C-fos expression after single and kindled audiogenic seizures in Wistar rats

In naive Wistar rats susceptible to sound, a single audiogenic seizure induced the expression of c-fos in the subcortical auditory nuclei whereas the forebrain was almost completely devoid of any labelling. After kindling of audiogenic seizures by 40 daily exposures to sound, the seizure induced a strong c-fos expression in the amygdala, the piriform cortex, the hippocampus and the neocortex. These results confirm: (1) that audiogenic seizures are brain-stem seizures related to dysfunction of auditory pathways, and (ii) that kindling of audiogenic seizures recruits forebrain and limbic structures into the seizure network.

Molecular phylogeny of part of the env gene of HIV-1 strains isolated in Côte d'Ivoire

OBJECTIVES

To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d'Ivoire, and to determine the extent to which phylogenetic trees based on sequence information of part of the env gene containing the principal neutralizing domain are representative for documenting genetic variability.

DESIGN

Phylogenetic comparison of 13 HIV-1 strains isolated from patients in Abidjan with previously documented HIV-1 strains of different geographic origin.

METHODS

To sequence a 900 base-pair fragment of the env gene containing V3, V4, V5 and the beginning of gp41 of three to four clones per isolate. Phylogenetic tree analysis was performed with the software package TREECON.

RESULTS

Eleven HIV-1 isolates of Abidjan were classified as genotype A, while two were classed as genotypes B and D. Intra-genotype A distances at the nucleotide level were a maximum of 14.1%. Inter-genotype distances between genotype A and genotypes B, C, and D varied from 16.0 to 22.6%. Phylogenetic trees, based on sequence data of a 300 base-pair fragment containing the V3 loop, showed significant differences in tree topology and statistical confidence with phylogenetic trees based on sequence data of the 900 base-pair env fragment.

CONCLUSIONS

Genotype A Côte d'Ivoire HIV-1 strains, which comprise 11 out of 13 isolates, predominate in Abidjan, which may indicate a local burst of particular variants. Phylogenetic trees should be interpreted with caution when based on a more limited number of nucleotides, such as the V3 region.

Neurofibromatosis type one and West syndrome: a relatively benign association

Fifteen patients with neurofibromatosis type one (NF1) and West syndrome (WS) were studied. The evolution of WS was clearly different from that seen in the other neurocutaneous syndromes, especially tuberous sclerosis. Steroids were efficacious and spasms disappeared. There was no relapse after discontinuation of steroids and antiepileptic drugs were successfully stopped several years later. Mental outcome was also very good. The association of both conditions does not seem to be a coincidence. WS with NF1 seems remarkably benign and resembles idiopathic WS more than symptomatic WS.

Collaborative study of the molecular epidemiology of Tay-Sachs disease in Europe

Tay-Sachs disease is a lipidosis due to the deficiency of the lysosomal hexosaminidase A. In order to understand the molecular mechanisms of this enzyme deficiency we studied 42 patients of different ethnic origins diagnosed in Europe. The strategy used consists in HEXA cDNA amplification followed by allele-specific oligonucleotide analysis for the frequent mutations, and by chemical cleavage mismatch and denaturing gradient gel electrophoresis for the detection of new mutations. 90% of alleles were clarified in this way, showing a high heterogeneity of HEXA lesions in Tay-Sachs disease. 28 different mutations were found, 20 being identified for the first time in this group of patients.

Double-blind, randomized trial of diazepam versus placebo for prevention of recurrence of febrile seizures

The aim of this study was to evaluate the efficacy and tolerance of intermittent oral administration of diazepam during hyperthermia for reducing the recurrence of febrile seizure: 185 children, between 8 months and 3 years of age, with a first febrile seizure and normal neurologic development, were randomly assigned in a double-blind fashion to receive orally administered diazepam (0.5 mg/kg, then 0.20 mg/kg, every 12 hours) or placebo, whenever the rectal temperature was more than 38 degrees C. The main criterion of efficacy was the seizure recurrence rate 1 year after the first seizure. The duration of the study was 3 years; eight different centers in France participated. There were 462 febrile episodes and 1000 days with prophylactic treatment. The recurrence rates did not differ between the diazepam group (16%) and the placebo (19.5%) group. The children with recurrent seizures were significantly younger at the time of the first seizure (17 +/- 6.9 months) than children without a recurrent seizure (21 +/- 8.5 months). In children with recurrent seizures, prophylactic treatment was correctly administered to only 1 of 15 children in the diazepam group and to 7 of 18 children in the placebo group. The following were the reasons for this poor cooperation: convulsion being the first manifestation of the fever (seven cases in each group), parents neglecting to give treatment (nine cases), and refusal to take treatment by two children. Side effects were similar in the two groups except for hyperactivity, which was more frequent in the diazepam (138 days) than in the placebo (34 days) group. Intermittent oral administration of diazepam at the onset of fever offered no advantage over placebo in preventing recurrence of seizure. This finding probably reflects a lack of efficacy of the intermittent method rather than of diazepam itself.

Encephalopathy with calcifications of the basal ganglia in children. A reappraisal of Fahr's syndrome with respect to 14 new cases

Calcifications of the basal ganglia are described under the heading of "Fahr's syndrome". The clinical pattern is variable and the syndrome may be sporadic or familial. This study describes a personal series of 14 cases of encephalopathy with calcification of the basal ganglia and reviews the literature cases. A four-group classification is proposed. The first group includes encephalopathy, microcephaly, dwarfism, retinal degeneration or optic atrophy, symmetrical patchy demyelination with calcifications and probable autosomal recessive inheritance. Some cases have an early onset, a rapid evolution. Others have a later onset, longer course and retinal degeneration. In the second group, the children suffer from a congenital encephalopathy or a cerebral palsy without clear deterioration, without short stature, ocular impairment or persistent CSF abnormalities. This group has not been reported in the literature. The cases do not seem to be genetic. The precise cause in unknown but a sporadic non progressive anoxo-ischemic, or viral prenatal disease is suggested. In the third group, the association of encephalopathy, microcephaly, and persistent CSF lymphocytosis, has a high recurrence rate. The pathogenesis is still a matter of dispute. The fourth group is characterized by autosomal dominant calcifications of the basal ganglia with or without neurological abnormalities. Finally calcium metabolism disorders and mitochondrial encephalomyopathy may be associated with calcifications of the basal ganglia.

Age-related changes in the density and morphology of plaques and neurofibrillary tangles in Down syndrome brain

Fifteen cases of Down syndrome between age 25-59 years were examined neuropathologically. A variety of histological methods were used to identify plaques and neurofibrillary tangles (NFT). All cases had some plaques or NFT, but their density was generally not high before the age of 40 years. Plaques and NFT tended to appear at about the same time although in somewhat different cortical areas. Changes appeared first in the dentate gyrus, subiculum, entorhinal and association neocortex. The stages in the evolution of plaque morphology were quantitated in the dentate gyrus. The earliest change was the extracellular accumulation of fibrillar material with the histological characteristics of amyloid. In the second stage there was an exuberant neuritic reaction with swollen processes that contained little or no paired helical filaments (PHF). Stage 1 and 2 plaques were seen predominantly between ages 25-38 years, and were not obviously associated with blood vessels or glial cells. In the third stage of plaque formation neurites appeared to degenerate, contained more PHF, and surrounded a compact core of amyloid. Stage 3 plaques were never very numerous, and were seen only between ages 48-55 years. Stage 4 plaques consisted of a cloud of silver-positive debris. They appeared to be the final stage and were the predominant morphological type in the dentate gyrus after age 48 years. Amyloid angiopathy was present only after age 48, and was a prominent finding in only three cases.

[Cerebellar ataxia preceding cutaneous symptoms in chickenpox]

The authors describe a case of cerebellar ataxia developing 8 days before the exanthema of varicella. Evolution was quickly favorable. On the occasion of this rare observation, the pathophysiology of the neurological complications of varicella are discussed.

Sonographic diagnosis of lissencephaly

Lissencephaly, a developmental malformation characterized by absence of sulci, may be suggested in dysmorphic or epileptic infants. Real time ultrasonographic findings correlated with typical electroencephalographic abnormalities establish the diagnosis.

[Benign epileptic infantile spasms]

Among 100 infants with infantile spasms studied before treatment, 14 had idiopathic spasms with a favourable outcome. They had a normal development, including reaching for objects before the age of 5 months and moderate regression without loss of eye following. Although it was hysarhythmic, the EEG tracing showed identifiable basic activity and sleep spindles; there was no slow waves focus even after diazepam administration and the spasms were "independent" even during a cluster. This type of infantile spasms seems to be a particular type of non-lesional epilepsy. It contrasts with idiopathic spasms of unfavourable outcome that apparently result from a preexisting and overlooked focal lesion responsible of later cognitive troubles.

[Fetal torsades de pointe and the long QT syndrome]

The authors report a case of pregnancy interrupted by caesarian section at 38 weeks' gestation for attacks of fetal ventricular tachycardia. The recording of a long QT interval at birth indicated a diagnosis of fetal torsades de pointe. These attacks recurred 2 hours after birth leading to cardiac arrest. The arrhythmia was immediately controlled by betablockers therapy. The diagnostic, epidemiological and physiopathological features of the long QT syndrome are reviewed. The links with maturation of the sympathetic nervous system are recalled. Finally, a diagnostic and therapeutic strategy is proposed, based on the results of fetal echocardiography.

[Extradural hematoma in children under 1 year of age]

The authors report 3 cases of epidural hematoma in infants under one year of age. The trauma had been minimal with a long symptom-free interval preceding the first clinical symptoms: anemia and its consequences, pallor, bradycardia, and finally shock. CT scan revealed the hematoma. In one case, it showed an asymptomatic hematoma which posed a therapeutic problem.

[Choroid plexus papilloma (author's transl)]

The authors report a new case of choroid plexus papilloma. Hydrocephalus produced by this tumour has special features. Diagnosis is made by CAT scan. Despite surgery and the begnignity of such tumours, prognosis is generally poor. In the reported case two radiological pictures over a 5 year period did not any increasing of the size of the tumour.