ, and QHS was (17.5 ?12.3)h, (32.7?17.7)h and (18.1?9.7)h respectively; the mean parasite clearance time was (30.0?8. 8)h,(45.5?10.0)h and (29.1?6.0)h respectively; and the 28 days cure rate was 97.0% ,100.0% and 66.7% respectively. Conclusion The Co-NQ possesses benefits of both naphthoquine and artemisinine, acting rapidly, with a short course of only one dose and a high cure rate. The regime is well tolerated by patients.