MAOB and early-onset autosomal dominant Alzheimer disease: The search strategy was to use the following search terms in PubMed: “reactive astrocyte(s),” “positron emission tomography,” “monoamine oxidases-B,” “neurological disorders,” “Alzheimer’s disease,” “Parkinson’s disease,” “Amyotrophic lateral sclerosis,” “Multiple sclerosis” alone and in combination.