cover image European Journal of Neurology

European Journal of Neurology

1996 - Volume 3
Issue 4 | July 1996

Review

Abstract

The increasing knowledge concerning anatomical structures and cellular processes underlying event‐related potentials (ERP) and methodological advances in ERP data analysis (e.g. dipole source analysis) begins to bridge the gap between ERP and neurochemical aspects. Several recent reports are summarized suggesting that quite specific relationships may exist between certain ERP‐parameters and central cholinergic, noradrenergic and especially serotonergic function. Reliable indicators of the serotonin system are urgently needed because of its role in pathogenetic concepts and as target of pharmacotherapeutic interventions in psychiatric and neurologic disorders. Converging arguments from preclinical and clinical studies are presented supporting the hypothesis that the dependence of the auditory evoked N1/P2‐response on stimulus intensity (loudness) is regulated by the level of central serotonergic neurotransmission. Dipole source analysis represents an important methodological advance in this context, because N1/P2‐subcomponents, generated by different cortical structures with different serotonergic innervations, can be separated. A pronounced intensity dependence of the evoked activity of primary auditory cortices is supposed to indicate a low central serotonergic neurotransmission and vice versa. This intensity dependence is shown to be a parameter with clinical value because subgroups of patients with a serotonergic dysfunction can be identified and can be treated more specifically.

Original Article

Abstract

One hundred and eight patients with amyotrophic lateral sclerosis (ALS) received ceftriaxone 2 g daily i.v. (62) or i.m. (34) or by both routes (12), for 21‐day cycles on an open basis. Baseline MRC and Norris scores were similar to those at the end of the first 21‐day cycle of therapy. Seven patients showed remarkable clinical improvement, mostly segmental, which started during the first week of treatment and lasted up to 2 months after its completion. Improvement was also noted in seven out of 21 cases given a subsequent cycle of treatment. Based on these findings, the drug is supposed to act by altering the neurochemical transmission at the neuromuscular junction and/or by facilitating the presynaptic uptake of glutamate at the synaptic junction. This hypothesis positively correlates with the results of experiments showing that ceftriaxone increases H‐glutamate uptake in rat spinal cord synaptosomes.

Original Article

Abstract

The concept of vascular dementia remains controversial. Indeed, in many instances what is called vascular dementia may neither be vascular nor dementia. However, while overdiagnosis may be frequently made, underrecognition of vascular factors in dementia also seems common. Recent works show that focal/multifocal cognitive and executive dysfunction which may follow sequential or more rarely single‐strategic stroke should be differentiated from more diffuse progressive intellectual decline mimicking a degenerative disorder (such as Alzheimer's disease) which may smoothly develop in over one fourth of stroke patients.

Original Article

Abstract

Multiple sclerosis (MS) is a chronic inflammatory disease characterized by focal demyelination of central nervous system (CNS). Susceptibility to MS is thought to be affected by multiple genes including HLA and T cell receptor (TCR) genes. In view of the recent evidence, that in addition to α/β T lymphocytes also γ/δ T cells may have autoreactive potential, TCR delta repertoire in peripheral blood of MS patients has been studied. TCR delta repertoire, as assessed by Vδ‐Jδ rearrangements, has been analysed in 13 MS cases and in 30 healthy individuals by seminested PCR technique. Oligonucleotide primers specific for six Vδ regions and for Jδ1 gene were used for amplification of Vδ‐Jδ junctional region responsible for the diversity of γ/δ TCR. In the majority of MS patients PAGE analysis of Vδ1‐Jδ1, Vδ3‐Jδ1 and Vδ5‐Jδ1 rearrangements showed single‐band or two‐band pattern. The most striking result has been observed in Vδ5‐Jδ1 rearrangement, where in nine cases studied single band and in four patients two bands have been found. In all but one MS cases multi‐band pattern of Vδ2‐Jδ1 rearrangement was obtained. None of the 13 MS patients showed single‐band rearrangement pattern of Vδ4‐Jδ1 and Vδ6‐Jδl. Contrary to the MS group almost all healthy individuals produced smear‐like or multi‐band pattern of Vδ1‐Vδ5 to Jδ1 rearrangements. On the basis of the banding pattern produced by Vδ‐Jδ rearrangement in MS, it can be suggested that T lymphocytes had undergone clonal expansion , most likely due to stimulation by antigen related to CNS. In particular a very consistent single‐band pattern of Vδ5‐Jδ1 rearrangement observed in almost all MS patients studied, argues very strongly for a significant role of γ/δ T cells with Vδ5 rearrangement in the pathogenesis of MS. However, it cannot be excluded that the observed patterns of TCR δ gene rearrangement in MS patients may represent secondary changes to CNS damage.

Original Article

Abstract

Human herpes virus 6 (HHV‐6) is a new member of the herpes virus family, able to remain integrated in the human genome after primary infection and to transactivate the expression of retroviral genes. It has been recognized to be lymphotropic and neurotropic, although its possible role in neurological diseases is largely unknown. Up to now HHV‐6 infection has been studied mainly in inflammatory and disimmune diseases of the central nervous system. Taking into account the viral theories on the origin of amyotrophic lateral sclerosis (ALS) and the biological properties of HHV‐6, we investigated the presence of viral specific sequences in the total DNA extracted from the peripheral blood mononuclear cells (PBMCs) from 20 ALS patients as well as from 20 blood donors by PCR. The results showed the absence of HHV‐6 specific sequences in the DNA of ALS patients as well as of controls. Nevertheless, before conclusions can be drawn on the possible role of HHV‐6 as cofactor in the development of ALS, it is necessary to examine cells other than lymphocytes and a larger number of subjects.

Original Article

Abstract

Anti‐Hu antibodies are usually present in patients with paraneoplastic encephalomyelitis/sensory neuropathy (PEM/SN), and anti‐Hu IgG is found in the nucleus of neurons in the autopsy of these patients. To investigate the clinical effect and distribution of anti‐Hu IgG in the nervous system in an experimental animal model, we injected intraperitoneally anti‐Hu IgG from five patients with PEM/SN to mice daily for 1 or 2 weeks. The IgG distribution in the nervous system was analyzed by an avidin‐biotin immunoperoxidase technique in animals sacrificed 24 h after the last injection. In one group of mice the nervous system was fixed by perfusion and in another (autopsy group) by immersion after keeping the dead animal 16 h at 4°C. None of the mice showed clinical or pathological abnormalities. IgG immunoreactivity was similar in the nervous system of mice injected with anti‐Hu or control IgG. In the perfusion‐fixed mice, IgG was present in leptomeninges, choroid plexus and extracellular space of Gasserian and dorsal root ganglia (DRG). In the autopsy group, there was IgG immunoreactivity in the cytoplasm of neurons of many areas of the brain and in more than 90% of neurons of DRG. Neuronal nuclear IgG deposits were only rarely observed. We conclude that anti‐Hu antibodies alone probably are not responsible for the PEM/SN syndrome. IgG diffusion into the cytoplasm of neurons is a post‐mortem artifact, but this model did not reproduce the predominant nuclear IgG staining observed in autopsies from PEM/SN patients.

Original Article

Abstract

We prospectively studied 160 patients (18–47 years of age) with TIA (18) or ischemic stroke (142). Eighty‐five subjects were under the age of 40. All patients underwent noninvasive ultrasound studies (transcranial doppler and echocardiography), plus a battery of laboratory studies including coagulation and antibodies tests and blood lactate‐pyruvate. Angiographic studies were performed in 42% of patients (33% with DSA and 9% with MRA). The most common etiologies were found to be cardioembolic (more common in the 18–39 age group) and atherothromboticic (more common in the 40–47 age group). Autoimmune conditions affected 12.5% of patients, while arterial dissections affected 11%. In 10% of patients the etiology of the cerebral ischemic event could not be determined, in spite of an extensive and expensive workout Hence, a set of guidelines aimed at optimizing, in terms of cost‐benefit, a protocol of investigations in young adults with ischemic stroke is tentatively proposed.

Original Article

Abstract

Lipoprotein (a) [Lp (a)] is a cholesterol‐rich lipoprotein that structurally resembles the low density lipoprotein cholesterol (LDL‐C) particles, but contains a molecule of apolipoprotein (a) attached to apolipoprotein B by disulfide bond. Because of the fact that high plasma levels of Lp (a) have been shown to be associated with cerebrovascular disease (CVD), we determined plasma Lp (a) levels in CVD for the Turkish population, and compared them with previous findings of some developed countries. Plasma Lp (a) levels were evaluated in CVD and control groups. The mean plasma Lp (a) levels in the CVD group was found to be approximately two‐fold higher than that of the control group (0.21 g/1 vs 0.38 g/1). Also, it was found to be higher than the mean levels of CVD group in the other populations described in previous reports. But CVD prevalence in the Turkish population is lower than in those of developed countries, especially United States and Japan. Therefore, we believe that each of those populations should determine their plasma Lp (a) levels to observe the risk for CVD.

Original Article

Abstract

Hippocampal memory dysfunction is a main symptom of mesiotemporal lobe epilepsy (TLE). It may increase after temporal lobectomy for seizure relief. The aim of this study was to assess the ability of psychometry during hippocampal electrical stimulation to predict post‐operative memory deficits and thereby to contribute to lateralization of the epileptogenic zone. A computerized memory test was performed during low intensity hippocampal stimulation in nine patients with TLE during invasive presurgical evaluation. The following results were obtained: speech dominant hippocampal stimulation induced subtle verbal memory deficits in patients with the epileptogenic zone in the speech dominant hemisphere and normal baseline memory performance. Verbal memory deficits could not be induced in patients with the epileptogenic zone in the speech dominant hemisphere and pre‐existing memory deficits, or if the seizure origin was contralateral to speech dominance. Thus it was possible to lateralize the epileptogenic zone in patients with normal baseline memory performance by revealing hippocampal dysfunction only during electrical stimulation. Post‐operative psychometric testing demonstrated that the individual risk for impairment of verbal memory performance following temporal lobectomy could be predicted correctly. In conclusion, psychometry during hippocampal stimulation may allow prediction of memory deficits following temporal lobectomy and improve determination of the epileptogenic zone.

Original Article

Abstract

Studies comparing non‐surgical patients with left or right temporal lobe epilepsy (TLE) have shown irregular differences in verbal learning and memory. We assessed the performance of unoperated patients with epileptogenic temporal lobe lesions or cryptogenic TLE using a selective reminding procedure for the learning of a word list, and five delayed trials for the recall of learned words. On the selective reminding procedure, patients with left TLE were found to be more impaired than those with right TLE and controls, in agreement with the role of the left temporal lobe in verbal learning. The patients with right TLE were more impaired than the controls, possibly due to the semantic organization of the word list The rate of forgetting learned words was similar in the patient and control groups, suggesting that patients with left TLE can normally retain and/or retrieve stored items. These data support the hypothesis that distinct functional systems subserve learning and memory. Comparisons of the patient subgroups with epileptogenic lesions (hippocampal sclerosis or low‐grade glioma) and those with cryptogenic TLE did not reveal any significant difference in learning or in memory, suggesting that epileptiform activity could affect verbal performance as a detectable temporal lesion.

Original Article

Abstract

Nineteen non‐demented Parkinson's disease patients have been studied before and during L‐dopa therapy by quantitative EEG performed at rest with eyes closed (EC) and during attentive (BR) and cognitive (FIX) tasks. The data have been compared by ANOVA analysis with those of 22 age‐matched healthy subjects. In all three conditions a significant increase of the mean δ power as well as a decrease of β1 power was observed in patients before therapy. Abnormal high δ values were observed in 10 out of 19 patients. L‐Dopa therapy did not modify this EEG pattern. After therapy, however, a significant decrease of reactivity to BR and FIX was observed in patients compared to normal subjects. These data confirmed the presence of an EEG synchronization (increase of slow activity and decrease of fast activity) in non‐demented Parkinson's disease patients. This pattern, similar to that of subjects with Alzheimer‐type dementia, might indicate an intellectual impairment at sub‐clinical level. A non‐dopaminergic mechanism could be responsible for this impairment

Original Article

Abstract

Human blood platelets are more and more regarded as a reliable model of nerve cells, and some biochemical alterations found in platelet enzyme activities and receptor binding parameters may be related to analogous changes occuring in the central nervous system. Platelet phenol‐sulphotransferase activity has been evaluated in some neurological disorders, such as Parkinson's disease and headache. In the present work we determined phenolsulphotransferase activity in platelets of 36 patients with dementia of Alzheimer type, and compared such activity values with those of 36 sex‐ and age‐matched healthy controls. Patients showed a significantly higher platelet phenolsulphotransferase activity than control subjects, both with dopamine and with phenol as substrates. Moreover, a significant positive correlation was found between platelet enzyme activity and severity of illness. These findings are discussed in terms of the biochemical abnormalities found in the central nervous system of demented subjects, and in terms of the possible pathogenetic involvement of an altered phenolsulphotransferase activity (and, in general, of a modified monoamine metabolism) in such derangements of biochemical systems often occuring in dementia of Alzheimer type.

Original Article

Abstract

We searched for CAG repeat expansions at the SCA1 and SCA3/MJD loci in nine families, including 15 examined patients, with autosomal dominant cerebellar ataxia type I from Morocco. Expansion of the CAG repeat was found in one family at the SCA1 and two at the SCA3/MJD locus, demonstrating the existence of genetic heterogeneity among ADCA type I families in Morocco. Instability during transmission was observed at both loci as in other unstable mutations. The phenotypes of the SCA1 and SCA3/MJD patients were similar.

Original Article

Abstract

The authors describe the occurrence of the thrombosis of the cerebral venous sinuses in a patient in coma due to a large hemispheric infarction attributed to the thrombosis of the left internal carotid artery. After his admission to the Intensive Care Unit, a fiberoptic catheter was advanced into the left internal jugular vein to monitor the jugular bulb blood oxygen saturation, and the controlater was catheterized In order to supply fluids and medications. Despite the aggressive treatment, the patient died and, at the autopsy a massive thrombosis of the internal jugular veins was found, which extended to all the sinuses, in the absence of evident carotideal abnormalities. The authors describe the possible mechanisms of the massive thrombosis.

Original Article

Abstract

We describe two patients with lesions at different levels of the septo‐hippocampal system. Both of them were selectively affected by anterograde amnesia, with a less severe retrograde amnesia. These data confirm that the integrity of the septohippocampal system is indispensable for the maintenance of normal memory and learning mechanisms and that the lesions along this fibre pathway, causing a functional and anatomic disconnection between the septal area (basal forebrain) and the medial temporal lobe structures, interfere with normal explicit memory functions.

Original Article

Abstract

A 42‐year‐old male patient presenting with clinical and biochemical evidence of adrenomyeloneuropathy (AMN) developed progressive spastic paraparesis and sensory ataxia from the age of 24. Biochemical studies showed elevated plasma concentration of saturated very‐long‐chain fatty acids (VLCFA). A nine‐base pair deletion in exon one within the adrenoieukodystrophy (ALD) gene (967del9) was detected by mutation screening on the patient's genomic DNA. This mutation predicts the replacement of aspartic acid 194 by valine (D194V) and deletion of the three following amino acids in the deduced ALD protein sequence. The subsequent reading frame appears to be unaffected. Molecular genetic analysis in the patient's family allowed definitive identification of a heterozygous carrier of ALD/AMN and exclusion of the ALD/AMN carrier status for one possible heterozygous female.

Original Article

Abstract

We present the clinical and electrophysiological findings of four patients with distal ulnar nerve lesions affecting, selectively, the deep palmar branch at the pisohamate hiatus. All presented with hand weakness and wasting, sparing the hypothenar muscles, without sensory manifestations. Two had palm pain. Three had possible precipitating trauma to the hand. All improved: three following decompression of constricting bands at the pisohamate hiatus and one spontaneously. At diagnosis, the ulnar motor amplitudes recording first dorsal interosseus (1st DI) were absent or very low. Recording the abductor digiti minimi (ADM), the amplitudes were normal or borderline. Needle EMG showed fibrillations and loss of motor unit potentials in all ulnar‐innervated muscles in the hand, except the ADM. Follow‐up ulnar conduction studies showed significant improvement of amplitudes recording 1st DI. Based on our cases and analysis of the literature, we conclude that lesions of the deep palmar branch of the ulnar nerve, distal to the branch to the ADM, are frequently caused by compression at the pisohamate hiatus, second only to compression by a ganglion. When treated surgically, this disorder carries good prognosis.

Short Report

Abstract

A 21‐year‐old woman with Gilles de la Tourette syndrome developed acute dystonia 24 h after ingesting 750 mg of tetrabenazine in a suicide attempt The symptoms were rapidly resolved on diazepam and orphenadrine administration. Acute dystonia caused by tetrabenazine is extremely rare, but may help us understand the pathophysiology of drug‐induced dystonic reactions. We suggest that acute dystonia in this patient was caused by catecholamine depletion and a subsequently reduced dopaminergic neurotransmission rather than by dopamine receptor blockade.

Short Report

Abstract

We describe a patient with the previously unreported association of chronic inflammatory demyelinating polyneuropathy (CIDP) and myasthenia gravis (MG). Immunosuppressive treatment with azathioprine and prednisone achieved clinical and electrophysiological remission of MG and improvement of CIDP. As ophthalmoplegia occurs infrequently in CIDP, the possibility of MG should be considered when this sign is present in a patient with CIDP. Since current therapy with corticosteroids, plasma exchange and other immunomodulating agents is effective against both diseases, their association may be undereported.

Case Report

Abstract

A 26‐year‐old man acutely developed bilateral sensory symptoms of carpal tunnel syndrome (CTS). Neurophysiological investigations confirmed the diagnosis of CTS with findings suggesting conduction block of sensory fibers. Endocrinological studies revealed a hyperthyroidism. He was treated with methimazole and propranolol with improvement of thyroid function. The neurophysiological and clinical follow‐up revealed a progressive improvement of CTS. The echography performed at wrist bilaterally failed to show any rough compressive factors in the carpal tunnel. The clinical, neurophysiological and endocrinological evolution suggest a relationship between hyperthyroidism and acute bilateral CTS.

Case Report

Abstract

Event‐related brain potentials (ERPs) were recorded in a 30 year old female patient with familial kinesigenic choreoathetosis and a group of control subjects. In line with previous observations the patient exhibited an enhanced amplitude of the early component of the contingent negative variation of the ERP in a two stimulus paradigm. Moreover, a greatly enhanced P3 amplitude was found in auditory and visual classification (oddball) paradigms. These results suggest a general upregulation of widespread subcortical projection systems leading to both, abnormal movements and abnormally high amplitudes of ERPs.

Original Article

Report on the Symposium “Neurology and Public Health in Europe”, organized by the WHO and the EFNS, Marseille, 15 September 1995

Abstracts

Abstracts from the 12th Annual Meeting of the Austrian Society for Neuroimaging, Vienna, Austria, November 3–4, 1995