Peripheral markers of the gamma-aminobutyric acid (GABA)ergic system in Angelman's syndrome.

It has recently been demonstrated that patients with Angelman's syndrome who exhibited a deletion on cytogenetic tests show more severe clinical pictures with drug-resistant epilepsy than patients with Angelman's syndrome not carrying the deletion. To verify if this difference in clinical severity can be attributed to genes for the three gamma-aminobutyric acid (GABA)A receptor subunits (GABRB3, GABRA5, GABRG3) located in the deleted region, a possible modification of peripheral markers of the GABAergic system was investigated in 12 subjects with Angelman's syndrome and 20 age-matched subjects (8 with idiopathic epilepsy and 12 not affected by neurologic diseases). The results confirmed a more severe clinical picture, and epilepsy syndrome in particular, in Angelman's syndrome patients with deletions versus patients without deletions. In contrast, biochemical study (based on dosage of plasma levels of GABA and diazepam binding inhibitor, an endogenous ligand of GABAA and peripheral benzodiazepine receptors, showed contradictory results: patients with Angelman's syndrome showed significantly higher levels of GABA and diazepam binding inhibitor than patients without neurologic impairment but significantly lower levels than epileptic controls.

Generic SoC QR Array Processor for Adaptive Beamforming

A generic architecture for implementing a QR array processor in silicon is presented. This improves on previous research by considerably simplifying the derivation of timing schedules for a QR system implemented as a folded linear array, where account has to be taken of processor cell latency and timing at the detailed circuit level. The architecture and scheduling derived have been used to create a generator for the rapid design of System-on-a-Chip (SoC) cores for QR decomposition. This is demonstrated through the design of a single-chip architecture for implementing an adaptive beamformer for radar applications. Published as IEEE Trans Circuits and Systems Part II, Analog and Digital Signal Processing, April 2003 NOT Express Briefs. Parts 1 and II of Journal reorganised since then into Regular Papers and Express briefs