RESUMO
Irreversible electroporation (IRE) is a novel therapy that has shown to be a feasible and promising alternative to conventional ablative techniques when treating tumors near vital structures or blood vessels. The clinical efficacy of IRE has been evaluated using established imaging criteria. This study evaluates the histologic and imaging response of hepatic and pancreatic malignancies that were surgically resected after IRE. In total, 12 lesions ablated with IRE were included, including 3 pancreatic carcinomas, 5 primary tumors of the liver, and 4 metastatic tumors of the liver. The rate of complete response to IRE was 25% based on the histologic evaluation of the resected tumors. Although treatment-related vessel wall changes were noted in several cases in histologic findings, there was no evidence of vascular luminal narrowing or obliteration in any of the specimens. The imaging response to IRE before surgical resection usually resulted in underestimation of disease burden when compared with the histologic response seen on the resected specimens.
Assuntos
Técnicas de Ablação , Eletroporação/métodos , Neoplasias Hepáticas/cirurgia , Neoplasias Pancreáticas/cirurgia , Cirurgia Assistida por Computador/métodos , Técnicas de Ablação/efeitos adversos , Técnicas de Ablação/instrumentação , Idoso , Biópsia , Morte Celular , Bases de Dados Factuais , Eletroporação/instrumentação , Desenho de Equipamento , Feminino , Hepatectomia , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Tomografia por Emissão de Pósitrons , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Cirurgia Assistida por Computador/efeitos adversos , Cirurgia Assistida por Computador/instrumentação , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Carga TumoralRESUMO
Filamentous inclusions composed of the microtubule-associated protein tau are found in Alzheimer disease and other tauopathic neurodegenerative diseases, but the mechanisms underlying their formation from full-length protein monomer under physiological conditions are unclear. To address this issue, the fibrillization of recombinant full-length four-repeat human tau was examined in vitro as a function of time and submicromolar tau concentrations using electron microscopy assay methods and a small-molecule inducer of aggregation, thiazine red. Data were then fit to a simple homogeneous nucleation model with rate constant constraints established from filament dissociation rate, critical concentration, and mass-per-unit length measurements. The model was then tested by comparing the predicted time-dependent evolution of length distributions to experimental data. Results indicated that once assembly-competent conformations were attained, the rate-limiting step in the fibrillization pathway was tau dimer formation. Filament elongation then proceeded by addition of tau monomers to nascent filament ends. Filaments isolated at reaction plateau contained approximately 2 tau protomers/beta-strand spacing on the basis of mass-per-unit length measurements. The model suggests four key steps in the aggregation pathway that must be surmounted for tau filaments to form in disease.
Assuntos
Proteínas tau/química , Biofísica/métodos , Dimerização , Humanos , Cinética , Microtúbulos/química , Modelos Biológicos , Modelos Químicos , Modelos Estatísticos , Distribuição Normal , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Temperatura , Tiazinas/farmacologia , Fatores de TempoRESUMO
We present the case of a 15-year-old male with sporadic Burkitt's lymphoma/leukemia. The patient presented with right lower quadrant abdominal pain and masses in the terminal ilium and pelvis, and was subsequently demonstrated to have involvement of the bone marrow. We discuss differential diagnoses and approach to diagnose and stage this disease. A review of the clinical, radiologic, and pathologic features of Burkitt's lymphoma/leukemia are also presented.
