Functional characterization of β-adrenergic and insulin receptor heteromers.

This study aimed to functionally characterize β-adrenergic (βAR) and insulin receptor (IR) heteromers in regard to β-arrestin 2 (βarr2) recruitment and cAMP signaling and to examine the involvement of the cytoplasmic portion of the IR β chain in heteromerization with βAR. Evidence for βAR:IR:βarr2 complex formation and the specificity of the IR:βarr2 interaction was first provided by bioinfomatics analysis. Receptor-heteromer investigation technology (HIT) then provided functional evidence of βAR:IR heterodimerization by showing isoproterenol-induced but not insulin-induced GFP-βarr2 recruitment to the βAR:IR complex; the IR:βarr2 interaction was found to only be constitutive.

Polyester type polyHIPE scaffolds with an interconnected porous structure for cartilage regeneration.

Development of artificial materials for the facilitation of cartilage regeneration remains an important challenge in orthopedic practice. Our study investigates the potential for neocartilage formation within a synthetic polyester scaffold based on the polymerization of high internal phase emulsions. The fabrication of polyHIPE polymer (PHP) was specifically tailored to produce a highly porous (85%) structure with the primary pore size in the range of 50-170 μm for cartilage tissue engineering.

Microcellular open porous monoliths for cell growth by thiol-ene polymerization of low-toxicity monomers in high internal phase emulsions.

Open porous microcellular polymers with high degrees of porosity are prepared from divinyl adipate and pentaerythritol tetrakis(3-mercaptopropionate) by thiol-ene polymerization within high internal phase emulsions. The influence of monomer ratio, droplet phase volume, and emulsion stirring rate on the morphology and mechanical properties of the products is studied. The newly produced material is successfully applied as a scaffold for osteoblastic MC3T3-E1 cells in vitro, showing increased rates of cell growth compared to material prepared by standard methods.

Hierarchically porous materials from layer-by-layer photopolymerization of high internal phase emulsions.

A combination of high internal phase emulsion (HIPE) templating and additive manufacturing technology (AMT) is applied for creating hierarchical porosity within an acrylate and acrylate/thiol-based polymer network. The photopolymerizable formulation is optimized to produce emulsions with a volume fraction of droplet phase greater than 80 vol%. Kinetic stability of the emulsions is sufficient enough to withstand in-mold curing or computer-controlled layer-by-layer stereolithography without phase separation.