CARLOS ALBERTO BUCHPIGUEL
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina - Líder
20 resultados
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conferenceObject C-11-pib pet showed a distinct cerebrospinal fluid pattern in patients with progressive multiple sclerosis(2020) PITOMBEIRA, M.; DURAN, F.; CAMPANHOLO, K.; SOUZA, A.; APOSTOLOS-PEREIRA, S.; RIMKUS, C. Medeiros; MENDES, M. F.; BUSATTO FILHO, G.; CALLEGARO, D.; BUCHPIGUEL, C.; FARIA, D. De Paula- PET imaging of demyelination and remyelination in the cuprizone mouse model for multiple sclerosis: A comparison between [C-11]CIC and [C-11]MeDAS(2014) FARIA, Daniele de Paula; VRIES, Erik F. J. de; SIJBESMA, Jurgen W. A.; DIERCKX, Rudi A. J. O.; BUCHPIGUEL, Carlos A.; COPRAY, SjefMultiple Sclerosis (MS) is a neurodegenerative disease characterized by demyelinated lesions. PET imaging using specific myelin radioligands might solve the lack of a specific imaging tool for diagnosing and monitoring demyelination and remyelination in MS patients. In recent years, a few tracers have been developed for in vivo PET imaging of myelin, but they have not been fully evaluated yet. In this study, we compared [C-11]CIC and [C-11]MeDAS as PET tracers for monitoring demyelination and remyelination in cuprizone-fed mice. The ex vivo biodistribution of [C-11]CIC showed decreased tracer uptake in mice fed with 0.2% cuprizone diet for 5 weeks, as compared to control mice. However, tracer uptake did not increase again after normal diet was restored for 5 weeks (remyelination). Surprisingly, in vivo PET imaging with [C-11]CIC in cuprizone-fed mice revealed a significant reduction in whole brain tracer uptake after 5 weeks of remyelination. No correlation between ex vivo biodistribution and in vivo imaging data was found for [C-11]CIC (r(2) = 0.15, p = 0.11). However, a strong correlation was found for [C-11]MeDAS (r(2) = 0.88, p < 0.0001). [C-11]MeDAS ex vivo biodistribution revealed significant decreased brain uptake in the demyelination group, as compared to controls and increased the tracer uptake after 5 weeks of remyelination. [C-11]MeDAS images showed a low background signal and clear uptake in the brain white matter and spinal cord. Taken together, the results of this comparative study between [C-11]CIC and [C-11] MeDAS clearly show that [C-11]MeDAS is the preferred PET tracer to monitor myelin changes in the brain and spinal cord in vivo.
- 11C-PK11195 plasma metabolization has the same rate in multiple sclerosis patients and healthy controls: a cross-sectional study(2021) SOUZA, Aline Morais de; PITOMBEIRA, Milena Sales; SOUZA, Larissa Estessi de; MARQUES, Fabio Luiz Navarro; BUCHPIGUEL, Carlos Alberto; REAL, Caroline Cristiano; FARIA, Daniele de Paula11C-PK11195 is a positron emitter tracer used for Positron Emission Tomography (PET) imaging of innate immune cell activation in studies of neuroinflammatory diseases. For the image quantitative analysis, it is necessary to quantify the intact fraction of this tracer in the arterial plasma during imaging acquisition (plasma intact fraction). Due to the complexity and costs involved in this analysis it is important to evaluate the real necessity of individual analysis in each 11C-PK11195 PET imaging acquisition. The purpose of this study is to compare 11C-PK11195 plasma metabolization rate between healthy controls and multiple sclerosis (MS) patients and evaluate the interference of sex, age, treatment, and disease phenotype in the tracer intact fraction measured in arterial plasma samples. 11C-PK11195 metabolization rate in arterial plasma was quantified by high performance liquid chromatography in samples from MS patients (n = 50) and healthy controls (n = 23) at 20, 45, and 60 minutes after 11C-PK11195 injection. Analyses were also stratified by sex, age, treatment type, and MS phenotype. The results showed no significant differences in the metabolization rate of healthy controls and MS patients, or in the stratified samples. In conclusion, 11C-PK11195 metabolization has the same rate in patients with MS and healthy controls, which is not affected by sex, age, treatment, and disease phenotype. Thus, these findings could contribute to exempting the necessity for tracer metabolization determination in all 11C-PK11195 PET imaging acquisition, by using a population metabolization rate average. The study procedures were approved by the Ethics Committee for Research Projects Analysis of the Hospital das Clinicas of the University of Sao Paulo Medical School (approval No. 624.065) on April 23, 2014.
- Metabolic and Structural Signatures of Speech and Language Impairment in Corticobasal Syndrome: A Multimodal PET/MRI Study(2021) PARMERA, Jacy Bezerra; ALMEIDA, Isabel Junqueira de; OLIVEIRA, Marcos Castello Barbosa de; SILAGI, Marcela Lima; CARNEIRO, Camila de Godoi; STUDART-NETO, Adalberto; ONO, Carla Rachel; BARBOSA, Egberto Reis; NITRINI, Ricardo; BUCHPIGUEL, Carlos Alberto; BRUCKI, Sonia Maria Dozzi; COUTINHO, Artur MartinsIntroduction: Corticobasal syndrome (CBS) is a progressive neurological disorder related to multiple underlying pathologies, including four-repeat tauopathies, such as corticobasal degeneration and progressive supranuclear palsy, and Alzheimer's disease (AD). Speech and language are commonly impaired, encompassing a broad spectrum of deficits. We aimed to investigate CBS speech and language impairment patterns in light of a multimodal imaging approach. Materials and Methods: Thirty-one patients with probable CBS were prospectively evaluated concerning their speech-language, cognitive, and motor profiles. They underwent positron emission tomography with [F-18]fluorodeoxyglucose (FDG-PET) and [C-11]Pittsburgh Compound-B (PIB-PET) on a hybrid PET-MRI machine to assess their amyloid status. PIB-PET images were classified based on visual and semi-quantitative analyses. Quantitative group analyses were performed on FDG-PET data, and atrophy patterns on MRI were investigated using voxel-based morphometry (VBM). Thirty healthy participants were recruited as imaging controls. Results: Aphasia was the second most prominent cognitive impairment, presented in 67.7% of the cases, following apraxia (96.8%). We identified a wide linguistic profile, ranging from nonfluent variant-primary progressive aphasia to lexical-semantic deficits, mostly with impaired verbal fluency. PIB-PET was classified as negative (CBS-A- group) in 18/31 (58%) and positive (CBS-A+ group) in 13/31 (42%) patients. The frequency of dysarthria was significantly higher in the CBS-A- group than in the CBS-A+ group (55.6 vs. 7.7%, p = 0.008). CBS patients with dysarthria had a left-sided hypometabolism at frontal regions, with a major cluster at the left inferior frontal gyrus and premotor cortex. They showed brain atrophy mainly at the opercular frontal gyrus and putamen. There was a positive correlation between [F-18]FDG uptake and semantic verbal fluency at the left inferior (p = 0.006, R-2 = 0.2326), middle (0.0054, R-2 = 0.2376), and superior temporal gyri (p = 0.0066, R-2 = 0.2276). Relative to the phonemic verbal fluency, we found a positive correlation at the left frontal opercular gyrus (p = 0.0003, R-2 = 0.3685), the inferior (p = 0.0004, R-2 = 0.3537), and the middle temporal gyri (p = 0.0001, R-2 = 0.3993). Discussion: In the spectrum of language impairment profile, dysarthria might be helpful to distinguish CBS patients not related to AD. Metabolic and structural signatures depicted from this feature provide further insights into the motor speech production network and are also helpful to differentiate CBS variants.
- Paraneoplastic limbic encephalitis with prominent neuropsychiatric apathy(2014) PORTO, Fabio Hernique de Gobbi; COUTINHO, Artur Martins Novaes; LUCATO, Leandro Tavares; SPINDOLA, Livia; ONO, Carla Rachel; BRUCKI, Sonia Maria Dozzi; BUCHPIGUEL, Carlos Alberto; NITRINI, RicardoThe spectrum of paraneoplastic neurologic syndromes has increased with the description of encephalitis associated with antibodies against cell surface and synaptic proteins. Subacute cognitive impairment, movement disorders, late onset epilepsy and neuropsychiatric syndromes were recently linked to paraneoplastic encephalitis. Despite that, probably some syndromes and antibodies are yet to be reported. Herein we reported the clinical and neuroimaging pictures of a patient with late onset medial temporal lobe epilepsy, subtle cognitive impairment, psychosis and severe apathy diagnosed with antibody-negative paraneoplastic encephalitis due to colonic adenocarcinoma. The apathy markedly improved after removal of the tumor, without concomitant immunotherapy (steroids, intravenous immunoglobulins, immunosuppressants, plasmapheresis, etc). Our report highlights the importance of a full clinical and neurologic investigation in cases of atypical neuropsychiatric presentations, particularly in the elderly and with the concomitance of epilepsy and cognitive decline. Even chronic presentations must be considered. Neuroimaging is an important tool to demonstrate structural and functional brain dysfunction in these cases. Colonic adenocarcinoma should be searched for in cases in which a typical tumor related to paraneoplastic neurologic syndromes is not found.
- Brain metabolism and cerebrospinal fluid biomarkers profile of non-amnestic mild cognitive impairment in comparison to amnestic mild cognitive impairment and normal older subjects(2015) COUTINHO, Artur M. N.; PORTO, Fabio H. G.; DURAN, Fabio L. S.; PRANDO, Silvana; ONO, Carla R.; FEITOSA, Esther A. A. F.; SPINDOLA, Livia; OLIVEIRA, Maira O. de; VALE, Patricia H. F. do; GOMES, Helio R.; NITRINI, Ricardo; BRUCKI, Sonia M. D.; BUCHPIGUEL, Carlos A.Introduction: Mild cognitive impairment (MCI) is classically considered a transitional stage between normal aging and dementia. Non-amnestic MCI (naMCI) patients, however, typically demonstrate cognitive deficits other than memory decline. Furthermore, as a group, naMCI have a lower rate of an eventual dementia diagnosis as compared to amnestic subtypes of MCI (aMCI). Unfortunately, studies investigating biomarker profiles of naMCI are scarce. The study objective was to investigate the regional brain glucose metabolism (rBGM) with [F-18]FDG-PET and cerebrospinal fluid (CSF) biomarkers in subjects with naMCI as compared to a control group (CG) and aMCI subjects. Methods: Ninety-five patients were included in three different groups: naMCI (N = 32), aMCI (N = 33) and CG (N = 30). Patients underwent brain MRI and [F-18]FDG-PET. A subsample (naMCI = 26, aMCI = 28) also had an assessment of amyloid-beta, tau, and phosphorylated tau levels in the CSF. Results: Both MCI groups had lower rBGM in relation to the CG in the precuneus. Subjects with naMCI showed decreased right prefrontal metabolism as well as higher levels of CSF amyloid-beta relative to aMCI subjects. Conclusion: While amnestic MCI subjects showed a biomarker profile classically related to MCI due to Alzheimer's disease, naMCI patients illustrated a decrease in both prefrontal hypometabolism and higher CSF amyloid-beta levels relative to the aMCI group. These biomarker findings indicate that naMCI is probably a heterogeneous group with similar precuneus hypometabolism compared to aMCI, but additional frontal hypometabolism and less amyloid-beta deposition in the brain. Clinical follow-up and reappraisal of biomarkers of the naMCI group is needed to determine the outcome and probable etiological diagnosis.
- PET imaging in multiple sclerosis(2014) FARIA, Daniele de Paula; COPRAY, Sjef; BUCHPIGUEL, Carlos; DIERCKX, Rudi; VRIES, Erik dePositron emission tomography (PET) is a non-invasive technique for quantitative imaging of biochemical and physiological processes in animals and humans. PET uses probes labeled with a radioactive isotope, called PET tracers, which can bind to or be converted by a specific biological target and thus can be applied to detect and monitor different aspects of diseases. The number of applications of PET imaging in multiple sclerosis is still limited. Clinical studies using PET are basically focused on monitoring changes in glucose metabolism and the presence of activated microglia/macrophages in sclerotic lesions. In preclinical studies, PET imaging of targets for other processes, like demyelination and remyelination, has been investigated and may soon be translated to clinical applications. Moreover, more PET tracers that could be relevant for MS are available now, but have not been studied in this context yet. In this review, we summarize the PET imaging studies performed in multiple sclerosis up to now. In addition, we will identify potential applications of PET imaging of processes or targets that are of interest to MS research, but have yet remained largely unexplored.
- New Perspectives in Nuclear Neurology for the Evaluation of Parkinson's Disease(2013) BENADIBA, Marcel; LUURTSEMA, Gert; TUMAS, Vitor; BUCHPIGEL, Carlos Alberto; BUSATTO, Geraldo F.The pathophysiology of Parkinson's disease (PD) has not yet been completely elucidated. However, during the past few years, significant progress has been made in understanding the intra- and extracellular mechanisms by which proteins such as alpha-synuclein and neuroinflammatory molecules may display impaired function and/or expression in PD. Recent developments in imaging techniques based on positron emission tomography (PET) and single photon emission computed tomography (SPECT) now allow the non-invasive tracking of such molecular targets of known relevance to PD in vivo. This article summarizes recent PET and SPECT studies of new radiopharmaceuticals and discusses their potential role and perspectives for use in the fields of new drug development and early diagnosis for PD, as well to aid in differential diagnosis and monitoring of the progression of PD.
- Effects of aerobic training on cognition and brain glucose metabolism in subjects with MCI(2015) PORTO, F.; COUTINHO, A.; PINTO, A.; GUALANO, B.; DURAN, F.; PRANDO, S.; ONO, C.; SPINDOLA, L.; OLIVEIRA, M. de; VALE, P. do; NITRINI, R.; BUCHPIGUEL, C.; BRUCKI, S.
- Deficits in short-term memory binding are detectable in individuals with brain amyloid deposition in the absence of overt neurodegeneration in the Alzheimer's disease continuum(2021) CECCHINI, Mario Amore; YASSUDA, Monica Sanches; SQUARZONI, Paula; COUTINHO, Artur Martins; FARIA, Daniele de Paula; DURAN, Fabio Luiz de Souza; COSTA, Naomi Antunes da; PORTO, Fabio Henrique de Gobbi; NITRINI, Ricardo; FORLENZA, Orestes Vicente; BRUCKI, Sonia Maria Dozzi; BUCHPIGUEL, Carlos Alberto; PARRA, Mario A.; BUSATTO, Geraldo F.The short-term memory binding (STMB) test involves the ability to hold in memory the integration between surface features, such as shapes and colours. The STMB test has been used to detect Alzheimer's disease (AD) at different stages, from preclinical to dementia, showing promising results. The objective of the present study was to verify whether the STMB test could differentiate patients with distinct biomarker profiles in the AD continuum. The sample comprised 18 cognitively unimpaired (CU) participants, 30 mild cognitive impairment (MCI) and 23 AD patients. All participants underwent positron emission tomography (PET) with Pittsburgh compound B labelled with carbon-11 ([C-11]PIB) assessing amyloid beta (A beta) aggregation (A) and 18fluorine-fluorodeoxyglucose ([F-18]FDG)-PET assessing neurodegeneration (N) (A -N-[n = 35]); A+N-[n = 11]; A+ N+ [n = 19]). Participants who were negative and positive for amyloid deposition were compared in the absence (A-N vs. A+N-) of neurodegeneration. When compared with the RAVLT and SKT memory tests, the STMB was the only cognitive task that differentiated these groups, predicting the group outcome in logistic regression analyses. The STMB test showed to be sensitive to the signs of AD pathology and may represent a cognitive marker within the AD continuum.