@article{mccullen_zhan_onorato_bernacki_loboa_2010, title={Effect of Varied Ionic Calcium on Human Adipose-Derived Stem Cell Mineralization}, volume={16}, ISSN={["1937-3341"]}, DOI={10.1089/ten.tea.2009.0691}, abstractNote={Human adipose-derived stem cells (hASCs) are a relatively abundant and accessible stem cell source with multilineage differentiation capability and have great potential for bone tissue engineering applications. The success of bone tissue engineering is intimately linked with the production of a mineralized matrix that mimics the natural mineral present within native bone. In this study, we examined the effects of ionic calcium levels of 1.8 (normal concentration in cell culture medium), 8, and 16 mM on hASCs seeded in both two-dimensional monolayer and three-dimensional electrospun scaffolds and cultured in either complete growth medium (CGM) or osteogenic differentiation medium (ODM). The impact of calcium supplementation on hASC viability, proliferation, and mineral deposition was determined. hASCs remained viable for all experimental treatments. hASC proliferation increased with the addition of 8 mM Ca(2+) CGM, but decreased for the 16 mM Ca(2+) CGM treatment. Materials deposited by hASCs were analyzed using four techniques: (1) histological staining with Alizarin Red S, (2) calcium quantification, (3) Fourier transform infrared spectroscopy, and (4) wide-angle X-ray diffraction. Mineral deposition was significantly enhanced under both growth and osteogenic medium conditions by increasing extracellular Ca(2+). The greatest mineral deposition occurred in the ODM 8 mM Ca(2+) treatment group. Fourier transform infrared spectroscopy analysis indicated that elevated calcium concentrations of 8 mM Ca(2+) significantly increased both PO(4) amount and PO(4) to protein ratio for ODM. X-ray diffraction indicated that mineral produced with elevated Ca(2+) in both CGM and ODM had a crystalline structure characteristic of hydroxyapatite. Ionic calcium should be considered a potent regulator in hASC mineralization and could serve as a potential treatment for inducing prompt ossification of hASC-seeded scaffolds for bone tissue engineering prior to implantation.}, number={6}, journal={TISSUE ENGINEERING PART A}, author={McCullen, Seth D. and Zhan, Jackie and Onorato, Maureen L. and Bernacki, Susan H. and Loboa, Elizabeth G.}, year={2010}, month={Jun}, pages={1971–1981} }
 @article{mccullen_haslauer_loboa_2010, title={Fiber-reinforced scaffolds for tissue engineering and regenerative medicine: use of traditional textile substrates to nanofibrous arrays}, volume={20}, ISSN={["1364-5501"]}, DOI={10.1039/c0jm01443e}, abstractNote={Regenerative medicine is a promising therapeutic strategy for the repair and replacement of diseased or injured tissues and organs. The main approach for this method is the fabrication and use of scaffold materials to act as a surrogate framework and promote cell-seeded populations to develop into a mature and functional tissue. Scaffold based strategies for regenerative medicine have focused on the use of three dimensional, biocompatible, biodegradable structures to provide an adequate template for ex vivo cell expansion and maturation, native tissue ingrowth, and restoration of the original tissue qualities with respect to the tissue's biochemical constituents, morphology, form, and function. To achieve this, the use of fiber and/or textile substrates have been used as either the underlying skeleton or reinforcing agents with or without three-dimensional matrices to provide scaffolds that exhibit suitable mechanical properties, high cellularity, and better mimicry of the natural tissue organization and its resulting composition. In this article we discuss (1) fiber reinforcement in natural tissues, (2) literature examples of fiber reinforcement in engineered tissues, and (3) strategies and next steps to expand this field. Fiber reinforcement continues to be an ideal strategy for tissue scaffolds that require mechanical reinforcement while providing high surface volume in a compliant form.}, number={40}, journal={JOURNAL OF MATERIALS CHEMISTRY}, author={McCullen, Seth D. and Haslauer, Carla M. and Loboa, Elizabeth G.}, year={2010}, pages={8776–8788} }
 @article{mccullen_haslauer_loboa_2010, title={Musculoskeletal mechanobiology: Interpretation by external force and engineered substratum}, volume={43}, ISSN={["1873-2380"]}, DOI={10.1016/j.jbiomech.2009.09.017}, abstractNote={Mechanobiology aims to discover how the mechanical environment affects the biological activity of cells and how cells’ ability to sense these mechanical cues is converted into elicited cellular responses. Musculoskeletal mechanobiology is of particular interest given the high mechanical loads that musculoskeletal tissues experience on a daily basis. How do cells within these mechanically active tissues interpret external loads imposed on their extracellular environment, and, how are cell–substrate interactions converted into biochemical signals? This review outlines many of the main mechanotransduction mechanisms known to date, and describes recent literature examining effects of both external forces and cell–substrate interactions on musculoskeletal cells. Whether via application of external forces and/or cell–substrate interactions, our understanding and regulation of musculoskeletal mechanobiology can benefit by expanding upon traditional models, and shedding new light through novel investigative approaches. Current and future work in this field is focused on identifying specific forces, stresses, and strains at the cellular and tissue level through both experimental and computational approaches, and analyzing the role of specific proteins through fluorescence-based investigations and knockdown models.}, number={1}, journal={JOURNAL OF BIOMECHANICS}, author={McCullen, Seth D. and Haslauer, Carla M. and Loboa, Elizabeth G.}, year={2010}, month={Jan}, pages={119–127} }
 @inbook{mccullen_hanson_lucia_loboa_2009, title={Development and application of naturally renewable scaffold materials for bone tissue engineering}, DOI={10.1002/9781444307474.ch11}, booktitle={Nanotechnology of renewable materials}, author={McCullen, S. D. and Hanson, A. D. and Lucia, Lucian and Loboa, E. G.}, editor={L. A. Lucia and Rojas, O. J.Editors}, year={2009} }
 @misc{mcculloch_kunkel_2008, title={The fidelity of DNA synthesis by eukaryotic replicative and translesion synthesis polymerases}, volume={18}, number={1}, journal={Cell Research}, author={McCulloch, S. D. and Kunkel, T. A.}, year={2008}, pages={148–161} }
 @article{mccullen_stevens_roberts_clarke_bernacki_gorga_loboa_2007, title={Characterization of electrospun nanocomposite scaffolds and biocompatibility with adipose-derived human mesenchymal stem cells}, volume={2}, number={2}, journal={International Journal of Nanomedicine}, author={McCullen, S. D. and Stevens, D. R. and Roberts, W. A. and Clarke, L. I. and Bernacki, S. H. and Gorga, R. E. and Loboa, E. G.}, year={2007}, pages={253–263} }
 @article{mccullen_stano_stevens_roberts_monteiro-riviere_clarke_gorga_2007, title={Development, optimization, and characterization of electrospun poly(lactic acid) nanofibers containing multi-walled carbon nanotubes}, volume={105}, ISSN={["1097-4628"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000247576000079&KeyUID=WOS:000247576000079}, DOI={10.1002/app.26288}, abstractNote={Abstract}, number={3}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={McCullen, Seth D. and Stano, Kelly L. and Stevens, Derrick R. and Roberts, Wesley A. and Monteiro-Riviere, Nancy A. and Clarke, Laura I. and Gorga, Russell E.}, year={2007}, month={Aug}, pages={1668–1678} }
 @article{mccullen_stevens_roberts_ojha_clarke_gorga_2007, title={Morphological, electrical, and mechanical characterization of electrospun nanofiber mats containing multiwalled carbon nanotubes}, volume={40}, ISSN={["1520-5835"]}, DOI={10.1021/ma061735c}, abstractNote={This work focuses on the development of electrically conducting porous nanocomposite structures by the incorporation of multiwalled carbon nanotubes (MWNT) into electrospun poly(ethylene oxide) (PEO) nanofibers. Electron microscopy confirmed the presence of individual aligned MWNT encapsulated within the fibers and showed fiber morphologies with diameters of 100−200 nm. Electrical conductance measurements of the random nanofiber mats showed that by increasing the concentration of MWNT we were able to produce porous nanocomposite structures with dramatically improved electrical conductivity. Above a percolation threshold of 0.365 ± 0.09 MWNT weight percent (wt %) in PEO the conductance increased by a factor of 1012 and then became approximately constant as the concentration of MWNT was further increased. Because of this percolation threshold, for a 1 wt % loading of MWNT, the conductivity is essentially maximized. Mechanical testing confirmed that the tensile strength did not change, and there was a 3-fold...}, number={4}, journal={MACROMOLECULES}, author={McCullen, Seth D. and Stevens, Derrick R. and Roberts, Wesley A. and Ojha, Satyajeet S. and Clarke, Laura I. and Gorga, Russell E.}, year={2007}, month={Feb}, pages={997–1003} }