A5078397461- Functional Brain Connectivity Studies
- Advanced Neuroimaging Techniques and Applications
- Dementia and Cognitive Impairment Research
- Advanced MRI Techniques and Applications
- Alzheimer's disease research and treatments
- Neuroscience and Neuropharmacology Research
- Health, Environment, Cognitive Aging
- Memory and Neural Mechanisms
- Histone Deacetylase Inhibitors Research
- Neuroinflammation and Neurodegeneration Mechanisms
- Cardiovascular Health and Disease Prevention
- Cellular transport and secretion
- Growth Hormone and Insulin-like Growth Factors
- Brain Tumor Detection and Classification
- Pituitary Gland Disorders and Treatments
- Retinal Development and Disorders
- Neurological and metabolic disorders
- Parkinson's Disease Mechanisms and Treatments
- Epigenetics and DNA Methylation
- Neurobiology and Insect Physiology Research
- Neurological disorders and treatments
- Frailty in Older Adults
- Nutritional Studies and Diet
- Neurological Disease Mechanisms and Treatments
- Diet and metabolism studies
Douglas Mental Health University Institute
2019-2025
McGill University
2018-2025
Alzheimer’s Disease Neuroimaging Initiative
2022
Abstract While numerous studies have used magnetic resonance imaging (MRI) to elucidate normative age‐related trajectories in subcortical structures across the human lifespan, there exists substantial heterogeneity among different studies. Here, we investigated relationships between age and morphology (i.e., volume shape), microstructure (using T1‐weighted/T2‐weighted [T1w/T2w] signal ratio as a putative index of myelin microstructure) striatum, globus pallidus, thalamus adult lifespan using...
Abstract Alzheimer’s disease (AD) is characterized by the brain accumulation of amyloid-β and tau proteins. A growing body literature suggests that epigenetic dysregulations play a role in interplay hallmark proteinopathies with neurodegeneration cognitive impairment. Here, we aim to characterize an dysregulation associated deposition Using positron emission tomography (PET) tracers selective for amyloid-β, tau, class I histone deacetylase (HDAC isoforms 1–3), find HDAC levels are reduced...
Abstract Alzheimer's disease is associated with pre-symptomatic changes in brain morphometry and accumulation of abnormal tau amyloid-beta pathology. Studying the development prior to symptoms onset may lead early diagnostic biomarkers a better understanding pathophysiology. pathology thought arise from combination protein spreading via neural connections, but how these processes influence atrophy progression phases remains unclear. Individuals family history (FHAD) have an elevated risk...
The hippocampus has been extensively studied in various neuropsychiatric disorders throughout the lifespan. However, inconsistent results have reported with respect to which subfield volumes are most related age. Here, we investigate whether these discrepancies may be explained by experimental design differences that exist between studies. Multiple datasets were used collect 1690 magnetic resonance scans from healthy individuals aged 18–95 years old. Standard T1-weighted (T1w; MPRAGE...
The study of the hippocampus across healthy adult lifespan has rendered inconsistent findings. While volumetric measurements have often been a popular technique for analysis, more advanced morphometric techniques demonstrated compelling results that highlight importance and improved specificity shape-based measures. Here, MAGeT Brain algorithm was applied on 134 individuals aged 18–81 years old to extract hippocampal subfield volumes shape measurements, namely: local surface area (SA)...
Statistical effects of cortical metrics derived from standard T1- and T2-weighted magnetic resonance imaging (MRI) images, such as gray-white matter contrast (GWC), boundary sharpness coefficient (BSC), T1-weighted/T2-weighted ratio (T1w/T2w), thickness (CT), are often interpreted representing or being influenced by intracortical myelin content with little empirical evidence to justify these interpretations. We first examined spatial correspondence more biologically specific microstructural...
White matter hyperintensities are radiological abnormalities reflecting cerebrovascular dysfunction detectable using MRI. often present in individuals at the later stages of lifespan and prodromal Alzheimer's disease spectrum. Tissue alterations underlying white may include demyelination, inflammation oedema, but these highly variable by neuroanatomical location between individuals. There is a crucial need to characterize hyperintensity tissue vivo improve prognosis and, potentially,...
Retrograde signaling is essential for neuronal growth, function and survival; however, we know little about how endosomes might be directed from synaptic terminals onto retrograde axonal pathways. We have identified Khc-73, a plus-end microtubule motor protein, as regulator of sorting in Drosophila larval neurons. The number boutons the amount neurotransmitter release at Khc-73 mutant neuromuscular junction (NMJ) are normal, but find significant decrease presynaptic sites. This defect larvae...
Abstract White matter hyperintensities (WMHs) are clinically significant MRI abnormalities often detected in the elderly and early stages of Alzheimer’s Disease. They indicative vascular pathology but represent a mixture microstructural tissue alterations that is highly variable between individuals. To better understand these alterations, we leveraged signal different contrasts sampled within WMHs, which have differential sensitivity to properties. Subsequently, sought examine asso WMH...
Alzheimer's disease (AD) is primarily characterized by the accumulation of amyloid and tau pathologies. However, alterations in detailed organization composition neural tissue also contribute to disease's early stages. Here, we sought explore whether hippocampal cortical microstructural changes, such as myelin inflammation-mediated increases iron, could serve indices AD-related pathophysiology. In this study, included 158 participants across AD spectrum: from individuals without cognitive...
Abstract The hippocampus has been extensively studied in various neuropsychiatric disorders throughout the lifespan. However, inconsistent results have reported with respect to which subfield volumes are most related age. Here, we investigate whether these discrepancies may be explained by experimental design differences that exist between studies. Multiple datasets were used collect 1690 magnetic resonance scans from healthy individuals aged 18-95 years old. Standard T1-weighted (T1w;...
Morphometric and quantitative MRI metrics have rarely been used simultaneously to characterize healthy aging Alzheimer’s disease (AD) progression. Here, cortical vertex-wise hippocampal voxel-wise were extracted infer atrophy progression (using thickness, surface area or relative Jacobians), myelin iron contents (T1 T2* respectively). A data-driven approach was parcellate the cortex hippocampus. multivariate statistical technique link demographics cognitive scores of interest. Our results...
Abstract The study of the hippocampus across healthy adult lifespan has rendered inconsistent findings. While volumetric measurements have often been a popular technique for analysis, more advanced morphometric techniques demonstrated compelling results that highlight importance and improved specificity shape-based measures. Here, MAGeT Brain algorithm was applied on 134 individuals aged 18-81 years old to extract hippocampal subfield volumes shape measurements, notably: local surface area...
Abstract Background Although several volumetric studies have attempted to examine the relationship between hippocampal subfields and age, their findings are heterogenous. Here, in addition typical measures, we investigated age‐related alterations of subfield shape microstructure. Method The present work included 161 healthy participants (ages 18‐81) recruited as part two local datasets. Standard T1‐weighted (T1w; MPRAGE sequence, 1 mm3 voxels) high‐resolution T2‐weighted (T2w, 0.64 magnetic...
Abstract Cortical thickness (CT), gray-white matter contrast (GWC), boundary sharpness coefficient (BSC), and T1-weighted/T2-weighted ratio (T1w/T2w) are cortical metrics derived from standard T1- T2-weighted magnetic resonance imaging (MRI) images that often interpreted as representing or being influenced by intracortical myelin content. However, there is little empirical evidence to justify these interpretations nor have the homologies differences between measures been examined. We...
Morphometric and quantitative magnetic resonance imaging techniques have rarely been used simultaneously to characterise healthy aging Alzheimer’s disease (AD) progression. Here, we are extracting four vertex-wise cortical metrics : thickness, surface area, T1 value (myelin) T2* values (iron). All these were analysed using non-negative matrix factorization linear models. Overall, thinning seemed be linked both AD progression, while decrease in myelin a phenomenon mostly related...