Publications by authors named "Sam E Gandy"

Background: Clinicopathological studies of Alzheimer's disease (AD) have demonstrated that synaptic or neuronal loss and clinical cognitive decline do not reliably correlate with fibrillar amyloid burden. We created a transgenic mouse model overexpressing Dutch (E693Q) mutant human amyloid precursor protein (APP) driven by the pan-neuronal Thy1 promoter. Accumulation of APP carboxyl-terminal fragments was observed in the brains of these mice, which develop an impaired learning phenotype directly proportional to brain oAβ levels.

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Introduction: World Trade Center (WTC) responders are experiencing a high risk of mild cognitive impairment (MCI) and dementia, though the etiology remains inadequately characterized. This study investigated whether WTC exposures and chronic post-traumatic stress disorder (PTSD) were correlated with plasma biomarkers characteristic of Alzheimer's disease (AD) neuropathology.

Methods: Eligible participants included WTC-exposed individuals with a baseline cognitive assessment and available plasma sample.

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Article Synopsis
  • The study investigates the connection between cognitive impairment among World Trade Center (WTC) responders and factors like genetic predisposition for Alzheimer's disease, PTSD, and educational attainment.
  • Results indicate that higher polygenic scores for Alzheimer's are linked to increased mild cognitive impairment, while higher scores for educational attainment are associated with lower risk, although PTSD symptoms and exposure severity had a stronger impact.
  • The findings suggest that many WTC responders may exhibit mild cognitive impairments similar to Alzheimer's, but the effects of PTSD and the nature of their rescue work are even more significant predictors of cognitive issues.
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Mitochondrial dysfunction, oxidative stress and reductions in thiamine-dependent enzymes have been implicated in multiple neurological disorders including Alzheimer's disease (AD). Experimental thiamine deficiency (TD) is an established model for reducing the activities of thiamine-dependent enzymes in brain. TD diminishes thiamine-dependent enzymes throughout the brain, but produces a time-dependent selective neuronal loss, glial activation, inflammation, abnormalities in oxidative metabolism and clusters of degenerating neurites in only specific thalamic regions.

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