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Linghu C, Johnson SL, Valdes PA, Shemesh OA, Park WM, Park D, Piatkevich KD, Wassie AT, Liu Y, An B, Barnes SA, Celiker OT, Yao CC, Yu CCJ, Wang R, Adamala KP, Bear MF, Keating AE, Boyden ES. Spatial Multiplexing of Fluorescent Reporters for Imaging Signaling Network Dynamics. Cell 2020; 183:1682-1698.e24. [PMID: 33232692 DOI: 10.1016/j.cell.2020.10.035] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 10/05/2020] [Accepted: 10/21/2020] [Indexed: 12/23/2022]
Abstract
In order to analyze how a signal transduction network converts cellular inputs into cellular outputs, ideally one would measure the dynamics of many signals within the network simultaneously. We found that, by fusing a fluorescent reporter to a pair of self-assembling peptides, it could be stably clustered within cells at random points, distant enough to be resolved by a microscope but close enough to spatially sample the relevant biology. Because such clusters, which we call signaling reporter islands (SiRIs), can be modularly designed, they permit a set of fluorescent reporters to be efficiently adapted for simultaneous measurement of multiple nodes of a signal transduction network within single cells. We created SiRIs for indicators of second messengers and kinases and used them, in hippocampal neurons in culture and intact brain slices, to discover relationships between the speed of calcium signaling, and the amplitude of PKA signaling, upon receiving a cAMP-driving stimulus.
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Affiliation(s)
- Changyang Linghu
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139, USA
| | - Shannon L Johnson
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Pablo A Valdes
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Or A Shemesh
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Department of Neurobiology and Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Won Min Park
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, KS 66506, USA
| | - Demian Park
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Kiryl D Piatkevich
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China
| | - Asmamaw T Wassie
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA
| | - Yixi Liu
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Bobae An
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA
| | - Stephanie A Barnes
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Picower Institute for Learning and Memory, MIT, Cambridge, MA 02139, USA
| | - Orhan T Celiker
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139, USA
| | - Chun-Chen Yao
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA
| | - Chih-Chieh Jay Yu
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA
| | - Ru Wang
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Katarzyna P Adamala
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mark F Bear
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Picower Institute for Learning and Memory, MIT, Cambridge, MA 02139, USA
| | - Amy E Keating
- Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biology, MIT, Cambridge, MA 02139, USA; Koch Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Edward S Boyden
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Koch Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Cambridge, MA 02139, USA.
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Thomson SR, Seo SS, Barnes SA, Louros SR, Muscas M, Dando O, Kirby C, Wyllie DJA, Hardingham GE, Kind PC, Osterweil EK. Cell-Type-Specific Translation Profiling Reveals a Novel Strategy for Treating Fragile X Syndrome. Neuron 2017; 95:550-563.e5. [PMID: 28772121 PMCID: PMC5548955 DOI: 10.1016/j.neuron.2017.07.013] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [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: 12/06/2016] [Revised: 04/22/2017] [Accepted: 07/12/2017] [Indexed: 11/08/2022]
Abstract
Excessive mRNA translation downstream of group I metabotropic glutamate receptors (mGlu1/5) is a core pathophysiology of fragile X syndrome (FX); however, the differentially translating mRNAs that contribute to altered neural function are not known. We used translating ribosome affinity purification (TRAP) and RNA-seq to identify mistranslating mRNAs in CA1 pyramidal neurons of the FX mouse model (Fmr1−/y) hippocampus, which exhibit exaggerated mGlu1/5-induced long-term synaptic depression (LTD). In these neurons, we find that the Chrm4 transcript encoding muscarinic acetylcholine receptor 4 (M4) is excessively translated, and synthesis of M4 downstream of mGlu5 activation is mimicked and occluded. Surprisingly, enhancement rather than inhibition of M4 activity normalizes core phenotypes in the Fmr1−/y, including excessive protein synthesis, exaggerated mGluR-LTD, and audiogenic seizures. These results suggest that not all excessively translated mRNAs in the Fmr1−/y brain are detrimental, and some may be candidates for enhancement to correct pathological changes in the FX brain. TRAP-seq reveals altered translation of >120 mRNAs in Fmr1−/y CA1 pyramidal neurons Muscarinic receptor M4 is excessively translated in Fmr1−/y hippocampus Enhancement, not inhibition, of M4 corrects core phenotypes in the Fmr1−/y mouse Not all excessively translating mRNAs are detrimental to Fmr1−/y brain function
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Affiliation(s)
- Sophie R Thomson
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Sang S Seo
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Stephanie A Barnes
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Susana R Louros
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Melania Muscas
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Owen Dando
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Caoimhe Kirby
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - David J A Wyllie
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Giles E Hardingham
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; UK Dementia Research Institute, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Peter C Kind
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Emily K Osterweil
- Centre for Integrative Physiology/Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
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Grayson B, Barnes SA, Markou A, Piercy C, Podda G, Neill JC. Postnatal Phencyclidine (PCP) as a Neurodevelopmental Animal Model of Schizophrenia Pathophysiology and Symptomatology: A Review. Curr Top Behav Neurosci 2016; 29:403-428. [PMID: 26510740 DOI: 10.1007/7854_2015_403] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cognitive dysfunction and negative symptoms of schizophrenia remain an unmet clinical need. Therefore, it is essential that new treatments and approaches are developed to recover the cognitive and social impairments that are seen in patients with schizophrenia. These may only be discovered through the use of carefully validated, aetiologically relevant and translational animal models. With recent renewed interest in the neurodevelopmental hypothesis of schizophrenia, postnatal administration of N-methyl-D-aspartate receptor (NMDAR) antagonists such as phencyclidine (PCP) has been proposed as a model that can mimic aspects of schizophrenia pathophysiology. The purpose of the current review is to examine the validity of this model and compare it with the adult subchronic PCP model. We review the ability of postnatal PCP administration to produce behaviours (specifically cognitive deficits) and neuropathology of relevance to schizophrenia and their subsequent reversal by pharmacological treatments. We review studies investigating effects of postnatal PCP on cognitive domains in schizophrenia in rats. Morris water maze and delayed spontaneous alternation tasks have been used for working memory, attentional set-shifting for executive function, social novelty discrimination for selective attention and prepulse inhibition of acoustic startle for sensorimotor gating. In addition, we review studies on locomotor activity and neuropathology. We also include two studies using dual hit models incorporating postnatal PCP and two studies on social behaviour deficits following postnatal PCP. Overall, the evidence we provide supports the use of postnatal PCP to model cognitive and neuropathological disturbances of relevance to schizophrenia. To date, there is a lack of evidence to support a significant advantage of postnatal PCP over the adult subchronic PCP model and full advantage has not been taken of its neurodevelopmental component. When thoroughly characterised, it is likely that it will provide a useful neurodevelopmental model to complement other models such as maternal immune activation, particularly when combined with other manipulations to produce dual or triple hit models. However, the developmental trajectory of behavioural and neuropathological changes induced by postnatal PCP and their relevance to schizophrenia must be carefully mapped out. Overall, we support further development of dual (or triple) hit models incorporating genetic, neurodevelopmental and appropriate environmental elements in the search for more aetiologically valid animal models of schizophrenia and neurodevelopmental disorders (NDDs).
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Affiliation(s)
- B Grayson
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
| | - S A Barnes
- Department of Psychiatry, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0603, USA
| | - A Markou
- Department of Psychiatry, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0603, USA
| | - C Piercy
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - G Podda
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - J C Neill
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
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Barnes SA, Young JW, Bate ST, Neill JC. Dopamine D1 receptor activation improves PCP-induced performance disruption in the 5C-CPT by reducing inappropriate responding. Behav Brain Res 2015; 300:45-55. [PMID: 26658514 DOI: 10.1016/j.bbr.2015.11.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [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: 06/16/2015] [Revised: 11/25/2015] [Accepted: 11/26/2015] [Indexed: 11/19/2022]
Abstract
Attentional deficits contribute significantly to the functional disability of schizophrenia patients. The 5-choice continuous performance test (5C-CPT) measures attention in mice, rats, and humans, requiring the discrimination of trial types that either require a response or the inhibition of a response. The 5C-CPT, one version of human continuous performance tests (CPT), enables attentional testing in rodents in a manner consistent with humans. Augmenting the prefrontal cortical dopaminergic system has been proposed as a therapeutic target to attenuate the cognitive disturbances associated with schizophrenia. Using translational behavioural tasks in conjunction with inducing conditions relevant to schizophrenia pathophysiology enable the assessment of pro-attentive properties of compounds that augment dopaminergic activity. Here, using a repeated phencyclidine (PCP) treatment regimen and the 5C-CPT paradigm, we assess the pro-attentive properties of SKF 38393, a dopamine D1 receptor agonist, in rats. We show that repeated PCP treatment induces robust deficits in 5C-CPT performance indicative of impaired attention. Pre-treatment with SKF 38393 partially attenuates the PCP-induced deficits in 5C-CPT performance by reducing false alarm responding and increasing response accuracy. Impaired target detection was still evident in SKF 38393-treated rats however. Thus, augmentation of the dopamine D1 system improves PCP-induces deficits in 5C-CPT performance by selectively reducing aspects of inappropriate responding. These findings provide evidence to support the hypothesis that novel therapies targeting the dopamine D1 receptor system could improve aspects of attentional deficits in schizophrenia patients.
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Affiliation(s)
- S A Barnes
- Department of Psychiatry, University of California San Diego, CA, USA.
| | - J W Young
- Department of Psychiatry, University of California San Diego, CA, USA; Research Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - S T Bate
- Statistical Sciences Europe, GlaxoSmithKline Pharmaceuticals, Stevenage SG1 2NY, UK
| | - J C Neill
- Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
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Barnes SA, Pinto-Duarte A, Kappe A, Zembrzycki A, Metzler A, Mukamel EA, Lucero J, Wang X, Sejnowski TJ, Markou A, Behrens MM. Disruption of mGluR5 in parvalbumin-positive interneurons induces core features of neurodevelopmental disorders. Mol Psychiatry 2015; 20:1161-72. [PMID: 26260494 PMCID: PMC4583365 DOI: 10.1038/mp.2015.113] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Revised: 06/21/2015] [Accepted: 07/06/2015] [Indexed: 12/13/2022]
Abstract
Alterations in glutamatergic transmission onto developing GABAergic systems, in particular onto parvalbumin-positive (Pv(+)) fast-spiking interneurons, have been proposed as underlying causes of several neurodevelopmental disorders, including schizophrenia and autism. Excitatory glutamatergic transmission, through ionotropic and metabotropic glutamate receptors, is necessary for the correct postnatal development of the Pv(+) GABAergic network. We generated mutant mice in which the metabotropic glutamate receptor 5 (mGluR5) was specifically ablated from Pv(+) interneurons postnatally, and investigated the consequences of such a manipulation at the cellular, network and systems levels. Deletion of mGluR5 from Pv(+) interneurons resulted in reduced numbers of Pv(+) neurons and decreased inhibitory currents, as well as alterations in event-related potentials and brain oscillatory activity. These cellular and sensory changes translated into domain-specific memory deficits and increased compulsive-like behaviors, abnormal sensorimotor gating and altered responsiveness to stimulant agents. Our findings suggest a fundamental role for mGluR5 in the development of Pv(+) neurons and show that alterations in this system can produce broad-spectrum alterations in brain network activity and behavior that are relevant to neurodevelopmental disorders.
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Affiliation(s)
- SA Barnes
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - A Pinto-Duarte
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - A Kappe
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - A Zembrzycki
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - A Metzler
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - EA Mukamel
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - J Lucero
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - X Wang
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - TJ Sejnowski
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA,Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA, USA,Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - A Markou
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - MM Behrens
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
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Till SM, Asiminas A, Jackson AD, Katsanevaki D, Barnes SA, Osterweil EK, Bear MF, Chattarji S, Wood ER, Wyllie DJA, Kind PC. Conserved hippocampal cellular pathophysiology but distinct behavioural deficits in a new rat model of FXS. Hum Mol Genet 2015; 24:5977-84. [PMID: 26243794 PMCID: PMC4599667 DOI: 10.1093/hmg/ddv299] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [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: 06/17/2015] [Accepted: 07/21/2015] [Indexed: 11/17/2022] Open
Abstract
Recent advances in techniques for manipulating genomes have allowed the generation of transgenic animals other than mice. These new models enable cross-mammalian comparison of neurological disease from core cellular pathophysiology to circuit and behavioural endophenotypes. Moreover they will enable us to directly test whether common cellular dysfunction or behavioural outcomes of a genetic mutation are more conserved across species. Using a new rat model of Fragile X Syndrome, we report that Fmr1 knockout (KO) rats exhibit elevated basal protein synthesis and an increase in mGluR-dependent long-term depression in CA1 of the hippocampus that is independent of new protein synthesis. These defects in plasticity are accompanied by an increase in dendritic spine density selectively in apical dendrites and subtle changes in dendritic spine morphology of CA1 pyramidal neurons. Behaviourally, Fmr1 KO rats show deficits in hippocampal-dependent, but not hippocampal-independent, forms of associative recognition memory indicating that the loss of fragile X mental retardation protein (FMRP) causes defects in episodic-like memory. In contrast to previous reports from mice, Fmr1 KO rats show no deficits in spatial reference memory reversal learning. One-trial spatial learning in a delayed matching to place water maze task was also not affected by the loss of FMRP in rats. This is the first evidence for conservation across mammalian species of cellular and physiological hippocampal phenotypes associated with the loss of FMRP. Furthermore, while key cellular phenotypes are conserved they manifest in distinct behavioural dysfunction. Finally, our data reveal novel information about the selective role of FMRP in hippocampus-dependent associative memory.
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Affiliation(s)
- Sally M Till
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Antonis Asiminas
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Cognitive and Neural Systems, The University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Adam D Jackson
- Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Brain Development and Repair, The Institute for Stem Cell Biology and Regenerative Medicine, Bangalore 560065, India
| | - Danai Katsanevaki
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Stephanie A Barnes
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Emily K Osterweil
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK, Department of Brain and Cognitive Sciences, Howard Hughes Medical Institute, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge MA 02139, USA and
| | - Mark F Bear
- Department of Brain and Cognitive Sciences, Howard Hughes Medical Institute, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge MA 02139, USA and
| | - Sumantra Chattarji
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Brain Development and Repair, The Institute for Stem Cell Biology and Regenerative Medicine, Bangalore 560065, India, National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, India
| | - Emma R Wood
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Cognitive and Neural Systems, The University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - David J A Wyllie
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Brain Development and Repair, The Institute for Stem Cell Biology and Regenerative Medicine, Bangalore 560065, India
| | - Peter C Kind
- Patrick Wild Centre, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Integrative Physiology, The University of Edinburgh, Edinburgh EH8 9XD, UK, Centre for Brain Development and Repair, The Institute for Stem Cell Biology and Regenerative Medicine, Bangalore 560065, India,
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Abstract
Light signal-transduction pathways are a central component of the mechanisms that regulate plant development. These pathways provide the means by which information from specific wavelengths of light may be amplified and coordinated, resulting in complex physiological and developmental responses. This review focuses upon recent approaches towards establishing the intermediates that transmit signals from photoreceptors, phytochromes in particular, to target elements in the promoters of light-regulated genes.
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Affiliation(s)
- S A Barnes
- The Laboratory of Plant Molecular Biology, The Rockefeller University, New York, NY 10021-6399, USA; The Institute of Molecular Agrobiology, Singapore 118240
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Hassan I, You YN, Cima RR, Larson DW, Dozois EJ, Barnes SA, Pemberton JH. Hand-assisted versus laparoscopic-assisted colorectal surgery: Practice patterns and clinical outcomes in a minimally-invasive colorectal practice. Surg Endosc 2008; 22:739-43. [PMID: 17704883 DOI: 10.1007/s00464-007-9477-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [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: 11/26/2022]
Abstract
INTRODUCTION Laparoscopic assisted (LA) colectomy has significant patient benefits but is technically challenging. Hand-assisted laparoscopic surgery (HALS) allows tactile feedback because the surgeon's hand assists in retraction and dissection. This may decrease the technical difficulty and shorten the learning curve associated with performing laparoscopic colectomy. We investigated the patient selection and short-term clinical outcomes of HALS and LA since the introduction of HALS to our minimally invasive colorectal practice. METHODS Prospectively collected data on 258 patients undergoing HALS (n = 109) or LA colectomy (n = 149) during a calendar year (2004) were analyzed. Patient and disease characteristics, operative parameters, and perioperative outcomes were compared. RESULTS HALS patients were similar to LA patients in age (51 vs. 54 yrs), gender (56 vs. 52% male), body mass index (26 vs. 26 kg/m2), comorbidities (84 vs. 85% with one or more), and diagnosis (83 vs. 80% benign), but differed in incidence of previous surgery (49 vs. 30%; P = 0.008). A significantly greater proportion of HALS patients underwent complex procedures and extensive resections. Conversion rates (15 vs. 11%, P = 0.44), intraoperative complications (4 vs. 1%, P = 0.17), 30-day morbidity (18 vs. 11%, P = 0.12) and surgical reinterventions (2 vs. 1%, P = 0.58) did not differ. Recovery measured by days to flatus was not different [mean (standard deviation) 3(2) vs. 3(2) days, P = 0.26], however HALS patients had longer operative times [276(96) vs. 211(107) minutes P < 0.0001] and 1 day longer stay in hospital [6(3) vs. 5 (3) days, P = 0.0009)]. CONCLUSIONS Patients undergoing HALS underwent more-complex procedures than LA patients but retained the short-term benefits associated with LA colectomy. HALS facilitates expansion of a minimally invasive colectomy practice to include more challenging procedures while maintaining short-term patient benefits.
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Affiliation(s)
- Imran Hassan
- Division of General Surgery, SIU School of Medicine, Springfield, II 62794, USA
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Charkoudian N, Joyner MJ, Barnes SA, Johnson CP, Eisenach JH, Dietz NM, Wallin BG. Relationship between muscle sympathetic nerve activity and systemic hemodynamics during nitric oxide synthase inhibition in humans. Am J Physiol Heart Circ Physiol 2006; 291:H1378-83. [PMID: 16648188 DOI: 10.1152/ajpheart.00234.2006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Large interindividual differences exist in resting sympathetic nerve activity (SNA) among normotensive humans with similar arterial pressure (AP). We recently showed inverse relationships of resting SNA with cardiac output (CO) and vascular adrenergic responsiveness that appear to balance the influence of differences in SNA on blood pressure. In the present study, we tested whether nitric oxide (NO)-mediated vasodilation has a role in this balance by evaluating hemodynamic responses to systemic NO synthase (NOS) inhibition in individuals with low and high resting muscle SNA (MSNA). We measured MSNA via peroneal microneurography, CO via acetylene uptake and AP directly, at baseline and during increasing systemic doses of the NOS inhibitor NG-monomethyl-l-arginine (l-NMMA). Baseline MSNA ranged from 9 to 38 bursts/min (13 to 68 bursts/100 heartbeats). l-NMMA caused dose-dependent increases in AP and total peripheral resistance and reflex decreases in CO and MSNA. Increases in AP with l-NMMA were greater in individuals with high baseline MSNA ( PANOVA < 0.05). For example, after 8.5 mg/kg of l-NMMA, in the low MSNA subgroup ( n = 6, 28 ± 4 bursts/100 heartbeats), AP increased 9 ± 1 mmHg, whereas in the high-MSNA subgroup ( n = 6, 58 ± 3 bursts/100 heartbeats), AP increased 15 ± 2 mmHg ( P < 0.01). The high-MSNA subgroup had lower baseline CO and smaller decreases in CO with l-NMMA, but changes in total peripheral resistance were not different between groups. We conclude that differences in CO among individuals with varying sympathetic traffic have important hemodynamic implications during disruption of NO-mediated vasodilation.
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Affiliation(s)
- N Charkoudian
- Department of Physiology and Biomedical Engineering, JO 4-184W, Mayo Clinic College of Medicine, 200 First St. SW, Rochester, MN 55905, USA.
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10
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Affiliation(s)
- J A Napier
- Department of Agricultural Sciences, University of Bristol, UK
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11
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Page CW, Barnes SA, Fisher WE. Ulcer necessitans: a forgotten entity. Surgery 2000; 127:593-4. [PMID: 10819071 DOI: 10.1067/msy.2000.104405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- C W Page
- Department of Surgery, Baylor College of Medicine, Houston, Tex., USA
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Affiliation(s)
- Ryan B. Prince
- Contribution from the School of Chemical Sciences and the Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois 61801
| | - Stephanie A. Barnes
- Contribution from the School of Chemical Sciences and the Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois 61801
| | - Jeffrey S. Moore
- Contribution from the School of Chemical Sciences and the Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois 61801
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13
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Knight JS, Madueño F, Barnes SA, Gray JC. Manipulating photosynthesis. Mol Biotechnol 1996; 6:335-45. [PMID: 9067979 DOI: 10.1007/bf02761712] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The levels of individual photosynthetic proteins can be independently decreased by the Agrobacterium-mediated transformation of plants with antisense RNA constructs. Protocols for the introduction of such constructs into Agrobacterium, the Agrobacterium-mediated transformation of tobacco leaf disks, and the screening and analysis of the transgenic plants produced are described.
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Affiliation(s)
- J S Knight
- School of Biological Sciences, University of Manchester, UK.
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14
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Abstract
Physiological analysis of the fhy1 mutant of Arabidopsis has led to the proposal that the mutant is deficient in a downstream component of the phytochrome A signal transduction pathway. To define this lesion at the molecular level, we have examined the expression of a range of phytochrome-regulated genes in fhy1. In far-red light, the regulation of genes such as CHS and CHI is blocked in fhy1, whereas the induction of CAB and NR genes is affected minimally. In contrast, the induction of all genes tested is blocked in a phytochrome A-deficient mutant, confirming that gene expression in far-red light is regulated solely by phytochrome A. Thus, fhy1 defines a branch point in phytochrome A signal transduction pathways for gene expression. Contrary to the general opinion that responses to continuous red light are mediated by phytochrome B and other photostable phytochromes, we have shown also that red light-induction of CHS is mediated almost entirely by phytochrome A. Furthermore, phytochrome A-mediated induction of CHS by red light is blocked in fhy1. The induction of CHS by blue light, however, is normal in fhy1, suggesting that although FHY1 is a component of the phytochrome A signaling pathway, it is not a component of the blue-light signaling pathway for CHS expression.
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Affiliation(s)
- S A Barnes
- Laboratory of Plant Molecular Biology, Rockefeller University, New York, NY 10021-6399, USA
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15
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Barnes SA, Nishizawa NK, Quaggio RB, Whitelam GC, Chua NH. Far-red light blocks greening of Arabidopsis seedlings via a phytochrome A-mediated change in plastid development. Plant Cell 1996; 8:601-15. [PMID: 8624438 PMCID: PMC161123 DOI: 10.1105/tpc.8.4.601] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We have characterized a far-red-light response that induces a novel pathway for plastid development in Arabidopsis seedlings. This response results in the inability of cotyledons to green upon subsequent white light illumination, and the response is suppressed by exogenous sucrose. Studies with mutants showed that this far-red block of greening is phytochrome A dependent and requires an intact downstream signaling pathway in which FHY1 and FHY3 may be components but in which HY5 is not. This highlights a previously undefined branchpoint in the phytochrome signaling pathway. Ultrastructural analysis showed that the far-red block correlates with both the failure of plastids to accumulate prolamellar bodies and the formation of vesicles in the stroma. We present evidence that the far-red block of greening is the result of severe repression of protochlorophyllide reductase (POR) genes by far-red light coupled with irreversible plastid damage. This results in the temporal separation of phytochrome-mediated POR; repression from light-dependent protochlorophyllide reduction, two processes that normally occur in coordination in white light.
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Affiliation(s)
- S A Barnes
- Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-6399,USA
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16
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Barnes SA, Quaggio RB, Chua NH. Phytochrome signal-transduction: characterization of pathways and isolation of mutants. Philos Trans R Soc Lond B Biol Sci 1995; 350:67-74. [PMID: 8577852 DOI: 10.1098/rstb.1995.0139] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [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: 01/31/2023] Open
Abstract
The study of phytochrome signalling has yielded a wealth of data describing both the perception of light by the receptor, and the terminal steps in phytochrome-regulated gene expression by a number of transcription factors. We are now focusing on establishing the intervening steps linking phytochrome photoactivation to gene expression, and the regulation and interactions of these signalling pathways. Recent work has utilized both a pharmacological approach in phototrophic soybean suspension cultures and microinjection techniques in tomato to establish three distinct phytochrome signal-transduction pathways: (i) a calcium-dependent pathway that regulates the expression of genes encoding the chlorophyll a/b binding protein (CAB) and other components of photosystem II; (ii) a cGMP-dependent pathway that regulates the expression of the gene encoding chalcone synthase (CHS) and the production of anthocyanin pigments; and (iii) a pathway dependent upon both calcium and cGMP that regulates the expression of genes encoding components of photosystem I and is necessary for the production of mature chloroplasts. To study the components and the regulation of phytochrome signal-transduction pathways, mutants with altered photomorphogenic responses have been isolated by a number of laboratories. However, with several possible exceptions, little real progress has been made towards the isolation of mutants in positive regulatory elements of the phytochrome signal-transduction pathway. We have characterized a novel phytochrome A (PhyA)-mediated far-red light (FR) response in Arabidopsis seedlings which we are currently using to screen for specific phyA signal-transduction mutants.
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Affiliation(s)
- S A Barnes
- Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-6399, USA
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Abstract
The decision to perform surgical versus nonoperative palliation for unresectable pancreatic cancer is influenced by a number of factors. In most cases, patient symptoms clearly dictate the management. In patients with symptoms of duodenal obstruction at the time of presentation, surgery is the only option. In patients with obstructive jaundice alone, the options for management must be weighed against factors such as overall health status, projected survival, and procedure-related morbidity and mortality. A prospective multicenter trial recently analyzed factors influencing perioperative morbidity and mortality following both curative and palliative surgery for pancreatic cancer. This analysis demonstrated that preoperative diabetes, low Kanofsky's index, and liver metastases are significant risk factors in predicting perioperative morbidity and mortality in patients undergoing palliative procedures for pancreatic cancer. Another analysis focusing on tumor characteristics suggested that for patients with Stage I and Stage II disease (i.e., with no evidence of systemic metastases), survival and the potential for late duodenal obstruction favor surgical management. In summary, although patient management must be individualized, most patients with pancreatic cancer in good medical health and with no evidence of systemic disease are most appropriately managed with surgical palliation. This option affords patients the best chance of avoiding the late complications of recurrent jaundice, duodenal obstruction, and disabling pain. Surgical palliation can generally be completed with an acceptable perioperative morbidity and mortality and a hospital stay of approximately 2 weeks. Finally, only surgical exploration can offer full opportunity for resection for cure.
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Affiliation(s)
- K D Lillemoe
- Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
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Knight JS, Madueño F, Barnes SA, Gray JC. Manipulating photosynthesis in transgenic plants. Methods Mol Biol 1995; 44:263-80. [PMID: 7581671 DOI: 10.1385/0-89603-302-3:263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- J S Knight
- Department of Plant Sciences, University of Cambridge, UK
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Huebner RE, Schein MF, Hall CA, Barnes SA. Delayed-type hypersensitivity anergy in human immunodeficiency virus-infected persons screened for infection with Mycobacterium tuberculosis. Clin Infect Dis 1994; 19:26-32. [PMID: 7948554 DOI: 10.1093/clinids/19.1.26] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [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: 01/28/2023] Open
Abstract
A total of 479 human immunodeficiency virus (HIV)-infected persons at an HIV clinic in Florida and a tuberculosis clinic in New Jersey were skin-tested with tuberculin, tetanus toxoid, mumps antigen, and Candida antigen in a study of the prevalence of delayed-type hypersensitivity (DTH) anergy and the usefulness of two-step tuberculin testing in this population. Of the patients tested, 12% had a positive (> or = 5-mm) response to tuberculin; 57%, 45%, and 35% had a positive (> or = 3-mm) response to Candida antigen, tetanus toxoid, and mumps antigen, respectively; and 31% were anergic (< 3 mm of induration in response to each antigen). In a multivariate logistic regression model, anergy was significantly associated with a history of Kaposi's sarcoma, Pneumocystis carinii pneumonia, or oral candidiasis and with White race. Anergy was four times and 15 times as likely for persons with CD4+ T-lymphocyte counts of 200-400/mm3 and < 200/mm3, respectively, as for persons with > 499 CD4+ T lymphocytes/mm3. Of 103 patients who were tuberculin-tested a second time after their initial test result was negative, seven had > or = 5 mm of induration in response to the second test; only one of these patients was anergic at the initial screening. The findings of this study indicate that DTH antigens should be used in conjunction with tuberculin testing and that two-step tuberculin testing is not an alternative to anergy testing but may be useful for the detection of infection with Mycobacterium tuberculosis in nonanergic HIV-infected patients.
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Affiliation(s)
- R E Huebner
- Clinical Research Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30333
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Abstract
A retrospective cross-sectional cephalometric investigation was undertaken to examine the facial form of a group of Finnish children with juvenile chronic arthritis (JCA). Following digitization, the radiographs were divided into three age groups, and according to whether or not 'bird-face' deformity was present. From a total of 67 cases (39 females and 28 males) 19 per cent were judged to be 'affected'. Analyses were carried out and the groups compared using t-tests. The mandible was found to be smaller both in ramal height and body length in the affected sample, with reduction in posterior face height being only partly compensated by increase in bony apposition at the angle producing antegonial notching. There was posterior rotation of the mandible with a reduction in angles S-N-B and S-N-Pog, and an increase in the gonial angle, the angle between the mandibular plane and S-N, maxillary, and occlusal planes. The changes in the maxilla were less marked. Although S-N-A was reduced in all three age groups, it was not significantly so. Maxillary length (ANS-PNS) was significantly smaller in the two younger age groups. In the vertical plane maxillary dimensions were reduced in the two younger age groups. A highly significant increase in the occlusal to maxillary planes angle was observed in all groups. There was, however, no difference in S-N to maxillary planes angle, indicating a more steeply inclined occlusal plane due to subnormally erupted maxillary molars. Although the inter-incisal angle was reduced there was no significant difference in the incisor inclinations in relation to the jaws and despite the posterior rotation of the mandible there was no significant increase in size of overjet or in the frequency of anterior open bite.
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Affiliation(s)
- O Rönning
- Institute of Dentistry, University of Turku, Finland
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Stang JM, Washington SE, Barnes SA, Dutko HJ, Cheney BD, Easter CR, O'Hara JT, Kessler JH, Schaal SF, Lewis RP. Treatment of prehospital refractory ventricular fibrillation with bretylium tosylate. Ann Emerg Med 1984; 13:234-6. [PMID: 6703428 DOI: 10.1016/s0196-0644(84)80469-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Among 218 patients treated for prehospital arrest during an eight-month baseline period prior to addition of bretylium tosylate to the paramedic protocol in Columbus, 16 (7.3%) were seen with refractory ventricular fibrillation (RVF). These patients failed to respond to multiple countershocks, lidocaine, bicarbonate and epinephrine, and either were transported in arrest during cardiopulmonary resuscitation (CPR)(14) or were pronounced dead at the scene (2). A single patient was eventually resuscitated in and discharged from the hospital. During the subsequent 16 1/2-month experience with bretylium used only for prehospital RVF, 421 patients with prehospital arrest were seen, 35 of whom (8.3%) had RVF. All but five patients were defibrillated successfully, and 14 (40%) were converted to a rhythm sufficient to obviate CPR during transportation. Eleven patients (31%) survived to be admitted to the hospital, and eight of 35 (23% vs 1/16 or 6.2% above, P less than .05) were discharged and remained well three to 17 months later. Bretylium tosylate may provide life-saving therapy for refractory prehospital ventricular fibrillation so that survival from an almost uniformly fatal condition is improved. While patients with persistent arrest generally should be transported to the hospital, such patients should not be subjected to the difficulties of CPR in transit unless they are first given bretylium if RVF is present.
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