Publications by authors named "Luke Bonham"

Cross-sectional studies suggest a limited relationship between accelerated epigenetic aging derived from epigenetic clocks, and Alzheimer's disease (AD) pathophysiology or risk. However, most prior analyses have not utilized longitudinal analyses or whole-brain neuroimaging biomarkers of AD. Herein, we employed longitudinal modeling and structural neuroimaging analyses to test the hypothesis that accelerated epigenetic aging would predict AD progression.

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  • Recent transcriptomics studies show increased interferon (IFN) responses in various neurodegenerative diseases such as Alzheimer's and Parkinson's, highlighting these responses in both microglia and T cells.
  • The literature indicates that abnormal IFN signaling is also linked to neuropsychiatric disorders like major depression and PTSD.
  • This review aims to summarize findings about IFN responses in neurodegeneration, discuss how sex and ancestry influence these responses, and explore potential reasons for elevated antiviral IFN signaling in neurological and psychiatric conditions without viral involvement.
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  • In frontotemporal lobar degeneration (FTLD), abnormal protein buildup in the brain correlates with declines in social-emotional and language skills, primarily involving TDP-43 or tau proteins.
  • The study investigates how degeneration patterns in FTLD relate to gene expression of recently evolved genetic regions, using neuroimaging and transcriptomic data to examine targeted brain areas.
  • Results indicate that FTLD subtypes uniquely or overlappingly affect brain regions tied to genes evolved in humans, with a notable relationship between TDP-43 function impairment and cryptic splicing in affected genes.
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Introduction: Altered immune signatures are emerging as a central theme in neurodegenerative disease, yet little is known about immune responses in early-onset Alzheimer's disease (EOAD).

Methods: We examined single-cell RNA-sequencing (scRNA-seq) data from peripheral blood mononuclear cells (PBMCs) and droplet digital polymerase chain reaction (ddPCR) data from CD4 T cells from participants with EOAD and clinically normal controls.

Results: We analyzed PBMCs from 16 individuals by scRNA-seq and discovered increased interferon signaling-associated gene (ISAG) expression and striking expansion of antiviral-like ISAG T cells in EOAD.

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Introduction: A hexanucleotide repeat expansion (HRE) intronic to chromosome 9 open reading frame 72 () is recognized as the most common genetic cause of amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and ALS-FTD. Identifying genes that show similar regional co-expression patterns to may help identify novel gene targets and biological mechanisms that mediate selective vulnerability to ALS and FTD pathogenesis.

Methods: We leveraged mRNA expression data in healthy brain from the Allen Human Brain Atlas to evaluate co-expression patterns.

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  • Frontotemporal lobar degeneration (FTLD) is a disease that affects how people think and communicate, causing issues in emotions and language.
  • Researchers studied brain regions affected by FTLD to see if they are linked to special human genes that have changed through evolution.
  • They found that certain genes related to brain functions are targeted by different types of FTLD, suggesting that this disease hits parts of the brain that have recently evolved to help humans.
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Introduction: Altered immune signatures are emerging as a central theme in neurodegenerative disease, yet little is known about immune responses in early-onset Alzheimer's disease (EOAD).

Methods: We examined single-cell RNA-sequencing (scRNA-seq) data from peripheral blood mononuclear cells (PBMCs) and droplet digital (dd)PCR data from CD4 T cells from participants with EOAD and clinically normal controls.

Results: We analyzed ~182,000 PBMCs by scRNA-seq and discovered increased interferon signaling-associated gene (ISAG) expression and striking expansion of antiviral-like ISAG T cells in EOAD.

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  • * A study applied a polygenic hazard score to early-onset AD patients and found that their scores were similar to those of late-onset patients, suggesting that genetic factors associated with late-onset AD do not explain early-onset cases.
  • * The research indicates that early-onset AD has a distinct genetic makeup compared to late-onset AD, highlighting the need for further investigation into unique genetic factors related to early-onset AD.
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Introduction: A hexanucleotide repeat expansion (HRE) intronic to chromosome 9 open reading frame 72 () is recognized as the most common genetic cause of amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and ALS-FTD. Identifying genes that show similar regional co-expression patterns to may help identify novel gene targets and biological mechanisms that mediate selective vulnerability to ALS and FTD pathogenesis.

Methods: We leveraged mRNA expression data in healthy brain from the Allen Human Brain Atlas to evaluate co-expression patterns.

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Background: Emerging evidence from mouse models is beginning to elucidate the brain's immune response to tau pathology, but little is known about the nature of this response in humans. In addition, it remains unclear to what extent tau pathology and the local inflammatory response within the brain influence the broader immune system.

Methods: To address these questions, we performed single-cell RNA sequencing (scRNA-seq) of peripheral blood mononuclear cells (PBMCs) from carriers of pathogenic variants in MAPT, the gene encoding tau (n = 8), and healthy non-carrier controls (n = 8).

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Prcis: Optical coherence tomography (OCT) estimated retinal nerve fiber layer (RNFL) thickness associated with glaucoma-related disability independent of the visual field (VF) damage and thus may provide additional patient-relevant disability information beyond what is captured by standard VF testing.

Purpose: To examine whether OCT metrics [peripapillary RNFL thickness and macular ganglion cell/inner plexiform layer (GCIPL) thickness] are associated with quality of life (QoL) measures and additional disability metrics, and whether these associations are independent of VF damage.

Methods: In this cross-sectional study, 156 patients with glaucoma or suspected glaucoma received VF testing and OCT scans to measure RNFL and GCIPL thickness.

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  • The study investigates the relationship between visual artistic creativity (VAC) and frontotemporal dementia (FTD), suggesting that VAC can emerge early in FTD and may be linked to changes in the dorsomedial occipital cortex.
  • A total of 689 FTD patients were analyzed, with 17 showing VAC, and their data were compared with two control groups to understand the neuroanatomical and physiological basis of VAC in FTD.
  • Results highlighted that VAC often coincides with the onset of FTD symptoms and is associated with specific brain atrophy patterns, particularly in the dorsomedial occipital region, which may play a role in visual creative processes.
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  • Frontotemporal dementia (FTD) has unclear genetic reasons for its impact on certain brain regions, prompting researchers to analyze data from genome-wide association studies (GWAS) to find genetic links between FTD and brain structure.
  • The study found five brain regions strongly correlated with FTD risk and identified eight relevant protein-coding genes, indicating shared genetic underpinnings.
  • Additionally, the research revealed that the N-ethylmaleimide sensitive factor (NSF) gene's expression decreases with age in a mouse model, suggesting its significance in understanding FTD's etiology.
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Hexanucleotide repeat expansion (HRE) within is the most common genetic cause of frontotemporal dementia (FTD). Thalamic atrophy occurs in both sporadic and familial FTD but is thought to distinctly affect HRE carriers. Separately, emerging evidence suggests widespread derepression of transposable elements (TEs) in the brain in several neurodegenerative diseases, including HRE-mediated FTD (C9-FTD).

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-related leukoencephalopathy is an autosomal dominant neurodegenerative disease caused by mutations in the tyrosine kinase domain of the colony stimulating factor 1 receptor (CSF1R). Several studies have found that hematogenic stem cell transplantation is an effective disease modifying therapy however the literature regarding prodromal and early symptoms -related leukoencephalopathy is limited. We describe a 63-year-old patient with 4 years of repetitive scratching and skin picking behavior followed by 10 years of progressive behavioral, cognitive, and motor decline in a pattern suggesting behavioral variant of frontotemporal dementia.

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Early-onset Alzheimer's disease (EOAD) is a rare but particularly devastating form of AD. Though notable for its high degree of clinical heterogeneity, EOAD is defined by the same neuropathological hallmarks underlying the more common, late-onset form of AD. In this review, we describe the various clinical syndromes associated with EOAD, including the typical amnestic phenotype as well as atypical variants affecting visuospatial, language, executive, behavioral, and motor functions.

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Microglia play a critical but poorly understood role in promoting white-matter homeostasis. In this review, we leverage advances in human genetics and mouse models of leukodystrophies to delineate our current knowledge and identify outstanding questions regarding the impact of microglia on central nervous system white matter. We first focus on the role of pathogenic mutations in genes, such as , and that cause leukodystrophies in which the primary deficit is thought to originate in microglia.

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  • Men with Alzheimer's disease typically die earlier and show more cognitive deficits compared to women, indicating a significant sex difference in the disease's impact.
  • Research on genetically modified mice demonstrated that the presence of a second X chromosome provides protective effects against mortality and cognitive deficits associated with Alzheimer's.
  • The study indicates that specific genes on the X chromosome may play a role in resilience against Alzheimer's, hinting at the importance of considering sex chromosomes in understanding disease vulnerability.
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Injury to the pudendal nerve in men presents with pain, paresthesia, or numbness of the perineum, and/or scrotum, and/or penis. There is evidence implicating the brachytherapy seeds used to treat prostate cancer as source of pudendal nerve injury. Compared to surgical prostatectomy, brachytherapy has the advantage of being less invasive, but seeds may not only lead to well-established complications such as urinary, bowel, and erectile dysfunction, but also injury to the sensory branches of the pudendal nerve.

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Objectives: The aim of this study was to test the hypothesis that clinically used magnetic resonance (MR)-conditional needles of varying lengths, orientations, locations, and pulse sequences can result in excessive heating during MR imaging (MRI)-guided interventions that can be minimized to physiological ranges with proper selection of the needle length, needle position, and modification of pulse sequence parameters.

Materials And Methods: We simulated a clinical interventional MRI setting with 2 standard American Society for Testing and Materials F2182-11A phantoms and measured temperatures with fiber optic sensors. Temperature profiles were monitored for commercial 10, 15 and 20 cm MR-conditional cobalt-chromium needles in clinically relevant perpendicular, 45-degree oblique, and parallel orientations relative to the static magnetic field (B0) and center, right off-center, and left off-center needle tip locations in the z = 0 plane.

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We conducted genome sequencing to search for rare variation contributing to early-onset Alzheimer's disease (EOAD) and frontotemporal dementia (FTD). Discovery analysis was conducted on 435 cases and 671 controls of European ancestry. Burden testing for rare variation associated with disease was conducted using filters based on variant rarity (less than one in 10,000 or private), computational prediction of deleteriousness (CADD) (10 or 15 thresholds), and molecular function (protein loss-of-function [LoF] only, coding alteration only, or coding plus non-coding variants in experimentally predicted regulatory regions).

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To date, patient motivations for Asian blepharoplasty and the surgery's impact on quality of life have not been quantified. Here, we employed structured interviews and a web-based survey to better characterize patient motivations for Asian blepharoplasty and the impact of Asian blepharoplasty on self-reported domains of happiness, self-esteem, attractiveness, social life, and professional life. Structured interviews were conducted to inform a web-based survey regarding Asian blepharoplasty.

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Radiogenomics, defined as the integrated analysis of radiologic imaging and genetic data, is a well-established tool shown to augment neuroimaging in the clinical diagnosis, prognostication, and scientific study of late-onset Alzheimer disease (LOAD). Early work using candidate single nucleotide polymorphisms (SNPs) identified genetic variation in APOE, BIN1, CLU, and CR1 as key modifiers of brain structure and function using magnetic resonance imaging (MRI). More recently, polygenic risk scores used in conjunction with MRI and positron emission tomography have shown great promise as a risk-stratification tool for clinical trials and care-management decisions.

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Purpose Of Review: In this review we highlight recent advances in the human genetics of frontotemporal dementia (FTD). In addition to providing a broad survey of genes implicated in FTD in the last several years, we also discuss variation in genes implicated in both hereditary leukodystrophies and risk for FTD (e.g.

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Purpose: To assess the impact of OCT signal strength (SS) and artifact on retinal nerve fiber layer (RNFL) measurement reliability and to understand whether glaucoma severity modifies this relationship.

Design: Retrospective, longitudinal cohort study.

Participants: Two thousand nine hundred ninety-two OCT scans from 474 eyes of 241 patients with glaucoma or glaucoma suspect status.

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