412 results match your criteria: "Montreal Neurological Institute Hospital[Affiliation]"

Essential Tremor (ET) is the most common movement disorder and has a worldwide prevalence of 1%, including 5% of the population over 65 years old. It is characterized by an active, postural or kinetic tremor, primarily affecting the upper limbs, and is diagnosed based on clinical characteristics. The pathological mechanisms of ET, however, are mostly unknown.

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Modulation of in vitro Network Activity by Optogenetic Stimulation of Parvalbumin-positive Interneurons During Estrous Cycle.

Curr Neuropharmacol

January 2025

Departments of Neurology & Neurosurgery, and Physiology, Montreal Neurological Institute-Hospital, McGill University, 3801 University Street, Montréal, Québec, H3A 2B4, Canada.

Background: Catamenial epilepsy, which is defined as a periodicity of seizure exacerbation occurring during the menstrual cycle, has been reported in up to 70% of epileptic women. These seizures are often non-responsive to medication and our understanding of the relation between menstrual cycle and seizure generation (i.e.

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The anti-dyskinetic effect of the clinic-ready mGluRpositive allosteric modulator AZD8529 in the 6-OHDA-lesioned rat.

Naunyn Schmiedebergs Arch Pharmacol

January 2025

Neurodegenerative Disorders Research Group, Montreal Neurological Institute-Hospital (The Neuro), 3801 University St, Montreal, QC, H3A 2B4, Canada.

L-3,4-dihydroxyphenylalanine (L-DOPA) remains the main treatment for motor symptoms of Parkinson's disease (PD). However, chronic use is associated with the development of complications such as L-DOPA-induced dyskinesia. We previously demonstrated that LY-487,379, a highly selective metabotropic glutamate receptor 2 (mGluR2) positive allosteric modulator (PAM), reduces the severity of L-DOPA-induced abnormal involuntary movements (AIMs) in the 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD, without interfering with the anti-parkinsonian action of L-DOPA.

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Objectives: To analyze sex differences in outcomes in Tourette syndrome (TS) and Persistent Motor or Vocal tic disorders (PMVT) in the Tourette Association of America International Consortium for Genetics (TAAICG) dataset.

Methods: The relationship between sex and clinical measures was explored in 2,403 participants (N = 2,109 with TS; N = 294 with PMVT) from the TAAICG dataset using generalized estimating equation regression models, and adjusted for age and family relationships.

Results: Female (vs male) participants with TS (25.

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Malignant gliomas are heterogeneous tumors, mostly incurable, arising in the central nervous system (CNS) driven by genetic, epigenetic, and metabolic aberrations. Mutations in isocitrate dehydrogenase (IDH1/2) enzymes are predominantly found in low-grade gliomas and secondary high-grade gliomas, with IDH1 mutations being more prevalent. Mutant-IDH1/2 confers a gain-of-function activity that favors the conversion of a-ketoglutarate (α-KG) to the oncometabolite 2-hydroxyglutarate (2-HG), resulting in an aberrant hypermethylation phenotype.

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Movie-watching is a central aspect of our lives and an important paradigm for understanding the brain mechanisms behind cognition as it occurs in daily life. Contemporary views of ongoing thought argue that the ability to make sense of events in the 'here and now' depend on the neural processing of incoming sensory information by auditory and visual cortex, which are kept in check by systems in association cortex. However, we currently lack an understanding of how patterns of ongoing thoughts map onto the different brain systems when we watch a film, partly because methods of sampling experience disrupt the dynamics of brain activity and the experience of movie-watching.

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Blood-based biomarkers for Alzheimer's disease (AD) pathology have been intensively investigated as markers for AD-related neurodegeneration. Comorbid AD pathology is common in dementia with Lewy bodies (DLB). Accordingly, we hypothesized that plasma biomarkers associated with AD pathology might be useful to predict DLB in a cohort of idiopathic/isolated REM sleep behavior disorder (iRBD), an incipient synucleinopathy.

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EEFSEC deficiency: A selenopathy with early-onset neurodegeneration.

Am J Hum Genet

January 2025

Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany; Center for Rare Disease, University of Tübingen, 72076 Tübingen, Germany; Genomics for Health in Africa (GHA), Africa-Europe Cluster of Research Excellence (CoRE).

Inborn errors of selenoprotein expression arise from deleterious variants in genes encoding selenoproteins or selenoprotein biosynthetic factors, some of which are associated with neurodegenerative disorders. This study shows that bi-allelic selenocysteine tRNA-specific eukaryotic elongation factor (EEFSEC) variants cause selenoprotein deficiency, leading to progressive neurodegeneration. EEFSEC deficiency, an autosomal recessive disorder, manifests with global developmental delay, progressive spasticity, ataxia, and seizures.

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Fast activity chirp patterns in focal seizures from patients and animal models.

Epilepsia

December 2024

Epilepsy Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Istituto Neurologico Carlo Besta, Milan, Italy.

Time-frequency analysis of focal seizure electroencephalographic signals performed with depth electrodes in human temporal lobe structures has revealed the occurrence at onset of oscillations at approximately 30-100 Hz that feature a monotonic rapid decay in frequency content. This seizure onset pattern, referred to as chirp, has been identified as a highly specific and sensitive marker of focal seizures that are characterized by low-voltage fast activity. We report that this chirp pattern is also observed in animal models of temporal lobe epilepsy in both in vivo and in vitro preparations.

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Biallelic variants in GLDN have recently been associated with lethal congenital contracture syndrome 11 (LCCS11), a form of fetal akinesia deformation sequence (FADS) with high neonatal mortality. In this report, we describe five individuals from two Canadian Inuit families originating from different communities in Nunavik all affected with FADS and harboring a rare homozygous missense variant, [NM_181789.4:c.

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Discovery of MDI-114215: A Potent and Selective LIMK Inhibitor To Treat Fragile X Syndrome.

J Med Chem

January 2025

Medicines Discovery Institute, School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K.

LIMKs are serine/threonine and tyrosine kinases responsible for controlling cytoskeletal dynamics as key regulators of actin stability, ensuring synaptic health through normal synaptic bouton structure and function. However, LIMK1 overactivation results in abnormal dendritic synaptic development that characterizes the pathogenesis of Fragile X Syndrome (FXS). As a result, the development of LIMK inhibitors represents an emerging disease-modifying therapeutic approach for FXS.

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Oculopharyngeal muscular dystrophy (OPMD) is a rare late-onset muscle disease with progressive dysphagia as a major symptom. The Dysphagiameter is a newly developed patient-reported outcome measure (PROM) to assess the severity of dysphagia and its impact in patients with OPMD. This article reports on item reduction and a first assessment of the Dysphagiameter's psychometrics properties, in a French and English-speaking population of individuals with OPMD.

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Genetic variants in DDX53 contribute to autism spectrum disorder associated with the Xp22.11 locus.

Am J Hum Genet

January 2025

The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; McLaughlin Centre, Toronto, ON M5G 0A4, Canada. Electronic address:

Autism spectrum disorder (ASD) exhibits an ∼4:1 male-to-female sex bias and is characterized by early-onset impairment of social/communication skills, restricted interests, and stereotyped behaviors. Disruption of the Xp22.11 locus has been associated with ASD in males.

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Background: Brain metastasis invasion pattern (BMIP) is an emerging biomarker associated with recurrence-free and overall survival in patients, and differential response to therapy in preclinical models. Currently, BMIP can only be determined from the histopathological examination of surgical specimens, precluding its use as a biomarker prior to therapy initiation. The aim of this study was to investigate the potential of machine learning (ML) approaches to develop a noninvasive magnetic resonance imaging (MRI)-based biomarker for BMIP determination.

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repeat expansion creates the unstable folate-sensitive fragile site FRA9A.

NAR Mol Med

October 2024

Program of Genetics and Genome Biology, Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, 686 Bay Street, Toronto, M5G 0A4, Canada.

The hyper-unstable Chr9p21 locus, harbouring the interferon gene cluster, oncogenes and , is linked to multiple diseases. (GGGGCC)n expansions (Exp) are associated with incompletely penetrant amyotrophic lateral sclerosis, frontotemporal dementia and autoimmune disorders. Exp patients display hyperactive cGAS-STING-linked interferon immune and DNA damage responses, but the source of immunostimulatory or damaged DNA is unknown.

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Target 2035 is a global initiative that seeks to identify a pharmacological modulator of most human proteins by the year 2035. As part of an ongoing series of annual updates of this initiative, we summarise here the efforts of the EUbOPEN project whose objectives and results are making a strong contribution to the goals of Target 2035. EUbOPEN is a public-private partnership with four pillars of activity: (1) chemogenomic library collections, (2) chemical probe discovery and technology development for hit-to-lead chemistry, (3) profiling of bioactive compounds in patient-derived disease assays, and (4) collection, storage and dissemination of project-wide data and reagents.

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The Parkinson's disease risk gene cathepsin B promotes fibrillar alpha-synuclein clearance, lysosomal function and glucocerebrosidase activity in dopaminergic neurons.

Mol Neurodegener

November 2024

Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, McGill Parkinson Program, Montreal Neurological Institute-Hospital, McGill University, Montreal, Québec, Canada.

Article Synopsis
  • - Variants in the CTSB gene are linked to an increased risk of Parkinson's disease (PD) and affect the activity of cathepsin B, an enzyme involved in breaking down proteins and regulating cellular processes related to autophagy and lysosome function.
  • - CatB can both degrade the harmful alpha-synuclein protein associated with PD and potentially create shorter versions of it that are more prone to aggregation, complicating its role in PD pathology.
  • - Experiments showed that inhibiting catB disrupts autophagy and lysosomal function, leading to an accumulation of toxic protein aggregates, while activating catB enhances the clearance of these aggregates in cell and neuron models.
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Article Synopsis
  • Parkinson's disease (PD) is a progressive movement disorder becoming more common due to an aging population, and researchers aimed to explore rare genetic variants that could help explain its development.
  • Whole-exome sequencing was conducted on a large group of PD cases and controls of Asian ancestry, revealing significant links between the genes GBA1 and SMPD1 and the risk of developing PD, confirmed in additional samples.
  • The research found that specific SMPD1 variants that reduced enzyme activity were particularly associated with PD risk, with a prominent Asian-specific variant being common among carriers.
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Homocysteine, neurodegenerative biomarkers, and APOE ε4 in neurodegenerative diseases.

Alzheimers Dement

November 2024

Department of Pharmacology & Toxicology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.

Introduction: Elevated plasma homocysteine (Hcy) is associated with an increased risk of developing neurodegenerative diseases; however, its relationship with the apolipoprotein E (APOE) ε4 allele has not been well characterized.

Methods: Participants clinically diagnosed with Alzheimer's disease or mild cognitive impairment (AD/MCI), frontotemporal dementia, Parkinson's disease, or cerebrovascular disease were stratified by the presence of the APOE ε4 allele. Volumetric magnetic resonance imaging, plasma amyloid/tau/neurodegeneration biomarkers, and cognitive performance were quantified.

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Background: The findings of variants of uncertain significance (VUS) on a clinical genetic testing report pose a challenge for attending healthcare professionals (HCPs) in patient care. Here, we describe the outcomes of multidisciplinary VUS Rounds, implemented at a neurological disease tertiary care centre, which aid in interpreting and communicating VUS identified in our neurogenetics patient population.

Methods: VUS Rounds brought together genetic counsellors, molecular geneticists and scientists to evaluate VUS against genomic and phenotypic evidence and assign an internal temperature classification of 'VUS Hot', 'True VUS' or 'VUS Cold', corresponding to potential pathogenicity.

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Genetic-based diagnostics of Parkinson's disease and other Parkinsonian syndromes.

Expert Rev Mol Diagn

November 2024

The Neuro (Montréal Neurological Institute-Hospital), McGill University, Montréal, Canada.

Article Synopsis
  • - Parkinson's disease (PD) is not a one-size-fits-all condition; it has various subtypes that may exhibit similar symptoms but could require different treatments due to different underlying causes.
  • - The review highlights numerous genes linked to PD, discussing their impact on age of onset, disease progression, and symptoms, and distinguishes PD from related disorders.
  • - Genetic screening could enhance diagnosis and prognosis for PD, aiding in treatment decisions and identifying candidates for clinical trials, though genetic studies alone can't definitively diagnose the disease.
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