Your search for: 'author:("Hyman, Bradley T.")' has returned 5 results. (0.011s) Save search

Authors: Noori, Ayush | Jayakumar, Rojashree | Moturi, Vaishnavi | Li, Zhaozhi | Liu, Rongxin | Serrano-Pozo, Alberto | Hyman, Bradley T. | Das, Sudeshna

Article Type: Research Article

Abstract: Background: Recent Alzheimer’s disease (AD) discoveries are increasingly based on studies from a variety of omics technologies on large cohorts. Currently, there is no easily accessible resource for neuroscientists to browse, query, and visualize these complex datasets in a harmonized manner. Objective: Create an online portal of public omics datasets for AD research. Methods: We developed Alzheimer DataLENS, a web-based portal, using the R Shiny platform to query and visualize publicly available transcriptomics and genetics studies of AD on human cohorts. To ensure consistent representation of AD findings, all datasets were processed through a uniform bioinformatics pipeline. Results: Alzheimer DataLENS …currently houses 2 single-nucleus RNA sequencing datasets, over 30 bulk RNA sequencing datasets from 19 brain regions and 3 cohorts, and 2 genome-wide association studies (GWAS). Available visualizations for single-nucleus data include bubble plots, heatmaps, and UMAP plots; for bulk expression data include box plots and heatmaps; for pathways include protein-protein interaction network plots; and for GWAS results include Manhattan plots. Alzheimer DataLENS also links to two other knowledge resources: the AD Progression Atlas and the Astrocyte Atlas. Conclusions: Alzheimer DataLENS is a valuable resource for investigators to quickly and systematically explore omics datasets and is freely accessible at https://alzdatalens.partners.org . Show more

Keywords: Alzheimer’s disease, database, genetics, multiomics, single-cell RNA-seq, transcriptomics

DOI: 10.3233/JAD-230884

Citation: Journal of Alzheimer's Disease, vol. 99, no. s2, pp. S397-S407, 2024

Authors: Mezlini, Aziz M. | Magdamo, Colin | Merrill, Emily | Chibnik, Lori B. | Blacker, Deborah L. | Hyman, Bradley T. | Das, Sudeshna

Article Type: Research Article

Abstract: Background: The APOE ɛ 4 allele is the largest genetic risk factor for late-onset Alzheimer’s disease (AD). Recent literature suggested that the contribution of APOE ɛ 4 to AD risk could be population-specific, with ɛ 4 conferring a lower risk to Blacks or African Americans. Objective: To investigate the effect of APOE haplotypes on AD risk in individuals with European ancestry (EU) and Blacks or African Americans (AA). Methods: We selected data from 1) the National Alzheimer’s Coordinating Center: a total of 3,486 AD cases and 4,511 controls (N = 7,997, 60% female) with genotypes from the Alzheimer’s Disease Genetics Consortium (ADGC), …and 2) the Rush University Religious Orders Study and Memory and Aging Project (ROSMAP) cohort with 578 AD and 670 controls (N = 1,248, 60% female). Using ɛ 3 homozygotes as the reference, we compared the association of various APOE haplotypes with the clinical and neuropathological correlates of dementia in AA and EU. Results: In both cohorts, we find no difference in the odds or age of onset of AD among the ɛ 4-linked haplotypes defined by rs769449 within either AA or EU. Additionally, while APOE ɛ 4 was associated with a faster rate of decline, no differences were found in rate of decline, clinical or neuropathological features among the ɛ 4-linked haplotypes. Further analysis with other variants near the APOE locus failed to identify any effect modification. Conclusion: Our study finds similar effects of the ɛ 4-linked haplotypes defined by rs769449 on AD as compared to ɛ 3 in both AA and EU. Future studies are required to understand the heterogeneity of APOE conferred risk of AD among various genotypes and populations. Show more

Keywords: African Americans, APOE, clinicopathological features, Europeans, genotype

DOI: 10.3233/JAD-200228

Citation: Journal of Alzheimer's Disease, vol. 78, no. 1, pp. 467-477, 2020

Authors: Bakshi, Rachit | Macklin, Eric A. | Hung, Albert Y. | Hayes, Michael T. | Hyman, Bradley T. | Wills, Anne-Marie | Gomperts, Stephen N. | Growdon, John H. | Ascherio, Alberto | Scherzer, Clemens R. | Schwarzschild, Michael A.

Article Type: Short Communication

Abstract: Two purines, caffeine and urate, have been associated with a reduced risk of idiopathic Parkinson’s disease (PD) in multiple cohorts and populations. The Harvard Biomarkers Study (HBS) is a longitudinal study designed to accelerate the discovery and validation of molecular diagnostic and progression markers of early-stage PD. To investigate whether these ‘reduced risk’ factors are associated with PD within this cohort, we conducted a cross-sectional, case-control study in 566 subjects consisting of idiopathic PD patients and healthy controls. Caffeine intake as assessed by a validated questionnaire was significantly lower in idiopathic PD patients compared to healthy controls in males (mean …difference –125 mg/day, p  < 0.001) but not in females (mean difference –30 mg/day, p  = 0.29). A strong inverse association was also observed with plasma urate levels both in males (mean difference –0.46 mg/dL, p  = 0.017) and females (mean difference –0.45 mg/dL, p  = 0.001). Both analyses stratified for sex and adjusted for age, body mass index, and either urate level or caffeine consumption, respectively. These results highlight the robustness of caffeine intake and urate as factors inversely associated with idiopathic PD. Show more

Keywords: Caffeine, uric acid, biomarker, Parkinson’s disease

DOI: 10.3233/JPD-191882

Citation: Journal of Parkinson's Disease, vol. 10, no. 2, pp. 505-510, 2020

Authors: Dumurgier, Julien | Hanseeuw, Bernard J. | Hatling, Frances B. | Judge, Kelly A. | Schultz, Aaron P. | Chhatwal, Jasmeer P. | Blacker, Deborah | Sperling, Reisa A. | Johnson, Keith A. | Hyman, Bradley T. | Gómez-Isla, Teresa

Article Type: Research Article

Abstract: Background: Identifying older adults at risk of cognitive decline represents a challenge as Alzheimer’s disease (AD) modifying therapies move toward preclinical stages. Objective: To investigate the relationship between AD biomarkers and subsequent change in cognition in a cohort of cognitively intact older adults. Methods: 84 cognitively normal subjects (mean age 72.0 years, 59% women) were recruited through the Massachusetts Alzheimer’s Disease Research Center and the Harvard Aging Brain Study and followed over 3 years. Measurements of amyloid-β 1–42 (Aβ42 ), total Tau (t-Tau), and Tau phosphorylated at threonine 181 (p-Tau181) in the cerebrospinal fluid (CSF) at study entry were available …in all cases. Baseline brain MRI, FDG-PET, and PiB-PET data were available in the majority of participants. Relationship between baseline AD biomarkers and longitudinal change in cognition was assessed using Cox proportional hazard regression and linear mixed models. Results: 14% participants increased their global Clinical Dementia Rating (CDR) score from 0 to 0.5 during follow-up. A CDR score increase was associated with higher baseline CSF t-Tau and p-Tau181, higher global cortical PiB retention, and lower hippocampal volume. The combination of high CSF t-Tau and low Aβ42 or low hippocampal volume was more strongly related to cognitive outcome than each single biomarker. Higher CSF t-Tau was the only biomarker associated with subsequent decline in MMSE score. Conclusions: Baseline CSF t-Tau and p-Tau181, in vivo amyloid load, and hippocampal volume were all independently associated with future decline in cognition. The discriminatory ability of these biomarkers to predict risk of cognitive decline, however, was only modest. Show more

Keywords: Biomarkers, cognitive decline, cerebrospinal fluid, epidemiology, neuroimaging

DOI: 10.3233/JAD-170511

Citation: Journal of Alzheimer's Disease, vol. 60, no. 4, pp. 1451-1459, 2017

Authors: Petrozziello, Tiziana | Huntress, Sommer S. | Castillo-Torres, Ayleen L. | Quinn, James P. | Connors, Theresa R. | Auger, Corinne A. | Mills, Alexandra N. | Kim, Spencer E. | Liu, Sophia | Mahmood, Farah | Boudi, Adel | Wu, Muzhou | Sapp, Ellen | Kivisäkk, Pia | Sunderesh, Shekar R. | Pouladi, Mahmoud A. | Arnold, Steven E. | Hyman, Bradley T. | Rosas, H. Diana | DiFiglia, Marian | Mouro Pinto, Ricardo | Kegel-Gleason, Kimberly | Sadri-Vakili, Ghazaleh

Article Type: Research Article

Abstract: Background: To date, it is still controversial whether tau phosphorylation plays a role in Huntington’s disease (HD), as previous studies demonstrated either no alterations or increases in phosphorylated tau (pTau) in HD postmortem brain and mouse models. Objective: The goal of this study was to determine whether total tau and pTau levels are altered in HD. Methods: Immunohistochemistry, cellular fractionations, and western blots were used to measure total tau and pTau levels in a large cohort of HD and control postmortem prefrontal cortex (PFC). Furthermore, western blots were performed to assess tau, and pTau levels in HD and control isogenic …embryonic stem cell (ESC)-derived cortical neurons and neuronal stem cells (NSCs). Similarly, western blots were used to assess tau and pTau levels in HttQ 111 and transgenic R6/2 mice. Lastly, total tau levels were assessed in HD and healthy control plasma using Quanterix Simoa assay. Results: Our results revealed that, while there was no difference in total tau or pTau levels in HD PFC compared to controls, the levels of tau phosphorylated at S396 were increased in PFC samples from HD patients 60 years or older at time of death. Additionally, tau and pTau levels were not changed in HD ESC-derived cortical neurons and NSCs. Similarly, total tau or pTau levels were not altered in HttQ 111 and transgenic R6/2 mice compared to wild-type littermates. Lastly, tau levels were not changed in plasma from a small cohort of HD patients compared to controls. Conclusions: Together these findings demonstrate that pTau-S396 levels increase significantly with age in HD PFC. Show more

Keywords: Huntington’s disease, total tau, phosphorylated tau, fractionations, postmortem brain, ESC-derived neurons, neuronal stem cells, mouse models, plasma

DOI: 10.3233/JHD-230588

Citation: Journal of Huntington's Disease, vol. 12, no. 3, pp. 267-281, 2023