[16] in which leptomeningeal and intracortical vessels are scored separately. Each section was assessed in a semiquantitative manner using a four-point scale (Grades 0–3): Grade 0 = no Aβ positive vessels Grade 1 = mild (that is, scattered involvement of a few vessels) Grade 2 = moderate (strong circumferential staining in a few vessels or scattered positivity in some vessels) Grade 3 = severe (widespread strong circumferential

staining) Attems et al. [16] employed a further grade of 4 to describe very severe vessel involvement with dyshoric change. However, in the present study, such cases were assigned Grade 3. The assessment Maraviroc cost protocol was further extended selleck kinase inhibitor to separately record the presence and severity

(1; mild, 2; moderate, 3; severe) of capillary amyloid deposition (capillary CAA). SP were scored as both diffuse and cored plaques according to their density (that is, severity). Diffuse deposits were those that appeared homogenous, irregularly shaped and without a well-demarcated outline or core. Cored plaques tended to be symmetrical in shape, well demarcated, and had a ‘cored’ appearance with a compacted central mass of Aβ. The severity was again assessed on a four-point scale (Grades 0–3): Grade 0 = absent Grade 1 = mild (few plaques in most low power (×10) fields) Grade 2 = moderate (moderate number to many plaques in all lower power (×10) fields) Grade 3 = severe (many plaques in all high power (×25) fields Following semiquantitatively grading of each section, four patterns of Aβ deposition (types 1–4) were defined microscopically according to the presence and distribution of Aβ within SP and/or CAA (see results). For every case, each topographical region

(frontal, temporal and occipital respectively) was assigned a specific phenotype (1, 2, 3 or 4), before and thereby each case was designated by a three digit code (that is, 122, 112, 222 etc.) according to the type of histological change present in each brain region. The semiquantitative data were entered into an excel spreadsheet and analysed using Statistical Package for Social Sciences (SPSS) software (version 17.0). Nonparametric testing (Kruskal–Wallis) was used to compare the semiquantitative ratings for SP (diffuse and cored), and CAA (leptomeningeal, parenchymal and capillary) across the four pathological phenotypes. Statistical significance was accepted at P < 0.05 level. When statistically significant, post-hoc analysis (Dunn’s test [17]) was performed with Bonferroni correction for multiple comparisons. Consequently, the corrected ‘P value’ level for this test was set at P < 0.0083. Group comparisons of age at onset, age at death, duration of illness and brain weight were made using anova, with post-hoc t-test being employed where results were significant.