1
|
Nielsen TGNDS, Dancause N, Janjua TAM, Andreis FR, Kjærgaard B, Jensen W. Porcine Model of Cerebral Ischemic Stroke Utilizing Intracortical Recordings for the Continuous Monitoring of the Ischemic Area. SENSORS (BASEL, SWITZERLAND) 2024; 24:2967. [PMID: 38793822 PMCID: PMC11124877 DOI: 10.3390/s24102967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 05/01/2024] [Accepted: 05/03/2024] [Indexed: 05/26/2024]
Abstract
PURPOSE Our aim was to use intracortical recording to enable the tracking of ischemic infarct development over the first few critical hours of ischemia with a high time resolution in pigs. We employed electrophysiological measurements to obtain quick feedback on neural function, which might be useful for screening, e.g., for the optimal dosage and timing of agents prior to further pre-clinical evaluation. METHODS Micro-electrode arrays containing 16 (animal 1) or 32 electrodes (animal 2-7) were implanted in the primary somatosensory cortex of seven female pigs, and continuous electrical stimulation was applied at 0.2 Hz to a cuff electrode implanted on the ulnar nerve. Ischemic stroke was induced after 30 min of baseline recording by injection of endothelin-1 onto the cortex adjacent to the micro-electrode array. Evoked responses were extracted over a moving window of 180 s and averaged across channels as a measure of cortical excitability. RESULTS Across the animals, the cortical excitability was significantly reduced in all seven 30 min segments following endothelin-1 injection, as compared to the 30 min preceding this intervention. This difference was not explained by changes in the anesthesia, ventilation, end-tidal CO2, mean blood pressure, heart rate, blood oxygenation, or core temperature, which all remained stable throughout the experiment. CONCLUSIONS The animal model may assist in maturing neuroprotective approaches by testing them in an accessible model of resemblance to human neural and cardiovascular physiology and body size. This would constitute an intermediate step for translating positive results from rodent studies into human application, by more efficiently enabling effective optimization prior to chronic pre-clinical studies in large animals.
Collapse
Affiliation(s)
| | - Numa Dancause
- Département de Neurosciences, Université de Montréal, C.P. 6128 Succursale Centre-Ville, Montréal, QC H3C 3J7, Canada
| | - Taha Al Muhammadee Janjua
- Center for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Aalborg University, Selma Lagerløfs Vej 249, 9260 Gistrup, Denmark
| | - Felipe Rettore Andreis
- Center for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Aalborg University, Selma Lagerløfs Vej 249, 9260 Gistrup, Denmark
| | - Benedict Kjærgaard
- Department of Cardiothoracic Surgery, Aalborg University Hospital, Hobrovej 18, 9000 Aalborg, Denmark
| | - Winnie Jensen
- Bevica Center, Department of Health Science and Technology, Aalborg University, Selma Lagerløfs Vej 249, 9260 Gistrup, Denmark
- Center for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Aalborg University, Selma Lagerløfs Vej 249, 9260 Gistrup, Denmark
| |
Collapse
|
2
|
NMDA attenuates the neurovascular response to hypercapnia in the neonatal cerebral cortex. Sci Rep 2019; 9:18900. [PMID: 31827200 PMCID: PMC6906464 DOI: 10.1038/s41598-019-55468-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 11/29/2019] [Indexed: 11/12/2022] Open
Abstract
Cortical spreading depolarization (SD) involves activation of NMDA receptors and elicit neurovascular unit dysfunction. NMDA cannot trigger SD in newborns, thus its effect on neurovascular function is not confounded by other aspects of SD. The present study investigated if NMDA affected hypercapnia-induced microvascular and electrophysiological responses in the cerebral cortex of newborn pigs. Anesthetized piglets were fitted with cranial windows over the parietal cortex to study hemodynamic and electrophysiological responses to graded hypercapnia before/after topically applied NMDA assessed with laser-speckle contrast imaging and recording of local field potentials (LFP)/neuronal firing, respectively. NMDA increased cortical blood flow (CoBF), suppressed LFP power in most frequency bands but evoked a 2.5 Hz δ oscillation. The CoBF response to hypercapnia was abolished after NMDA and the hypercapnia-induced biphasic changes in δ and θ LFP power were also altered. MK-801 prevented NMDA-induced increases in CoBF and the attenuation of microvascular reactivity to hypercapnia. The neuronal nitric oxide synthase (nNOS) inhibitor (N-(4 S)-4-amino-5-[aminoethyl]aminopentyl-N′-nitroguanidin) also significantly preserved the CoBF response to hypercapnia after NMDA, although it didn’t reduce NMDA-induced increases in CoBF. In conclusion, excess activation of NMDA receptors alone can elicit SD-like neurovascular unit dysfunction involving nNOS activity.
Collapse
|
3
|
Oribe S, Yoshida S, Kusama S, Osawa SI, Nakagawa A, Iwasaki M, Tominaga T, Nishizawa M. Hydrogel-Based Organic Subdural Electrode with High Conformability to Brain Surface. Sci Rep 2019; 9:13379. [PMID: 31527626 PMCID: PMC6746719 DOI: 10.1038/s41598-019-49772-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/28/2019] [Indexed: 11/16/2022] Open
Abstract
A totally soft organic subdural electrode has been developed by embedding an array of poly(3,4-ethylenedioxythiophene)-modified carbon fabric (PEDOT-CF) into the polyvinyl alcohol (PVA) hydrogel substrate. The mesh structure of the stretchable PEDOT-CF allowed stable structural integration with the PVA substrate. The electrode performance for monitoring electrocorticography (ECoG) was evaluated in saline solution, on ex vivo brains, and in vivo animal experiments using rats and porcines. It was demonstrated that the large double-layer capacitance of the PEDOT-CF brings low impedance at the frequency of brain wave including epileptic seizures, and PVA hydrogel substrate minimized the contact impedance on the brain. The most important unique feature of the hydrogel-based ECoG electrode was its shape conformability to enable tight adhesion even to curved, grooved surface of brains by just being placed. In addition, since the hydrogel-based electrode is totally organic, the simultaneous ECoG-fMRI measurements could be conducted without image artifacts, avoiding problems induced by conventional metallic electrodes.
Collapse
Affiliation(s)
- Shuntaro Oribe
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Shotaro Yoshida
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki-Aoba, Aoba-ku, Sendai, 980-8579, Japan
| | - Shinya Kusama
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki-Aoba, Aoba-ku, Sendai, 980-8579, Japan
| | - Shin-Ichiro Osawa
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Atsuhiro Nakagawa
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry (NCNP), 4-1-1 Ogawahigashi-cho, Kodaira-shi, Tokyo, 187-8551, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Matsuhiko Nishizawa
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki-Aoba, Aoba-ku, Sendai, 980-8579, Japan.
| |
Collapse
|
4
|
Tavildar S, Mogen B, Zanos S, Seeman S, Perlmutter S, Fetz E, Ashrafi A. Inferring Cortical Connectivity from ECoG Signals Using Graph Signal Processing. IEEE ACCESS : PRACTICAL INNOVATIONS, OPEN SOLUTIONS 2019; 7:109349-109362. [PMID: 36883134 PMCID: PMC9988241 DOI: 10.1109/access.2019.2934490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A novel method to characterize connectivity between sites in the cerebral cortex of primates is proposed in this paper. Connectivity graphs for two macaque monkeys are inferred from Electrocorticographic (ECoG) activity recorded while the animals were alert. The locations of ECoG electrodes are considered as nodes of the graph, the coefficients of the auto-regressive (AR) representation of the signals measured at each node are considered as the signal on the graph and the connectivity strengths between the nodes are considered as the edges of the graph. Maximization of the graph smoothness defined from the Laplacian quadratic form is used to infer the connectivity map (adjacency matrix of the graph). The cortical evoked potential (CEP) map was obtained by stimulating different electrodes and recording the evoked potentials at the other electrodes. The maps obtained by the graph inference and the traditional method of spectral coherence are compared with the CEP map. The results show that the proposed method provides a description of cortical connectivity that is more similar to the stimulation-based measures than spectral coherence. The results are also tested by the surrogate map analysis in which the CEP map is randomly permuted and the distribution of the errors is obtained. It is shown that error between the two maps is comfortably outside the surrogate map error distribution. This indicates that the similarity between the map calculated by the graph inference and the CEP map is statistically significant.
Collapse
Affiliation(s)
- Siddhi Tavildar
- Computational Science Research Center, San Diego State University, San Diego CA, USA
- Center for Neurotechnology, Seattle WA, USA
| | - Brian Mogen
- Center for Neurotechnology, Seattle WA, USA
- Department of Bioengineering, Univ of Washington, Seattle WA, USA
| | - Stavros Zanos
- Center for Neurotechnology, Seattle WA, USA
- WA National Primate Research Center, Univ of Washington, Seattle WA, USA
- Center for Bioelectronic Medicine, Feinstein Institute for Medical Research, Manhasset NY, USA
| | - Stephanie Seeman
- Center for Neurotechnology, Seattle WA, USA
- Dept. Physiology & Biophysics, University of Washington, Seattle WA, USA
| | - Steve Perlmutter
- Center for Neurotechnology, Seattle WA, USA
- WA National Primate Research Center, Univ of Washington, Seattle WA, USA
- Dept. Physiology & Biophysics, University of Washington, Seattle WA, USA
| | - Eberhard Fetz
- Center for Neurotechnology, Seattle WA, USA
- WA National Primate Research Center, Univ of Washington, Seattle WA, USA
- Dept. Physiology & Biophysics, University of Washington, Seattle WA, USA
| | - Ashkan Ashrafi
- Computational Science Research Center, San Diego State University, San Diego CA, USA
- Center for Neurotechnology, Seattle WA, USA
- Department of Electrical and Computer Engineering, San Diego State University, San Diego CA, USA
| |
Collapse
|
5
|
Casimo K, Levinson LH, Zanos S, Gkogkidis CA, Ball T, Fetz E, Weaver KE, Ojemann JG. An interspecies comparative study of invasive electrophysiological functional connectivity. Brain Behav 2017; 7:e00863. [PMID: 29299382 PMCID: PMC5745242 DOI: 10.1002/brb3.863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 09/27/2017] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Resting-state connectivity patterns have been observed in humans and other mammal species, and can be recorded using a variety of different technologies. Functional connectivity has been previously compared between species using resting-state fMRI, but not in electrophysiological studies. METHODS We compared connectivity with implanted electrodes in humans (electrocorticography) to macaques and sheep (microelectrocorticography), which are capable of recording neural data at high frequencies with spatial precision. We specifically examined synchrony, implicated in functional integration between regions. RESULTS We found that connectivity strength was overwhelmingly similar in humans and monkeys for pairs of two different brain regions (prefrontal, motor, premotor, parietal), but differed more often within single brain regions. The two connectivity measures, correlation and phase locking value, were similar in most comparisons. Connectivity strength agreed more often between the species at higher frequencies. Where the species differed, monkey synchrony was stronger than human in all but one case. In contrast, human and sheep connectivity within somatosensory cortex diverged in almost all frequencies, with human connectivity stronger than sheep. DISCUSSION Our findings imply greater heterogeneity within regions in humans than in monkeys, but comparable functional interactions between regions in the two species. This suggests that monkeys may be effectively used to probe resting-state connectivity in humans, and that such findings can then be validated in humans. Although the discrepancy between humans and sheep is larger, we suggest that findings from sheep in highly invasive studies may be used to provide guidance for studies in other species.
Collapse
Affiliation(s)
- Kaitlyn Casimo
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA
| | | | - Stavros Zanos
- Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA.,Department of Physiology and Biophysics University of Washington Seattle WA USA.,Washington National Primate Research Center University of Washington Seattle WA USA.,Feinstein Institute for Medical Research New York City NY USA
| | - C Alexis Gkogkidis
- Translational Neurotechnology Laboratory Department of Neurosurgery Faculty of Medicine Medical Center - University of Freiburg Freiburg Germany.,Laboratory for Biomedical Microtechnology Department of Microsystems Engineering Faculty of Engineering University of Freiburg Freiburg Germany
| | - Tonio Ball
- Translational Neurotechnology Laboratory Department of Neurosurgery Faculty of Medicine Medical Center - University of Freiburg Freiburg Germany.,Laboratory for Biomedical Microtechnology Department of Microsystems Engineering Faculty of Engineering University of Freiburg Freiburg Germany
| | - Eberhard Fetz
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA.,Department of Physiology and Biophysics University of Washington Seattle WA USA.,Washington National Primate Research Center University of Washington Seattle WA USA
| | - Kurt E Weaver
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Department of Radiology University of Washington Seattle WA USA.,Integrated Brain Imaging Center University of Washington Seattle WA USA
| | - Jeffrey G Ojemann
- Graduate Program in Neuroscience University of Washington Seattle WA USA.,Center for Sensorimotor Neural Engineering University of Washington Seattle WA USA.,Department of Neurological Surgery University of Washington Seattle WA USA.,Department of Neurological Surgery Seattle Children's Hospital Seattle WA USA
| |
Collapse
|