Cell Cycle Activation in Neurons -- Paved with Good Intentions -- The Role of Presenilins in the Cell Cycle and Apoptosis -- Cell Cycle Activation and Cell Death in the Nervous System -- Cell Cycle and Chromosome Segregation Defects in Alzheimer’s Disease -- Alzheimer Disease -- From Cell Cycle Activation to the Inhibition of the Wnt Pathway.Cell-Cycle Mechanisms and Neuronal Cell Death exami…