The clinical differential diagnosis of dementia: concept and methodology.

Dementia is a rather heterogeneous syndrome. This heterogeneity is expressed in the diversity of its clinical characteristics and its evolution and in the underlying etiologic factors. Unfortunately, these divisions do not run in parallel.

Does pupillary sparing oculomotor nerve palsy really spare the pupil?

We examined the pupillary cycle time (PCT) in eight elderly patients with isolated oculomotor nerve palsy (ONP) that was characterized by complete involvement of the extraocular muscles. In addition to advanced age, all patients had at least one other vasculopathic risk factor. Although in all cases the pupil was completely spared by clinical impression, the PCT was significantly prolonged compared with the other eye and well outside the normal range (mean 1590 +/- 212 msec on the involved side and 1076 +/- 110 on the uninvolved side).

EEG and topographic frequency analysis in common and classic migraine.

Electroencephalographic (EEG) changes occurring in patients with migraine have received much attention. However, almost equal number of reports indicate the predominance of normal and abnormal findings. We studied the EEG in symptom-free, otherwise healthy, unmedicated 18-28 year-old patients: 22 with common migraine, 20 with classic migraine, and 20 age-matched controls.

Carpal tunnel syndrome: a complication of idiopathic torsion dystonia.

Carpal tunnel syndrome (CTS) is usually an idiopathic disorder. Certain occupations that require frequent flexion movements of the hand at the wrist are recognized as precipitating the development of CTS. Dystonia can cause similar excessive movements at the wrists.

The pupillary effects of retrobulbar injection of botulinum toxin A (oculinum) in albino rats.

Botulinum toxin (BoTx) has been clinically used in the treatment of localized dystonic states such as blepharospasm, as well as in strabismus. Reported side effects have included primary excessive weakness of neighboring extraocular muscles. To evaluate possible involvement of the iris, we injected BoTx into the retrobular space of albino rats.

Genetic and environmental factors determining the development of Creutzfeldt-Jakob disease in Libyan Jews.

The cluster of Creutzfeldt-Jakob disease (CJD) among Jews of Libyan origin is one of the largest in the world. A number of hypotheses have been proposed to account for this cluster, the most prevalent but unsubstantiated hypothesis being that a transmissible agent was ingested in the form of scrapie-infected sheep brains. It has, however, been shown that a modified host protein encoded by the gene specifying the scrapie amyloid precursor is critically involved in the pathogenesis of transmissible spongiform encephalopathies such as CJD, Gerstmann-Strüssler-Scheinker syndrome and Kuru.

A mutation in the prion protein gene in Creutzfeldt-Jakob disease in Jewish patients of Libyan, Greek, and Tunisian origin.

A modified host protein encoded by the gene specifying the scrapie amyloid precursor is critically involved in the pathogenesis of transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease (CJD), Gerstmann-Straussler-Scheinker's syndrome, and Kuru. A mutation in the open reading frame of this gene was recently described in a cluster of patients with CJD in Slovakia. This mutation at codon 200 changes glutamic acid coded by GAG to lysine coded by AAG.

Routine and quantitative EEG analysis in Gilles de la Tourette's syndrome.

Gilles de la Tourette's syndrome (GdlT) is a neurobehavioral disorder, with a reportedly high frequency of EEG abnormalities. We performed EEGs on 48 consecutive patients with GdlT, and frequency analysis in 26 patients (17 males), and compared the results with those from age- and sex-matched normal controls. Routine 18-channel EEG revealed minimal diffuse nonspecific slowing in only 3 of 48 patients (6%) and in 2 of 26 controls (7.

Dopaminergic drugs influence the intensity of catalepsy induced by microinjections of carbachol into the reticular formation.

Carbachol microinjections into the mesencephalic and pontine reticular formation in rats induced intense and long-lasting catalepsy. Systemically administered haloperidol potentiated, while apomorphine and L-DOPA reduced the cataleptogenic effect of carbachol. These results indicate the existence of functional relations between the cholinergic cataleptogenic mechanism in the reticular formation and the dopaminergic system.

Prediction of binaural click lateralization by brainstem auditory evoked potentials.

A previous study by Furst et al. (1985) has shown that in healthy subjects brainstem responses evoked by binaural auditory stimuli with interaural time difference (ITD) and interaural level difference (ILD) include information about the integration of data received by both ears. A correlation was found between the first major peak of the binaural difference waveform and perception of click lateralization and fusion.

Sympathomimetic amines and cardiac arrhythmias.

Study Objective: The aim was to investigate the arrhythmogenic properties of several sympathomimetic amines and their antagonism by adrenergic blocking drugs.

Design: Arrhythmia was induced by the investigated drugs, injected intravenously: adrenaline (ADR); noradrenaline (NA); phenylephrine (PE); isoprenaline (IP); terbutaline (Tb) and salbutamol (Sb). ADR and PE were also tested for their arrhythmogenic properties after the administration of the adrenergic antagonists propranolol, phentolamine, or both.

Rats immunized with cholinergic synaptosomes: a model for Lambert-Eaton syndrome.

Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disorder characterized by reduced acetylcholine release at the neuromuscular junction. We report a model of the disease developed by active immunization of rats with purely cholinergic nerve terminals (synaptosomes) isolated from the Torpedo electric organ. Electromyographic studies of neuromuscular transmission in these rats showed a weak initial response followed by a pronounced incremental response to paired supramaximal stimuli (8 msec apart).

EEG recordings following intrathecal iohexol administration.

Electroencephalogram (EEG) recordings were performed before and after intrathecal administration of iohexal (Omnipaque) in 30 patients who underwent cervical myelography or cisternography. Tracings were recorded before, several hours after, and 24 h after iohexol administration. No abnormalities were recorded.

Complex segregation analysis of dystonia pedigrees suggests autosomal dominant inheritance.

We reanalyzed data collected in a large family study of idiopathic torsion dystonia (ITD) using complex segregation analysis. Previous investigators concluded that the mode of inheritance of ITD differed between Jews and non-Jews. The results from our segregation analyses suggest that ITD is inherited as an autosomal dominant trait, with low penetrance (0.

Seizures of unknown origin after the age of 50: vascular risk factors.

To investigate the possible etiologic factors of late onset seizures of unknown origin, 50 consecutive patients whose seizures started after age 50 and who had a normal CT, were screened. The seizures in this group were generalized in 70% and infrequent. The hypothesis that late-onset seizures of unknown origin were frequently due to microinfarcts, was evaluated by comparing the frequency of arterial hypertension, coronary heart disease, peripheral vascular disease, carotid bruits, diabetes mellitus and smoking in these patients with appropriate control groups.

Effects of atropine on learning and memory functions in dementia.

The effect of intravenous atropine (1 mg) or saline on mnemonic function was tested in patients with various forms of dementia and age-matched controls. Examinees consisted of 12 subjects having Alzheimer's disease (AD), multi-infarct dementia (MID), Parkinson's disease without dementia or with dementia, and normal aged controls. Wechsler's adult memory scale was used.