Figure 4.

Fluorescence spectra analysis of Aβ in cored and diffuse plaques labeled with qFTAA in different neocortex regions of rpAD and spAD cases. Mean emission spectra profiles of cored (A–C) and diffuse (D–F) plaques in the frontal, occipital, and temporal cortex of five rpAD (red) and 11 spAD (blue) randomly selected cases were labeled by qFTAA and recorded from 470 to 690 nm and expressed as a fluorescence intensity ratio of 500 to 510 nm (500/510 ratio) for compact (G) and diffuse (H) plaques, as described in the Experimental procedures section and Table S1. Each ratio data point represents one plaque; the full emission spectra of cored and diffuse plaques were recorded for each plaque in ten different spots, averaged, and normalized; bars indicate mean ± SD; ns; ∗∗p < 0.01, ∗∗∗∗p < 0.001. ns, not significant; qFTAA, quatroformylthiophene acetic acid; rpAD, rapidly progressive Alzheimer's disease; spAD, slowly progressive Alzheimer's disease.