Figure 6.

Comparative spectral analysis of Aβ in diffuse plaque morphotypes labeled with hFTAA in different regions of rpAD and spAD cases. Normalized mean fluorescence emission spectra of diffuse plaques in different regions of five rpAD (red) and 11 spAD (blue) cases labeled by hFTAA and recorded from 470 to 690 nm (A–C) as described in the Experimental procedures section and Table S1. D–G, normalized fluorescence intensity ratios for distinct peaks were evaluated. Each data point represents one diffuse plaque, full spectrum was recorded in 10 different regions of interest, averaged, and normalized. Emission wavelength ratios of individual plaques, each averaged from 10 recording spots, are expressed as means ± SD; ns; ∗∗∗p < 0.005, ∗∗∗∗p < 0.001. hFTAA, heptaformylthiophene acetic acid; ns, not significant; rpAD, rapidly progressive Alzheimer's disease; spAD, slowly progressive Alzheimer's disease.