Table 1.
Selection of piperaquine resistance in Plasmodium berghei GFP ANKA strain using serial technique. Data are presented as effective doses that reduce parasitaemia by 50% and 90% (ED50, ED90) and as 50% and 90% indexes of resistance (I50 and I90, defined as the ratio of the ED50 or ED90 of the resistant line to that of the parent strain).
| Passage no. | ED50 (mg/kg) | (I50) | ED90 (mg/kg) | (I90) |
|---|---|---|---|---|
| Parent | 1.30 | 1 | 3.52 | 1 |
| 4th | 160.28 | 123.29 | 262.59 | 74.70 |
| (6 months cryopreservation) (5th passage) | 7.50 | 5.77 | 21.90 | 6.22 |
| 9th | 21.40 | 16.46 | 64.50 | 18.32 |
| 17th | 122.00 | 93.85 | 194.00 | 55.11 |
| 27th | 168.08 | 129.29 | 242.38 | 68.86 |
| Drug free passages | ||||
| 5th | 185.27 | 142.52 | 283.71 | 80.60 |
| 10th | 191.46 | 147.28 | 294.98 | 83.80 |
| 27th passage line after 4 months cryopreservation | 110.03 | 84.64 | 223.15 | 63.39 |