Navegando por Palavras-chave "Meios de contraste"
Agora exibindo 1 - 10 de 10
Resultados por página
Opções de Ordenação
- ItemAcesso aberto (Open Access)Alterações na expressão protéica das células mesangiais em cultura sob os efeitos quimiotóxicos do meio de contraste radiológico iodado, HexabrixR.(Universidade Federal de São Paulo (UNIFESP), 2006-12-31) Perez, Juliana Dinéia [UNIFESP]; Casarini, Dulce Elena [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The kidney is a common target organ for toxic agents, like contrast media (CM). The CM with iodine is normally used in angiography, urography and tomography. CM is filtrated and metabolized in the kidney, being the major cause of acute renal failure (ARF). Nowadays, proteome is actually a powerful tool in the Nephrology Research, mainly in the identification of protein modifications when in contact with toxic agents. This technique also gives the possibility of biomarkers identification to help the physicians in the patient treatments. The aim of this study was to separate by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and to identify by matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry the proteins that were up- or down-regulated in immortalized mesangial cell in culture (IMC) in the presence of CM. We evaluated three groups of IMC: control (CT), manitol (Man) and HexabrixTM (Hx). The samples were treated and submitted to the 2D-PAGE analysis, where the proteins were separated according to their isoelectric points and molecular weights. We identified by MALDI-TOF around 11 proteins. Some proteins were expressed only in the Hx group (Proliferating Cell Nuclear Antigen and Masp 1); others were more expressed in the Man group when compared with Hx and Ct groups (Translationally Controlled Tumor Protein). On the other hand, some proteins were expressed only in the Ct and Man groups (Annexin A3 and DNA ligase), suggesting that probably the Hx caused injury in these cells and it was responsible for the down-regulation of these proteins. Finally, we identified proteins that were expressed in the three cell groups (Heat Shock Protein 27, Heat Shock Protein 84), but with different levels. We concluded that the osmolarity of manitol and Hx could influenciate the alterations in the concentration of a specific protein. We believe that osmolarity and other factors of the CM could be responsible for the nephrotoxicity observed in this model. Proteomic analysis is a promising tool to study the renal pathophysiology making possible in the future the identification of biomarkers of renal diseases that can constitute therapeutically targets, minimizing the actual damages for the ARF.
- ItemSomente MetadadadosAvaliação da nefrotoxicidade do contraste iodado em humanos.(Universidade Federal de São Paulo (UNIFESP), 1991) Laranja, Sandra Maria Rodrigues [UNIFESP]; Schor, Nestor [UNIFESP]
- ItemAcesso aberto (Open Access)Avaliação da reprodutibilidade da tomografia computadorizada no estadiamento da pancreatite aguda(Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, 2007-12-01) Freire Filho, Edison de Oliveira [UNIFESP]; Shigueoka, David Carlos [UNIFESP]; Bekhor, Daniel [UNIFESP]; Vieira, Renata La Rocca [UNIFESP]; Yamada, André Fukunishi [UNIFESP]; Freire, Maxime Figueiredo de Oliveira [UNIFESP]; Ajzen, Sergio Aron [UNIFESP]; D'Ippolito, Giuseppe [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE: To evaluate the reproducibility of unenhanced and contrast-enhanced computed tomography in the assessment of patients with acute pancreatitis. MATERIALS AND METHODS: Fifty-one unenhanced and contrast-enhanced abdominal computed tomography studies of patients with acute pancreatitis were blindly reviewed by two radiologists (observers 1 and 2). The morphological index was separately calculated for unenhanced and contrast-enhanced computed tomography and the disease severity index was established. Intraobserver and interobserver reproducibility of computed tomography was measured by means of the kappa index (kappa). RESULTS: Interobserver agreement was kappa = 0.666, 0.705, 0.648, 0.547 and 0.631, respectively for unenhanced and contrast-enhanced morphological index, presence of pancreatic necrosis, pancreatic necrosis extension, and disease severity index. Intraobserver agreement (observers 1 and 2, respectively) was kappa = 0.796 and 0.732 for unenhanced morphological index; kappa = 0.725 and 0.802 for contrast-enhanced morphological index; kappa = 0.674 and 0.849 for presence of pancreatic necrosis; kappa = 0.606 and 0.770 for pancreatic necrosis extension; and kappa = 0.801 and 0.687 for disease severity index at computed tomography. CONCLUSION: Computed tomography for determination of morphological index and disease severity index in the staging of acute pancreatitis is a quite reproducible method. The absence of contrast-enhancement does not affect the computed tomography morphological index reproducibility.
- ItemAcesso aberto (Open Access)Contraste de baixa osmolaridade em ratos com lesão renal aguda por isquemia-reperfusão(Universidade Federal de São Paulo, 2023-10-10) Oliveira, Iris Gabriela Piazentin de [UNIFESP]; Fonseca, Cassiane Dezoti [UNIFESP]; Barbosa, Dulce Aparecida [UNIFESP]; lattes.cnpq.br/1924137485244907; lattes.cnpq.br/0639643818813583; lattes.cnpq.br/0238457221023652Fundamento: A nefropatia induzida por contraste (NIC) é responsável pela terceira causa de lesão renal aguda (LRA) adquirida por pacientes em meio hospitalar, sendo de maior risco em pacientes que já apresentam uma lesão renal incipiente. Deste modo, a osmolaridade do contraste iodado é significante, principalmente, quando a LRA é um fator de risco. Objetivo: Avaliar o efeito do contraste iodado de baixa osmolaridade com o fator de risco isquemia-reperfusão, por meio do modelo experimental animal. Metodologia: Foram utilizados 20 ratos da raça Wistar, machos e adultos, pesando entre 250-290g randomizados nos seguintes grupos experimentais. a) SHAM (n = 05): Animais utilizados para simulação do ato cirúrgico, sem clampeamento dos pedículos renais; b) Isquemia (n = 05): Animais utilizados para clampeamento dos pedículos renais por um período de 30 minutos; c) SHAM + Contraste Iodado (CI) (n = 05): animais SHAM que receberam 6ml/Kg de CI de baixa osmolaridade, via intraperitoneal, dose única; d) Isquemia + Contraste Iodado (n= 05): animais Isquemia que receberam 6ml/Kg de CI de baixa osmolaridade via intraperitoneal, dose única. Parâmetros fisiológicos como peso, ingestão de água e ração, razão entre o peso do rim e o do animal, função renal (clearance de creatinina) e perfil oxidativo (peróxidos e TBARS urinários) foram avaliados e seus resultados foram expressos em média ± desvio padrão. A variância entre os grupos foi analisada por meio do teste One Way ANOVA, seguida do pós-teste de comparações múltiplas de Newman-Keuls do programa estatístico Graph-Pad Prism version-3 for Windows®. Foram considerados significativos, valores de p < 0,05. Resultados: O grupo de animais Isq+CI sofreu mais com os efeitos do CI, comprovado pelo: menor clearance de creatinina, comparado ao grupo controle e isquemia; maior relação do peso rim/peso animal comparado ao grupo Sham+CI; maior estresse oxidativo, demonstrado pelo maior TBARS em relação aos grupos Sham+CI e Sham e maior FOX-2 quando comparado aos demais grupos (p<0,05). Conclusão: O CI de baixa osmolaridade resultou em nefrotoxicidade no modelo de fator de risco experimental de isquemia-reperfusão.
- ItemAcesso aberto (Open Access)Diagnosis of hepatic steatosis by contrast-enhanced abdominal computed tomography(Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, 2013-06-01) Monjardim, Rodrigo da Fonseca; Costa, Danilo Manuel Cerqueira; Romano, Ricardo Francisco Tavares; Salvadori, Priscila Silveira; Santos, Jaime de Vargas Conde dos; Atzingen, Augusto Castelli von [UNIFESP]; Shigueoka, David Carlos [UNIFESP]; D'Ippolito, Giuseppe [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective To evaluate the diagnostic capacity of abdominal computed tomography in the assessment of hepatic steatosis using the portal phase with a simplified calculation method as compared with the non-contrast-enhanced phase. Materials and Methods In the present study, 150 patients were retrospectively evaluated by means of non-contrast-enhanced and contrast-enhanced computed tomography. One hundred patients had hepatic steatosis and 50 were control subjects. For the diagnosis of hepatic steatosis in the portal phase, the authors considered a result of < 104 HU calculated by the formula [L - 0.3 × (0.75 × P + 0.25 × A)] / 0.7, where L, P and A represent the attenuation of the liver, of the main portal vein and abdominal aorta, respectively. Sensitivity, specificity, positive and negative predictive values were calculated, using non-contrast-enhanced computed tomography as the reference standard. Results The simplified calculation method with portal phase for the diagnosis of hepatic steatosis showed 100% sensitivity, 36% specificity, negative predictive value of 100% and positive predictive value of 75.8%. The rate of false positive results was 64%. False negative results were not observed. Conclusion The portal phase presents an excellent sensitivity in the diagnosis of hepatic steatosis, as compared with the non-contrast-enhanced phase of abdominal computed tomography. However, the method has low specificity.
- ItemAcesso aberto (Open Access)Enterografia por tomografia computadorizada: uma avaliação de diferentes contrastes orais neutros(Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, 2012-06-01) D'Ippolito, Giuseppe [UNIFESP]; Braga, Fernanda Angeli [UNIFESP]; Resende, Marcelo Cardoso [UNIFESP]; Bretas, Elisa Almeida Sathler [UNIFESP]; Nunes, Thiago Franchi [UNIFESP]; Rosas, George de Queiroz [UNIFESP]; Tiferes, Dario Ariel [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE: The purpose of this study was to assess the performance of neutral oral contrast agents, comparing intestinal distention, distinction of intestinal wall, acceptance and side effects. MATERIALS AND METHODS: Prospective, randomized, and double-blinded study involving 30 patients who underwent computed tomography of abdomen and pelvis with administration of neutral oral contrast agents, divided into three groups according the contrast agent type: milk, water, and polyethylene glycol. The images were consensually analyzed by two observers, considering the degree of bowel distention and intestinal wall distinction. The patients responded to a questionnaire regarding the taste of the ingested solution and on their side effects. Kruskal-Wallis and chi-square tests were employed for statistical analysis. RESULTS: Among 40 studied intestinal segments, appropriate bowel distension (intestinal loop diameter > 2 cm) was observed in 14 segments (35%) in the milk group, 10 segments (25%) in the water group and 23 segments (57%) in the polyethylene glycol group (p = 0.01). Preparation with polyethylene glycol resulted in the best bowel distention, but it presented the worst taste and highest incidence of diarrhea as reported by patients. CONCLUSION: Bowel preparation with oral polyethylene glycol results in higher degree of bowel distention than with water or milk, but presents worst acceptance related to its taste and frequency of diarrhea as a side effect.
- ItemSomente MetadadadosNefrotoxicidade do contraste radiológico em cultura de células mensangiais: avaliação hormonal e do cálcio intracelular.(Universidade Federal de São Paulo (UNIFESP), 1996) Laranja, Sandra Maria Rodrigues [UNIFESP]; Schor, Nestor [UNIFESP]
- ItemAcesso aberto (Open Access)Papel da ranitidina como meio de aprimorar a qualidade do exame de colangiopancreatografia por ressonância magnética(Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, 2013-04-01) Torres, Lucas Rios [UNIFESP]; Bretas, Elisa Almeida Sathler [UNIFESP]; Sauaia Filho, Galvani Ascar [UNIFESP]; Soares, Adriano Fleury de Faria [UNIFESP]; D'Ippolito, Giuseppe [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE: To assess the impact of oral ranitidine on the imaging quality in magnetic resonance cholangiopancreatography (MRCP). MATERIALS AND METHODS: Thirty-two patients underwent MRCP with 3D and 2D acquisitions, and three strategies for suppression of the gastrointestinal fluid signal: a) only at fasting; b) 12 hours after ingestion of 300 mg ranitidine; c) after oral administration of gadolinium solution. Three observers reviewed the images with a focus on the degree of visualization of the biliopancreatic tree. The interobserver agreement was evaluated with the kappa test. The difference between techniques and acquisition modalities were evaluated by means of average grading scores. RESULTS: The three strategies for suppression of the gastrointestinal fluid signal presented high reproducibility. The results with suppression of the gastrointestinal fluid signal with ranitidine where similar to those obtained with fasting, and both were worse than those obtained with gadolinium solution. The 3D acquisitions surpassed 2D only in terms of visibility of the cystic duct and gallbladder, and were inferior or equivalent in the other biliopancreatic ductal segments. CONCLUSION: The use of ranitidine does not seem justified in the evaluation of the biliopancreatic tree at MRCP, since 2D MRCP with fasting allows the visualization of ductal structures with high quality and reproducibility in the majority of cases.
- ItemAcesso aberto (Open Access)Perfusão por tomografia computadorizada do abdome: aplicações clínicas, princípios e técnica do exame(Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, 2012-02-01) Sousa, João Paulo Lira Barros Almeida de [UNIFESP]; Bekhor, Daniel [UNIFESP]; Saito Filho, Celso Fernando [UNIFESP]; Bretas, Elisa Almeida Sathler [UNIFESP]; D'Ippolito, Giuseppe [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)New imaging techniques have been developed with the objective of obtaining not only a structural assessment, but also a metabolic and functional analysis of different organs and types of lesions. Among such tools perfusion computed tomography (PCT) has recently aroused the interest of many researchers in studying the applicability of such imaging modality in the evaluation of abdominal organs and diseases. Analysis of the biological behavior of healthy and diseased tissues, differentiation of inflammatory processes from tumors, and diagnosis of tumor recurrence after minimally invasive therapies can be mentioned as applications of such an imaging modality. The main features of PCT are related to its ability to characterize different perfusional behaviors reflecting biological changes of certain lesions and diseased tissues. Thus, the present study was aimed at carrying out a comprehensive literature review, describing the key techniques and protocols utilized in PCT imaging, main clinical applications, advantages and disadvantages of the method, besides proposing an imaging protocol that can be adopted by both private and public health services, with good reproducibility and easy implementation.
- ItemSomente MetadadadosO valor da sedação e da bomba peristáltica elétrica para a infusão dos meios de contraste no tempo de realização da enteroclise bifásica com carboximetilcelulose a 0, 5 (por cento): análise de 55 casos(Universidade Federal de São Paulo (UNIFESP), 1995) Oliveira, José Marcelo Amatuzzi de [UNIFESP]