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Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that affects 6-7% of people worldwide (Wilcutt, 2012). MAOA is a gene that encodes monoamine oxidase A, an enzyme responsible for the regulation and metabolism of monoamines thought to be associated with ADHD. This study investigates a leucine to serine swap at amino acid position 32 in FAD-binding domain of the enzyme monoamine oxidase A. Results from in silico prediction tools and molecular dynamics modeling provide evidence to support pathogenicity of the L32S missense variant of monoamine oxidase A. 

Parkinson’s disease is the second most common neurodegenerative disease which is caused by a lack of dopamine in the brain. Parkinson 22 is a form of Parkinson’s disease caused by variations in the coiled-coil-helix-coiled-coil-helix domain containing 2 (CHCHD2) protein. This study investigates an aspartic acid-to-alanine swap on amino acid position 130 (D130A) of the CHCHD2 protein. We have employed protein modeling, conservation analysis, and molecular dynamics simulations to gain an understanding of the effects of the D130A variant on CHCHD2 protein structure and movement. 

Atherosclerosis-related cardiovascular diseases are a leading cause of mortality worldwide. Vascular smooth muscle cells (VSMCs) comprise the medial layer of the arterial wall and undergo phenotypic switching during atherosclerosis to a synthetic phenotype capable of proliferation and migration. The surrounding environment undergoes alterations in extracellular matrix (ECM) stiffness and composition in addition to an increase in addition to an increase in cholesterol content. Using an atherosclerotic murine model, we analyzed how the mechanics of VSMCs isolated from western diet fed apolipoprotein-E knockout (ApoE -/- ) and wild type (WT) mice were altered during atherosclerosis. Increased stiffness of ApoE -/- VSMCs correlated with a greater degree of stress fiber alignment as evidenced by atomic force microscopy (AFM)-generated force maps and stress fiber topography images. On type-1 collagen (COL1)-coated polyacrylamide (PA) gels of varying stiffness, WT VSMCs had higher adhesion forces to N-Cadherin (N-Cad) and COL1. ApoE -/- VSMC stiffness was significantly greater than WT cells with increased cell stiffness with increasing substrate stiffness for both ApoE -/- and WT VSMCs . In addition, ApoE -/- VSMCs showed an enhanced migration capability on COL1-coated substrates and a general decreasing trend in migration capacity with increasing substrate stiffness, correlating with the lower adhesion forces as compared to WT VSMCs. Altogether, these results demonstrate the potential contribution of the alteration in VSMC mechanics in the development of atherosclerosis. 

A nonlinear small-strain elastic theory is constructed from a systematic expansion in Biot strains, truncated at quadratic order. The primary motivation is the desire for a clean separation between stretching and bending energies for shells, which appears to arise only from reduction of a bulk energy of this type. An approximation of isotropic invariants, bypassing the solution of a quartic equation or computation of tensor square roots, allows stretches, rotations, stresses, and balance laws to be written in terms of derivatives of position. Two-field formulations are also presented. Extensions to anisotropic theories are briefly discussed.