Antisera to Beta amyloid (β APP) precursor protein strongly labeled neurons in some cases (Panel A, Case #12, 200× magnification). In the majority of the cases, β APP staining was entirely absent or showed a single focus of staining. Case #16 showed a focal cluster of perivascular staining (Panel B, 400× magnification) in one brain region and an individual swelling in another (Panel C, also Case #16, 400× magnification). Although definite staining, these were not considered significant with regard to evidence of inflicted injury (see Results and Case Reviews).