RESUMO
The particle-induced X-ray emission (PIXE) method and the 14N(d,p)15N nuclear reaction are combined for simultaneous trace element and nitrogen determination. Measurement of nitrogen content often allows the relating of the elemental concentrations determined by PIXE to the protein content of the sample. For the measurements only a small amount of sample material is needed; therefore, it is possible to keep track of the quantity of a certain element in the successive steps of a biomedical separation process. In about 10 min, trace element concentrations in the ppm range can be determined with a statistical accuracy of about 10%.
Assuntos
Elementos Químicos/análise , Tetróxido de Ósmio , Proteínas/análise , Compostos de Zinco , Cianobactérias/enzimologia , Cabelo/análise , Humanos , Matemática , Microquímica , Nitrogênio/análise , Osmio/análise , Prótons , Teoria Quântica , Espectrometria por Raios X , Coloração e Rotulagem , Superóxido Dismutase/análise , Zinco/análiseRESUMO
Synaptic junctional fractions were separated from rabbit brain by procedures based on combining the methods of Cotman and Taylor [4], Orosz et al. [16, 17] and Lisman et al. [13]. Thin layers of cerebral cortices were homogenized to obtain a crude mitochondrial-synaptosomal fraction. The sedimentation rates of mitochondria and mitochondria containing synaptosomes were increased by raising the density of mitochondria with an insoluble dense formazan deposit inside mitochondria after iodo-nitrotetrazolium treatment. The synaptic plasma membrane fraction isolated by this method contained no mitochondrial contamination. After Triton X-100 treatment the insoluble residues of the detergent were centrifuged through discontinuous sucrose gradients. A great enrichment of morphologically identifiable intact synaptic junctions was observed in some of the obtained interface layers.
Assuntos
Córtex Cerebral/análise , Mitocôndrias/análise , Membranas Sinápticas/análise , Animais , Centrifugação Isopícnica/métodos , Córtex Cerebral/ultraestrutura , Detergentes , Mitocôndrias/ultraestrutura , Octoxinol , Polietilenoglicóis , Coelhos , Ensaio Radioligante , Membranas Sinápticas/ultraestruturaRESUMO
Proton induced X-ray emission analysis measurements were performed to determine the P, S, K, Ca Fe, Ni, Cu and Zn ion content of presynaptic vesicles prepared from guinea-pig brain cortex. The number of different ions per single vesicle is calculated using the results of the additional protein content determinations. The ion contents of cholinergic and adrenergic vesicles are compared.
