Bonanni L.,University of Chieti Pescara |
Onofrj V.,University of Milan |
Scorrano V.,Neurofisiopatologia |
Onofrj M.,University of Chieti Pescara |
Thomas A.,University of Chieti Pescara
Open Neurology Journal | Year: 2010
We present two further cases of the pharyngeal-cervical-brachial (PCB) form of GBS, with unfavourable outcome, showing dramatic dissociation between upper and lower body Symptoms. Both patients showed rapidly progressive motor denervation with disappearance of Compound Muscle Action Potentials (CMAPs) in upper limbs muscles. Sensory Nerve Action Potentials (SNAPs) were instead normal. Normal reflexes, F waves and action potentials were elicited in lower limbs. Despite i.v. Immunoglobulin treatment no recovery was observed and both patients died within a year from onset of symptoms.
Stefani A.,Neurofisiopatologia |
Stefani A.,University of Rome Tor Vergata |
Fedele E.,University of Genoa |
Vitek J.,University of Minnesota |
And 11 more authors.
Cell Death and Disease | Year: 2011
At odd with traditional views, effective sub-thalamic nucleus (STN) deep brain stimulation (DBS), in Parkinson's disease (PD) patients, may increase the discharge rate of the substantia nigra pars reticulata and the internal globus pallidus (GPi), in combination with increased cyclic guanosine monophosphate (cGMP) levels. How these changes affect the basal ganglia (BG) output to the motor thalamus, the crucial structure conveying motor information to cortex, is critical. Here, we determined the extracellular GABA concentration in the ventral anterior nucleus (VA) during the first delivery of STN-DBS (n=10) or following levodopa (LD) (n=8). Both DBS and subdyskinetic LD reversibly reduced (-30%) VA GABA levels. A significant correlation occurred between clinical score and GABA concentration. By contrast, only STN-DBS increased GPi cGMP levels. Hence, STNON and MED-ON involve partially different action mechanisms but share a common target in the VA. These findings suggest that the standard BG circuitry, in PD, needs revision as relief from akinesia may take place, during DBS, even in absence of reduced GPi excitability. However, clinical amelioration requires fast change of thalamic GABA, confirming, in line with the old model, that VA is the core player in determining thalamo-cortical transmission. © 2011 Macmillan Publishers Limited All rights reserved.