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Background: While traditional histologic neuropathological assessment of neurodegenerative disease has tremendous diagnostic value, insights into neurodegeneration's pathophysiological underpinnings can be significantly enhanced with large‐scale quantitative analyses. As part of the Seattle Alzheimer's Disease Brain Cell Atlas (SEA‐AD), we present a neuropathology dataset across 84 brains spanning the spectrum of AD neuropathologic change donated by UW Alzheimer's Disease Research Center and Adult Changes in Thought study participants. Method: Human brain tissue was collected at rapid autopsy (postmortem interval <12 hours). One hemisphere (randomly selected) was embedded in alginate for uniform coronal slicing (4mm), with alternating slabs fixed in 10% neutral buffered formalin or frozen in a dry ice isopentane slurry. Superior and Middle Temporal Gyrus (MTG) was sampled from fixed slabs and subjected to standard processing, embedding, sectioning (5µm), histochemical (H&E/Luxol fast blue), and immunohistochemical (duplex pTau and pTDP‐43, Aβ and Iba1, and monoplex GFAP, a‐synuclein, and NeuN) labeling. HALO image analysis software (Indica Labs, Albuquerque NM) was used to define and quantify relevant cellular and pathological features within each cortical layer (Figures 1‐3). Result: 84 individuals were included in these analyses (Table 1). While quantitative metrics of pTau and Aβ aligned with traditional neuropathological measures, they showed substantial variability within discrete diagnostic stages (Figure 4). These findings were robust to quantification (discrete count vs. total area stained) and normalization (total nuclei vs. total area analyzed) methods, and highlight the importance of deploying highly quantitative, continuous measures of pathology in the study of neurodegeneration. This unique resource provides spatially preserved measures of pathologic burden across the spectrum of AD with potential for correlative analysis across pathologies, clinical and biomarker parameters, and omics applications to better support the identification of vulnerable cell types in early stages of AD progression, the principal goal of SEA‐AD. Conclusion: Here we present a large‐scale quantitative neuropathology dataset, which enables analysis of pathological proteins and cell types at unprecedented scale and accuracy. Little is known about the interactions of AD‐relevant cell types with pathologic peptides across disease progression. The presented analyses exemplify the potential of this unique publicly‐accessible resource to identify and quantify novel disease‐relevant relationships. [ABSTRACT FROM AUTHOR]

Background: The trace of memory has not been well studied in middle temporal gyrus (MTG). Although neuronal loss is minimal in most cortical regions of the aging brain, changes in synaptic physiology of ageing neurons may contribute to altered connectivity. In the Adult Changes in Thought (ACT) autopsy cohort, we explored if memory decline is associated with NeuN (neuronal nuclear protein), a biomarker for mature neurons, in MTG. Method: ACT study participants were 5,763 older adults randomly sampled from an integrated healthcare delivery system in King County, Washington. We standardized composite memory scores to N(0,1) at baseline. We calculated slopes of memory decline over time using mixed‐effects models, where time was parameterized as years before death. Among 69 individuals who underwent brain autopsy, we measured NeuN positive cell count from whole slide image analysis using HALO in five tissue layers (molecular, external granular, external pyramidal, internal granular, internal pyramidal + multiform) from brain tissue in MTG. In each layer, we normalized NeuN positive cell count over the tissue area. We derived an average NeuN positive cell count (ANPCC) by averaging the values across the layers (Figure 1). We regressed ANPCC on memory slope, adjusting for age at death and sex. In secondary models, we added disease severity (Braak staging) and presence of APOE ε4 alleles separately. We also analyzed layer‐specific ANPCC. Result: 64 individuals were included for analysis (Table 1). Memory decline in this sample was 0.10 units per year, similar to the entire cohort. Slower decline in memory (β = 0.10; p‐value = 0.002) was significantly associated with increased average ANPCC (Table 2). Adjusting for Braak staging and APOE ε4 gave similar results. Findings were statistically significant across all but the molecular layer. Conclusion: ANPCC is associated with slower memory decline in multiple neocortical layers in MTG, irrespective of disease staging or APOE genotype. Since Alzheimer's disease afflicts adult neuronal populations, survival mechanisms in mature neurons are likely to be either reversed or circumvented during neurodegeneration. Further analyses are needed to understand the functional range of NeuN and processes that lead to loss of NeuN immunoreactivity in cells. [ABSTRACT FROM AUTHOR]

The study examined the effect of Avian Influenza (AI) on the household consumption of poultry products during the first outbreak of the disease in Ogun State, Nigeria. Furthermore, determinants influencing poultry products consumption during the outbreak were identified. A multi-stage sampling procedure was used to select 120 households and a well structured questionnaire was used for data collection. The data collected were analyzed using descriptive statistics, independent t-test and regression techniques. Egg consumption reduced significantly dropping from an average of 40 eggs/month to 29 eggs/month (p=0.038) during the AI outbreak. The average chicken expenditure/month dropped significantly from N1116.44 to N991.96 (p=0.019). Awareness of AI, educational level and amount spent on food consumption were the significant factors that contributed to the consumption of poultry products during the AI outbreak. The study therefore recommended that members of the public should be properly sensitized on safety precautions that should be cultivated before the consumption of poultry products especially during outbreaks of diseases. [ABSTRACT FROM AUTHOR]