Figure 5.

Identifying responding cells based on calcium peaks: the calcium activity of transfected cells is monitored by fluorescence intensity (Fluo-4), and the resulting ΔF/F₀ traces are analyzed to detect calcium peaks, as shown in (c and d). The presence or absence of calcium transients allows us to separate the recorded cells in each cell culture between “responding” cells (one or more calcium peak) and “nonresponding” cells (no calcium peak detected). For each cell culture, one FOV is recorded with no exposure to the magnet or to the sham magnet, followed by a measurement of another FOV in the same culture during stimulation by a magnet or the sham magnet at a frequency of 0.08 Hz. For each cell culture, the percentage of responding transfected cells during exposure to the magnet or the sham is divided by the percentage of responding cells observed in the control group (no stimulation). These normalized fractions of responding cells are plotted for each cell culture (circles in (a) and (b)). The significance of the increase in calcium activity between the population exposed to a real magnet and the population exposed to a sham magnet is assessed using the left-tailed Wilcoxon test (non-normal distribution). The significance of the difference between the condition is indicated as ^∗p < 0.1; ^∗∗p < 0.05; ^∗∗∗p < 0.01.