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Poulen G, Perrin FE. Advances in spinal cord injury: insights from non-human primates. Neural Regen Res 2024; 19:2354-2364. [PMID: 38526271 PMCID: PMC11090432 DOI: 10.4103/nrr.nrr-d-23-01505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/13/2023] [Accepted: 12/22/2023] [Indexed: 03/26/2024] Open
Abstract
Spinal cord injury results in significant sensorimotor deficits, currently, there is no curative treatment for the symptoms induced by spinal cord injury. Basic and pre-clinical research on spinal cord injury relies on the development and characterization of appropriate animal models. These models should replicate the symptoms observed in human, allowing for the exploration of functional deficits and investigation into various aspects of physiopathology of spinal cord injury. Non-human primates, due to their close phylogenetic association with humans, share more neuroanatomical, genetic, and physiological similarities with humans than rodents. Therefore, the responses to spinal cord injury in nonhuman primates most likely resemble the responses to traumatism in humans. In this review, we will discuss nonhuman primate models of spinal cord injury, focusing on in vivo assessments, including behavioral tests, magnetic resonance imaging, and electrical activity recordings, as well as ex vivo histological analyses. Additionally, we will present therapeutic strategies developed in non-human primates and discuss the unique specificities of non-human primate models of spinal cord injury.
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Affiliation(s)
- Gaetan Poulen
- University of Montpellier, INSERM, EPHE, Montpellier, France
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
| | - Florence E. Perrin
- University of Montpellier, INSERM, EPHE, Montpellier, France
- Institut Universitaire de France (IUF), Paris, France
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Liu Z, Lai J, Kong D, Zhao Y, Zhao J, Dai J, Zhang M. Advances in electroactive bioscaffolds for repairing spinal cord injury. Biomed Mater 2024; 19:032005. [PMID: 38636508 DOI: 10.1088/1748-605x/ad4079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Accepted: 04/18/2024] [Indexed: 04/20/2024]
Abstract
Spinal cord injury (SCI) is a devastating neurological disorder, leading to loss of motor or somatosensory function, which is the most challenging worldwide medical problem. Re-establishment of intact neural circuits is the basis of spinal cord regeneration. Considering the crucial role of electrical signals in the nervous system, electroactive bioscaffolds have been widely developed for SCI repair. They can produce conductive pathways and a pro-regenerative microenvironment at the lesion site similar to that of the natural spinal cord, leading to neuronal regeneration and axonal growth, and functionally reactivating the damaged neural circuits. In this review, we first demonstrate the pathophysiological characteristics induced by SCI. Then, the crucial role of electrical signals in SCI repair is introduced. Based on a comprehensive analysis of these characteristics, recent advances in the electroactive bioscaffolds for SCI repair are summarized, focusing on both the conductive bioscaffolds and piezoelectric bioscaffolds, used independently or in combination with external electronic stimulation. Finally, thoughts on challenges and opportunities that may shape the future of bioscaffolds in SCI repair are concluded.
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Affiliation(s)
- Zeqi Liu
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Jiahui Lai
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Dexin Kong
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Yannan Zhao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Jiakang Zhao
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Jianwu Dai
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Mingming Zhang
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
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Jimenez C, Sparrey CJ, Narimani M. Identification of injured elements in computational models of spinal cord injury using machine learning . ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023; 2023:1-4. [PMID: 38082848 DOI: 10.1109/embc40787.2023.10340243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
The purpose of this study was to use machine learning (ML) algorithms to identify tissue damage based on the mechanical outputs of computational models of spinal cord injury (SCI). Three datasets corresponding to gray matter, white matter, and the combination of gray and white matter tissues were used to train the models. These datasets were built from the comparison of histological images taken from SCI experiments in non-human primates and corresponding subject-specific finite element (FE) models. Four ML algorithms were evaluated and compared using cross-validation and the area under the receiver operating characteristic curve (AUC). After hyperparameter tuning, the AUC mean values for the algorithms ranged between 0.79 and 0.82, with a standard deviation no greater than 0.02. The findings of this study also showed that k-nearest neighbors and logistic regression algorithms were better at identifying injured elements than support vector machines and decision trees. Additionally, depending on the evaluated dataset, the mean values of other performance metrics, such as precision and recall, varied between algorithms. These initial results suggest that different algorithms might be more sensitive to the skewed distribution of classes in the studied datasets, and that identifying damage independently or simultaneously in the gray and white matter tissues might require a better definition of relevant features and the use of different ML algorithms. These approaches will contribute to improving the current understanding of the relationship between mechanical loading and tissue damage during SCI and will have implications for the development of prevention strategies for this condition.Clinical Relevance- Linking FE model predictions of mechanical loading to tissue damage is an essential step for FE models to provide clinically relevant information. Combined with imaging technologies, these models can provide useful insights to predict the extent of damage in animal subjects and guide the decision-making process during treatment planning.
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Obaid N, Morioka K, Sinopoulou E, Nout-Lomas YS, Salegio E, Bresnahan JC, Beattie MS, Sparrey CJ. The biomechanical implications of neck position in cervical contusion animal models of SCI. Front Neurol 2023; 14:1152472. [PMID: 37346165 PMCID: PMC10280737 DOI: 10.3389/fneur.2023.1152472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 05/17/2023] [Indexed: 06/23/2023] Open
Abstract
Large animal contusion models of spinal cord injury are an essential precursor to developing and evaluating treatment options for human spinal cord injury. Reducing variability in these experiments has been a recent focus as it increases the sensitivity with which treatment effects can be detected while simultaneously decreasing the number of animals required in a study. Here, we conducted a detailed review to explore if head and neck positioning in a cervical contusion model of spinal cord injury could be a factor impacting the biomechanics of a spinal cord injury, and thus, the resulting outcomes. By reviewing existing literature, we found evidence that animal head/neck positioning affects the exposed level of the spinal cord, morphology of the spinal cord, tissue mechanics and as a result the biomechanics of a cervical spinal cord injury. We posited that neck position could be a hidden factor contributing to variability. Our results indicate that neck positioning is an important factor in studying biomechanics, and that reporting these values can improve inter-study consistency and comparability and that further work needs to be done to standardize positioning for cervical spinal cord contusion injury models.
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Affiliation(s)
- Numaira Obaid
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, BC, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, BC, Canada
| | - Kazuhito Morioka
- Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, CA, United States
- Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Eleni Sinopoulou
- Center for Neural Repair, University of California, San Diego, San Diego, CA, United States
| | - Yvette S. Nout-Lomas
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO, United States
| | | | - Jacqueline C. Bresnahan
- Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Michael S. Beattie
- Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Carolyn J. Sparrey
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, BC, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, BC, Canada
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Bennet BM, Pardo ID, Assaf BT, Buza E, Cramer S, Crawford LK, Engelhardt JA, Grubor B, Morrison JP, Osborne TS, Sharma AK, Bolon B. Scientific and Regulatory Policy Committee Points to Consider: Sampling, Processing, Evaluation, Interpretation, and Reporting of Test Article-Related Ganglion Pathology for Nonclinical Toxicity Studies. Toxicol Pathol 2023; 51:176-204. [PMID: 37489508 DOI: 10.1177/01926233231179707] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
Certain biopharmaceutical products consistently affect dorsal root ganglia, trigeminal ganglia, and/or autonomic ganglia. Product classes targeting ganglia include antineoplastic chemotherapeutics, adeno-associated virus-based gene therapies, antisense oligonucleotides, and anti-nerve growth factor agents. This article outlines "points to consider" for sample collection, processing, evaluation, interpretation, and reporting of ganglion findings; these points are consistent with published best practices for peripheral nervous system evaluation in nonclinical toxicity studies. Ganglion findings often occur as a combination of neuronal injury (e.g., degeneration, necrosis, and/or loss) and/or glial effects (e.g., increased satellite glial cell cellularity) with leukocyte accumulation (e.g., mononuclear cell infiltration or inflammation). Nerve fiber degeneration and/or glial reactions may be seen in nerves, dorsal spinal nerve roots, spinal cord, and occasionally brainstem. Interpretation of test article (TA)-associated effects may be confounded by incidental background changes or experimental procedure-related changes and limited historical control data. Reports should describe findings at these sites, any TA relationship, and the criteria used for assigning severity grades. Contextualizing adversity of ganglia findings can require a weight-of-evidence approach because morphologic changes of variable severity occur in ganglia but often are not accompanied by observable overt in-life functional alterations detectable by conventional behavioral and neurological testing techniques.
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Affiliation(s)
| | | | | | - Elizabeth Buza
- University of Pennsylvania, Gene Therapy Program, Philadelphia, Pennsylvania, USA
| | | | - LaTasha K Crawford
- University of Wisconsin-Madison, School of Veterinary Medicine, Madison, Wisconsin, USA
| | | | | | - James P Morrison
- Charles River Laboratories, Inc., Shrewsbury, Massachusetts, USA
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Obaid N, Bojic AM, Jannesar S, Salegio E, Nout-Lomas Y, Beattie M, Bresnahan J, Sparrey C. Effect of Impact Parameters on a Unilateral Contusion Model of Spinal Cord Injury in a Virtual Population of Non-Human Primates. Neurotrauma Rep 2023; 4:367-374. [PMID: 37350793 PMCID: PMC10282973 DOI: 10.1089/neur.2023.0006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/24/2023] Open
Abstract
Non-human primate (NHP) spinal cord injury experiments exhibit high intersubject variability in biomechanical parameters even when a consistent impact protocol is applied to each subject. Optimizing impact parameters to reduce this variability through experiments is logistically challenging in NHP studies. Finite element models provide a complimentary tool to inform experimental design without the cost and complexity of live animal studies. A morphologically variable virtual population (N = 10) of NHPs quantified the interaction of morphological variability and different impact conditions in a unilateral cervical contusion, including impactor size (4 and 5 mm) and mediolateral alignment over the cord midline (0.5 and 1 mm). We explored the effect of these conditions on the magnitude and intersubject variability of impact force and cord lateral slippage. The study demonstrated that a 1-mm mediolateral alignment maximized peak forces and minimized lateral slippage. A 5-mm impactor was beneficial in increasing peak forces, whereas a 4-mm impactor reduced lateral slippage. Comparatively, intersubject variability in peak forces and lateral slippage were minimized with a 0.5-mm mediolateral alignment. The study highlights that impact parameters selected based on peak forces may not be beneficial in reducing variability. The study also showed that morphology was an important contributor to variability. Integrating morphology variability through a virtual population in an injury simulation to investigate mechanistic research questions will more effectively capture the heterogeneity of experiments and provide better insights for effective experimental design.
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Affiliation(s)
- Numaira Obaid
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
| | - Ana-Maria Bojic
- Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Shervin Jannesar
- School of Engineering Science, Simon Fraser University, Burnaby, British Columbia, Canada
| | | | - Yvette Nout-Lomas
- Department of Clinical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Michael Beattie
- Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, California, USA
| | - Jacqueline Bresnahan
- Brain and Spinal Injury Center, Department of Neurological Surgery, University of California, San Francisco, California, USA
| | - Carolyn Sparrey
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
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7
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Current Advancements in Spinal Cord Injury Research—Glial Scar Formation and Neural Regeneration. Cells 2023; 12:cells12060853. [PMID: 36980193 PMCID: PMC10046908 DOI: 10.3390/cells12060853] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
Spinal cord injury (SCI) is a complex tissue injury resulting in permanent and degenerating damage to the central nervous system (CNS). Detrimental cellular processes occur after SCI, including axonal degeneration, neuronal loss, neuroinflammation, reactive gliosis, and scar formation. The glial scar border forms to segregate the neural lesion and isolate spreading inflammation, reactive oxygen species, and excitotoxicity at the injury epicenter to preserve surrounding healthy tissue. The scar border is a physicochemical barrier composed of elongated astrocytes, fibroblasts, and microglia secreting chondroitin sulfate proteoglycans, collogen, and the dense extra-cellular matrix. While this physiological response preserves viable neural tissue, it is also detrimental to regeneration. To overcome negative outcomes associated with scar formation, therapeutic strategies have been developed: the prevention of scar formation, the resolution of the developed scar, cell transplantation into the lesion, and endogenous cell reprogramming. This review focuses on cellular/molecular aspects of glial scar formation, and discusses advantages and disadvantages of strategies to promote regeneration after SCI.
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Gayen CD, Bessen MA, Dorrian RM, Quarrington RD, Mulaibrahimovic A, Doig RLO, Freeman BJC, Leonard AV, Jones CF. A survival model of thoracic contusion spinal cord injury in the domestic pig. J Neurotrauma 2022; 40:965-980. [PMID: 36200622 DOI: 10.1089/neu.2022.0281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Spinal cord injury (SCI) frequently results in motor, sensory and autonomic dysfunction for which there is currently no cure. Recent preclinical and clinical research has led to promising advances in treatment; however, therapeutics indicating promise in rodents have not translated successfully in human trials, likely due, in part, to gross anatomical and physiological differences between the species. Therefore, large animal models of SCI may facilitate the study of secondary injury processes that are influenced by scale, and assist the translation of potential therapeutic interventions. The aim of this study was to characterize two severities of thoracic contusion SCI in female domestic pigs, measuring motor function and spinal cord lesion characteristics, over two weeks post-SCI. A custom instrumented weight drop injury device was used to release a 50 g impactor from 10 cm (n=3) or 20 cm (n=7) onto the exposed dura, to induce a contusion at the T10 thoracic spinal level. Hind limb motor function was assessed at 8 and 13 days post-SCI using a 10-point scale. Volume and extent of lesion-associated signal hyperintensity in T2-weighted magnetic resonance (MR) images was assessed at 3, 7 and 14 days post-injury. Animals were transcardially perfused at 14 days post-SCI and spinal cord tissue was harvested for histological analysis. Bowel function was retained in all animals and transient urinary retention occurred in two animals after catheter removal. All animals displayed hind limb motor deficits. Animals in the 10 cm group demonstrated some stepping and weight bearing and scored a median 2-3 points higher on the 10-point motor function scale at 8 and 13 days post-SCI, than the 20 cm group. Histological lesion volume was 20 % greater, and 30 % less white matter was spared, in the 20 cm group than in the 10 cm group. The MR signal hyperintensity in the 20 cm injury group had a median cranial-caudal extent approximately 1.5 times greater than the 10 cm injury group at all three time points, and median volumes 1.8, 2.5 and 4.5 times greater at day 3, 7 and 14 post-injury, respectively. Regional differences in axonal injury were observed between groups, with amyloid precursor protein immunoreactivity greatest in the 20 cm group in spinal cord sections adjacent the injury epicenter. This study demonstrated graded injuries in a domestic pig strain, with outcome measures comparable to miniature pig models of contusion SCI. The model provides a vehicle for the study of SCI and potential treatments, particularly where miniature pig strains are not available and/or where small animal models are not appropriate for the research question.
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Affiliation(s)
- Christine D Gayen
- Translational Neuropathology Laboratory, School of Biomedicine, The University of Adelaide, Adelaide, South Australia, Australia
- Adelaide Spinal Research Group, Centre for Orthopaedics and Trauma Research, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Madeleine A Bessen
- Adelaide Spinal Research Group, Centre for Orthopaedics and Trauma Research, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Ryan M Dorrian
- Translational Neuropathology Laboratory, School of Biomedicine, The University of Adelaide, Adelaide, South Australia, Australia
| | - Ryan D Quarrington
- Adelaide Spinal Research Group, Centre for Orthopaedics and Trauma Research, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Adnan Mulaibrahimovic
- Adelaide Spinal Research Group, Centre for Orthopaedics and Trauma Research, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Ryan L O'Hare Doig
- Neil Sachse Centre for Spinal Cord Research, Lifelong Health Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
| | - Brian J C Freeman
- Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
- Royal Adelaide Hospital, Adelaide South Australia, Australia
| | - Anna V Leonard
- Translational Neuropathology Laboratory, School of Biomedicine, The University of Adelaide, Adelaide, South Australia, Australia
| | - Claire F Jones
- Adelaide Spinal Research Group, Centre for Orthopaedics and Trauma Research, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
- School of Mechanical Engineering, The University of Adelaide, Adelaide, South Australia, Australia
- Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, South Australia, Australia
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Yang J, Okyere SK, Zheng J, Cao B, Hu Y. Seasonal Prevalence of Gastrointestinal Parasites in Macaques ( Macaca thibetana) at Mount Emei Scenic Area in China. Animals (Basel) 2022; 12:1816. [PMID: 35883363 PMCID: PMC9311871 DOI: 10.3390/ani12141816] [Citation(s) in RCA: 4] [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: 06/29/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 11/18/2022] Open
Abstract
The aim of the study was to elucidate the prevalence of intestinal parasites in macaques at the Mt. Emei Scenic Area of Sichuan, China. A total of 168 fecal samples were collected from yellow (n = 31), black (n = 19), new (n = 57), Leidongping (n = 57) and Wuxiangang (n = 4) macaques from 2019 to 2020. The fecal samples were tested for various gastrointestinal parasites following the microscopic detection method. The results showed that the total prevalence rate of the intestinal parasite was 51.19% (86/168), whereas the intestinal parasite with the highest prevalence was Gongylonema spp. (26.79%) for helminth and Entamoeba spp. (18.45%) for protozoa. Interestingly, the highest prevalence of intestinal parasites was observed during the summer season (86.21%), and the lowest was observed during the winter season (7.14%). There was a positive correlation observed between the human contact frequency and total prevalence rate of the intestinal parasites (p < 0.05); however, there was no correlation between the human contact frequency and total prevalence of the intestinal parasites at different seasons (p > 0.05). In conclusion, the dominant parasites Gongylonema spp. and Entamoeba spp. cause various diseases that may be transmitted to humans and other animals; therefore, there is a need for a proper management system, such as parasite control measures and population protection in the Mt. Emei Scenic Area of Sichuan, China.
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Affiliation(s)
- Jiandong Yang
- College of Animal Sciences and Technology, Sichuan Agricultural University, Chengdu 611130, China;
| | - Samuel Kumi Okyere
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (S.K.O.); (B.C.)
| | - Jie Zheng
- Forestry Management Agency of Mount Meishan, Meishan 614200, China;
| | - Buyuan Cao
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (S.K.O.); (B.C.)
| | - Yanchun Hu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (S.K.O.); (B.C.)
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Rycman A, McLachlin S, Cronin DS. Comparison of numerical methods for cerebrospinal fluid representation and fluid-structure interaction during transverse impact of a finite element spinal cord model. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2022; 38:e3570. [PMID: 34997836 DOI: 10.1002/cnm.3570] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/04/2022] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Spinal cord impacts can have devastating consequences. Computational models can investigate such impacts but require biofidelic numerical representations of the neural tissues and fluid-structure interaction with cerebrospinal fluid. Achieving this biofidelity is challenging, particularly for efficient implementation of the cerebrospinal fluid in full computational human body models. The goal of this study was to assess the biofidelity and computational efficiency of fluid-structure interaction methods representing the cerebrospinal fluid interacting with the spinal cord, dura, and pia mater using experimental pellet impact test data from bovine spinal cords. Building on an existing finite element model of the spinal cord and pia mater, an orthotropic hyperelastic constitutive model was proposed for the dura mater and fit to literature data. The dura mater and cerebrospinal fluid were integrated with the existing finite element model to assess four fluid-structure interaction methods under transverse impact: Lagrange, pressurized volume, smoothed particle hydrodynamics, and arbitrary Lagrangian-Eulerian. The Lagrange method resulted in an overly stiff mechanical response, whereas the pressurized volume method over-predicted compression of the neural tissues. Both the smoothed particle hydrodynamics and arbitrary Lagrangian-Eulerian methods were able to effectively model the impact response of the pellet on the dura mater, outflow of the cerebrospinal fluid, and compression of the spinal cord; however, the arbitrary Lagrangian-Eulerian compute time was approximately five times higher than smoothed particle hydrodynamics. Crucial to implementation in human body models, the smoothed particle hydrodynamics method provided a computationally efficient and representative approach to model spinal cord fluid-structure interaction during transverse impact.
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Affiliation(s)
- Aleksander Rycman
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Stewart McLachlin
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Duane S Cronin
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, Canada
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11
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Anatomical and behavioral outcomes following a graded hemi-contusive cervical spinal cord injury model in mice. Behav Brain Res 2022; 419:113698. [PMID: 34856301 DOI: 10.1016/j.bbr.2021.113698] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 11/20/2021] [Accepted: 11/26/2021] [Indexed: 12/29/2022]
Abstract
BACKGROUND A graded hemi-contusion spinal cord injury produces complex anatomical deformation of the spinal cord parenchyma. The relationship between lesion severity and behavioral consequences in a novel contusion mouse model remains unknown. PURPOSE We aimed to establish a graded cervical hemi-contusion spinal cord injury model in mice and investigate the correlation between graded anatomical damage to the spinal cord and resulting behavioral impairments. METHODS Thirty-two mice were divided into groups of 1.2 mm, 1.5 mm and sham. The tip of an impactor with a diameter of 1 mm was utilized to compress the left dorsal cord of C5 by 1.2 mm or 1.5 mm at a speed of 300 mm/s. Forelimb motor function was evaluated using rearing, grooming and grip-strength tests before and after the injuries. Histologically the area of white matter sparing, gray matter sparing and lesion area were quantified at 6-week-post-injury. RESULTS Behavioral assessments showed a more severe forelimb functional deficit in 1.5 mm contusion displacements relative to 1.2 mm contusion displacements after injury. The 1.2 mm hemi-contusion mainly caused damage to the dorsal fasciculus, ventral and dorsal horn, while the 1.5 mm hemi-contusion lead to additional damage extending to ventral fasciculus. Sparing of the gray and white matter at the epicenter was 36.8 ± 2.4% and 12.4 ± 2.6% in the 1.2 mm group, and 27.6 ± 4.0% and 4.1 ± 2.2% in the 1.5 mm group, respectively. Furthermore, the lesion area was 20.8 ± 3.0% and 36.0 ± 2.1% in the 1.2 mm and 1.5 mm groups, respectively. There was a significant correlation between the performance in the grooming test and white matter sparing, and between grip-test strength and gray matter sparing. CONCLUSION The present study demonstrates that a hemi-contusion cervical spinal cord injury in mice can be graded by contusion displacement and that there is a correlation between anatomical and behavioral outcomes. This study provides a means for determining the severity of lesions in a contusion mouse model.
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Züchner M, Escalona MJ, Teige LH, Balafas E, Zhang L, Kostomitsopoulos N, Boulland JL. How to generate graded spinal cord injuries in swine - tools and procedures. Dis Model Mech 2021; 14:dmm049053. [PMID: 34464444 PMCID: PMC8419714 DOI: 10.1242/dmm.049053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 07/07/2021] [Indexed: 12/13/2022] Open
Abstract
Spinal cord injury (SCI) is a medically, psychologically and socially disabling condition. A large body of our knowledge on the basic mechanisms of SCI has been gathered in rodents. For preclinical validation of promising therapies, the use of animal models that are closer to humans has several advantages. This has promoted the more-intensive development of large-animal models for SCI during the past decade. We recently developed a multimodal SCI apparatus for large animals that generated biomechanically reproducible impacts in vivo. It is composed of a spring-load impactor and support systems for the spinal cord and the vertebral column. We now present the functional outcome of farm pigs and minipigs injured with different lesion strengths. There was a correlation between the biomechanical characteristics of the impact, the functional outcome and the tissue damage observed several weeks after injury. We also provide a detailed description of the procedure to generate such a SCI in both farm pigs and minipigs, in the hope to ease the adoption of the swine model by other research groups.
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Affiliation(s)
- Mark Züchner
- Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
| | - Manuel J. Escalona
- Department for Immunology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
| | - Lena Hammerlund Teige
- Department for Immunology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
| | - Evangelos Balafas
- Center of Clinical Experimental Surgery and Translational Research, Biomedical Research Foundation of Academy of Athens, 11527 Athens, Greece
| | - Lili Zhang
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, 0450 Oslo, Norway
| | - Nikolaos Kostomitsopoulos
- Center of Clinical Experimental Surgery and Translational Research, Biomedical Research Foundation of Academy of Athens, 11527 Athens, Greece
| | - Jean-Luc Boulland
- Department for Immunology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
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13
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Cerro PD, Barriga-Martín A, Vara H, Romero-Muñoz LM, Rodríguez-De-Lope Á, Collazos-Castro JE. Neuropathological and Motor Impairments after Incomplete Cervical Spinal Cord Injury in Pigs. J Neurotrauma 2021; 38:2956-2977. [PMID: 34121450 DOI: 10.1089/neu.2020.7587] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Humans, primates, and rodents with cervical spinal cord injury (SCI) show permanent sensorimotor dysfunction of the upper/forelimb as consequence of axonal damage and local neuronal death. This work aimed at characterizing a model of cervical SCI in domestic pigs in which hemisection with excision of 1 cm of spinal cord was performed to reproduce the loss of neural tissue observed in human neuropathology. Posture and motor control were assessed over 3 months by scales and kinematics of treadmill locomotion. Histological measurements included lesion length, atrophy of the adjacent spinal cord segments, and neuronal death. In some animals, the retrograde neural tracer aminostilbamidine was injected in segments caudal to the lesion to visualize propriospinal projection neurons. Neuronal loss extended for 4-6 mm from the lesion borders and was more severe in the ipsilateral, caudal spinal cord stump. Axonal Wallerian degeneration was observed caudally and rostrally, associated with marked atrophy of the white matter in the spinal cord segments adjacent to the lesion. The pigs showed chronic monoplegia or severe monoparesis of the foreleg ipsilateral to the lesion, whereas the trunk and the other legs had postural and motor impairments that substantially improved during the first month post-lesion. Adaptations of the walking cycle such as those reported for rats and humans ameliorated the negative impact of focal neurological deficits on locomotor performance. These results provide a baseline of behavior and histology in a porcine model of cervical spinal cord hemisection that can be used for translational research in SCI therapeutics.
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Affiliation(s)
- Patricia Del Cerro
- Neural Repair Laboratory, Hospital Nacional de Parapléjicos, Toledo, Spain.,Program in Neuroscience, Autonoma de Madrid University, Madrid, Spain
| | - Andrés Barriga-Martín
- Orthopedic Surgery and Traumatology, Hospital Nacional de Parapléjicos, Toledo, Spain
| | - Hugo Vara
- Neural Repair Laboratory, Hospital Nacional de Parapléjicos, Toledo, Spain
| | - Luis M Romero-Muñoz
- Orthopedic Surgery and Traumatology, Hospital Nacional de Parapléjicos, Toledo, Spain
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14
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Wu X, Xu X, Liu Q, Ding J, Liu J, Huang Z, Huang Z, Wu X, Li R, Yang Z, Jiang H, Liu J, Zhu Q. Unilateral cervical spinal cord injury induces bone loss and metabolic changes in non-human primates ( Macaca fascicularis). J Orthop Translat 2021; 29:113-122. [PMID: 34178602 PMCID: PMC8193057 DOI: 10.1016/j.jot.2021.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 11/14/2020] [Accepted: 03/01/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND/OBJECTIVE The deleterious effects of chronic spinal cord injury (SCI) on the skeleton in rats, especially the lower extremities, has been proved previously. However, the long-term skeletal changes after SCI in non-human primates (NHP) have been scarcely studied. This study aimed to evaluate the bone loss in limbs and vertebrae and the bone metabolic changes in NHP after unilateral cervical spinal cord contusion injury. METHODS Twelve Macaca fascicularis were randomly divided into the SCI (n=8) and the Sham (n=4) groups. The SCI models were established using hemi-contusion cervical spinal cord injury on fifth cervical vertebra (C5), and were further evaluated by histological staining and neurophysiological monitoring. Changes of bone microstructures, bone biomechanics, and bone metabolism markers were assessed by micro-CT, micro-FEA and serological kit. RESULTS The NHP hemi-contusion cervical SCI model led to consistent unilateral limb dysfunction and potential plasticity in the face of loss of spinal cord. Furthermore, the cancellous bone mass of ipsilateral humerus and radius decreased significantly compared to the contralateral side. The bone volume fraction of humerus and radius were 17.2% and 20.1% on the ipsilateral while 29.0% and 30.1% on the contralateral respectively. Similarly, the thickness of the cortical bone in the ipsilateral forelimbs was significantly decreased, as well as the bone strength of the ipsilateral forelimbs. These changes were accompanied by diminished concentration of osteocalcin and total procollagen type 1 N-terminal propeptide (t-P1NP) as well as increased level of β-C-terminal cross-linking telopeptide of type 1collagen (β-CTX) in serological testing. CONCLUSIONS The present study demonstrated that hemi-SCI induced loss of bone mass and compromised biomechanical performance in ipsilateral forelimbs, which could be indicated by both muscle atrophy and serological changes of bone metabolism, and associated with a consistent loss of large-diameter cells of sensory neurons in the dorsal root ganglia. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE Our study, for the first time, demonstrated the bone loss in limbs and vertebrae as well as the bone metabolic changes in non-human primates after unilateral spinal cord injury (SCI). This may help to elucidate the role of muscle atrophy, serological changes and loss of sensory neurons in the mechanisms of SCI-induced osteoporosis, which would be definitely better compared with rodent models.
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Affiliation(s)
- Xiuhua Wu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiaolin Xu
- Department of Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Qi Liu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Jianyang Ding
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Junhao Liu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhiping Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zucheng Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiaoliang Wu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Rong Li
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhou Yang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Hui Jiang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Jie Liu
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, Vancouver, BritishColumbia, Canada
| | - Qingan Zhu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
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15
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Aarabi B, Akhtar-Danesh N, Simard JM, Chryssikos T, Shanmuganathan K, Olexa J, Sansur CA, Crandall KM, Wessell AP, Cannarsa G, Sharma A, Lomangino CD, Boulter J, Scarboro M, Oliver J, Ahmed AK, Wenger N, Serra R, Shea P, Schwartzbauer GT. Efficacy of Early (≤ 24 Hours), Late (25-72 Hours), and Delayed (>72 Hours) Surgery with Magnetic Resonance Imaging-Confirmed Decompression in American Spinal Injury Association Impairment Scale Grades C and D Acute Traumatic Central Cord Syndrome Caused by Spinal Stenosis. J Neurotrauma 2021; 38:2073-2083. [PMID: 33726507 PMCID: PMC8309437 DOI: 10.1089/neu.2021.0040] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The therapeutic significance of timing of decompression in acute traumatic central cord syndrome (ATCCS) caused by spinal stenosis remains unsettled. We retrospectively examined a homogenous cohort of patients with ATCCS and magnetic resonance imaging (MRI) evidence of post-treatment spinal cord decompression to determine whether timing of decompression played a significant role in American Spinal Injury Association (ASIA) motor score (AMS) 6 months following trauma. We used the t test, analysis of variance, Pearson correlation coefficient, and multiple regression for statistical analysis. During a 19-year period, 101 patients with ATCCS, admission ASIA Impairment Scale (AIS) grades C and D, and an admission AMS of ≤95 were surgically decompressed. Twenty-four of 101 patients had an AIS grade C injury. Eighty-two patients were males, the mean age of patients was 57.9 years, and 69 patients had had a fall. AMS at admission was 68.3 (standard deviation [SD] 23.4); upper extremities (UE) 28.6 (SD 14.7), and lower extremities (LE) 41.0 (SD 12.7). AMS at the latest follow-up was 93.1 (SD 12.8), UE 45.4 (SD 7.6), and LE 47.9 (SD 6.6). Mean number of stenotic segments was 2.8, mean canal compromise was 38.6% (SD 8.7%), and mean intramedullary lesion length (IMLL) was 23 mm (SD 11). Thirty-six of 101 patients had decompression within 24 h, 38 patients had decompression between 25 and 72 h, and 27 patients had decompression >72 h after injury. Demographics, etiology, AMS, AIS grade, morphometry, lesion length, surgical technique, steroid protocol, and follow-up AMS were not statistically different between groups treated at different times. We analyzed the effect size of timing of decompression categorically and in a continuous fashion. There was no significant effect of the timing of decompression on follow-up AMS. Only AMS at admission determined AMS at follow-up (coefficient = 0.31; 95% confidence interval [CI]:0.21; p = 0.001). We conclude that timing of decompression in ATCCS caused by spinal stenosis has little bearing on ultimate AMS at follow-up.
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Affiliation(s)
- Bizhan Aarabi
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA.,R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Noori Akhtar-Danesh
- School of Nursing and Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada
| | - J Marc Simard
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Timothy Chryssikos
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Joshua Olexa
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Charles A Sansur
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Kenneth M Crandall
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Aaron P Wessell
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gregory Cannarsa
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ashish Sharma
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Cara D Lomangino
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jason Boulter
- Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Maureen Scarboro
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jeffrey Oliver
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Abdul Kareem Ahmed
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Nicole Wenger
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Riccardo Serra
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Phelan Shea
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gary T Schwartzbauer
- Department of Neurosurgery and University of Maryland School of Medicine, Baltimore, Maryland, USA.,R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
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16
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Mummaneni N, Burke JF, DiGiorgio AM, Thomas LH, Duong-Fernandez X, Harris M, Pascual LU, Ferguson AR, Russell Huie J, Pan JZ, Hemmerle DD, Singh V, Torres-Espin A, Omondi C, Kyritsis N, Weinstein PR, Whetstone WD, Manley GT, Bresnahan JC, Beattie MS, Cohen-Adad J, Dhall SS, Talbott JF. Injury volume extracted from MRI predicts neurologic outcome in acute spinal cord injury: A prospective TRACK-SCI pilot study. J Clin Neurosci 2020; 82:231-236. [PMID: 33248950 DOI: 10.1016/j.jocn.2020.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/01/2020] [Indexed: 12/18/2022]
Abstract
Conventional MRI measures of traumatic spinal cord injury severity largely rely on 2-dimensional injury characteristics such as intramedullary lesion length and cord compression. Recent advances in spinal cord (SC) analysis have led to the development of a robust anatomic atlas incorporated into an open-source platform called the Spinal Cord Toolbox (SCT) that allows for quantitative volumetric injury analysis. In the current study, we evaluate the prognostic value of volumetric measures of spinal cord injury on MRI following registration of T2-weighted (T2w) images and segmented lesions from acute SCI patients with a standardized atlas. This IRB-approved prospective cohort study involved the image analysis of 60 blunt cervical SCI patients enrolled in the TRACK-SCI clinical research protocol. Axial T2w MRI data obtained within 24 h of injury were processed using the SCT. Briefly, SC MRIs were automatically segmented using the sct_deepseg_sc tool in the SCT and segmentations were manually corrected by a neuro-radiologist. Lesion volume data were used as predictor variables for correlation with lower extremity motor scores at discharge. Volumetric MRI measures of T2w signal abnormality comprising the SCI lesion accurately predict lower extremity motor scores at time of patient discharge. Similarly, MRI measures of injury volume significantly correlated with motor scores to a greater degree than conventional 2-D metrics of lesion size. The volume of total injury and of injured spinal cord motor regions on T2w MRI is significantly and independently associated with neurologic outcome at discharge after injury.
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Affiliation(s)
- Nikhil Mummaneni
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA
| | - John F Burke
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA.
| | - Anthony M DiGiorgio
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Leigh H Thomas
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Xuan Duong-Fernandez
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Mark Harris
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Lisa U Pascual
- Orthopedic Trauma Institute, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Orthopedic Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Adam R Ferguson
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA; San Francisco Veterans Affairs Healthcare System, San Francisco, CA, USA
| | - J Russell Huie
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Jonathan Z Pan
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, CA, USA
| | - Debra D Hemmerle
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Vineeta Singh
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA; Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Abel Torres-Espin
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Cleopa Omondi
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Nikos Kyritsis
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Phillip R Weinstein
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA; Institute for Neurodegenerative Diseases, Spine Center, University of California San Francisco, San Francisco, CA, USA
| | - William D Whetstone
- Department of Emergency Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Geoffrey T Manley
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Jacqueline C Bresnahan
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Michael S Beattie
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA; Weill Institutes for Neuroscience, San Francisco, CA, USA
| | - Julien Cohen-Adad
- Polytechnique Montréal, Université de Montréal, Montréal, Quebec, Canada
| | - Sanjay S Dhall
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Jason F Talbott
- Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA; Department of Radiology and Biomedical Imaging, Zuckerberg San Francisco General Hospital, San Francisco, CA, USA
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17
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Jannesar S, Salegio EA, Beattie MS, Bresnahan JC, Sparrey CJ. Correlating Tissue Mechanics and Spinal Cord Injury: Patient-Specific Finite Element Models of Unilateral Cervical Contusion Spinal Cord Injury in Non-Human Primates. J Neurotrauma 2020; 38:698-717. [PMID: 33066716 DOI: 10.1089/neu.2019.6840] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Non-human primate (NHP) models are the closest approximation of human spinal cord injury (SCI) available for pre-clinical trials. The NHP models, however, include broader morphological variability that can confound experimental outcomes. We developed subject-specific finite element (FE) models to quantify the relationship between impact mechanics and SCI, including the correlations between FE outcomes and tissue damage. Subject-specific models of cervical unilateral contusion SCI were generated from pre-injury MRIs of six NHPs. Stress and strain outcomes were compared with lesion histology using logit analysis. A parallel generic model was constructed to compare the outcomes of subject-specific and generic models. The FE outcomes were correlated more strongly with gray matter damage (0.29 < R2 < 0.76) than white matter (0.18 < R2 < 0.58). Maximum/minimum principal strain, Von-Mises and Tresca stresses showed the strongest correlations (0.31 < R2 < 0.76) with tissue damage in the gray matter while minimum principal strain, Von-Mises stress, and Tresca stress best predicted white matter damage (0.23 < R2 < 0.58). Tissue damage thresholds varied for each subject. The generic FE model captured the impact biomechanics in two of the four models; however, the correlations between FE outcomes and tissue damage were weaker than the subject-specific models (gray matter [0.25 < R2 < 0.69] and white matter [R2 < 0.06] except for one subject [0.26 < R2 < 0.48]). The FE mechanical outputs correlated with tissue damage in spinal cord white and gray matters, and the subject-specific models accurately mimicked the biomechanics of NHP cervical contusion impacts.
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Affiliation(s)
- Shervin Jannesar
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada.,International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
| | - Ernesto A Salegio
- Brain and Spinal Injury Center, University of California San Francisco, San Francisco, California, USA
| | - Michael S Beattie
- Brain and Spinal Injury Center, University of California San Francisco, San Francisco, California, USA
| | - Jacqueline C Bresnahan
- Brain and Spinal Injury Center, University of California San Francisco, San Francisco, California, USA
| | - Carolyn J Sparrey
- Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia, Canada.,International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
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18
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Liu J, Yang Z, Wu X, Huang Z, Huang Z, Chen X, Liu Q, Jiang H, Zhu Q. Comparison of the anatomical morphology of cervical vertebrae between humans and macaques: related to a spinal cord injury model. Exp Anim 2020; 70:108-118. [PMID: 33071271 PMCID: PMC7887620 DOI: 10.1538/expanim.20-0018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Non-human primates are most suitable for generating cervical experimental models, and it is necessary to study the anatomy of the cervical spine in non-human primates when generating the models. The purpose of this study was to provide the anatomical parameters of the cervical spine and spinal cord in long-tailed macaques (Macaca fascicularis) as a basis for cervical spine-related experimental studies. Cervical spine specimens from 8 male adult subjects were scanned by micro-computed tomography, and an additional 10 live male subjects were scanned by magnetic resonance imaging. The measurements and parameters from them were compared to those of 12 male adult human subjects. Additionally, 10 live male subjects were scanned by magnetic resonance imaging, and the width and depth of the spinal cord and spinal canal and the thickness of the anterior and posterior cerebrospinal fluid were measured and compared to the relevant parameters of 10 male adult human subjects. The tendency of cervical parameters to change with segmental changes was similar between species. The vertebral body, spinal canal, and spinal cord were significantly flatter in the human subjects than in the long-tailed macaques. The cerebrospinal fluid space in the long-tailed macaques was smaller than that in the human subjects. The anatomical features of the cervical vertebrae of long-tailed macaques provide a reference for establishing a preclinical model of cervical spinal cord injury.
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Affiliation(s)
- Junhao Liu
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Zhou Yang
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Xiuhua Wu
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Zucheng Huang
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Zhiping Huang
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Xushi Chen
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Qi Liu
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Hui Jiang
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
| | - Qingan Zhu
- Division of Spinal Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, China
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19
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Benasson I, Wagnac E, Diotalevi L, Moore D, Mac-Thiong JM, Petit Y. Gait analysis of a post induced traumatic spinal cord injury porcine model. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3803-3806. [PMID: 33018829 DOI: 10.1109/embc44109.2020.9175280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Porcine model constitutes a potential translational model to study traumatic spinal cord injuries (TSCI) considering its recent use in numerous studies. Recovery of the animal is currently monitored through a qualitative evaluation of the gait. Adding a quantitative evaluation might help to better assess the functional recovery of the animal. In this study, a new controlled method involving the use of an electro-magnetic actuator was used on a pig to induce a TSCI. Chronic monitoring was done using a quantitative analysis of the gait. Results show both, the injury of the pig and its functional recovery. This large animal model will help to provide a better understanding of injury and recovery mechanisms and thus could constitute a strong preclinical model for future therapeutic studies.Clinical Relevance- Methodology and results from this study would provide a better insight on the functional recovery after traumatic spinal cord injuries.
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20
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Liu J, Li R, Huang Z, Huang Z, Li Y, Wu X, Lin J, Jiang H, Cheng Y, Kong G, Wu X, Liu Q, Liu Y, Yang Z, Li R, Chen J, Fu J, Ramer MS, Kwon BK, Liu J, Kramer JLK, Tetzlaff W, Hu Y, Zhu Q. A Cervical Spinal Cord Hemi-Contusion Injury Model Based on Displacement Control in Non-Human Primates (Macaca fascicularis). J Neurotrauma 2020; 37:1669-1686. [PMID: 32174266 DOI: 10.1089/neu.2019.6822] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Non-human primate (NHP) spinal cord injury (SCI) models can be informative in the evaluation of treatments that show promise in rodent models prior to translation to humans. In the present study, we aimed to establish a cervical spinal hemi-contusion model with controlled displacement and evaluate the abnormalities in behavior, electrophysiology, histology, and magnetic resonance imaging. Twelve adult NHPs were divided into an SCI group (n = 8, 24 and 48 weeks) and a control group (n = 4). An impactor (Φ = 4 mm) was driven to compress the left C5 cord at 800 mm/sec. The contusion displacement and peak force was 4.08 ± 0.17 mm and 19.8 ± 4.6 N. The behavioral assessment showed a consistent dysfunction below the wrist and spontaneous recovery of limb function after injury. Lesion length and lesion area at the epicenter based on T2 hyperintensity were 5.68 ± 0.47 mm and 5.99 ± 0.24 mm2 at 24 weeks post-injury (wpi), and 5.29 ± 0.17 mm and 5.95 ± 0.24 mm2 at 48 wpi. The spared spinal cord area immuno-positive for glial fibrillary acidic protein was significantly reduced, while the staining intensity increased at 24 wpi and 48 wpi, compared with the sham group. Ipsilateral somatosensory and motor evoked potentials were dynamic, increasing in latency and decreasing in amplitude compared with pre-operative values or the contralateral values, and correlated to varying degrees with behavioral outcomes. A shift in size-frequency distribution of sensory neurons of the dorsal root ganglia (DRG) was consistent with a loss of large-diameter cells. The present study demonstrated that the NHP SCI model resulted in consistent unilateral limb dysfunction and potential plasticity in the face of loss of spinal cord and DRG tissue.
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Affiliation(s)
- Junhao Liu
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Rong Li
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zucheng Huang
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhiping Huang
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yuefeng Li
- Guangdong Landau Biotechnology Co. Ltd., Guangzhou, China
| | - Xiaoliang Wu
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Junyu Lin
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Hui Jiang
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yongquan Cheng
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Ganggang Kong
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiuhua Wu
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qi Liu
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yapu Liu
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhou Yang
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Ruoyao Li
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jianting Chen
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Joey Fu
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Matt S Ramer
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian K Kwon
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jie Liu
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - John L K Kramer
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wolfram Tetzlaff
- International Collaboration on Repair Discoveries (ICORD), Blusson Spinal Cord Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Yong Hu
- Department of Orthopedics and Traumatology, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Qingan Zhu
- Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
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21
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Aarabi B, Akhtar-Danesh N, Chryssikos T, Shanmuganathan K, Schwartzbauer GT, Simard JM, Olexa J, Sansur CA, Crandall KM, Mushlin H, Kole MJ, Le EJ, Wessell AP, Pratt N, Cannarsa G, Lomangino C, Scarboro M, Aresco C, Oliver J, Caffes N, Carbine S, Mori K. Efficacy of Ultra-Early (< 12 h), Early (12-24 h), and Late (>24-138.5 h) Surgery with Magnetic Resonance Imaging-Confirmed Decompression in American Spinal Injury Association Impairment Scale Grades A, B, and C Cervical Spinal Cord Injury. J Neurotrauma 2020; 37:448-457. [PMID: 31310155 PMCID: PMC6978784 DOI: 10.1089/neu.2019.6606] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In cervical traumatic spinal cord injury (TSCI), the therapeutic effect of timing of surgery on neurological recovery remains uncertain. Additionally, the relationship between extent of decompression, imaging biomarker evidence of injury severity, and outcome is incompletely understood. We investigated the effect of timing of decompression on long-term neurological outcome in patients with complete spinal cord decompression confirmed on postoperative magnetic resonance imaging (MRI). American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade conversion was determined in 72 AIS grades A, B, and C patients 6 months after confirmed decompression. Thirty-two patients underwent decompressive surgery ultra-early (< 12 h), 25 underwent decompressive surgery early (12-24 h), and 15 underwent decompressive surgery late (> 24-138.5 h) after injury. Age, gender, injury mechanism, intramedullary lesion length (IMLL) on MRI, admission ASIA motor score, and surgical technique were not statistically different among groups. Motor complete patients (p = 0.009) and those with fracture dislocations (p = 0.01) tended to be operated on earlier. Improvement of one grade or more was present in 55.6% of AIS grade A, 60.9% of AIS grade B, and 86.4% of AIS grade C patients. Admission AIS motor score (p = 0.0004) and pre-operative IMLL (p = 0.00001) were the strongest predictors of neurological outcome. AIS grade improvement occurred in 65.6%, 60%, and 80% of patients who underwent decompression ultra-early, early, and late, respectively (p = 0.424). Multiple regression analysis revealed that IMLL was the only significant variable predictive of AIS grade conversion to a better grade (odds ratio, 0.908; confidence interval [CI], 0.862-0.957; p < 0.001). We conclude that in patients with post-operative MRI confirmation of complete decompression following cervical TSCI, pre-operative IMLL, not the timing of surgery, determines long-term neurological outcome.
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Affiliation(s)
- Bizhan Aarabi
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Noori Akhtar-Danesh
- School of Nursing and Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada
| | - Timothy Chryssikos
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | | | - Gary T. Schwartzbauer
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - J. Marc Simard
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Joshua Olexa
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Charles A. Sansur
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kenneth M. Crandall
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Harry Mushlin
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Matthew J. Kole
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Elizabeth J. Le
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Aaron P. Wessell
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Nathan Pratt
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Gregory Cannarsa
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Cara Lomangino
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Maureen Scarboro
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Carla Aresco
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jeffrey Oliver
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Nicholas Caffes
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Stephen Carbine
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kanami Mori
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
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22
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Differences in Morphometric Measures of the Uninjured Porcine Spinal Cord and Dural Sac Predict Histological and Behavioral Outcomes after Traumatic Spinal Cord Injury. J Neurotrauma 2019; 36:3005-3017. [DOI: 10.1089/neu.2018.5930] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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23
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Zhou P, Guan J, Xu P, Zhao J, Zhang C, Zhang B, Mao Y, Cui W. Cell Therapeutic Strategies for Spinal Cord Injury. Adv Wound Care (New Rochelle) 2019; 8:585-605. [PMID: 31637103 PMCID: PMC6798812 DOI: 10.1089/wound.2019.1046] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 08/27/2019] [Indexed: 12/13/2022] Open
Abstract
Significance: Spinal cord injury (SCI) is a neurological disorder that resulted from destroyed long axis of spinal cord, affecting thousands of people every year. With the occurrence of SCI, the lesions can form cystic cavities and produce glial scar, myelin inhibitor, and inflammation that negatively impact repair of spinal cord. Therefore, SCI remains a difficult problem to overcome with present therapeutics. This review of cell therapeutics in SCI provides a systematic review of combinatory therapeutics of SCI and helps the realization of regeneration of spinal cord in the future. Recent Advances: With major breakthroughs in neurobiology in recent years, present therapeutic strategies for SCI mainly aim at nerve regeneration or neuroprotection. For nerve regeneration, the application approaches are tissue engineering and cell transplantation, while drug therapeutics is applied for neuroprotection. Cell therapeutics is a new approach that treats SCI by cell transplantation. Cell therapeutics possesses advantages of neuroprotection, immune regulation, axonal regeneration, neuron relay formation, and remyelination. Critical Issues: Neurons cannot regenerate at the site of injury. Therefore, it is essential to find a repair strategy for remyelination, axon regeneration, and functional recovery. Cell therapeutics is emerging as the most promising approach for treating SCI. Future Directions: The future application of SCI therapy in clinical practice may require a combination of multiple strategies. A comprehensive treatment of injury of spinal cord is the focus of the present research. With the combination of different cell therapy strategies, future experiments will achieve more dramatic success in spinal cord repair.
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Affiliation(s)
- Pinghui Zhou
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
- Anhui Province Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, P.R. China
| | - Jingjing Guan
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Panpan Xu
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Jingwen Zhao
- Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Changchun Zhang
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Bin Zhang
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Yingji Mao
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
- School of Life Science, Bengbu Medical College, Bengbu, P.R. China
| | - Wenguo Cui
- Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
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24
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Pre-Clinical Evaluation of CBD-NT3 Modified Collagen Scaffolds in Completely Spinal Cord Transected Non-Human Primates. J Neurotrauma 2019; 36:2316-2324. [DOI: 10.1089/neu.2018.6078] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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25
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Rosenzweig ES, Salegio EA, Liang JJ, Weber JL, Weinholtz CA, Brock JH, Moseanko R, Hawbecker S, Pender R, Cruzen CL, Iaci JF, Caggiano AO, Blight AR, Haenzi B, Huie JR, Havton LA, Nout-Lomas YS, Fawcett JW, Ferguson AR, Beattie MS, Bresnahan JC, Tuszynski MH. Chondroitinase improves anatomical and functional outcomes after primate spinal cord injury. Nat Neurosci 2019; 22:1269-1275. [PMID: 31235933 PMCID: PMC6693679 DOI: 10.1038/s41593-019-0424-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 05/10/2019] [Indexed: 01/07/2023]
Abstract
Inhibitory extracellular matrices form around mature neurons as perineuronal nets containing chondroitin sulfate proteoglycans (CSPGs) that limit axonal sprouting after CNS injury. The enzyme chondroitinase (Chase) degrades the inhibitory CSPGs and improves axonal sprouting and functional recovery after spinal cord injury (SCI) in rodents. We evaluated the effects of Chase in Rhesus monkeys that had undergone C7 spinal cord hemisection. Four weeks after hemisection, multiple intraparenchymal Chase injections targeted spinal cord circuits controlling hand function below the lesion. Hand function improved significantly in Chase-treated monkeys relative to vehicle-injected controls. Moreover, Chase significantly increased corticospinal axon growth and the number of synapses formed by corticospinal terminals in gray matter caudal to the lesion. No detrimental effects were detected. This approach appears to merit clinical translation in SCI.
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Affiliation(s)
- Ephron S Rosenzweig
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Ernesto A Salegio
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Justine J Liang
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Janet L Weber
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Chase A Weinholtz
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - John H Brock
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA.,Veterans Administration Medical Center, La Jolla, CA, USA
| | - Rod Moseanko
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Stephanie Hawbecker
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Roger Pender
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | - Christina L Cruzen
- California National Primate Research Center, University of California, Davis, Davis, CA, USA
| | | | | | | | | | - J Russell Huie
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Leif A Havton
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yvette S Nout-Lomas
- College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | | | - Adam R Ferguson
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Michael S Beattie
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Jacqueline C Bresnahan
- Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, USA
| | - Mark H Tuszynski
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA. .,Veterans Administration Medical Center, La Jolla, CA, USA.
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26
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Badner A, Vidal PM, Hong J, Hacker J, Fehlings MG. Endogenous Interleukin-10 Deficiency Exacerbates Vascular Pathology in Traumatic Cervical Spinal Cord Injury. J Neurotrauma 2019; 36:2298-2307. [PMID: 30843463 DOI: 10.1089/neu.2018.6081] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Although the majority of traumatic spinal cord injuries (SCIs) take place at the cervical level, pre-clinical studies have been disproportionally focused on thoracic insults. With differences in anatomy, physiology, and immune response between spinal cord levels, there is evidence that injury pathophysiology may vary, requiring tailored treatment paradigms. Further, as only a few therapies have been successfully translated to the clinic, cervical models are increasingly recognized as essential for the characterization of trauma and therapy. Using a novel and clinically relevant cervical contusion-compression mouse model of bilateral incomplete injury, this study aimed to assess the role of interleukin10 (IL-10), a potent cytokine with broad anti-inflammatory effects, in SCI vascular pathology. While the effects of IL-10 loss have been previously evaluated, the vascular changes are poorly characterized. Here, using in vivo high-resolution ultrasound imaging, we demonstrate that IL-10 deficiency is associated with increased acute vascular damage. Importantly, the loss of endogenous IL-10 led to significant differences in the acute systemic response to SCI, specifically the circulating levels of IL-12 (p70), LIX (CXCL5), IL-1β, tumor necrosis factor (TNF)-α, and IL-6 relative to genotype sham controls. These effects also fostered modest impairments in long-term functional recovery, assessed by the Basso Mouse Scale, as well as histological outcomes.
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Affiliation(s)
- Anna Badner
- 1Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,2Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Pia M Vidal
- 1Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - James Hong
- 1Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,2Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Justin Hacker
- 1Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Michael G Fehlings
- 1Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,2Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
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27
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Configuration of electrical spinal cord stimulation through real-time processing of gait kinematics. Nat Protoc 2019; 13:2031-2061. [PMID: 30190556 DOI: 10.1038/s41596-018-0030-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Epidural electrical stimulation (EES) of the spinal cord and real-time processing of gait kinematics are powerful methods for the study of locomotion and the improvement of motor control after injury or in neurological disorders. Here, we describe equipment and surgical procedures that can be used to acquire chronic electromyographic (EMG) recordings from leg muscles and to implant targeted spinal cord stimulation systems that remain stable up to several months after implantation in rats and nonhuman primates. We also detail how to exploit these implants to configure electrical spinal cord stimulation policies that allow control over the degree of extension and flexion of each leg during locomotion. This protocol uses real-time processing of gait kinematics and locomotor performance, and can be configured within a few days. Once configured, stimulation bursts are delivered over specific spinal cord locations with precise timing that reproduces the natural spatiotemporal activation of motoneurons during locomotion. These protocols can also be easily adapted for the safe implantation of systems in the vicinity of the spinal cord and to conduct experiments involving real-time movement feedback and closed-loop controllers.
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28
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Züchner M, Lervik A, Kondratskaya E, Bettembourg V, Zhang L, Haga HA, Boulland JL. Development of a Multimodal Apparatus to Generate Biomechanically Reproducible Spinal Cord Injuries in Large Animals. Front Neurol 2019; 10:223. [PMID: 30941086 PMCID: PMC6433700 DOI: 10.3389/fneur.2019.00223] [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: 11/15/2018] [Accepted: 02/21/2019] [Indexed: 01/08/2023] Open
Abstract
Rodents are widespread animal models in spinal cord injury (SCI) research. They have contributed to obtaining important information. However, some treatments only tested in rodents did not prove efficient in clinical trials. This is probably a result of significant differences in the physiology, anatomy, and complexity between humans and rodents. To bridge this gap in a better way, a few research groups use pig models for SCI. Here we report the development of an apparatus to perform biomechanically reproducible SCI in large animals, including pigs. We present the iterative process of engineering, starting with a weight-drop system to ultimately produce a spring-load impactor. This device allows a graded combination of a contusion and a compression injury. We further engineered a device to entrap the spinal cord and prevent it from escaping at the moment of the impact. In addition, it provides identical resistance around the cord, thereby, optimizing the inter-animal reproducibility. We also present other tools to straighten the vertebral column and to ease the surgery. Sensors mounted on the impactor provide information to assess the inter-animal reproducibility of the impacts. Further evaluation of the injury strength using neurophysiological recordings, MRI scans, and histology shows consistency between impacts. We conclude that this apparatus provides biomechanically reproducible spinal cord injuries in pigs.
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Affiliation(s)
- Mark Züchner
- Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.,Norwegian Center for Stem Cell Research, Oslo University Hospital, Oslo, Norway
| | - Andreas Lervik
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Elena Kondratskaya
- Norwegian Center for Stem Cell Research, Oslo University Hospital, Oslo, Norway
| | - Vanessa Bettembourg
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Lili Zhang
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Henning A Haga
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Jean-Luc Boulland
- Norwegian Center for Stem Cell Research, Oslo University Hospital, Oslo, Norway
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29
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Aarabi B, Olexa J, Chryssikos T, Galvagno SM, Hersh DS, Wessell A, Sansur C, Schwartzbauer G, Crandall K, Shanmuganathan K, Simard JM, Mushlin H, Kole M, Le E, Pratt N, Cannarsa G, Lomangino CD, Scarboro M, Aresco C, Curry B. Extent of Spinal Cord Decompression in Motor Complete (American Spinal Injury Association Impairment Scale Grades A and B) Traumatic Spinal Cord Injury Patients: Post-Operative Magnetic Resonance Imaging Analysis of Standard Operative Approaches. J Neurotrauma 2019; 36:862-876. [PMID: 30215287 PMCID: PMC6484360 DOI: 10.1089/neu.2018.5834] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Although decompressive surgery following traumatic spinal cord injury (TSCI) is recommended, adequate surgical decompression is rarely verified via imaging. We utilized magnetic resonance imaging (MRI) to analyze the rate of spinal cord decompression after surgery. Pre-operative (within 8 h of injury) and post-operative (within 48 h of injury) MRI images of 184 motor complete patients (American Spinal Injury Association Impairment Scale [AIS] grade A = 119, AIS grade B = 65) were reviewed to verify spinal cord decompression. Decompression was defined as the presence of a patent subarachnoid space around a swollen spinal cord. Of the 184 patients, 100 (54.3%) underwent anterior cervical discectomy and fusion (ACDF), and 53 of them also underwent laminectomy. Of the 184 patients, 55 (29.9%) underwent anterior cervical corpectomy and fusion (ACCF), with (26 patients) or without (29 patients) laminectomy. Twenty-nine patients (16%) underwent stand-alone laminectomy. Decompression was verified in 121 patients (66%). The rates of decompression in patients who underwent ACDF and ACCF without laminectomy were 46.8% and 58.6%, respectively. Among these patients, performing a laminectomy increased the rate of decompression (72% and 73.1% of patients, respectively). Twenty-five of 29 (86.2%) patients who underwent a stand-alone laminectomy were found to be successfully decompressed. The rates of decompression among patients who underwent laminectomy at one, two, three, four, or five levels were 58.3%, 68%, 78%, 80%, and 100%, respectively (p < 0.001). In multi-variate logistic regression analysis, only laminectomy was significantly associated with successful decompression (odds ratio 4.85; 95% confidence interval 2.2-10.6; p < 0.001). In motor complete TSCI patients, performing a laminectomy significantly increased the rate of successful spinal cord decompression, independent of whether anterior surgery was performed.
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Affiliation(s)
- Bizhan Aarabi
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Joshua Olexa
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Timothy Chryssikos
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Samuel M. Galvagno
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - David S. Hersh
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Aaron Wessell
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Charles Sansur
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Gary Schwartzbauer
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kenneth Crandall
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kathirkamanathan Shanmuganathan
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Radiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - J. Marc Simard
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Harry Mushlin
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Mathew Kole
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Elizabeth Le
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Nathan Pratt
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Gregory Cannarsa
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Cara D. Lomangino
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Maureen Scarboro
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Carla Aresco
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland
| | - Brian Curry
- Walter Reed National Military Medical Center, Bethesda, Maryland
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30
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Baklaushev VP, Durov OV, Kim SV, Gulaev EV, Gubskiy IL, Konoplyannikov MA, Zabozlaev FG, Zhang C, Agrba VZ, Orlov SV, Lapin BA, Troitskiy AV, Averyanov AV, Ahlfors JE. Development of a motor and somatosensory evoked potentials-guided spinal cord Injury model in non-human primates. J Neurosci Methods 2018; 311:200-214. [PMID: 30393204 DOI: 10.1016/j.jneumeth.2018.10.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 10/22/2018] [Indexed: 02/07/2023]
Abstract
Background Nonhuman primates (NHP) may provide the most adequate (in terms of neuroanatomy and neurophysiology) model of spinal cord injury (SCI) for testing regenerative therapies, but bioethical considerations exclude their use in severe SCI. New Method A reproducible model of SCI at the lower thoracic level has been developed in Rhesus macaques. The model comprises surgical resection of 25% of the spinal cord in the projection of the dorsal funiculus and dorsolateral corticospinal pathways, controlled via registration of intraoperative evoked potentials (EPs). The animals were evaluated using the modified Hindlimb score, MRI, SSEP, and MEP over a time period of 8-12 weeks post-SCI, followed by histological examination. Results Complete disappearance of intraoperative EPs from distal hindlimb muscles without restoration within two weeks post-SCI was an indicator for irreversible disruption of the abovementioned pathways. As a result, controlled damage to the spinal cord was achieved in three NHPs, clinically manifested as irreversible lower monoplegia. No significant functional restoration was observed in these NHPs up to 12 weeks post-SCI. Demyelination of the damaged ascending tracts was detected. Disturbances in pelvic organ function were not observed in all animals. Comparison with existing methods The new method of EPs-guided SCI allows a more controlled and irreversible damage to the spinal cord compared with contusion and other transection approaches. Conclusions This method to induce complete SCI in NHP is well tolerated, reproducible and ethically acceptable: these are valuable attributes in a preclinical model that will hopefully help advance testing of new regenerative therapies in SCI.
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Affiliation(s)
- V P Baklaushev
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia; Institute for Advanced Training, FMBA, Moscow, Russia.
| | - O V Durov
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia
| | - S V Kim
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia
| | - E V Gulaev
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia
| | - I L Gubskiy
- Research and Education Center for Medicinal Nanobiotechnology, Pirogov Russian National Research Medical University, Moscow, Russia
| | - M A Konoplyannikov
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia; Institute of Regenerative Medicine, Sechenov Medical University, Moscow, Russia
| | - F G Zabozlaev
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia
| | - C Zhang
- Research and Education Center for Medicinal Nanobiotechnology, Pirogov Russian National Research Medical University, Moscow, Russia; Department of Bone and Soft Tissue Tumors, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - V Z Agrba
- Institute of Medicinal Primatology Russian Academy of Science, Sochi, Russia
| | - S V Orlov
- Institute of Medicinal Primatology Russian Academy of Science, Sochi, Russia
| | - B A Lapin
- Institute of Medicinal Primatology Russian Academy of Science, Sochi, Russia
| | - A V Troitskiy
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia; Institute for Advanced Training, FMBA, Moscow, Russia
| | - A V Averyanov
- Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, 28 Orekhovy Blvd., 115682 Moscow, Russia
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Krisa L, Runyen M, Detloff MR. Translational Challenges of Rat Models of Upper Extremity Dysfunction After Spinal Cord Injury. Top Spinal Cord Inj Rehabil 2018; 24:195-205. [PMID: 29997423 DOI: 10.1310/sci2403-195] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
There are approximately 17,500 new spinal cord injury (SCI) cases each year in the United States, with the majority of cases resulting from a traumatic injury. Damage to the spinal cord causes either temporary or permanent changes in sensorimotor function. Given that the majority of human SCIs occur in the cervical spinal level, the experimental animal models of forelimb dysfunction play a large role in the ability to translate basic science research to clinical application. However, the variation in the design of clinical and basic science studies of forelimb/upper extremity (UE) function prevents the ease of translation. This review provides an overview of experimental models of forelimb dysfunction used in SCI research with special emphasis on the rat model of SCI. The anatomical location and types of experimental cervical lesions, functional assessments, and rehabilitation strategies used in the basic science laboratory are reviewed. Finally, we discuss the challenges of translating animal models of forelimb dysfunction to the clinical SCI human population.
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Affiliation(s)
- Laura Krisa
- Department of Occupational Therapy, Jefferson College of Health Professions, Jefferson (Philadelphia University + Thomas Jefferson University), Philadelphia, Pennsylvania.,Department of Physical Therapy, Jefferson College of Health Professions, Jefferson (Philadelphia University + Thomas Jefferson University), Philadelphia, Pennsylvania
| | - Madeline Runyen
- Department of Occupational Therapy, Jefferson College of Health Professions, Jefferson (Philadelphia University + Thomas Jefferson University), Philadelphia, Pennsylvania
| | - Megan Ryan Detloff
- Department of Neurobiology & Anatomy, Spinal Cord Research Center, College of Medicine, Drexel University, Philadelphia, Pennsylvania
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32
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Compressive mechanical characterization of non-human primate spinal cord white matter. Acta Biomater 2018; 74:260-269. [PMID: 29729417 DOI: 10.1016/j.actbio.2018.05.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 04/27/2018] [Accepted: 05/01/2018] [Indexed: 11/22/2022]
Abstract
The goal of developing computational models of spinal cord injury (SCI) is to better understand the human injury condition. However, finite element models of human SCI have used rodent spinal cord tissue properties due to a lack of experimental data. Central nervous system tissues in non human primates (NHP) closely resemble that of humans and therefore, it is expected that material constitutive models obtained from NHPs will increase the fidelity and the accuracy of human SCI models. Human SCI most often results from compressive loading and spinal cord white matter properties affect FE predicted patterns of injury; therefore, the objectives of this study were to characterize the unconfined compressive response of NHP spinal cord white matter and present an experimentally derived, finite element tractable constitutive model for the tissue. Cervical spinal cords were harvested from nine male adult NHPs (Macaca mulatta). White matter biopsy samples (3 mm in diameter) were taken from both lateral columns of the spinal cord and were divided into four strain rate groups for unconfined dynamic compression and stress relaxation (post-mortem <1-hour). The NHP spinal cord white matter compressive response was sensitive to strain rate and showed substantial stress relaxation confirming the viscoelastic behavior of the material. An Ogden 1st order model best captured the non-linear behavior of NHP white matter in a quasi-linear viscoelastic material model with 4-term Prony series. This study is the first to characterize NHP spinal cord white matter at high (>10/sec) strain rates typical of traumatic injury. The finite element derived material constitutive model of this study will increase the fidelity of SCI computational models and provide important insights for transferring pre-clinical findings to clinical treatments. STATEMENT OF SIGNIFICANCE Spinal cord injury (SCI) finite element (FE) models provide an important tool to bridge the gap between animal studies and human injury, assess injury prevention technologies (e.g. helmets, seatbelts), and provide insight into the mechanisms of injury. Although, FE model outcomes depend on the assumed material constitutive model, there is limited experimental data for fresh spinal cords and all was obtained from rodent, porcine or bovine tissues. Central nervous system tissues in non human primates (NHP) more closely resemble humans. This study characterizes fresh NHP spinal cord material properties at high strains rates and large deformations typical of SCI for the first time. A constitutive model was defined that can be readily implemented in finite strain FE analysis of SCI.
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Jeffery N, Boudreau CE, Konarik M, Mays T, Fajt V. Pharmacokinetics and safety of oral glyburide in dogs with acute spinal cord injury. PeerJ 2018; 6:e4387. [PMID: 29503767 PMCID: PMC5831157 DOI: 10.7717/peerj.4387] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 01/29/2018] [Indexed: 01/04/2023] Open
Abstract
Background Glyburide (also known as glibenclamide) is effective in reducing the severity of tissue destruction and improving functional outcome after experimental spinal cord injury in rodents and so has promise as a therapy in humans. There are many important differences between spinal cord injury in experimental animals and in human clinical cases, making it difficult to introduce new therapies into clinical practice. Spinal cord injury is also common in pet dogs and requires new effective therapies, meaning that they can act as a translational model for the human condition while also deriving direct benefits from such research. In this study we investigated the pharmacokinetics and safety of glyburide in dogs with clinical spinal cord injury. Methods We recruited dogs that had incurred an acute thoracolumbar spinal cord injury within the previous 72 h. These had become acutely non-ambulatory on the pelvic limbs and were admitted to our veterinary hospitals to undergo anesthesia, cross sectional diagnostic imaging, and surgical decompression. Oral glyburide was given to each dog at a dose of 75 mcg/kg. In five dogs, we measured blood glucose concentrations for 10 h after a single oral dose. In six dogs, we measured serum glyburide and glucose concentrations for 24 h and estimated pharmacokinetic parameters to estimate a suitable dose for use in a subsequent clinical trial in similarly affected dogs. Results No detrimental effects of glyburide administration were detected in any participating dog. Peak serum concentrations of glyburide were attained at a mean of 13 h after dosing, and mean apparent elimination half-life was approximately 7 h. Observed mean maximum plasma concentration was 31 ng/mL. At the glyburide dose administered there was no observable association between glyburide and glucose concentrations in blood. Discussion Our data suggest that glyburide can be safely administered to dogs that are undergoing anesthesia, imaging and surgery for treatment of their acute spinal cord injury and can attain clinically-relevant serum concentrations without developing hazardous hypoglycemia. Serum glyburide concentrations achieved in this study suggest that a loading dose of 150 mcg/kg followed by repeat doses of 75 mcg/kg at 8-hourly intervals would lead to serum glyburide concentrations of 25-50 ng/mL within an acceptably short enough period after oral administration to be appropriate for a clinical trial in canine spinal cord injury.
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Affiliation(s)
- Nick Jeffery
- Department of Small Animal Clinical Sciences, Texas A&M University, College Station, TX, United States of America
| | - C Elizabeth Boudreau
- Department of Small Animal Clinical Sciences, Texas A&M University, College Station, TX, United States of America
| | - Megan Konarik
- Veterinary Medical Diagnostic Laboratory, Texas A&M University, College Station, TX, United States of America
| | - Travis Mays
- Veterinary Medical Diagnostic Laboratory, Texas A&M University, College Station, TX, United States of America
| | - Virginia Fajt
- Department of Veterinary Physiology & Pharmacology, Texas A&M University, College Station, TX, United States of America
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Rosenzweig ES, Brock JH, Lu P, Kumamaru H, Salegio EA, Kadoya K, Weber JL, Liang JJ, Moseanko R, Hawbecker S, Huie JR, Havton LA, Nout-Lomas YS, Ferguson AR, Beattie MS, Bresnahan JC, Tuszynski MH. Restorative effects of human neural stem cell grafts on the primate spinal cord. Nat Med 2018; 24:484-490. [PMID: 29480894 DOI: 10.1038/nm.4502] [Citation(s) in RCA: 209] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 01/26/2018] [Indexed: 12/14/2022]
Abstract
We grafted human spinal cord-derived neural progenitor cells (NPCs) into sites of cervical spinal cord injury in rhesus monkeys (Macaca mulatta). Under three-drug immunosuppression, grafts survived at least 9 months postinjury and expressed both neuronal and glial markers. Monkey axons regenerated into grafts and formed synapses. Hundreds of thousands of human axons extended out from grafts through monkey white matter and synapsed in distal gray matter. Grafts gradually matured over 9 months and improved forelimb function beginning several months after grafting. These findings in a 'preclinical trial' support translation of NPC graft therapy to humans with the objective of reconstituting both a neuronal and glial milieu in the site of spinal cord injury.
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Affiliation(s)
- Ephron S Rosenzweig
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA
| | - John H Brock
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA.,Veterans Administration Medical Center, La Jolla, California, USA
| | - Paul Lu
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA.,Veterans Administration Medical Center, La Jolla, California, USA
| | - Hiromi Kumamaru
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA
| | - Ernesto A Salegio
- California National Primate Research Center, University of California, Davis, Davis, California, USA
| | - Ken Kadoya
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA.,Department of Orthopaedic Surgery, Hokkaido University, Sapporo, Japan
| | - Janet L Weber
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA
| | - Justine J Liang
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA
| | - Rod Moseanko
- California National Primate Research Center, University of California, Davis, Davis, California, USA
| | - Stephanie Hawbecker
- California National Primate Research Center, University of California, Davis, Davis, California, USA
| | - J Russell Huie
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California, USA
| | - Leif A Havton
- Department of Neurology, University of California, Los Angeles, Los Angeles, California, USA
| | - Yvette S Nout-Lomas
- College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Adam R Ferguson
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California, USA.,Veterans Administration Medical Center, San Francisco, California, USA
| | - Michael S Beattie
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California, USA
| | - Jacqueline C Bresnahan
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California, USA
| | - Mark H Tuszynski
- Department of Neurosciences, University of California, San Diego, La Jolla, California, USA.,Veterans Administration Medical Center, La Jolla, California, USA
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Haefeli J, Huie JR, Morioka K, Ferguson AR. Assessments of sensory plasticity after spinal cord injury across species. Neurosci Lett 2017; 652:74-81. [PMID: 28007646 PMCID: PMC5466896 DOI: 10.1016/j.neulet.2016.12.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 12/08/2016] [Accepted: 12/14/2016] [Indexed: 12/26/2022]
Abstract
Spinal cord injury (SCI) is a multifaceted phenomenon associated with alterations in both motor function and sensory function. A majority of patients with SCI report sensory disturbances, including not only loss of sensation, but in many cases enhanced abnormal sensation, dysesthesia and pain. Development of therapeutics to treat these abnormal sensory changes require common measurement tools that can enable cross-species translation from animal models to human patients. We review the current literature on translational nociception/pain measurement in SCI and discuss areas for further development. Although a number of tools exist for measuring both segmental and affective sensory changes, we conclude that there is a pressing need for better, integrative measurement of nociception/pain outcomes across species to enhance precise therapeutic innovation for sensory dysfunction in SCI.
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Affiliation(s)
- Jenny Haefeli
- Weill Institute for Neurosciences, Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, San Francisco, CA, USA.
| | - J Russell Huie
- Weill Institute for Neurosciences, Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, San Francisco, CA, USA.
| | - Kazuhito Morioka
- Weill Institute for Neurosciences, Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, San Francisco, CA, USA.
| | - Adam R Ferguson
- Weill Institute for Neurosciences, Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, San Francisco, CA, USA; San Francisco Veteran's Affairs Medical Center, San Francisco, CA, USA.
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36
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Cell transplantation therapy for spinal cord injury. Nat Neurosci 2017; 20:637-647. [DOI: 10.1038/nn.4541] [Citation(s) in RCA: 435] [Impact Index Per Article: 62.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 02/22/2017] [Indexed: 02/07/2023]
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Moore SA, Granger N, Olby NJ, Spitzbarth I, Jeffery ND, Tipold A, Nout-Lomas YS, da Costa RC, Stein VM, Noble-Haeusslein LJ, Blight AR, Grossman RG, Basso DM, Levine JM. Targeting Translational Successes through CANSORT-SCI: Using Pet Dogs To Identify Effective Treatments for Spinal Cord Injury. J Neurotrauma 2017; 34:2007-2018. [PMID: 28230415 DOI: 10.1089/neu.2016.4745] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Translation of therapeutic interventions for spinal cord injury (SCI) from laboratory to clinic has been historically challenging, highlighting the need for robust models of injury that more closely mirror the human condition. The high prevalence of acute, naturally occurring SCI in pet dogs provides a unique opportunity to evaluate expeditiously promising interventions in a population of animals that receive diagnoses and treatment clinically in a manner similar to persons with SCI, while adhering to National Institutes of Health guidelines for scientific rigor and transparent reporting. In addition, pet dogs with chronic paralysis are often maintained long-term by their owners, offering a similarly unique population for study of chronic SCI. Despite this, only a small number of studies have used the clinical dog model of SCI. The Canine Spinal Cord Injury Consortium (CANSORT-SCI) was recently established by a group of veterinarians and basic science researchers to promote the value of the canine clinical model of SCI. The CANSORT-SCI group held an inaugural meeting November 20 and 21, 2015 to evaluate opportunities and challenges to the use of pet dogs in SCI research. Key challenges identified included lack of familiarity with the model among nonveterinary scientists and questions about how and where in the translational process the canine clinical model would be most valuable. In light of these, we review the natural history, outcome, and available assessment tools associated with canine clinical SCI with emphasis on their relevance to human SCI and the translational process.
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Affiliation(s)
- Sarah A Moore
- 1 Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine , Columbus Ohio.,2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI)
| | - Nicolas Granger
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,3 Faculty of Health Sciences, University of Bristol , Langford, North Somerset, United Kingdom
| | - Natasha J Olby
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,4 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University , Raleigh, North Carolina.,5 Comparative Medicine Institute, North Carolina State University , Raleigh, North Carolina
| | - Ingo Spitzbarth
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,6 Department of Pathology, University of Veterinary Medicine , Hannover, Germany .,7 Center for Systems Neuroscience , Hannover, Germany
| | - Nick D Jeffery
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,8 Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University , College Station, Texas
| | - Andrea Tipold
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,7 Center for Systems Neuroscience , Hannover, Germany.,9 Department of Small Animal Medicine and Surgery, University of Veterinary Medicine , Hannover, Germany
| | - Yvette S Nout-Lomas
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,10 College of Veterinary Medicine and Biomedical Sciences, Colorado State University , Fort Collins, Colorado
| | - Ronaldo C da Costa
- 1 Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine , Columbus Ohio.,2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI)
| | - Veronika M Stein
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,11 Department of Clinical Veterinary Sciences, University of Bern , Bern, Switzerland
| | - Linda J Noble-Haeusslein
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,12 Departments of Physical Therapy and Rehabilitation Sciences and Neurological Surgery, University of California , San Francisco, San Francisco, California
| | - Andrew R Blight
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,13 Acorda Therapeutics, Inc. Ardsley, New York
| | - Robert G Grossman
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,14 Department of Neurosurgery, Houston Methodist Neurological Institute , Houston, Texas
| | - D Michele Basso
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,15 School of Health and Rehabilitation Sciences, The Ohio State University , Columbus, Ohio
| | - Jonathan M Levine
- 2 The Canine Spinal Cord Injury Consortium (CANSORT-SCI).,8 Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University , College Station, Texas
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38
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Jannesar S, Nadler B, Sparrey CJ. The Transverse Isotropy of Spinal Cord White Matter Under Dynamic Load. J Biomech Eng 2016; 138:2536524. [DOI: 10.1115/1.4034171] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Indexed: 01/31/2023]
Abstract
The rostral-caudally aligned fiber-reinforced structure of spinal cord white matter (WM) gives rise to transverse isotropy in the material. Stress and strain patterns generated in the spinal cord parenchyma following spinal cord injury (SCI) are multidirectional and dependent on the mechanism of the injury. Our objective was to develop a WM constitutive model that captures the material transverse isotropy under dynamic loading. The WM mechanical behavior was extracted from the published tensile and compressive experiments. Combinations of isotropic and fiber-reinforcing models were examined in a conditional quasi-linear viscoelastic (QLV) formulation to capture the WM mechanical behavior. The effect of WM transverse isotropy on SCI model outcomes was evaluated by simulating a nonhuman primate (NHP) contusion injury experiment. A second-order reduced polynomial hyperelastic energy potential conditionally combined with a quadratic reinforcing function in a four-term Prony series QLV model best captured the WM mechanical behavior (0.89 < R2 < 0.99). WM isotropic and transversely isotropic material models combined with discrete modeling of the pia mater resulted in peak impact forces that matched the experimental outcomes. The transversely isotropic WM with discrete pia mater resulted in maximum principal strain (MPS) distributions which effectively captured the combination of ipsilateral peripheral WM sparing, ipsilateral injury and contralateral sparing, and the rostral/caudal spread of damage observed in in vivo injuries. The results suggest that the WM transverse isotropy could have an important role in correlating tissue damage with mechanical measures and explaining the directional sensitivity of the spinal cord to injury.
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Affiliation(s)
- Shervin Jannesar
- Department of Mechatronic Systems Engineering, Simon Fraser University, 250-13450 102 Avenue, Surrey, BC V3T 0A3, Canada e-mail:
| | - Ben Nadler
- Department of Mechanical Engineering, University of Victoria, Victoria, BC, Canada e-mail:
| | - Carolyn J. Sparrey
- Department of Mechatronic Systems Engineering, Simon Fraser University, 250-13450 102 Avenue, Surrey, BC V3T 0A3, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, BC V5Z 1M9, Canada e-mail:
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Sparrey CJ, Salegio EA, Camisa W, Tam H, Beattie MS, Bresnahan JC. Mechanical Design and Analysis of a Unilateral Cervical Spinal Cord Contusion Injury Model in Non-Human Primates. J Neurotrauma 2016; 33:1136-49. [PMID: 26670940 DOI: 10.1089/neu.2015.3974] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Non-human primate (NHP) models of spinal cord injury better reflect human injury and provide a better foundation to evaluate potential treatments and functional outcomes. We combined finite element (FE) and surrogate models with impact data derived from in vivo experiments to define the impact mechanics needed to generate a moderate severity unilateral cervical contusion injury in NHPs (Macaca mulatta). Three independent variables (impactor displacement, alignment, and pre-load) were examined to determine their effects on tissue level stresses and strains. Mechanical measures of peak force, peak displacement, peak energy, and tissue stiffness were analyzed as potential determinants of injury severity. Data generated from FE simulations predicted a lateral shift of the spinal cord at high levels of compression (>64%) during impact. Submillimeter changes in mediolateral impactor position over the midline increased peak impact forces (>50%). Surrogate cords established a 0.5 N pre-load protocol for positioning the impactor tip onto the dural surface to define a consistent dorsoventral baseline position before impact, which corresponded with cerebrospinal fluid displacement and entrapment of the spinal cord against the vertebral canal. Based on our simulations, impactor alignment and pre-load were strong contributors to the variable mechanical and functional outcomes observed in in vivo experiments. Peak displacement of 4 mm after a 0.5N pre-load aligned 0.5-1.0 mm over the midline should result in a moderate severity injury; however, the observed peak force and calculated peak energy and tissue stiffness are required to properly characterize the severity and variability of in vivo NHP contusion injuries.
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Affiliation(s)
- Carolyn J Sparrey
- 1 Mechatronic Systems Engineering, Simon Fraser University , Surrey, British Columbia, Canada .,2 International Collaboration on Repair Discoveries (ICORD) , Vancouver, British Columbia, Canada
| | - Ernesto A Salegio
- 3 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California at San Francisco , San Francisco, California
| | - William Camisa
- 4 Taylor Collaboration, St Mary's Medical Center , San Francisco, California
| | - Horace Tam
- 1 Mechatronic Systems Engineering, Simon Fraser University , Surrey, British Columbia, Canada
| | - Michael S Beattie
- 3 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California at San Francisco , San Francisco, California
| | - Jacqueline C Bresnahan
- 3 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California at San Francisco , San Francisco, California
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