ORCID Profile
0000-0002-9245-7774
Current Organisation
Tufts University
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Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Wiley
Date: 27-10-2017
Abstract: Structure-property relationships of silk is an intriguing topic for silk-based biomaterials research since these features are related to biomimicking the processing in natural silk fiber formation which results in excellent mechanical properties. Strain-stiffening is common for spider silks and nonmulberry silkworm silks. However, the structural origin of strain-stiffening remains unclear. In this paper, the strain-dependent structural change of Antheraea pernyi silkworm silk is studied by X-ray fiber diffraction and Fourier transform infrared spectroscopy under stretching. Based on a combination of mechanical and structural analysis, the molecular origins of strain-stiffening in A. pernyi silk were determined. The relatively high content of the β-sheets within the amorphous domains in A. pernyi silk is responsible for strain-stiffening, where "molecular spindles" enhance the extensibility and toughness of the fiber.
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: CRC Press
Date: 28-07-2017
Publisher: Elsevier BV
Date: 03-2015
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Wiley
Date: 19-11-2011
DOI: 10.1002/POLB.23003
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 17-01-2017
Abstract: (Re)Building a Kidney is a National Institute of Diabetes and Digestive and Kidney Diseases-led consortium to optimize approaches for the isolation, expansion, and differentiation of appropriate kidney cell types and the integration of these cells into complex structures that replicate human kidney function. The ultimate goals of the consortium are two-fold: to develop and implement strategies for in vitro engineering of replacement kidney tissue, and to devise strategies to stimulate regeneration of nephrons in situ to restore failing kidney function. Projects within the consortium will answer fundamental questions regarding human gene expression in the developing kidney, essential signaling crosstalk between distinct cell types of the developing kidney, how to derive the many cell types of the kidney through directed differentiation of human pluripotent stem cells, which bioengineering or scaffolding strategies have the most potential for kidney tissue formation, and basic parameters of the regenerative response to injury. As these projects progress, the consortium will incorporate systematic investigations in physiologic function of in vitro and in vivo differentiated kidney tissue, strategies for engraftment in experimental animals, and development of therapeutic approaches to activate innate reparative responses.
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 08-03-2013
Publisher: American Chemical Society (ACS)
Date: 18-12-2020
Publisher: Elsevier BV
Date: 10-2011
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7SM00446J
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 28-03-2008
DOI: 10.1021/BM701235F
Abstract: Silk-based biomaterial systems have been previously explored for a variety of medical and nonmedical materials needs. The unique biophysical features of silks provide options to generate highly tailored structures and morphologies with this unique family of fibrous proteins. To exploit these features, we have optimized the all aqueous processing of silk fibroin into novel surface nanopatterned protein materials. We have exploited control of this nanomorphology to optimize the optical features of these silk protein systems. We demonstrate control of surface morphology down to 125 nm, with fidelity over large length scales. This surface nanopatterning allows the silk protein to be formed into diffractive optics such as diffraction gratings, pattern generators, and lenses due to novel aqueous processing into optically clear materials via control of beta sheet crystallinity. Further, we incorporate biological components, such as hemoglobin and the enzyme peroxidase, during the process of forming the silk diffraction gratings. The ambient processing of the silk protein in water, in combination with these bioactive components, allows these entrained molecules to retain activity and provide added functions and selectivity to the optically active silk films. Thus, combinations of biochemical and optical readout is feasible and provides in a single, disposable/all degradable element with both spectral discrimination and biological function. These new surface nanopatterned, bioactive silk protein-based material systems offer a unique combination of features potentially useful for a range of biosensor needs, particularly when considered in concert with the remarkable mechanical properties of these proteins, their biocompatibility, and controllable biodegradation.
Publisher: Public Library of Science (PLoS)
Date: 02-02-2011
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5TB00353A
Abstract: The developed biphasic scaffold featured a gradient of structural, mechanical and biological cues to match the segments of osteochondral tissue.
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
DOI: 10.1021/JACS.0C06516
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Elsevier BV
Date: 05-2012
Publisher: Royal Society of Chemistry (RSC)
Date: 2009
DOI: 10.1039/B905802H
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Association for the Advancement of Science (AAAS)
Date: 14-10-2022
Abstract: Spider silks are among the toughest known materials and thus provide models for renewable, biodegradable, and sustainable biopolymers. However, the entirety of their ersity still remains elusive, and silks that exceed the performance limits of industrial fibers are constantly being found. We obtained transcriptome assemblies from 1098 species of spiders to comprehensively catalog silk gene sequences and measured the mechanical, thermal, structural, and hydration properties of the dragline silks of 446 species. The combination of these silk protein genotype-phenotype data revealed essential contributions of multicomponent structures with major ullate spidroin 1 to 3 paralogs in high-performance dragline silks and numerous amino acid motifs contributing to each of the measured properties. We hope that our global s ling, comprehensive testing, integrated analysis, and open data will provide a solid starting point for future biomaterial designs.
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 11-08-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Elsevier BV
Date: 11-2010
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Elsevier BV
Date: 2019
DOI: 10.1016/J.MSEC.2018.10.053
Abstract: Injectable silk hydrogels are ideal carriers of therapeutic agents due to their biocompatibility and low immunogenicity. Injectable silk hydrogels for bone regeneration have been previously developed but often utilize expensive biologics. In this study, we have developed an injectable silk composite incorporated with a triphasic ceramic called MSM-10 (54 Mg
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 26-05-2016
DOI: 10.1002/JBM.A.35772
Abstract: A range of non-animal collagens has been described, derived from bacterial species, which form stable triple-helical structures without the need for secondary modification to include hydroxyproline in the sequence. The non-animal collagens studied to date are typically smaller than animal interstitial collagens, around one quarter the length and do not pack into large fibrillar aggregates like those that are formed by the major animal interstitial collagens. A consequence of this for biomedical products is that fabricated items, such as collagen sponges, are not as mechanically and dimensionally stable as those of animal collagens. In the present study, we examined the production of larger, polymeric forms of non-animal collagens through introduction of tyrosine and cysteine residues that can form selective crosslinks through oxidation. These modifications allow the formation of larger aggregates of the non-animal collagens. When Tyr residues were incorporated, gels were obtained. And with Cys soluble aggregates were formed. These materials can be formed into sponges that are more stable than those formed without these modifications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2369-2376, 2016.
Publisher: American Chemical Society (ACS)
Date: 31-03-2020
Abstract: Sustained, local delivery of the antibiotic ciprofloxacin under different formats from porous silk protein-based memory foam systems was studied. Similarly, protease XIV was incorporated during processing to provide control of the degradation kinetics of the silk materials. In vitro antibiotic release studies combined with degradation assessments were utilized to assess the mechanisms and kinetics of release from the silk materials. The sequestered protease XIV affected the degradation profiles of the silk foams yet did not impact the release kinetics of the ciprofloxacin, which was controlled by solubility and diffusion of the drug. The ability to tune the release of ciprofloxacin between 1 and 200 days, combined with the option to modulate the degradation rate up to 80% in 2 weeks via incorporation of a protease, suggests utility for drug release devices. Further, we anticipate that this approach could also be extended to other medical implant needs and other drugs.
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Wiley
Date: 14-01-2022
Abstract: Regenerated silk fibers typically fall short of silkworm cocoon fibers in mechanical properties due to reduced fiber crystal structure and alignment. One approach to address this has been to employ inorganic materials as reinforcing agents. The present study avoids the need for synthetic additives, demonstrating the first use of exfoliated silk nanofibers to control silk solution crystallization, resulting in all‐silk pseudocomposite fibers with remarkable mechanical properties. Incorporating only 0.06 wt% silk nanofibers led to a ≈44% increase in tensile strength (over 600 MPa) and ≈33% increase in toughness (over 200 kJ kg −1 ) compared with fibers without silk nanofibers. These remarkable properties can be attributed to nanofiber crystal seeding in conjunction with fiber draw. The crystallinity nearly doubled from ≈17% for fiber spun from pure silk solution to ≈30% for the silk nanofiber reinforced s le. The latter fiber also shows a high degree of crystal orientation with a Herman's orientation factor of 0.93, a value which approaches that of natural degummed B. mori silk cocoon fiber (0.96). This study provides a strong foundation to guide the development of simple, eco‐friendly methods to spin regenerated silk with excellent properties and a hierarchical structure that mimics natural silk.
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Hindawi Limited
Date: 06-04-2017
DOI: 10.1002/TERM.2152
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C4TB01073F
Abstract: Scaffold-based tissue engineering strategies are being explored for the management and reconstruction of damaged or diseased skeletal tissues, the effective treatment of which has remained a significant global healthcare challenge.
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 23-11-2018
Abstract: In-stent restenosis caused by tumor ingrowth is a major problem for patients undergoing stent placement because conventional stents often lack sustainable antitumor capabilities. The aim of this work is to develop a silk fibroin (SF)-based nanofibrous membrane that is loaded with combined-therapy drugs by using electrospinning technologies, which is further coated on a polydioxanone (PDO) stent and used for the treatment of colorectal cancer (CRC). In order to improve treatment effectiveness, a combination of therapeutic drugs, i.e., curcumin (CUR) and 5-fluorouracil (5-FU), is dissolved into SF solution and then eletrospun onto the surface of the PDO stent. The morphology, secondary structure, and in vitro drug release profiles of the membranes are characterized. The antitumor efficacy is assessed in vitro and in vivo using a human CRC cell line and normal cells, and tumor-bearing nude mice. In vitro and in vivo studies on the nanofibrous memembrane-coating demonstrate improved antitumor effects for the CUR/5-FU dual drug system which can be attributed to cell cycle arrest in the S phase in association with induced apoptosis in tumor cells by blocking signal transducer and activator of transcription3 (Stat3) and nuclear factor kappa beta (NF-kB) signaling pathways, suggesting potential in the treatment of CRC in the future.
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Elsevier BV
Date: 05-2017
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Elsevier BV
Date: 04-2014
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 29-07-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 09-06-2010
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: The Optical Society
Date: 27-01-2014
DOI: 10.1364/BOE.5.000596
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Elsevier BV
Date: 12-2011
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 21-07-2020
Publisher: Elsevier BV
Date: 07-2019
Publisher: American Chemical Society (ACS)
Date: 07-06-2013
DOI: 10.1021/BM400303W
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: IEEE
Date: 06-2013
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Proceedings of the National Academy of Sciences
Date: 27-12-2016
Abstract: Engineering multiple functions in a single material format is a key design parameter to fabricate devices that can perform at the confluence between biology and technology. This can be achieved by designing materials with hierarchical structures across several scales or by embedding active molecules at the point of material formation. These approaches have been successfully pursued to engineer 2D materials formats. However, current technologies have limited the formation of 3D constructs with orthogonal functions. In this study, we demonstrate an entirely water-based sol–gel–solid process to generate 3D mechanical forms that embed biological (and other) functions. This approach is a step toward the development of multifunctional devices that may liaise between the biotic and abiotic worlds.
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
DOI: 10.1021/JACS.0C04253
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 14-02-2013
DOI: 10.1021/JA312647N
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 10-2013
Abstract: New multifunctional, degradable, polymeric biomaterial systems would provide versatile platforms to address cell and tissue needs in both in vitro and in vivo environments. While protein‐based composites or alloys are the building blocks of biological organisms, similar systems have not been largely exploited, to date, to generate ad hoc biomaterials able to control and direct biological functions by recapitulating their inherent structural and mechanical complexities. Therefore, we have recently proposed silktropoelastin material platforms that are able to conjugate a mechanically robust and durable protein, silk, to a highly flexible and biologically active protein, tropoelastin. This review focuses on the elucidation of the interactions between silk and tropoelastin to control the structure of the material its properties, and ultimately functions. In addition, an approach is provided for novel material designs to provide tools to control biological outcomes through surface roughness, elasticity, and net charge for neuronal and mesenchymal stem‐cell‐based tissue engineering.
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 10-2020
Publisher: AIP Publishing
Date: 04-09-2017
DOI: 10.1063/1.4998950
Abstract: Silk fibroin possesses unique properties for bio-functional optical interfaces and has been attracting increasing interest as an optical material. Here, we report on the refractive index and absorption coefficient of silk fibroin extracted from Bombyx mori, Antheraea mylitta, Samia ricini, and Antheraea assamensis. The influence of protein molecular weight, residual water content, and crystallinity on refractive index was investigated. The parameters for the Cauchy dispersion law and Urbach absorption were determined for each of the silk fibroins. By exploiting the differences in refractive index between the different fibroins, an all-protein slab waveguide was fabricated.
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Elsevier BV
Date: 07-2012
Publisher: American Chemical Society (ACS)
Date: 16-05-2022
DOI: 10.1021/ACSBIOMATERIALS.2C00099
Abstract: Device-associated infections remain a clinical challenge. The common strategies to prevent bacterial infection are either toxic to healthy mammalian cells and tissue or involve high doses of antibiotics that can prompt long-term negative consequences. An antibiotic-free coating strategy to suppress bacterial growth is presented herein, which concurrently promotes bone cell growth and moderates the dissolution kinetics of resorbable magnesium (Mg) biomaterials. Pure Mg as a model biodegradable material was coated with gallium-doped strontium-phosphate through a chemical conversion process. Gallium was distributed in a gradual manner throughout the strontium-phosphate coating, with a compact structure and a gallium-rich surface. It was demonstrated that the coating protected the underlying Mg parts from significant degradation in minimal essential media at physiological conditions over 9 days. In terms of bacteria culture, the liberated gallium ions from the coatings upon Mg specimens, even though in minute quantities, inhibited the growth of Gram-positive
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Elsevier BV
Date: 06-2014
DOI: 10.1016/J.BIOMATERIALS.2014.03.024
Abstract: Blended polymers are used extensively in many critical medical conditions as components of permanently implanted devices. Hybrid protein polymers containing recombinant human tropoelastin and silk fibroin have favorable characteristics as implantable scaffolds in terms of mechanical and biological properties. A firefly luciferase transgenic mouse model was used to monitor real-time IL-1β production localized to the site of biomaterial implantation, to observe the acute immune response (up to 5 days) to these materials. Significantly reduced levels of IL-1β were observed in silk/tropoelastin implants compared to control silk only implants at 1, 2 and 3 days post-surgery. Subsequently, mice (n = 9) were euthanized at 10 days (10D) and 3 weeks (3W) post-surgery to assess inflammatory cell infiltration and collagen deposition, using histopathology and immunohistochemistry. Compared to control silk only implants, fewer total inflammatory cells were found in silk/tropoelastin (∼29% at 10D and ∼47% at 3W). Also fewer ingrowth cells (∼42% at 10D and ∼63% at 3W) were observed within the silk/tropoelastin implants compared to silk only. Lower IL-6 (∼52%) and MMP-2 (∼84%) (pro-inflammatory) were also detected for silk/tropoelastin at 10 days. After 3 weeks implantation, reduced neovascularization (vWF ∼43%), fewer proliferating cells (Ki67 ∼58% and PCNA ∼41%), macrophages (F4/80 ∼64%), lower IL-10 (∼47%) and MMP-9 (∼55%) were also observed in silk/tropoelastin materials compared to silk only. Together, these results suggest that incorporation of tropoelastin improves on the established biocompatibility of silk fibroin, uniquely measured here as a reduced foreign body inflammatory response.
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 08-2023
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Wiley
Date: 11-08-2016
DOI: 10.1002/JBM.A.35850
Publisher: Elsevier BV
Date: 10-2021
Publisher: Wiley
Date: 09-08-2016
DOI: 10.1002/JBM.A.35851
Abstract: The physical, chemical, and bioactive cues provided by biomaterials are critical for spinal cord regeneration following injury. In this study, we investigated the bioactivity of a silk-based scaffold for nerve tissue remodeling that featured morphological guidance in the form of ridges as well as bioactive molecules. Multichannel/laminin (LN) silk scaffolds stimulated growth, development, and the extension of primary hippoc al neurons after 7 days of culture in vitro. And then, the multichannel/LN silk scaffolds were implanted into 2-mm-long hemisection defects in Sprague-Dawley rat spinal cords for 70 days to evaluate their bioactivities of spinal cord remolding. Our results demonstrated that animal behavior was significantly improved in the multichannel/LN group, as evaluated by Basso-Beattie-Bresnahan score, whereas the implantation of multichannels and random pores groups resulted in recurring limps. Moreover, histology and immunohistochemical staining revealed an increase in blood vessels and expression of growth associated protein-43 and neurofilament-200 as well as reduced expression of glial fibrillary acidic protein in the multichannel/LN group, which contributed to the rebuilding of spinal cord defects. Thus, multichannel/LN silk scaffolds mediated cell migration, stimulated blood capillary formation, and promoted axonal extension, suggesting the utility of these scaffolds for spinal cord reconstruction. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 3045-3057, 2016.
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: Springer Science and Business Media LLC
Date: 2011
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Wiley
Date: 25-07-2011
DOI: 10.1002/JBM.A.33158
Publisher: Elsevier BV
Date: 03-2010
DOI: 10.1016/J.TIBTECH.2009.12.001
Abstract: Advances in tissue engineering have traditionally led to the design of scaffold- or matrix-based culture systems that better reflect the biological, physical and biochemical environment of the natural extracellular matrix. Although their clinical applications in regenerative medicine tend to receive most of the attention, it is obvious that other areas of biomedical research could be well served by the powerful tools that have already been developed in tissue engineering. In this article, we review the recent literature to demonstrate how tissue engineering platforms can enhance in vitro and in vivo models of tumorigenesis and thus hold great promise to contribute to future cancer research.
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 23-04-2020
Publisher: American Chemical Society (ACS)
Date: 19-06-2020
Publisher: Proceedings of the National Academy of Sciences
Date: 13-11-2001
Abstract: Collagen is a key fibrous protein in biological systems, characterized by a complex structural hierarchy as well as the ability to self-assemble into liquid crystalline mesophases. The structural features of collagen influence cellular responses and material properties, with importance for a wide range of biomaterials and tissue architectures. The mechanism by which fibrillar collagen structures form from liquid crystalline mesophases is not well characterized. We report positive printing of collagen and a collagen-like peptide down to 30–50-nm line widths, using the atomic force microscopy technique of dip-pen nanolithography. The method preserved the triple-helical structure and biological activity of collagen and even fostered the formation of characteristic higher levels of structural organization. The “direct-write” capability of biologically relevant molecules, while preserving their structure and functionality, provides tremendous flexibility in future biological device applications and in proteomics arrays, as well as a new strategy to study the important hierarchical assembly processes of biological systems.
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: American Chemical Society (ACS)
Date: 22-04-2020
Publisher: Hindawi Limited
Date: 24-07-2015
DOI: 10.1002/TERM.2070
Abstract: Bioactive ceramic scaffolds represent competitive choices for clinical bone reconstruction, but their widespread use is restricted by inherent brittleness and weak mechanical performance under load. This study reports the development of strong and tough bioactive scaffolds suitable for use in load-bearing bone reconstruction. A strong and bioactive ceramic scaffold (strontium-hardystonite-gahnite) is combined with single and multiple coating layers of silk fibroin to enhance its toughness, producing composite scaffolds which match the mechanical properties of cancellous bone and show enhanced capacity to promote in vitro osteogenesis. Also reported for the first time is a comparison of the coating effects obtained when a polymeric material is coated on ceramic scaffolds with differing microstructures, namely the strontium-hardystonite-gahnite scaffold with high-density struts as opposed to a conventional ceramic scaffold, such as biphasic calcium phosphate, with low-density struts. The results show that silk coating on a unique ceramic scaffold can lead to simple and effective enhancement of its mechanical and biological properties to suit a wider range of applications in clinical bone reconstruction, and also establish the influence of ceramic microstructure on the effectiveness of silk coating as a method of reinforcement when applied to different types of ceramic bone graft substitutes. Copyright © 2015 John Wiley & Sons, Ltd.
Publisher: Walter de Gruyter GmbH
Date: 04-2013
Abstract: The inability of adult cells to produce well-organized, robust elastic fibers has long been a barrier to the successful engineering of certain tissues. In this review, we focus primarily on elastin with respect to tissue-engineered vascular substitutes. To understand elastin regulation during normal development, we describe the role of various elastic fiber accessory proteins. Biochemical pathways regulating expression of the elastin gene are addressed, with particular focus on tissue-engineering research using adult-derived cells.
Publisher: AIP Publishing
Date: 20-09-2010
DOI: 10.1063/1.3486157
Abstract: In this paper, we report on gold nanoparticle (GNP) doped silk films as an implantable and degradable heating element activated by light, which can be potentially used for wireless powering of implanted microdevices. Proof-of-concept experiments have been conducted by casting a GNP doped silk film on a miniature thermal-power chip, which generates ∼20 mW when illuminated by a green laser with an output power of 450 mW/mm2 at 532 nm.
Publisher: Future Medicine Ltd
Date: 03-2015
DOI: 10.2217/NNM.14.230
Abstract: Aim: Silk-tropoelastin alloys, composed of recombinant human tropoelastin and regenerated Bombyx mori silk fibroin, are an emerging, versatile class of biomaterials endowed with tunable combinations of physical and biological properties. Electrodeposition of these alloys provides a programmable means to assemble functional gels with both spatial and temporal controllability. Materials & methods: Tropoelastin-modified silk was prepared by enzymatic coupling between tyrosine residues. Hydrogel coatings were electrodeposited using two wire electrodes. Results & discussion: Mechanical characterization and in vitro cell culture revealed enhanced adhesive capability and cellular response of these alloy gels as compared with electrogelled silk alone. Conclusion: These electro-depositable silk-tropoelastin alloys constitute a suitable coating material for nanoparticle-based drug carriers and offer a novel opportunity for on-demand encapsulation/release of nanomedicine.
No related grants have been discovered for David Kaplan.