ALEXANDRE TELES GARCEZ
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
2 resultados
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- Topography of C-11-Pittsburgh compound B uptake in Alzheimer's disease: a voxel-based investigation of cortical and white matter regions(2019) FARIA, Daniele de P.; DURAN, Fabio L.; SQUARZONI, Paula; COUTINHO, Artur M.; GARCEZ, Alexandre T.; SANTOS, Pedro P.; BRUCKI, Sonia M.; OLIVEIRA, Maira O. de; TRES, Eduardo S.; FORLENZA, Orestes V.; NITRINI, Ricardo; BUCHPIGUEL, Carlos A.; BUSATTO FILHO, GeraldoObjective: To compare results of positron emission tomography (PET) with carbon-11-labeled Pittsburgh compound B (C-11-PIB) obtained with cerebellar or global brain uptake for voxel intensity normalization, describe the cortical sites with highest tracer uptake in subjects with mild Alzheimer's disease (AD), and explore possible group differences in C-11-PIB binding to white matter. Methods: C-11-PIB PET scans were acquired from subjects with AD (n=17) and healthy elderly controls (n=19). Voxel-based analysis was performed with statistical parametric mapping (SPM). Results: Cerebellar normalization showed higher C-11-PIB uptake in the AD group relative to controls throughout the cerebral cortex, involving the lateral temporal, orbitofrontal, and superior parietal cortices. With global uptake normalization, greatest cortical binding was detected in the orbitofrontal cortex; decreased C-11-PIB uptake in white matter was found in the posterior hippocampal region, corpus callosum, pons, and internal capsule. Conclusion: The present case-control voxelwise C-11-PIB PET comparison highlighted the regional distribution of amyloid deposition in the cerebral cortex of mildly demented AD patients. Tracer uptake was highest in the orbitofrontal cortex. Decreased C-11-PIB uptake in white-matter regions in this patient population may be a marker of white-matter damage in AD.
- Brain PET amyloid and neurodegeneration biomarkers in the context of the 2018 NIA-AA research framework: an individual approach exploring clinical-biomarker mismatches and sociodemographic parameters(2020) COUTINHO, Artur Martins; BUSATTO, Geraldo F.; PORTO, Fabio Henrique de Gobbi; FARIA, Daniele de Paula; ONO, Carla Rachel; GARCEZ, Alexandre Teles; SQUARZONI, Paula; DURAN, Fabio Luiz de Souza; OLIVEIRA, Maira Okada de; TRES, Eduardo Sturzeneker; BRUCKI, Sonia Maria Dozzi; FORLENZA, Orestes Vicente; NITRINI, Ricardo; BUCHPIGUEL, Carlos AlbertoPurpose [F-18]FDG-PET and [C-11]PIB-PET are validated as neurodegeneration and amyloid biomarkers of Alzheimer's disease (AD). We used a PET staging system based on the 2018 NIA-AA research framework to compare the proportion of amyloid positivity (A+) and hypometabolism ((N)+) in cases of mild probable AD, amnestic mild cognitive impairment (aMCI), and healthy controls, incorporating an additional classification of abnormal [F-18]FDG-PET patterns and investigating the co-occurrence of such with A+, exploring [F-18]FDG-PET to generate hypotheses in cases presenting with clinical-biomarker ""mismatches."" Methods Elderly individuals (N = 108) clinically classified as controls (N = 27), aMCI (N = 43) or mild probable AD (N = 38) were included. Authors assessed their A(N) profiles and classified [F-18]FDG-PET neurodegenerative patterns as typical or non-typical of AD, performing re-assessments of images whenever clinical classification was in disagreement with the PET staging (clinical-biomarker ""mismatches""). We also investigated associations between ""mismatches"" and sociodemographic and educational characteristics. Results AD presented with higher rates of A+ and (N)+. There was also a higher proportion of A+ and (N)+ individuals in the aMCI group in comparison to controls, however without statistical significance regarding the A staging. There was a significant association between amyloid positivity and AD (N)+ hypometabolic patterns typical of AD. Non-AD (N)+ hypometabolism was seen in all A- (N)+ cases in the mild probable AD and control groups and [F-18]FDG-PET patterns classified such individuals as ""SNAP"" and one as probable frontotemporal lobar degeneration. All A- (N)- cases in the probable AD group had less than 4 years of formal education and lower socioeconomic status (SES). Conclusion The PET-based staging system unveiled significant A(N) differences between AD and the other groups, whereas aMCI and controls had different (N) staging, explaining the cognitive impairment in aMCI. [F-18]FDG-PET could be used beyond simple (N) staging, since it provided alternative hypotheses to cases with clinical-biomarker ""mismatches."" An AD hypometabolic pattern correlated with amyloid positivity. Low education and SES were related to dementia in the absence of biomarker changes.