Micropatterning techniques have been widely used in cell biology to study effects of controlling cell shape and size on cell fate determination at single cell resolution. Current state-of-the-art single cell micropatterning techniques involve soft lithography and micro-contact printing, which is a powerful technology, but requires trained engineering skills and certain facility support in microfabrication. These limitations require a more accessible technique.
View Article and Find Full Text PDFRationale: The cardiac conduction system (CCS) consists of distinct components including the sinoatrial node, atrioventricular node, His bundle, bundle branches, and Purkinje fibers. Despite an essential role for the CCS in heart development and function, the CCS has remained challenging to interrogate because of inherent obstacles including small cell numbers, large cell-type heterogeneity, complex anatomy, and difficulty in isolation. Single-cell RNA-sequencing allows for genome-wide analysis of gene expression at single-cell resolution.
View Article and Find Full Text PDFDuring normal lifespan, the mammalian heart undergoes limited renewal of cardiomyocytes. While the exact mechanism for this renewal remains unclear, two possibilities have been proposed: differentiated myocyte replication and progenitor/immature cell differentiation. This study aimed to characterize a population of cardiomyocyte precursors in the neonatal heart and to determine their requirement for cardiac development.
View Article and Find Full Text PDFEngineering 3D human cardiac tissues is of great importance for therapeutic and pharmaceutical applications. As cardiac tissue substitutes, extracellular matrix-derived hydrogels have been widely explored. However, they exhibit premature degradation and their stiffness is often orders of magnitude lower than that of native cardiac tissue.
View Article and Find Full Text PDFThe creation of physiologically-relevant human cardiac tissue with defined cell structure and function is essential for a wide variety of therapeutic, diagnostic, and drug screening applications. Here we report a new scalable method using Faraday waves to enable rapid aggregation of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) into predefined 3D constructs. At packing densities that approximate native myocardium (10-10 cells/ml), these hiPSC-CM-derived 3D tissues demonstrate significantly improved cell viability, metabolic activity, and intercellular connection when compared to constructs with random cell distribution.
View Article and Find Full Text PDFBackground: Validation studies of existing health literacy or numeracy tools among racial/ethnic minorities are limited.
Objective: This study assessed the validity of the Subjective Numeracy Scale (SNS), the Diabetes Numeracy Test (DNT-5), the Brief Health Literacy Screen (BHLS), and the Short Test of Functional Health Literacy in Adults (S-TOFHLA) by trait (health literacy or numeracy) and by method (subjective or objective) among non-Hispanic white (NHW), non-Hispanic black (NHB), and Hispanic patients with type 2 diabetes mellitus (T2DM).
Methods: We conducted a secondary analysis of baseline data from the Partnering to Improve Diabetes Education (PRIDE) study, a clustered randomized controlled trial testing the efficacy of a health communication intervention on T2DM outcomes at state Department of Health clinics in middle Tennessee.
This study investigated the association of chronic childhood stress exposure with acute stress-related attentional alterations that have been previously linked to vulnerability to mental and physical illness in early adulthood. Participants were randomized in a crossover design to complete both a mild laboratory social stress task and a computerized task assessing attentional bias to socially threatening words. Salivary cortisol was measured throughout the study.
View Article and Find Full Text PDFInitiation of force generation during vascular smooth muscle contraction involves a rise in intracellular calcium ([Ca(2+)]i) and phosphorylation of myosin light chains (MLC). However, reversal of these two processes alone does not account for the force inhibition that occurs during relaxation or inhibition of contraction, implicating that other mechanisms, such as actin cytoskeletal rearrangement, play a role in the suppression of force. In this study, we hypothesize that forskolin-induced force suppression is dependent upon changes in actin cytoskeletal dynamics.
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