Confocal fluorescence microscopic images of HeLa cells, with or without pretreatment with H2O2 (50 μM) for 2 h, stained with (a) Peroxymycin-1 or puromycin (1 μM) or (b) Ctrl-Peroxymycin-1 (1 μM) for 4 h. The cells were then subsequently washed, fixed, stained, and imaged. All images were recorded by use of the same imaging parameters with the Alexa488 channel. (c) Cellular fluorescence intensities of HeLa cells as determined by ImageJ. Error bars denote SD (n = 5). **p < 0.01.