Miniaturized one-chip electrochemical sensing device integrated with a dialysis membrane and double thin-layer flow channels for measuring blood samples.

We have developed a microfluidic device consisting of a gold film working electrode modified with lactate oxidase and Os-poly(vinylpyridine) mediator containing horseradish peroxide, and reference and counter electrodes in a microflow detection channel separated by a microdialysis membrane from another microflow channel used for sample injection. The dialysis membrane is cellulose with a molecular weight cut off of 10 kDa. We achieved control over a wide recovery rate range of 3-94% because the device is capable of controlling both flow rates in the dual thin-layer channels.

Ultrastructural changes of basal laminae and protoplasmic astrocytes in craniostenosis with epilepsy.

Human brain biopsy specimens from twenty-four patients with epilepsy associated with craniostenosis and characterized by electroencephalography, were studied with an electron microscope. Characteristic ultrastructural changes were found in the basal lamina covering capillaries in the gray matter where the basal lamina was partially thickened, split and transformed into a heterogeneous network of strand enclosing electron-lucent areas. In the gray matter associated with epileptic convulsions, numerous filaments 60-100 nm in diameter appeared in protoplasmic astrocyte endfeet, apparently inserting in the plasma membrane adjacent to the basal lamina.