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After Alzheimer's disease (AD), vascular dementia (VaD) is the most common cause of dementia among the elderly. Abnormalities in neurotransmitter pathways are common pathogenic mechanisms shared by AD and VaD. For one month we studied the effects of donepezil, an acetylcholinesterase inhibitor (5 mg daily), on the cognitive system using P300 auditory event-related potentials (P300) and neuropsychological tests in 10 patients affected by probable VaD according to the NINDS-AIREN criteria. Our data showed a significant improvement of neuropsychological items and P300 latency after one month of donepezil treatment. In conclusion both P300 and neuropsychological tests are indicated in patients with VaD to confirm the efficacy of donepezil treatment during follow-up.

Since January 2000 we have administered entacapone (200 mg) to 75 patients with severe Parkinson's disease in combination with their routine levodopa dose. At baseline the mean UPDRS (item III) score was 38+/-6. After 3 months of entacapone therapy the patients presented a significant improvement of motor fluctuations; the mean UPDRS score (item III) was 20+/-4. This improvement was also statistically significant after 2 years of entacapone therapy.

We describe three siblings from an Italian family affected by an autosomal recessive spinocerebellar degeneration. Gait ataxia, presenting between 38 and 45 years, was the first symptom in all three patients. Dysarthria, dysmetria, brisk tendon reflexes, extensor plantar response, and scoliosis were constant features. Disease progression was slow. Electrophysiologic studies demonstrated a slight reduction in sural nerve sensory action potential in only one patient. Analysis of GAA expansion within the X25 gene showed that patients were homozygous for the expansion, with the shorter expanded allele ranging from 120 to 156 triplets. The size of the GAA expansion may be smaller than we previously described. Such minimal expansions may result in atypical forms of Friedreich's ataxia.

Visual evoked potentials (VEPs) to pattern reversal vertical bar stimuli were recorded from 24 scalp derivations (including zygomatic and inion) referenced to digitally linked earlobes in 50 controls. 1, 2 and 4 cpd patterns were presented as full field (FF) stimuli, on Upper Hemifields (UHF) and Lower Hemifields (LHF), upper and lower quadrants and with the occlusion of central and peripheral UHF and LHF. VEPs to octant stimuli were also recorded with 2 cpd patterns. N1, P1 and N2 components were recorded from posterior and inion derivations with FF stimuli, from posterior derivations with LHF stimuli, only from inion leads with UHF stimuli, from derivations ipsilateral to stimuli with quadrants and octants, and consistently from midline derivations only with lower quadrants. Polarity inverted sequences (iN1-iP1-iN2) were recorded from the other scalp derivations, with similar latency and spatial frequency sensitivity as N1-P1-N2. Single Equivalent Dipole (ED) calculations were performed on N1 and P1 recorded in the different stimulus conditions. Our findings contradict previous hypotheses on VEP generators and contradict the predictions of VEPs polarity and distribution based on the "cruciform model" of VEPs generators. In order to explain the distribution of VEPs to upper and lower half fields and to quadrant and octants, we propose a model based on the position of the medial and occipito-polar surface of visual cortex in man.

Expert chess players can recall meaningful chess positions with extraordinary precision in comparison with inexperienced players. We hypothesized, therefore, that their mental performance during chess deliberation could be an appropriate target for single photon emission computerized tomography (SPECT) studies. We studied cerebral activation with 1110 MBq 99mTc-Bicisate SPECT in five expert male chess players during mental solution of a complex chess problem. Region of interest (ROI) analysis, in comparison with average weighted cerebellar counts, showed activation by 10% or more, of the non dominant prefrontal area (right in four dominant right handed players, left in one dominant left handed player) and by 2-6% in the non-dominant middle temporal areas. Maximum variability of ROI analysis versus cerebellar counts in test/retest evaluation is in our laboratory, as in others, 1.5%. Our results are in agreement with neuropsychological studies suggesting that the non-dominant hemisphere is specialized for chess skill, and show that non-dominant prefrontal and temporal lobe activation during chess deliberation can be detected by SPECT.

We recorded short latency somatosensory evoked potentials (SEPs) to median nerve stimuli in 40 patients affected by idiopathic Parkinson's disease (PD) classified from I to IV on the Hoehn and Yahr disability scale. SEPs were recorded before and after chronic administration of L-Dopa and bromocriptine, before and after acute administration of L-Dopa. Fourteen patients experiencing wearing off and dystonic-dyskinetic disturbances were recorded during the occurrence of these oscillations of their clinical status. Absent or reduced N30 components were found in 32.5% of patients. SEPs were not modified by acute or chronic administration of L-Dopa or bromocriptine or during off and dystonic or dyskinetic conditions. Multiple correlations of N30 with scores of the Unified Parkinson's Disease Rating Scale showed that N30 abnormality did not classify patients with prominent clinical features, nor did it predict the outcome of treatment.

Narcolepsy and cataplexy began one year before treatment of a left mid-temporal primary B-cells lymphoma in a HLA DR2 negative man. Treatment with radio therapy and immunosuppression induced regression of the lymphoma and disappearance of narcolepsy and cataplexy.

We described the clinical, electrophysiological (electromyography, sensory and motor nerve conduction study, somatosensory evoked potentials, brainstem auditory evoked potentials, visual evoked potentials) and neuroradiological (brain magnetic resonance) data in 3 siblings (2 males and 1 female, age range: 54-48 years) affected by autosomal recessive late onset cerebellar ataxia. The 3 patients showed at the electrophysiological examination: mild peripheral neuropathy, involvement of somatosensory pathways both on central and peripheral side. A mild cerebellar atrophy, most evident in the female more severely disabled, was found by magnetic resonance.

Delayed P3 ERPs were recorded with an acoustic oddball paradigm in 5 patients affected by unilateral thalamic hemorrhage. P3 latencies in these 5 patients were above the normal mean latency of age-matched controls +2/+3 S.D.s. The P3 delay was persistent in serial follow-ups at 6 months from stroke. Normal P3 latencies were instead recorded in 4 patients with paramedian hemorrhage not involving or only partially involving the thalamus.

We studied 10 patients with post-traumatic amnesia (PTA) and normal CTscans. P3 with an oddball paradigm, several neuropsychological tests and EEG were performed the day after the trauma and several times later until full recovery. In all patients, P3 latencies at admission were above normal limits (mean + 2 SDs) and decreased progressively during recovery from PTA. The latency reductions correlated significantly with improvement of neuropsychological tests.

Bit mapped color imaging of SEPs was recorded from 19 derivations in 11 healthy volunteers after electrical stimulation of the median nerve at the wrist, index finger digital nerve stimulation, and mechanical stimulation of the index fingertips by an electromechanically driven vibrating thin metallic plate. The latencies of SEP components increased for the various stimulation modalities, being shortest after median nerve stimulation at the wrist and longest after mechanical stimulation of the index fingertips. The scalp distribution of SEPs to mechanical stimuli was, however, the same as other SEPs, independently of the stimulation employed, and components corresponding to N20 and P22 were recorded only contralaterally to the stimulated side.

Ten patients with myotonic dystrophy have been studied by M-mode and 2-dimensional echocardiography. Six patients had echocardiographic abnormalities: mitral valve prolapse, hypertrophy of the papillary muscles (2 cases); impaired regional left ventricular relaxation, probably due to "cardiac myotonia" (4 patients); and dilatative cardiomyopathy in the sole patient with overt heart disease. There seems to be no relation between involvement of skeletal and cardiac muscle. It is likely, although not proved, that myocardial involvement in myotonic dystrophy occur initially as "myotonia", followed by a "dystrophic" phase with severe dilatative cardiomyopathy, not unlike the skeletal muscle.

Placentae or uteri from pregnant rats (days 12-21) contained no detectable alpha-subunit of the glycoprotein hormones (CG, TSH, FSH, and LH) when assayed in either a rat or human alpha-RIA. The heads of rat fetuses contained increasing concentrations of alpha-subunit when assayed from days 12-20 of gestation (7.2-46 ng/g). Human term placenta contained large quantities of alpha-subunit (16,000 ng/g). alpha-Subunit was synthesized by the cell-free translation of poly(A)-enriched mRNA from mouse TSH-secreting pituitary tumor and human term placenta, but not from rat placentae or uterine implantation sites (days 11-21 of gestation). In addition, alpha mRNA was detected in mouse TSH-secreting pituitary tumor, rat pituitary, and human term placenta by hybridization to a 32P-labeled mouse alpha cDNA probe although no alpha mRNA could be detected in rat placentae (days 13-21 of gestation). The luteotropic activity found in pregnant rodents must be caused by a substance with a structure substantially distinct from any known gonadotropin.