Traumatic brain injury is a leading cause of chronic neurologic disability and a risk factor for development of neurodegenerative disease. However, little is known regarding the pathophysiology of human traumatic brain injury, especially in the window after acute injury and the later life development of progressive neurodegenerative disease. Given the proposed mechanisms of toxic protein production and neuroinflammation as possible initiators or contributors to progressive pathology, we examined phosphorylated tau accumulation, microgliosis and astrogliosis using immunostaining in the orbitofrontal cortex, a region often vulnerable across traumatic brain injury exposures, in an age and sex-matched cohort of community traumatic brain injury including both mild and severe cases in midlife.
View Article and Find Full Text PDFIntroduction: We investigated whether the cerebellum develops neuropathology that correlates with well-accepted Alzheimer's disease (AD) neuropathological markers and cognitive status.
Methods: We studied cerebellar cytoarchitecture in a cohort (N = 30) of brain donors. In a larger cohort (N = 605), we queried whether the weight of the contents of the posterior fossa (PF), which contains primarily cerebellum, correlated with dementia status.
Alzheimer's disease (AD) is the leading cause of dementia in older adults. Although AD progression is characterized by stereotyped accumulation of proteinopathies, the affected cellular populations remain understudied. Here we use multiomics, spatial genomics and reference atlases from the BRAIN Initiative to study middle temporal gyrus cell types in 84 donors with varying AD pathologies.
View Article and Find Full Text PDFHereditary spastic paraplegia (HSP) with thin corpus callosum can be due to a variety of genetic causes, the most common of which are biallelic variants in SPG11 (HSP11). Only six cases of neuropathologic examination of HSP11 have been reported. Here we present neuropathological findings in another case of HSP11 with novel mutation (homozygous c.
View Article and Find Full Text PDFAge-associated decline of nuclear factor erythroid 2-related factor 2 (Nrf2) activity and DNA repair efficiency leads to the accumulation of DNA damage and increased risk of cancer. Understanding the mechanisms behind increased levels of damaged DNA is crucial for developing interventions to mitigate age-related cancer risk. Associated with various health benefits, (poly)phenols and their microbially mediated phenolic catabolites represent a potential means to reduce DNA damage.
View Article and Find Full Text PDFThe appearance of misfolded and aggregated proteins is a pathological hallmark of numerous neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. Sleep disruption is proposed to contribute to these pathological processes and is a common early feature among neurodegenerative disorders. Synucleinopathies are a subclass of neurodegenerative conditions defined by the presence of α-synuclein aggregates, which may not only enhance cell death, but also contribute to disease progression by seeding the formation of additional aggregates in neighboring cells.
View Article and Find Full Text PDFObjectives: Here, we report detailed clinicopathologic evaluation of 2 individuals with pathogenic variants in , including one novel likely pathogenic splice variant. We describe the striking diversity of clinical phenotypes among family members and also the brain and spinal cord neuropathology associated with these 2 distinct variants.
Methods: Two individuals with pathogenic variants in and their families were clinically characterized, and the probands subsequently underwent extensive postmortem neuropathologic examination of their brains and spinal cords.
A number of post-mortem studies conducted in transplanted Huntington's disease (HD) patients from various trials have reported the presence of pathological and misfolded proteins, in particular mutant huntingtin (mHtt) and phosphorylated tau neuropil threads, in the healthy grafted tissue. Here, we extended these observations with histological analysis of post-mortem tissue from three additional HD patients who had received similar striatal allografts from the fetal tissue transplantation trial conducted in Los Angeles in 1998. Immunohistochemical staining was performed using anti-mHtt antibodies, EM48 and MW7, as well as anti-hyperphosphorylated tau antibodies, AT8 and CP13.
View Article and Find Full Text PDFDespite the presence of significant Alzheimer's disease (AD) pathology, characterized by amyloid β (Aβ) plaques and phosphorylated tau (pTau) tangles, some cognitively normal elderly individuals do not inevitably develop dementia. These findings give rise to the notion of cognitive 'resilience', suggesting maintained cognitive function despite the presence of AD neuropathology, highlighting the influence of factors beyond classical pathology. Cortical astroglial inflammation, a ubiquitous feature of symptomatic AD, shows a strong correlation with cognitive impairment severity, potentially contributing to the diversity of clinical presentations.
View Article and Find Full Text PDFTobacco smoke, alone or combined with alcohol, is the predominant cause of head and neck cancer (HNC). Here, we further explore how tobacco exposure contributes to cancer development by mutational signature analysis of 265 whole-genome sequenced HNC from eight countries. Six tobacco-associated mutational signatures were detected, including some not previously reported.
View Article and Find Full Text PDFInternational differences in the incidence of many cancer types indicate the existence of carcinogen exposures that have not yet been identified by conventional epidemiology make a substantial contribution to cancer burden. In clear cell renal cell carcinoma, obesity, hypertension and tobacco smoking are risk factors, but they do not explain the geographical variation in its incidence. Underlying causes can be inferred by sequencing the genomes of cancers from populations with different incidence rates and detecting differences in patterns of somatic mutations.
View Article and Find Full Text PDFAlzheimer's disease (AD), the most common aging-associated neurodegenerative dementia disorder, is defined by the presence of amyloid beta (Aβ) and tau aggregates in the brain. However, more than half of patients also exhibit aggregates of the protein TDP-43 as a secondary pathology. The presence of TDP-43 pathology in AD is associated with increased tau neuropathology and worsened clinical outcomes in AD patients.
View Article and Find Full Text PDFLarge-scale biorepositories and databases are essential to generate equitable, effective, and sustainable advances in cancer prevention, early detection, cancer therapy, cancer care, and surveillance. The Mutographs project has created a large genomic dataset and biorepository of over 7,800 cancer cases from 30 countries across five continents with extensive demographic, lifestyle, environmental, and clinical information. Whole-genome sequencing is being finalized for over 4,000 cases, with the primary goal of understanding the causes of cancer at eight anatomic sites.
View Article and Find Full Text PDFThe SORL1 gene has recently emerged as a strong Alzheimer's Disease (AD) risk gene. Over 500 different variants have been identified in the gene and the contribution of individual variants to AD development and progression is still largely unknown. Here, we describe a family consisting of 2 parents and 5 offspring.
View Article and Find Full Text PDFBackground And Objectives: The aim of this study was to compare 2 large clinicopathologic cohorts of participants aged 90+ and to determine whether the association between neuropathologic burden and dementia in these older groups differs substantially from those seen in younger-old adults.
Methods: Autopsied participants from The 90+ Study and Adult Changes in Thought (ACT) Study community-based cohort studies were evaluated for dementia-associated neuropathologic changes. Associations between neuropathologic variables and dementia were assessed using logistic or linear regression, and the weighted population attributable fraction (PAF) per type of neuropathologic change was estimated.
Dementia is a significant public health crisis; the most common underlying cause of age-related cognitive decline and dementia is Alzheimer's disease neuropathologic change (ADNC). As such, there is an urgent need to identify novel therapeutic targets for the treatment and prevention of the underlying pathologic processes that contribute to the development of AD dementia. Although age is the top risk factor for dementia in general and AD specifically, these are not inevitable consequences of advanced age.
View Article and Find Full Text PDFHuman evolution has seen the development of higher-order cognitive and social capabilities in conjunction with the unique laminar cytoarchitecture of the human cortex. Moreover, early-life cortical maldevelopment has been associated with various neurodevelopmental diseases. Despite these connections, there is currently no noninvasive technique available for imaging the detailed cortical laminar structure.
View Article and Find Full Text PDFComparing brain structure across species and regions enables key functional insights. Leveraging publicly available data from a novel mass cytometry-based method, synaptometry by time of flight (SynTOF), we applied an unsupervised machine learning approach to conduct a comparative study of presynapse molecular abundance across three species and three brain regions. We used neural networks and their attractive properties to model complex relationships among high dimensional data to develop a unified, unsupervised framework for comparing the profile of more than 4.
View Article and Find Full Text PDFThe gene has recently emerged as a strong Alzheimer's Disease (AD) risk gene. Over 500 different variants have been identified in the gene and the contribution of individual variants to AD development and progression is still largely unknown. Here, we describe a family consisting of 2 parents and 5 offspring.
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