BACKGROUND The neurobiological changes underlying the association of the apolipoprotein E (APOE) e4 allele with level of cognition are poorly understood. OBJECTIVE To test the hypothesis that amyloid load can account for (mediate) the association of the APOE e4 allele with level of cognition assessed proximate to death. METHODS There were 44 subjects with clinically diagnosed Alzheimer's di...

BACKGROUND Psychosis is common in patients with Alzheimer disease. While the relationship between psychosis and clinical variables has been examined frequently, few studies have examined the relationship between psychosis and the 2 major neuropathological hallmarks of Alzheimer disease: neurofibrillary tangles and senile plaques. We characterized the occurrence of psychosis in relation to demen...

Ultrastructural studies of neurofibrillary tangles in Alzheimer disease (AD) have demonstrated a close relationship between nuclear pores and the cytoplasmic paired helical filaments comprising the tangles, as well as nuclear irregularity in many tangle-bearing neurons; nuclear pore aggregation has been observed in nearby neurons. These observations prompted examination of the nuclear pore comp...

The distribution and density of neurofibrillary tangles and amyloid plaques was studied in a unique series of cases whose premortem cognitive status had been assessed with the Clinical Dementia Rating (CDR), including 39 nondemented cases (CDR = 0; age, 51-88 years), 15 very mildly demented cases (CDR = 0.5), and 8 severely demented (CDR = 3) cases. The initial formation of tangles and plaques ...

Neurofibrillary tangles are a feature of Alzheimer disease and other tauopathies, and although they are generally believed to be markers of neuronal pathology, there is little evidence evaluating whether tangles directly impact neuronal function. To investigate the response of cells in hippocampal circuits to complex behavioral stimuli, we used an environmental enrichment paradigm to induce exp...

To assess the role of the kynurenine pathway in the pathology of Alzheimer's disease (AD), the expression and localization of key components of the kynurenine pathway including the key regulatory enzyme tryptophan 2,3 dioxygenase (TDO), and the metabolites tryptophan, kynurenine, kynurenic acid, quinolinic acid and picolinic acid were assessed in different brain regions of triple transgenic AD ...

Clinicopathologic correlation studies are critically important for the field of Alzheimer disease (AD) research. Studies on human subjects with autopsy confirmation entail numerous potential biases that affect both their general applicability and the validity of the correlations. Many sources of data variability can weaken the apparent correlation between cognitive status and AD neuropathologic...

The capricious nature of silver impregnation techniques renders them unsuitable for bulk staining and screening sections for the presence of argyrophilic (senile) plaques and neurofibrillary tangles. For this purpose, we describe a simple, consistent and highly sensitive bulk staining method. It depends on the congophilia and resultant anomalous colour or polarization (Ladewig, 1945) that chara...