MATERIALS AND METHODS: 18F-florbetapir PET and 18F-FDG PET imaging was prospectively performed on 78 subjects (20 cognitively healthy controls [HC], 27 MCI patients, and 31 AD patients) within 6 weeks of their neurocognitive assessments. The PET datasets from 19 HCs were used to create an NBD. The 3D-SSP analysis and Z-score mapping of 18F-florbetapir accumulations in the brain were further staged based on their accumulation patterns. Global and regional standard uptake value ratios (SUVRs) of 18Fflorbetapir were calculated using the cerebellar cortex as the normalised region. The relationships between the 18Fflorbetapir PET results, the clinical diagnoses and Thai Mini- Mental State Examination (TMSE) scores were determined.
RESULTS: There was high agreement between the visual assessment results and the semiquantitative analysis (κ = 0.793 and 0.845). The stages of amyloid deposition were consistent with neurocognitive status across participants. Significantly higher SUVRs were found in AD than MCI and HC. Visual assessment and stage were not significantly correlated with TMSE scores. A significant negative correlation between the SUVRs and TMSE scores was partially demonstrated in MCI and AD, but not HC.
CONCLUSIONS: 3D-SSP analysis of 18F-florbetapir PET provides special patterns and intensity of beta amyloid accumulation semi-quantitatively that are associated with the diagnosis and neurocognitive performances in MCI and AD patients.
METHODS: Different volumes of NaOCl were added to CHX (mix 1) or PCA (mix 2). Upon centrifugation, the supernatant and precipitate fractions collected from samples were analyzed using high-performance liquid chromatography. The cytotoxic effects of both fractions were examined on human periodontal ligament and 3T3 fibroblast cell lines.
RESULTS: High-performance liquid chromatographic analysis showed no PCA signal when NaOCl was mixed with CHX (mix 1). In mix 2, the intensity of PCA was decreased when NaOCl was added to PCA, and chromatographic signals, similar to that of CHX/NaOCl, were also observed. The mortality of precipitates exerted on both cell lines was lower compared with that of supernatants.
CONCLUSIONS: The discrepancy in the data from the literature could be caused by the instability of the PCA in the presence of NaOCl. The CHX/NaOCl reaction mixture exhibits a wide range of cytotoxic effects.