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
17 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 17
- A medicina nuclear no Sistema Único de Saúde no Brasil(2014) BUCHPIGUEL, Carlos Alberto
- The link between cardiovascular risk, Alzheimer's disease, and mild cognitive impairment: support from recent functional neuroimaging studies(2014) FERREIRA, Luiz K.; TAMASHIRO-DURAN, Jaqueline H.; SQUARZONI, Paula; DURAN, Fabio L.; ALVES, Tania C.; BUCHPIGUEL, Carlos A.; BUSATTO, Geraldo F.Objective: To review functional neuroimaging studies about the relationship between cardiovascular risk factors (CVRFs), Alzheimer's disease (AD), and mild cognitive impairment (MCI). Methods: We performed a comprehensive literature search to identify articles in the neuroimaging field addressing CVRF in AD and MCI. We included studies that used positron emission tomography (PET), single photon emission computerized tomography (SPECT), or functional magnetic resonance imaging (fMRI). Results: CVRFs have been considered risk factors for cognitive decline, MCI, and AD. Patterns of AD-like changes in brain function have been found in association with several CVRFs (both regarding individual risk factors and also composite CVRF measures). In vivo assessment of AD-related pathology with amyloid imaging techniques provided further evidence linking CVRFs and AD, but there is still limited information resulting from this new technology. Conclusion: There is a large body of evidence from functional neuroimaging studies supporting the hypothesis that CVRFs may play a causal role in the pathophysiology of AD. A major limitation of most studies is their cross-sectional design; future longitudinal studies using multiple imaging modalities are expected to better document changes in CVRF-related brain function patterns and provide a clearer picture of the complex relationship between aging, CVRFs, and AD.
- 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.
- Long-Term Lithium Treatment Reduces Glucose Metabolism in the Cerebellum and Hippocampus of Nondemented Older Adults: An [F-18]FDG-PET Study(2014) FORLENZA, Orestes V.; COUTINHO, Artur Martins Novaes; APRAHAMIAN, Ivan; PRANDO, Silvana; MENDES, Luciana Lucas; DINIZ, Breno S.; GATTAZ, Wagner F.; BUCHPIGUEL, Carlos A.Lithium modulates several intracellular pathways related to neuroplasticity and resilience against neuronal injury. These properties have been consistently reported in experimental models, and involve the up-regulation of neurotrophic response and autophagy, and down-regulation of apoptosis, oxidative stress, and inflammation. Clinical and epidemiological studies in bipolar disorder show that acute treatment with lithium increases plasma concentrations of brain-derived neurotrophic factor, and long-term treatment lowers the risk of dementia. Neuroimaging studies indicate that lithium use is further associated with increased cortical thickness and larger hippocampal volumes. The objective of the present study was to evaluate whether these neurobiological properties of lithium reflect in increased regional brain glucose metabolism, as shown by [F-18]FDG-PET. Participants (n = 19) were nondemented older adults recruited at the end point of a controlled trial addressing clinical and biological effects of lithium in a sample of patients with amnestic mild cognitive impairment. Twelve patients who had received low-dose lithium carbonate for 4 years were compared to seven matched controls. Chronic lithium treatment was not associated with any significant increase in brain glucose metabolism in the studied areas. Conversely, we found a significant reduction in glucose uptake in several clusters of the cerebellum and in both hippocampi. These findings were not associated with any clinical evidence of toxicity. The clinical implications of the present findings need to be clarified by future controlled studies, particularly in the light of the potential use of lithium as a disease-modifying treatment approach for certain neurodegenerative disorders, namely, Alzheimer's disease and amyotrophic lateral sclerosis.
conferenceObject CONSOLIDATION CHEMOTHERAPY DURING EXTENDED CRT LEADS TO SUSTAINED DECREASE IN TUMOR METABOLISM WHEN COMPARED TO STANDARD CRT REGIMEN(2014) HABR-GAMA, A.; PEREZ, R.; JULIAO, G. Sao; LYNN, P.; GAMA-RODRIGUES, J.; PROSCURSHIM, I.; BUCHPIGUEL, C.conferenceObject FEASIBILITY OF THERAPEUTIC I131 METAIODOBENZYLGUANIDINE (MIBG) PREVIOUS TO BLOOD STEM CELL COLLECTION AS ""PURGING IN VIVO"" FOR HIGH-RISK NEUROBLASTOMAS (HRNB)(2014) ODONE-FILHO, V.; ALMEIDA, M. T. A.; BUCHPIGEL, C.; AZAMBUJA, A. M. P.; VINCE, C. S. C.; BRUMATTI, M.; NEVES, N. S. H.; BATISTA, G. L. F.; MALUF JR., P. T.; CRISTOFANI, L. M. C.- Changes in Neuropsychological Tests and Brain Metabolism After Bariatric Surgery(2014) MARQUES, Emerson Leonildo; HALPERN, Alfredo; MANCINI, Marcio Correa; MELO, Maria Edna de; HORIE, Ndia Celeste; BUCHPIGUEL, Carlos Alberto; COUTINHO, Artur Martins Novaes; ONO, Carla Rachel; PRANDO, Silvana; SANTO, Marco Aurelio; CUNHA-NETO, Edecio; FUENTES, Daniel; CERCATO, CintiaContext: The mechanisms by which obesity alters the cerebral function and the effect of weight loss on the brain have not been completely clarified. Objective: The objective of the study was to assess the effect of bariatric surgery on the cognitive function and cerebral metabolism. Design: Seventeen obese women were studied prior to and 24 weeks after bariatric surgery using neuropsychological tests and positron emission tomography. Setting: The study was conducted in a reference center for the treatment of obesity of a Brazilian public university. Participants: Thirty-three women paired by age and level of education made up two groups: 17 severely obese patients and 16 lean patients. They did not have diabetes mellitus or a family history of dementia. Main Outcome Measures: Comparison of performance in neuropsychological tests and cerebral metabolism of the obese women before and after bariatric surgery was measured. The results found at the two moments were compared with those of the women of normal weight. Results: Women with a mean age of 40.5 years and mean body mass index of 50.1 kg/m(2) when compared with women with mean body mass index of 22.3 kg/m(2) showed increased cerebral metabolism, especially in the posterior cingulate gyrus (P <.004). No difference was found between the groups for the neuropsychological tests. After 24 weeks the cerebral metabolism of the obese women was lower, similar to the lean women, and there was an improvement of executive function, accompanying changes of metabolic and inflammatory parameters. Conclusions: Obese women may have increased cerebral metabolism when compared with women of normal weight, and this appears to reverse after weight loss induced by bariatric surgery, accompanied by improved executive function.
- 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.
- Graves' disease radioiodine-therapy: Choosing target absorbed doses for therapy planning(2014) WILLEGAIGNON, J.; SAPIENZA, M. T.; COURA-FILHO, G. B.; WATANABE, T.; TRAINO, A. C.; BUCHPIGUEL, C. A.Purpose: The precise determination of organ mass (m(th)) and total number of disintegrations within the thyroid gland ((A) over tilde) are essential for thyroid absorbed-dose calculations for radioiodine therapy. Nevertheless, these parameters may vary according to the method employed for their estimation, thus introducing uncertainty in the estimated thyroid absorbed dose and in any dose-response relationship derived using such estimates. In consideration of these points, thyroid absorbed doses for Graves' disease (GD) treatment planning were calculated using different approaches to estimating the m(th) and the (A) over tilde. Methods: Fifty patients were included in the study. Thyroid I-131 uptake measurements were performed at 2, 6, 24, 48, 96, and 220 h postadministration of a tracer activity in order to estimate the effective half-time (T-eff) of I-131 in the thyroid; the thyroid cumulated activity was then estimated using the Teff thus determined or, alternatively, calculated by numeric integration of the measured time-activity data. Thyroid mass was estimated by ultrasonography (USG) and scintigraphy (SCTG). Absorbed doses were calculated with the OLINDA/EXM software. The relationships between thyroid absorbed dose and therapy response were evaluated at 3 months and 1 year after therapy. Results: The average ratio (+/- 1 standard deviation) between m(th) estimated by SCTG and USG was 1.74 (+/- 0.64) and that between (A) over tilde obtained by Teff and the integration of measured activity in the gland was 1.71 (+/- 0.14). These differences affect the calculated absorbed dose. Overall, therapeutic success, corresponding to induction of durable hypothyroidism or euthyroidism, was achieved in 72% of all patients at 3 months and in 90% at 1 year. A therapeutic success rate of at least 95% was found in the group of patients receiving doses of 200 Gy (p = 0.0483) and 330 Gy (p = 0.0131) when m(th) was measured by either USG or SCTG and (A) over tilde was determined by the integration of measured I-131 activity in the thyroid gland and based on T-eff, respectively. No statistically significant relationship was found between therapeutic response and patients' age, administered I-131 activity (MBq), 24-h thyroid I-131 uptake (%) or T-eff (p >= 0.064); nonetheless, a good relationship was found between the therapeutic response and mth (p >= 0.035). Conclusions: According to the results of this study, the most effective thyroid absorbed dose to be targeted in GD therapy should not be based on a fixed dose but rather should be individualized based on the patient's m(th) and (A) over tilde. To achieve a therapeutic success (i.e., durable euthyroidism or hypothyroidism) rate of at least 95%, a thyroid absorbed dose of 200 or 330 Gy is required depending on the methodology used for estimating m(th) and (A) over tilde. (C) 2014 American Association of Physicists in Medicine.
conferenceObject Gene and Protein Expression Analysis of GLUT1 and HK2 in Primary Macronodular Adrenocortical Hyperplasia with High 18F-FDG Uptake in PET/CT(2014) CAVALCANTE, Isadora Pontes; ALENCAR, Guilherme Asmar; MARIANI, Beatriz M. P.; MURAD, Andre Faria; ALMEIDA, Madson Q.; BUCHPIGUEL, Carlos Alberto; LERARIO, Antonio M.; ZERBINI, Maria Claudia N.; MENDONCA, Berenice B.; FRAGOSO, Maria Candida B. V.