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Johnsen KA, Cruzado NA, Menard ZC, Willats AA, Charles AS, Markowitz JE, Rozell CJ. Bridging model and experiment in systems neuroscience with Cleo: the Closed-Loop, Electrophysiology, and Optophysiology simulation testbed. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.27.525963. [PMID: 39026717 PMCID: PMC11257437 DOI: 10.1101/2023.01.27.525963] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Systems neuroscience has experienced an explosion of new tools for reading and writing neural activity, enabling exciting new experiments such as all-optical or closed-loop control that effect powerful causal interventions. At the same time, improved computational models are capable of reproducing behavior and neural activity with increasing fidelity. Unfortunately, these advances have drastically increased the complexity of integrating different lines of research, resulting in the missed opportunities and untapped potential of suboptimal experiments. Experiment simulation can help bridge this gap, allowing model and experiment to better inform each other by providing a low-cost testbed for experiment design, model validation, and methods engineering. Specifically, this can be achieved by incorporating the simulation of the experimental interface into our models, but no existing tool integrates optogenetics, two-photon calcium imaging, electrode recording, and flexible closed-loop processing with neural population simulations. To address this need, we have developed Cleo: the Closed-Loop, Electrophysiology, and Optophysiology experiment simulation testbed. Cleo is a Python package enabling injection of recording and stimulation devices as well as closed-loop control with realistic latency into a Brian spiking neural network model. It is the only publicly available tool currently supporting two-photon and multi-opsin/wavelength optogenetics. To facilitate adoption and extension by the community, Cleo is open-source, modular, tested, and documented, and can export results to various data formats. Here we describe the design and features of Cleo, validate output of individual components and integrated experiments, and demonstrate its utility for advancing optogenetic techniques in prospective experiments using previously published systems neuroscience models.
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Affiliation(s)
- Kyle A. Johnsen
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | | | - Zachary C. Menard
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Adam A. Willats
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Adam S. Charles
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, USA
| | - Jeffrey E. Markowitz
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
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Guo R, Sorenson R, Scharf R, Koch A, Groover A, Sieburth L, Blair S, Menon R. Overcoming the field-of-view to diameter trade-off in microendoscopy via computational optrode-array microscopy. OPTICS EXPRESS 2023; 31:7505-7514. [PMID: 36859879 PMCID: PMC10018790 DOI: 10.1364/oe.478314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/28/2022] [Accepted: 12/09/2022] [Indexed: 06/18/2023]
Abstract
High-resolution microscopy of deep tissue with large field-of-view (FOV) is critical for elucidating organization of cellular structures in plant biology. Microscopy with an implanted probe offers an effective solution. However, there exists a fundamental trade-off between the FOV and probe diameter arising from aberrations inherent in conventional imaging optics (typically, FOV < 30% of diameter). Here, we demonstrate the use of microfabricated non-imaging probes (optrodes) that when combined with a trained machine-learning algorithm is able to achieve FOV of 1x to 5x the probe diameter. Further increase in FOV is achieved by using multiple optrodes in parallel. With a 1 × 2 optrode array, we demonstrate imaging of fluorescent beads (including 30 FPS video), stained plant stem sections and stained living stems. Our demonstration lays the foundation for fast, high-resolution microscopy with large FOV in deep tissue via microfabricated non-imaging probes and advanced machine learning.
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Affiliation(s)
- Ruipeng Guo
- Department of Electrical and Computer Engineering, University of Utah, USA
| | - Reed Sorenson
- School of Biological Sciences, University of Utah, USA
| | - Robert Scharf
- Department of Electrical and Computer Engineering, University of Utah, USA
| | - Austin Koch
- Department of Electrical and Computer Engineering, University of Utah, USA
| | - Andrew Groover
- USDA Forest Service, Pacific Southwest Research Station, USA
- Department of Plant Biology, University of California Davis, USA
| | | | - Steve Blair
- Department of Electrical and Computer Engineering, University of Utah, USA
| | - Rajesh Menon
- Department of Electrical and Computer Engineering, University of Utah, USA
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Luo J, Xue N, Chen J. A Review: Research Progress of Neural Probes for Brain Research and Brain-Computer Interface. BIOSENSORS 2022; 12:bios12121167. [PMID: 36551135 PMCID: PMC9775442 DOI: 10.3390/bios12121167] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/07/2022] [Accepted: 12/13/2022] [Indexed: 06/01/2023]
Abstract
Neural probes, as an invasive physiological tool at the mesoscopic scale, can decipher the code of brain connections and communications from the cellular or even molecular level, and realize information fusion between the human body and external machines. In addition to traditional electrodes, two new types of neural probes have been developed in recent years: optoprobes based on optogenetics and magnetrodes that record neural magnetic signals. In this review, we give a comprehensive overview of these three kinds of neural probes. We firstly discuss the development of microelectrodes and strategies for their flexibility, which is mainly represented by the selection of flexible substrates and new electrode materials. Subsequently, the concept of optogenetics is introduced, followed by the review of several novel structures of optoprobes, which are divided into multifunctional optoprobes integrated with microfluidic channels, artifact-free optoprobes, three-dimensional drivable optoprobes, and flexible optoprobes. At last, we introduce the fundamental perspectives of magnetoresistive (MR) sensors and then review the research progress of magnetrodes based on it.
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Affiliation(s)
- Jiahui Luo
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ning Xue
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiamin Chen
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
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Guo B, Fan Y, Wang M, Cheng Y, Ji B, Chen Y, Wang G. Flexible Neural Probes with Electrochemical Modified Microelectrodes for Artifact-Free Optogenetic Applications. Int J Mol Sci 2021; 22:ijms222111528. [PMID: 34768957 PMCID: PMC8584107 DOI: 10.3390/ijms222111528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 11/23/2022] Open
Abstract
With the rapid increase in the use of optogenetics to investigate nervous systems, there is high demand for neural interfaces that can simultaneously perform optical stimulation and electrophysiological recording. However, high-magnitude stimulation artifacts have prevented experiments from being conducted at a desirably high temporal resolution. Here, a flexible polyimide-based neural probe with polyethylene glycol (PEG) packaged optical fiber and Pt-Black/PEDOT-GO (graphene oxide doped poly(3,4-ethylene-dioxythiophene)) modified microelectrodes was developed to reduce the stimulation artifacts that are induced by photoelectrochemical (PEC) and photovoltaic (PV) effects. The advantages of this design include quick and accurate implantation and high-resolution recording capacities. Firstly, electrochemical performance of the modified microelectrodes is significantly improved due to the large specific surface area of the GO layer. Secondly, good mechanical and electrochemical stability of the modified microelectrodes is obtained by using Pt-Black as bonding layer. Lastly, bench noise recordings revealed that PEC noise amplitude of the modified neural probes could be reduced to less than 50 µV and no PV noise was detected when compared to silicon-based neural probes. The results indicate that this device is a promising optogenetic tool for studying local neural circuits.
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Affiliation(s)
- Bangbang Guo
- Wenzhou Institute of Hangzhou Dianzi University, Wenzhou 325038, China; (B.G.); (Y.F.); (Y.C.)
- MOE Engineering Research Center of Smart Microsensors and Microsystems, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Ye Fan
- Wenzhou Institute of Hangzhou Dianzi University, Wenzhou 325038, China; (B.G.); (Y.F.); (Y.C.)
- MOE Engineering Research Center of Smart Microsensors and Microsystems, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Minghao Wang
- Wenzhou Institute of Hangzhou Dianzi University, Wenzhou 325038, China; (B.G.); (Y.F.); (Y.C.)
- MOE Engineering Research Center of Smart Microsensors and Microsystems, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou 310018, China
- Correspondence: (M.W.); (G.W.)
| | - Yuhua Cheng
- Wenzhou Institute of Hangzhou Dianzi University, Wenzhou 325038, China; (B.G.); (Y.F.); (Y.C.)
- MOE Engineering Research Center of Smart Microsensors and Microsystems, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Bowen Ji
- The Unmanned System Research Institute, Northwestern Polytechnical University, Xi’an 710060, China;
| | - Ying Chen
- The Institute of Flexible Electronics Technology of THU, Jiaxing 314000, China;
| | - Gaofeng Wang
- MOE Engineering Research Center of Smart Microsensors and Microsystems, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou 310018, China
- Correspondence: (M.W.); (G.W.)
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Ramezani Z, Seo KJ, Fang H. Hybrid Electrical and Optical Neural Interfaces. JOURNAL OF MICROMECHANICS AND MICROENGINEERING : STRUCTURES, DEVICES, AND SYSTEMS 2021; 31:044002. [PMID: 34177136 PMCID: PMC8232899 DOI: 10.1088/1361-6439/abeb30] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Neural interfaces bridge the nervous system and the outside world by recording and stimulating neurons. Combining electrical and optical modalities in a single, hybrid neural interface system could lead to complementary and powerful new ways to explore the brain. It has gained robust and exciting momentum recently in neuroscience and neural engineering research. Here, we review developments in the past several years aiming to achieve such hybrid electrical and optical microsystem platforms. Specifically, we cover three major categories of technological advances: transparent neuroelectrodes, optical neural fibers with electrodes, and neural probes/grids integrating electrodes and microscale light-emitting diodes. We discuss examples of these probes tailored to combine electrophysiological recording with optical imaging or optical neural stimulation of the brain and possible directions of future innovation.
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Affiliation(s)
| | | | - Hui Fang
- Department of Electrical and Computer Engineering
- Department of Mechanical and Industrial Engineering
- Department of Bioengineering, Northeastern University, Boston, Massachusetts 02115, USA
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Vandekerckhove B, Missinne J, Vonck K, Bauwens P, Verplancke R, Boon P, Raedt R, Vanfleteren J. Technological Challenges in the Development of Optogenetic Closed-Loop Therapy Approaches in Epilepsy and Related Network Disorders of the Brain. MICROMACHINES 2020; 12:38. [PMID: 33396287 PMCID: PMC7824489 DOI: 10.3390/mi12010038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/24/2020] [Accepted: 12/28/2020] [Indexed: 12/25/2022]
Abstract
Epilepsy is a chronic, neurological disorder affecting millions of people every year. The current available pharmacological and surgical treatments are lacking in overall efficacy and cause side-effects like cognitive impairment, depression, tremor, abnormal liver and kidney function. In recent years, the application of optogenetic implants have shown promise to target aberrant neuronal circuits in epilepsy with the advantage of both high spatial and temporal resolution and high cell-specificity, a feature that could tackle both the efficacy and side-effect problems in epilepsy treatment. Optrodes consist of electrodes to record local field potentials and an optical component to modulate neurons via activation of opsin expressed by these neurons. The goal of optogenetics in epilepsy is to interrupt seizure activity in its earliest state, providing a so-called closed-loop therapeutic intervention. The chronic implantation in vivo poses specific demands for the engineering of therapeutic optrodes. Enzymatic degradation and glial encapsulation of implants may compromise long-term recording and sufficient illumination of the opsin-expressing neural tissue. Engineering efforts for optimal optrode design have to be directed towards limitation of the foreign body reaction by reducing the implant's elastic modulus and overall size, while still providing stable long-term recording and large-area illumination, and guaranteeing successful intracerebral implantation. This paper presents an overview of the challenges and recent advances in the field of electrode design, neural-tissue illumination, and neural-probe implantation, with the goal of identifying a suitable candidate to be incorporated in a therapeutic approach for long-term treatment of epilepsy patients.
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Affiliation(s)
- Bram Vandekerckhove
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Jeroen Missinne
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Kristl Vonck
- 4Brain Team, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (K.V.); (P.B.); (R.R.)
| | - Pieter Bauwens
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Rik Verplancke
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Paul Boon
- 4Brain Team, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (K.V.); (P.B.); (R.R.)
| | - Robrecht Raedt
- 4Brain Team, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (K.V.); (P.B.); (R.R.)
| | - Jan Vanfleteren
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
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A drivable optrode for use in chronic electrophysiology and optogenetic experiments. J Neurosci Methods 2020; 348:108979. [PMID: 33096153 PMCID: PMC10174211 DOI: 10.1016/j.jneumeth.2020.108979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 09/21/2020] [Accepted: 10/13/2020] [Indexed: 11/21/2022]
Abstract
BACKGROUND Combining optogenetic tools with behaving electrophysiology is a powerful approach for investigating the neural mechanisms underlying behavior. A traditional approach to ensure viable recordings during chronic long-term electrophysiological experiments is the use of drivable electrodes. However, few options exist for drivable optrodes. NEW METHOD Here, we describe the design and construction of an economical drivable optrode for chronic experiments in behaving rodents, which allows for the simultaneous photo-stimulation and recording of distinct neuronal populations. RESULTS We demonstrate the utility of the drivable optrode by recording light-evoked modulation in awake behaving rats over multiple recording sessions and across different depths. Using a virus to drive expression of channelrhodopsin-2 (ChR2) in the anterior piriform cortex, the drivable optrode was used to record consistent light-evoked modulation of neural activity in the gustatory cortex during photo-activation of the axonal projections from anterior piriform cortex in behaving rats. COMPARISON WITH EXISTING METHODS Although sophisticated optrodes have been developed, many are expensive, unmodifiable, require advanced engineering techniques, and/or lack drivability. The drivable optrode uses relatively inexpensive materials, requires no machined parts, and can be fabricated with tools available in most labs. In addition, it can be easily modified to accommodate different experimental parameters. CONCLUSION In summary, we believe that the cost-effective and relatively simple-to-prepare design makes this drivable optrode a practical option for researchers using optogenetic and electrophysiological tools to investigate network and circuit function.
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Kim H, Brünner HS, Carlén M. The DMCdrive: practical 3D-printable micro-drive system for reliable chronic multi-tetrode recording and optogenetic application in freely behaving rodents. Sci Rep 2020; 10:11838. [PMID: 32678238 PMCID: PMC7366717 DOI: 10.1038/s41598-020-68783-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 06/30/2020] [Indexed: 11/16/2022] Open
Abstract
Electrophysiological recording and optogenetic control of neuronal activity in behaving animals have been integral to the elucidation of how neurons and circuits modulate network activity in the encoding and causation of behavior. However, most current electrophysiological methods require substantial economical investments and prior expertise. Further, the inclusion of optogenetics with electrophysiological recordings in freely moving animals adds complexity to the experimental design. Expansion of the technological repertoire across laboratories, research institutes, and countries, demands open access to high-quality devices that can be built with little prior expertise from easily accessible parts of low cost. We here present an affordable, truly easy-to-assemble micro-drive for electrophysiology in combination with optogenetics in freely moving rodents. The DMCdrive is particularly suited for reliable recordings of neurons and network activities over the course of weeks, and simplify optical tagging and manipulation of neurons in the recorded brain region. The highly functional and practical drive design has been optimized for accurate tetrode movement in brain tissue, and remarkably reduced build time. We provide a complete overview of the drive design, its assembly and use, and proof-of-principle demonstration of recordings paired with cell-type-specific optogenetic manipulations in the prefrontal cortex (PFC) of freely moving transgenic mice and rats.
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Affiliation(s)
- Hoseok Kim
- Department of Neuroscience, Karolinska Institutet, 171 65, Stockholm, Sweden.
| | - Hans Sperup Brünner
- Department of Neuroscience, Karolinska Institutet, 171 65, Stockholm, Sweden
| | - Marie Carlén
- Department of Neuroscience, Karolinska Institutet, 171 65, Stockholm, Sweden.
- Department of Biosciences and Nutrition, Karolinska Institutet, 141 83, Huddinge, Sweden.
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Patel AA, McAlinden N, Mathieson K, Sakata S. Simultaneous Electrophysiology and Fiber Photometry in Freely Behaving Mice. Front Neurosci 2020; 14:148. [PMID: 32153363 PMCID: PMC7047771 DOI: 10.3389/fnins.2020.00148] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/07/2020] [Indexed: 12/27/2022] Open
Abstract
In vivo electrophysiology is the gold standard technique used to investigate sub-second neural dynamics in freely behaving animals. However, monitoring cell-type-specific population activity is not a trivial task. Over the last decade, fiber photometry based on genetically encoded calcium indicators (GECIs) has been widely adopted as a versatile tool to monitor cell-type-specific population activity in vivo. However, this approach suffers from low temporal resolution. Here, we combine these two approaches to monitor both sub-second field potentials and cell-type-specific population activity in freely behaving mice. By developing an economical custom-made system and constructing a hybrid implant of an electrode and a fiber optic cannula, we simultaneously monitor artifact-free mesopontine field potentials and calcium transients in cholinergic neurons across the sleep-wake cycle. We find that mesopontine cholinergic activity co-occurs with sub-second pontine waves, called P-waves, during rapid eye movement sleep. Given the simplicity of our approach, simultaneous electrophysiological recording and cell-type-specific imaging provides a novel and valuable tool for interrogating state-dependent neural circuit dynamics in vivo.
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Affiliation(s)
- Amisha A Patel
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Niall McAlinden
- Department of Physics, Institute of Photonics, SUPA, University of Strathclyde, Glasgow, United Kingdom
| | - Keith Mathieson
- Department of Physics, Institute of Photonics, SUPA, University of Strathclyde, Glasgow, United Kingdom
| | - Shuzo Sakata
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
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Soltan A, Liu Y, Armstrong N, Akhter M, Corbett B, Degenaar P. Comparison between Different Optical Systems for Optogenetics based Head Mounted Device for Retina Pigmentosa. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:382-385. [PMID: 31945920 DOI: 10.1109/embc.2019.8857545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Optogenetics is a fast growing neuromodulation techniques as it can remotely stimulate neural activities of a genetically modified cells. The advantage of remotely controlling the neural activity triggered researchers to implement a headset to externally stimulate retina cells for people with retina pigmentosa. The wearable device requires an efficient optical system to focus the transmitted light pattern into the retina surface. In this work, three different lenses; contact lens, folded prism and linear lenses are used to evaluate the headset performance. A 90x90 μLED display is used as a light source and the optical efficiency for each lens is measured for different points over the lens area. Moreover, the impact of each lens on the headset performance in power and processing will be discussed in this work.
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Ahmed KK, Tamer MA, Ghareeb MM, Salem AK. Recent Advances in Polymeric Implants. AAPS PharmSciTech 2019; 20:300. [PMID: 31482251 DOI: 10.1208/s12249-019-1510-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/12/2019] [Indexed: 12/17/2022] Open
Abstract
Implantable drug delivery systems, such as drug pumps and polymeric drug depots, have emerged as means of providing predetermined drug release profiles at the desired site of action. While initial implants aimed at providing an enduring drug supply, developments in polymer chemistry and pharmaceutical technology and the growing need for refined drug delivery patterns have prompted the design of sophisticated drug delivery implants such as on-demand drug-eluting implants and personalized 3D printed implants. The types of cargo loaded into these implants range from small drug molecules to hormones and even therapeutic cells. This review will shed light upon recent advances in materials and composites used for polymeric implant fabrication, highlight select approaches employed in polymeric implant fabrication, feature medical applications where polymeric implants have a significant impact, and report recent advances made in these areas.
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