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- ItemAcesso aberto (Open Access)Aplicação da ressonância magnética de corpo inteiro para o estadiamento e acompanhamento de pacientes com linfoma de Hodgkin na faixa etária infanto-juvenil: comparação entre diferentes sequências(Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, 2011-02-01) Nava, Daniel [UNIFESP]; Oliveira, Heverton Cesar de [UNIFESP]; Luisi, Flavio Augusto [UNIFESP]; Ximenes, Andrea Regina Da Silveira; Lederman, Henrique Manoel [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Clínica CentrusOBJECTIVE: To compare the performance of the T1, T2, STIR and DWIBS (diffusion-weighted whole-body imaging with background body signal suppression) sequences in the staging and follow-up of pediatric patients with Hodgkin's lymphoma in lymph node chains, parenchymal organs and bone marrow, and to evaluate interobserver agreement. MATERIALS AND METHODS: The authors studied 12 patients with confirmed diagnosis of Hodgkin's lymphoma. The patients were referred for whole body magnetic resonance imaging with T1-weighted, T2-weighted, STIR and DWIBS sequences. RESULTS: The number of lymph node sites characterized as affected by the disease on T1- and T2-weighted sequences showed similar results (8 sites for both sequences), but lower than DWIBS and STIR sequences (11 and 12 sites, respectively). The bone marrow involvement by lymphoma showed the same values for the T1-, T2-weighted and DWIBS sequences (17 lesions), higher than the value found on STIR (13 lesions). A high rate of interobserver agreement was observed as the four sequences were analyzed. CONCLUSION: STIR and DWIBS sequences detected the highest number of lymph node sites characterized as affected by the disease. Similar results were demonstrated by all the sequences in the evaluation of parenchymal organs and bone marrow. A high interobserver agreement was observed as the four sequences were analyzed.
- ItemSomente MetadadadosBainitic precipitation in the Cu-9 wt.%Al-4 wt.%Mn-5 wt.%Ag alloy(Elsevier B.V., 2014-12-05) Adorno, A. T.; Carvalho, T. M.; Magdalena, A. G.; Santos, C. M. A. dos; Silva, R. A. G. [UNIFESP]; UNESP; Universidade Federal de São Paulo (UNIFESP)The isothermal kinetics of bainitic precipitation in the Cu-9 wt.%Al-4 wt.%Mn-5 wt.%Ag alloy was studied in the temperature range from 250 to 400 degrees C. the results indicated a diffusion controlled growth process with an activation energy value equal to that for alloys with high degree of order. the presence of Ag seems to enhance the Al diffusion from the matrix to precipitates. (C) 2014 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosConsensus Paper: Radiological Biomarkers of Cerebellar Diseases(Springer, 2015-04-01) Baldarcara, Leonardo [UNIFESP]; Currie, Stuart; Hadjivassiliou, M.; Hoggard, Nigel; Jack, Allison; Jackowski, Andrea P. [UNIFESP]; Mascalchi, Mario; Parazzini, Cecilia; Reetz, Kathrin; Righini, Andrea; Schulz, Joerg B.; Vella, Alessandra; Webb, Sara Jane; Habas, Christophe; Fed Univ Tocantins; Universidade Federal de São Paulo (UNIFESP); Univ Sheffield; Royal Hallamshire Hosp; Yale Univ; Univ Florence; Meyer Children & Careggi Hosp Florence; Childrens Hosp Buzzi; RWTH Aachen Univ Hosp; Forschungszentrum Julich; Julich Aachen Res Alliance JARA; Univ Hosp Siena; Univ Washington; CHNO Quinze VingtsHereditary and sporadic cerebellar ataxias represent a vast and still growing group of diseases whose diagnosis and differentiation cannot only rely on clinical evaluation. Brain imaging including magnetic resonance (MR) and nuclear medicine techniques allows for characterization of structural and functional abnormalities underlying symptomatic ataxias. These methods thus constitute a potential source of radiological biomarkers, which could be used to identify these diseases and differentiate subgroups of them, and to assess their severity and their evolution. Such biomarkers mainly comprise qualitative and quantitative data obtained from MR including proton spectroscopy, diffusion imaging, tractography, voxel-based morphometry, functional imaging during task execution or in a resting state, and from SPETC and PET with several radiotracers. in the current article, we aim to illustrate briefly some applications of these neuroimaging tools to evaluation of cerebellar disorders such as inherited cerebellar ataxia, fetal developmental malformations, and immune-mediated cerebellar diseases and of neurodegenerative or early-developing diseases, such as dementia and autism in which cerebellar involvement is an emerging feature. Although these radiological biomarkers appear promising and helpful to better understand ataxia-related anatomical and physiological impairments, to date, very few of them have turned out to be specific for a given ataxia with atrophy of the cerebellar system being the main and the most usual alteration being observed. Consequently, much remains to be done to establish sensitivity, specificity, and reproducibility of available MR and nuclear medicine features as diagnostic, progression and surrogate biomarkers in clinical routine.
- ItemSomente MetadadadosModeling of potassium sorbate diffusion through chitosan films(Elsevier B.V., 2010-05-01) Yoshida, Cristiana M. P. [UNIFESP]; Bastos, Carlos Eduardo N.; Franco, Telma T.; Universidade Estadual de Campinas (UNICAMP); Universidade Federal de São Paulo (UNIFESP)The mechanism of potassium sorbate (K-sorbate) release from chitosan films was studied as a function of immersion time in aqueous solution. Fick's law was applied to calculate the diffusion coefficient and the power law defining the type of diffusion mechanism. the novelty in this study is the compound diffusion mechanisms comparison through chitosan film (CF) and chitosan emulsion film Initially, the lipid was selected to obtain the emulsion films the evaluation was based oil the water vapor permeability (WVP) the lower WVP (32.45% less than chitosan film) Was found using 0 5 g/100 g of palmitic acid for 2.0 g/100 g of chitosan Then, active chitosan films (ACF) were obtained incorporating K-sorbate on CF at 0 1 and 0 5 g/100 g of K-sorbate Also, active palmitic acid-chitosan films (APEF) were obtained, incorporating 0 1 g/100 g of K-sorbate the mechanisms of K-sorbate diffusion through ACF and APEF were mainly non-Fickian. However, the K-sorbate diffusion coefficient did not reduced in lipid presence (C) 2009 Elsevier Ltd All rights reserved.