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A Joutel

Publications and source records attributed to A Joutel.

At least 37 records · Page 2Linked to original sources
PubMed1998

Perichiasmatic granuloma occuring after radical mastoidectomy: MR findings.

A case of chronic chemical meningitis occurring after a radical mastoidectomy is reported. Imaging and surgical findings were suggestive of a dissemination of cholesteatoma debris within the subarachnoid spaces. Chemical meningitis has been described in epidermoid and dermoid cyst rupture. This report illustrates that clinicians should be aware of this possible complication. Skull base imaging is mandatory before considering the diagnosis of idiopathic meningitis. Only treatment of the abnormal communication between cerebrospinal fluid and middle ear may eradicate the origin of this rare meningitis.

Adult↗
PubMed1998

Differential diagnosis of a vascular leukoencephalopathy within a CADASIL family: use of skin biopsy electron microscopy study and direct genotypic screening.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a condition caused by mutations of Notch3 gene on chromosome 19. Ultrastructural analysis of skin vessels discloses typical granular osmiophilic material (GOM) within the vascular smooth muscle basal lamina. We describe a CADASIL family in which two members suffering from a vascular leukoencephalopathy were shown to be CADASIL phenocopies: clinical and magnetic resonance imaging (MRI) findings in these two patients were similar to those observed in their affected relatives. However, the skin biopsy performed on one of them did not reveal any GOM in the vascular smooth muscle cells, and the Notch3 mutation present in this family was shown to be absent in these two individuals. We emphasize the role of a direct DNA test for gene mutation to make a differential diagnosis between CADASIL and other forms of vascular leukoencephalopathy.

Adult↗
PubMed1998

Patterns of MRI lesions in CADASIL.

OBJECTIVE: To investigate the location and severity of MRI signal abnormalities in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). BACKGROUND: One hallmark of this arteriopathy due to mutations of Notch 3 gene is the presence of MRI signal abnormalities in both symptomatic and asymptomatic patients. METHODS: MRIs of 75 patients (43 with symptoms) were reviewed by a neuroradiologist masked to their clinical status. After assessing the presence of MRI lesions on T1- and T2-weighted images (T1-WI, T2-WI) in different subcortical regions, the severity of hyperintensities on T2-WI was scored using a global rating scale and a regional semiquantitative scale in the periventricular white matter (PV), deep white matter (WM), basal ganglia (BG), and infratentorial areas (IT). RESULTS: Sixty-eight patients (90%) had hyperintensities on T2-WI located in the white matter, more frequent in PV (96%) and WM (85%) than in the superficial white matter (25%). Hyperintensities also occurred in BG (60%) and brainstem (45%). Forty-seven patients (62%) presented with hypointensities on T1-WI. In one-third of the affected individuals, white matter hyperintensities occurred in the absence of small deep infarcts on T1-WI. The frequency and severity scores calculated for PV, WM, BG, or IT hyperintensities increase dramatically with age. These scores were higher in symptomatic compared with asymptomatic gene carriers. Dementia, Rankin score > 1, or both occurred only in the presence of diffuse white matter signal abnormalities. CONCLUSION: Our results suggest that different subcortical areas have different vulnerabilities to ischemia in CADASIL. The age effect we observed may show an accumulation of lesions with aging during the course of the disease. A prospective study is needed to investigate if the rating of MRI lesions is of prognostic value in CADASIL.

Adult↗
PubMed1997

Strong clustering and stereotyped nature of Notch3 mutations in CADASIL patients.

BACKGROUND: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy) is commonly overlooked or misdiagnosed owing to its recent identification and its variable mode of presentation. The defective gene in CADASIL is Notch3, which encodes a large transmembrane receptor. To set up a diagnostic test and to delineate the Notch3 domains involved in CADASIL., we undertook mutations analysis in this gene in a group of CADASIL patients. METHODS: 50 unrelated patients with CADASIL and 100 healthy controls were screened for mutations along the entire Notch3 sequence, by means of single-strand conformation polymorphism, heteroduplex, and sequence analysis. FINDINGS: Strongly stereotyped mis-sense mutations, located within the epidermal-growth-factor-like (EGF-like) repeats, in the extracellular domain of Notch3, were detected in 45 patients. Clustering of mutations within the two exons encoding the first five EGF-like repeats was observed (32 patients). All these mutations lead to loss or gain of a cysteine residue and therefore to an unpaired number of cysteine residues within a given EGF domain. None of these mutations was found in the 100 controls. INTERPRETATION: Because of the strong clustering and highly stereotyped nature of the pathogenetic mutations detected in CADASIL patients, and easy and reliable diagnostic test for CADASIL is feasible. The findings suggest that aberrant dimerisation of Notch3, due to abnormal disulphide bridging with another Notch3 molecule or with another protein, may be involved in the pathogenesis of this disorder.

Case-Control Studies↗
PubMed1997

Notch3 mutations in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a mendelian condition causing stroke and vascular dementia.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited condition whose key features include recurrent subcortical ischemic events, migraine attacks and vascular dementia in association with diffuse white-matter abnormalities seen on neuroimaging. Pathologic examination shows multiple small deep cerebral infarcts, a leukoencephalopathy and a nonatherosclerotic nonamyloid angiopathy involving mainly the media of small cerebral arteries. To progress in understanding the pathophysiological mechanisms of this condition, we undertook the identification of the mutated gene. We mapped the CADASIL gene on chromosome 19p13.1. More than 120 families have been referred to our lab. Genetic linkage analysis of 33 of these families allowed us to reduce the size of the genetic interval to less than 1 cM and to demonstrate the genetic homogeneity of this condition. In the absence of any candidate gene, we undertook positional cloning of this gene. We identified, within the CADASIL critical region, the human Notch3 gene, whose sequence analysis revealed deleterious mutations in CADASIL families co-segregating with the affected phenotype. These data establish that this gene causes CADASIL. Identification of the CADASIL gene will provide a valuable diagnostic tool for clinicians and could be used to estimate the prevalence of this underdiagnosed condition. It should help in the understanding of pathophysiological mechanisms of CADASIL and vascular dementia.

Adult↗
PubMed1997

Mapping of a second locus for familial hemiplegic migraine to 1q21-q23 and evidence of further heterogeneity.

Familial hemiplegic migraine (FHM) is an autosomal dominant variety of migraine with aura. We previously mapped an FHM gene on the short arm of chromosome 19. Mutations in this gene, recently shown to be the alpha1 subunit of a P/Q-type voltage-dependent calcium channel, CACNL1A4, are involved in approximately 50% of unselected FHM families and in all families where migraine attacks are associated with permanent cerebellar ataxia. As a first step toward the identification of other FHM genes, we conducted a genetic linkage analysis in one large French pedigree and showed significant linkage to two microsatellite markers D1S2635 (Zmax: 3.33 at theta = 0.05) and D1S2705 (Zmax: 3.64 at theta = 0.05), establishing the existence of a second locus for FHM (FHM2) on chromosome 1q21-q23. Analysis of six additional FHM families favored linkage to this locus in two of them; linkage was excluded in the last four families, indicating further heterogeneity. Chromosome 1-linked families differ from the ones linked to chromosome 19, because penetrance in those families is much lower, and in some of their members, epileptic seizures occur during severe migraine attacks.

Chromosome Mapping↗
PubMed1997

[CADASIS. Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalophathy].

CADASIL is an inherited arterial disease of the brain with an autosomal dominant pattern of transmission. The mapping of the affected gene in 1993 allowed us to describe the natural history of the disease. In some patients, the disease starts with attacks of migraine with aura at a mean age of 30 years. The most frequent clinical manifestations are subcortical transient ischemic attacks or completed strokes usually occurring between 40 and 50 years of age which are sometimes associated with severe mood disturbances. The disease leads about two decades later to death after a variable period of subcortical dementia associated with pseudobulbar palsy and urinary incontinence. In one given family, the severity of the clinical presentation varies among the affected subjects. MRI is always abnormal in symptomatic subjects. It shows more or less confluent hypersignals on T2-weighted images in white-matter and basal ganglia and hyposignals on T1-weighted images in the same regions corresponding to small infarcts. These signal abnormalities are even observed a long time before the onset of clinical manifestations as they are present in totally asymptomatic young family members. Histologic studies show a widespread palor of white-matter and multiple small infarcts in the white-matter and basal ganglia underlaid by a small artery disease of the brain. Electron microscopy studies show that the media of the white-matter and leptomeningeal small arteries is thickened by a granular, eosinophilic and non-amyloid material of undetermined origin close to the smooth muscle cells. These ultrastructural wall abnormalities have been observed in other arteries, particularly in muscular and skin arteries. Mutations of Notch3 gene located on chromosome 19 are responsible for the disease. The diagnosis should be discussed in subjects with a history of unexplained subcortical ischemic strokes, attacks of migraine with aura, mood disorders of subcortical dementia whenever associated with MRI signal abnormalities in white-matter and basal ganglia.

Brain↗
PubMed1996

A human homolog of bacterial acetolactate synthase genes maps within the CADASIL critical region.

CADASIL, a recently identified autosomal dominant condition characterized by the recurrence of subcortical infarcts leading to dementia, was previously mapped to chromosome 19p13.1 within a 2-cM interval, D19S226-D19S199. No recombination event was observed with D19S841, a highly polymorphic microsatellite marker isolated from a cosmid mapped to this region. We recently identified within this cosmid a conserved sequence that we used to screen a fetal brain cDNA library and isolated an ubiquitous and abundantly transcribed gene. We did not detect any mutation of this gene in CADASIL patients, suggesting that it is not implicated in this disorder. Interestingly, this gene encodes a putative protein homologous to several thiamine pyrophosphate-binding proteins previously identified in bacteria, yeast, and plants. The proteins with the highest degree of similarity were the acetolactate synthase enzymes which, in prokaryotes, are involved in the branched chain amino acid biosynthetic pathway, raising fascinating questions on the yet unknown function of this gene in mammals.

Acetolactate Synthase↗
PubMed1996

Notch3 mutations in CADASIL, a hereditary adult-onset condition causing stroke and dementia.

Stroke is the third leading cause of death, and vascular dementia the second cause of dementia after Alzheimer's disease. CADASIL (for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) causes a type of stroke and dementia whose key features include recurrent subcortical ischaemic events and vascular dementia and which is associated with diffuse white-matter abnormalities on neuroimaging. Pathological examination reveals multiple small, deep cerebral infarcts, a leukoencephalopathy, and a non-atherosclerotic, non-amyloid angiopathy involving mainly the small cerebral arteries. Severe alterations of vascular smooth-muscle cells are evident on ultrastructural analysis. We have previously mapped the mutant gene to chromosome 19. Here we report the characterization of the human Notch3 gene which we mapped to the CADASIL critical region. We have identified mutations in CADASIL patients that cause serious disruption of this gene, indicating that Notch3 could be the defective protein in CADASIL patients.

Adult↗
PubMed1996

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, genetic homogeneity, and mapping of the locus within a 2-cM interval.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently identified autosomal dominant cerebral arteriopathy characterized by the recurrence of subcortical infarcts leading to dementia. A genetic linkage analysis conducted in two large families recently allowed us to map the affected gene on chromosome 19 in a 12-cM interval bracketed by D19S221 and D19S215. In the present study, these first 2 families and 13 additional ones, including a total of 199 potentially informative meiosis, have been genotyped with eight polymorphic markers located between D19S221 and D19S215. All families were linked to chromosome 19. The highest combined lod score (Zmax = 37.24 at theta = .01) was obtained with marker D19S841, a new CAn microsatellite marker that we isolated from chromosome 19 cosmids. The recombinant events observed within these families were used to refine the genetic mapping of CADASIL within a 2-cM interval that is now bracketed by D19S226 and D19S199 on 19p13.1. These data strongly suggest the genetic homogeneity of this recently identified condition and establish the value of its clinical and neuroimaging diagnostic criteria. Besides their importance for the ongoing positional cloning of the CADASIL gene, these data help to refine the genetic mapping of CADASIL relative to familial hemiplegic migraine and hereditary paroxysmal cerebellar ataxia, conditions that we both mapped within the same chromosome 19 region.

Cerebral Arterial Diseases↗
PubMed1996

[CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy)].

Recently identified, CADASIL is a diffuse disease of small arteries, predominating in the brain. It starts during mid-adulthood and is characterized by recurrent ischemic events (transient or permanent), attacks of migraine with aura, severe mood disorders, subcortical dementia and, at MRI, a white spread leukoencephalopathy. There is so far no specific treatment and death occurs after a mean of twenty years. CADASIL is an autosomal dominant condition and the gene Notch 3 is located on chromosome 19, in the same region as another neurological disorder, familial hemiplegic migraine.

Brain Ischemia↗
PubMed1995

Clinical spectrum of CADASIL: a study of 7 families. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited arterial disease of the brain recently mapped to chromosome 19. We studied 148 subjects belonging to seven families by magnetic resonance imaging and genetic linkage analysis. 45 family members (23 males and 22 females) were clinically affected. Frequent signs were recurrent subcortical ischaemic events (84%), progressive or stepwise subcortical dementia with pseudobulbar palsy (31%), migraine with aura (22%), and mood disorders with severe depressive episodes (20%). All symptomatic subjects had prominent signal abnormalities on MRI with hyperintense lesions on T2-weighted images in the subcortical white-matter and basal ganglia which were also present in 19 asymptomatic subjects. The age at onset of symptoms was mean 45 (SD [10-6]) years, with attacks of migraine with aura occurring earlier in life (38.1 [8.03] years) than ischaemic events (49.3 [10.7] years). The mean age at death was 64.5 (10.6) years. On the basis of MRI data, the penetrance of the disease appears complete between 30 and 40 years of age. Genetic analysis showed strong linkage to the CADASIL locus for all seven families, suggesting genetic homogeneity. CADASIL is a hereditary cause of stroke, migraine with aura, mood disorders and dementia. The diagnosis should be considered not only in patients with recurrent small subcortical infarcts leading to dementia, but also in patients with transient ischaemic attacks, migraine with aura or severe mood disturbances, whenever MRI reveals prominent signal abnormalities in the subcortical white-matter and basal ganglia. Clinical and MRI investigations of family members are then crucial for the diagnosis which can be confirmed by genetic linkage analysis. The disease is probably largely undiagnosed.

Adult↗
PubMed1995

[Hemiplegic migraine].

By analogy with ophthalmic migraine, hemiplegic migraine is defined by the occurrence during the attacks of unilateral weakness. This simple definition is however far from reflecting the wide range of clinical situations reported under this term. Familial hemiplegic migraine (FHM) is a well individualized autosomal dominant condition. Attacks start in childhood, adolescence, or early adulthood. They invariably include a unilateral weakness lasting 30 to 60 minutes and almost always associated with visual, sensory, or speech disturbances. They are occasionally very severe with a dense hemiplegia, confusion, coma or fever, but they always completely recover. Brain neuroimaging is normal. In 20% of the families, migraine is associated with permanent neurological signs, mainly nystagmus and cerebellar ataxia. FHM is a genetically heterogeneous condition, with half of the families linked to chromosome 19 and the other half in which this link is excluded. By contrast to FHM, which is a well defined entity, other varieties of so called hemiplegic migraine do not deserve to be individualized as such. They include attacks of migraine with typical aura when a unilateral weakness is part of the aura, severe hemiplegic attacks similar to those reported in FHM but sporadic, migrainous infarcts with hemiplegia, and, for some authors, alternating hemiplegia of childhood. The pathogenesis of all these conditions and of migraine itself remaining largely unknown, it is currently impossible to know whether or not they share common pathophysiologic mechanisms. The identification of the gene on chromosome 19 and the discovery of other genes will be major steps to elucidate this question.

Adolescent↗
PubMed1995

A gene for hereditary paroxysmal cerebellar ataxia maps to chromosome 19p.

Hereditary paroxysmal cerebellar ataxia (HPCA) is an autosomal dominant disorder characterized by the recurrence of intermittent attacks of vestibulocerebellar ataxia lasting from 15 minutes to a few days. The number of attacks is often significantly decreased by acetazolamide treatment. Neurological examination shows a permanent gaze-evoked nystagmus, as well as a mild cerebellar ataxia in most patients. The paroxysmal feature of this condition is shared by another autosomal dominant neurological condition, familial hemiplegic migraine (FHM), a condition in which permanent cerebellar signs have also been reported in some families. Although hemiplegic migraine has never been reported in patients with HPCA, we hypothesized, based on the latter observations, that HPCA and FHM may be allelic disorders. We previously mapped a gene responsible for FHM on the short arm of chromosome 19. We performed linkage analysis with 6 markers spanning the FHM interval on a large HPCA family. Significant lod scores were obtained with 3 markers: D19S244 (LS = 3.71), D19S221 (3.60), and D19S226 (3.54) at theta = 0. Haplotype and multipoint linkage analysis established that the most likely location was the same interval of 30 cM encompassing the chromosome 19 FHM locus.

Cerebellar Ataxia↗
PubMed1995

Autosomal dominant migraine with MRI white-matter abnormalities mapping to the CADASIL locus.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an autosomal dominant cerebral arteriopathy mapped to chromosome 19 and characterized mainly by recurrent subcortical ischemic strokes and extensive white-matter signal abnormalities (WMAs) on magnetic resonance imaging. Other clinical features include migraine attacks and progressive subcortical dementia. Herein, we describe several members of the same family who suffered migraine attacks, mostly with aura, associated with WMAs, segregating with an autosomal dominant pattern of inheritance. One individual had a progressive subcortical dementia with similar WMAs. Although ischemic stroke, one of the hallmarks of CADASIL, was not present in this family, we hypothesized that the present disorder resulted from an alteration of the CADASIL gene. Genetic linkage analysis, using four chromosome 19 markers spanning the CADASIL locus, supports this hypothesis.

Adult↗
PubMed1994

[Familial hemiplegic migraine. Localization of a responsible gene on chromosome 19].

Familial hemiplegic migraine is an autosomal dominant disorder of unknown pathogenesis in which the migrainous attacks are marked by the occurrence of a transient hemiplegia during the aura. The aim of our study was the identification of the affected gene. The first step was the chromosomal mapping of the affected gene, for which we used a "candidate gene" strategy. The first candidate gene was the gene responsible for CADASIL. While investigating CADASIL, mapped previously to chromosome 19, we observed that some patients had recurrent attacks of migraine with aura. Although the clinical and neuroimaging features of familial hemiplegic migraine differ markedly from CADASIL, we hypothesized that the same gene could be involved in the pathogenesis of both conditions. We chose two large pedigrees for linkage analysis of familial hemiplegic migraine. A maximum lodsore > 8 was found with two markers that are strongly linked to CADASIL. Multilocus linkage analysis located the affected gene within an interval of about 30 cM on chromosome 19, containing the gene responsible for CADASIL. At this step it's not possible to conclude that CADASIL and familial hemiplegic migraine are due to the same mutated gene. It will be necessary to analyse other familial hemiplegic migraine and CADASIL families in order to reduce the size of their respective interval and ultimately identify the mutated gene(s).

Chromosomes, Human, Pair 19↗
PubMed1994

Genetic heterogeneity of familial hemiplegic migraine.

Familial hemiplegic migraine (FHM) is an autosomal dominant variety of migraine with aura. We previously mapped a gene responsible for this disorder to the short arm of chromosome 19, within a 30-cM interval bracketed by D19S216 and D19S215. Linkage analysis conducted on two large pedigrees did not show any evidence of heterogeneity, despite their clinical differences due to the presence, in one family, of cerebellar ataxia and nystagmus. Herein we report linkage data on seven additional FHM families including another one with cerebellar ataxia. Analysis was conducted with a set of seven markers spanning the D19S216-D19S215 interval. Two-point and multipoint lod score analyses as well as HOMOG testing provided strong evidence for genetic heterogeneity. Strong evidence of linkage was obtained in two families and of absence of linkage in four families. The posterior probability of being of the linked type was > .95 in the first two families and < .01 in four other ones. It was not possible to draw any firm conclusion for the last family. Thus, within the nine families so far tested, four were linked, including those with associated cerebellar ataxia. We could not find any clinical difference between the pure FHM families regardless of whether they were linked. In addition to the demonstration of genetic heterogeneity of FHM, this study also allowed us to establish that the most likely location of the gene was within an interval of 12 cM between D19S413 and D19S226.

Ataxia↗