examined were condensed nuclear chromatin (A), activated caspase-like molecules (B). Error bars represent standard error of the mean (SEM). Bars with different letters are significantly different. Empty bars represent controls and patterned bars represent treated ookinetes. Found at: doi:10.1371/journal.pone.0012634.s002 (0.19 MB TIF) Figure S3 Nitrite production by NO donors. The production of nitrite by different concentrations of SNOG (A), SNP (B) and SNAP (C) at different time points after dissolving the nitric oxide donors in RPMI-1640 without phenol red, supplemented as outlined in the text (ookinete medium). Measurements were made using the Griess reaction. Error bars represent SEM of 2 replicates. References 1. Ameisen JC (2002) On the origin, evolution, and nature of programmed cell death: a timeline of four billion years. Cell Death Differ 9: 367–393. 2. Ameisen JC (2004) Looking for death at the core of life in the light of evolution. Cell Death Differ 11: 4–10. 3. 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PLoS ONE | www.plosone.org 14 September 2010 | Volume 5 | Issue 9 | e12634