Ratio of CD8, CD68 and P24 between HAD and HIV non-dementia patients. The mean value of the log-transformed CD8, CD68 and P24 data for each patient in each region was calculated and analyzed with two-tailed tests with a significance level of 5% (Because several zero counts were observed, one was added to the observed count prior to log transformation). In order to show the difference of value in different regions, only the ratio of mean value has been shown between HAD and HIV non-dementia patients. For CD8, there was significant difference between HAD and HIV non-dementia patients in the basal ganglia and parietal regions (P < 0.05), for CD68, the difference was observed in basal ganglia, parietal and mid brain (P < 0.05), whereas for P24 antigen, every region showed statistically significant difference, which is exemplified by the absence of P24 antigen in all HIV non-dementia patients (P < 0.05). M: mid brain, T: temporal lobe, B: basal ganglia, H: hippocampus, MED: medulla, C: cerebellum, F: frontal lobe, P: parietal lobe, O: occipital lobe.