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Saadatkish N, Nouri Khorasani S, Morshed M, Allafchian AR, Beigi MH, Masoudi Rad M, Esmaeely Neisiany R, Nasr-Esfahani MH. A ternary nanofibrous scaffold potential for central nerve system tissue engineering. J Biomed Mater Res A 2018; 106:2394-2401. [PMID: 29637736 DOI: 10.1002/jbm.a.36431] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 03/19/2018] [Accepted: 03/29/2018] [Indexed: 01/13/2023]
Abstract
In the present research, a ternary polycaprolactone (PCL)/gelatin/fibrinogen nanofibrous scaffold for tissue engineering application was developed. Through this combination, PCL improved the scaffold mechanical properties; meanwhile, gelatin and fibrinogen provided more hydrophilicity and cell proliferation. Three types of nanofibrous scaffolds containing different fibrinogen contents were prepared and characterized. Morphological study of the nanofibers showed that the prepared nanofibers were smooth, uniform without any formation of beads with a significant reduction in nanofiber diameter after incorporation of fibrinogen. The chemical characterization of the scaffolds confirmed that no chemical reaction occurred between the scaffold components. The tensile test results of the scaffolds showed that increasing in fibrinogen content led to a decrease in mechanical properties. Furthermore, adipose-derived stem cells were employed to evaluate cell-scaffold interaction. Cell culture results indicated that higher cell proliferation occurred for the higher amount of fibrinogen. Statistical analysis was also carried out to evaluate the significant difference for the obtained results of water droplet contact angle and cell culture. Therefore, the results confirmed that PCL/gel/fibrinogen scaffold has a good potential for tissue engineering applications including central nerve system tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A:2394-2401, 2018.
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Affiliation(s)
- Niloufar Saadatkish
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Saied Nouri Khorasani
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Mohammad Morshed
- Department of Textile Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Ali-Reza Allafchian
- Nanotechnology and Advanced Materials, Institute Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Mohammad-Hossein Beigi
- Department of Cellular Biotechnology at Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Maryam Masoudi Rad
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Rasoul Esmaeely Neisiany
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Mohammad-Hossein Nasr-Esfahani
- Department of Cellular Biotechnology at Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
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102
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Song SJ, Shin YC, Kim SE, Kwon IK, Lee JH, Hyon SH, Han DW, Kim B. Aligned laminin core-polydioxanone/collagen shell fiber matrices effective for neuritogenesis. Sci Rep 2018; 8:5570. [PMID: 29615798 PMCID: PMC5882927 DOI: 10.1038/s41598-018-23958-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/23/2018] [Indexed: 11/21/2022] Open
Abstract
Neural tissue regeneration is a significant challenge, because severe nerve injury is quite difficult to regenerate spontaneously. Although, many studies have been devoted to promote nerve regeneration, there are still many technical challenges to achieve satisfactory results. In this study, we designed biomimetic matrices composed of aligned laminin core-polydioxanone/collagen shell (Lam-PDO/Col) fibers, which can provide both topographical and biochemical cues for promoting neuritogenesis. The aligned Lam-PDO/Col core-shell fiber matrices were fabricated by magnetic field-assisted electrospinning with the coaxial system, and their potential as biofunctional scaffolds for promoting neuritogenesis was explored. It was demonstrated that the aligned Lam-PDO/Col core-shell fibers were successfully fabricated, and the laminin in the core of fibers was steadily and continuously released from fibers. In addition, the cellular behaviors of hippocampal neuronal cells on the matrices were significantly enhanced. Moreover, the aligned Lam-PDO/Col fiber matrices effectively improved and guided neurite outgrowth as well as the neurogenic differentiation by providing both topographical and biochemical cues through aligned fiber structure and sustained release of laminin. Collectively, it is suggested that the aligned Lam-PDO/Col core-shell fiber matrices are one of the most promising approaches for promoting neuritogenesis and neural tissue regeneration.
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Affiliation(s)
- Su-Jin Song
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241, Republic of Korea
| | - Yong Cheol Shin
- Research Center for Energy Convergence Technology, Pusan National University, Busan, 46241, Republic of Korea
| | - Sung Eun Kim
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241, Republic of Korea
| | - Il Keun Kwon
- Department of Dental Materials, School of Dentistry, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Jong-Ho Lee
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, 03080, Republic of Korea
| | - Suong-Hyu Hyon
- Center for Fiber and Textile Science, Kyoto Institute of Technology, Matsugasaki, Kyoto, 606-8585, Japan
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241, Republic of Korea.
| | - Bongju Kim
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul, 03080, Republic of Korea.
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103
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Zhang C, Driver N, Tian Q, Jiang W, Liu H. Electrochemical deposition of conductive polymers onto magnesium microwires for neural electrode applications. J Biomed Mater Res A 2018. [PMID: 29520971 DOI: 10.1002/jbm.a.36385] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Metals are widely used in electrode design for recording neural activities because of their excellent electrical conductivity and mechanical strength. However, there are still serious problems related to these currently used metallic electrodes, including tissue damage due to the mechanical mismatch between metals and neural tissues, fibrosis, and electrode fouling and encapsulation that lead to the loss of signal and eventual failure. In this study, a biocompatible, biodegradable, and conductive electrode was created. Specifically, pure magnesium (Mg) microwire with a diameter of 127 µm was used as the electrode substrate and the conductive polymer, that is, poly(3,4-ethylenedioxythiophene) (PEDOT), was electrochemically deposited onto Mg microwires to decrease corrosion rate and improve biocompatibility of the electrodes for potential neural electrode applications. Both chronopotentiometry and cyclic voltammetry (CV) methods and the associated parameters for electrochemical deposition of PEDOT onto Mg microwires were investigated, such as deposition current, deposition temperature, voltage, sweep rate, cycle number, and duration. The CV method from -2.0 to 1.25 V for 1 cycle at a cycle duration of 600 s with a sweep rate of 5 mV/s at 65°C led to a consistent, uniform, and complete PEDOT coating on Mg microwires. The surface conditions of Mg microwires also affected the quality of PEDOT coating. The corrosion rate of PEDOT-coated Mg microwire was 0.75 mm/year, much slower than the noncoated Mg microwire that showed a corrosion rate of 1.78 mm/year. The optimal Mg microwires with PEDOT coating could potentially serve as biodegradable electrodes for neural recording and stimulation applications. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1887-1895, 2018.
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Affiliation(s)
- Chaoxing Zhang
- Materials Science and Engineering Program, University of California at Riverside, 900 University Avenue, Riverside, California, 92521
| | - Nathan Driver
- Department of Bioengineering, University of California at Riverside, 900 University Avenue, Riverside, California, 92521
| | - Qiaomu Tian
- Department of Bioengineering, University of California at Riverside, 900 University Avenue, Riverside, California, 92521
| | - Wensen Jiang
- Materials Science and Engineering Program, University of California at Riverside, 900 University Avenue, Riverside, California, 92521
| | - Huinan Liu
- Materials Science and Engineering Program, University of California at Riverside, 900 University Avenue, Riverside, California, 92521.,Department of Bioengineering, University of California at Riverside, 900 University Avenue, Riverside, California, 92521.,Biomedical Sciences Program, School of Medicine, University of California at Riverside, 900 University Avenue, Riverside, California, 92521.,Stem Cell Center, University of California at Riverside, 900 University Avenue, Riverside, California, 92521
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104
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Spearman BS, Desai VH, Mobini S, McDermott MD, Graham JB, Otto KJ, Judy JW, Schmidt CE. Tissue-Engineered Peripheral Nerve Interfaces. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1701713. [PMID: 37829558 PMCID: PMC10569514 DOI: 10.1002/adfm.201701713] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Research on neural interfaces has historically concentrated on development of systems for the brain; however, there is increasing interest in peripheral nerve interfaces (PNIs) that could provide benefit when peripheral nerve function is compromised, such as for amputees. Efforts focus on designing scalable and high-performance sensory and motor peripheral nervous system interfaces. Current PNIs face several design challenges such as undersampling of signals from the thousands of axons, nerve-fiber selectivity, and device-tissue integration. To improve PNIs, several researchers have turned to tissue engineering. Peripheral nerve tissue engineering has focused on designing regeneration scaffolds that mimic normal nerve extracellular matrix composition, provide advanced microarchitecture to stimulate cell migration, and have mechanical properties like the native nerve. By combining PNIs with tissue engineering, the goal is to promote natural axon regeneration into the devices to facilitate close contact with electrodes; in contrast, traditional PNIs rely on insertion or placement of electrodes into or around existing nerves, or do not utilize materials to actively facilitate axon regeneration. This review presents the state-of-the-art of PNIs and nerve tissue engineering, highlights recent approaches to combine neural-interface technology and tissue engineering, and addresses the remaining challenges with foreign-body response.
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Affiliation(s)
- Benjamin S Spearman
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
| | - Vidhi H Desai
- Department of Electrical and Computer Engineering, The University of Florida, 216 Larsen Hall, 116200, Gainesville, FL 32611-6200
- Nanoscience Institute for Medical and Engineering Technology, The University of Florida, 1041 Center Drive, 116621, Gainesville, FL 32611-6621
| | - Sahba Mobini
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
| | - Matthew D McDermott
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Dr., West Lafayette, IN 47907-2032
| | - James B Graham
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
| | - Kevin J Otto
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
- Nanoscience Institute for Medical and Engineering Technology, The University of Florida, 1041 Center Drive, 116621, Gainesville, FL 32611-6621
- Department of Neuroscience, The University of Florida, 1149 Newell Dr., Room L1-100, 100244, Gainesville, FL 32610-0244
- Department of Neurology, The University of Florida, 2000 SW Archer Rd., Third Floor, 100383, Gainesville, FL 32610
| | - Jack W Judy
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
- Department of Electrical and Computer Engineering, The University of Florida, 216 Larsen Hall, 116200, Gainesville, FL 32611-6200
- Nanoscience Institute for Medical and Engineering Technology, The University of Florida, 1041 Center Drive, 116621, Gainesville, FL 32611-6621
| | - Christine E Schmidt
- Crayton Pruitt Family Department of Biomedical Engineering, The University of Florida, 1275 Center Dr., BMS Building JG-56, 116131, Gainesville, FL 32611-6131
- Nanoscience Institute for Medical and Engineering Technology, The University of Florida, 1041 Center Drive, 116621, Gainesville, FL 32611-6621
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105
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Downs ME, Lee SA, Yang G, Kim S, Wang Q, Konofagou EE. Non-invasive peripheral nerve stimulation via focused ultrasound in vivo. Phys Med Biol 2018; 63:035011. [PMID: 29214985 DOI: 10.1088/1361-6560/aa9fc2] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Focused ultrasound (FUS) has been employed on a wide range of clinical applications to safely and non-invasively achieve desired effects that have previously required invasive and lengthy procedures with conventional methods. Conventional electrical neuromodulation therapies that are applied to the peripheral nervous system (PNS) are invasive and/or non-specific. Recently, focused ultrasound has demonstrated the ability to modulate the central nervous system and ex vivo peripheral neurons. Here, for the first time, noninvasive stimulation of the sciatic nerve eliciting a physiological response in vivo is demonstrated with FUS. FUS was applied on the sciatic nerve in mice with simultaneous electromyography (EMG) on the tibialis anterior muscle. EMG signals were detected during or directly after ultrasound stimulation along with observable muscle contraction of the hind limb. Transecting the sciatic nerve downstream of FUS stimulation eliminated EMG activity during FUS stimulation. Peak-to-peak EMG response amplitudes and latency were found to be comparable to conventional electrical stimulation methods. Histology along with behavioral and thermal testing did not indicate damage to the nerve or surrounding regions. The findings presented herein demonstrate that FUS can serve as a targeted, safe and non-invasive alternative to conventional peripheral nervous system stimulation to treat peripheral neuropathic diseases in the clinic.
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Affiliation(s)
- Matthew E Downs
- Departments of Biomedical Engineering, Columbia University, New York, NY 10032, United States of America
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106
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Ryan AJ, Lackington WA, Hibbitts AJ, Matheson A, Alekseeva T, Stejskalova A, Roche P, O'Brien FJ. A Physicochemically Optimized and Neuroconductive Biphasic Nerve Guidance Conduit for Peripheral Nerve Repair. Adv Healthc Mater 2017; 6. [PMID: 28975768 DOI: 10.1002/adhm.201700954] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Indexed: 11/07/2022]
Abstract
Clinically available hollow nerve guidance conduits (NGCs) have had limited success in treating large peripheral nerve injuries. This study aims to develop a biphasic NGC combining a physicochemically optimized collagen outer conduit to bridge the transected nerve, and a neuroconductive hyaluronic acid-based luminal filler to support regeneration. The outer conduit is mechanically optimized by manipulating crosslinking and collagen density, allowing the engineering of a high wall permeability to mitigate the risk of neuroma formation, while also maintaining physiologically relevant stiffness and enzymatic degradation tuned to coincide with regeneration rates. Freeze-drying is used to seamlessly integrate the luminal filler into the conduit, creating a longitudinally aligned pore microarchitecture. The luminal stiffness is modulated to support Schwann cells, with laminin incorporation further enhancing bioactivity by improving cell attachment and metabolic activity. Additionally, this biphasic NGC is shown to support neurogenesis and gliogenesis of neural progenitor cells and axonal outgrowth from dorsal root ganglia. These findings highlight the paradigm that a successful NGC requires the concerted optimization of both a mechanical support phase capable of bridging a nerve defect and a neuroconductive phase with an architecture capable of supporting both Schwann cells and neurons in order to achieve functional regenerative outcome.
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Affiliation(s)
- Alan J. Ryan
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - William A. Lackington
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - Alan J. Hibbitts
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - Austyn Matheson
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - Tijna Alekseeva
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - Anna Stejskalova
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - Phoebe Roche
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
| | - Fergal J. O'Brien
- Tissue Engineering Research Group (TERG); Department of Anatomy; Royal College of Surgeons in Ireland; Dublin Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre; Trinity College Dublin; Dublin Ireland
- Trinity Centre for Bioengineering (TCBE); Trinity College Dublin; Dublin Ireland
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107
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Qi D, Liu Z, Liu Y, Jiang Y, Leow WR, Pal M, Pan S, Yang H, Wang Y, Zhang X, Yu J, Li B, Yu Z, Wang W, Chen X. Highly Stretchable, Compliant, Polymeric Microelectrode Arrays for In Vivo Electrophysiological Interfacing. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1702800. [PMID: 28869690 DOI: 10.1002/adma.201702800] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/05/2017] [Indexed: 06/07/2023]
Abstract
Polymeric microelectrode arrays (MEAs) are emerging as a new generation of biointegrated microelectrodes to transduce original electrochemical signals in living tissues to external electrical circuits, and vice versa. So far, the challenge of stretchable polymeric MEAs lies in the competition between high stretchability and good electrode-substrate adhesion. The larger the stretchability, the easier the delamination of electrodes from the substrate due to the mismatch in their Young's modulus. In this work, polypyrrole (PPy) electrode materials are designed, with PPy nanowires integrated on the high conductive PPy electrode arrays. By utilizing this electrode material, for the first time, stretchable polymeric MEAs are fabricated with both high stretchability (≈100%) and good electrode-substrate adhesion (1.9 MPa). In addition, low Young's modulus (450 kPa), excellent recycling stability (10 000 cycles of stretch), and high conductivity of the MEAs are also achieved. As a proof of concept, the as-prepared polymeric MEAs are successfully used for conformally recording the electrocorticograph signals from rats in normal and epileptic states, respectively. Further, these polymeric MEAs are also successful in stimulating the ischiadic nerve of the rat. This strategy provides a new perspective to the highly stretchable and mechanically stable polymeric MEAs, which are vital for compliant neural electrodes.
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Affiliation(s)
- Dianpeng Qi
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Zhiyuan Liu
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Yan Liu
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Ying Jiang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Wan Ru Leow
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Mayank Pal
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Shaowu Pan
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Hui Yang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Yu Wang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Xiaoqian Zhang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Jiancan Yu
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Bin Li
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Zhe Yu
- Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen University Town, 1068 Xueyuan Avenue, Shenzhen, 518055, P. R. China
| | - Wei Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, P. R. China
| | - Xiaodong Chen
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
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108
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Neural differentiation of human induced pluripotent stem cells on polycaprolactone/gelatin bi-electrospun nanofibers. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 78:1195-1202. [DOI: 10.1016/j.msec.2017.04.083] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 04/13/2017] [Accepted: 04/15/2017] [Indexed: 01/11/2023]
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109
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Giampetruzzi L, Blasi L, Quarta A, Argentiere S, Cella C, Salvatore L, Madaghiele M, Gigli G, Sannino A. Poly(lactide-co-glycolide) nanoparticles embedded in a micropatterned collagen scaffold for neuronal tissue regeneration. INT J POLYM MATER PO 2017. [DOI: 10.1080/00914037.2016.1217533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Lucia Giampetruzzi
- Istituto Italiano di Tecnologia, Lecce, Italy
- Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Lecce, Italy
| | - Laura Blasi
- CNR NANOTEC - Institute of Nanotechnology, University of Salento, Lecce, Italy
| | - Alessandra Quarta
- CNR NANOTEC - Institute of Nanotechnology, University of Salento, Lecce, Italy
| | | | | | - Luca Salvatore
- Department of Engineering for Innovation, University of Salento, Lecce, Italy
| | - Marta Madaghiele
- Department of Engineering for Innovation, University of Salento, Lecce, Italy
| | - Giuseppe Gigli
- Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Lecce, Italy
- CNR NANOTEC - Institute of Nanotechnology, University of Salento, Lecce, Italy
| | - Alessandro Sannino
- Department of Engineering for Innovation, University of Salento, Lecce, Italy
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110
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Heo DN, Kim HJ, Lee YJ, Heo M, Lee SJ, Lee D, Do SH, Lee SH, Kwon IK. Flexible and Highly Biocompatible Nanofiber-Based Electrodes for Neural Surface Interfacing. ACS NANO 2017; 11:2961-2971. [PMID: 28196320 DOI: 10.1021/acsnano.6b08390] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Polyimide (PI)-based electrodes have been widely used as flexible biosensors in implantable device applications for recording biological signals. However, the long-term quality of neural signals obtained from PI-based nerve electrodes tends to decrease due to nerve damage by neural tissue compression, mechanical mismatch, and insufficient fluid exchange between the neural tissue and electrodes. Here, we resolve these problems with a developed PI nanofiber (NF)-based nerve electrode for stable neural signal recording, which can be fabricated via electrospinning and inkjet printing. We demonstrate an NF-based nerve electrode that can be simply fabricated and easily applied due to its high permeability, flexibility, and biocompatibility. Furthermore, the electrode can record stable neural signals for extended periods of time, resulting in decreased mechanical mismatch, neural compression, and contact area. NF-based electrodes with highly flexible and body-fluid-permeable properties could enable future neural interfacing applications.
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Affiliation(s)
- Dong Nyoung Heo
- Department of Mechanical and Aerospace Engineering, The George Washington University , Washington, DC 20052, United States
- Department of Dental Materials, School of Dentistry, Kyung Hee University , Seoul 02447, Republic of Korea
| | - Han-Jun Kim
- Department of Clinical Pathology, College of Veterinary Medicine, Konkuk University , Seoul 05029, Republic of Korea
| | - Yi Jae Lee
- Center for BioMicroSystems, Korea Institute of Science and Technology , Seoul 02455, Republic of Korea
| | - Min Heo
- Department of Dental Materials, School of Dentistry, Kyung Hee University , Seoul 02447, Republic of Korea
| | - Sang Jin Lee
- Department of Dental Materials, School of Dentistry, Kyung Hee University , Seoul 02447, Republic of Korea
| | - Donghyun Lee
- Department of Dental Materials, School of Dentistry, Kyung Hee University , Seoul 02447, Republic of Korea
| | - Sun Hee Do
- Department of Clinical Pathology, College of Veterinary Medicine, Konkuk University , Seoul 05029, Republic of Korea
| | - Soo Hyun Lee
- Center for BioMicroSystems, Korea Institute of Science and Technology , Seoul 02455, Republic of Korea
| | - Il Keun Kwon
- Department of Dental Materials, School of Dentistry, Kyung Hee University , Seoul 02447, Republic of Korea
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111
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Hsu SH, Chang WC, Yen CT. Novel flexible nerve conduits made of water-based biodegradable polyurethane
for peripheral nerve regeneration. J Biomed Mater Res A 2017; 105:1383-1392. [DOI: 10.1002/jbm.a.36022] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/20/2017] [Accepted: 01/26/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Shan-hui Hsu
- Institute of Polymer Science and Engineering; National Taiwan University; Taipei Taiwan
| | - Wen-Chi Chang
- Institute of Polymer Science and Engineering; National Taiwan University; Taipei Taiwan
| | - Chen-Tung Yen
- Department of Life Science and Institute of Zoology; National Taiwan University; Taipei Taiwan
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112
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Sperling LE, Reis KP, Pozzobon LG, Girardi CS, Pranke P. Influence of random and oriented electrospun fibrous poly(lactic-co
-glycolic acid) scaffolds on neural differentiation of mouse embryonic stem cells. J Biomed Mater Res A 2017; 105:1333-1345. [DOI: 10.1002/jbm.a.36012] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 01/13/2017] [Accepted: 01/19/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Laura E. Sperling
- Hematology and Stem Cell Laboratory, Faculty of Pharmacy; Av. Ipiranga 2752, room 304G, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
- Stem Cell Laboratory, Fundamental Health Science Institute; Rua Sarmento Leite, 500, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
| | - Karina P. Reis
- Hematology and Stem Cell Laboratory, Faculty of Pharmacy; Av. Ipiranga 2752, room 304G, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
- Stem Cell Laboratory, Fundamental Health Science Institute; Rua Sarmento Leite, 500, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
- Post Graduate Program in Physiology, Federal University of Rio Grande do Sul; Porto Alegre RS Brazil
| | - Laura G. Pozzobon
- Hematology and Stem Cell Laboratory, Faculty of Pharmacy; Av. Ipiranga 2752, room 304G, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
- Stem Cell Laboratory, Fundamental Health Science Institute; Rua Sarmento Leite, 500, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
| | - Carolina S. Girardi
- Hematology and Stem Cell Laboratory, Faculty of Pharmacy; Av. Ipiranga 2752, room 304G, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
| | - Patricia Pranke
- Hematology and Stem Cell Laboratory, Faculty of Pharmacy; Av. Ipiranga 2752, room 304G, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
- Stem Cell Laboratory, Fundamental Health Science Institute; Rua Sarmento Leite, 500, Federal University of Rio Grande do Sul Porto Alegre RS Brazil
- Stem Cell Research Institute; Porto Alegre RS Brazil
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113
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Carvalho CR, López-Cebral R, Silva-Correia J, Silva JM, Mano JF, Silva TH, Freier T, Reis RL, Oliveira JM. Investigation of cell adhesion in chitosan membranes for peripheral nerve regeneration. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 71:1122-1134. [DOI: 10.1016/j.msec.2016.11.100] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/13/2016] [Accepted: 11/24/2016] [Indexed: 12/24/2022]
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114
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Love B. Neural Interventions. Biomaterials 2017. [DOI: 10.1016/b978-0-12-809478-5.00012-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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115
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Torregrosa T, Koppes RA. Bioelectric Medicine and Devices for the Treatment of Spinal Cord Injury. Cells Tissues Organs 2016; 202:6-22. [PMID: 27701161 DOI: 10.1159/000446698] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2016] [Indexed: 11/19/2022] Open
Abstract
Recovery of motor control is paramount for patients living with paralysis following spinal cord injury (SCI). While a cure or regenerative intervention remains on the horizon for the treatment of SCI, a number of neuroprosthetic devices have been employed to treat and mitigate the symptoms of paralysis associated with injuries to the spinal column and associated comorbidities. The recent success of epidural stimulation to restore voluntary motor function in the lower limbs of a small cohort of patients has breathed new life into the promise of electric-based medicine. Recently, a number of new organic and inorganic electronic devices have been developed for brain-computer interfaces to bypass the injury, for neurorehabilitation, bladder and bowel control, and the restoration of motor or sensory control. Herein, we discuss the recent advances in neuroprosthetic devices for treating SCI and highlight future design needs for closed-loop device systems.
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116
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Li YJ, Zhao BL, Lv HZ, Qin ZG, Luo M. Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects: biomechanics and validation of mathematical models. Neural Regen Res 2016; 11:1322-6. [PMID: 27651781 PMCID: PMC5020832 DOI: 10.4103/1673-5374.189198] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects. To test this, we established rabbit models of 30 mm sciatic nerve defects, and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells. We compared the tensile properties, electrophysiological function and morphology of the damaged nerve in each group. Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone, and produced similar results to those observed with the autograft. These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.
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Affiliation(s)
- Ya-Jun Li
- School of Mathematics, Jilin University, Changchun, Jilin Province, China
| | - Bao-Lin Zhao
- Department of Orthopedics, China-Japan Union Hospital of Jilin University, Changchun, Jilin Province, China
| | - Hao-Ze Lv
- Department of Clinical Medicine, School of Clinical Medicine, Jilin University, Changchun, Jilin Province, China
| | - Zhi-Gang Qin
- Department of Neurosurgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin Province, China
| | - Min Luo
- Department of Pain, China-Japan Union Hospital of Jilin University, Changchun, Jilin Province, China
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117
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Nawrotek K, Tylman M, Rudnicka K, Gatkowska J, Balcerzak J. Tubular electrodeposition of chitosan–carbon nanotube implants enriched with calcium ions. J Mech Behav Biomed Mater 2016; 60:256-266. [DOI: 10.1016/j.jmbbm.2016.02.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 01/30/2016] [Accepted: 02/05/2016] [Indexed: 01/20/2023]
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118
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Design and manufacture of neural tissue engineering scaffolds using hyaluronic acid and polycaprolactone nanofibers with controlled porosity. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 69:380-7. [PMID: 27612726 DOI: 10.1016/j.msec.2016.06.078] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/22/2016] [Accepted: 06/23/2016] [Indexed: 11/27/2022]
Abstract
Given the large differences in nervous tissue and other tissues of the human body and its unique features, such as poor and/or lack of repair, there are many challenges in the repair process of this tissue. Tissue engineering is one of the most effective approaches to repair neural damages. Scaffolds made from electrospun fibers have special potential in cell adhesion, function and cell proliferation. This research attempted to design a high porous nanofibrous scaffold using hyaluronic acid and polycaprolactone to provide ideal conditions for nerve regeneration by applying proper physicochemical and mechanical signals. Chemical and mechanical properties of pure PCL and PCL/HA nanofibrous scaffolds were measured by FTIR and tensile test. Morphology, swelling behavior, and biodegradability of the scaffolds were evaluated too. Porosity of various layers of scaffolds was measured by image analysis method. To assess the cell-scaffold interaction, SH-SY5Y human neuroblastoma cell line were cultured on the electrospun scaffolds. Taken together, these results suggest that the blended nanofibrous scaffolds PCL/HA 95:5 exhibit the most balanced properties to meet all of the required specifications for neural cells and have potential application in neural tissue engineering.
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Abstract
Manufactured conduits and allografts are viable alternatives to direct suture repair and nerve autograft. Manufactured tubes should have gaps less than 10 mm, and ideally should be considered as an aid to the coaptation. Processed nerve allograft has utility as a substitute for either conduit or autograft in sensory nerve repairs. There is also a growing body of evidence supporting their utility in major peripheral nerve repairs, gap repairs up to 70 mm in length, as an alternative source of tissue to bolster the diameter of a cable graft, and for the management of neuromas in non-reconstructable injuries.
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Affiliation(s)
- Bauback Safa
- The Buncke Clinic, 45 Castro Street #121, San Francisco, CA 94114, USA.
| | - Gregory Buncke
- The Buncke Clinic, 45 Castro Street #121, San Francisco, CA 94114, USA
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120
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Acellularization-Induced Changes in Tensile Properties Are Organ Specific - An In-Vitro Mechanical and Structural Analysis of Porcine Soft Tissues. PLoS One 2016; 11:e0151223. [PMID: 26960134 PMCID: PMC4784745 DOI: 10.1371/journal.pone.0151223] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/23/2016] [Indexed: 12/18/2022] Open
Abstract
Introduction Though xenogeneic acellular scaffolds are frequently used for surgical reconstruction, knowledge of their mechanical properties is lacking. This study compared the mechanical, histological and ultrastructural properties of various native and acellular specimens. Materials and Methods Porcine esophagi, ureters and skin were tested mechanically in a native or acellular condition, focusing on the elastic modulus, ultimate tensile stress and maximum strain. The testing protocol for soft tissues was standardized, including the adaption of the tissue’s water content and partial plastination to minimize material slippage as well as templates for normed sample dimensions and precise cross-section measurements. The native and acellular tissues were compared at the microscopic and ultrastructural level with a focus on type I collagens. Results Increased elastic modulus and ultimate tensile stress values were quantified in acellular esophagi and ureters compared to the native condition. In contrast, these values were strongly decreased in the skin after acellularization. Acellularization-related decreases in maximum strain were found in all tissues. Type I collagens were well-preserved in these samples; however, clotting and a loss of cross-linking type I collagens was observed ultrastructurally. Elastins and fibronectins were preserved in the esophagi and ureters. A loss of the epidermal layer and decreased fibronectin content was present in the skin. Discussion Acellularization induces changes in the tensile properties of soft tissues. Some of these changes appear to be organ specific. Loss of cross-linking type I collagen may indicate increased mechanical strength due to decreasing transverse forces acting upon the scaffolds, whereas fibronectin loss may be related to decreased load-bearing capacity. Potentially, the alterations in tissue mechanics are linked to organ function and to the interplay of cells and the extracellular matrix, which is different in hollow organs when compared to skin.
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121
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Implantable neurotechnologies: a review of micro- and nanoelectrodes for neural recording. Med Biol Eng Comput 2016; 54:23-44. [PMID: 26753777 DOI: 10.1007/s11517-015-1430-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 12/10/2015] [Indexed: 12/22/2022]
Abstract
Electrodes serve as the first critical interface to the biological organ system. In neuroprosthetic applications, for example, electrodes interface to the tissue for either signal recording or tissue stimulation. In this review, we consider electrodes for recording neural activity. Recording electrodes serve as wiretaps into the neural tissues, providing readouts of electrical activity. These signals give us valuable insights into the organization and functioning of the nervous system. The recording interfaces have also shown promise in aiding treatment of motor and sensory disabilities caused by neurological disorders. Recent advances in fabrication technology have generated wide interest in creating tiny, high-density electrode interfaces for neural tissues. An ideal electrode should be small enough and be able to achieve reliable and conformal integration with the structures of the nervous system. As a result, the existing electrode designs are being shrunk and packed to form small form factor interfaces to tissue. Here, an overview of the historic and state-of-the-art electrode technologies for recording neural activity is presented first with a focus on their development road map. The fact that the dimensions of recording electrode sites are being scaled down from micron to submicron scale to enable dense interfaces is appreciated. The current trends in recording electrode technologies are then reviewed. Current and future considerations in electrode design, including the use of inorganic nanostructures and biologically inspired or biocomapatible materials are discussed, along with an overview of the applications of flexible materials and transistor transduction schemes. Finally, we detail the major technical challenges facing chronic use of reliable recording electrode technology.
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122
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Nawrotek K, Tylman M, Rudnicka K, Balcerzak J, Kamiński K. Chitosan-based hydrogel implants enriched with calcium ions intended for peripheral nervous tissue regeneration. Carbohydr Polym 2016; 136:764-71. [DOI: 10.1016/j.carbpol.2015.09.105] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/27/2015] [Accepted: 09/28/2015] [Indexed: 01/30/2023]
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123
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Chen J, Guo B, Eyster TW, Ma PX. Super stretchable electroactive elastomer formation driven by aniline trimer self-assembly. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2015; 27:5668-5677. [PMID: 26692638 PMCID: PMC4674812 DOI: 10.1021/acs.chemmater.5b02086] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Biomedical electroactive elastomers with a modulus similar to that of soft tissues are highly desirable for muscle, nerve, and other soft tissue replacement or regeneration, but have rarely been reported. In this work, superiorly stretchable electroactive polyurethane-urea elastomers were designed based on poly(lactide), poly(ethylene glycol), and aniline trimer (AT). A strain at break higher than 1600% and a modulus close to soft tissues was achieved from these copolymers. The mechanisms of super stretchability of the copolymer were systematically investigated. Crystallinity, chemical cross-linking, ionic cross-linking and hard domain formation were examined using differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), nuclear magnetic resonance (NMR) measurements and transmission electron microscopy (TEM). The sphere-like hard domains self-assembled from AT segments were found to provide the crucial physical interactions needed for the novel super elastic material formation. These super stretchable copolymers were blended with conductive fillers such as polyaniline nanofibers and nanosized carbon black to achieve a high electric conductivity of 0.1 S/cm while maintaining an excellent stretchability and a modulus similar to that of soft tissues (lower than 10 MPa).
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Affiliation(s)
- Jing Chen
- Center for Biomedical Engineering and Regenerative Medicine, Frontier Institute of Science and Technology, Xi’an Jiaotong University, Xi’an, 710049, China
| | - Baolin Guo
- Center for Biomedical Engineering and Regenerative Medicine, Frontier Institute of Science and Technology, Xi’an Jiaotong University, Xi’an, 710049, China
| | - Thomas W. Eyster
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI 48109, USA
| | - Peter X. Ma
- Center for Biomedical Engineering and Regenerative Medicine, Frontier Institute of Science and Technology, Xi’an Jiaotong University, Xi’an, 710049, China
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Macromolecular Science and Engineering Center, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109, USA
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124
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Chronic multichannel neural recordings from soft regenerative microchannel electrodes during gait. Sci Rep 2015; 5:14363. [PMID: 26400791 PMCID: PMC4585830 DOI: 10.1038/srep14363] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 08/24/2015] [Indexed: 11/24/2022] Open
Abstract
Reliably interfacing a nerve with an electrode array is one of the approaches to restore motor and sensory functions after an injury to the peripheral nerve. Accomplishing this with current technologies is challenging as the electrode-neuron interface often degrades over time, and surrounding myoelectric signals contaminate the neuro-signals in awake, moving animals. The purpose of this study was to evaluate the potential of microchannel electrode implants to monitor over time and in freely moving animals, neural activity from regenerating nerves. We designed and fabricated implants with silicone rubber and elastic thin-film metallization. Each implant carries an eight-by-twelve matrix of parallel microchannels (of 120 × 110 μm2 cross-section and 4 mm length) and gold thin-film electrodes embedded in the floor of ten of the microchannels. After sterilization, the soft, multi-lumen electrode implant is sutured between the stumps of the sciatic nerve. Over a period of three months and in four rats, the microchannel electrodes recorded spike activity from the regenerating sciatic nerve. Histology indicates mini-nerves formed of axons and supporting cells regenerate robustly in the implants. Analysis of the recorded spikes and gait kinematics over the ten-week period suggests firing patterns collected with the microchannel electrode implant can be associated with different phases of gait.
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125
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Mechanical properties of a bioabsorbable nerve guide tube for long nerve defects. ACTA ACUST UNITED AC 2015; 34:186-92. [DOI: 10.1016/j.main.2015.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 05/24/2015] [Accepted: 05/27/2015] [Indexed: 11/21/2022]
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126
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Trends in the design of nerve guidance channels in peripheral nerve tissue engineering. Prog Neurobiol 2015; 131:87-104. [DOI: 10.1016/j.pneurobio.2015.06.001] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 06/03/2015] [Accepted: 06/09/2015] [Indexed: 01/01/2023]
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127
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Bober BG, Shah SB. Paclitaxel alters sensory nerve biomechanical properties. J Biomech 2015; 48:3559-67. [PMID: 26321364 DOI: 10.1016/j.jbiomech.2015.07.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/14/2015] [Accepted: 07/18/2015] [Indexed: 11/16/2022]
Abstract
Paclitaxel is an effective chemotherapeutic that, despite its common use, frequently causes debilitating peripheral sensory neuropathy. Paclitaxel binds to and stabilizes microtubules, and through unknown mechanisms, causes abnormal microtubule aggregation. Given that microtubules contribute to the mechanical properties of cells, we tested the hypothesis that paclitaxel treatment would alter the stiffness of sensory nerves. Rat sural nerves were excised and soaked in Ringer's solution with or without paclitaxel. Nerves were secured between a force transducer and actuator, and linearly strained. Stress-strain curves were generated, from which elastic moduli were calculated. Paclitaxel treated nerves exhibited significantly higher moduli in both linear and transition regions of the curve. A composite-tissue model was then generated to estimate the stiffness increase in the cellular fraction of the nerve following paclitaxel treatment. This model was supported experimentally by data on mechanical properties of sural nerves stripped of their epineurium, and area fractions of the cellular and connective tissue components of the rat sural nerve, calculated from immunohistochemical images. Model results revealed that the cellular components of the nerve must stiffen 12x to 115x, depending on the initial axonal modulus assumed, in order to achieve the observed tissue level mechanical changes. Consistent with such an increase, electron microscopy showed increased microtubule aggregation and cytoskeletal packing, suggestive of a more cross-linked cytoskeleton. Overall, our data suggests that paclitaxel treatment induces increased microtubule bundling in axons, which leads to alterations in tissue-level mechanical properties.
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Affiliation(s)
- Brian G Bober
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
| | - Sameer B Shah
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA; Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, USA.
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128
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Zilic L, Garner PE, Yu T, Roman S, Haycock JW, Wilshaw SP. An anatomical study of porcine peripheral nerve and its potential use in nerve tissue engineering. J Anat 2015. [PMID: 26200940 PMCID: PMC4560565 DOI: 10.1111/joa.12341] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Current nerve tissue engineering applications are adopting xenogeneic nerve tissue as potential nerve grafts to help aid nerve regeneration. However, there is little literature that describes the exact location, anatomy and physiology of these nerves to highlight their potential as a donor graft. The aim of this study was to identify and characterise the structural and extracellular matrix (ECM) components of porcine peripheral nerves in the hind leg. Methods included the dissection of porcine nerves, localisation, characterisation and quantification of the ECM components and identification of nerve cells. Results showed a noticeable variance between porcine and rat nerve (a commonly studied species) in terms of fascicle number. The study also revealed that when porcine peripheral nerves branch, a decrease in fascicle number and size was evident. Porcine ECM and nerve fascicles were found to be predominately comprised of collagen together with glycosaminoglycans, laminin and fibronectin. Immunolabelling for nerve growth factor receptor p75 also revealed the localisation of Schwann cells around and inside the fascicles. In conclusion, it is shown that porcine peripheral nerves possess a microstructure similar to that found in rat, and is not dissimilar to human. This finding could extend to the suggestion that due to the similarities in anatomy to human nerve, porcine nerves may have utility as a nerve graft providing guidance and support to regenerating axons.
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Affiliation(s)
- Leyla Zilic
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - Philippa E Garner
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Tong Yu
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - Sabiniano Roman
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - John W Haycock
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - Stacy-Paul Wilshaw
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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129
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Lizarraga-Valderrama LR, Nigmatullin R, Taylor C, Haycock JW, Claeyssens F, Knowles JC, Roy I. Nerve tissue engineering using blends of poly(3-hydroxyalkanoates) for peripheral nerve regeneration. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400151] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Affiliation(s)
- Lorena R. Lizarraga-Valderrama
- Applied Biotechnology Research Group; Department of Life Sciences; Faculty of Science and Technology; University of Westminster; London UK
| | - Rinat Nigmatullin
- Applied Biotechnology Research Group; Department of Life Sciences; Faculty of Science and Technology; University of Westminster; London UK
| | - Caroline Taylor
- Department of Materials Science and Engineering; Kroto Research Institute; Sheffield UK
| | - John W. Haycock
- Department of Materials Science and Engineering; Kroto Research Institute; Sheffield UK
| | - Frederik Claeyssens
- Department of Materials Science and Engineering; Kroto Research Institute; Sheffield UK
| | - Jonathan C. Knowles
- Division of Biomaterials and Tissue Engineering; UCL Eastman Dental Institute; London UK
- Department of Nanobiomedical Science, BK21 Plus NBM Global Research Center for Regenerative Medicine; Dankook University; Cheonan Republic of Korea
| | - Ipsita Roy
- Applied Biotechnology Research Group; Department of Life Sciences; Faculty of Science and Technology; University of Westminster; London UK
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130
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Pateman CJ, Harding AJ, Glen A, Taylor CS, Christmas CR, Robinson PP, Rimmer S, Boissonade FM, Claeyssens F, Haycock JW. Nerve guides manufactured from photocurable polymers to aid peripheral nerve repair. Biomaterials 2015; 49:77-89. [DOI: 10.1016/j.biomaterials.2015.01.055] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 12/21/2014] [Accepted: 01/20/2015] [Indexed: 12/24/2022]
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131
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Silk-tropoelastin protein films for nerve guidance. Acta Biomater 2015; 14:1-10. [PMID: 25481743 DOI: 10.1016/j.actbio.2014.11.045] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 11/16/2014] [Accepted: 11/24/2014] [Indexed: 12/24/2022]
Abstract
Peripheral nerve regeneration may be enhanced through the use of biodegradable thin film biomaterials as highly tuned inner nerve conduit liners. Dorsal root ganglion neuron and Schwann cell responses were studied on protein films comprising silk fibroin blended with recombinant human tropoelastin protein. Tropoelastin significantly improved neurite extension and enhanced Schwann cell process length and cell area, while the silk provided a robust biomaterial template. Silk-tropoelastin blends afforded a 2.4-fold increase in neurite extension, when compared to silk films coated with poly-d-lysine. When patterned by drying on grooved polydimethylsiloxane (3.5 μm groove width, 0.5 μm groove depth), these protein blends induced both neurite and Schwann cell process alignment. Neurons were functional as assessed using patch-clamping, and displayed action potentials similar to those cultured on poly(lysine)-coated glass. Taken together, silk-tropoelastin films offer useful biomaterial interfacial platforms for nerve cell control, which can be considered for neurite guidance, disease models for neuropathies and surgical peripheral nerve repairs.
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132
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Williams MJ, Utzinger U, Barkmeier-Kraemer JM, Vande Geest JP. Differences in the microstructure and biomechanical properties of the recurrent laryngeal nerve as a function of age and location. J Biomech Eng 2015; 136:1873195. [PMID: 24829083 DOI: 10.1115/1.4027682] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 05/15/2014] [Indexed: 11/08/2022]
Abstract
Idiopathic onset of unilateral vocal fold paralysis (UVP) is caused by damage to the recurrent laryngeal nerve (RLN) and results in difficulty speaking, breathing, and swallowing. This damage may occur in this nerve as it loops around the aortic arch, which is in a dynamic biomechanical environment. The goal of this study is to determine if the location-dependent biomechanical and microstructural properties of the RLN are different in piglets versus adolescent pigs. The neck/distal and thoracic/proximal (near the aortic arch) regions of the RLN from eight adolescent pigs and six piglets were isolated and mechanically assessed in uni-axial tension. Two-photon imaging (second harmonic) data were collected at 5%, 10%, and 15% strain during the mechanical test. The tangential modulus (TM) and the strain energy density (W) were determined at each level of strain. The mean mode of the preferred fiber angle and the full width at half maximum (FWHM, a measure of fiber splay) were calculated from the imaging data. We found significantly larger values of TM, W, and FWHM in the proximal segments of the left RLN when compared to the distal segments (18.51 MPa ± 1.22 versus 10.78 MPa ± 1.22, p < 0.001 for TM, 0.046 MPa ± 0.01 versus 0.026 MPa ± 0.01, p < 0.003 for W, 15.52 deg ± 1.00 versus 12.98 deg ± 1.00, p < 0.001 for FWHM). TM and W were larger in the left segments than the right (15.32 MPa ± 1.20 versus 11.80 MPa ± 1.20, p < 0.002 for TM, 0.038 MPa ± 0.01 versus 0.028 MPa ± 0.01, p < 0.0001 for W). W was larger in piglets when compared to adolescent pigs (0.042 MPa ± 0.01 versus 0.025 MPa ± 0.01, p < 0.04). The proximal region of the left porcine RLN is more stiff than the distal region and has a higher degree of fiber splay. The left RLN of the adolescent pigs also displayed a higher degree of strain stiffening than the right. These differences may develop as a result of the more dynamic environment the left RLN is in as it loops around the aortic arch.
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133
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Multifunctional fibers for simultaneous optical, electrical and chemical interrogation of neural circuits in vivo. Nat Biotechnol 2015; 33:277-84. [PMID: 25599177 DOI: 10.1038/nbt.3093] [Citation(s) in RCA: 342] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 11/10/2014] [Indexed: 12/19/2022]
Abstract
Brain function depends on simultaneous electrical, chemical and mechanical signaling at the cellular level. This multiplicity has confounded efforts to simultaneously measure or modulate these diverse signals in vivo. Here we present fiber probes that allow for simultaneous optical stimulation, neural recording and drug delivery in behaving mice with high resolution. These fibers are fabricated from polymers by means of a thermal drawing process that allows for the integration of multiple materials and interrogation modalities into neural probes. Mechanical, electrical, optical and microfluidic measurements revealed high flexibility and functionality of the probes under bending deformation. Long-term in vivo recordings, optogenetic stimulation, drug perturbation and analysis of tissue response confirmed that our probes can form stable brain-machine interfaces for at least 2 months. We expect that our multifunctional fibers will permit more detailed manipulation and analysis of neural circuits deep in the brain of behaving animals than achievable before.
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135
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Pashaie R, Anikeeva P, Lee JH, Prakash R, Yizhar O, Prigge M, Chander D, Richner TJ, Williams J. Optogenetic brain interfaces. IEEE Rev Biomed Eng 2014; 7:3-30. [PMID: 24802525 DOI: 10.1109/rbme.2013.2294796] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The brain is a large network of interconnected neurons where each cell functions as a nonlinear processing element. Unraveling the mysteries of information processing in the complex networks of the brain requires versatile neurostimulation and imaging techniques. Optogenetics is a new stimulation method which allows the activity of neurons to be modulated by light. For this purpose, the cell-types of interest are genetically targeted to produce light-sensitive proteins. Once these proteins are expressed, neural activity can be controlled by exposing the cells to light of appropriate wavelengths. Optogenetics provides a unique combination of features, including multimodal control over neural function and genetic targeting of specific cell-types. Together, these versatile features combine to a powerful experimental approach, suitable for the study of the circuitry of psychiatric and neurological disorders. The advent of optogenetics was followed by extensive research aimed to produce new lines of light-sensitive proteins and to develop new technologies: for example, to control the distribution of light inside the brain tissue or to combine optogenetics with other modalities including electrophysiology, electrocorticography, nonlinear microscopy, and functional magnetic resonance imaging. In this paper, the authors review some of the recent advances in the field of optogenetics and related technologies and provide their vision for the future of the field.
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136
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Hopley EL, Salmasi S, Kalaskar DM, Seifalian AM. Carbon nanotubes leading the way forward in new generation 3D tissue engineering. Biotechnol Adv 2014; 32:1000-14. [DOI: 10.1016/j.biotechadv.2014.05.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 05/03/2014] [Accepted: 05/13/2014] [Indexed: 01/25/2023]
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137
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Mouzakis DE, Rachiotis G, Zaoutsos S, Eleftheriou A, Malizos KN. Finite element simulation of the mechanical impact of computer work on the carpal tunnel syndrome. J Biomech 2014; 47:2989-94. [DOI: 10.1016/j.jbiomech.2014.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 07/01/2014] [Accepted: 07/04/2014] [Indexed: 01/03/2023]
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138
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Holberg C, Rudzki-Janson I, Wichelhaus A, Winterhalder P. Periodontal ligament strain induced by different orthodontic bracket removal techniques: nonlinear finite-element comparison study. J Orofac Orthop 2014; 75:287-98. [PMID: 25052508 DOI: 10.1007/s00056-014-0219-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 11/05/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The goal of this work was to biomechanically analyze several different methods of bracket debonding and compare the strain they induce in the periodontal ligament (PDL). METHODS The CT dataset of an anatomical specimen was divided into four segmental models of the mandible. Each model covered one tooth (32, 42, 44, and 47). One of these teeth (32) was characterized by marked loss of periodontal attachment. After suitable finite-element models were generated, material properties were defined as nonlinear for PDL and anisotropic for the alveolar bone. This was followed by simulating four bracket debonding techniques: frontal and lateral torquing, bracket-wing compression, and shear stress applied with specially designed pliers. RESULTS The greatest strain was measured at the periodontally compromised tooth site 32 in response to frontal and lateral torquing. Both techniques also resulted in great strain around the other three teeth. Strain was markedly lower with the shear technique and virtually negligible with the compression technique. All simulated tooth sites confirmed the PDL-sparing effect of bracket-wing compression. CONCLUSION The severity of PDL strain during orthodontic bracket removal depends on the debonding method used. The technique of compressing the bracket wings appears to trigger the smallest effect on PDL. Clinical studies should be undertaken to confirm these findings.
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Affiliation(s)
- Christof Holberg
- Faculty of Medicine, Ludwig-Maximilians-University, Geschwister-Scholl-Platz 1, 80539, Munich, Germany,
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139
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Hess-Dunning AE, Smith RL, Zorman CA. Development of polynorbornene as a structural material for microfluidics and flexible BioMEMS. J Appl Polym Sci 2014. [DOI: 10.1002/app.40969] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Allison E. Hess-Dunning
- Rehabilitation Research and Development; Advanced Platform Technology Center of Excellence, Louis Stokes Cleveland VA Medical Center; Cleveland Ohio 44106
| | - Russell L. Smith
- Department of Electrical Engineering and Computer Science; Case Western Reserve University; Cleveland Ohio 44016
| | - Christian A. Zorman
- Rehabilitation Research and Development; Advanced Platform Technology Center of Excellence, Louis Stokes Cleveland VA Medical Center; Cleveland Ohio 44106
- Department of Electrical Engineering and Computer Science; Case Western Reserve University; Cleveland Ohio 44016
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140
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Hinüber C, Chwalek K, Pan-Montojo FJ, Nitschke M, Vogel R, Brünig H, Heinrich G, Werner C. Hierarchically structured nerve guidance channels based on poly-3-hydroxybutyrate enhance oriented axonal outgrowth. Acta Biomater 2014; 10:2086-95. [PMID: 24406197 DOI: 10.1016/j.actbio.2013.12.053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 12/07/2013] [Accepted: 12/26/2013] [Indexed: 01/19/2023]
Abstract
Traumatic peripheral nerve lesions can cause local anesthesia, paralysis and loss of autonomic control. Reconstruction using engineered nerve guidance conduits (NGCs) is rarely successful due to the sub-optimal characteristics of the conduits. To address the demands of clinical practice, we developed a hierarchically structured NGC from slowly resorbing poly(3-hydroxybutyric acid) (P3HB). The NGC consists of a permeable single-lumen tube and melt-spun fibrillar lumen fillers. Permeable tubes were constructed from P3HB/poly(ɛ-caprolactone) (PCL) blends or poly(3-hydroxybutyric acid-co-4-hydroxybutyric acid) (P(3HB-co-4HB)). Polyvinylpyrrolidone was used as a porogen in solvent-free thermoplastic processing, followed by selective polymer leaching. All tested material compositions showed hydrolytic degradation after 16weeks in phosphate buffered saline, whereas P3HB/PCL tubes maintained mechanical strength compared to (P(3HB-co-4HB)). The porous scaffolds allowed diffusion of large molecules (∼70kDa). In vitro studies demonstrated that mouse fibroblasts survived and proliferated inside closed porous tubes. An in vitro model of axonal regeneration using dorsal root ganglia and sympathetic cervical ganglia demonstrated that the NGCs successfully supported neuron survival and neurite outgrowth. The introduction of fibrillar lumen fillers promoted oriented neurite growth and coating with extracellular matrix proteins further increased ganglia attachment and cell migration. In this study we show that P3HB-based NGCs scaffolds have potential in long gap peripheral nerve repair strategies.
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Affiliation(s)
- C Hinüber
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany; Technische Universität Dresden, Institute of Material Science, Helmholtzstrasse 7, 01069 Dresden, Germany.
| | - K Chwalek
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany
| | - F J Pan-Montojo
- Technische Universität Dresden, Institute of Anatomy/University Hospital Carl Gustav Carus, Fetscherstr. 74, 01307 Dresden, Germany
| | - M Nitschke
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany
| | - R Vogel
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany
| | - H Brünig
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany
| | - G Heinrich
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany; Technische Universität Dresden, Institute of Material Science, Helmholtzstrasse 7, 01069 Dresden, Germany
| | - C Werner
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany; Technische Universität Dresden, Center for Regenerative Therapies Dresden, Tatzberg 47, 01187 Dresden, Germany
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141
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Kijeńska E, Prabhakaran MP, Swieszkowski W, Kurzydlowski KJ, Ramakrishna S. Interaction of Schwann cells with laminin encapsulated PLCL core–shell nanofibers for nerve tissue engineering. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2013.10.021] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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142
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Fracture risk of lithium-disilicate ceramic inlays: A finite element analysis. Dent Mater 2013; 29:1244-50. [PMID: 24119917 DOI: 10.1016/j.dental.2013.09.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Revised: 03/01/2013] [Accepted: 09/18/2013] [Indexed: 11/22/2022]
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143
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Influence of Glutamic Acid on the Properties of Poly(xylitol glutamate sebacate) Bioelastomer. Polymers (Basel) 2013. [DOI: 10.3390/polym5041339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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144
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Carbon nanomaterials for nerve tissue stimulation and regeneration. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013; 34:35-49. [PMID: 24268231 DOI: 10.1016/j.msec.2013.09.038] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 09/11/2013] [Accepted: 09/28/2013] [Indexed: 01/25/2023]
Abstract
Nanotechnology offers new perspectives in the field of innovative medicine, especially for reparation and regeneration of irreversibly damaged or diseased nerve tissues due to lack of effective self-repair mechanisms in the peripheral and central nervous systems (PNS and CNS, respectively) of the human body. Carbon nanomaterials, due to their unique physical, chemical and biological properties, are currently considered as promising candidates for applications in regenerative medicine. This chapter discusses the potential applications of various carbon nanomaterials including carbon nanotubes, nanofibers and graphene for regeneration and stimulation of nerve tissue, as well as in drug delivery systems for nerve disease therapy.
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145
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Khatam H, Ravi-Chandar K. On the Evaluation of the Elastic Modulus of Soft Materials Using Beams with Unknown Initial Curvature. STRAIN 2013; 49:420-430. [PMID: 24159244 PMCID: PMC3804344 DOI: 10.1111/str.12048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A nonlinear optimization procedure is established to determine the elastic modulus of slender, soft materials using beams with unknown initial curvature in the presence of large rotations. Specifically, the deflection of clamped-free beams under self-weight - measured at different orientations with respect to gravity - is used to determine the modulus of elasticity and the intrinsic curvature in the unloaded state. The approach is validated with experiments on a number of different materials - steel, polyetherimide, rubber and pig skin. Since the loading is limited to self-weight, the strain levels attained in these tests are small enough to assume a linear elastic material behavior. This nondestructive methodology is also applicable to engineered tissues and extremely delicate materials in order to obtain a quick estimate of the material's elastic modulus.
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146
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Tran RT, Choy WM, Cao H, Qattan I, Chiao JC, Ip WY, Yeung KWK, Yang J. Fabrication and characterization of biomimetic multichanneled crosslinked-urethane-doped polyester tissue engineered nerve guides. J Biomed Mater Res A 2013; 102:2793-804. [PMID: 24115502 DOI: 10.1002/jbm.a.34952] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/05/2013] [Accepted: 09/06/2013] [Indexed: 01/06/2023]
Abstract
Biomimetic scaffolds that replicate the native architecture and mechanical properties of target tissues have been recently shown to be a very promising strategy to guide cellular growth and facilitate tissue regeneration. In this study, porous, soft, and elastic crosslinked urethane-doped polyester (CUPE) tissue engineered nerve guides were fabricated with multiple longitudinally oriented channels and an external non-porous sheath to mimic the native endoneurial microtubular and epineurium structure, respectively. The fabrication technique described herein is highly adaptable and allows for fine control over the resulting nerve guide architecture in terms of channel number, channel diameter, porosity, and mechanical properties. Biomimetic multichanneled CUPE guides were fabricated with various channel numbers and displayed an ultimate peak stress of 1.38 ± 0.22 MPa with a corresponding elongation at break of 122.76 ± 42.17%, which were comparable to that of native nerve tissue. The CUPE nerve guides were also evaluated in vivo for the repair of a 1 cm rat sciatic nerve defect. Although histological evaluations revealed collapse of the inner structure from CUPE TENGs, the CUPE nerve guides displayed fiber populations and densities comparable with nerve autograft controls after 8 weeks of implantation. These studies are the first report of a CUPE-based biomimetic multichanneled nerve guide and warrant future studies towards optimization of the channel geometry for use in neural tissue engineering.
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Affiliation(s)
- Richard T Tran
- Department of Bioengineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802
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147
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Ma Z, Hu S, Tan JS, Myer C, Njus NM, Xia Z. In vitroandin vivomechanical properties of human ulnar and median nerves. J Biomed Mater Res A 2013; 101:2718-25. [DOI: 10.1002/jbm.a.34573] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 12/12/2012] [Accepted: 12/17/2012] [Indexed: 11/12/2022]
Affiliation(s)
| | | | - Juay Seng Tan
- Department of Biomedical Engineering; University of Akron; Akron; Ohio 44325
| | | | - Nina M. Njus
- Summit Hand Center; Summa Health System; Akron; Ohio 44333
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148
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Ceramic inlays: Is the inlay thickness an important factor influencing the fracture risk? J Dent 2013; 41:628-35. [DOI: 10.1016/j.jdent.2013.04.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/19/2013] [Accepted: 04/20/2013] [Indexed: 11/20/2022] Open
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149
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Mobasseri SA, Terenghi G, Downes S. Micro-structural geometry of thin films intended for the inner lumen of nerve conduits affects nerve repair. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2013; 24:1639-47. [PMID: 23572143 DOI: 10.1007/s10856-013-4922-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 03/24/2013] [Indexed: 05/10/2023]
Abstract
Damage to peripheral nerves can cause significant motor or sensory injuries. In serious cases, a nerve is sacrificed from another part of the body to repair a damaged nerve (autograft). The development of biodegradable polymer conduits may offer an alternative to autografts. This study investigated the surface topography and mechanical properties of smooth, pitted and grooved structures of ultra-thin poly (ε-caprolactone)/poly lactic acid blended, solvent-cast films. We have investigated the effect of the groove shape on cell morphology and alignment. Photolithography and dry/wet etching was used to develop patterned silicon substrates with grooves with accurate geometries (V shaped, sloped walls and square shaped). Using a neural cell line (NG108-15), in vitro experiments confirmed good cell attachment and proliferation on all the polymer scaffolds. Imaging techniques demonstrated that there was different cellular responses and morphology according to the shape of the groove. Studies showed that the geometry, particularly the angle of the slope and the space between grooves, affected cellular responses. In addition, biomechanical studies showed that the patterned films had excellent mechanical properties and were stronger than the natural nerve. The conduit tubes were made by rolling the films around a mandrel and using a thermal welding technique to join the edges. The promising biomechanical and in vitro results demonstrate that nerve cell responses are affected by the shape of longitudinal grooves, and particularly by the angle of the slope of the groove walls.
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Affiliation(s)
- S A Mobasseri
- Materials Science Centre, School of Engineering and Physical Sciences, The University of Manchester, Manchester, UK.
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150
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Arslantunali D, Budak G, Hasirci V. Multiwalled CNT-pHEMA composite conduit for peripheral nerve repair. J Biomed Mater Res A 2013; 102:828-41. [PMID: 23554154 DOI: 10.1002/jbm.a.34727] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 03/12/2013] [Accepted: 03/14/2013] [Indexed: 11/08/2022]
Abstract
A nerve conduit is designed to improve peripheral nerve regeneration by providing guidance to the nerve cells. Conductivity of such guides is reported to enhance this process. In the current study, a nerve guide was constructed from poly(2-hydroxyethyl methacrylate) (pHEMA), which was loaded with multiwalled carbon nanotubes (mwCNT) to introduce conductivity. PHEMA hydrogels were designed to have a porous structure to facilitate the transportation of the compounds needed for cell nutrition and growth and also for waste removal. We showed that when loaded with relatively high concentrations of mwCNTs (6%, w/w in hydrogels), the pHEMA guide was more conductive and more hydrophobic than pristine pHEMA hydrogel. The mechanical properties of the composites were better when they carried mwCNT. Elastic modulus of 6% mwCNT loaded pHEMA was twofold higher (0.32 ± 0.06 MPa) and similar to that of the soft tissues. Electrical conductivity was significantly improved (11.4-fold) from 7 × 10(-3) Ω(-1).cm(-1) (pHEMA) to 8.0 × 10(-2) Ω(-1).cm(-1) (6% mwCNT loaded pHEMA). On application of electrical potential, the SHSY5Y neuroblastoma cells seeded on mwCNTs carrying pHEMA maintained their viability, whereas those on pure pHEMA could not, indicating that mwCNT helped conduct electricity and make them more suitable as nerve conduits.
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Affiliation(s)
- D Arslantunali
- BIOMATEN, METU Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey; Department of Biotechnology, METU, Ankara, Turkey; Department of Bioengineering, Gümüşhane University, Gümüşhane, Turkey
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