The action of retinoic acid on spermatogonia in the testis.

For mammalian spermatogenesis to proceed normally, it is essential that the population of testicular progenitor cells, A undifferentiated spermatogonia (A), undergoes differentiation during the A to A1 transition that occurs at the onset of spermatogenesis. The commitment of the A population to differentiation and leaving a quiescent, stem-like state gives rise to all the spermatozoa produced across the lifespan of an individual, and ultimately determines male fertility. The action of all-trans retinoic acid (atRA) on the A population is the determining factor that induces this change.

Neighborhood Socioeconomic Status and Breastfeeding Initiation and Duration Among Primiparous Black Women.

Social determinants of health account for racial inequities in breastfeeding rates in the United States. There is a gap in the role of neighborhood socioeconomic status (NSES) as it relates to breastfeeding disparities. Using longitudinal data from the Black Women's Health Study, we assessed associations of NSES with breastfeeding initiation and duration in a cohort of primiparous U.

Quantitative Assessment of the Effect of Chronic Kidney Disease on Plasma P-Tau217 Concentrations.

Background And Objectives: Chronic kidney disease (CKD) is known to be associated with increased plasma phosphorylated tau217 (p-tau217) concentrations, potentially confounding the utility of plasma p-tau217 measurements as a marker of amyloid pathology in individuals with suspected Alzheimer disease (AD). In this study, we quantitatively investigate the relationship of plasma p-tau217 concentrations vs estimated glomerular filtration rate (eGFR) in individuals with CKD with and without amyloid pathology.

Methods: This was a retrospective examination of data from 2 observational cohorts from either the Mayo Clinic Study of Aging or the Alzheimer's Disease Research Center cohorts.

The effect of long-term adherence to physical activity recommendations in midlife on plasma proteins associated with frailty in the Atherosclerosis Risk in Communities (ARIC) study.

Clinical trials have shown favorable effects of exercise on frailty, supporting physical activity (PA) as a treatment and prevention strategy. Proteomics studies suggest that PA alters levels of many proteins, some of which may function as molecules in the biological processes underlying frailty. However, these studies have focused on structured exercise programs or cross-sectional PA-protein associations.

Evaluating Social Determinants of Health-Based Alternatives to Race-Based Cognitive Normative Models.

Background And Objectives: Race and ethnicity are proxy measures of sociocultural factors that influence cognitive test performance. Our objective was to compare different regression-based cognitive normative models adjusting for demographics and different combinations of easily accessible/commonly used social determinants of health (SDoH) factors, which may help describe cognitive performance variability historically captured by ethnoracial differences.

Methods: We performed cross-sectional analyses on data from Black and White participants without mild cognitive impairment/dementia in the Atherosclerosis Risk in Communities Study who attended visit 5 in 2011-2013.