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Mattos DJS, Rutlin J, Hong X, Zinn K, Shimony JS, Carter AR. The Role of Extra-motor Networks in Upper Limb Motor Performance Post-stroke. Neuroscience 2023; 514:1-13. [PMID: 36736882 PMCID: PMC11009936 DOI: 10.1016/j.neuroscience.2023.01.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/20/2023] [Accepted: 01/25/2023] [Indexed: 02/04/2023]
Abstract
BACKGROUND Motor improvement post-stroke may happen even if resting state functional connectivity between the ipsilesional and contralesional components of the sensorimotor network is not fully recovered. Therefore, we investigated which extra-motor networks might support upper limb motor gains in response to treatment post-stroke. METHODS Both resting state functional connectivity and upper limb capacity were measured prior to and after an 8-week intervention of task-specific training in 29 human participants [59.24 ± (SD) 10.40 yrs., 12 females and 17 males] with chronic stroke. The sensorimotor and five extra-motor networks were defined: default mode, frontoparietal, cingulo-opercular, dorsal attention network, and salience networks. The Network Level Analysis toolbox was used to identify network pairs whose connectivities were enriched in connectome-behavior relationships. RESULTS Mean upper limb capacity score increased 5.45 ± (SD) 5.55 following treatment. Baseline connectivity of some motor but mostly extra-motor network interactions of cingulo-opercular and default-mode networks were predictive of upper limb capacity following treatment. Also, changes in connectivity for extra-motor interactions of salience with default mode, cingulo-opercular, and dorsal attention networks were correlated with gains in upper limb capacity. CONCLUSIONS These connectome-behavior patterns suggest larger involvement of cingulo-opercular networks in prediction of treatment response and of salience networks in maintenance of improved skilled behavior. These results support our hypothesis that cognitive networks may contribute to recovery of motor performance after stroke and provide additional insights into the neural correlates of intensive training.
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Affiliation(s)
- Daniela J S Mattos
- Departments of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Jerrel Rutlin
- Departments of Psychiatry, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Xin Hong
- Departments of Genetics, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Kristina Zinn
- Departments of Radiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Joshua S Shimony
- Departments of Radiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Alexandre R Carter
- Departments of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA
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Siddiqi SH, Kandala S, Hacker CD, Trapp NT, Leuthardt EC, Carter AR, Brody DL. Individualized precision targeting of dorsal attention and default mode networks with rTMS in traumatic brain injury-associated depression. Sci Rep 2023; 13:4052. [PMID: 36906616 PMCID: PMC10008633 DOI: 10.1038/s41598-022-21905-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 10/05/2022] [Indexed: 03/13/2023] Open
Abstract
At the group level, antidepressant efficacy of rTMS targets is inversely related to their normative connectivity with subgenual anterior cingulate cortex (sgACC). Individualized connectivity may yield better targets, particularly in patients with neuropsychiatric disorders who may have aberrant connectivity. However, sgACC connectivity shows poor test-retest reliability at the individual level. Individualized resting-state network mapping (RSNM) can reliably map inter-individual variability in brain network organization. Thus, we sought to identify individualized RSNM-based rTMS targets that reliably target the sgACC connectivity profile. We used RSNM to identify network-based rTMS targets in 10 healthy controls and 13 individuals with traumatic brain injury-associated depression (TBI-D). These "RSNM targets" were compared with consensus structural targets and targets based on individualized anti-correlation with a group-mean-derived sgACC region ("sgACC-derived targets"). The TBI-D cohort was also randomized to receive active (n = 9) or sham (n = 4) rTMS to RSNM targets with 20 daily sessions of sequential high-frequency left-sided stimulation and low-frequency right-sided stimulation. We found that the group-mean sgACC connectivity profile was reliably estimated by individualized correlation with default mode network (DMN) and anti-correlation with dorsal attention network (DAN). Individualized RSNM targets were thus identified based on DAN anti-correlation and DMN correlation. These RSNM targets showed greater test-retest reliability than sgACC-derived targets. Counterintuitively, anti-correlation with the group-mean sgACC connectivity profile was also stronger and more reliable for RSNM-derived targets than for sgACC-derived targets. Improvement in depression after RSNM-targeted rTMS was predicted by target anti-correlation with the portions of sgACC. Active treatment also led to increased connectivity within and between the stimulation sites, the sgACC, and the DMN. Overall, these results suggest that RSNM may enable reliable individualized rTMS targeting, although further research is needed to determine whether this personalized approach can improve clinical outcomes.
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Affiliation(s)
- Shan H Siddiqi
- Department of Psychiatry, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA. .,Center for Brain Circuit Therapeutics, Brigham & Women's Hospital, 60 Fenwood Rd, Boston, MA, 02115, USA. .,Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd, Bethesda, MD, 20814, USA.
| | - Sridhar Kandala
- Department of Psychiatry, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA
| | - Carl D Hacker
- Department of Neurosurgery, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA
| | - Nicholas T Trapp
- Department of Psychiatry, University of Iowa Carver College of Medicine, 500 Newton Rd, Iowa City, IA, 52246, USA
| | - Eric C Leuthardt
- Department of Neurosurgery, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA
| | - Alexandre R Carter
- Department of Neurology, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA
| | - David L Brody
- Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd, Bethesda, MD, 20814, USA.,Department of Neurology, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA
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Barrett AM, Goedert KM, Carter AR, Chaudhari A. Spatial neglect treatment: The brain's spatial-motor Aiming systems. Neuropsychol Rehabil 2022; 32:662-688. [PMID: 33941021 PMCID: PMC9632633 DOI: 10.1080/09602011.2020.1862678] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 10/29/2020] [Indexed: 10/21/2022]
Abstract
Animal and human literature supports spatial-motor "Aiming" bias, a frontal-subcortical syndrome, as a core deficit in spatial neglect. However, spatial neglect treatment studies rarely assess Aiming errors. Two knowledge gaps result: spatial neglect rehabilitation studies fail to capture the impact on motor-exploratory aspects of functional disability. Also, across spatial neglect treatment studies, discrepant treatment effects may also result from sampling different proportions of patients with Aiming bias. We review behavioural evidence for Aiming spatial neglect, and demonstrate the importance of measuring and targeting Aiming bias for treatment, by reviewing literature on Aiming spatial neglect and prism adaptation treatment, and presenting new preliminary data on bromocriptine treatment. Finally, we review neuroanatomical and network disruption that may give rise to Aiming spatial neglect. Because Aiming spatial neglect predicts prism adaptation treatment response, assessment may broaden the ability of rehabilitation research to capture functionally-relevant disability. Frontal brain lesions predict both the presence of Aiming spatial neglect, and a robust response to some spatial neglect interventions. Research is needed that co-stratifies spatial neglect patients by lesion location and Aiming spatial neglect, to personalize spatial neglect rehabilitation and perhaps even open a path to spatial retraining as a means of promoting better mobility after stroke.
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Affiliation(s)
- A M Barrett
- Neurorehabilitation Division, Emory Brain Health Center, and Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health System, Decatur, GA, USA
| | - Kelly M Goedert
- Department of Psychology, Seton Hall University, South Orange, NJ, USA
| | - Alexandre R Carter
- Neurorehabilitation Division, Department of Neurology, Washington University School of Medicine, Saint Louis, MO, USA
- Program in Occupational Therapy, Washington University in Saint Louis, Saint Louis, MO, USA
| | - Amit Chaudhari
- Department of Neurology, University of California Irvine, Irvine, CA, USA
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Das S, Postman W, Haboubi MA, Akca O, Remmel K, Carter AR, Zazulia A. A case of aphemia following non-dominant sub-insular stroke: unveiling the Foix-Chavany-Marie phenomenon. Neurocase 2021; 27:281-286. [PMID: 34176440 DOI: 10.1080/13554794.2021.1933541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Aphemia refers to the clinical syndrome of inability to orally produce speech with intact comprehension and written expression. Aphemia has been primarily reported in dominant frontal lobe strokes resulting in apraxia of speech (AoS), and in Foix-Chavany-Marie (FCM) syndrome where bilateral opercular or sub-opercular lesions result in anarthria due to deafferentation of brainstem nuclei supplying the oro-facio-lingual and pharyngeal musculature. Aphemia is not reported in non-dominant sub-insular strokes. Here, we present a case of aphemia following non-dominant sub-insular stroke in a patient who had previously recovered from a homologous dominant sub-insular stroke without any apparent residual deficits. We discuss the accepted definitions, theories and controversies in the use of the terminology - aphemia, apraxia of speech (AoS), anarthria related to FCM syndrome, a concomitant pathology - unilateral upper motor neuron (UUMN) dysarthria, and their neuro-anatomical bases. We also highlight the importance of attributing localization value to sequential homologous lesions of the brain that can unveil symptoms due to a "loss of compensation phenomenon" that we propose be termed as "FCM phenomenon." These pathological mechanisms may alone or in certain combinations contribute to the clinical syndrome of aphemia included in the diagnostic approach proposed here. The distinction between these mechanisms requires serial careful neurological examination and detailed speech evaluation including in the recovery phase.
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Affiliation(s)
- Saurav Das
- Vascular Neurology Fellow, Washington University School of Medicine, St. Louis, MO, USA
| | - Whitney Postman
- Director of Neurorehabilitation and Language Laboratory, Department of Communication Sciences and Disorders, Saint Louis University, St. Louis, MO, USA
| | - Michael A Haboubi
- Comprehensive Stroke Center and Department of Neurology, University of Louisville School of Medicine, Louisville, KY, USA
| | - Ozan Akca
- Vice Chair for Research and Professor, Department of Anesthesiology and Perioperative Medicine, Director, Stroke ICU, Comprehensive Stroke Center Clinical Research Program (CSCRP, University of Louisville, Louisville, Kentucky, USA
| | - Kerri Remmel
- Chair, Department of Neurology, University of Louisville; Director, Comprehensive Stroke Center, Comprehensive Stroke Center Clinical Research Program (CSCRP, University of Louisville Hospital, Louisville, Kentucky, USA
| | - Alexandre R Carter
- Division of Neurorehabilitation, Washington University School of Medicine, St. Louis, MO, USA
| | - Allyson Zazulia
- Neurology and Radiology, Associate Dean for Continuing Medical Education, Washington University School of Medicine, St. Louis, MO, USA
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Mattos DJS, Rutlin J, Hong X, Zinn K, Shimony JS, Carter AR. White matter integrity of contralesional and transcallosal tracts may predict response to upper limb task-specific training in chronic stroke. Neuroimage Clin 2021; 31:102710. [PMID: 34126348 PMCID: PMC8209270 DOI: 10.1016/j.nicl.2021.102710] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 11/19/2022]
Abstract
Increase in upper limb function post task specific training in chronic stroke. Motor improvements were not accompanied by changes in white matter integrity. Integrity in contralesional fibers predicted larger motor recovery in Responders. Non-responders had more severe damage of transcallosal fibers than Responders.
Objective To investigate white matter (WM) plasticity induced by intensive upper limb (UL) task specific training (TST) in chronic stroke. Methods Diffusion tensor imaging data and UL function measured by the Action Research Arm Test (ARAT) were collected in 30 individuals with chronic stroke prior to and after intensive TST. ANOVAs tested the effects of training on the entire sample and on the Responders [ΔARAT ≥ 5.8, N = 13] and Non-Responders [ΔARAT < 5.8, N = 17] groups. Baseline fractional anisotropy (FA) values were correlated with ARATpost TST controlling for baseline ARAT and age to identify voxels predictive of response to TST. Results. While ARAT scores increased following training (p < 0.0001), FA changes within major WM tracts were not significant at p < 0.05. In the Responder group, larger baseline FA of both contralesional (CL) and transcallosal tracts predicted larger ARAT scores post-TST. Subcortical lesions and more severe damage to transcallosal tracts were more pronounced in the Non-Responder than in the Responder group. Conclusions The motor improvements post-TST in the Responder group may reflect the engagement of interhemispheric processes not available to the Non-Responder group. Future studies should clarify differences in the role of CL and transcallosal pathways as biomarkers of recovery in response to training for individuals with cortical and subcortical stroke. This knowledge may help to identify sources of heterogeneity in stroke recovery, which is necessary for the development of customized rehabilitation interventions.
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Affiliation(s)
- Daniela J S Mattos
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Jerrel Rutlin
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Xin Hong
- Department of Genetics, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Kristina Zinn
- Department of Radiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Joshua S Shimony
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Alexandre R Carter
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110 USA.
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Newbold DJ, Laumann TO, Hoyt CR, Hampton JM, Montez DF, Raut RV, Ortega M, Mitra A, Nielsen AN, Miller DB, Adeyemo B, Nguyen AL, Scheidter KM, Tanenbaum AB, Van AN, Marek S, Schlaggar BL, Carter AR, Greene DJ, Gordon EM, Raichle ME, Petersen SE, Snyder AZ, Dosenbach NUF. Plasticity and Spontaneous Activity Pulses in Disused Human Brain Circuits. Neuron 2020; 107:580-589.e6. [PMID: 32778224 PMCID: PMC7419711 DOI: 10.1016/j.neuron.2020.05.007] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/12/2020] [Accepted: 05/06/2020] [Indexed: 11/16/2022]
Abstract
To induce brain plasticity in humans, we casted the dominant upper extremity for 2 weeks and tracked changes in functional connectivity using daily 30-min scans of resting-state functional MRI (rs-fMRI). Casting caused cortical and cerebellar regions controlling the disused extremity to functionally disconnect from the rest of the somatomotor system, while internal connectivity within the disused sub-circuit was maintained. Functional disconnection was evident within 48 h, progressed throughout the cast period, and reversed after cast removal. During the cast period, large, spontaneous pulses of activity propagated through the disused somatomotor sub-circuit. The adult brain seems to rely on regular use to maintain its functional architecture. Disuse-driven spontaneous activity pulses may help preserve functionally disconnected sub-circuits.
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Affiliation(s)
- Dillan J Newbold
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Timothy O Laumann
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Catherine R Hoyt
- Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jacqueline M Hampton
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David F Montez
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ryan V Raut
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Mario Ortega
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Anish Mitra
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Psychiatry, Stanford University, Stanford, CA 94305, USA
| | - Ashley N Nielsen
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Institute for Innovations in Developmental Sciences, Northwestern University, Chicago, IL 60611, USA
| | - Derek B Miller
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Babatunde Adeyemo
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Annie L Nguyen
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kristen M Scheidter
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Aaron B Tanenbaum
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Andrew N Van
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Scott Marek
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Bradley L Schlaggar
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Kennedy Krieger Institute, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Alexandre R Carter
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Deanna J Greene
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Evan M Gordon
- VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX 76711, USA; Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX 75080, USA; Department of Psychology and Neuroscience, Baylor University, Waco, TX 76706, USA
| | - Marcus E Raichle
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Steven E Petersen
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Psychological and Brain Sciences, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Abraham Z Snyder
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Nico U F Dosenbach
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA; Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63110, USA; Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Siddiqi SH, Trapp NT, Shahim P, Hacker CD, Laumann TO, Kandala S, Carter AR, Brody DL. Individualized Connectome-Targeted Transcranial Magnetic Stimulation for Neuropsychiatric Sequelae of Repetitive Traumatic Brain Injury in a Retired NFL Player. J Neuropsychiatry Clin Neurosci 2020; 31:254-263. [PMID: 30945588 DOI: 10.1176/appi.neuropsych.18100230] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The recent advent of individualized resting-state network mapping (RSNM) has revealed substantial interindividual variability in anatomical localization of brain networks identified by using resting-state functional MRI (rsfMRI). RSNM enables personalized targeting of focal neuromodulation techniques such as repetitive transcranial magnetic stimulation (rTMS). rTMS is believed to exert antidepressant efficacy by modulating connectivity between the stimulation site, the default mode network (DMN), and the subgenual anterior cingulate cortex (sgACC). Personalized rTMS may be particularly useful after repetitive traumatic brain injury (TBI), which is associated with neurodegenerative tauopathy in medial temporal limbic structures. These degenerative changes are believed to be related to treatment-resistant neurobehavioral disturbances observed in many retired athletes. METHODS The authors describe a case in which RSNM was successfully used to target rTMS to treat these neuropsychiatric disturbances in a retired NFL defensive lineman whose symptoms were not responsive to conventional treatments. RSNM was used to identify left-right dorsolateral prefrontal rTMS targets with maximal difference between dorsal attention network and DMN correlations. These targets were spatially distinct from those identified by prior methods. Twenty sessions of left-sided excitatory and right-sided inhibitory rTMS were administered at these targets. RESULTS Treatment led to improvement in Montgomery-Åsberg Depression Rating Scale (72%), cognitive testing, and headache scales scores. Compared with healthy individuals and subjects with TBI-associated depression, baseline rsfMRI revealed substantially elevated DMN connectivity with the medial temporal lobe (MTL). Serial rsfMRI scans revealed gradual improvement in MTL-DMN connectivity and stimulation site connectivity with sgACC. CONCLUSIONS These results highlight the possibility of individualized neuromodulation and biomarker-based monitoring for neuropsychiatric sequelae of repetitive TBI.
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Affiliation(s)
- Shan H Siddiqi
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - Nicholas T Trapp
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - Pashtun Shahim
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - Carl D Hacker
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - Timothy O Laumann
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - Sridhar Kandala
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - Alexandre R Carter
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
| | - David L Brody
- The Departments of Psychiatry, Neurology, and Neurosurgery, Washington University School of Medicine, St. Louis (Siddiqi, Trapp, Laumann, Kandala, Shahim, Carter, Brody, Hacker); and Department of Neurology, Harvard Medical School, McLean Hospital, Boston (Siddiqi); and the Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md. (Siddiqi, Shahim); and Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, Iowa (Trapp)
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Siddiqi SH, Trapp NT, Hacker CD, Laumann TO, Kandala S, Hong X, Trillo L, Shahim P, Leuthardt EC, Carter AR, Brody DL. Abstract #156: Functional connectivity changes with targeted rTMS of the dorsal attention network in TBI-associated depression. Brain Stimul 2019. [DOI: 10.1016/j.brs.2018.12.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Siddiqi SH, Trapp NT, Hacker CD, Laumann TO, Kandala S, Hong X, Trillo L, Shahim P, Leuthardt EC, Carter AR, Brody DL. Repetitive Transcranial Magnetic Stimulation with Resting-State Network Targeting for Treatment-Resistant Depression in Traumatic Brain Injury: A Randomized, Controlled, Double-Blinded Pilot Study. J Neurotrauma 2019; 36:1361-1374. [PMID: 30381997 DOI: 10.1089/neu.2018.5889] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Repetitive transcranial magnetic stimulation (rTMS) has demonstrated antidepressant efficacy but has limited evidence in depression associated with traumatic brain injury (TBI). Here, we investigate the use of rTMS targeted with individualized resting-state network mapping (RSNM) of dorsal attention network (DAN) and default mode network (DMN) in subjects with treatment-resistant depression associated with concussive or moderate TBI. The planned sample size was 50 with first interim analysis planned at 20, but only 15 were enrolled before the study was terminated for logistical reasons. Subjects were randomized to 20 sessions of bilateral rTMS (4000 left-sided excitatory pulses, 1000 right-sided inhibitory pulses) or sham. Treatment was targeted to the dorsolateral prefrontal cluster with maximal difference between DAN and DMN correlations based on resting-state functional magnetic resonance imaging with individualized RSNM. Mean improvement in the primary outcome, Montgomery-Asberg Depression Rating Scale (MADRS), was 56% ± 14% (n = 9) with active treatment and 27% ± 25% (n = 5) with sham (Cohen's d = 1.43). One subject randomized to sham withdrew before starting treatment. There were no seizures or other significant adverse events. MADRS improvement was inversely correlated with functional connectivity between the right-sided stimulation site and the subgenual anterior cingulate cortex (sgACC; r = -0.68, 95% confidence interval 0.03-0.925). Active treatment led to increased sgACC-DMN connectivity (d = 1.55) and increased sgACC anti-correlation with the left- and right-sided stimulation sites (d = -1.26 and -0.69, respectively). This pilot study provides evidence that RSNM-targeted rTMS is feasible in TBI patients with depression. Given the dearth of existing evidence-based treatments for depression in this patient population, these preliminarily encouraging results indicate that larger controlled trials are warranted.
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Affiliation(s)
- Shan H Siddiqi
- 1 Department of Neurology, McLean Hospital, Belmont, Massachusetts.,2 Center for Neuroscience and Regenerative Medicine, National Institutes of Health/Uniformed Services University of Health Sciences Traumatic Brain Injury Research Group, Bethesda, Maryland.,3 Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri
| | - Nicholas T Trapp
- 6 Department of Psychiatry, University of Iowa Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Carl D Hacker
- 4 Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Timothy O Laumann
- 3 Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri
| | - Sridhar Kandala
- 3 Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri
| | - Xin Hong
- 5 Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Ludwig Trillo
- 3 Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri
| | - Pashtun Shahim
- 2 Center for Neuroscience and Regenerative Medicine, National Institutes of Health/Uniformed Services University of Health Sciences Traumatic Brain Injury Research Group, Bethesda, Maryland
| | - Eric C Leuthardt
- 4 Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Alexandre R Carter
- 5 Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - David L Brody
- 2 Center for Neuroscience and Regenerative Medicine, National Institutes of Health/Uniformed Services University of Health Sciences Traumatic Brain Injury Research Group, Bethesda, Maryland.,5 Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
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Boyd LA, Hayward KS, Ward NS, Stinear CM, Rosso C, Fisher RJ, Carter AR, Leff AP, Copland DA, Carey LM, Cohen LG, Basso DM, Maguire JM, Cramer SC. Biomarkers of Stroke Recovery: Consensus-Based Core Recommendations from the Stroke Recovery and Rehabilitation Roundtable. Neurorehabil Neural Repair 2018; 31:864-876. [PMID: 29233071 DOI: 10.1177/1545968317732680] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The most difficult clinical questions in stroke rehabilitation are "What is this patient's potential for recovery?" and "What is the best rehabilitation strategy for this person, given her/his clinical profile?" Without answers to these questions, clinicians struggle to make decisions regarding the content and focus of therapy, and researchers design studies that inadvertently mix participants who have a high likelihood of responding with those who do not. Developing and implementing biomarkers that distinguish patient subgroups will help address these issues and unravel the factors important to the recovery process. The goal of the present paper is to provide a consensus statement regarding the current state of the evidence for stroke recovery biomarkers. Biomarkers of motor, somatosensory, cognitive and language domains across the recovery timeline post-stroke are considered; with focus on brain structure and function, and exclusion of blood markers and genetics. We provide evidence for biomarkers that are considered ready to be included in clinical trials, as well as others that are promising but not ready and so represent a developmental priority. We conclude with an example that illustrates the utility of biomarkers in recovery and rehabilitation research, demonstrating how the inclusion of a biomarker may enhance future clinical trials. In this way, we propose a way forward for when and where we can include biomarkers to advance the efficacy of the practice of, and research into, rehabilitation and recovery after stroke.
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Affiliation(s)
- Lara A Boyd
- 1 Department of Physical Therapy & the Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Kathryn S Hayward
- 2 Department of Physical Therapy, University of British Columbia, Vancouver, Canada; Stroke Division, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia
| | - Nick S Ward
- 3 Sobell Department of Motor Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
| | - Cathy M Stinear
- 4 Department of Medicine and Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Charlotte Rosso
- 5 Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, France; AP-HP, Stroke Unit, Pitié-Salpêtrière Hospital, France
| | - Rebecca J Fisher
- 6 Division of Rehabilitation & Ageing, University of Nottingham, Nottingham, UK
| | - Alexandre R Carter
- 7 Department of Neurology, Washington University in Saint Louis, St Louis, MO, USA
| | - Alex P Leff
- 8 Department of Brain Repair and Rehabilitation, Institute of Neurology & Institute of Cognitive Neuroscience, University College London, Queens Square, London, UK
| | - David A Copland
- 9 School of Health & Rehabilitation Sciences, University of Queensland, Brisbane, Australia; and University of Queensland Centre for Clinical Research, Brisbane, Australia
| | - Leeanne M Carey
- 10 School of Allied Health, College of Science, Health and Engineering, La Trobe, University, Bundoora, Australia; and Neurorehabilitation and Recovery, Stroke Division, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia
| | - Leonardo G Cohen
- 11 Human Cortical Physiology and Neurorehabilitation Section, NINDS, NIH, Bethesda, MD, USA
| | - D Michele Basso
- 12 School of Health and Rehabilitation Sciences, The Ohio State University, Columbus, OH, USA
| | - Jane M Maguire
- 13 Faculty of Health, University of Technology Sydney, Ultimo, Sydney, Australia
| | - Steven C Cramer
- 14 University of California, Irvine, CA, USA; Depts. Neurology, Anatomy & Neurobiology, and Physical Medicine & Rehabilitation, Irvine, CA, USA
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Siddiqi SH, Trapp NT, Laumann TO, Hacker CD, Kandala S, Shahim P, Carter AR, Brody DL. Efficacy and neural network changes with fMRI-targeted rTMS for neuropsychiatric sequelae of repetitive head trauma in a retired NFL player. Brain Stimul 2018. [DOI: 10.1016/j.brs.2018.01.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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12
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Boyd LA, Hayward KS, Ward NS, Stinear CM, Rosso C, Fisher RJ, Carter AR, Leff AP, Copland DA, Carey LM, Cohen LG, Basso DM, Maguire JM, Cramer SC. Biomarkers of stroke recovery: Consensus-based core recommendations from the Stroke Recovery and Rehabilitation Roundtable. Int J Stroke 2018; 12:480-493. [PMID: 28697711 DOI: 10.1177/1747493017714176] [Citation(s) in RCA: 219] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The most difficult clinical questions in stroke rehabilitation are "What is this patient's potential for recovery?" and "What is the best rehabilitation strategy for this person, given her/his clinical profile?" Without answers to these questions, clinicians struggle to make decisions regarding the content and focus of therapy, and researchers design studies that inadvertently mix participants who have a high likelihood of responding with those who do not. Developing and implementing biomarkers that distinguish patient subgroups will help address these issues and unravel the factors important to the recovery process. The goal of the present paper is to provide a consensus statement regarding the current state of the evidence for stroke recovery biomarkers. Biomarkers of motor, somatosensory, cognitive and language domains across the recovery timeline post-stroke are considered; with focus on brain structure and function, and exclusion of blood markers and genetics. We provide evidence for biomarkers that are considered ready to be included in clinical trials, as well as others that are promising but not ready and so represent a developmental priority. We conclude with an example that illustrates the utility of biomarkers in recovery and rehabilitation research, demonstrating how the inclusion of a biomarker may enhance future clinical trials. In this way, we propose a way forward for when and where we can include biomarkers to advance the efficacy of the practice of, and research into, rehabilitation and recovery after stroke.
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Affiliation(s)
- Lara A Boyd
- 1 Department of Physical Therapy & the Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Kathryn S Hayward
- 2 Department of Physical Therapy, University of British Columbia, Vancouver, Canada; Stroke Division, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia
| | - Nick S Ward
- 3 Sobell Department of Motor Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
| | - Cathy M Stinear
- 4 Department of Medicine and Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Charlotte Rosso
- 5 Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.,6 AP-HP, Urgences Cérébro-Vasculaires, Hôpital Pitié-Salpêtrière, Paris, France
| | - Rebecca J Fisher
- 7 Division of Rehabilitation & Ageing, University of Nottingham, Nottingham, UK
| | - Alexandre R Carter
- 8 Department of Neurology, Washington University in Saint Louis, St Louis, MO, USA
| | - Alex P Leff
- 9 Department of Brain Repair and Rehabilitation, Institute of Neurology & Institute of Cognitive Neuroscience, University College London, Queens Square, London, UK
| | - David A Copland
- 10 School of Health & Rehabilitation Sciences, University of Queensland, Brisbane, Australia; and University of Queensland Centre for Clinical Research, Brisbane, Australia
| | - Leeanne M Carey
- 11 School of Allied Health, College of Science, Health and Engineering, La Trobe, University, Bundoora, Australia; and Neurorehabilitation and Recovery, Stroke Division, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia
| | - Leonardo G Cohen
- 12 Human Cortical Physiology and Neurorehabilitation Section, NINDS, NIH, Bethesda, MD, USA
| | - D Michele Basso
- 13 School of Health and Rehabilitation Sciences, The Ohio State University, Columbus, OH, USA
| | - Jane M Maguire
- 14 Faculty of Health, University of Technology, Ultimo, Sydney, Australia
| | - Steven C Cramer
- 15 University of California, Irvine, CA, USA; Depts. Neurology, Anatomy & Neurobiology, and Physical Medicine & Rehabilitation, Irvine, CA, USA
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Carter AR, France NE, Lewis BW, Shaw DG. Cholesterol ester storage disease. Radiological features. Pediatr Radiol 2005; 2:135-6. [PMID: 15822337 DOI: 10.1007/bf01314945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Neurotrophins were initially identified as critical regulators of neuronal survival. However, these factors have many additional functions. In the developing cerebellum the roles of the neurotrophins BDNF and NT3 include a surprising effect on patterning, as revealed by changes in foliation in neurotrophin-deficient mice. Here we examine the potential role of p75NTR in cerebellar development and patterning. We show that p75NTR is expressed at highest levels in the region of the cerebellum where foliation is altered in BDNF and NT3 mutants. Although the cerebellar phenotype of p75NTR mutant animals is indistinguishable from wild type, mutation of p75NTR in BDNF heterozygotes results in defects in foliation and in Purkinje cell morphologic development. Taken together, these data suggest that p75NTR activity is critical for cerebellar development under pathologic circumstances where neurotrophin levels are reduced.
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Affiliation(s)
- Alexandre R Carter
- Department of Neurobiology, Harvard Medical School, and Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
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Dubinsky B, Vaidya AH, Rosenthal DI, Hochman C, Crooke JJ, DeLuca S, DeVine A, Cheo-Isaacs CT, Carter AR, Jordan AD, Reitz AB, Shank RP. 5-ethoxymethyl-7-fluoro-3-oxo-1,2,3,5-tetrahydrobenzo[4,5]imidazo[1,2a]pyridine-4-N-(2-fluorophenyl)carboxamide (RWJ-51204), a new nonbenzodiazepine anxiolytic. J Pharmacol Exp Ther 2002; 303:777-90. [PMID: 12388665 DOI: 10.1124/jpet.102.036954] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
5-ethoxymethyl-7-fluoro-3-oxo-1,2,3,5-tetrahydrobenzo[4,5] imidazo[1,2a]pyridine-4-N-(2-fluorophenyl)carboxamide) (RWJ-51204) binds selectively and with high affinity (K(i) = 0.2-2 nM) to the benzodiazepine site on GABA(A) receptors. Considering the GABA shift, the intrinsic modulatory activity of RWJ-51204 is lower than that of full agonist anxiolytics (lorazepam, diazepam, alprazolam, and clonazepam) but similar to partial agonists (bretazenil, abecarnil, panadiplon, and imidazenil). RWJ-51204 was orally active in anxiolytic efficacy tests; pentylenetetrazole induced seizure inhibition in mice (ED(50) = 0.04 mg/kg), Vogel conflict in rats (ED(50) = 0.36 mg/kg), elevated plus-maze in rats (minimal effective dose = 0.1 mg/kg), and conflict in squirrel monkeys (ED(50) = 0.49 mg/kg). RWJ-51204 attenuated chlordiazepoxide-induced motor impairment in mice. Usually, RWJ-51204 was more potent than reference anxiolytics in rodent efficacy tests but less potent in monkey conflict. Usually, the slope of the dose-response lines for RWJ-51204 was more shallow than the full agonist anxiolytics but steeper than partial agonists in efficacy tests but typically shallow in tests for central nervous system side effects. In monkeys only mild or moderate sedation was observed at doses equivalent to 20 or 40 times the anxiolytic ED(50). RWJ-51204 fits into the partial agonist class of GABA(A) receptor modulators. In conclusion, RWJ-51204 exhibits a profile in in vitro experiments and in animal models, in mice and monkeys (but not in rats), suggesting that it has a profile of anxiolytic activity associated with less sedation, motor impairment, or muscle relaxation than currently available GABA(A) receptor modulators, i.e., the benzodiazepines.
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Affiliation(s)
- Barry Dubinsky
- Johnson & Johnson Pharmaceutical Research and Development, L.L.C., Welsh & McKean Roads, Spring House, PA 19477-0776, USA.
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Borghesani PR, Peyrin JM, Klein R, Rubin J, Carter AR, Schwartz PM, Luster A, Corfas G, Segal RA. BDNF stimulates migration of cerebellar granule cells. Development 2002; 129:1435-42. [PMID: 11880352 DOI: 10.1242/dev.129.6.1435] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
During development of the nervous system, neural progenitors arise in proliferative zones, then exit the cell cycle and migrate away from these zones. Here we show that migration of cerebellar granule cells out of their proliferative zone, the external granule cell layer (EGL), is impaired in Bdnf–/– mice. The reason for impaired migration is that BDNF directly and acutely stimulates granule cell migration. Purified Bdnf–/– granule cells show defects in initiation of migration along glial fibers and in Boyden chamber assays. This phenotype can be rescued by exogenous BDNF. Using time-lapse video microscopy we find that BDNF is acutely motogenic as it stimulates migration of individual granule cells immediately after addition. The stimulation of migration reflects both a chemokinetic and chemotactic effect of BDNF. Collectively, these data demonstrate that BDNF is directly motogenic for granule cells and provides a directional cue promoting migration from the EGL to the internal granule cell layer (IGL).
Movies available on-line
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Affiliation(s)
- Paul R Borghesani
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA
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Carter AR, Chen C, Schwartz PM, Segal RA. Brain-derived neurotrophic factor modulates cerebellar plasticity and synaptic ultrastructure. J Neurosci 2002; 22:1316-27. [PMID: 11850459 PMCID: PMC6757568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Neurotrophins are key regulators of neuronal survival and function. Here we show that TrkB, the receptor for brain-derived neurotrophic factor (BDNF), is located at parallel fiber to Purkinje cell (PF/PC) synapses of the cerebellum. To determine the effects of TrkB receptor activation on synapse formation and function, we examined the parallel fiber to Purkinje cell synapses of mice with a targeted deletion of the BDNF gene. Although Purkinje cell dendrites are abnormal in BDNF -/- mice, PF/PC synapses are still able to form. Immunohistochemical analysis of mutant animals revealed the formation of numerous PF/PC synapses with the appropriate apposition of presynaptic and postsynaptic proteins. These synapses are functional, and no differences were detected in the waveform of evoked EPSCs, the amplitude of spontaneous mini-EPSCs, or the response to prolonged 10 Hz stimulus trains. However, paired-pulse facilitation, a form of short-term plasticity, is significantly decreased in BDNF -/- mice. Detailed ultrastructural analysis of the presynaptic terminals demonstrated that this change in synaptic function is accompanied by an increase in the total number of synaptic vesicles in mutant mice and a decrease in the proportion of vesicles that are docked. These data suggest that BDNF regulates both the mechanisms that underlie short-term synaptic plasticity and the steady-state relationship between different vesicle pools within the terminal.
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Affiliation(s)
- Alexandre R Carter
- Department of Pediatric Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
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Abstract
Pathophysiological features of both primary aldosteronism and pseudohyperaldosteronism are hyperactive amiloride-sensitive epithelial Na(+) channels (ENaC) and refractory hypertension. Peripheral blood lymphocytes express ENaC, which functions and is regulated similarly to ENaC expressed by renal principal cells. Thus it was hypothesized that individuals with either of these hypertensive etiologies could be identified by assessment of the function and regulation of peripheral blood lymphocyte ENaC, by whole cell patch clamp. We also tested the hypothesis that specific inhibition of hyperactive ENaC with amiloride could ameliorate the hypertension. To test these hypotheses, we solicited blood samples from normotensive, controlled hypertensive, and refractory hypertensive individuals. Lymphocytes were examined electrophysiologically to determine whether ENaC was hyperactive. All positive findings were from refractory hypertensive individuals. Nine refractory hypertensive patients had amiloride added to their hypertensive therapy. Amiloride normalized the blood pressure of four subjects. These individuals all had hyperactive ENaC. Amiloride had no effect on individuals with normal ENaC. These findings suggest that whole-cell patch clamp of peripheral blood lymphocytes can be used to identify accurately and rapidly hypertensive individuals who will respond to amiloride therapy.
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Affiliation(s)
- A R Carter
- Vascular Biology and Hypertension Program, Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Herman AE, Galaburda AM, Fitch RH, Carter AR, Rosen GD. Cerebral microgyria, thalamic cell size and auditory temporal processing in male and female rats. Cereb Cortex 1997; 7:453-64. [PMID: 9261574 DOI: 10.1093/cercor/7.5.453] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Induction of microgyria by freezing injury to the developing somatosensory cortex of neonatal rats causes a defect in fast auditory processing in males, but not in females. It was speculated that early damage to the cortex has sexually dimorphic cascading effects on other brain regions mediating auditory processing, which can lead to the observed behavioral deficits. In the current series of experiments, bilateral microgyri were induced by placement of a freezing probe on the skulls of newborn male and female rats, and these animals were tested in adulthood for auditory temporal processing. Control animals received sham surgery. The brains from these animals were embedded in celloidin, cut in the coronal plane and the following morphometric measures assessed: microgyric volume, medial geniculate nucleus (MGN) volume, cell number, and cell size, and, as a control, dorsal lateral geniculate nucleus (dLGN) volume, cell number and cell size. There were no sex differences in the cortical pathology of lesioned animals. However, microgyric males had more small and fewer large neurons in the MGN than their sham-operated counterparts, whereas there was no difference between lesioned and sham-operated females. There was no effect on dLGN cell size distribution in either sex. Microgyric males were significantly impaired in fast auditory temporal processing when compared to control males, whereas lesioned females exhibited no behavioral deficits. These results suggest that early injury to the cerebral cortex may have different effects on specific thalamic nuclei in males and females, with corresponding differences in behavioral effects.
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Affiliation(s)
- A E Herman
- Dyslexia Research Laboratory, Beth Israel Deaconess Medical Center, Beth Israel Hospital, Boston, MA 02215, USA
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Abstract
In a prospective study ultrasound was compared to palpation in 41 instances in which a testis was not present in the scrotum. A testis was palpable in 20 of these instances and not palpated in 21. Of 20 palpable undescended testes 14 (70 per cent) were identified by ultrasound. Of the 21 instances in which a testis was not palpated 3 intra-abdominal and 5 inguinal testes were identified at exploration. One of these organs (an inguinal testis) was identified by ultrasound. Two false positive sonograms in which a gubernacular structure mimicked an undescended testis occurred. Sonography cannot satisfactorily stand alone as a screening modality in the management of the undescended testis.
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Abstract
Three cases of cavernous transformation of the portal vein are presented, which emphasize the value of duplex Doppler sonography in the recognition of abnormal vascular structures. In all three cases, cavernous transformation was unsuspected; in two, the initial sonographic or CT examinations were interpreted incorrectly. These cases suggest that the combination of characteristic pulsed-Doppler waveforms and the real-time appearance of cavernous transformation is virtually diagnostic.
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Abstract
A triangular echogenic area in the upper pole renal parenchyma can be identified at times during routine sonography of the right kidney. Thirty such cases are presented. Occasionally similar echogenic defects in the parenchyma can be seen posteriorly in the lower pole and in the left kidney. These defects in the parenchyma result from normal extensions of the renal sinus of kidneys that have a distinct division of their upper and lower poles. This is due to partial fusion of two embryonic parenchymatous masses called renunculi. The defects in the parenchyma occur at the junction of the renunculi; hence we have termed them junctional parenchymal defects. In order to differentiate them from pathologic conditions, one must identify their characteristic location and demonstrate continuity with the renal sinus.
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Abstract
A series of 92 adult patients undergoing elective cardiac surgery was reviewed to distinguish routine postoperative radiographic alterations from signs of clinically significant complications. Two postoperative complications required decisive clinical intervention: mediastinal hemorrhage (7% of cases) and sternal wound infections (3% of cases). Mediastinal hemorrhage was most often diagnosed by excessive bloody mediastinal tube drainage alone, although progressive mediastinal widening and pleural or apical extrapleural hematomas provided corroborating or, rarely, the sole evidence of mediastinal hemorrhage. Sternal wound infections were most often diagnosed clinically, but increasing pre- and retrosternal gas collections provided radiographic confirmation. Atelectasis was the most common postoperative finding. There were many abnormal gas and soft-tissue collections posteroperatively that were notable for their lack of clinical importance. Serial postoperative films were necessary to demonstrate the progression of radiographic findings which indicate the two important postoperative complications.
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Abstract
Two patients with rheumatoid arthritis are described, who developed very large bone cysts or geodes adjacent to the knee-joint. The existence of cysts adjacent to joints involved by rheumatoid arthritis is well recognised, but the occurrence of very large cysts is unusual and may present diagnostic difficulties. Possible aetiological factors are discussed.
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Krikler DM, Zilberg B, Carter AR. Upper limb-cardiovascular syndrome. S Afr Med J 1969; 43:897-900. [PMID: 5821602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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