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Yale AR, Kim E, Gutierrez B, Hanamoto JN, Lav NS, Nourse JL, Salvatus M, Hunt RF, Monuki ES, Flanagan LA. Regulation of neural stem cell differentiation and brain development by MGAT5-mediated N-glycosylation. Stem Cell Reports 2023:S2213-6711(23)00141-8. [PMID: 37172586 DOI: 10.1016/j.stemcr.2023.04.007] [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] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 05/15/2023] Open
Abstract
Undifferentiated neural stem and progenitor cells (NSPCs) encounter extracellular signals that bind plasma membrane proteins and influence differentiation. Membrane proteins are regulated by N-linked glycosylation, making it possible that glycosylation plays a critical role in cell differentiation. We assessed enzymes that control N-glycosylation in NSPCs and found that loss of the enzyme responsible for generating β1,6-branched N-glycans, N-acetylglucosaminyltransferase V (MGAT5), led to specific changes in NSPC differentiation in vitro and in vivo. Mgat5 homozygous null NSPCs in culture formed more neurons and fewer astrocytes compared with wild-type controls. In the brain cerebral cortex, loss of MGAT5 caused accelerated neuronal differentiation. Rapid neuronal differentiation led to depletion of cells in the NSPC niche, resulting in a shift in cortical neuron layers in Mgat5 null mice. Glycosylation enzyme MGAT5 plays a critical and previously unrecognized role in cell differentiation and early brain development.
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Affiliation(s)
- Andrew R Yale
- Department of Anatomy & Neurobiology, University of California Irvine, Irvine, CA 92697, USA; Department of Neurology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Estelle Kim
- Department of Neurology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Brenda Gutierrez
- Department of Anatomy & Neurobiology, University of California Irvine, Irvine, CA 92697, USA; Department of Neurology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - J Nicole Hanamoto
- Department of Neurology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Nicole S Lav
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Jamison L Nourse
- Department of Neurology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Marc Salvatus
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Edwin S Monuki
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Department of Pathology & Laboratory Medicine, University of California Irvine, Irvine, CA 92697, USA
| | - Lisa A Flanagan
- Department of Anatomy & Neurobiology, University of California Irvine, Irvine, CA 92697, USA; Department of Neurology, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697, USA.
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2
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Haile MT, Khoja S, de Carvalho G, Hunt RF, Chen LY. Conditional deletion of Neurexin-2 alters neuronal network activity in hippocampal circuitries and leads to spontaneous seizures. Transl Psychiatry 2023; 13:97. [PMID: 36941261 PMCID: PMC10027846 DOI: 10.1038/s41398-023-02394-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 02/27/2023] [Accepted: 03/02/2023] [Indexed: 03/23/2023] Open
Abstract
Neurexins (Nrxns) have been extensively studied for their role in synapse organization and have been linked to many neuropsychiatric disorders, including autism spectrum disorder (ASD), and epilepsy. However, no studies have provided direct evidence that Nrxns may be the key regulator in the shared pathogenesis of these conditions largely due to complexities among Nrxns and their non-canonical functions in different synapses. Recent studies identified NRXN2 mutations in ASD and epilepsy, but little is known about Nrxn2's role in a circuit-specific manner. Here, we report that conditional deletion of Nrxn2 from the hippocampus and cortex (Nrxn2 cKO) results in behavioral abnormalities, including reduced social preference and increased nestlet shredding behavior. Electrophysiological recordings identified an overall increase in hippocampal CA3→CA1 network activity in Nrxn2 cKO mice. Using intracranial electroencephalogram recordings, we observed unprovoked spontaneous reoccurring electrographic and behavioral seizures in Nrxn2 cKO mice. This study provides the first evidence that conditional deletion of Nrxn2 induces increased network activity that manifests into spontaneous recurrent seizures and behavioral impairments.
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Affiliation(s)
- Mulatwa T Haile
- Department of Anatomy & Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Sheraz Khoja
- Department of Anatomy & Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Gregory de Carvalho
- Department of Anatomy & Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Lulu Y Chen
- Department of Anatomy & Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA.
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3
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Frankowski JC, Tierno A, Pavani S, Cao Q, Lyon DC, Hunt RF. Brain-wide reconstruction of inhibitory circuits after traumatic brain injury. Nat Commun 2022; 13:3417. [PMID: 35701434 PMCID: PMC9197933 DOI: 10.1038/s41467-022-31072-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 05/31/2022] [Indexed: 11/09/2022] Open
Abstract
Despite the fundamental importance of understanding the brain's wiring diagram, our knowledge of how neuronal connectivity is rewired by traumatic brain injury remains remarkably incomplete. Here we use cellular resolution whole-brain imaging to generate brain-wide maps of the input to inhibitory neurons in a mouse model of traumatic brain injury. We find that somatostatin interneurons are converted into hyperconnected hubs in multiple brain regions, with rich local network connections but diminished long-range inputs, even at areas not directly damaged. The loss of long-range input does not correlate with cell loss in distant brain regions. Interneurons transplanted into the injury site receive orthotopic local and long-range input, suggesting the machinery for establishing distant connections remains intact even after a severe injury. Our results uncover a potential strategy to sustain and optimize inhibition after traumatic brain injury that involves spatial reorganization of the direct inputs to inhibitory neurons across the brain.
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Affiliation(s)
- Jan C Frankowski
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Alexa Tierno
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA.
| | - Shreya Pavani
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Quincy Cao
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA
| | - David C Lyon
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA. .,Epilepsy Research Center, University of California, Irvine, CA, 92697, USA. .,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA, 92697, USA. .,Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, CA, 92697, USA. .,Center for Neural Circuit Mapping, University of California, Irvine, Irvine, CA, 92697, USA.
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4
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Frankowski JC, Foik AT, Tierno A, Machhor JR, Lyon DC, Hunt RF. Traumatic brain injury to primary visual cortex produces long-lasting circuit dysfunction. Commun Biol 2021; 4:1297. [PMID: 34789835 PMCID: PMC8599505 DOI: 10.1038/s42003-021-02808-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 10/25/2021] [Indexed: 01/20/2023] Open
Abstract
Primary sensory areas of the mammalian neocortex have a remarkable degree of plasticity, allowing neural circuits to adapt to dynamic environments. However, little is known about the effects of traumatic brain injury on visual circuit function. Here we used anatomy and in vivo electrophysiological recordings in adult mice to quantify neuron responses to visual stimuli two weeks and three months after mild controlled cortical impact injury to primary visual cortex (V1). We found that, although V1 remained largely intact in brain-injured mice, there was ~35% reduction in the number of neurons that affected inhibitory cells more broadly than excitatory neurons. V1 neurons showed dramatically reduced activity, impaired responses to visual stimuli and weaker size selectivity and orientation tuning in vivo. Our results show a single, mild contusion injury produces profound and long-lasting impairments in the way V1 neurons encode visual input. These findings provide initial insight into cortical circuit dysfunction following central visual system neurotrauma.
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Affiliation(s)
- Jan C. Frankowski
- grid.266093.80000 0001 0668 7243Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697 USA
| | - Andrzej T. Foik
- grid.413454.30000 0001 1958 0162Ophthalmic Biology Group, International Centre for Translational Eye Research, Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Alexa Tierno
- grid.266093.80000 0001 0668 7243Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697 USA
| | - Jiana R. Machhor
- grid.266093.80000 0001 0668 7243Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697 USA
| | - David C. Lyon
- grid.266093.80000 0001 0668 7243Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697 USA
| | - Robert F. Hunt
- grid.266093.80000 0001 0668 7243Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697 USA
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5
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Abstract
Repair of the traumatically injured brain has been envisioned for decades, but regenerating new neurons at the site of brain injury has been challenging. We show GABAergic progenitors, derived from the embryonic medial ganglionic eminence, migrate long distances following transplantation into the hippocampus of adult mice with traumatic brain injury, functionally integrate as mature inhibitory interneurons and restore post-traumatic decreases in synaptic inhibition. Grafted animals had improvements in memory precision that were reversed by chemogenetic silencing of the transplanted neurons and a long-lasting reduction in spontaneous seizures. Our results reveal a striking ability of transplanted interneurons for incorporating into injured brain circuits, and this approach is a powerful therapeutic strategy for correcting post-traumatic memory and seizure disorders.
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Affiliation(s)
- Bingyao Zhu
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Jisu Eom
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California, Irvine, CA, 92697, USA. .,Center for the Neurobiology of Learning and Memory, University of California, Irvine, CA, 92697, USA. .,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA, 92697, USA.
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6
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Lim BC, Hunt RF. Epilepsy Therapy Goes Viral. Epilepsy Curr 2019; 19:328-329. [PMID: 31462070 PMCID: PMC6864564 DOI: 10.1177/1535759719870506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Epilepsy Gene Therapy Using an Engineered Potassium Channel Snowball A, Chabrol E, Wykes RC, Shekh-Ahmad T, Cornford JH, Lieb A, Hughes MP, Massaro G, Rahim AA, Hashemi KS, Kullmann DM, Walker MC, Schorge S. J Neurosci. 2019;39(16):3159-3169. doi:10.1523/JNEUROSCI.1143-18.2019 Refractory focal epilepsy is a devastating disease for which there is frequently no effective treatment. Gene therapy represents a promising alternative, but treating epilepsy in this way involves irreversible changes to brain tissue, so vector design must be carefully optimized to guarantee safety without compromising efficacy. We set out to develop an epilepsy gene therapy vector optimized for clinical translation. The gene encoding the voltage-gated potassium channel Kv1.1, KCNA1, was codon optimized for human expression and mutated to accelerate the recovery of the channels from inactivation. For improved safety, this engineered potassium channel (EKC) gene was packaged into a nonintegrating lentiviral vector under the control of a cell type-specific CAMK2A promoter. In a blinded, randomized, placebo-controlled preclinical trial, the EKC lentivector robustly reduced seizure frequency in a male rat model of focal neocortical epilepsy characterized by discrete spontaneous seizures. When packaged into an adeno-associated viral vector (AAV2/9), the EKC gene was also effective at suppressing seizures in a male rat model of temporal lobe epilepsy. This demonstration of efficacy in a clinically relevant setting, combined with the improved safety conferred by cell type–specific expression and integration-deficient delivery, identifies EKC gene therapy as being ready for clinical translation in the treatment of refractory focal epilepsy.
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7
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Kim YJ, Khoshkhoo S, Frankowski JC, Zhu B, Abbasi S, Lee S, Wu YE, Hunt RF. Chd2 Is Necessary for Neural Circuit Development and Long-Term Memory. Neuron 2018; 100:1180-1193.e6. [PMID: 30344048 PMCID: PMC6479120 DOI: 10.1016/j.neuron.2018.09.049] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [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: 10/10/2017] [Revised: 07/31/2018] [Accepted: 09/26/2018] [Indexed: 12/18/2022]
Abstract
Considerable evidence suggests loss-of-function mutations in the chromatin remodeler CHD2 contribute to a broad spectrum of human neurodevelopmental disorders. However, it is unknown how CHD2 mutations lead to impaired brain function. Here we report mice with heterozygous mutations in Chd2 exhibit deficits in neuron proliferation and a shift in neuronal excitability that included divergent changes in excitatory and inhibitory synaptic function. Further in vivo experiments show that Chd2+/- mice displayed aberrant cortical rhythmogenesis and severe deficits in long-term memory, consistent with phenotypes observed in humans. We identified broad, age-dependent transcriptional changes in Chd2+/- mice, including alterations in neurogenesis, synaptic transmission, and disease-related genes. Deficits in interneuron density and memory caused by Chd2+/- were reproduced by Chd2 mutation restricted to a subset of inhibitory neurons and corrected by interneuron transplantation. Our results provide initial insight into how Chd2 haploinsufficiency leads to aberrant cortical network function and impaired memory.
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Affiliation(s)
- Young J Kim
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA.
| | - Sattar Khoshkhoo
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA; Department of Neurology, Brigham and Women's Hospital and Massachusetts General Hospital, Harvard University, Boston, MA 02115, USA
| | - Jan C Frankowski
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA
| | - Bingyao Zhu
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA
| | - Saad Abbasi
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA
| | - Sunyoung Lee
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA; Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ye Emily Wu
- Department of Biological Chemistry and Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA.
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8
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Frankowski JC, Kim YJ, Hunt RF. Selective vulnerability of hippocampal interneurons to graded traumatic brain injury. Neurobiol Dis 2018; 129:208-216. [PMID: 30031783 DOI: 10.1016/j.nbd.2018.07.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/26/2018] [Accepted: 07/18/2018] [Indexed: 12/21/2022] Open
Abstract
Traumatic brain injury is a major risk factor for many long-term mental health problems. Although underlying mechanisms likely involve compromised inhibition, little is known about how individual subpopulations of interneurons are affected by neurotrauma. Here we report long-term loss of hippocampal interneurons following controlled cortical impact (CCI) injury in young-adult mice, a model of focal cortical contusion injury in humans. Brain injured mice displayed subfield and cell-type specific decreases in interneurons 30 days after impact depths of 0.5 mm and 1.0 mm, and increasing the depth of impact led to greater cell loss. In general, we found a preferential reduction of interneuron cohorts located in principal cell and polymorph layers, while cell types positioned in the molecular layer appeared well preserved. Our results suggest a dramatic shift of interneuron diversity following contusion injury that may contribute to the pathophysiology of traumatic brain injury.
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Affiliation(s)
- Jan C Frankowski
- Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697, USA
| | - Young J Kim
- Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California, Irvine, CA 92697, USA.
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9
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Dinday MT, Girskis KM, Lee S, Baraban SC, Hunt RF. Publisher Correction: PAFAH1B1 haploinsufficiency disrupts GABA neurons and synaptic E/I balance in the dentate gyrus. Sci Rep 2018; 8:6781. [PMID: 29692423 PMCID: PMC5915572 DOI: 10.1038/s41598-018-24610-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Matthew T Dinday
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Kelly M Girskis
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Sunyoung Lee
- Department of Anatomy & Neurobiology, University of California Irvine, California, USA
| | - Scott C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California Irvine, California, USA.
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10
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Dinday MT, Girskis KM, Lee S, Baraban SC, Hunt RF. PAFAH1B1 haploinsufficiency disrupts GABA neurons and synaptic E/I balance in the dentate gyrus. Sci Rep 2017; 7:8269. [PMID: 28811646 PMCID: PMC5557934 DOI: 10.1038/s41598-017-08809-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/12/2017] [Indexed: 11/18/2022] Open
Abstract
Hemizygous mutations in the human gene encoding platelet-activating factor acetylhydrolase IB subunit alpha (Pafah1b1), also called Lissencephaly-1, can cause classical lissencephaly, a severe malformation of cortical development. Children with this disorder suffer from deficits in neuronal migration, severe intellectual disability, intractable epilepsy and early death. While many of these features can be reproduced in Pafah1b1+/- mice, the impact of Pafah1b1+/- on the function of individual subpopulations of neurons and ultimately brain circuits is largely unknown. Here, we show tangential migration of young GABAergic interneurons into the developing hippocampus is slowed in Pafah1b1+/- mice. Mutant mice had a decreased density of parvalbumin- and somatostatin-positive interneurons in dentate gyrus, but no change in density of calretinin interneurons. Whole-cell patch-clamp recordings revealed increased excitatory and decreased inhibitory synaptic inputs onto granule cells of Pafah1b1+/- mice. Mutant animals developed spontaneous electrographic seizures, as well as long-term deficits in contextual memory. Our findings provide evidence of a dramatic shift in excitability in the dentate gyrus of Pafah1b1+/- mice that may contribute to epilepsy or cognitive impairments associated with lissencephaly.
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Affiliation(s)
- Matthew T Dinday
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Kelly M Girskis
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Sunyoung Lee
- Department of Anatomy & Neurobiology, University of California Irvine, California, USA
| | - Scott C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California Irvine, California, USA.
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11
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Abstract
Stem-cell therapy has extraordinary potential to address critical, unmet needs in the treatment of human disease. One particularly promising approach for the treatment of epilepsy is to increase inhibition in areas of the epileptic brain by grafting new inhibitory cortical interneurons. When grafted from embryos, young γ-aminobutyric acid (GABA)ergic precursors disperse, functionally mature into host brain circuits as local-circuit interneurons, and can stop seizures in both genetic and acquired forms of the disease. These features make interneuron cell transplantation an attractive new approach for the treatment of intractable epilepsies, as well as other brain disorders that involve increased risk for epilepsy as a comorbidity. Here, we review recent efforts to isolate and transplant cortical interneuron precursors derived from embryonic mouse and human cell sources. We also discuss some of the important challenges that must be addressed before stem-cell-based treatment for human epilepsy is realized.
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Affiliation(s)
- Robert F Hunt
- Department of Anatomy & Neurobiology, University of California Irvine, Irvine, California 92697
| | - Scott C Baraban
- Department of Anatomy & Neurobiology, University of California Irvine, Irvine, California 92697
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12
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Stanco A, Pla R, Vogt D, Chen Y, Mandal S, Walker J, Hunt RF, Lindtner S, Erdman CA, Pieper AA, Hamilton SP, Xu D, Baraban SC, Rubenstein JLR. NPAS1 represses the generation of specific subtypes of cortical interneurons. Neuron 2014; 84:940-53. [PMID: 25467980 DOI: 10.1016/j.neuron.2014.10.040] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2014] [Indexed: 11/29/2022]
Abstract
Little is known about genetic mechanisms that regulate the ratio of cortical excitatory and inhibitory neurons. We show that NPAS1 and NPAS3 transcription factors (TFs) are expressed in progenitor domains of the mouse basal ganglia (subpallium, MGE, and CGE). NPAS1(-/-) mutants had increased proliferation, ERK signaling, and expression of Arx in the MGE and CGE. NPAS1(-/-) mutants also had increased neocortical inhibition (sIPSC and mIPSC) and generated an excess of somatostatin(+) (SST) (MGE-derived) and vasoactive intestinal polypeptide(+) (VIP) (CGE-derived) neocortical interneurons, but had a normal density of parvalbumin(+) (PV) (MGE-derived) interneurons. In contrast, NPAS3(-/-) mutants showed decreased proliferation and ERK signaling in progenitors of the ganglionic eminences and had fewer SST(+) and VIP(+) interneurons. NPAS1 repressed activity of an Arx enhancer, and Arx overexpression resulted in increased proliferation of CGE progenitors. These results provide insights into genetic regulation of cortical interneuron numbers and cortical inhibitory tone.
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Affiliation(s)
- Amelia Stanco
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA.
| | - Ramón Pla
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA
| | - Daniel Vogt
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA
| | - Yiran Chen
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Shyamali Mandal
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA
| | - Jamie Walker
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Robert F Hunt
- Department of Neurological Surgery, Neuroscience Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Susan Lindtner
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA
| | - Carolyn A Erdman
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA
| | - Andrew A Pieper
- Department of Psychiatry and Neurology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
| | - Steven P Hamilton
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA
| | - Duan Xu
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Scott C Baraban
- Department of Neurological Surgery, Neuroscience Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John L R Rubenstein
- Department of Psychiatry, Neuroscience Program, and the Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA 94158-2324, USA.
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13
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Vogt D, Hunt RF, Mandal S, Sandberg M, Silberberg SN, Nagasawa T, Yang Z, Baraban SC, Rubenstein JLR. Lhx6 directly regulates Arx and CXCR7 to determine cortical interneuron fate and laminar position. Neuron 2014; 82:350-64. [PMID: 24742460 DOI: 10.1016/j.neuron.2014.02.030] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2014] [Indexed: 12/13/2022]
Abstract
Cortical GABAergic interneurons have essential roles for information processing and their dysfunction is implicated in neuropsychiatric disorders. Transcriptional codes are elucidating mechanisms of interneuron specification in the MGE (a subcortical progenitor zone), which regulate their migration, integration, and function within cortical circuitry. Lhx6, a LIM-homeodomain transcription factor, is essential for specification of MGE-derived somatostatin and parvalbumin interneurons. Here, we demonstrate that some Lhx6⁻/⁻ MGE cells acquire a CGE-like fate. Using an in vivo MGE complementation/transplantation assay, we show that Lhx6-regulated genes Arx and CXCR7 rescue divergent aspects of Lhx6⁻/⁻ cell-fate and laminar mutant phenotypes and provide insight into a neonatal role for CXCR7 in MGE-derived interneuron lamination. Finally, Lhx6 directly binds in vivo to an Arx enhancer and to an intronic CXCR7 enhancer that remains active in mature interneurons. These data define the molecular identity of Lhx6 mutants and introduce technologies to test mechanisms in GABAergic interneuron differentiation.
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Affiliation(s)
- Daniel Vogt
- Department of Psychiatry, Neuroscience Program and the Nina Ireland Laboratory of Developmental Neurobiology, University of California San Francisco, San Francisco, CA 94158, USA.
| | - Robert F Hunt
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Shyamali Mandal
- Department of Psychiatry, Neuroscience Program and the Nina Ireland Laboratory of Developmental Neurobiology, University of California San Francisco, San Francisco, CA 94158, USA; Department of Cancer Biology and Pharmacology University of Illinois, Peoria, IL 61656, USA
| | - Magnus Sandberg
- Department of Psychiatry, Neuroscience Program and the Nina Ireland Laboratory of Developmental Neurobiology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Shanni N Silberberg
- Department of Psychiatry, Neuroscience Program and the Nina Ireland Laboratory of Developmental Neurobiology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Takashi Nagasawa
- Department of Immunology and Hematology, Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Zhengang Yang
- Institutes of Brain Science, Fudan University, Shanghai 200032, China
| | - Scott C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John L R Rubenstein
- Department of Psychiatry, Neuroscience Program and the Nina Ireland Laboratory of Developmental Neurobiology, University of California San Francisco, San Francisco, CA 94158, USA.
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14
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Abstract
Traumatic brain injury (TBI) greatly increases the risk for a number of mental health problems and is one of the most common causes of medically intractable epilepsy in humans. Several models of TBI have been developed to investigate the relationship between trauma, seizures, and epilepsy-related changes in neural circuit function. These studies have shown that the brain initiates immediate neuronal and glial responses following an injury, usually leading to significant cell loss in areas of the injured brain. Over time, long-term changes in the organization of neural circuits, particularly in neocortex and hippocampus, lead to an imbalance between excitatory and inhibitory neurotransmission and increased risk for spontaneous seizures. These include alterations to inhibitory interneurons and formation of new, excessive recurrent excitatory synaptic connectivity. Here, we review in vivo models of TBI as well as key cellular mechanisms of synaptic reorganization associated with post-traumatic epilepsy (PTE). The potential role of inflammation and increased blood-brain barrier permeability in the pathophysiology of PTE is also discussed. A better understanding of mechanisms that promote the generation of epileptic activity versus those that promote compensatory brain repair and functional recovery should aid development of successful new therapies for PTE.
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Affiliation(s)
- Robert F Hunt
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, CA, USA
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15
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Hunt RF, Girskis KM, Rubenstein JL, Alvarez-Buylla A, Baraban SC. GABA progenitors grafted into the adult epileptic brain control seizures and abnormal behavior. Nat Neurosci 2013; 16:692-7. [PMID: 23644485 PMCID: PMC3665733 DOI: 10.1038/nn.3392] [Citation(s) in RCA: 216] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 03/26/2013] [Indexed: 01/16/2023]
Abstract
Impaired GABA-mediated neurotransmission has been implicated in many neurologic diseases, including epilepsy, intellectual disability and psychiatric disorders. We found that inhibitory neuron transplantation into the hippocampus of adult mice with confirmed epilepsy at the time of grafting markedly reduced the occurrence of electrographic seizures and restored behavioral deficits in spatial learning, hyperactivity and the aggressive response to handling. In the recipient brain, GABA progenitors migrated up to 1,500 μm from the injection site, expressed genes and proteins characteristic for interneurons, differentiated into functional inhibitory neurons and received excitatory synaptic input. In contrast with hippocampus, cell grafts into basolateral amygdala rescued the hyperactivity deficit, but did not alter seizure activity or other abnormal behaviors. Our results highlight a critical role for interneurons in epilepsy and suggest that interneuron cell transplantation is a powerful approach to halting seizures and rescuing accompanying deficits in severely epileptic mice.
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Affiliation(s)
- Robert F Hunt
- Epilepsy Research Laboratory, University of California, San Francisco, California, USA.
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16
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Hunt RF, Hortopan GA, Gillespie A, Baraban SC. A novel zebrafish model of hyperthermia-induced seizures reveals a role for TRPV4 channels and NMDA-type glutamate receptors. Exp Neurol 2012; 237:199-206. [PMID: 22735490 DOI: 10.1016/j.expneurol.2012.06.013] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 05/31/2012] [Accepted: 06/16/2012] [Indexed: 12/22/2022]
Abstract
Febrile seizures are the most common seizure type in children under the age of five, but mechanisms underlying seizure generation in vivo remain unclear. Animal models to address this issue primarily focus on immature rodents heated indirectly using a controlled water bath or air blower. Here we describe an in vivo model of hyperthermia-induced seizures in larval zebrafish aged 3 to 7 days post-fertilization (dpf). Bath controlled changes in temperature are rapid and reversible in this model. Acute electrographic seizures following transient hyperthermia showed age-dependence, strain independence, and absence of mortality. Electrographic seizures recorded in the larval zebrafish forebrain were blocked by adding antagonists to the transient receptor potential vanilloid (TRPV4) channel or N-methyl-d-aspartate (NMDA) glutamate receptor to the bathing medium. Application of GABA, GABA re-uptake inhibitors, or TRPV1 antagonist had no effect on hyperthermic seizures. Expression of vanilloid channel and glutamate receptor mRNA was confirmed by quantitative PCR analysis at each developmental stage in larval zebrafish. Taken together, our findings suggest a role of heat-activation of TRPV4 channels and enhanced NMDA receptor-mediated glutamatergic transmission in hyperthermia-induced seizures.
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Affiliation(s)
- Robert F Hunt
- Epilepsy Research Laboratory, Department of Neurological Surgery, Biomedical Graduate Program, University of California San Francisco, San Francisco, CA 94143, USA
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17
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Hunt RF, Haselhorst LA, Schoch KM, Bach EC, Rios-Pilier J, Scheff SW, Saatman KE, Smith BN. Posttraumatic mossy fiber sprouting is related to the degree of cortical damage in three mouse strains. Epilepsy Res 2012; 99:167-70. [PMID: 22047981 PMCID: PMC3290720 DOI: 10.1016/j.eplepsyres.2011.10.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [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] [Received: 03/28/2011] [Revised: 09/16/2011] [Accepted: 10/09/2011] [Indexed: 11/22/2022]
Abstract
Controlled cortical impact injury was used to examine relationships between focal posttraumatic cortical damage and mossy fiber sprouting (MFS) in the dentate gyrus in three mouse strains. Posttraumatic MFS was more robust when cortical injury impinged upon the hippocampus, versus contusions restricted to neocortex, and was qualitatively similar among CD-1, C57BL/6, and FVB/N background strains. Impact parameters influencing injury severity may be critical in reproducing epilepsy-related changes in neurotrauma models.
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Affiliation(s)
- Robert F. Hunt
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Laura A. Haselhorst
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Kathleen M. Schoch
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Eva C. Bach
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
| | | | - Stephen W. Scheff
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington, KY 40536-0298, USA
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536-0298, USA
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Kathryn E. Saatman
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536-0298, USA
| | - Bret N. Smith
- Department of Physiology, University of Kentucky, Lexington, KY 40536-0298, USA
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536-0298, USA
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18
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Hunt RF, Scheff SW, Smith BN. Regionally localized recurrent excitation in the dentate gyrus of a cortical contusion model of posttraumatic epilepsy. J Neurophysiol 2010; 103:1490-500. [PMID: 20089815 DOI: 10.1152/jn.00957.2009] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Posttraumatic epilepsy is a frequent consequence of brain trauma, but relatively little is known about how neuronal circuits are chronically altered after closed head injury. We examined whether local recurrent excitatory synaptic connections form between dentate granule cells in mice 8-12 wk after cortical contusion injury. Mice were monitored for behavioral seizures shortly after brain injury and < or = 10 wk postinjury. Injury-induced seizures were observed in 15% of mice, and spontaneous seizures were observed weeks later in 40% of mice. Timm's staining revealed mossy fiber sprouting into the inner molecular layer of the dorsal dentate gyrus ipsilateral to the injury in 95% of mice but not contralateral to the injury or in uninjured controls. Whole cell patch-clamp recordings were made from granule cells in isolated hippocampal brain slices. Cells in slices with posttraumatic mossy fiber sprouting had an increased excitatory postsynaptic current (EPSC) frequency compared with cells in slices without sprouting from injured and control animals (P < 0.001). When perfused with Mg(2+)-free artificial cerebrospinal fluid containing 100 microM picrotoxin, these cells had spontaneous bursts of EPSCs and action potentials. Focal glutamate photostimulation of the granule cell layer evoked a burst of EPSCs and action potentials indicative of recurrent excitatory connections in granule cells of slices with mossy fiber sprouting. In granule cells of slices without sprouting from injured animals and controls, spontaneous or photostimulation-evoked epileptiform activity was never observed. These results suggest that a new regionally localized excitatory network forms between dentate granule cells near the injury site within weeks after cortical contusion head injury.
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Affiliation(s)
- Robert F Hunt
- Dept. of Physiology, University of Kentucky, Lexington, KY 40536, USA
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19
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Hunt RF, Scheff SW, Smith BN. Posttraumatic epilepsy after controlled cortical impact injury in mice. Exp Neurol 2008; 215:243-52. [PMID: 19013458 DOI: 10.1016/j.expneurol.2008.10.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 10/06/2008] [Accepted: 10/10/2008] [Indexed: 11/28/2022]
Abstract
Many patients develop temporal lobe epilepsy after trauma, but basic mechanisms underlying the development of chronic seizures after head injury remain poorly understood. Using the controlled cortical impact injury model we examined whether mice developed spontaneous seizures after mild (0.5 mm injury depth) or severe (1.0 mm injury depth) brain injury and how subsequent posttraumatic mossy fiber sprouting was associated with excitability in the dentate gyrus 42-71 d after injury. After several weeks, spontaneous behavioral seizures were observed in 20% of mice with mild and 36% of mice with severe injury. Mossy fiber sprouting was typically present in septal slices of the dentate gyrus ipsilateral to the injury, but not in control mice. In slices with mossy fiber sprouting, perforant path stimulation revealed a significant reduction (P<0.01) in paired-pulse ratios in dentate granule cells at 20 ms and 40 ms interpulse intervals, but not at 80 ms or 160 ms intervals. These slices were also characterized by spontaneous and hilar-evoked epileptiform activity in the dentate gyrus in the presence of Mg(2+)-free ACSF containing 100 microM picrotoxin. In contrast, paired-pulse and hilar-evoked responses in slices from injured animals that did not display mossy fiber sprouting were not different from controls. These data suggest the development of spontaneous posttraumatic seizures as well as structural and functional network changes associated with temporal lobe epilepsy in the mouse dentate gyrus by 71 d after CCI injury. Identifying experimental injury models that exhibit similar pathology to injury-induced epilepsy in humans should help to elucidate the mechanisms by which the injured brain becomes epileptic.
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Affiliation(s)
- Robert F Hunt
- Department of Physiology, University of Kentucky, MS-508 Chandler Medical Center, 800 Rose St., Lexington, KY 40536-0298, USA
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20
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Abstract
Postoperative adhesions account for 64-79% of admissions with small bowel obstruction (SBO). The aim of this study was to identify the operative procedures and the types of adhesions that cause SBO. A retrospective analysis of all patients with an admission diagnosis of acute adhesive SBO between January 1982 and December 1990 was performed. One hundred and nineteen patients had 144 admissions with an initial diagnosis of acute SBO due to adhesions. The previous operations were: appendicectomy 23.3%; colorectal resection 20.8%; gynaecological surgery 11.7%; upper gastrointestinal (gastric, biliary or splenic) surgery 9.2%; small bowel surgery 8.3%; and more than one previous abdominal operation 23.6%. Sixty-one admissions required surgery to relieve the SBO. Eighteen patients had strangulated small bowel. All but two of these patients had a single band adhesion causing the SBO and associated strangulation. Band adhesions were commonly found following appendicectomy, colorectal resections or gynaecological operations. Seventeen of the 21 patients with previous surgery for a colorectal malignancy had benign adhesions causing the SBO, while four of the six patients with either previous ovarian or previous gastric carcinoma had recurrent malignancy causing the SBO. Five patients had previously undiagnosed carcinomas (three ovarian and two caecal) as the cause of the SBO.
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Affiliation(s)
- M R Cox
- Department of Surgery, Goulburn Valley Base Hospital, Shepparton, Victoria, Australia
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21
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Abstract
Small bowel obstruction (SBO) due to adhesions is often initially treated non-operatively but the safety and duration of non-operative treatment is controversial. The aims of this study were to assess the safety of non-operative treatment and determine the optimal duration of non-operative treatment in adhesive SBO. A retrospective analysis of patients admitted with a diagnosis of adhesive SBO following an initial period of non-operative treatment was performed. Patients whose condition resolved with non-operative treatment were compared with patients who required surgical intervention after an initial period of non-operative treatment. There were 123 admissions having an initial period of non-operative treatment. The SBO resolved in 85, the remaining 38 required surgical intervention. Complete resolution occurred within 48 h in 75 (88%) cases, the remaining 10 had resolved by 72 h. Thirty-one of 38 patients required surgical intervention for SBO more than 48 h duration after admission. The difference between cases resolving within 48 h and those requiring surgery after 48 h was significant (chi 2 = 113, P < 0.001). Three (2.4%) patients, initially treated non-operatively, had small bowel strangulation. All three were operated on within 24 h of admission when changes in clinical findings suggested small bowel strangulation may be present. There were no deaths in the group having an initial period of non-operative treatment. In the absence of any signs of strangulation, patients with an adhesive SBO can be managed safely with non-operative treatment. Most cases of adhesive SBO that will resolve, do so within 48 h of admission.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M R Cox
- Department of Surgery, Goulburn Valley Base Hospital, Shepparton, Victoria, Australia
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22
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Abstract
Laparoscopic cholecystectomy is rapidly becoming accepted as the best method for the treatment of symptomatic cholelithiasis. Randomized clinical trials comparing laparoscopic cholecystectomy with open cholecystectomy are unlikely to be performed. In order to compare these two operations, surgeons need an historical control group of patients who have undergone a conventional open cholecystectomy. The aim of this study was to document a control group of patients having an open cholecystectomy and compare them with patients having a laparoscopic cholecystectomy. This was achieved by a retrospective study of all patients who had an open cholecystectomy from January 1985 to December 1989. Four hundred and fifty-seven patients, 345 women and 112 men, had a cholecystectomy. Exploration of the common bile duct (ECBD) was performed in 59 (12.5%) cases. The mean operative duration was 73 min for cholecystectomy and 118 min for cholecystectomy and ECBD. The shortest mean postoperative stay was for an elective cholecystectomy (5.3 days) and the longest mean postoperative stay was for urgent admissions requiring ECBD (12.0 days). Operative dissection was difficult in 14.1% of elective cases and 51.8% of urgent cases. Ninety-seven (19.5%) patients had an additional procedure, unrelated to cholelithiasis, at the same operation; 44 did not require laparotomy, 31 had interval appendectomies, and 22 other cases required laparotomy in order to perform the additional procedure. All but one patient required postoperative narcotic analgesia. The mean duration of narcotic analgesia was 2.3 days. The complication rate was 35.2% for cholecystectomy and 62.5% for ECBD. If pulmonary atelectasis is excluded as a complication, these complication rates fell to 6.8% and 20.1%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M R Cox
- Department of Surgery, Goulburn Valley Base Hospital, Shepparton, Victoria, Australia
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23
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Cox MR, James DT, Hunt RF. Infarcation of a jejunal leiomyoma presenting as an acute abdomen. Aust N Z J Surg 1992; 62:76-8. [PMID: 1731743 DOI: 10.1111/j.1445-2197.1992.tb05359.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Leiomyomata of the small intestine are rare benign tumours of the small intestine that usually present with gastrointestinal bleeding, vague abdominal pains or small bowel obstruction. A case is reported of a patient who presented with an acute abdomen due to infarction of a leiomyoma of the proximal jejunum.
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Affiliation(s)
- M R Cox
- Department of Surgery, Goulburn Valley Base Hospital, Shepparton, Victoria
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24
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Abstract
Two patients with focal nodular hyperplasia of the liver and positive results of tests of oestrogen receptor status are described. Both patients were women, both had used oral contraceptive agents and in both the lesion was symptomatic and was surgically resected. The biological and potential therapeutic implications of positive results of tests of oestrogen receptor status in focal nodular hyperplasia is discussed.
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Kune GA, Hunt RF, Jed A, Lusink C, McLaughlin S, Carson P. Wound infection in elective biliary surgery: controlled trial using one dose cephamandole. Aust N Z J Surg 1985; 55:19-22. [PMID: 3901992 DOI: 10.1111/j.1445-2197.1985.tb00848.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In a prospective randomized double-blind trial using a 1 g single dose of cephamandole versus placebo, given 1 h before surgery, the wound infection rate after elective surgery for gallbladder stones in 200 consecutive cases was 11%, being 15% in the placebo group and 7% in the cephamandole group (chi 2 = 4.03; P less than 0.05). The average hospital stay was 7.7 days in the absence of wound infection and 13.6 days in the presence of wound infection. Contaminated bile was significantly positively related to wound infection, and cephamandole significantly protected the culture-positive group from wound infection.
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Kune GA, Hunt RF. Oestrogen receptors in cystadenocarcinoma of the pancreas. Aust N Z J Surg 1984; 54:321-3. [PMID: 6593025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The first case of cystadenocarcinoma of the pancreas in which oestrogen receptors have been detected is reported in a 41 year old woman. The biological and therapeutic implications of this finding are briefly discussed.
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27
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Hunt RF. Preventive dentistry for postoperative hemorrhage. J N C Dent Soc 1968; 51:20-3. [PMID: 5301859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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