Reduced skeletal muscle oxidative capacity and impaired training adaptations in heart failure.

Systolic heart failure (HF) is associated with exercise intolerance that has been attributed, in part, to skeletal muscle dysfunction. The purpose of this study was to compare skeletal muscle oxidative capacity and training-induced changes in oxidative capacity in participants with and without HF. Participants with HF (n = 16, 65 ± 6.

Magnetic manipulation and spatial patterning of multi-cellular stem cell aggregates.

The controlled assembly and organization of multi-cellular systems to mimic complex tissue structures is critical to the engineering of tissues for therapeutic and diagnostic applications. Recent advances in micro-scale technologies to control multi-cellular aggregate formation typically require chemical modification of the interface between cells and materials and lack multi-scale flexibility. Here we demonstrate that simple physical entrapment of magnetic microparticles within the extracellular space of stem cells spheroids during initial formation enables scaffold-free immobilization, translocation and directed assembly of multi-cellular aggregates across multiple length and time scales, even under dynamic suspension culture conditions.

Development of nano- and microscale chondroitin sulfate particles for controlled growth factor delivery.

Size scale plays an important role in the release properties and cellular presentation of drug delivery vehicles. Because negatively charged chondroitin sulfate (CS) is capable of electrostatically sequestering positively charged growth factors, CS-derived nanoscale micelles and microscale spheroids were synthesized as potential growth factor carriers to enhance differentiation of stem cells. Particles were characterized for morphology, size distribution, surface charge and cytocompatibility, as well as release of transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α).