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In this study, we report an industrial‐scale fabrication method of a multifunctional polymer composite as a scaffold material for bone tissue engineering. This study successfully demonstrated the potential of applying industrial polymer processing technologies to produce specially functionalized tissue engineering scaffolds. With the inclusion of a newly synthesized multifunctional additive, silver‐doped‐calcium phosphate (silver‐CaP), the composite material exhibited excellent osteogenic inducibility of human adipose‐derived stem cells (hASC) and satisfactory antibacterial efficacy against Escherichia coli and Staphylococcus aureus. Also, relative to previously reported methods of direct loading silver particles into polymeric materials, our composite exhibited significantly reduced silver associated cytotoxicity. The enhanced biocompatibility could be a significant advantage for materials to be used for regenerative medicine applications where clinical safety is a major consideration. The impact of different silver loading methodologies on hASC' osteogenic differentiation was also studied. Overall, the results of this study indicate a promising alternative approach to produce multifunctional scaffolds at industrial‐scale with higher throughput, lower cost, and enhanced reproducibility. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 900–910, 2019. [ABSTRACT FROM AUTHOR]

Hierarchical ultrathin NiCo 2 O 4 nanosheeets grown on uniform hollow carbon microspheres (HC@NiCo 2 O 4 ) are designed and fabricated by a solvothermal reaction followed with an annealing process. When evaluated as an anode for lithium ion batteries, the as-prepared HC@NiCo 2 O 4 microspheres exhibit excellent electrochemical performance (a high reversible capacity of 1015 mA h g −1 after 100 cycles at a current density of 0.1 A g −1 and a high capacity of 805 mA h g −1 even at a high current density of 0.5 A g −1 ). By pairing with the LiCoO 2 cathode, the HC@NiCo 2 O 4 anode also manifests excellent performance in full cells. The outstanding electrochemical performance in half and full cells can be attributed to its unique structure, which can not only promote the contact of electrode and electrolyte during the charge and discharge processes, but also shorten the transmission path of electrons and ions. More importantly, this study inspires a better design of various metal oxide/carbon electrode materials for high performance lithium ion batteries. [ABSTRACT FROM AUTHOR]

Electrospun scaffolds provide a dense framework of nanofibers with pore sizes and fiber diameters that closely resemble the architecture of native extracellular matrix. However, it generates limited three-dimensional structures of relevant physiological thicknesses. 3D printing allows digitally controlled fabrication of three-dimensional single/multimaterial constructs with precisely ordered fiber and pore architecture in a single build. However, this approach generally lacks the ability to achieve submicron resolution features to mimic native tissue. The goal of this study was to fabricate and evaluate 3D printed, electrospun, and combination of 3D printed/electrospun scaffolds to mimic the native architecture of heterogeneous tissue. We assessed their ability to support viability and proliferation of human adipose derived stem cells (hASC). Cells had increased proliferation and high viability over 21 days on all scaffolds. We further tested implantation of stacked-electrospun scaffold versus combined electrospun/3D scaffold on a cadaveric pig knee model and found that stacked-electrospun scaffold easily delaminated during implantation while the combined scaffold was easier to implant. Our approach combining these two commonly used scaffold fabrication technologies allows for the creation of a scaffold with more close resemblance to heterogeneous tissue architecture, holding great potential for tissue engineering and regenerative medicine applications of osteochondral tissue and other heterogeneous tissues. [ABSTRACT FROM AUTHOR]

In this study, we report for the first time that the primary ciliumacts as a crucial sensor for electrical field stimulation (EFS)–enhanced osteogenic response in osteoprogenitor cells. In addition, primary cilia seem to functionally modulate effects of EFS‐induced cellular calciumoscillations. Primary cilia are organelles that have recently been implicated to play a crucial sensor role for many mechanical and chemical stimuli on stem cells. Here, we investigate the role of primary cilia in EFS‐enhanced osteogenic response of human adipose‐derived stem cells (hASCs) by knocking down 2 primary cilia structural proteins, polycystin‐1 and intra flagellar protein‐88. Our results indicate that structurally integrated primary cilia are required for detection of electrical field signals in hASCs. Further more, by measuring changes of cytoplasmic calcium concentration in hASCs during EFS, our findings also suggest that primary ciliamay potentially function as a crucial calcium‐signaling nexus in hASCs during EFS.—Cai, S., Bodle, J. C., Mathieu, P. S., Amos, A., Hamouda, M., Bernacki, S., McCarty, G., Loboa, E. G. Primary cilia are sensors of electrical field stimulation to induce osteogenesis of human adipose‐derived stem cells. FASEB J. 31, 346–355 (2017) www.fasebj.org [ABSTRACT FROM AUTHOR]

Intrinsically water-stable scaffoldscomposed of ultrafine keratin fibers oriented randomly and evenlyin three dimensions were electrospun for cartilage tissue engineering.Keratin has been recognized as a biomaterial that could substantiallysupport the growth and development of multiple cell lines. Besides,three-dimensional (3D) ultrafine fibrous structures were preferredin tissue engineering due to their structural similarity to nativeextracellular matrices in soft tissues. Recently, we have developeda nontraditional approach to developing 3D fibrous scaffolds fromalcohol-soluble corn protein, zein, and verified their structuraladvantages in tissue engineering. However, keratin with highly cross-linkedmolecular structures could not be readily dissolved in common solventsfor fiber spinning, which required the remarkable drawability of solution.So far, 3D fibrous scaffolds from pure keratin for biomedical applicationshave not been reported. In this research, the highly cross-linkedkeratin from chicken feathers was de-cross-linked and disentangledinto linear and aligned molecules with preserved molecular weights,forming highly stretchable spinning dope. The solution was readilyelectrospun into scaffolds with ultrafine keratin fibers orientedrandomly in three dimensions. Due to the highly cross-linked molecularstructures, keratin scaffolds showed intrinsic water stability. Adipose-derivedmesenchymal stem cells could penetrate much deeper, proliferate, andchondrogenically differentiate remarkably better on the 3D keratinscaffolds than on 2D PLA fibrous scaffolds, 3D soy protein fibrousscaffolds, or 3D commercial nonfibrous scaffolds. In summary, theelectrospun 3D ultrafine fibrous scaffolds from keratin could be promisingcandidates for cartilage tissue engineering. [ABSTRACT FROM AUTHOR]

In this work, novel electrospun scaffolds with fibersorientedrandomly and evenly in three dimensions (3D) including in the thicknessdirection were developed based on the principle of electrostatic repulsion.This unique structure is different from most electrospun scaffoldswith fibers oriented mainly in one direction. The structure of novel3D scaffolds could more closely mimic the 3D randomly oriented fibrousarchitectures in many native extracellular matrices (ECMs). The cellculture results of this study indicated that, instead of becomingflattened cells when cultured in conventional electrospun scaffolds,the cells cultured on novel 3D scaffolds could develop into stereoscopictopographies, which highly simulated in vivo 3D cellular morphologiesand are believed to be of vital importance for cells to function anddifferentiate appropriately. Also, due to the randomly oriented fibrousstructure, improvement of nearly 5 times in cell proliferation couldbe observed when comparing our 3D scaffolds with 2D counterparts after7 days of cell culture, while most currently reported 3D scaffoldsonly showed 1.5- to 2.5-fold improvement for the similar comparison.One mechanism of this fabrication process has also been proposed andshowed that the rapid delivery of electrons on the fibers was thecrucial factor for formation of 3D architectures. [ABSTRACT FROM AUTHOR]

Abstract: A hybrid material of carbon-coated Fe2O3 submicro-particles loaded on graphene nanosheets (Fe2O3@C/GNs) is prepared by a two step route including a hydrothermal and a subsequent glucose impregnation-pyrolysis process. The obtained material is composed of GNs and ∼400 nm size Fe2O3 particles coated by thin carbon layer with a thickness of 5 nm. As an anode material for lithium ion batteries, Fe2O3@C/GNs hybrid shows an improved electrochemical performance in the initial coulombic efficiency (71%), reversible capacity (900 mA h g−1 after 50 cycles at a current of 200 mA g−1) and capacity retention rate (82% after 50 cycles). This result is much better than the synthesized bare Fe2O3 and Fe2O3/GNs electrodes. In addition to the contribution of GNs, the carbon-coated layer around Fe2O3 particles is believed to be a key factor to improve the electrochemical performance of Fe2O3. [Copyright &y& Elsevier]

In this study, we report a high-throughput fabrication method at industrial pilot scale to produce a silver-nanoparticles-doped nanoclay-polylactic acid composite with a novel synergistic antibacterial effect. The obtained nanocomposite has a significantly lower affinity for bacterial adhesion, allowing the loading amount of silver nanoparticles to be tremendously reduced while maintaining satisfactory antibacterial efficacy at the material interface. This is a great advantage for many antibacterial applications in which cost is a consideration. Furthermore, unlike previously reported methods that require additional chemical reduction processes to produce the silver-nanoparticles-doped nanoclay, an in situ preparation method was developed in which silver nanoparticles were created simultaneously during the composite fabrication process by thermal reduction. This is the first report to show that altered material surface submicron structures created with the loading of nanoclay enables the creation of a nanocomposite with significantly lower affinity for bacterial adhesion. This study provides a promising scalable approach to produce antibacterial polymeric products with minimal changes to industry standard equipment, fabrication processes, or raw material input cost.