Abnormality of N30 somatosensory evoked potentials in Parkinson's disease: a multidisciplinary approach.

PURPOSE OF THE STUDY: Assess the N30 component of median nerve somatosensory evoked potentials (SEPs) in patients with Parkinson's disease (PD) and correlate its parameters with the severity of the disease, general cognitive ability and regional cerebral blood flow (rCBF). PATIENTS AND METHODS: Twenty-three non-demented, non-depressed PD patients (at stage II and III of the disease) and 23 age- and education-matched normal controls were enrolled in the study. SEPs were elicited by median nerve stimulation. PD patients' cognitive ability was assessed by means of: 1) Raven's Colored Progressive Matrices (RCPM); 2) the Test of Non-Verbal Intelligence (TONI-2); and 3) the Wisconsin Card Sorting Test (WCST). The patients' rCBF was evaluated by HMPAO SPECT. RESULTS: There was no difference between SEP N30 latency in PD patients and controls (P > 0.05). The P20-N30 peak-to-peak amplitude was lower in PD patients bilaterally (P < 0.05), and the amplitude of N30-P40 was lower on the right side only (P < 0.05). A significant increase in the amplitude ratio P14-N20/P20-N30 was observed in PD patients (P < 0.05). The correlation of these findings with the clinical parameters of the disease, and notably motor signs, was not significant. Of the three neuropsychological tests only the RCPM showed a positive relation to right P20-N30 amplitude. Regression analysis between SEP parameters and rCBF showed a correlation of N30 amplitude with blood flow in parietal cortical areas, but not in frontal regions.

Screening for minor changes in the distal part of the human dystrophin gene in Greek DMD/BMD patients.

The distal part of the human dystrophin gene is characterised by particular features and seems to play an important functional role. Additionally in recent years several data have implicated minor mutations in this gene region in some patients with mental retardation (MR). In order to screen for pathogenic mutations at the distal part of the human dystrophin gene we have used single-strand conformation analysis of products amplified by polymerase chain reaction (PCR-SSCA) in 35 unrelated male Greek DMD/BMD patients with no detectable deletions. Seven patients also had severe mental retardation. Direct sequencing of samples demonstrating a shift of SSCA mobility revealed six different and pathogenic minor changes, five in DMD and one in a BMD patient. Four of the mutations were found in DMD patients with severe MR. Three of these mutations were localised in exon 66, which presents an interesting similarity with part of the 3' end of the genome of eastern equine encephalomyelitis virus (EEEV). The present data from Greek DMD/BMD patients give further information about the phenotypic effects consequent on mutations in exons at the distal part of the human dystrophin gene.

Marinesco Sjögren syndrome with rhabdomyolysis. A new subtype of the disease.

Four children from two families with characteristics of Marinesco-Sjögren syndrome (congenital cataract, ataxia) are presented. All children had clinical and neurophysiological signs of a demyelinating polyneuropathy. Three of them developed acute rhabdomyolysis with marked weakness and CK levels of up to 40,000 U/I following a viral infection. In all children CK levels returned to normal within two weeks. Symptoms were recurrent in one of the children and resulted in a severe disability. In two other children recovery of motor function took about a month following the first attack. Metabolic disorders of the muscle were excluded by pathobiochemical examination of a muscle biopsy in one of the children. In conclusion, acute rhabdomyolysis can occur as a neuromuscular complication of Marinesco-Sjögren syndrome.

Hashimoto's encephalopathy: clinical and laboratory findings.

We describe a patient with a clinical picture characterized by subacute onset of confusion, myoclonus, tremor and generalized convulsive seizures with a relapsing course, which was attributed to Hashimoto's encephalopathy. EEG and MRI were diffusely abnormal. High titers of antithyroid antibodies were detected in her serum. She responded well to corticosteroids and her condition remained good during a one-year follow-up.