101
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Tam WK, Wu T, Zhao Q, Keefer E, Yang Z. Human motor decoding from neural signals: a review. BMC Biomed Eng 2019; 1:22. [PMID: 32903354 PMCID: PMC7422484 DOI: 10.1186/s42490-019-0022-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 07/21/2019] [Indexed: 01/24/2023] Open
Abstract
Many people suffer from movement disability due to amputation or neurological diseases. Fortunately, with modern neurotechnology now it is possible to intercept motor control signals at various points along the neural transduction pathway and use that to drive external devices for communication or control. Here we will review the latest developments in human motor decoding. We reviewed the various strategies to decode motor intention from human and their respective advantages and challenges. Neural control signals can be intercepted at various points in the neural signal transduction pathway, including the brain (electroencephalography, electrocorticography, intracortical recordings), the nerves (peripheral nerve recordings) and the muscles (electromyography). We systematically discussed the sites of signal acquisition, available neural features, signal processing techniques and decoding algorithms in each of these potential interception points. Examples of applications and the current state-of-the-art performance were also reviewed. Although great strides have been made in human motor decoding, we are still far away from achieving naturalistic and dexterous control like our native limbs. Concerted efforts from material scientists, electrical engineers, and healthcare professionals are needed to further advance the field and make the technology widely available in clinical use.
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Affiliation(s)
- Wing-kin Tam
- Department of Biomedical Engineering, University of Minnesota Twin Cities, 7-105 Hasselmo Hall, 312 Church St. SE, Minnesota, 55455 USA
| | - Tong Wu
- Department of Biomedical Engineering, University of Minnesota Twin Cities, 7-105 Hasselmo Hall, 312 Church St. SE, Minnesota, 55455 USA
| | - Qi Zhao
- Department of Computer Science and Engineering, University of Minnesota Twin Cities, 4-192 Keller Hall, 200 Union Street SE, Minnesota, 55455 USA
| | - Edward Keefer
- Nerves Incorporated, Dallas, TX P. O. Box 141295 USA
| | - Zhi Yang
- Department of Biomedical Engineering, University of Minnesota Twin Cities, 7-105 Hasselmo Hall, 312 Church St. SE, Minnesota, 55455 USA
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102
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Arafat MA, Rubin LN, Jefferys JGR, Irazoqui PP. A Method of Flexible Micro-Wire Electrode Insertion in Rodent for Chronic Neural Recording and a Device for Electrode Insertion. IEEE Trans Neural Syst Rehabil Eng 2019; 27:1724-1731. [DOI: 10.1109/tnsre.2019.2932032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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103
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Jia Y, Mirbozorgi SA, Zhang P, Inan OT, Li W, Ghovanloo M. A Dual-Band Wireless Power Transmission System for Evaluating mm-Sized Implants. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2019; 13:595-607. [PMID: 31071052 PMCID: PMC6728165 DOI: 10.1109/tbcas.2019.2915649] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Distributed neural interfaces made of many mm-sized implantable medical devices (IMDs) are poised to play a key role in future brain-computer interfaces because of less damage to the surrounding tissue. Evaluating them wirelessly at preclinical stage (e.g., in a rodent model), however, is a major challenge due to weak coupling and significant losses, resulting in limited power delivery to the IMD within a nominal experimental arena, like a homecage, without surpassing the specific absorption rate limit. To address this problem, we present a dual-band EnerCage system with two multi-coil inductive links, which first deliver power at 13.56 MHz from the EnerCage (46 × 24 × 20 cm3) to a headstage (18 × 18 × 15 mm3, 4.8 g) that is carried by the animal via a 4-coil inductive link. Then, a 60 MHz 3-coil inductive link from the headstage powers up the small IMD (2.5 × 2.5 × 1.5 mm3, 15 mg), which in this case is a free floating, wirelessly powered, implantable optical stimulator (FF-WIOS). The power transfer efficiency and power delivered to the load (PDL) from EnerCage to the headstage at 7 cm height were 14.9%-22.7% and 122 mW; and from headstage to FF-WIOS at 5 mm depth were 18% and 2.7 mW, respectively. Bidirectional data connectivity between EnerCage-headstage was established via bluetooth low energy. Between headstage and FF-WIOS, on-off keying and load-shift-keying were used for downlink and uplink data, respectively. Moreover, a closed-loop power controller stabilized PDL to both the headstage and the FF-WIOS against misalignments.
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104
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Jia Y, Mirbozorgi SA, Lee B, Khan W, Madi F, Inan OT, Weber A, Li W, Ghovanloo M. A mm-Sized Free-Floating Wirelessly Powered Implantable Optical Stimulation Device. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2019; 13:608-618. [PMID: 31135371 PMCID: PMC6707363 DOI: 10.1109/tbcas.2019.2918761] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This paper presents a mm-sized, free-floating, wirelessly powered, implantable optical stimulation (FF-WIOS) device for untethered optogenetic neuromodulation. A resonator-based three-coil inductive link creates a homogeneous magnetic field that continuously delivers sufficient power (>2.7 mW) at an optimal carrier frequency of 60 MHz to the FF-WIOS in the near field without surpassing the specific absorption rate limit, regardless of the position of the FF-WIOS in a large brain area. Forward data telemetry carries stimulation parameters by on-off-keying the power carrier at a data rate of 50 kb/s to selectively activate a 4 × 4 μLED array. Load-shift-keying back telemetry controls the wireless power transmission by reporting the FF-WIOS received power level in a closed-loop power control mechanism. LEDs typically require high instantaneous power to emit sufficient light for optical stimulation. Thus, a switched-capacitor-based stimulation architecture is used as an energy storage buffer with one off-chip capacitor to receive charge directly from the inductive link and deliver it to the selected μLED at the onset of stimulation. The FF-WIOS system-on-a-chip prototype, fabricated in a 0.35-μm standard CMOS process, charges a 10-μF capacitor up to 5 V with 37% efficiency and passes instantaneous current spikes up to 10 mA in the selected μLED, creating a bright exponentially decaying flash with minimal wasted power. An in vivo experiment was conducted to verify the efficacy of the FF-WIOS by observing light-evoked local field potentials and immunostained tissue response from the primary visual cortex (V1) of two anesthetized rats.
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105
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Hermann JK, Capadona JR. Understanding the Role of Innate Immunity in the Response to Intracortical Microelectrodes. Crit Rev Biomed Eng 2019; 46:341-367. [PMID: 30806249 DOI: 10.1615/critrevbiomedeng.2018027166] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Intracortical microelectrodes exhibit enormous potential for researching the nervous system, steering assistive devices and functional electrode stimulation systems for severely paralyzed individuals, and augmenting the brain with computing power. Unfortunately, intracortical microelectrodes often fail to consistently record signals over clinically useful periods. Biological mechanisms, such as the foreign body response to intracortical microelectrodes and self-perpetuating neuroinflammatory cascades, contribute to the inconsistencies and decline in recording performance. Unfortunately, few studies have directly correlated microelectrode performance with the neuroinflammatory response to the implanted devices. However, of those select studies that have, the role of the innate immune system remains among the most likely links capable of corroborating the results of different studies, across laboratories. Therefore, the overall goal of this review is to highlight the role of innate immunity signaling in the foreign body response to intracortical microelectrodes and hypothesize as to appropriate strategies that may become the most relevant in enabling brain-dwelling electrodes of any geometry, or location, for a range of clinical applications.
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Affiliation(s)
- John K Hermann
- Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Wickenden Bldg, Cleveland, OH 44106; Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland VA Medical Center, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106-1702
| | - Jeffrey R Capadona
- Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Wickenden Bldg, Cleveland, OH 44106; Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland VA Medical Center, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106-1702
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106
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Singh RK, Occelli LM, Binette F, Petersen-Jones SM, Nasonkin IO. Transplantation of Human Embryonic Stem Cell-Derived Retinal Tissue in the Subretinal Space of the Cat Eye. Stem Cells Dev 2019; 28:1151-1166. [PMID: 31210100 PMCID: PMC6708274 DOI: 10.1089/scd.2019.0090] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
To develop biological approaches to restore vision, we developed a method of transplanting stem cell-derived retinal tissue into the subretinal space of a large-eye animal model (cat). Human embryonic stem cells (hESC) were differentiated to retinal organoids in a dish. hESC-derived retinal tissue was introduced into the subretinal space of wild-type cats following a pars plana vitrectomy. The cats were systemically immunosuppressed with either prednisolone or prednisolone plus cyclosporine A. The eyes were examined by fundoscopy and spectral-domain optical coherence tomography imaging for adverse effects due to the presence of the subretinal grafts. Immunohistochemistry was done with antibodies to retinal and human markers to delineate graft survival, differentiation, and integration into cat retina. We successfully delivered hESC-derived retinal tissue into the subretinal space of the cat eye. We observed strong infiltration of immune cells in the graft and surrounding tissue in the cats treated with prednisolone. In contrast, we showed better survival and low immune response to the graft in cats treated with prednisolone plus cyclosporine A. Immunohistochemistry with antibodies (STEM121, CALB2, DCX, and SMI-312) revealed large number of graft-derived fibers connecting the graft and the host. We also show presence of human-specific synaptophysin puncta in the cat retina. This work demonstrates feasibility of engrafting hESC-derived retinal tissue into the subretinal space of large-eye animal models. Transplanting retinal tissue in degenerating cat retina will enable rapid development of preclinical in vivo work focused on vision restoration.
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Affiliation(s)
- Ratnesh K Singh
- Lineage Cell Therapeutics, Inc. (formerly BioTime Inc.), Carlsbad, California
| | - Laurence M Occelli
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lasing, Michigan
| | - Francois Binette
- Lineage Cell Therapeutics, Inc. (formerly BioTime Inc.), Carlsbad, California
| | - Simon M Petersen-Jones
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lasing, Michigan
| | - Igor O Nasonkin
- Lineage Cell Therapeutics, Inc. (formerly BioTime Inc.), Carlsbad, California
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107
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Pei YC, Cheng YP, Chen JL, Lin CH, Wen CJ, Huang JJ. Early recovery of neuronal functioning in the sensory cortex after nerve reconstruction surgery. Restor Neurol Neurosci 2019; 37:409-419. [PMID: 31322584 PMCID: PMC6700653 DOI: 10.3233/rnn-190914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Nerve reconstructive surgery induces a transient loss and a prolonged and a gradual return of sensory inputs to the brain. It is unknown whether, following this massive peripheral denervation, the brain will experience a prolonged period of severe, intrinsic dysfunction. OBJECTIVE We aim to investigate the mechanisms of return of processing function in cortical neurons. METHODS We used the whisker model in rats to evaluate the functional recovery in the somatosensory cortex after a nerve reconstruction surgery. Multi-unit recording in the barrel cortex was performed in lightly anesthetized rats while their whiskers were stimulated by a whisker stimulator. RESULTS We observed a loss of neuronal responses to whisker stimulation 1 week after surgery, which started to recover 2 weeks after surgery. Following the surgery, only 11.8% of units had principle whiskers (PWs) returned to their original status while 17.7% had PWs different from their original status, indicating the effect of aberrant reinnervation on the whisker response map. CONCLUSIONS Robust neuronal responses to sensory stimulation even when only sparse sensory inputs are available in the early recovery phase. During this phase, aberrant reinnervation induces disorganized whisker tuning, a finding that might be account for the hypoesthesia and paresthesia during early recovery after nerve reconstruction.
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Affiliation(s)
- Yu-Chen Pei
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital at Linkou, Taoyuan City, Taiwan.,School of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan City, Taiwan.,Healthy Aging Research Center, Chang Gung University, Taoyuan City, Taiwan
| | - Yu-Po Cheng
- Department of Psychology, National Taiwan University, Taipei, Taiwan
| | - Ji-Lin Chen
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital at Linkou, Taoyuan City, Taiwan.,School of Medicine, Chang Gung University, Taoyuan City, Taiwan
| | - Cheng-Hung Lin
- School of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan City, Taiwan.,Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital at Linkou, Taoyuan City, Taiwan
| | - Chih-Jen Wen
- Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan City, Taiwan.,Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital at Linkou, Taoyuan City, Taiwan
| | - Jian-Jia Huang
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital at Linkou, Taoyuan City, Taiwan.,School of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Center for Vascularized Composite Allotransplantation, Chang Gung Memorial Hospital, Taoyuan City, Taiwan
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108
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Li G, Wang F, Yang W, Yang J, Wang Y, Wang W, Liu L. Development of an image biosensor based on an optogenetically engineered cell for visual prostheses. NANOSCALE 2019; 11:13213-13218. [PMID: 31184360 DOI: 10.1039/c9nr01688k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Visual prostheses provide blind patients with artificial vision via electrical stimulation of surviving visual cells resulting in partial restoration of vision in many patients. However, high-resolution visual perception, long-term biocompatibility and safety remain the significant challenges of existing visual prostheses. Here, we present a novel method to develop a new visual prosthesis using living cells as integrated electronics and implantable microelectrodes. The living cells modified with channelrhodopsin-2 showed excellent light-sensitive properties and encoded image information with cellular deformations triggered by light stimulation. The photoresponsive properties of the cells were determined using a single pixel imaging system, which indicated that the cells can act as a good light-sensitive biosensor. Additionally, the imaging feasibility of the cells was further validated through successful and clear imaging of several object scenes using the same system. This work represents a step toward the design and use of living cells as an image biosensor for the development of a new generation of high-resolution visual prostheses.
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Affiliation(s)
- Gongxin Li
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China. and Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110016, China and Key Laboratory of Advanced Process Control for Light Industry (Ministry of Education), Institute of Automation, Jiangnan University, Wuxi 214122, China
| | - Feifei Wang
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Wenguang Yang
- School of Electromechanical and Automotive Engineering, Yantai University, Yantai 264005, China
| | - Jia Yang
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China. and Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110016, China and University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuechao Wang
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China. and Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110016, China
| | - Wenxue Wang
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China. and Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110016, China
| | - Lianqing Liu
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China. and Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110016, China
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109
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Dorand RD, Benson BL, Huang LF, Petrosiute A, Huang AY. Insights From Dynamic Neuro-Immune Imaging on Murine Immune Responses to CNS Damage. Front Neurosci 2019; 13:737. [PMID: 31379488 PMCID: PMC6650615 DOI: 10.3389/fnins.2019.00737] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 07/02/2019] [Indexed: 01/22/2023] Open
Abstract
Evolving technologies and increasing understanding of human physiology over the past century have afforded our ability to intervene on human diseases using implantable bio-materials. These bio-electronic devices present a unique challenge through the creation of an interface between the native tissue and implantable bio-materials: the generation of host immune response surrounding such devices. While recent developments in cancer immunology seek to stimulate the immune system against cancer, successful long-term application of implantable bio-material devices need to durably minimize reactive immune processes at involved anatomical sites. Peripheral immune system response has been studied extensively for implanted bio-materials at various body sites. Examples include tooth composites (Gitalis et al., 2019), inguinal hernia repair (Heymann et al., 2019), and cardiac stents and pacemaker leads (Slee et al., 2016). Studies have also been extended to less well-studied immune reactivity in response to CNS neural-electronic implant devices. Recent technological advances in 2-Photon Laser Scanning Microscopy (2P-LSM) have allowed novel insights into in vivo immune response in a variety of tissue microenvironments. While imaging of peripheral tissues has provided an abundance of data with regards to immune cell dynamics, central nervous system (CNS) imaging is comparatively complicated by tissue accessibility and manipulation. Despite these challenges, the results of dynamic intravital neuro-immune imaging thus far have provided foundational insights into basic CNS biology. Utilizing a combination of intravital and ex vivo 2P-LSM, we have observed novel pathways allowing immune cells, stromal cells, cancer cells and proteins to communicate between the CNS parenchyma and peripheral vasculature. Similar to what has been reported in the intestinal tract, we have visualized myeloid cells extend dendritic processes across the blood brain barrier (BBB) into pial blood vessels. Furthermore, transient vessel leaks seen during systemic inflammation provide opportunities for cellular protein to be exchanged between the periphery and CNS. These insights provide new, visual information regarding immune surveillance and antigen presentation within the CNS. Furthermore, when combining intravital 2P-LSM and microfluidic devices complexed with mathematical modeling, we are gaining new insights into the intravascular behavior of circulating immune cells. This new knowledge into the basic mechanisms by which cells migrate to and interact with the CNS provide important considerations for the design of neuro-electronic biomaterials that have the potential to connect the peripheral-neural microenvironments into a unique, artificial interface.
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Affiliation(s)
- R Dixon Dorand
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Bryan L Benson
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Lauren F Huang
- Department of Pediatrics, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Agne Petrosiute
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States.,Department of Pediatrics, Case Western Reserve University School of Medicine, Cleveland, OH, United States.,Angie Fowler Adolescent & Young Adult (AYA) Cancer Institute/University Hospitals (UH) Rainbow Babies & Children's Hospital, Cleveland, OH, United States
| | - Alex Y Huang
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States.,Department of Pediatrics, Case Western Reserve University School of Medicine, Cleveland, OH, United States.,Angie Fowler Adolescent & Young Adult (AYA) Cancer Institute/University Hospitals (UH) Rainbow Babies & Children's Hospital, Cleveland, OH, United States
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110
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Meng M, Kiani M. Self-Image-Guided Ultrasonic Wireless Power Transmission to Millimeter-Sized Biomedical Implants. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2019; 2019:364-367. [PMID: 31945916 DOI: 10.1109/embc.2019.8857559] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This paper introduces the concept of self-image-guided ultrasonic (SIG-US) wireless power transmission (WPT) for robust and efficient WPT to millimeter-sized biomedical implants distributed inside the body. In SIG-US WPT, a sharp pulse is transmitted periodically by the implant to create short ringing with relatively various delays across an array of external (wearable) ultrasonic transducers. These relative delays are used to drive the external array as in phased-array beamforming, generating a highly focused ultrasound intensity at the implant's location due to the reciprocity. Therefore, regardless of implant's misalignment, orientation, and medium (i.e., without any prior knowledge) optimal parameters for beamforming is found by the SIG-US technique without the need for a conventional imaging system, suffering from high power consumption, size, cost, and complexity. In our proof-of-concept simulation setup with a linear transducer array (11 transducers), the SIG-US technique improved delivered power to a 1 mm3 implant with 6 mm misalignment (powering distance of 30 mm) by 95.7 times compared with conventional beamforming. In addition, for up to 6 mm implant's misalignment, the received power with the SIG-US technique only varied by 1.2 times compared with 156.3 times variation in the received power in conventional beamforming.
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111
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Shi Z, Zheng F, Zhou Z, Li M, Fan Z, Ye H, Zhang S, Xiao T, Chen L, Tao TH, Sun Y, Mao Y. Silk-Enabled Conformal Multifunctional Bioelectronics for Investigation of Spatiotemporal Epileptiform Activities and Multimodal Neural Encoding/Decoding. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1801617. [PMID: 31065516 PMCID: PMC6498121 DOI: 10.1002/advs.201801617] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 01/28/2019] [Indexed: 05/19/2023]
Abstract
Flexible electronics can serve as powerful tools for biomedical diagnosis and therapies of neurological disorders, particularly for application cases with brain-machine interfaces (BMIs). Existing conformal soft bioelectrodes are applicable for basic electrocorticogram (ECoG) collecting/monitoring. Nevertheless, as an emerging and promising approach, further multidisciplinary efforts are still demanded for in-depth exploitations with these conformal soft electronics toward their practical neurophysiological applications in both scientific research and real-world clinical operation. Here, clinically-friendly silk-supported/delivered soft bioelectronics are developed, and multiple functions and features valuable for customizable intracranial applications (e.g., biocompatible and spontaneously conformal coupling with cortical surface, spatiotemporal ECoG detecting/monitoring, electro-neurophysiological neural stimulating/decoding, controllable loading/delivery of therapeutic molecules, and parallel optical readouts of operating states) are integrated.
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Affiliation(s)
- Zhifeng Shi
- Department of NeurosurgeryHuashan Hospital of Fudan UniversityWulumuqi Zhong Road 12Shanghai200040China
| | - Faming Zheng
- State Key Laboratory of Transducer TechnologyShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China
| | - Zhitao Zhou
- State Key Laboratory of Transducer TechnologyShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China
| | - Meng Li
- The Rowland InstituteHarvard UniversityCambridgeMA02142USA
| | - Zhen Fan
- Department of NeurosurgeryHuashan Hospital of Fudan UniversityWulumuqi Zhong Road 12Shanghai200040China
| | - Huanpeng Ye
- State Key Laboratory of Mechanical System and VibrationShanghai Jiao Tong UniversityShanghai200240China
| | - Shan Zhang
- State Key Laboratory of Transducer TechnologyShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China
- School of Graduate StudyUniversity of Chinese Academy of SciencesBeijing100049China
| | - Ting Xiao
- State Key Laboratory of Transducer TechnologyShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China
- The Key Laboratory of Resource Chemistry of Ministry of EducationShanghai Normal UniversityShanghai200234China
| | - Liang Chen
- Department of NeurosurgeryHuashan Hospital of Fudan UniversityWulumuqi Zhong Road 12Shanghai200040China
| | - Tiger H. Tao
- State Key Laboratory of Transducer TechnologyShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China
- School of Graduate StudyUniversity of Chinese Academy of SciencesBeijing100049China
- Center of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of SciencesBeijing100049China
- School of Physical Science and TechnologyShanghai Tech UniversityShanghai200031China
| | - Yun‐Lu Sun
- State Key Laboratory of Integrated OptoelectronicsCollege of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun130012China
| | - Ying Mao
- Department of NeurosurgeryHuashan Hospital of Fudan UniversityWulumuqi Zhong Road 12Shanghai200040China
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112
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Enhanced spinal cord microstimulation using conducting polymer-coated carbon microfibers. Acta Biomater 2019; 90:71-86. [PMID: 30904548 DOI: 10.1016/j.actbio.2019.03.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 03/18/2019] [Accepted: 03/19/2019] [Indexed: 12/30/2022]
Abstract
Intraspinal microstimulation (ISMS) may help to restore motor functions after spinal cord injury. ISMS caudal to the lesion activates motoneurons and evokes selective movements with graded force in rats and other mammals. We investigated the safety and effectiveness of conducting polymer (CP)-coated carbon microfibers (CMFs) for ISMS. 7-µm-diameter CMFs coated with poly(3,4-ethylenedioxythiophene) doped with poly[(4-styrenesulfonic acid)-co-(maleic acid)] (PEDOT:PSS-co-MA) were used to apply current-controlled biphasic electric pulses at the cervical spinal cord (C7) of anesthetized rats. Electrode performance and motoneuron activation, as readout by voltage transients, cyclic voltammetry, electrochemical impedance spectroscopy, electromyography (EMG) and foreleg kinematics, were investigated as a function of microfiber length (50 µm vs. 250 µm) and presence of polymer coating. The microfibers were very effective in activating specific spinal motoneurons, with the lowest stimulus thresholds varying between -28 µA and -46 µA in the cathodic phase. EMG and kinematic thresholds decreased when the microfiber tip approached the targeted motor nucleus (triceps brachii, t.b.) from the dorsal spinal cord surface. ISMS with polymer-coated CMFs produced higher electrical activity in the t.b. fascicles compared to bare CMFs. PEDOT:PSS-co-MA coating of 250-µm CMFs avoided the generation of unsafe overvoltages for biphasic pulses up to -80/+40 µA in vivo, although the positive effect of the conducting polymer was lost after the application of a few thousands of electric pulses. Thus, CP-coated CMFs may provide an effective and minimally invasive electrode for ISMS; however, polymer optimization is still required to improve its electrical stability and safety for long-term use. Statement of significance Intraspinal microstimulation may restore motor functions after spinal cord injury. In the present study we demonstrate that carbon microfibers (CMFs) coated with the conducting polymer PEDOT:PSS-co-MA can be advantageously used for this purpose. These microfibers allow for both effective and temporarily safe electrical activation of spinal motor circuits with high spatial resolution. The presence of the polymer enhances the effectiveness of the electrical stimuli to recruit spinal motoneurons. Thus, conducting polymer-coated CMFs have potential for the development of advanced neuroprosthetic devices, although further improvements are needed regarding their electrochemical and mechanical stability.
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113
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Nambiar A, Nolta NF, Han M. 3D Reconstruction of the Intracortical Volume Around a Hybrid Microelectrode Array. Front Neurosci 2019; 13:393. [PMID: 31068786 PMCID: PMC6491727 DOI: 10.3389/fnins.2019.00393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/05/2019] [Indexed: 11/17/2022] Open
Abstract
Extensive research using penetrating electrodes implanted in the central and peripheral nervous systems has been performed for many decades with significant advances made in recent years. While penetrating devices provide proximity to individual neurons in vivo, they suffer from declining performance over the course of months and often fail within a year. 2D histology studies using serial tissue sections have been extremely insightful in identifying and quantifying factors such as astroglial scar formation and neuronal death around the implant sites that may be contributing to failures. However, 2D histology has limitations in providing a holistic picture of the problems occurring at the electrode-tissue interface and struggles to analyze tissue below the electrode tips where the electrode tracks are no longer visible. In this study, we present 3D reconstruction of serial sections to overcome the limitations of 2D histological analysis. We used a cohort of software: XuvStitch, AutoAligner, and Imaris coupled with custom MATLAB programming to correct warping effects. Once the 3D image volume was reconstructed, we were able to use Imaris to quantify neuronal densities around the electrode tips of a hybrid microelectrode array incorporating Blackrock, Microprobes, and NeuroNexus electrodes in the same implant. This paper presents proof-of-concept and detailed methodological description of a technique which can be used to quantify neuronal densities in future studies of implanted electrodes.
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Affiliation(s)
- Aparna Nambiar
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, United States
| | - Nicholas F Nolta
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, United States
| | - Martin Han
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, United States
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114
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Adewole DO, Serruya MD, Wolf JA, Cullen DK. Bioactive Neuroelectronic Interfaces. Front Neurosci 2019; 13:269. [PMID: 30983957 PMCID: PMC6449725 DOI: 10.3389/fnins.2019.00269] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/07/2019] [Indexed: 12/31/2022] Open
Abstract
Within the neural engineering field, next-generation implantable neuroelectronic interfaces are being developed using biologically-inspired and/or biologically-derived materials to improve upon the stability and functional lifetime of current interfaces. These technologies use biomaterials, bioactive molecules, living cells, or some combination of these, to promote host neuronal survival, reduce the foreign body response, and improve chronic device-tissue integration. This article provides a general overview of the different strategies, milestones, and evolution of bioactive neural interfaces including electrode material properties, biological coatings, and "decoration" with living cells. Another such biohybrid approach developed in our lab uses preformed implantable micro-tissue featuring long-projecting axonal tracts encased within carrier biomaterial micro-columns. These so-called "living electrodes" have been engineered with carefully tailored material, mechanical, and biological properties to enable natural, synaptic based modulation of specific host circuitry while ultimately being under computer control. This article provides an overview of these living electrodes, including design and fabrication, performance attributes, as well as findings to date characterizing in vitro and in vivo functionality.
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Affiliation(s)
- Dayo O. Adewole
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Mijail D. Serruya
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States
| | - John A. Wolf
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - D. Kacy Cullen
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
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115
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Cassar IR, Yu C, Sambangi J, Lee CD, Whalen JJ, Petrossians A, Grill WM. Electrodeposited platinum-iridium coating improves in vivo recording performance of chronically implanted microelectrode arrays. Biomaterials 2019; 205:120-132. [PMID: 30925400 DOI: 10.1016/j.biomaterials.2019.03.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 03/13/2019] [Accepted: 03/13/2019] [Indexed: 02/08/2023]
Abstract
Reliable single unit neuron recordings from chronically implanted microelectrode arrays (MEAs) are essential tools in the field of neural engineering. However, following implantation, MEAs undergo a foreign body response that functionally isolates them from the brain and reduces the useful longevity of the array. We tested a novel electrodeposited platinum-iridium coating (EPIC) on penetrating recording MEAs to determine if it improved recording performance. We chronically implanted the arrays in rats and used electrophysiological and histological measurements to compare quantitatively the single unit recording performance of coated vs. uncoated electrodes over a 12-week period. The coated electrodes had substantially lower impedance at 1 kHz and reduced noise, increased signal-to-noise ratio, and increased number of discernible units per electrode as compared to uncoated electrodes. Post-mortem immunohistochemistry showed no significant differences in the immune response between coated and uncoated electrodes. Overall, the EPIC arrays provided superior recording performance than uncoated arrays, likely due to lower electrode impedance and reduced noise.
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Affiliation(s)
- Isaac R Cassar
- Department of Biomedical Engineering, School of Engineering, Duke University, NC, USA
| | - Chunxiu Yu
- Department of Biomedical Engineering, School of Engineering, Duke University, NC, USA; Department of Biological Science, Michigan Technological University, MI, USA
| | - Jaydeep Sambangi
- Department of Biomedical Engineering, School of Engineering, Duke University, NC, USA
| | | | | | | | - Warren M Grill
- Department of Biomedical Engineering, School of Engineering, Duke University, NC, USA; Department of Neurobiology, School of Medicine, NC, USA; Department of Neurosurgery, School of Medicine, NC, USA; Department of Electrical and Computer Engineering, School of Engineering, Duke University, NC, USA.
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116
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Lu L, Fu X, Liew Y, Zhang Y, Zhao S, Xu Z, Zhao J, Li D, Li Q, Stanley GB, Duan X. Soft and MRI Compatible Neural Electrodes from Carbon Nanotube Fibers. NANO LETTERS 2019; 19:1577-1586. [PMID: 30798604 DOI: 10.1021/acs.nanolett.8b04456] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Soft and magnetic resonance imaging (MRI) compatible neural electrodes enable stable chronic electrophysiological measurements and anatomical or functional MRI studies of the entire brain without electrode interference with MRI images. These properties are important for many studies, ranging from a fundamental neurophysiological study of functional MRI signals to a chronic neuromodulatory effect investigation of therapeutic deep brain stimulation. Here we develop soft and MRI compatible neural electrodes using carbon nanotube (CNT) fibers with a diameter from 20 μm down to 5 μm. The CNT fiber electrodes demonstrate excellent interfacial electrochemical properties and greatly reduced MRI artifacts than PtIr electrodes under a 7.0 T MRI scanner. With a shuttle-assisted implantation strategy, we show that the soft CNT fiber electrodes can precisely target specific brain regions and record high-quality single-unit neural signals. Significantly, they are capable of continuously detecting and isolating single neuronal units from rats for up to 4-5 months without electrode repositioning, with greatly reduced brain inflammatory responses as compared to their stiff metal counterparts. In addition, we show that due to their high tensile strength, the CNT fiber electrodes can be retracted controllably postinsertion, which provides an effective and convenient way to do multidepth recording or potentially selecting cells with particular response properties. The chronic recording stability and MRI compatibility, together with their small size, provide the CNT fiber electrodes unique research capabilities for both basic and applied neuroscience studies.
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Affiliation(s)
- Linlin Lu
- Department of Biomedical Engineering, College of Engineering , Peking University , Beijing 100871 , China
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Atlanta , Georgia 30332 , United States
| | - Xuefeng Fu
- Department of Biomedical Engineering, College of Engineering , Peking University , Beijing 100871 , China
| | - Yijuin Liew
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Atlanta , Georgia 30332 , United States
| | - Yongyi Zhang
- Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences , Suzhou 215123 , China
| | - Siyuan Zhao
- Department of Biomedical Engineering, College of Engineering , Peking University , Beijing 100871 , China
- Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100871 , China
| | - Zheng Xu
- Department of Biomedical Engineering, College of Engineering , Peking University , Beijing 100871 , China
| | - Jingna Zhao
- Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences , Suzhou 215123 , China
| | - Da Li
- Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences , Suzhou 215123 , China
| | - Qingwen Li
- Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences , Suzhou 215123 , China
| | - Garrett B Stanley
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Atlanta , Georgia 30332 , United States
| | - Xiaojie Duan
- Department of Biomedical Engineering, College of Engineering , Peking University , Beijing 100871 , China
- Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100871 , China
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117
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Guan S, Wang J, Gu X, Zhao Y, Hou R, Fan H, Zou L, Gao L, Du M, Li C, Fang Y. Elastocapillary self-assembled neurotassels for stable neural activity recordings. SCIENCE ADVANCES 2019; 5:eaav2842. [PMID: 30944856 PMCID: PMC6436924 DOI: 10.1126/sciadv.aav2842] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 02/06/2019] [Indexed: 05/18/2023]
Abstract
Implantable neural probes that are mechanically compliant with brain tissue offer important opportunities for stable neural interfaces in both basic neuroscience and clinical applications. Here, we developed a Neurotassel consisting of an array of flexible and high-aspect ratio microelectrode filaments. A Neurotassel can spontaneously assemble into a thin and implantable fiber through elastocapillary interactions when withdrawn from a molten, tissue-dissolvable polymer. Chronically implanted Neurotassels elicited minimal neuronal cell loss in the brain and enabled stable activity recordings of the same population of neurons in mice learning to perform a task. Moreover, Neurotassels can be readily scaled up to 1024 microelectrode filaments, each with a neurite-scale cross-sectional footprint of 3 × 1.5 μm2, to form implantable fibers with a total diameter of ~100 μm. With their ultrasmall sizes, high flexibility, and scalability, Neurotassels offer a new approach for stable neural activity recording and neuroprosthetics.
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Affiliation(s)
- S. Guan
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - J. Wang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - X. Gu
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Y. Zhao
- College of Mechanical and Vehicle Engineering, Hunan University, Changsha 410082, China
| | - R. Hou
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - H. Fan
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - L. Zou
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - L. Gao
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - M. Du
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - C. Li
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- Corresponding author. (C.L.); (Y.F.)
| | - Y. Fang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- Corresponding author. (C.L.); (Y.F.)
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Kil D, Bovet Carmona M, Ceyssens F, Deprez M, Brancato L, Nuttin B, Balschun D, Puers R. Dextran as a Resorbable Coating Material for Flexible Neural Probes. MICROMACHINES 2019; 10:mi10010061. [PMID: 30658409 PMCID: PMC6356287 DOI: 10.3390/mi10010061] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/27/2018] [Accepted: 01/15/2019] [Indexed: 12/13/2022]
Abstract
In the quest for chronically reliable and bio-tolerable brain interfaces there has been a steady evolution towards the use of highly flexible, polymer-based electrode arrays. The reduced mechanical mismatch between implant and brain tissue has shown to reduce the evoked immune response, which in turn has a positive effect on signal stability and noise. Unfortunately, the low stiffness of the implants also has practical repercussions, making surgical insertion extremely difficult. In this work we explore the use of dextran as a coating material that temporarily stiffens the implant, preventing buckling during insertion. The mechanical properties of dextran coated neural probes are characterized, as well as the different parameters which influence the dissolution rate. Tuning parameters, such as coating thickness and molecular weight of the used dextran, allows customization of the stiffness and dissolution time to precisely match the user's needs. Finally, the immunological response to the coated electrodes was analyzed by performing a histological examination after four months of in vivo testing. The results indicated that a very limited amount of glial scar tissue was formed. Neurons have also infiltrated the area that was initially occupied by the dissolving dextran coating. There was no noticeable drop in neuron density around the site of implantation, confirming the suitability of the coating as a temporary aid during implantation of highly flexible polymer-based neural probes.
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Affiliation(s)
- Dries Kil
- ESAT-MICAS, KU Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium.
| | - Marta Bovet Carmona
- Laboratory for Biological Psychology, Brain & Cognition, KU Leuven, Tiensestraat 102, 3000 Leuven, Belgium.
| | - Frederik Ceyssens
- ESAT-MICAS, KU Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium.
| | - Marjolijn Deprez
- Experimental Neurosurgery and Neuroanatomy, UZ Herestraat 49 box 7003, 3000 Leuven, Belgium.
| | - Luigi Brancato
- ESAT-MICAS, KU Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium.
| | - Bart Nuttin
- Experimental Neurosurgery and Neuroanatomy, UZ Herestraat 49 box 7003, 3000 Leuven, Belgium.
| | - Detlef Balschun
- Laboratory for Biological Psychology, Brain & Cognition, KU Leuven, Tiensestraat 102, 3000 Leuven, Belgium.
| | - Robert Puers
- ESAT-MICAS, KU Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium.
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119
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Butnaru D, Chapman J. The impact of self-replicating proteins on inflammation, autoimmunity and neurodegeneration-An untraveled path. Autoimmun Rev 2019; 18:231-240. [PMID: 30639644 DOI: 10.1016/j.autrev.2018.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/12/2018] [Indexed: 02/08/2023]
Abstract
The central nervous system (CNS) in neurodegenerative diseases is a battlefield in which microglia fight a highly atypical battle. During the inflammatory process microglia themselves become dysfunctional and even with all the available immune arsenal including cytokine or/and antibody production, the battle is eventually lost. A closer look into the picture will reveal the fact that this is mainly due to the atypical characteristics of the infectious agent. The supramolecular assemblies of misfolded proteins carry unique features not encountered in any of the common pathogens. Through misfolding, proteins undergo conformational changes which make them become immunogenic, neurotoxic and highly infective. The immunogenicity appears to be triggered by the exposure of previously hidden hydrophobic portions in proteins which act as damage-associated molecular patters (DAMPs) for the immune system. The neurotoxicity and infectivity are promoted by the small oligomeric forms of misfolded proteins/peptides. Oligomers adopt conformations such as tubular-like, beta-barrel-like, etc., that penetrate cell membranes through their hydrophobic surfaces, thus destabilizing ionic homeostasis. At the same time, oligomers act as a seed for protein misfolding through a prion/prion-like mechanism. Here, we propose the hypothesis that oligomers have catalytic surfaces and exercise their capacity to infect native proteins through specific characteristics such as hydrophobic, electrostatic and π-π stacking interactions as well as the specific surface area (SSA), surface curvature and surface chemistry of their nanoscale supramolecular assemblies. All these are the key elements for prion/prion-like mechanism of self-replication and disease spreading within the CNS. Thus, understanding the mechanism of prion's templating activity may help us in the prevention and development of novel therapeutic strategies for neurodegenerative diseases.
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Affiliation(s)
- Dana Butnaru
- The Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel Hashomer, Israel.
| | - Joab Chapman
- Sheba Medical Center, Israel; Robert and Martha Harden Chair in Mental and Neurological Diseases, Sackler Faculty of Medicine, Tel Aviv University, Israel
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120
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Krukiewicz K, Chudy M, Gregg S, Biggs MJP. The Synergistic Effects of Gold Particles and Dexamethasone on the Electrochemical and Biological Performance of PEDOT Neural Interfaces. Polymers (Basel) 2019; 11:E67. [PMID: 30960051 PMCID: PMC6402010 DOI: 10.3390/polym11010067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 12/15/2018] [Accepted: 12/29/2018] [Indexed: 12/12/2022] Open
Abstract
Although neural devices have shown efficacy in the treatment of neurodegenerative diseases, their functionality is limited by the inflammatory state and glial scar formation associated with chronic implantation. The aim of this study was to investigate neural electrode performance following functionalization with an anti-inflammatory coating derived from a conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) matrix doped with dexamethasone (Dex) and decorated with Au particles. Pristine PEDOT, PEDOT-Dex and their gold-decorated analogues (PEDOT/Au and PEDOT-Dex/Au) were formulated by electrochemical deposition and characterized with respect to electrode electrochemical properties, surface morphology and biocompatibility towards primary neural cells. Through a process of gold deposition, it was possible to eliminate the initial burst release observed in PEDOT-Dex and maintain a stable, stepwise increase in Dex elution over 7 days. The released amounts of Dex exceeded the concentrations considered as therapeutic for both PEDOT-Dex and PEDOT-Dex/Au. The results clearly indicated that the presence of either Dex or Au particles facilitated the outgrowth of neurites. Finally, it was shown that the application of composite materials, such as PEDOT-Dex/Au, is an efficient way to improve the efficacy of neural interfaces in vitro.
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Affiliation(s)
- Katarzyna Krukiewicz
- Centre for Research in Medical Devices, National University of Ireland Galway, Newcastle Road, H91 W2TY Galway, Ireland.
- Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, M. Strzody 9, 44-100 Gliwice, Poland.
| | - Magdalena Chudy
- Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, M. Strzody 9, 44-100 Gliwice, Poland.
| | - Stephen Gregg
- Centre for Research in Medical Devices, National University of Ireland Galway, Newcastle Road, H91 W2TY Galway, Ireland.
| | - Manus J P Biggs
- Centre for Research in Medical Devices, National University of Ireland Galway, Newcastle Road, H91 W2TY Galway, Ireland.
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121
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Bennett C, Mohammed F, Álvarez-Ciara A, Nguyen MA, Dietrich WD, Rajguru SM, Streit WJ, Prasad A. Neuroinflammation, oxidative stress, and blood-brain barrier (BBB) disruption in acute Utah electrode array implants and the effect of deferoxamine as an iron chelator on acute foreign body response. Biomaterials 2019; 188:144-159. [PMID: 30343257 PMCID: PMC6300159 DOI: 10.1016/j.biomaterials.2018.09.040] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/20/2018] [Accepted: 09/24/2018] [Indexed: 02/06/2023]
Abstract
The use of intracortical microelectrode arrays has gained significant attention in being able to help restore function in paralysis patients and study the brain in various neurological disorders. Electrode implantation in the cortex causes vasculature or blood-brain barrier (BBB) disruption and thus elicits a foreign body response (FBR) that results in chronic inflammation and may lead to poor electrode performance. In this study, a comprehensive insight into the acute molecular mechanisms occurring at the Utah electrode array-tissue interface is provided to understand the oxidative stress, neuroinflammation, and neurovascular unit (astrocytes, pericytes, and endothelial cells) disruption that occurs following microelectrode implantation. Quantitative real time polymerase chain reaction (qRT-PCR) was used to quantify the gene expression at acute time-points of 48-hr, 72-hr, and 7-days for factors mediating oxidative stress, inflammation, and BBB disruption in rats implanted with a non-functional 4 × 4 Utah array in the somatosensory cortex. During vascular disruption, free iron released into the brain parenchyma can exacerbate the FBR, leading to oxidative stress and thus further contributing to BBB degradation. To reduce the free iron released into the brain tissue, the effects of an iron chelator, deferoxamine mesylate (DFX), was also evaluated.
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Affiliation(s)
- Cassie Bennett
- Department of Biomedical Engineering, University of Miami, FL, USA
| | - Farrah Mohammed
- Department of Biomedical Engineering, University of Miami, FL, USA
| | | | | | | | - Suhrud M Rajguru
- Department of Biomedical Engineering, University of Miami, FL, USA
| | | | - Abhishek Prasad
- Department of Biomedical Engineering, University of Miami, FL, USA.
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122
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Goding J, Vallejo-Giraldo C, Syed O, Green R. Considerations for hydrogel applications to neural bioelectronics. J Mater Chem B 2019; 7:1625-1636. [DOI: 10.1039/c8tb02763c] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hydrogels have garnered interest as materials in bioelectronics due to the capacity to tailor their properties. Appropriate selection and design of hydrogel systems for this application requires an understanding of the physical, chemical and biological properties as well as their structure–property relationships.
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Affiliation(s)
- Josef Goding
- Department of Bioengineering
- Imperial College London
- London SW72AS
- UK
| | | | - Omaer Syed
- Department of Bioengineering
- Imperial College London
- London SW72AS
- UK
| | - Rylie Green
- Department of Bioengineering
- Imperial College London
- London SW72AS
- UK
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123
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Eles JR, Vazquez AL, Kozai TDY, Cui XT. Meningeal inflammatory response and fibrous tissue remodeling around intracortical implants: An in vivo two-photon imaging study. Biomaterials 2018; 195:111-123. [PMID: 30634095 DOI: 10.1016/j.biomaterials.2018.12.031] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/15/2018] [Accepted: 12/28/2018] [Indexed: 12/21/2022]
Abstract
Meningeal inflammation and encapsulation of neural electrode arrays is a leading cause of device failure, yet little is known about how it develops over time or what triggers it. This work characterizes the dynamic changes of meningeal inflammatory cells and collagen-I in order to understand the meningeal tissue response to neural electrode implantation. We use in vivo two-photon microscopy of CX3CR1-GFP mice over the first month after electrode implantation to quantify changes in inflammatory cell behavior as well as meningeal collagen-I remodeling. We define a migratory window during the first day after electrode implantation hallmarked by robust inflammatory cell migration along electrodes in the meninges as well as cell trafficking through meningeal venules. This migratory window attenuates by 2 days post-implant, but over the next month, the meningeal collagen-I remodels to conform to the surface of the electrode and thickens. This work shows that there are distinct time courses for initial meningeal inflammatory cell infiltration and meningeal collagen-I remodeling. This may indicate a therapeutic window early after implantation for modulation and mitigation of meningeal inflammation.
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Affiliation(s)
- J R Eles
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States
| | - A L Vazquez
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States; Radiology, University of Pittsburgh, United States
| | - T D Y Kozai
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, United States; NeuroTech Center of the University of Pittsburgh Brain Institute, United States; Center for Neuroscience, University of Pittsburgh, United States
| | - X T Cui
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, United States.
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124
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Perkins LN, Semu D, Shen J, Boas DA, Gardner TJ. High-density microfibers as a potential optical interface to reach deep brain regions. J Neural Eng 2018; 15:066002. [PMID: 30127101 PMCID: PMC6239906 DOI: 10.1088/1741-2552/aadbb2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Optical techniques for recording and manipulating neural activity have traditionally been constrained to superficial brain regions due to light scattering. New techniques are needed to extend optical access to large 3D volumes in deep brain areas, while retaining local connectivity. APPROACH We have developed a method to implant bundles of hundreds or thousands of optical microfibers, each with a diameter of 8 μm. During insertion, each fiber moves independently, following a path of least resistance. The fibers achieve near total internal reflection, enabling optically interfacing with the tissue near each fiber aperture. MAIN RESULTS At a depth of 3 mm, histology shows fibers consistently splay over 1 mm in diameter throughout the target region. Immunohistochemical staining after chronic implants reveals neurons in close proximity to the fiber tips. Models of photon fluence indicate that fibers can be used as a stimulation light source to precisely activate distinct patterns of neurons by illuminating a subset of fibers in the bundle. By recording fluorescent beads diffusing in water, we demonstrate the recording capability of the fibers. SIGNIFICANCE Our histology, modeling and fluorescent bead recordings suggest that the optical microfibers may provide a minimally invasive, stable, bidirectional interface for recording or stimulating genetic probes in deep brain regions-a hyper-localized form of fiber photometry.
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Affiliation(s)
- L Nathan Perkins
- Graduate Program in Neuroscience, Boston University, Boston, MA 02215, United States of America
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125
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Woods V, Trumpis M, Bent B, Palopoli-Trojani K, Chiang CH, Wang C, Yu C, Insanally MN, Froemke RC, Viventi J. Long-term recording reliability of liquid crystal polymer µECoG arrays. J Neural Eng 2018; 15:066024. [PMID: 30246690 PMCID: PMC6342453 DOI: 10.1088/1741-2552/aae39d] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE The clinical use of microsignals recorded over broad cortical regions is largely limited by the chronic reliability of the implanted interfaces. APPROACH We evaluated the chronic reliability of novel 61-channel micro-electrocorticographic (µECoG) arrays in rats chronically implanted for over one year and using accelerated aging. Devices were encapsulated with polyimide (PI) or liquid crystal polymer (LCP), and fabricated using commercial manufacturing processes. In vitro failure modes and predicted lifetimes were determined from accelerated soak testing. Successful designs were implanted epidurally over the rodent auditory cortex. Trends in baseline signal level, evoked responses and decoding performance were reported for over one year of implantation. MAIN RESULTS Devices fabricated with LCP consistently had longer in vitro lifetimes than PI encapsulation. Our accelerated aging results predicted device integrity beyond 3.4 years. Five implanted arrays showed stable performance over the entire implantation period (247-435 d). Our regression analysis showed that impedance predicted signal quality and information content only in the first 31 d of recordings and had little predictive value in the chronic phase (>31 d). In the chronic phase, site impedances slightly decreased yet decoding performance became statistically uncorrelated with impedance. We also employed an improved statistical model of spatial variation to measure sensitivity to locally varying fields, which is typically concealed in standard signal power calculations. SIGNIFICANCE These findings show that µECoG arrays can reliably perform in chronic applications in vivo for over one year, which facilitates the development of a high-density, clinically viable interface.
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Affiliation(s)
- Virginia Woods
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
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126
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Straka MM, Shafer B, Vasudevan S, Welle C, Rieth L. Characterizing Longitudinal Changes in the Impedance Spectra of In-Vivo Peripheral Nerve Electrodes. MICROMACHINES 2018; 9:mi9110587. [PMID: 30424513 PMCID: PMC6266965 DOI: 10.3390/mi9110587] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 11/02/2018] [Accepted: 11/05/2018] [Indexed: 12/18/2022]
Abstract
Characterizing the aging processes of electrodes in vivo is essential in order to elucidate the changes of the electrode–tissue interface and the device. However, commonly used impedance measurements at 1 kHz are insufficient for determining electrode viability, with measurements being prone to false positives. We implanted cohorts of five iridium oxide (IrOx) and six platinum (Pt) Utah arrays into the sciatic nerve of rats, and collected the electrochemical impedance spectroscopy (EIS) up to 12 weeks or until array failure. We developed a method to classify the shapes of the magnitude and phase spectra, and correlated the classifications to circuit models and electrochemical processes at the interface likely responsible. We found categories of EIS characteristic of iridium oxide tip metallization, platinum tip metallization, tip metal degradation, encapsulation degradation, and wire breakage in the lead. We also fitted the impedance spectra as features to a fine-Gaussian support vector machine (SVM) algorithm for both IrOx and Pt tipped arrays, with a prediction accuracy for categories of 95% and 99%, respectively. Together, this suggests that these simple and computationally efficient algorithms are sufficient to explain the majority of variance across a wide range of EIS data describing Utah arrays. These categories were assessed over time, providing insights into the degradation and failure mechanisms for both the electrode–tissue interface and wire bundle. Methods developed in this study will allow for a better understanding of how EIS can characterize the physical changes to electrodes in vivo.
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Affiliation(s)
- Malgorzata M Straka
- Center for Bioelectronic Medicine, Feinstein Institute for Medical Research, Northwell Health, Manhasset, NY 11030, USA.
| | - Benjamin Shafer
- U.S. Food and Drug Administration, Center for Devices and Radiological Health (CDRH), Office of Science and Engineering Laboratory (OSEL), Division of Biomedical Physics (DBP), Silver Spring, MD 20993, USA.
| | - Srikanth Vasudevan
- U.S. Food and Drug Administration, Center for Devices and Radiological Health (CDRH), Office of Science and Engineering Laboratory (OSEL), Division of Biomedical Physics (DBP), Silver Spring, MD 20993, USA.
| | - Cristin Welle
- Departments of Neurosurgery and Bioengineering, University of Colorado, Aurora, CO 80045, USA.
| | - Loren Rieth
- Center for Bioelectronic Medicine, Feinstein Institute for Medical Research, Northwell Health, Manhasset, NY 11030, USA.
- Departments of Electrical Engineering and Bioengineering, University of Utah, Salt Lake City, UT 84112, USA.
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127
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Wellman SM, Cambi F, Kozai TD. The role of oligodendrocytes and their progenitors on neural interface technology: A novel perspective on tissue regeneration and repair. Biomaterials 2018; 183:200-217. [PMID: 30172245 PMCID: PMC6469877 DOI: 10.1016/j.biomaterials.2018.08.046] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 08/08/2018] [Accepted: 08/20/2018] [Indexed: 12/11/2022]
Abstract
Oligodendrocytes and their precursors are critical glial facilitators of neurophysiology, which is responsible for cognition and behavior. Devices that are used to interface with the brain allow for a more in-depth analysis of how neurons and these glia synergistically modulate brain activity. As projected by the BRAIN Initiative, technologies that acquire a high resolution and robust sampling of neural signals can provide a greater insight in both the healthy and diseased brain and support novel discoveries previously unobtainable with the current state of the art. However, a complex series of inflammatory events triggered during device insertion impede the potential applications of implanted biosensors. Characterizing the biological mechanisms responsible for the degradation of intracortical device performance will guide novel biomaterial and tissue regenerative approaches to rehabilitate the brain following injury. Glial subtypes which assist with neuronal survival and exchange of electrical signals, mainly oligodendrocytes, their precursors, and the insulating myelin membranes they produce, are sensitive to inflammation commonly induced from insults to the brain. This review explores essential physiological roles facilitated by oligodendroglia and their precursors and provides insight into their pathology following neurodegenerative injury and disease. From this knowledge, inferences can be made about the impact of device implantation on these supportive glia in order to engineer effective strategies that can attenuate their responses, enhance the efficacy of neural interfacing technology, and provide a greater understanding of the challenges that impede wound healing and tissue regeneration during pathology.
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Affiliation(s)
- Steven M Wellman
- Department of Bioengineering, University of Pittsburgh, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | - Franca Cambi
- Veterans Administration Pittsburgh, Pittsburgh, PA, USA; Department of Neurology, University of Pittsburgh, USA
| | - Takashi Dy Kozai
- Department of Bioengineering, University of Pittsburgh, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA, USA; Center for Neuroscience, University of Pittsburgh, USA; McGowan Institute of Regenerative Medicine, University of Pittsburgh, USA; NeuroTech Center, University of Pittsburgh Brain Institute, USA.
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128
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Anjum SMM, Käufer C, Hopfengärtner R, Waltl I, Bröer S, Löscher W. Automated quantification of EEG spikes and spike clusters as a new read out in Theiler's virus mouse model of encephalitis-induced epilepsy. Epilepsy Behav 2018; 88:189-204. [PMID: 30292054 DOI: 10.1016/j.yebeh.2018.09.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/13/2018] [Accepted: 09/16/2018] [Indexed: 12/17/2022]
Abstract
Intracerebral infection of C57BL/6 mice with Theiler's murine encephalomyelitis virus (TMEV) replicates many features of viral encephalitis-induced epilepsy in humans, including neuroinflammation, early (insult-associated) and late (spontaneous) seizures, neurodegeneration in the hippocampus, and cognitive and behavioral alterations. Thus, this model may be ideally suited to study mechanisms involved in encephalitis-induced epilepsy as potential targets for epilepsy prevention. However, spontaneous recurrent seizures (SRS) occur too infrequently to be useful as a biomarker of epilepsy, e.g., for drug studies. This prompted us to evaluate whether epileptiform spikes or spike clusters in the cortical electroencephalogram (EEG) may be a useful surrogate of epilepsy in this model. For this purpose, we developed an algorithm that allows efficient and large-scale EEG analysis of early and late seizures, spikes, and spike clusters in the EEG. While 77% of the infected mice exhibited early seizures, late seizures were only observed in 33% of the animals. The clinical characteristics of early and late seizures did not differ except that late generalized convulsive (stage 5) seizures were significantly longer than early stage 5 seizures. Furthermore, the frequency of SRS was much lower than the frequency of early seizures. Continuous (24/7) video-EEG monitoring over several months following infection indicated that the latent period to onset of SRS was 61 (range 16-91) days. Spike and spike clusters were significantly more frequent in infected mice with late seizures than in infected mice without seizures or in mock-infected sham controls. Based on the results of this study, increases in EEG spikes and spike clusters in groups of infected mice may be used as a new readout for studies on antiepileptogenic or disease-modifying drug effects in this model, because the significant increase in average spike counts in mice with late seizures obviously indicates a proepileptogenic alteration.
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Affiliation(s)
- Syed Muhammad Muneeb Anjum
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | | | - Inken Waltl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
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129
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Moore J, Castellanos S, Xu S, Wood B, Ren H, Tse ZTH. Applications of Wireless Power Transfer in Medicine: State-of-the-Art Reviews. Ann Biomed Eng 2018; 47:22-38. [PMID: 30306381 DOI: 10.1007/s10439-018-02142-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 09/24/2018] [Indexed: 12/17/2022]
Abstract
Magnetic resonance within the field of wireless power transfer has seen an increase in popularity over the past decades. This rise can be attributed to the technological advances of electronics and the increased efficiency of popular battery technologies. The same principles of electromagnetic theory can be applied to the medical field. Several medical devices intended for use inside the body use batteries and electrical circuits that could be powered wirelessly. Other medical devices limit the mobility or make patients uncomfortable while in use. The fundamental theory of electromagnetics can improve the field by solving some of these problems. This survey paper summarizes the recent uses and discoveries of wireless power in the medical field. A comprehensive search for papers was conducted using engineering search engines and included papers from related conferences. During the initial search, 247 papers were found then non-relevant papers were eliminated to leave only suitable material. Seventeen relevant journal papers and/or conference papers were found, then separated into defined categories: Implants, Pumps, Ultrasound Imaging, and Gastrointestinal (GI) Endoscopy. The approach and methods for each paper were analyzed and compared yielding a comprehensive review of these state of the art technologies.
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Affiliation(s)
- Julian Moore
- School of Electrical and Computer Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Sharon Castellanos
- School of Electrical and Computer Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Sheng Xu
- Center for Interventional Oncology, Radiology and Imaging Sciences, NIH Clinical Center, National Institute of Biomedical Imaging and Bioengineering & National Cancer Institute Center for Cancer Research, National Institutes of Health, Bethesda, MD, USA
| | - Bradford Wood
- Center for Interventional Oncology, Radiology and Imaging Sciences, NIH Clinical Center, National Institute of Biomedical Imaging and Bioengineering & National Cancer Institute Center for Cancer Research, National Institutes of Health, Bethesda, MD, USA
| | - Hongliang Ren
- Department of Biomedical Engineering, National University of Singapore, Singapore, 119077, Singapore
| | - Zion Tsz Ho Tse
- School of Electrical and Computer Engineering, The University of Georgia, Athens, GA, 30602, USA.
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130
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Golabchi A, Wu B, Li X, Carlisle DL, Kozai TDY, Friedlander RM, Cui XT. Melatonin improves quality and longevity of chronic neural recording. Biomaterials 2018; 180:225-239. [PMID: 30053658 PMCID: PMC6179369 DOI: 10.1016/j.biomaterials.2018.07.026] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 07/06/2018] [Accepted: 07/13/2018] [Indexed: 12/17/2022]
Abstract
The chronic performance of implantable neural electrodes is hindered by inflammatory brain tissue responses, including microglia activation, glial scarring, and neuronal loss. Melatonin (MT) has shown remarkable neuroprotective and neurorestorative effects in treating central nervous system (CNS) injuries and degeneration by inhibiting caspase-1, -3, and -9 activation and mitochondrial cytochrome c release, as well as reducing oxidative stress and neuroinflammation. This study examined the effect of MT administration on the quality and longevity of neural recording from an implanted microelectrode in the visual cortex of mice for 16 weeks. MT (30 mg/kg) was administered via daily intraperitoneal injection for acute (3 days before and 14 days post-implantation) and chronic (3 days before and 16 weeks post-implantation) exposures. During the first 4 weeks, both MT groups showed significantly higher single-unit (SU) yield, signal-to-noise ratio (SNR), and amplitude compared to the vehicle control group. However, after 4 weeks of implantation, the SU yield of the acute treatment group dropped to the same level as the control group, while the chronic treatment group maintained significantly higher SU yield compared to both acute (week 5-16) and control (week 0-16) mice. Histological studies revealed a significant increase in neuronal viability and decrease in neuronal apoptosis around the implanted electrode at week 16 in the chronic group in comparison to control and acute subjects, which is correlated with reduced oxidative stress and increased number of pro-regeneration arginase-1 positive microglia cells. These results demonstrate the potent effect of MT treatment in maintaining a high-quality electrode-tissue interface and suggest that MT promotes neuroprotection possibly through its anti-apoptotic, anti-inflammatory, and anti-oxidative properties.
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Affiliation(s)
- Asiyeh Golabchi
- Department of Bioengineering, University of Pittsburgh, USA; Center for Neural Basis of Cognition, USA
| | - Bingchen Wu
- Department of Bioengineering, University of Pittsburgh, USA; Center for Neural Basis of Cognition, USA
| | - Xia Li
- Department of Bioengineering, University of Pittsburgh, USA
| | - Diane L Carlisle
- Neuroapoptosis Laboratory, Department of Neurological Surgery, University of Pittsburgh School of Medicine, USA
| | - Takashi D Y Kozai
- Department of Bioengineering, University of Pittsburgh, USA; Center for Neural Basis of Cognition, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, USA; Neurotechnology Division of the University of Pittsburgh Brain Institute, USA
| | - Robert M Friedlander
- Neuroapoptosis Laboratory, Department of Neurological Surgery, University of Pittsburgh School of Medicine, USA
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, USA; Center for Neural Basis of Cognition, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, USA.
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131
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Stiller AM, Usoro J, Frewin CL, Danda VR, Ecker M, Joshi-Imre A, Musselman KC, Voit W, Modi R, Pancrazio JJ, Black BJ. Chronic Intracortical Recording and Electrochemical Stability of Thiol-ene/Acrylate Shape Memory Polymer Electrode Arrays. MICROMACHINES 2018; 9:E500. [PMID: 30424433 PMCID: PMC6215160 DOI: 10.3390/mi9100500] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 09/24/2018] [Accepted: 09/27/2018] [Indexed: 11/20/2022]
Abstract
Current intracortical probe technology is limited in clinical implementation due to the short functional lifetime of implanted devices. Devices often fail several months to years post-implantation, likely due to the chronic immune response characterized by glial scarring and neuronal dieback. It has been demonstrated that this neuroinflammatory response is influenced by the mechanical mismatch between stiff devices and the soft brain tissue, spurring interest in the use of softer polymer materials for probe encapsulation. Here, we demonstrate stable recordings and electrochemical properties obtained from fully encapsulated shape memory polymer (SMP) intracortical electrodes implanted in the rat motor cortex for 13 weeks. SMPs are a class of material that exhibit modulus changes when exposed to specific conditions. The formulation used in these devices softens by an order of magnitude after implantation compared to its dry, room-temperature modulus of ~2 GPa.
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Affiliation(s)
- Allison M Stiller
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Joshua Usoro
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Christopher L Frewin
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Vindhya R Danda
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
- Qualia, Inc., Dallas, TX 75252, USA.
| | - Melanie Ecker
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Alexandra Joshi-Imre
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Kate C Musselman
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Walter Voit
- Qualia, Inc., Dallas, TX 75252, USA.
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | | | - Joseph J Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
| | - Bryan J Black
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA.
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132
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Shoffstall AJ, Ecker M, Danda V, Joshi-Imre A, Stiller A, Yu M, Paiz JE, Mancuso E, Bedell HW, Voit WE, Pancrazio JJ, Capadona JR. Characterization of the Neuroinflammatory Response to Thiol-ene Shape Memory Polymer Coated Intracortical Microelectrodes. MICROMACHINES 2018; 9:E486. [PMID: 30424419 PMCID: PMC6215215 DOI: 10.3390/mi9100486] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/11/2018] [Accepted: 09/18/2018] [Indexed: 01/10/2023]
Abstract
Thiol-ene based shape memory polymers (SMPs) have been developed for use as intracortical microelectrode substrates. The unique chemistry provides precise control over the mechanical and thermal glass-transition properties. As a result, SMP substrates are stiff at room temperature, allowing for insertion into the brain without buckling and subsequently soften in response to body temperatures, reducing the mechanical mismatch between device and tissue. Since the surface chemistry of the materials can contribute significantly to the ultimate biocompatibility, as a first step in the characterization of our SMPs, we sought to isolate the biological response to the implanted material surface without regards to the softening mechanics. To accomplish this, we tightly controlled for bulk stiffness by comparing bare silicon 'dummy' devices to thickness-matched silicon devices dip-coated with SMP. The neuroinflammatory response was evaluated after devices were implanted in the rat cortex for 2 or 16 weeks. We observed no differences in the markers tested at either time point, except that astrocytic scarring was significantly reduced for the dip-coated implants at 16 weeks. The surface properties of non-softening thiol-ene SMP substrates appeared to be equally-tolerated and just as suitable as silicon for neural implant substrates for applications such as intracortical microelectrodes, laying the groundwork for future softer devices to improve upon the prototype device performance presented here.
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Affiliation(s)
- Andrew J Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH, USA.
| | - Melanie Ecker
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH, USA.
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, TX, USA.
| | - Vindhya Danda
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, TX, USA.
- Center for Engineering Innovation, The University of Texas at Dallas, Richardson, TX, USA.
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA.
- Department of Mechanical Engineering, The University of Texas at Dallas, Richardson, TX, USA.
| | - Alexandra Joshi-Imre
- Center for Engineering Innovation, The University of Texas at Dallas, Richardson, TX, USA.
| | - Allison Stiller
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA.
| | - Marina Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH, USA.
| | - Jennifer E Paiz
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH, USA.
| | - Elizabeth Mancuso
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH, USA.
| | - Hillary W Bedell
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
| | - Walter E Voit
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, TX, USA.
- Center for Engineering Innovation, The University of Texas at Dallas, Richardson, TX, USA.
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA.
- Department of Mechanical Engineering, The University of Texas at Dallas, Richardson, TX, USA.
| | - Joseph J Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA.
| | - Jeffrey R Capadona
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH, USA.
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133
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Kozai TDY. The History and Horizons of Microscale Neural Interfaces. MICROMACHINES 2018; 9:E445. [PMID: 30424378 PMCID: PMC6187275 DOI: 10.3390/mi9090445] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 08/27/2018] [Accepted: 09/03/2018] [Indexed: 12/29/2022]
Abstract
Microscale neural technologies interface with the nervous system to record and stimulate brain tissue with high spatial and temporal resolution. These devices are being developed to understand the mechanisms that govern brain function, plasticity and cognitive learning, treat neurological diseases, or monitor and restore functions over the lifetime of the patient. Despite decades of use in basic research over days to months, and the growing prevalence of neuromodulation therapies, in many cases the lack of knowledge regarding the fundamental mechanisms driving activation has dramatically limited our ability to interpret data or fine-tune design parameters to improve long-term performance. While advances in materials, microfabrication techniques, packaging, and understanding of the nervous system has enabled tremendous innovation in the field of neural engineering, many challenges and opportunities remain at the frontiers of the neural interface in terms of both neurobiology and engineering. In this short-communication, we explore critical needs in the neural engineering field to overcome these challenges. Disentangling the complexities involved in the chronic neural interface problem requires simultaneous proficiency in multiple scientific and engineering disciplines. The critical component of advancing neural interface knowledge is to prepare the next wave of investigators who have simultaneous multi-disciplinary proficiencies with a diverse set of perspectives necessary to solve the chronic neural interface challenge.
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Affiliation(s)
- Takashi D Y Kozai
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15213, USA.
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA 15261, USA.
- McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15212, USA.
- NeuroTech Center, University of Pittsburgh Brain Institute, Pittsburgh, PA 15260, USA.
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134
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Goss-Varley M, Shoffstall AJ, Dona KR, McMahon JA, Lindner SC, Ereifej ES, Capadona JR. Rodent Behavioral Testing to Assess Functional Deficits Caused by Microelectrode Implantation in the Rat Motor Cortex. J Vis Exp 2018:57829. [PMID: 30176008 PMCID: PMC6128113 DOI: 10.3791/57829] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Medical devices implanted in the brain hold tremendous potential. As part of a Brain Machine Interface (BMI) system, intracortical microelectrodes demonstrate the ability to record action potentials from individual or small groups of neurons. Such recorded signals have successfully been used to allow patients to interface with or control computers, robotic limbs, and their own limbs. However, previous animal studies have shown that a microelectrode implantation in the brain not only damages the surrounding tissue but can also result in functional deficits. Here, we discuss a series of behavioral tests to quantify potential motor impairments following the implantation of intracortical microelectrodes into the motor cortex of a rat. The methods for open field grid, ladder crossing, and grip strength testing provide valuable information regarding the potential complications resulting from a microelectrode implantation. The results of the behavioral testing are correlated with endpoint histology, providing additional information on the pathological outcomes and impacts of this procedure on the adjacent tissue.
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Affiliation(s)
- Monika Goss-Varley
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Andrew J Shoffstall
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Keith R Dona
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Justin A McMahon
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Sydney C Lindner
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Evon S Ereifej
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Jeffrey R Capadona
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University;
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135
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Bernardin EK, Frewin CL, Everly R, Ul Hassan J, Saddow SE. Demonstration of a Robust All-Silicon-Carbide Intracortical Neural Interface. MICROMACHINES 2018; 9:E412. [PMID: 30424345 PMCID: PMC6187288 DOI: 10.3390/mi9080412] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 08/11/2018] [Accepted: 08/12/2018] [Indexed: 01/09/2023]
Abstract
Intracortical neural interfaces (INI) have made impressive progress in recent years but still display questionable long-term reliability. Here, we report on the development and characterization of highly resilient monolithic silicon carbide (SiC) neural devices. SiC is a physically robust, biocompatible, and chemically inert semiconductor. The device support was micromachined from p-type SiC with conductors created from n-type SiC, simultaneously providing electrical isolation through the resulting p-n junction. Electrodes possessed geometric surface area (GSA) varying from 496 to 500 K μm². Electrical characterization showed high-performance p-n diode behavior, with typical turn-on voltages of ~2.3 V and reverse bias leakage below 1 nArms. Current leakage between adjacent electrodes was ~7.5 nArms over a voltage range of -50 V to 50 V. The devices interacted electrochemically with a purely capacitive relationship at frequencies less than 10 kHz. Electrode impedance ranged from 675 ± 130 kΩ (GSA = 496 µm²) to 46.5 ± 4.80 kΩ (GSA = 500 K µm²). Since the all-SiC devices rely on the integration of only robust and highly compatible SiC material, they offer a promising solution to probe delamination and biological rejection associated with the use of multiple materials used in many current INI devices.
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Affiliation(s)
- Evans K Bernardin
- Department of Biomedical Engineering, University of South Florida, Tampa, FL 33620, USA.
| | - Christopher L Frewin
- Department of Bioengineering, University of Texas at Dallas, Dallas, TX 75080, USA.
| | - Richard Everly
- Nanotechnology Research and Education Center @ USF, Tampa, FL 33617, USA.
| | - Jawad Ul Hassan
- Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden.
| | - Stephen E Saddow
- Department of Electrical Engineering, University of South Florida, Tampa, FL 33620, USA.
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Hermann JK, Lin S, Soffer A, Wong C, Srivastava V, Chang J, Sunil S, Sudhakar S, Tomaszewski WH, Protasiewicz G, Selkirk SM, Miller RH, Capadona JR. The Role of Toll-Like Receptor 2 and 4 Innate Immunity Pathways in Intracortical Microelectrode-Induced Neuroinflammation. Front Bioeng Biotechnol 2018; 6:113. [PMID: 30159311 PMCID: PMC6104445 DOI: 10.3389/fbioe.2018.00113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 07/19/2018] [Indexed: 12/13/2022] Open
Abstract
We have recently demonstrated that partial inhibition of the cluster of differentiation 14 (CD14) innate immunity co-receptor pathway improves the long-term performance of intracortical microelectrodes better than complete inhibition. We hypothesized that partial activation of the CD14 pathway was critical to a neuroprotective response to the injury associated with initial and sustained device implantation. Therefore, here we investigated the role of two innate immunity receptors that closely interact with CD14 in inflammatory activation. We implanted silicon planar non-recording neural probes into knockout mice lacking Toll-like receptor 2 (Tlr2-/-), knockout mice lacking Toll-like receptor 4 (Tlr4-/-), and wildtype (WT) control mice, and evaluated endpoint histology at 2 and 16 weeks after implantation. Tlr4-/- mice exhibited significantly lower BBB permeability at acute and chronic time points, but also demonstrated significantly lower neuronal survival at the chronic time point. Inhibition of the Toll-like receptor 2 (TLR2) pathway had no significant effect compared to control animals. Additionally, when investigating the maturation of the neuroinflammatory response from 2 to 16 weeks, transgenic knockout mice exhibited similar histological trends to WT controls, except that knockout mice did not exhibit changes in microglia and macrophage activation over time. Together, our results indicate that complete genetic removal of Toll-like receptor 4 (TLR4) was detrimental to the integration of intracortical neural probes, while inhibition of TLR2 had no impact within the tests performed in this study. Therefore, approaches focusing on incomplete or acute inhibition of TLR4 may still improve intracortical microelectrode integration and long term recording performance.
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Affiliation(s)
- John K. Hermann
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Shushen Lin
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Arielle Soffer
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Chun Wong
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Vishnupriya Srivastava
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Jeremy Chang
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Smrithi Sunil
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Shruti Sudhakar
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - William H. Tomaszewski
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Grace Protasiewicz
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Stephen M. Selkirk
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
- Department of Neurology, Case Western Reserve University, Cleveland, OH, United States
- Spinal Cord Injury Division, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Robert H. Miller
- Neurosciences, George Washington University, Washington, DC, United States
| | - Jeffrey R. Capadona
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, United States
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137
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Eles JR, Vazquez AL, Kozai TDY, Cui XT. In vivo imaging of neuronal calcium during electrode implantation: Spatial and temporal mapping of damage and recovery. Biomaterials 2018; 174:79-94. [PMID: 29783119 PMCID: PMC5987772 DOI: 10.1016/j.biomaterials.2018.04.043] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/16/2018] [Accepted: 04/21/2018] [Indexed: 12/13/2022]
Abstract
Implantable electrode devices enable long-term electrophysiological recordings for brain-machine interfaces and basic neuroscience research. Implantation of these devices, however, leads to neuronal damage and progressive neural degeneration that can lead to device failure. The present study uses in vivo two-photon microscopy to study the calcium activity and morphology of neurons before, during, and one month after electrode implantation to determine how implantation trauma injures neurons. We show that implantation leads to prolonged, elevated calcium levels in neurons within 150 μm of the electrode interface. These neurons show signs of mechanical distortion and mechanoporation after implantation, suggesting that calcium influx is related to mechanical trauma. Further, calcium-laden neurites develop signs of axonal injury at 1-3 h post-insert. Over the first month after implantation, physiological neuronal calcium activity increases, suggesting that neurons may be recovering. By defining the mechanisms of neuron damage after electrode implantation, our results suggest new directions for therapies to improve electrode longevity.
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Affiliation(s)
- James R Eles
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States
| | - Alberto L Vazquez
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States; Radiology, University of Pittsburgh, United States
| | - Takashi D Y Kozai
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, United States; NeuroTech Center of the University of Pittsburgh Brain Institute, United States; Center for Neuroscience, University of Pittsburgh, United States
| | - X Tracy Cui
- Bioengineering, University of Pittsburgh, United States; Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, United States.
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138
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Zhang M, Schwemmer MA, Ting JE, Majstorovic CE, Friedenberg DA, Bockbrader MA, Jerry Mysiw W, Rezai AR, Annetta NV, Bouton CE, Bresler HS, Sharma G. Extracting wavelet based neural features from human intracortical recordings for neuroprosthetics applications. Bioelectron Med 2018; 4:11. [PMID: 32232087 PMCID: PMC7098253 DOI: 10.1186/s42234-018-0011-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/17/2018] [Indexed: 12/15/2022] Open
Abstract
Background Understanding the long-term behavior of intracortically-recorded signals is essential for improving the performance of Brain Computer Interfaces. However, few studies have systematically investigated chronic neural recordings from an implanted microelectrode array in the human brain. Methods In this study, we show the applicability of wavelet decomposition method to extract and demonstrate the utility of long-term stable features in neural signals obtained from a microelectrode array implanted in the motor cortex of a human with tetraplegia. Wavelet decomposition was applied to the raw voltage data to generate mean wavelet power (MWP) features, which were further divided into three sub-frequency bands, low-frequency MWP (lf-MWP, 0–234 Hz), mid-frequency MWP (mf-MWP, 234 Hz–3.75 kHz) and high-frequency MWP (hf-MWP, >3.75 kHz). We analyzed these features using data collected from two experiments that were repeated over the course of about 3 years and compared their signal stability and decoding performance with the more standard threshold crossings, local field potentials (LFP), multi-unit activity (MUA) features obtained from the raw voltage recordings. Results All neural features could stably track neural information for over 3 years post-implantation and were less prone to signal degradation compared to threshold crossings. Furthermore, when used as an input to support vector machine based decoding algorithms, the mf-MWP and MUA demonstrated significantly better performance, respectively, in classifying imagined motor tasks than using the lf-MWP, hf-MWP, LFP, or threshold crossings. Conclusions Our results suggest that using MWP features in the appropriate frequency bands can provide an effective neural feature for brain computer interface intended for chronic applications. Trial registration This study was approved by the U.S. Food and Drug Administration (Investigational Device Exemption) and the Ohio State University Medical Center Institutional Review Board (Columbus, Ohio). The study conformed to institutional requirements for the conduct of human subjects and was filed on ClinicalTrials.gov (Identifier NCT01997125). Electronic supplementary material The online version of this article (10.1186/s42234-018-0011-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mingming Zhang
- 1Battelle Memorial Institute, 505 King Ave, Columbus, OH 43021 USA
| | | | - Jordyn E Ting
- 1Battelle Memorial Institute, 505 King Ave, Columbus, OH 43021 USA
| | | | | | - Marcia A Bockbrader
- 2Department of Physical Medicine and Rehabilitation, The Ohio State University, Columbus, OH 43210 USA
| | - W Jerry Mysiw
- 2Department of Physical Medicine and Rehabilitation, The Ohio State University, Columbus, OH 43210 USA
| | - Ali R Rezai
- 3West Virginia University School of Medicine, 1 Medical Center Dr, Morgantown, WV 26506 USA
| | | | - Chad E Bouton
- 4Feinstein Institute for Medical Research, Manhasset, NY 11030 USA
| | | | - Gaurav Sharma
- 1Battelle Memorial Institute, 505 King Ave, Columbus, OH 43021 USA
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139
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Michelson NJ, Vazquez AL, Eles JR, Salatino JW, Purcell EK, Williams JJ, Cui XT, Kozai TDY. Multi-scale, multi-modal analysis uncovers complex relationship at the brain tissue-implant neural interface: new emphasis on the biological interface. J Neural Eng 2018; 15:033001. [PMID: 29182149 PMCID: PMC5967409 DOI: 10.1088/1741-2552/aa9dae] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Implantable neural electrode devices are important tools for neuroscience research and have an increasing range of clinical applications. However, the intricacies of the biological response after implantation, and their ultimate impact on recording performance, remain challenging to elucidate. Establishing a relationship between the neurobiology and chronic recording performance is confounded by technical challenges related to traditional electrophysiological, material, and histological limitations. This can greatly impact the interpretations of results pertaining to device performance and tissue health surrounding the implant. APPROACH In this work, electrophysiological activity and immunohistological analysis are compared after controlling for motion artifacts, quiescent neuronal activity, and material failure of devices in order to better understand the relationship between histology and electrophysiological outcomes. MAIN RESULTS Even after carefully accounting for these factors, the presence of viable neurons and lack of glial scarring does not convey single unit recording performance. SIGNIFICANCE To better understand the biological factors influencing neural activity, detailed cellular and molecular tissue responses were examined. Decreases in neural activity and blood oxygenation in the tissue surrounding the implant, shift in expression levels of vesicular transporter proteins and ion channels, axon and myelin injury, and interrupted blood flow in nearby capillaries can impact neural activity around implanted neural interfaces. Combined, these tissue changes highlight the need for more comprehensive, basic science research to elucidate the relationship between biology and chronic electrophysiology performance in order to advance neural technologies.
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Affiliation(s)
| | - Alberto L Vazquez
- Department of Bioengineering, University of Pittsburgh
- Department of Radiology, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
- Center for Neuroscience, University of Pittsburgh
| | - James R Eles
- Department of Bioengineering, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
| | | | - Erin K Purcell
- Department of Biomedical Engineering, Michigan State University
| | | | - X. Tracy Cui
- Department of Bioengineering, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
- McGowan Institute of Regenerative Medicine, University of Pittsburgh
| | - Takashi DY Kozai
- Department of Bioengineering, University of Pittsburgh
- Center for the Neural Basis of Cognition, University of Pittsburgh
- Center for Neuroscience, University of Pittsburgh
- McGowan Institute of Regenerative Medicine, University of Pittsburgh
- NeuroTech Center, University of Pittsburgh Brain Institute
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140
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Chen G, Dodson B, Hedges DM, Steffensen SC, Harb JN, Puleo C, Galligan C, Ashe J, Vanfleet RR, Davis RC. Fabrication of High Aspect Ratio Millimeter-Tall Free-Standing Carbon Nanotube-Based Microelectrode Arrays. ACS Biomater Sci Eng 2018; 4:1900-1907. [PMID: 33445345 DOI: 10.1021/acsbiomaterials.8b00038] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Microelectrode arrays of carbon nanotube (CNT)/carbon composite posts with high aspect ratio and millimeter-length were fabricated using carbon-nanotube-templated microfabrication with a sacrificial "hedge". The high aspect ratio, mechanical robustness, and electrical conductivity of these electrodes make them a potential candidate for next-generation neural interfacing. Electrochemical measurements were also demonstrated using an individual CNT post microelectrode with a diameter of 25 μm and a length of 1 mm to perform cyclic voltammetry on both methyl viologen and dopamine in a phosphate-buffered saline solution. In addition to detection of the characteristic peaks, the CNT post microelectrodes show a fast electrochemical response, which may be enabling for in vivo and/or in vitro measurements. The CNT post electrode fabrication process was also integrated with other microfabrication techniques, resulting in individually addressable electrodes.
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Affiliation(s)
- Guohai Chen
- Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, United States
| | - Berg Dodson
- Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, United States
| | - David M Hedges
- Department of Psychology and Neuroscience, Brigham Young University, Provo, Utah 84602, United States
| | - Scott C Steffensen
- Department of Psychology and Neuroscience, Brigham Young University, Provo, Utah 84602, United States
| | - John N Harb
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Chris Puleo
- General Electric Global Research (GE-GR), 1 Research Circle, Niskayuna, New York 12309, United States
| | - Craig Galligan
- General Electric Global Research (GE-GR), 1 Research Circle, Niskayuna, New York 12309, United States
| | - Jeffrey Ashe
- General Electric Global Research (GE-GR), 1 Research Circle, Niskayuna, New York 12309, United States
| | - Richard R Vanfleet
- Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, United States
| | - Robert C Davis
- Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, United States
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141
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Ibrahim A, Meng M, Kiani M. A Comprehensive Comparative Study on Inductive and Ultrasonic Wireless Power Transmission to Biomedical Implants. IEEE SENSORS JOURNAL 2018; 18:3813-3826. [PMID: 30344453 PMCID: PMC6192045 DOI: 10.1109/jsen.2018.2812420] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This paper presents a comprehensive comparison between inductive coupling and ultrasound for wireless power transmission (WPT) to biomedical implants. Several sets of inductive and ultrasonic links for different powering distances (d 12) and receiver dimensions have been optimized, and their key parameters, including power transmission efficiency (PTE) and power delivered to the load (PDL) within safety constraints, have been compared to find out which method is optimal for any given condition. Two design procedures have been presented for maximizing the PTE of inductive and ultrasonic links by finding the optimal geometry for the transmitter (Tx) and receiver (Rx) coils and ultrasonic transducers as well as the optimal operation frequency (fp ). Our simulation and measurement results showed that the ultrasonic link transcends the inductive link in PTE and somewhat in PDL for a small Rx of 1.1 mm3 (diameter of 1.2 mm), particularly when the Rx was deeply implanted inside the tissue (d 12 ≥ 10 mm). However, for a larger 20 mm3 Rx (diameter of 5 mm), the inductive link achieved higher PTE and PDL, particularly at shorter distances (d 12 < 30 mm). The optimal loading condition is shown to be quite different in inductive and ultrasonic links. Despite higher performance for small Rx and large d 12, the ultrasonic link is more sensitive to Rx misalignments and orientations. This led us to propose a new design procedure based on the worst-case misalignment scenario. The simulation results have been validated by measurements. The inductive and ultrasonic links, operating at 30 MHz and 1.1 MHz, achieved measured PTEs of 0.05% and 0.65% for the 1.1 mm3 Rx located 30 mm inside tissue and oil environments with optimal load resistances of 295 Ω and 3.8 kΩ, respectively.
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Affiliation(s)
- Ahmed Ibrahim
- Electrical Engineering Department at the Pennsylvania State University, University Park, PA 16802, USA
| | - Miao Meng
- Electrical Engineering Department at the Pennsylvania State University, University Park, PA 16802, USA
| | - Mehdi Kiani
- Electrical Engineering Department at the Pennsylvania State University, University Park, PA 16802, USA
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142
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Bedell HW, Hermann JK, Ravikumar M, Lin S, Rein A, Li X, Molinich E, Smith PD, Selkirk SM, Miller RH, Sidik S, Taylor DM, Capadona JR. Targeting CD14 on blood derived cells improves intracortical microelectrode performance. Biomaterials 2018; 163:163-173. [PMID: 29471127 PMCID: PMC5841759 DOI: 10.1016/j.biomaterials.2018.02.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/31/2018] [Accepted: 02/07/2018] [Indexed: 01/02/2023]
Abstract
Intracortical microelectrodes afford researchers an effective tool to precisely monitor neural spiking activity. Additionally, intracortical microelectrodes have the ability to return function to individuals with paralysis as part of a brain computer interface. Unfortunately, the neural signals recorded by these electrodes degrade over time. Many strategies which target the biological and/or materials mediating failure modes of this decline of function are currently under investigation. The goal of this study is to identify a precise cellular target for future intervention to sustain chronic intracortical microelectrode performance. Previous work from our lab has indicated that the Cluster of Differentiation 14/Toll-like receptor pathway (CD14/TLR) is a viable target to improve chronic laminar, silicon intracortical microelectrode recordings. Here, we use a mouse bone marrow chimera model to selectively knockout CD14, an innate immune receptor, from either brain resident microglia or blood-derived macrophages, in order to understand the most effective targets for future therapeutic options. Using single-unit recordings we demonstrate that inhibiting CD14 from the blood-derived macrophages improves recording quality over the 16 week long study. We conclude that targeting CD14 in blood-derived cells should be part of the strategy to improve the performance of intracortical microelectrodes, and that the daunting task of delivering therapeutics across the blood-brain barrier may not be needed to increase intracortical microelectrode performance.
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Affiliation(s)
- Hillary W Bedell
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA; Advanced Platform Technology Center, L. Stokes Cleveland VA Medical Center, Rehab. R&D, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106, USA
| | - John K Hermann
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA; Advanced Platform Technology Center, L. Stokes Cleveland VA Medical Center, Rehab. R&D, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106, USA
| | - Madhumitha Ravikumar
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA; Advanced Platform Technology Center, L. Stokes Cleveland VA Medical Center, Rehab. R&D, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106, USA
| | - Shushen Lin
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA
| | - Ashley Rein
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA
| | - Xujia Li
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA
| | - Emily Molinich
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA
| | - Patrick D Smith
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA
| | - Stephen M Selkirk
- Advanced Platform Technology Center, L. Stokes Cleveland VA Medical Center, Rehab. R&D, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106, USA
| | - Robert H Miller
- Neurosciences, The George Washington University, The School of Medicine & Health Sciences, 2300 Eye Street, NW, Ross Hall, Washington DC 20037, USA
| | - Steven Sidik
- Department of Mathematics, Applied Mathematics and Statistics, Case Western Reserve University, 2049 Martin Luther King Jr. Drive, Yost Hall, Cleveland, OH 44106, USA
| | - Dawn M Taylor
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA; Department of Neurosciences, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Jeffrey R Capadona
- Department of Biomedical Engineering, Case Western Reserve University, School of Engineering, 2071 MLK Jr. Drive, Wickenden Bldg, Cleveland, OH 44106, USA; Advanced Platform Technology Center, L. Stokes Cleveland VA Medical Center, Rehab. R&D, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106, USA.
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143
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Deep Brain Stimulation associated gliosis: A post-mortem study. Parkinsonism Relat Disord 2018; 54:51-55. [PMID: 29653910 DOI: 10.1016/j.parkreldis.2018.04.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 03/19/2018] [Accepted: 04/03/2018] [Indexed: 11/21/2022]
Abstract
BACKGROUND DBS is a well-established therapy for patients with PD and is an emerging therapy for other neuropsychiatric disorders. Despite the rise in DBS usage, relatively little is known about the tissue and cellular responses to DBS. PURPOSE To examine post-mortem effects of DBS leads by objectively quantifying gliosis around the distal DBS lead tip. METHODS The UF DBS Brain Bank repository currently has 64 brains, of which 18 cases met criteria for this study. RESULTS The average patient age was 54.88 ± 13.43 years (mean ± SD), male:female ratio was 3:1, average disease duration was 20.70 ± 6.36 years and average DBS duration was 7.26 ± 6.36 years. Microscopic evaluation revealed tissue reaction and astrocytic responses to the lead. Significant fibrosis was seen in n = 2 brains and prominent microglial response in n = 1. Mean gliotic collar measured from H&E and GFAP staining was 122.5 μm and 162.5 μm, respectively. Mean gliotic thickness at the DBS electrode lead tip was 119.13 ± 64.29 μm for patients receiving DBS for 0-5 years, 127.85 ± 94.34 μm for 5-10 years and 111.73 ± 114.18 μm for patients with DBS >10 years. Kruskal-Wallis one-way analysis of variance (ANOVA) revealed no statistically significant differences between DBS duration and amount of gliosis. CONCLUSIONS This study revealed that approximately three out of four post-mortem DBS cases exhibited pathological evidence of a glial collar or scar present at the ventral DBS lead tip. The amount of gliosis was not significantly associated with duration of DBS. Future studies should include serial sectioning across all DBS contacts with correlation to the volume of tissue activation and to the clinical outcome.
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144
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Falcone JD, Carroll SL, Saxena T, Mandavia D, Clark A, Yarabarla V, Bellamkonda RV. Correlation of mRNA Expression and Signal Variability in Chronic Intracortical Electrodes. Front Bioeng Biotechnol 2018; 6:26. [PMID: 29637071 PMCID: PMC5880884 DOI: 10.3389/fbioe.2018.00026] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 03/06/2018] [Indexed: 01/08/2023] Open
Abstract
Objective The goal for this research was to identify molecular mechanisms that explain animal-to-animal variability in chronic intracortical recordings. Approach Microwire electrodes were implanted into Sprague Dawley rats at an acute (1 week) and a chronic (14 weeks) time point. Weekly recordings were conducted, and action potentials were evoked in the barrel cortex by deflecting the rat’s whiskers. At 1 and 14 weeks, tissue was collected, and mRNA was extracted. mRNA expression was compared between 1 and 14 weeks using a high throughput multiplexed qRT-PCR. Pearson correlation coefficients were calculated between mRNA expression and signal-to-noise ratios at 14 weeks. Main results At 14 weeks, a positive correlation between signal-to-noise ratio (SNR) and NeuN and GFAP mRNA expression was observed, indicating a relationship between recording strength and neuronal population, as well as reactive astrocyte activity. The inflammatory state around the electrode interface was evaluated using M1-like and M2-like markers. Expression for both M1-like and M2-like mRNA markers remained steady from 1 to 14 weeks. Anti-inflammatory markers, CD206 and CD163, however, demonstrated a significant positive correlation with SNR quality at 14 weeks. VE-cadherin, a marker for adherens junctions, and PDGFR-β, a marker for pericytes, both partial representatives of blood–brain barrier health, had a positive correlation with SNR at 14 weeks. Endothelial adhesion markers revealed a significant increase in expression at 14 weeks, while CD45, a pan-leukocyte marker, significantly decreased at 14 weeks. No significant correlation was found for either the endothelial adhesion or pan-leukocyte markers. Significance A positive correlation between anti-inflammatory and blood–brain barrier health mRNA markers with electrophysiological efficacy of implanted intracortical electrodes has been demonstrated. These data reveal potential mechanisms for further evaluation to determine potential target mechanisms to improve consistency of intracortical electrodes recordings and reduce animal-to-animal/implant-to-implant variability.
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Affiliation(s)
- Jessica D Falcone
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Sheridan L Carroll
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Tarun Saxena
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Dev Mandavia
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Alexus Clark
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Varun Yarabarla
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
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145
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Wellman SM, Eles JR, Ludwig KA, Seymour JP, Michelson NJ, McFadden WE, Vazquez AL, Kozai TDY. A Materials Roadmap to Functional Neural Interface Design. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1701269. [PMID: 29805350 PMCID: PMC5963731 DOI: 10.1002/adfm.201701269] [Citation(s) in RCA: 181] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Advancement in neurotechnologies for electrophysiology, neurochemical sensing, neuromodulation, and optogenetics are revolutionizing scientific understanding of the brain while enabling treatments, cures, and preventative measures for a variety of neurological disorders. The grand challenge in neural interface engineering is to seamlessly integrate the interface between neurobiology and engineered technology, to record from and modulate neurons over chronic timescales. However, the biological inflammatory response to implants, neural degeneration, and long-term material stability diminish the quality of interface overtime. Recent advances in functional materials have been aimed at engineering solutions for chronic neural interfaces. Yet, the development and deployment of neural interfaces designed from novel materials have introduced new challenges that have largely avoided being addressed. Many engineering efforts that solely focus on optimizing individual probe design parameters, such as softness or flexibility, downplay critical multi-dimensional interactions between different physical properties of the device that contribute to overall performance and biocompatibility. Moreover, the use of these new materials present substantial new difficulties that must be addressed before regulatory approval for use in human patients will be achievable. In this review, the interdependence of different electrode components are highlighted to demonstrate the current materials-based challenges facing the field of neural interface engineering.
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Affiliation(s)
- Steven M Wellman
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - James R Eles
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - Kip A Ludwig
- Department of Neurologic Surgery, 200 First St. SW, Rochester, MN 55905
| | - John P Seymour
- Electrical & Computer Engineering, 1301 Beal Ave., 2227 EECS, Ann Arbor, MI 48109
| | - Nicholas J Michelson
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - William E McFadden
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - Alberto L Vazquez
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
| | - Takashi D Y Kozai
- Department of Bioengineering, Center for the Basis of Neural Cognition, McGowan Institute of Regenerative Medicine, NeuroTech Center, University of Pittsburgh Brain Institute, Center for Neuroscience at the University of Pittsburgh, University of Pittsburgh, 208 Center for Biotechnology, 300 Technology Dr., Pittsburgh, PA 15219, United States
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146
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Wang J, Thow XY, Wang H, Lee S, Voges K, Thakor NV, Yen SC, Lee C. A Highly Selective 3D Spiked Ultraflexible Neural (SUN) Interface for Decoding Peripheral Nerve Sensory Information. Adv Healthc Mater 2018; 7. [PMID: 29205933 DOI: 10.1002/adhm.201700987] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 09/04/2017] [Indexed: 01/06/2023]
Abstract
Artificial sensors on the skin are proposed as a way to capture information that can be used in intracortical microstimulation or peripheral intraneural stimulation to restore sensory feedback to persons with tetraplegia. However, the ability of these artificial sensors to replicate the density and complexity of the natural mechanoreceptors is limited. One relatively unexplored approach is to make use of the signals from surviving tactile and proprioceptive receptors in existing limbs by recording from their transmitting axons within the primary sensory nerves. Here, a novel spiked ultraflexible neural (SUN) interface that is implanted into the peripheral nervous system to capture sensory information from these mechanoreceptors in acute rat experiments is described. The novel 3D design, which integrates spiked structures for intrafascicular nerve recording with an ultraflexible substrate, enables a unique conformal interface to the target nerve. With the high-quality recording (average signal-to-noise-ratio of 1.4) provided by the electrode, tactile from proprioceptive stimuli can be differentiated in terms of the firing rate. In toe pinching experiments, high spatial resolution classification can be achieved with support vector machine classifier. Further work remains to be done to assess the chronic recording capability of the SUN interface.
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Affiliation(s)
- Jiahui Wang
- Department of Electrical and Computer Engineering; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
- Center for Intelligent Sensors and MEMS; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
| | - Xin Yuan Thow
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
| | - Hao Wang
- Department of Electrical and Computer Engineering; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
- Center for Intelligent Sensors and MEMS; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
| | - Sanghoon Lee
- Department of Electrical and Computer Engineering; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
- Center for Intelligent Sensors and MEMS; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
| | - Kai Voges
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
| | - Nitish V. Thakor
- Department of Electrical and Computer Engineering; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
| | - Shih-Cheng Yen
- Department of Electrical and Computer Engineering; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
- Center for Intelligent Sensors and MEMS; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
| | - Chengkuo Lee
- Department of Electrical and Computer Engineering; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
- Singapore Institute for Neurotechnology (SINAPSE); National University of Singapore; 28 Medical Drive, #05-COR Singapore 117456 Singapore
- Center for Intelligent Sensors and MEMS; National University of Singapore; 4 Engineering Drive 3 Singapore 117576 Singapore
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147
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Bennett C, Samikkannu M, Mohammed F, Dietrich WD, Rajguru SM, Prasad A. Blood brain barrier (BBB)-disruption in intracortical silicon microelectrode implants. Biomaterials 2018; 164:1-10. [PMID: 29477707 DOI: 10.1016/j.biomaterials.2018.02.036] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 02/15/2018] [Accepted: 02/18/2018] [Indexed: 12/16/2022]
Abstract
Chronically implanted microelectrodes in the neural tissue elicit inflammatory responses that are time varying and have been shown to depend on multiple factors. Among these factors, blood brain barrier (BBB)-disruption has been hypothesized as one of the dominant factors resulting in electrode failure. A series of events that includes BBB and cell-membrane disruption occurs during electrode implantation that triggers multiple biochemical cascades responsible for microglial and astroglial activation, hemorrhage, edema, and release of pro-inflammatory neurotoxic cytokines that causes neuronal degeneration and dysfunction. Typically, microwire arrays and silicon probes are inserted slowly into the neural tissue whereas the silicon Utah MEAs (UMEA) are inserted at a high speed using a pneumatic inserter. In this work, we report the sequelae of electrode-implant induced cortical injury at various acute time points in UMEAs implanted in the brain tissue by quantifying the expression profile for key genes mediating the inflammatory response and tight junction (TJ) and adherens junction (AJ) proteins that form the BBB and are critical to the functioning of the BBB. Our results indicated upregulation of most pro-inflammatory genes relative to naïve controls for all time points. Expression levels for the genes that form the TJ and AJ were downregulated suggestive of BBB-dysfunction. Moreover, there was no significant difference between stab and implant groups suggesting the effects of UMEA insertion-related trauma in the brain tissue. Our results provide an insight into the physiological events related to neuroinflammation and BBB-disruption occurring at acute time-points following insertion of UMEAs.
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Affiliation(s)
- Cassie Bennett
- Department of Biomedical Engineering, University of Miami, FL, USA
| | | | | | | | - Suhrud M Rajguru
- Department of Biomedical Engineering, University of Miami, FL, USA; Department of Otolaryngology, University of Miami, FL, USA
| | - Abhishek Prasad
- Department of Biomedical Engineering, University of Miami, FL, USA.
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148
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Ereifej ES, Rial GM, Hermann JK, Smith CS, Meade SM, Rayyan JM, Chen K, Feng H, Capadona JR. Implantation of Neural Probes in the Brain Elicits Oxidative Stress. Front Bioeng Biotechnol 2018; 6:9. [PMID: 29487848 PMCID: PMC5816578 DOI: 10.3389/fbioe.2018.00009] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/22/2018] [Indexed: 12/11/2022] Open
Abstract
Clinical implantation of intracortical microelectrodes has been hindered, at least in part, by the perpetual inflammatory response occurring after device implantation. The neuroinflammatory response observed after device implantation has been correlated to oxidative stress that occurs due to neurological injury and disease. However, there has yet to be a definitive link of oxidative stress to intracortical microelectrode implantation. Thus, the objective of this study is to give direct evidence of oxidative stress following intracortical microelectrode implantation. This study also aims to identify potential molecular targets to attenuate oxidative stress observed postimplantation. Here, we implanted adult rats with silicon non-functional microelectrode probes for 4 weeks and compared the oxidative stress response to no surgery controls through postmortem gene expression analysis and qualitative histological observation of oxidative stress markers. Gene expression analysis results at 4 weeks postimplantation indicated that EH domain-containing 2, prion protein gene (Prnp), and Stearoyl-Coenzyme A desaturase 1 (Scd1) were all significantly higher for animals implanted with intracortical microelectrode probes compared to no surgery control animals. To the contrary, NADPH oxidase activator 1 (Noxa1) relative gene expression was significantly lower for implanted animals compared to no surgery control animals. Histological observation of oxidative stress showed an increased expression of oxidized proteins, lipids, and nucleic acids concentrated around the implant site. Collectively, our results reveal there is a presence of oxidative stress following intracortical microelectrode implantation compared to no surgery controls. Further investigation targeting these specific oxidative stress linked genes could be beneficial to understanding potential mechanisms and downstream therapeutics that can be utilized to reduce oxidative stress-mediated damage following microelectrode implantation.
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Affiliation(s)
- Evon S. Ereifej
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Griffin M. Rial
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - John K. Hermann
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Cara S. Smith
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Seth M. Meade
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Jacob M. Rayyan
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Keying Chen
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - He Feng
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
| | - Jeffrey R. Capadona
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
- Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, United States
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149
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Bouton CE. Advances in Invasive Brain–Computer Interface Technology and Decoding Methods for Restoring Movement and Future Applications. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00029-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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150
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Scaini D, Ballerini L. Nanomaterials at the neural interface. Curr Opin Neurobiol 2017; 50:50-55. [PMID: 29289930 DOI: 10.1016/j.conb.2017.12.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/26/2017] [Accepted: 12/15/2017] [Indexed: 12/16/2022]
Abstract
Interfacing the nervous system with devices able to efficiently record or modulate the electrical activity of neuronal cells represents the underlying foundation of future theranostic applications in neurology and of current openings in neuroscience research. These devices, usually sensing cell activity via microelectrodes, should be characterized by safe working conditions in the biological milieu together with a well-controlled operation-life. The stable device/neuronal electrical coupling at the interface requires tight interactions between the electrode surface and the cell membrane. This neuro-electrode hybrid represents the hyphen between the soft nature of neural tissue, generating electrical signals via ion motions, and the rigid realm of microelectronics and medical devices, dealing with electrons in motion. Efficient integration of these entities is essential for monitoring, analyzing and controlling neuronal signaling but poses significant technological challenges. Improving the cell/electrode interaction and thus the interface performance requires novel engineering of (nano)materials: tuning at the nanoscale electrode's properties may lead to engineer interfacing probes that better camouflaged with their biological target. In this brief review, we highlight the most recent concepts in nanotechnologies and nanomaterials that might help reducing the mismatch between tissue and electrode, focusing on the device's mechanical properties and its biological integration with the tissue.
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Affiliation(s)
- Denis Scaini
- Scuola Internazionale Superiore di Studi Avanzati, via Bonomea, 265, 34136 Trieste, Italy; Elettra-Sincrotrone Trieste S.C.p.A. di interesse nazionale, S.S. 14, km 163,5 in AREA Science Park, 34149 Basovizza, Trieste, Italy
| | - Laura Ballerini
- Scuola Internazionale Superiore di Studi Avanzati, via Bonomea, 265, 34136 Trieste, Italy.
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