RESUMO
BACKGROUND: Glycolytic metabolism in the brain of pediatric patients, imaged with [18F] fluorodeoxyglucose-positron emission tomography (FDG-PET) is incompletely characterized. OBJECTIVE: The purpose of the current study was to characterize [18F]FDG-PET brain uptake in a large sample of pediatric patients with non-central nervous system diseases as an alternative to healthy subjects to evaluate changes at different pediatric ages. MATERIALS AND METHODS: Seven hundred ninety-five [18F]FDG-PET examinations from children < 18 years of age without central nervous system diseases were included. Each brain image was spatially normalized, and the standardized uptake value (SUV) was obtained. The SUV and the SUV relative to different pseudo-references were explored as a function of age. RESULTS: At all evaluated ages, the occipital lobe showed the highest [18F]FDG uptake (0.27 ± 0.04 SUV/year), while the parietal lobe and brainstem had the lowest uptake (0.17 ± 0.02 SUV/year, for both regions). An increase [18F]FDG uptake was found for all brain regions until 12 years old, while no significant uptake differences were found between ages 13 (SUV = 5.39) to 17 years old (SUV = 5.52) (P < 0.0001 for the whole brain). A sex dependence was found in the SUVmean for the whole brain during adolescence (SUV 5.04-5.25 for males, 5.68-5.74 for females, P = 0.0264). Asymmetries in [18F]FDG uptake were found in the temporal and central regions during infancy. CONCLUSIONS: Brain glycolytic metabolism of [18F]FDG, measured through the SUVmean, increased with age until early adolescence (< 13 years old), showing differences across brain regions. Age, sex, and brain region influence [18F]FDG uptake, with significant hemispheric asymmetries for temporal and central regions.
Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Masculino , Feminino , Adolescente , Humanos , Criança , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Voluntários Saudáveis , Compostos RadiofarmacêuticosRESUMO
BACKGROUND: Development of effective drugs for epilepsy are needed, as nearly 30 % of epileptic patients, are resistant to current treatments. This study is aimed to characterize the anticonvulsant effect of dapsone (DDS), in the kainic acid (KA)-induced Status Epilepticus (SE) by recording the brain metabolic activity with an [18F]FDG-PET analysis. METHODS: Wistar rats received KA (10 mg/kg, i.p., single dose) to produce sustained seizures. [18F]FDG-PET and electroencephalographic (EEG) studies were then performed. DDS or vehicle were administered 30 min before KA. [18F]FDG uptake and EEG were evaluated at baseline, 2 and 25 h after KA injection. Likewise, caspase-8, 3 hippocampal activities and Fluoro-Jade B neuronal degeneration and Hematoxylin-eosin staining were measured 25 h after KA. RESULTS: PET data evaluated at 2 h showed hyper-uptake of [18F]FDG in the control group, which was decreased by DDS. At 25 h, hypo-uptake was observed in the control group and higher values due to DDS effect. EEG spectral power was increased 2 h after KA administration in the control group during the generalized tonic-clonic seizures, which was reversed by DDS, correlated with [18F]FDG-PET uptake changes. The values of caspases-8 activity decreased 48 and 43 % vs control group in the groups treated with DDS (12.5 y 25 mg/kg respectively), likewise; caspase-3 activity diminished by 57 and 53 %. Fewer degenerated neurons were observed due to DDS treatments. CONCLUSIONS: This study pinpoints the anticonvulsant therapeutic potential of DDS. Given its safety and effectiveness, DDS may be a viable alternative for patients with drug-resistant epilepsy.
Assuntos
Epilepsia , Estado Epiléptico , Ratos , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Ácido Caínico/farmacologia , Fluordesoxiglucose F18/metabolismo , Dapsona/farmacologia , Ratos Wistar , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/tratamento farmacológico , Convulsões/metabolismo , Hipocampo/metabolismo , Epilepsia/metabolismoRESUMO
BACKGROUND: Poly-4-hydroxybutyrate (P4HB) is a naturally occurring polymer derived from transgenic E. coli bacteria with the longest degradation rate when compared to other available products. This polymer has been manufactured as a biosynthetic mesh to be used as reinforcement when repairing a variety of abdominal wall defects. OBJECTIVE: We aim to describe our center initial experience with this mesh and discuss the possible indications that may benefit from the use of P4HB mesh. METHODS: This is a descriptive retrospective study of patients who underwent abdominal wall repair with a P4HB mesh from October 2018 to December 2020 in a single, large volume, academic center. RESULTS: A total of 51 patients (mean age 54.4 years, range 12-89) underwent abdominal wall reconstruction with a P4HB mesh between October 2018 and December 2020. The mean BMI was 30.5 (range 17.2-50.6). Twenty-three (45%) patients had a prior hernia repair at the site. We grouped patients into six different indications for the use of P4HB mesh in our cohort: clean-contaminated, contaminated or infected field (57%), patient refusal for permanent meshes (14%), those with high risk for post-operative infection (12%), visceral protection of second mesh (10%), recurrence with related chronic pain from mesh (6%), and children (2%). Median follow-up was 105 days (range 8-648). Two patients had hernia recurrence (4%) and 8 (16%) patients developed seroma. CONCLUSION: P4HB mesh is a safe and a viable alternative for complex hernias and high-risk patients with a low complication rate in the short-term.
Assuntos
Parede Abdominal , Hérnia Ventral , Parede Abdominal/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Escherichia coli , Hérnia Ventral/cirurgia , Humanos , Hidroxibutiratos , Pessoa de Meia-Idade , Polímeros , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas , Resultado do Tratamento , Adulto JovemRESUMO
ABSTRACT Background Poly-4-hydroxybutyrate (P4HB) is a naturally occurring polymer derived from transgenic E. coli bacteria with the longest degradation rate when compared to other available products. This polymer has been manufactured as a biosynthetic mesh to be used as reinforcement when repairing a variety of abdominal wall defects. Objective: We aim to describe our center initial experience with this mesh and discuss the possible indications that may benefit from the use of P4HB mesh. Methods: This is a descriptive retrospective study of patients who underwent abdominal wall repair with a P4HB mesh from October 2018 to December 2020 in a single, large volume, academic center. Results: A total of 51 patients (mean age 54.4 years, range 12-89) underwent abdominal wall reconstruction with a P4HB mesh between October 2018 and December 2020. The mean BMI was 30.5 (range 17.2-50.6). Twenty-three (45%) patients had a prior hernia repair at the site. We grouped patients into six different indications for the use of P4HB mesh in our cohort: clean-contaminated, contaminated or infected field (57%), patient refusal for permanent meshes (14%), those with high risk for post-operative infection (12%), visceral protection of second mesh (10%), recurrence with related chronic pain from mesh (6%), and children (2%). Median follow-up was 105 days (range 8-648). Two patients had hernia recurrence (4%) and 8 (16%) patients developed seroma. Conclusion: P4HB mesh is a safe and a viable alternative for complex hernias and high-risk patients with a low complication rate in the short-term.
RESUMO Contexto: 4-Polihidroxibutirato (P4HB) é um polímero natural derivado da E. coli transgênica que tem a mais longa taxa de degradação quando comparado a outros produtos. Este polímero é manufaturado como uma tela biossintética a ser usada como um reforço no reparo de uma variedade de defeitos de parede abdominal. Objetivo: O objetivo deste estudo é descrever nossa experiência inicial com esta tela e discutir suas possíveis indicações. Métodos: Estudo retrospectivo e descritivo com pacientes que foram submetidos a cirurgia de reconstrução de parede abdominal de outubro de 2018 a dezembro de 2020 em um grande centro acadêmico. Resultados: Cinquenta e um pacientes, média de 54,4 anos (12-89) foram submetidos a reconstrução da parede abdominal com tela de P4HB entre outubro de 2018 e dezembro de 2020. O índice de massa corpórea médio foi de 30,5 kg/m2(17,2-50,6). Vinte e três pacientes (45%) tinham cirurgia prévia de hérnia no mesmo local. Nós agrupamos pacientes em seis diferentes indicações para o uso da tela de P4HB: campo limpo-contaminado, contaminado, infectado (57%), recusa do paciente em telas permanentes (14%), pacientes com alto risco de infecção no pós-operatório (12%), proteção visceral de contato com outra tela (10%), recidiva da hérnia associada com dor crônica relacionada a tela anterior (6%) e pacientes pediátricos (2%). O seguimento mediano foi de 105 dias (8-648). Dois pacientes tiveram recidiva (4%) e 8 (16%) desenvolveram seroma. Conclusão: O uso da tela de P4HB se mostrou uma alternativa segura e viável com baixa taxa de complicações para estes pacientes no curto prazo.
RESUMO
Animal models of Parkinson's disease are useful to evaluate new treatments and to elucidate the etiology of the disease. Hence, it is necessary to have methods that allow quantification of their effectiveness. [18 F]FDOPA-PET (FDOPA-PET) imaging is outstanding for this purpose because of its capacity to measure changes in the dopaminergic pathway noninvasively and in vivo. Nevertheless, PET acquisition and quantification is time-consuming making it necessary to find faster ways to quantify FDOPA-PET data. This study evaluated Male Wistar rats by FDOPA, before and after being partially injured with 6-OHDA unilaterally. MicroPET scans with a duration of 120 min were acquired and Patlak reference plots were created to estimate the influx constant Kc in the striatum using the full dynamic scan data. Additionally, simple striatal-to-cerebral ratios (SCR) of short static acquisitions were computed and compared with the Kc values. Good correlation (r > 0.70) was obtained between Kc and SCR, acquired between 80-120 min after FDOPA administration with frames of 10 or 20 min and both methods were able to separate the FDOPA-uptake of healthy controls from that of the PD model (SCR -28%, Kc -71%). The present study concludes that Kc and SCR can be trustfully used to discriminate partially lesioned rats from healthy controls.
Assuntos
Doença de Parkinson , Animais , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Di-Hidroxifenilalanina/metabolismo , Masculino , Oxidopamina/toxicidade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Ratos , Ratos WistarRESUMO
OBJECTIVE: Brain metabolic processes are not fully characterized in the kainic acid (KA)-induced Status Epilepticus (KASE). Thus, we evaluated the usefulness of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) as an experimental strategy to evaluate in vivo, in a non-invasive way, the glucose consumption in several brain regions, in a semi-quantitative study to compare and to correlate with data from electroencephalography and histology studies. METHODS: Sixteen male Wistar rats underwent FDG-PET scans at basal state and after KA injection. FDG-PET images were normalized to an MRI-based atlas and segmented to locate regions. Standardized uptake values (SUV) were obtained at several time points. EEGs and cell viability by histological analysis, were also evaluated. RESULTS: FDG-PET data showed changes in regions such as: amygdala, hippocampus, accumbens, entorhinal cortex, motor cortex and hypothalamus. Remarkably, hippocampal hypermetabolism was found (mean SUV = 2.66 ± 0.057) 2 h after KA administration, while hypometabolism at 24 h (mean SUV = 1.83 ± 0.056) vs basal values (mean SUV = 2.19 ± 0.057). EEG showed increased spectral power values 2 h post-KA administration. Hippocampal viable-cell counting 24 h after KA was decreased, while Fluoro-Jade B-positive cells were increased, as compared to control rats, coinciding with the hypometabolism detected in the same region by semi-quantitative FDG-PET at 24 h after KASE. CONCLUSIONS: PET is suitable to measure metabolic brain changes in the rat model of status epilepticus induced by KA (KASE) at the first 24 h, compared to that of EEG; PET data may also be sensitive to cell viability.
Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Antagonistas de Aminoácidos Excitatórios/farmacologia , Ácido Caínico/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Eletroencefalografia , Fluordesoxiglucose F18 , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Ratos , Ratos Wistar , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo , Estado Epiléptico/patologiaRESUMO
BACKGROUND: Positron emission tomography (PET) imaging in epilepsy is an in vivo technique that allows the localization of a possible seizure onset zone (SOZ) during the interictal period. Stereo-electro-encephalography (SEEG) is the gold standard to define the SOZ. The objective of this research was to evaluate the accuracy of PET imaging in localizing the site of SOZ compared with SEEG. METHODS: Seven patients with refractory temporal lobe epilepsy (Ep) and 2 healthy controls (HC) underwent 2 PET scans, one with 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) and another with 2'-[18F]fluoroflumazenil (FFMZ), acquired 1 day apart. FDG was acquired for 10 min (static scan) 1 h after administration. An FFMZ scan was acquired for 60 min from radiopharmaceutical administration in a dynamic mode. Each brain PET image was segmented using a standard template implemented in PMOD 3.8. The pons was used as the reference region for modeling of the nondisplaceable binding potential (BPND)for FFMZ, and to obtain uptake ratios for FDG. SEEG studies of patients were performed as a part of their surgical evaluation to define the SOZ. RESULTS: Well-defined differences between HC and Ep were found with both radiopharmaceuticals, showing the utility to identify abnormal brain regions using quantitative PET imaging. Lateralization of the SOZ findings by PET (lower uptake/binding in a specific brain hemisphere) matched in 86% for FFMZ and 71% for FDG with SEEG data. CONCLUSION: Quantitative PET imaging is an excellent complementary tool that matches reasonably well with SEEG to define SOZ in presurgical evaluation.
Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Flumazenil/análogos & derivados , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Adolescente , Adulto , Mapeamento Encefálico/métodos , Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/cirurgia , Feminino , Flumazenil/metabolismo , Radioisótopos de Flúor/metabolismo , Fluordesoxiglucose F18/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Convulsões/diagnóstico por imagem , Convulsões/metabolismo , Convulsões/cirurgiaRESUMO
OBJECTIVE: The aim of this work was to study mechanisms of action of electrical stimulation of prelemniscal radiations (Raprl) in the treatment of Parkinson disease, using 2-deoxy-2-fluoro-D-glucose (18F-FDG) Positron Emission Tomography (PET/CT). Materialand Methods: Five patients with PD and predominant unilateral tremor, rigidity and bradykinesia underwent deep brain stimulation (DBS) in contralateral Raprl that improved symptoms from 82.4 to 94.5%. 18F-FDG PET studies were performed before electrode implantation and after DBS therapy. Changes in metabolic activity in PET were evaluated by the maximal standardized uptake value (MSUV) and statistical parametric mapping (SPM) for regions of interest (ROIs) ipsilateral and contralateral to the stimulation site. ROIs were derived from a preoperative probabilistic tractography and included primary motor, supplementary motor and orbitofrontal cortices: Raprl, ventrolateral thalamus, putamen and cerebellum. RESULTS: No significant MSUV changes occurred in ROIs contralateral to Raprl-DBS. In contrast, MSUV decreased ipsilateral to DBS in Raprl, the thalamus, and the primary and supplementary motor cortices. SPM analysis showed metabolic changes which were significantly different after DBS therapy in all ROIs ipsilateral to DBS compared to those in the contralateral side. CONCLUSION: Raprl-DBS decreases the metabolic activity of areas anatomically related to its fiber composition. Improvement of symptoms may result from a decrease in pathological overactivity of circuits related to the ROIs.
Assuntos
Encéfalo/metabolismo , Hipocinesia/terapia , Doença de Parkinson/terapia , Tremor/terapia , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda/métodos , Feminino , Humanos , Hipocinesia/diagnóstico por imagem , Hipocinesia/metabolismo , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Cintilografia , Resultado do Tratamento , Tremor/diagnóstico por imagem , Tremor/metabolismoRESUMO
Contiene: Causas y motivos para la realizacion de la marcha - Dos sectores salen en defensa y solidaridad - Reaccion por un parte de ellas al conocer la accion de realizar la marcha - Una voz expresada elocuentemente - Encabezamiento de la marcha - Los primeros movimientos internos en la marcha - Solidaridad con la marcha - Historico encuentro - Segundo pronunciamiento de la iglesia Catolica - Las demandas de los marchistas se politizan - Evo morales sale al frente en defensa de la marcha - Cocaleras llegan, ya estan hoy en la ciudad de La Paz - Comedores populares