Densitometric estimates of periapical status were obtained from digitized radiographs as the ratio of mean gray value of an area of radiolucency (AR) to an adjacent and similar-sized normal (N) area (AR/N).
On the basis of 3-fold standard deviations of the mean gray value of the negative controls on the basis of the negative control, we calculated the gray value of the cutoff line for N. meningitidis as 21.5, as shown with the dashed line in Figure 7b.
Figure 11 The dependence of mean gray value of EL images on J SC.
DO compute μ 1 and μ 2 as the mean gray level of each of the two classes obtained after thresholding the segmented slice with the threshold t 1 3.
DO compute μ 1 and μ 2 as the mean gray level of each of the two classes obtained after thresholding the segmented slice with the threshold t 1. DO compute the new threshold t 2 as the mean value of μ 1 and μ 2: t 2 = (μ 1 + μ 2)/2.
The cutoff value was determined as 3-fold standard deviations of the mean gray value of the negative controls on the basis of the negative control. Figure 3c clearly shows the difference between NC and PC and N. meningitidis.
Mean gray values of three regions of interests (ROIs; 100×75 µm) were analyzed: 1) on the vessel side of the postcapillary venule ipsilateral to the microinjection site, 2) on the contralateral side as well as 3) in the interstitial tissue 350 µm from the site of microinjection (considered as background) (depicted in the Fig 2B).
The formula used for background correction calculated the background-corrected intensity value as [(At*It)−(As*Is))/(At−As)], where At is the area of the total image, As is the area of the invaded spot, It is the mean gray intensity of the total image, and Is is the mean gray intensity of the invaded spot.
The image analysis of protein bands, computed as the ratio between the mean gray values of the prenylated vs nonprenylated band on Western blots of p21 rhoA, confirmed that fluvastatin significantly increased the amount of immature, nonisoprenylated protein in a concentration-dependent manner.
For each individually analysed cell three values were obtained: mean gray value of the PM, mean gray value of the entire cytosol and mean gray value of the cytosol lacking observable FM 4 64 staining (background intensity).
