Search PubMed⌕ Search

Biomedical subjects

Michel D Ferrari

Publications and source records attributed to Michel D Ferrari.

16 recordsLinked to original sources
PubMed2016

Gene co-expression analysis identifies brain regions and cell types involved in migraine pathophysiology: a GWAS-based study using the Allen Human Brain Atlas.

Migraine is a common disabling neurovascular brain disorder typically characterised by attacks of severe headache and associated with autonomic and neurological symptoms. Migraine is caused by an interplay of genetic and environmental factors. Genome-wide association studies (GWAS) have identified over a dozen genetic loci associated with migraine. Here, we integrated migraine GWAS data with high-resolution spatial gene expression data of normal adult brains from the Allen Human Brain Atlas to identify specific brain regions and molecular pathways that are possibly involved in migraine pathophysiology. To this end, we used two complementary methods. In GWAS data from 23,285 migraine cases and 95,425 controls, we first studied modules of co-expressed genes that were calculated based on human brain expression data for enrichment of genes that showed association with migraine. Enrichment of a migraine GWAS signal was found for five modules that suggest involvement in migraine pathophysiology of: (i) neurotransmission, protein catabolism and mitochondria in the cortex; (ii) transcription regulation in the cortex and cerebellum; and (iii) oligodendrocytes and mitochondria in subcortical areas. Second, we used the high-confidence genes from the migraine GWAS as a basis to construct local migraine-related co-expression gene networks. Signatures of all brain regions and pathways that were prominent in the first method also surfaced in the second method, thus providing support that these brain regions and pathways are indeed involved in migraine pathophysiology.

Atlases as Topic↗
PubMed2003

Evaluation of diagnostic NOTCH3 immunostaining in CADASIL.

CADASIL is caused by mutations in the NOTCH3 gene. Although increasingly recognized as a disease entity, the diagnostic confirmation can be lengthy or inconclusive. Recently, NOTCH3 immunostaining of skin biopsy specimens has been introduced as a new diagnostic test. The aim of this study was to independently assess the diagnostic value of NOTCH3 immunostaining, and determine whether the degree of immunostaining correlates with other disease parameters. We determined NOTCH3 mutation carrier status in 62 symptomatic and asymptomatic individuals from 15 CADASIL families. Skin biopsy specimens of these individuals, as well as of a disease control group, were immunostained with NOTCH3 antibody and blindly analyzed by two independent observers to determine sensitivity and specificity. A semiquantitative NOTCH3 immunostaining score was correlated with clinical, genetic and MRI parameters. The sensitivity was 90.2% and 85.4%, respectively, for the two observers, the specificity 95.2% and 100%; both lower than previously reported. Certain NOTCH3 mutations may underlie false-negative results. False-positive results were found in a non-mutated control, and also in one disease control. There was no difference in immunostaining between symptomatic and asymptomatic NOTCH3 mutated individuals. Furthermore, the NOTCH3 immunostaining score did not correlate with clinical or MRI parameters. NOTCH3 immunostaining is a supportive, but not definitive, CADASIL diagnostic test, and should be interpreted in the context of clinical and radiological data. Confirmation by DNA analysis is requisite for positive results, and when there exists high clinical suspicion, also for negative results.

Adult↗
PubMed2003

Voxel-based morphometry in hypocretin-deficient narcolepsy.

STUDY OBJECTIVES: Recent studies suggest that narcolepsy is caused by degeneration of hypocretin (orexin) producing neurons. To find evidence for this hypothesis, we aimed to detect structural changes in the hypothalamus and/or hypocretin projection areas of patients with narcolepsy. DESIGN: We used voxel-based morphometry (VBM), an unbiased MRI morphometric method with a high sensitivity for subtle changes in gray and white matter volumes. SETTING: Image acquisition was carried out in the department of Radiology at Leiden University Medical Center; image post-processing was performed in the Wellcome Department of Cognitive Neurology, London. PARTICIPANTS: Fifteen narcoleptic patients were studied, all having cataplexy and typical findings on Multiple Sleep Latency Testing. All patients were HLA-DQB1*0602 positive and hypocretin-1 deficient. The control group consisted of 15 age and sex matched healthy subjects. MEASUREMENTS AND RESULTS: We found no differences in global gray or white matter volumes between patients and controls. Furthermore, regional gray or white matter volumes in the hypothalamus and hypocretin projection areas did not differ between patients and controls. CONCLUSIONS: VBM failed to show structural changes in the brains of patients with narcolepsy. This suggests that narcolepsy either is associated with microscopic changes undetectable by VBM or that functional abnormalities of hypocretin neurons are not associated with structural correlates.

Adult↗
PubMed2003

Incipient CADASIL.

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by mutations in the NOTCH3 gene. Knowledge of disease expression in young adult NOTCH3 mutation carriers (MCs) is limited. OBJECTIVE: To characterize clinical, neuropsychological, and radiological status in NOTCH3 MCs younger than 35 years. DESIGN: Clinical characterization and blinded survey comparing MCs with non-MCs. SETTING: Referral center. PARTICIPANTS: Individuals younger than 35 years who were at a 50% risk of a NOTCH3 mutation, from our CADASIL database. Thirteen individuals, from 8 families, met the criteria. METHODS: Comprehensive clinical, genetic, neuropsychological, and radiological investigations. Magnetic resonance images were scored according to a standardized white matter hyperintensities rating scale. RESULTS: Six individuals, from 5 families, were MCs. Clinical symptoms consisted of migraine (with aura), stroke, and stroke-like episodes. We did not find evidence for psychiatric disturbances, functional disability, or cognitive dysfunction, compared with non-MCs. Radiologically, a characteristic magnetic resonance imaging lesion pattern emerged for all MCs. This comprised white matter hyperintensities in the anterior temporal lobes, the frontal lobes, and the periventricular frontal caps. CONCLUSIONS: Migraine (with aura) and stroke can present in NOTCH3 MCs younger than 35 years; however, more importantly, physical function and cognition are intact. Possible subtle cognitive dysfunction needs to be assessed in a larger study. White matter hyperintensities on magnetic resonance imaging are characteristic, and are consistently visualized from the age of 21 years and onward. Awareness of the clinical and radiological features of CADASIL in those younger than 35 years should increase early diagnosis and allow for customized counseling of young adults from families with CADASIL.

Adult↗
PubMed2003

Novel mutations in the Na+, K+-ATPase pump gene ATP1A2 associated with familial hemiplegic migraine and benign familial infantile convulsions.

Familial hemiplegic migraine (FHM) is a rare, severe, autosomal dominant subtype of migraine with aura. Up to 75% of FHM families have a mutation in the P/Q-type calcium channel Ca(v)2.1 subunit CACNA1A gene on chromosome 19p13. Some CACNA1A mutations also may cause epilepsy. Here, we describe novel missense mutations in the ATP1A2 Na(+),K(+)-ATPase pump gene on chromosome 1q23 in two families with FHM. The M731T mutation was found in a family with pure FHM. The R689Q mutation was identified in a family in which FHM and benign familial infantile convulsions partially cosegregate. In this family, all available affected family members with FHM, benign familial infantile convulsions, or both, carry the ATP1A2 mutation. Like FHM linked to 19p13, FHM linked to 1q23 also involves dysfunction of ion transportation and epilepsy is part of its phenotypic spectrum.

Adolescent↗
PubMed2003

Myocardial infarction in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an angiopathy caused by mutations in the NOTCH3 gene. Typical microvascular changes are found throughout the arterial tree, but the documented disease expression is confined to the central nervous system. In an ongoing CADASIL study, we noted a number of patients with early acute myocardial infarction (before the age of 50 years), as well as patients with electrocardiogram (ECG) abnormalities. We analyzed these data to determine whether myocardial ischemia is associated with NOTCH3 mutations. ECGs were recorded in mutated (n = 41) and nonmutated (n = 22) individuals from 15 genetically confirmed CADASIL families, and blindly classified according to the Minnesota code. Cardiologic history was assessed and cardiovascular disease risk factors were determined. Evidence for myocardial infarction was defined as a positive history for acute myocardial infarction and/or a Minnesota Code 1 (Q-waves) on ECG. We examined CADASIL myocardial tissue ultrastructurally and immunohistochemically for evidence of microangiopathy. We found that almost 25% (10/41) of mutation carriers had evidence of myocardial infarction, versus none of the 22 nonmutation carriers (p = 0.011). Five had a medical history of acute myocardial infarction, and 5 had current pathologic Q-waves on ECG. Acute myocardial infarction occurred at a mean age of 39.6 +/- 5.22 years, and predated major neurologic symptoms of CADASIL in all cases. Pathologic examination of myocardial tissue revealed typical CADASIL arteriopathic changes of the coronary microvasculature. To our knowledge, this is the first study showing that NOTCH3 mutation carriers may be at increased risk of early acute myocardial infarction, expanding CADASIL disease expression beyond the central nervous system to include the heart.

Acute Disease↗
PubMed2003

Cerebral hemodynamics and white matter hyperintensities in CADASIL.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary small-vessel disease caused by mutations in the NOTCH3 gene on chromosome 19. On magnetic resonance imaging (MRI), subcortical white matter hyperintensities and lacunar infarcts are visualized. It is unknown whether a decrease in cerebral blood flow or cerebrovascular reactivity is primarily responsible for the development of white matter hyperintensities and lacunar infarcts. The authors used phase-contrast MRI in 40 NOTCH3 mutation carriers (mean age 45 +/- 10 years) and 22 nonmutated family members (mean age 39 +/- 12 years), to assess baseline total cerebral blood flow (TCBF) and cerebrovascular reactivity after acetazolamide. Mean baseline TCBF was significantly decreased in NOTCH3 mutation carriers. In young subjects, baseline TCBF was significantly lower than in nonmutation carriers (mean difference 124 mL/min). Furthermore, baseline TCBF did not differ significantly between mutation carriers with minimal and mutation carriers with moderate or severe white matter hyperintensities. No significant difference in mean cerebrovascular reactivity was found between mutation carriers and nonmutation carriers. This study suggests that a decrease in baseline TCBF in NOTCH3 mutation carriers precedes the development of white matter hyperintensities.

Adult↗
PubMed2002

Comparison of weakness progression in inclusion body myositis during treatment with methotrexate or placebo.

We investigated whether 5 to 20mg per week oral methotrexate could slow down disease progression in 44 patients with inclusion body myositis in a randomized double-blind placebo-controlled study over 48 weeks. Mean change of quantitative muscle strength testing sum scores was the primary study outcome measure. Quantitative muscle strength testing sum scores declined in both treatment groups, -0.2% for methotrexate and -3.4% for placebo (95% confidence interval = -2.5% to +9.1% for difference). There were also no differences in manual muscle testing sum scores, activity scale scores and patients' own assessments after 48 weeks of treatment. Serum creatine kinase activity decreased significantly in the methotrexate group. We conclude that oral methotrexate did not slow down progression of muscle weakness but decreased serum creatine kinase activity.

Administration, Oral↗
PubMed2002

The hypothalamus in episodic brain disorders.

Episodic brain disorders (EBD) form an intriguing group of neurological diseases in which at least some of the symptoms occur in attacks. The hypothalamus integrates many brain functions, including endocrine and autonomic control, and governs various body rhythms. It seems a likely site in which the initiation of attacks of EBD can be modulated. Indeed, the hypothalamus has a crucial role in EBD such as narcolepsy and cluster headache. The same may be true for migraine and depression. Here we summarise the evidence supporting an important role for the hypothalamus in the initiation of disease episodes in various EBD. Study of the various pathophysiological concepts of EBD within the context of the hypothalamus may prove a fruitful example of cross-fertilisation between various research areas.

Animals↗
PubMed2002

Tripstar: a comprehensive patient-based approach to compare triptans.

Several second-generation triptans have been introduced that differ in their pharmacologic profiles relative to each other and to sumatriptan. As therapeutic options multiply, clinicians must be able to distinguish among these compounds. Recently, a meta-analysis was conducted on data from 53 double-blind, randomized, placebo- or active-controlled trials involving over 24,000 patients receiving oral triptans. Results indicated that almotriptan 12.5 mg, rizatriptan 10 mg, and eletriptan 80 mg are generally superior to sumatriptan 100 mg based on individual treatment attributes, such as pain relief, sustained pain freedom, consistency of response, and tolerability. Meta-analyses are limited, however, as the analysis can only be performed for individual end points, whereas patients and prescribers balance a variety of treatment attributes when assessing drug acceptability. A flexible overall scoring system ("Tripstar") is proposed that compares triptans to a hypothetical "ideal" using meta-analysis data combined with ratings of the relative importance of clinically relevant treatment criteria. An informal test of the Tripstar model indicated that sumatriptan is most similar to a hypothetical ideal for both mild and severe migraine, primarily due to its high worldwide clinical exposure. However, after exclusion of worldwide exposure as a contributing factor, almotriptan 12.5 mg is most similar to the ideal, principally because of its good tolerability. Further tests of the Tripstar model are planned that will gauge the relative importance of a broader range of attributes.

Acute Disease↗
PubMed2002

Calcium channel mutations and migraine.

An increasing number of mutations in the CACNA1A gene have been identified, which are associated with a broad clinical spectrum, including familial hemiplegic migraine. Transfection studies and mouse model analyses are currently being undertaken to study the correlation between CACNA1A mutations and disease.

Animals↗
PubMed2002

Subcortical lacunar lesions: an MR imaging finding in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

PURPOSE: To assess the prevalence and distribution of subcortical lacunar lesions (SLLs) in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), to determine whether SLLs are an abnormal finding by studying their prevalence in healthy subjects, and to assess whether SLLs occur in other conditions associated with small vessel disease and white matter areas of high signal intensity (WMH). MATERIALS AND METHODS: The presence of SLLs, their location, and their relation to other abnormalities were assessed on magnetic resonance (MR) images (T1-weighted, T2-weighted, and fluid-attenuated inversion-recovery) obtained in 34 CADASIL patients and 20 healthy family members. Three additional control groups of healthy volunteers, elderly patients with vascular risk factors, and patients with another hereditary small vessel disease were also screened for the presence and location of SLLs. Sensitivity and specificity of the presence of SLLs for the diagnosis of CADASIL were assessed. RESULTS: SLLs were found in 20 (59%) of CADASIL patients. Incidence of SLLs increased with age (20%, <30 years; 50%, 30-50 years; 80%, >50 years). SLLs invariably occurred in the anterior temporal lobes and in areas where diffuse WMH expanded into arcuate fibers. From the anterior temporal lobe, the lesions could extend dorsally into the temporal lobes and rostrally into the frontal lobes. Lesions were not found in the parietal and occipital lobes. None of the control subjects had SLLs. Specificity and sensitivity of SLLs for CADASIL were 100% and 59%, respectively. CONCLUSION: SLLs are an abnormal finding at MR imaging that frequently occur in CADASIL patients.

Adult↗
PubMed1991

Efficacy of ICS 205-930, a novel 5-hydroxytryptamine3 (5-HT3) receptor antagonist, in the prevention of migraine attacks. A complex answer to a simple question. ICS 205-930 Migraine Study Group.

To investigate whether the novel, potent and highly selective 5-hydroxytryptamine3 (5-HT3) receptor antagonist ICS 205-930 can prevent migraine attacks, we conducted simultaneously two randomized, double-blind, placebo-controlled, multicentre, international trials, involving a total of 204 patients, suffering from classic or common migraine. Both trials had the same parallel-group design (1 month baseline observation, followed by 3 months treatment) and both produced remarkably similar results. The primary efficacy parameter was the proportional reduction in attack frequency recorded after 3 months of treatment. Twenty-two patients withdrew prematurely from the trials and could not be assessed for efficacy. Mild to severe constipation was reported by about 50% of the patients on active treatment. None of the doses of ICS 205-930 tested (50 mg, 25 mg and 15 mg daily) produced a statistically significantly better result to reduce attack frequency than did placebo. However, confidence intervals for the difference in effect with placebo were wide, indicating that 15 mg ICS 205-930 may produce a 57% reduction in attack frequency as compared to placebo. The most unusual finding was that, for all efficacy parameters, the best results were obtained with the lowest dose (15 mg), the worst results with the highest dose (50 mg) and an intermediate effect with 25 mg. Such an inverse relation between dose and efficacy suggests a bell-shaped dose-response curve, implying that doses lower than 15 mg might well prove to be more effective. Thus, the present study has produced inconclusive, but intriguing results. Lower doses should be further investigated before drawing any definite conclusion on the efficacy of ICS 205-930 in the prophylactic treatment of migraine.

Adolescent↗