FIG. 2.

Alkaline phosphatase (ALP) activity and viability of osteoblasts. Osteoblasts show changes in their viabilities in different stimuli. (A) The viabilities were determined numerically by colorimetric absorbance at a wavelength of 570 nm. (B) Quantitative ALP activity was normalized to cell viability in each sample. Data are expressed as mean ± SD (n = 3). a, versus control without Noggin (−), and b, versus control with Noggin (+). a and *: p < 0.05 was recognized to be significant. (C) A live/dead assay was performed at 24 h after each stimulation. Live/dead cells were detected in green/red fluorescence, respectively. There were no significant differences in the live/dead cell numbers among all conditions.