Parkinson's Disease Inequities in Daily Cognitive Activities: An Intersectional Approach.

Objective: Intersectionality approaches to examining differences in Parkinson's disease (PD) based on racialized group, gender identity, and socioeconomic status (SES) are not well covered in the literature. Additionally, the differences in daily cognitive activities for persons diagnosed with PD by racialized group, gender, and SES are undetermined. This study was conducted to explore the differences in PD daily cognitive activities for diverse racialized groups by gender and SES. Methods: This study was a secondary analysis of the Michael J. Fox Foundation's Fox Insight online clinical dataset. Persons with PD were partitioned into 16 racialized by gender groups (Black women, Indigenous men, Latina/x women, Asian men, etc.) that were used in within-group comparisons of low-, middle-, and high-SES-a new variable comprising education and income. Results: Intersectional analyses revealed most items differed between low-SES and high-SES except for items associated with Black and Indigenous men, for whom significant differential item functioning was found between mid-SES and high-SES. Conclusions: These findings revealed that within-group differences exist and may be missed in research in which social factors are adjusted for instead of included in the model.

Tau PET burden in Brodmann areas 35 and 36 is associated with individual differences in cognition in non-demented older adults.

Introduction: The accumulation of neurofibrillary tau tangles, a neuropathological hallmark of Alzheimer's disease (AD), occurs in medial temporal lobe (MTL) regions early in the disease process, with some of the earliest deposits localized to subregions of the entorhinal cortex. Although functional specialization of entorhinal cortex subregions has been reported, few studies have considered functional associations with localized tau accumulation. Methods: In this study, stepwise linear regressions were used to examine the contributions of regional tau burden in specific MTL subregions, as measured by 18F-MK6240 PET, to individual variability in cognition. Dependent measures of interest included the Clinical Dementia Rating Sum of Boxes (CDR-SB), Mini Mental State Examination (MMSE), and composite scores of delayed episodic memory and language. Other model variables included age, sex, education, APOE4 status, and global amyloid burden, indexed by 11C-PiB. Results: Tau burden in right Brodmann area 35 (BA35), left and right Brodmann area 36 (BA36), and age each uniquely contributed to the proportion of explained variance in CDR-SB scores, while right BA36 and age were also significant predictors of MMSE scores, and right BA36 was significantly associated with delayed episodic memory performance. Tau burden in both left and right BA36, along with education, uniquely contributed to the proportion of explained variance in language composite scores. Importantly, the addition of more inclusive ROIs, encompassing less granular segmentation of the entorhinal cortex, did not significantly contribute to explained variance in cognition across any of the models. Discussion: These findings suggest that the ability to quantify tau burden in more refined MTL subregions may better account for individual differences in cognition, which may improve the identification of non-demented older adults who are on a trajectory of decline due to AD.

Comparison of male and female patients with amnestic mild cognitive impairment: Hippocampal hyperactivity and pattern separation memory performance.

INTRODUCTION: Recent studies have suggested that sex confers a differential risk in the incidence and prevalence of Alzheimer's disease (AD) thought to be the result of the increased lifespan of women compared to men. However, other factors may contribute to risk beyond the effect of increased lifespan. METHODS: This study examined the role of sex in hippocampal hyperactivity localized to the dentate gyrus (DG)/CA3 subregion of the hippocampus and associated episodic memory impairment, considered a characteristic feature of AD in patients with amnestic mild cognitive impairment (aMCI). RESULTS: While participants with aMCI showed decreased memory performance and increased activation in the DG/CA3 when compared to controls, no significant sex-related differences in performance or activation were observed. DISCUSSION: Although other factors may contribute to sex differences in the prevalence of AD these findings show that no sex differences are observed in hippocampal dysfunction characteristic of the aMCI phase of AD.

Complete Genome Sequences of Mycobacteriophages Kwksand96 and Cane17.

Bacteriophages Kwksand96 and Cane17 were isolated from Mycobacterium smegmatis mc2155. M. smegmatis is host to the highest number of phages analyzed from one species. Both mycobacteriophages were isolated from soil in west Alabama. Kwksand96 and Cane17 belong to subclusters B1 and C1, respectively, based on mycobacteriophage nucleotide sequence similarity.