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Kulkarni S, Saha M, Slosberg J, Singh A, Nagaraj S, Becker L, Zhang C, Bukowski A, Wang Z, Liu G, Leser JM, Kumar M, Bakhshi S, Anderson MJ, Lewandoski M, Vincent E, Goff LA, Pasricha PJ. Age-associated changes in lineage composition of the enteric nervous system regulate gut health and disease. eLife 2023; 12:RP88051. [PMID: 38108810 PMCID: PMC10727506 DOI: 10.7554/elife.88051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023] Open
Abstract
The enteric nervous system (ENS), a collection of neural cells contained in the wall of the gut, is of fundamental importance to gastrointestinal and systemic health. According to the prevailing paradigm, the ENS arises from progenitor cells migrating from the neural crest and remains largely unchanged thereafter. Here, we show that the lineage composition of maturing ENS changes with time, with a decline in the canonical lineage of neural-crest derived neurons and their replacement by a newly identified lineage of mesoderm-derived neurons. Single cell transcriptomics and immunochemical approaches establish a distinct expression profile of mesoderm-derived neurons. The dynamic balance between the proportions of neurons from these two different lineages in the post-natal gut is dependent on the availability of their respective trophic signals, GDNF-RET and HGF-MET. With increasing age, the mesoderm-derived neurons become the dominant form of neurons in the ENS, a change associated with significant functional effects on intestinal motility which can be reversed by GDNF supplementation. Transcriptomic analyses of human gut tissues show reduced GDNF-RET signaling in patients with intestinal dysmotility which is associated with reduction in neural crest-derived neuronal markers and concomitant increase in transcriptional patterns specific to mesoderm-derived neurons. Normal intestinal function in the adult gastrointestinal tract therefore appears to require an optimal balance between these two distinct lineages within the ENS.
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Affiliation(s)
- Subhash Kulkarni
- Division of Gastroenterology, Dept of Medicine, Beth Israel Deaconess Medical CenterBostonUnited States
- Division of Medical Sciences, Harvard Medical SchoolBostonUnited States
| | - Monalee Saha
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Jared Slosberg
- Department of Genetic Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Alpana Singh
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Sushma Nagaraj
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Laren Becker
- Division of Gastroenterology, Stanford University – School of MedicineStanfordUnited States
| | - Chengxiu Zhang
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Alicia Bukowski
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Zhuolun Wang
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Guosheng Liu
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Jenna M Leser
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Mithra Kumar
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Shriya Bakhshi
- Center for Neurogastroenterology, Department of Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Matthew J Anderson
- Center for Cancer Research, National Cancer InstituteFrederickUnited States
| | - Mark Lewandoski
- Center for Cancer Research, National Cancer InstituteFrederickUnited States
| | - Elizabeth Vincent
- Department of Genetic Medicine, Johns Hopkins University – School of MedicineBaltimoreUnited States
| | - Loyal A Goff
- Department of Neuroscience, Johns Hopkins University – School of MedicineBaltimoreUnited States
- Kavli Neurodiscovery Institute, Johns Hopkins University – School of MedicineBaltimoreUnited States
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Mayerl CJ, Gould FDH, Adjerid K, Edmonds C, German RZ. The Pathway from Anatomy and Physiology to Diagnosis: A Developmental Perspective on Swallowing and Dysphagia. Dysphagia 2023; 38:33-41. [PMID: 35441265 PMCID: PMC9579268 DOI: 10.1007/s00455-022-10449-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 04/04/2022] [Indexed: 01/29/2023]
Abstract
Dysphagia results from diverse and distinct etiologies. The pathway from anatomy and physiology to clinical diagnosis is complex and hierarchical. Our approach in this paper is to show the linkages from the underlying anatomy and physiology to the clinical presentation. In particular, the terms performance, function, behavior, and physiology are often used interchangeably, which we argue is an obstacle to clear discussion of mechanism of pathophysiology. We use examples from pediatric populations to highlight the importance of understanding anatomy and physiology to inform clinical practice. We first discuss the importance of understanding anatomy in the context of physiology and performance. We then use preterm infants and swallow-breathe coordination as examples to explicate the hierarchical nature of physiology and its impact on performance. We also highlight where the holes in our knowledge lie, with the ultimate endpoint of providing a framework that could enhance our ability to design interventions to help patients. Clarifying these terms, and the roles they play in the biology of dysphagia will help both the researchers studying the problems as well as the clinicians applying the results of those studies.
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Affiliation(s)
- C J Mayerl
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, 44272, USA
| | - F D H Gould
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA
| | - K Adjerid
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, 44272, USA
| | - C Edmonds
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, 44272, USA
| | - R Z German
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, 44272, USA.
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Non-invasive brain stimulation for treating neurogenic dysarthria: A systematic review. Ann Phys Rehabil Med 2021; 65:101580. [PMID: 34626861 DOI: 10.1016/j.rehab.2021.101580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 07/08/2021] [Accepted: 07/19/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Although non-invasive central and peripheral stimulations are accruing support as promising treatments in different neurological conditions, their effects on dysarthria have not been systematically investigated. OBJECTIVE The purpose of this review was to examine the evidence base of non-invasive stimulation for treating dysarthria, identify which stimulation parameters have the most potential for treatment and determine safety risks. METHODS A systematic review with meta-analysis, when possible, involving publications indexed in MEDLINE, PsychINFO, EMBASE CINHAL the Linguistics and Language Behavioral Abstracts, Web of Science, Cochrane Register of Control Trials and 2 trial registries was completed. Articles were searched in December 2018 and updated in June 2021 using keywords related to brain and electrical stimulation, dysarthria and research design. We included trials with randomised, cross-over or quasi-experimental designs; involving a control group; and investigating treatment of neurogenic dysarthria with non-invasive stimulation. Methodological quality was determined with the Cochrane's Risk of Bias-2 tool. RESULTS In total, 6186 studies were identified; 10 studies (6 randomised controlled trials and 4 cross-over studies) fulfilled the inclusion criteria. All 10 trials (268 adults with Parkinson's disease, stroke and neurodegenerative cerebellar ataxia) focused on brain stimulation (6 repetitive transcranial magnetic stimulation; 3 transcranial direct current stimulation; and 1 repetitive transorbital alternating current stimulation). Adjunct speech-language therapy was delivered in 2 trials. Most trials reported one or more positive effects of stimulation on dysarthria-related features; however, given the overall high risk of bias and heterogeneity in participant, trial and outcome measurement characteristics, no conclusions can be drawn. Post-treatment size effects for 2 stroke trials demonstrated no statistically significant differences between active and sham stimulation across 3 dysarthria outcomes. CONCLUSIONS Evidence for use of non-invasive brain stimulation in treating dysarthria remains inconclusive. Research trials that provide reliable and replicable findings are required.
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Le Perf G, Donguy AL, Thebault G. Nuanced effects of music interventions on rehabilitation outcomes after stroke: a systematic review. Top Stroke Rehabil 2019; 26:473-484. [DOI: 10.1080/10749357.2019.1623518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Gaël Le Perf
- Physical Medicine and Rehabilitation Department, Centre Hospitalier Paul Coste Floret, Lamalou-les-Bains, France
| | - Anne-Lise Donguy
- Physical Medicine and Rehabilitation Department, SSR La Petite Paix, Lamalou-les-Bains, France
| | - Guillaume Thebault
- Physical Medicine and Rehabilitation Department, Centre Hospitalier Paul Coste Floret, Lamalou-les-Bains, France
- Dynamique des Capacités Humaines et des Conduites de Santé (Epsylon), Université Montpellier, Montpellier, France
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Potter NL, Nievergelt Y, VanDam M. Tongue Strength in Children With and Without Speech Sound Disorders. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2019; 28:612-622. [PMID: 31136240 PMCID: PMC6802864 DOI: 10.1044/2018_ajslp-18-0023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/01/2018] [Accepted: 10/23/2018] [Indexed: 06/01/2023]
Abstract
Purpose The purpose of this cross-sectional investigation was to expand the comparative database of pediatric tongue strength for children and adolescents with typical development, ages 3-17 years, and compare tongue strength among children with typical development, speech sound delay/disorders (SD), and motor speech disorders (MSDs). Method Tongue strength was measured using the Iowa Oral Performance Instrument in a total of 286 children and adolescents, 228 with typical development, 16 with SD, and 42 with MSDs, including classic galactosemia, a known risk factor for MSD ( n = 33) and idiopathic MSD ( n = 9). Results For all groups, tongue strength increased rapidly from 3 to 6.5 years of age and then continued to increase with age at a slower rate until 17 years of age. Children with SD's tongue strength did not differ from their typically developing (TD) peers. Children and adolescents with MSDs had decreased tongue strength compared to children with typical development or SD. Tongue strength was not related to severity of speech sound disorders in SD or MSD. Conclusion Weak tongue strength does not appear to contribute to speech errors in children with speech sound delays but does appear to be related to speech sound disorders that are neurologic in origin (developmental MSD).
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Affiliation(s)
- Nancy L Potter
- Department of Speech and Hearing Sciences, Washington State University Spokane
| | - Yves Nievergelt
- Department of Mathematics, Eastern Washington University, Cheney
| | - Mark VanDam
- Department of Speech and Hearing Sciences, Washington State University Spokane
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Kwan BCH, McBain RA, Luu BL, Butler JE, Bilston LE, Gandevia SC. Influence of respiratory mechanics and drive on genioglossus movement under ultrasound imaging. PLoS One 2018; 13:e0195884. [PMID: 29659626 PMCID: PMC5901985 DOI: 10.1371/journal.pone.0195884] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 03/30/2018] [Indexed: 11/18/2022] Open
Abstract
METHODS Twenty healthy subjects (10 males, age 28±5 years [mean ± SD]) lay supine, awake, with the head in a neutral position. Ventilation was monitored with inductance bands. Real-time B-mode ultrasound movies were analysed. We measured genioglossus motion (i) during spontaneous breathing, voluntary targeted breathing (normal tidal volume Vt), and voluntary hyperpnoea (at 1.5Vt and 2 Vt); (ii) during inspiratory flow resistive loading; (iii) with changes in end-expiratory lung volume (EELV). RESULTS Average peak inspiratory displacement of the infero-posterior region of genioglossus was 0.89±0.56 mm; 1.02±0.88 mm; 1.27±0.70 mm respectively for voluntary Vt, and during voluntary hyperpnoea at 1.5Vt and 2Vt. A change in genioglossus motion was observed with increased Vt. During increasing inspiratory resistive loading, the genioglossus displaced less anteriorly (p = 0.005) but more inferiorly (p = 0.027). When lung volume was altered, no significant changes in genioglossus movement were observed (p = 0.115). CONCLUSION In healthy subjects, we observed non-uniform heterogeneous inspiratory motion within the inferoposterior part of genioglossus during spontaneous quiet breathing with mean peak displacement between 0.5-2 mm, with more displacement in the posterior region than the anterior. This regional heterogeneity disappeared during voluntary targeted breathing. This may be due to different neural drive to genioglossus during voluntary breathing. During inspiratory resistive loading, the observed genioglossus motion may serve to maintain upper airway patency by balancing intraluminal negative pressure with positive pressure generated by upper airway dilatory muscles. In contrast, changes in EELV were not accompanied by major changes in genioglossus motion.
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Affiliation(s)
- Benjamin C. H. Kwan
- Neuroscience Research Australia (NeuRA), Barker St, Sydney, NSW, Australia
- Prince of Wales Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
- * E-mail:
| | - Rachel A. McBain
- Neuroscience Research Australia (NeuRA), Barker St, Sydney, NSW, Australia
| | - Billy L. Luu
- Neuroscience Research Australia (NeuRA), Barker St, Sydney, NSW, Australia
| | - Jane E. Butler
- Neuroscience Research Australia (NeuRA), Barker St, Sydney, NSW, Australia
| | - Lynne E. Bilston
- Neuroscience Research Australia (NeuRA), Barker St, Sydney, NSW, Australia
- Prince of Wales Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Simon C. Gandevia
- Neuroscience Research Australia (NeuRA), Barker St, Sydney, NSW, Australia
- Prince of Wales Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
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Tsabari R, Daum H, Kerem E, Fellig Y, Dor T. Congenital myopathy due to myosin heavy chain 2 mutation presenting as chronic aspiration pneumonia in infancy. Neuromuscul Disord 2017; 27:947-950. [PMID: 28729039 DOI: 10.1016/j.nmd.2017.06.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 05/24/2017] [Accepted: 06/19/2017] [Indexed: 12/16/2022]
Abstract
A 7-week-old infant presented with persistent noisy breathing and aspirations during swallowing. Neurological examination and brain MRI were normal. His 12-year-old brother underwent pneumonectomy at the age of 10 years due to recurrent aspirations leading to severe lung damage. The older brother developed subsequently ophthalmoplegia and nystagmus along with mild weakness of the neck flexors and proximal muscles. Exome analysis revealed homozygosity for a novel truncating mutation p.G800fs27* in the Myosin Heavy Chain 2 (MYH2) gene in both brothers, while parents and an unaffected sibling were heterozygous. A muscle biopsy from the older brother showed absence of type-2 muscle fibers and predominance of type-1 fibers. The aspirations causing pneumonia likely result from weakness of the laryngeal muscles, normally rich in type-2 fibers. The findings expand the phenotypic spectrum of MYH2 deficiency. MYH2 mutations should be included in the differential diagnosis of infants presenting with recurrent aspirations.
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Affiliation(s)
- R Tsabari
- Department of Pediatrics, Pediatric Pulmonology and Cystic Fibrosis Center, Hadassah-Hebrew University Medical Center Jerusalem, Israel
| | - H Daum
- Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center Jerusalem, Israel
| | - E Kerem
- Department of Pediatrics, Pediatric Pulmonology and Cystic Fibrosis Center, Hadassah-Hebrew University Medical Center Jerusalem, Israel
| | - Y Fellig
- Department of Pathology, Hadassah-Hebrew-University-Medical-Center Jerusalem, Israel
| | - T Dor
- Neuropediatric Unit, Hadassah-Hebrew University Medical Center Jerusalem, Israel.
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Sokoloff AJ, Douglas M, Rahnert JA, Burkholder T, Easley KA, Luo Q. Absence of morphological and molecular correlates of sarcopenia in the macaque tongue muscle styloglossus. Exp Gerontol 2016; 84:40-48. [PMID: 27566374 DOI: 10.1016/j.exger.2016.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 08/18/2016] [Accepted: 08/22/2016] [Indexed: 01/06/2023]
Abstract
INTRODUCTION Equivocal decline of tongue muscle performance with age is compatible with resistance of the tongue to sarcopenia, the loss of muscle volume and function that typically occurs with aging. To test this possibility we characterized anatomical and molecular indices of sarcopenia in the macaque tongue muscle styloglossus (SG). METHODS We quantified myosin heavy chain (MHC), muscle fiber MHC phenotype and size and total and phosphorylated growth- and atrophy-related proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), immunoblot and immunohistochemistry (IHC) in the SG in twenty-four macaque monkeys (Macaca rhesus, age range 9months to 31years) categorized into Young (<8years of age), Middle-aged (15-21years of age) and Old (>22years of age) groups. RESULTS In Young, Middle and Old age groups, by SDS-PAGE MHCI comprised ~1/3 and MHCII ~2/3 of total MHC. MHCI relative frequency was lower and MHCII higher in Middle versus Young (p=0.0099) and Middle versus Old (p=0.052). Relative frequencies of MHC fiber phenotype were not different by age but were different by phenotype (rates 233, 641 and 111 per 1000 fibers for MHCI, MHCII and MHCI-II respectively, p=0.03). Few or no fibers were positive for developmental MHC. Mean cross-sectional area (CSA) was not different among the three age groups for MHCII and MHCI-II; however MHCI fibers tended to be larger in Middle versus Old and Young (mean=2257μm2,1917μm2 (p=0.05) and 1704μm2 (p=0.06), respectively). For each age group, mean CSA increased across MHC phenotype (lowest mean CSA for MHCI and highest mean CSA for MHCII). Spearman analysis demonstrated age-related increases in total p70 ribosomal protein S6 kinase (P70), phosphorylated P70421/424, phosphorylated P38 mitogen-activated protein kinase and muscle atrophy F-Box, a trend to age-related decrease in total extracellular signal-regulated kinase (ERK), and no age-related change in total protein kinase B (Akt/PKB), phosphorylated Akt, phosphorylated ERK, phosphorylated c-Jun N-terminal kinase (JNK46) and phosphorylated P70389. CONCLUSION Common anatomical and molecular indices of sarcopenia are absent in our sample of macaque SG. Relative frequencies of MHCII protein and phenotype are preserved with age. Although MAFbx expression increases with age, this is not associated with fiber atrophy, perhaps reflecting compensatory growth signaling by p70. The resistant nature of the styloglossus muscle to sarcopenia may be related to routine activation of tongue muscles in respiration and swallowing and the preservation of hypoglossal motoneuron number with age.
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Affiliation(s)
- Alan J Sokoloff
- Department of Physiology, Emory University School of Medicine, Atlanta, GA, United States.
| | - Megan Douglas
- Department of Physiology, Emory University School of Medicine, Atlanta, GA, United States
| | - Jill A Rahnert
- School of Applied Physiology, Georgia Institute of Technology, Atlanta, GA, United States
| | - Thomas Burkholder
- School of Applied Physiology, Georgia Institute of Technology, Atlanta, GA, United States
| | - Kirk A Easley
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Qingwei Luo
- Department of Physiology, Emory University School of Medicine, Atlanta, GA, United States
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Kent RD. Nonspeech Oral Movements and Oral Motor Disorders: A Narrative Review. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2015; 24:763-89. [PMID: 26126128 PMCID: PMC4698470 DOI: 10.1044/2015_ajslp-14-0179] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 04/02/2015] [Accepted: 06/13/2015] [Indexed: 05/25/2023]
Abstract
PURPOSE Speech and other oral functions such as swallowing have been compared and contrasted with oral behaviors variously labeled quasispeech, paraspeech, speechlike, and nonspeech, all of which overlap to some degree in neural control, muscles deployed, and movements performed. Efforts to understand the relationships among these behaviors are hindered by the lack of explicit and widely accepted definitions. This review article offers definitions and taxonomies for nonspeech oral movements and for diverse speaking tasks, both overt and covert. METHOD Review of the literature included searches of Medline, Google Scholar, HighWire Press, and various online sources. Search terms pertained to speech, quasispeech, paraspeech, speechlike, and nonspeech oral movements. Searches also were carried out for associated terms in oral biology, craniofacial physiology, and motor control. RESULTS AND CONCLUSIONS Nonspeech movements have a broad spectrum of clinical applications, including developmental speech and language disorders, motor speech disorders, feeding and swallowing difficulties, obstructive sleep apnea syndrome, trismus, and tardive stereotypies. The role and benefit of nonspeech oral movements are controversial in many oral motor disorders. It is argued that the clinical value of these movements can be elucidated through careful definitions and task descriptions such as those proposed in this review article.
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Affiliation(s)
- Ray D. Kent
- Waisman Center, University of Wisconsin–Madison
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10
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Vranish JR, Bailey EF. A comprehensive assessment of genioglossus electromyographic activity in healthy adults. J Neurophysiol 2015; 113:2692-9. [PMID: 25695653 DOI: 10.1152/jn.00975.2014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 02/12/2015] [Indexed: 12/23/2022] Open
Abstract
The genioglossus (GG) is an extrinsic muscle of the human tongue that plays a critical role in preserving airway patency. In the last quarter century, >50 studies have reported on respiratory-related GG electromyographic (EMG) activity in human subjects. Remarkably, of the studies performed, none have duplicated subject body position, electrode recording locations, and/or breathing task(s), making interpretation and integration of the results across studies extremely challenging. In addition, more recent research assessing lingual anatomy and muscle contractile properties has identified regional differences in muscle fiber type and myosin heavy chain expression, giving rise to the possibility that the anterior and posterior regions of the muscle fulfill distinct functions. Here, we assessed EMG activity in anterior and posterior regions of the GG, across upright and supine, in rest breathing and in volitionally modulated breathing tasks. We tested the hypotheses that GG EMG is greater in the posterior region and in supine, except when breathing is subject to volitional modulation. Our results show differences in the magnitude of EMG (%regional maximum) between anterior and posterior muscle regions (7.95 ± 0.57 vs. 11.10 ± 0.99, respectively; P < 0.001), and between upright and supine (8.63 ± 0.73 vs. 10.42 ± 0.90, respectively; P = 0.008). Although the nature of a task affects the magnitude of EMG (P < 0.001), the effect is similar for anterior and posterior muscle regions and across upright and supine (P > 0.2).
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Affiliation(s)
- Jennifer R Vranish
- Department of Physiology, College of Medicine, University of Arizona, Tucson, Arizona
| | - E Fiona Bailey
- Department of Physiology, College of Medicine, University of Arizona, Tucson, Arizona
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Luo Q, Douglas M, Burkholder T, Sokoloff AJ. Absence of developmental and unconventional myosin heavy chain in human suprahyoid muscles. Muscle Nerve 2014; 49:534-44. [PMID: 23835800 DOI: 10.1002/mus.23946] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 06/25/2013] [Accepted: 06/27/2013] [Indexed: 11/07/2022]
Abstract
INTRODUCTION Contradictory reports of the myosin heavy chain (MHC) composition of adult human suprahyoid muscles leave unresolved the extent to which these muscles express developmental and unconventional MHC. METHODS By immunohistochemistry, separation sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-Coomassie, separation SDS-PAGE-Western blot, and mRNA PCR, we tested for conventional MHCI, MHCIIA, MHCIIX, developmental MHC embryonic and MHC neonatal, and unconventional MHC alpha-cardiac, MHC extraocular, and MHC slow tonic in adult human anterior digastric (AD), geniohyoid (GH), and mylohyoid (MH) muscles. RESULTS By separation SDS-PAGE-Coomassie and Western blot, only conventional MHC are present. By immunohistochemistry all muscle fibers are positive for MHCI, MHCIIA, or MHCIIX, and fewer than 4 fibers/mm(2) are positive for developmental or unconventional MHC. By PCR, mRNA of MHCI and MHCIIA dominate, with sporadically detectable MHC alpha-cardiac and without detectable mRNA of other developmental and unconventional MHC. CONCLUSIONS We conclude that human suprahyoid muscles AD, GH, and MH are composed almost exclusively of conventional MHC isoforms.
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Affiliation(s)
- Qingwei Luo
- Department of Physiology, Emory University, 615 Michael Street, Atlanta, Georgia, 30322, USA
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12
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D'Amico A, Fattori F, Bellacchio E, Catteruccia M, Servidei S, Bertini E. A new de novo missense mutation in MYH2 expands clinical and genetic findings in hereditary myosin myopathies. Neuromuscul Disord 2013; 23:437-40. [PMID: 23489661 PMCID: PMC3639366 DOI: 10.1016/j.nmd.2013.02.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 02/06/2013] [Accepted: 02/11/2013] [Indexed: 11/30/2022]
Abstract
Congenital myopathy related to mutations in myosin MyHC IIa gene (MYH2) is a rare neuromuscular disease. A single dominant missense mutation has been reported so far in a family in which the affected members had congenital joint contractures at birth, external ophthalmoplegia and proximal muscle weakness. Afterward only additional 4 recessive mutations have been identified in 5 patients presenting a mild non-progressive early-onset myopathy associated with ophthalmoparesis. We report a new de novo MYH2 missense mutation in a baby affected by a congenital myopathy characterized by severe dysphagia, respiratory distress at birth and external ophthalmoplegia. We describe clinical, histopathological and muscle imaging findings expanding the clinical and genetic spectrum of MYH2-related myopathy.
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Affiliation(s)
- A D'Amico
- Laboratory of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
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Kletzien H, Russell JA, Leverson GE, Connor NP. Differential effects of targeted tongue exercise and treadmill running on aging tongue muscle structure and contractile properties. J Appl Physiol (1985) 2012; 114:472-81. [PMID: 23264540 DOI: 10.1152/japplphysiol.01370.2012] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Age-associated changes in tongue muscle structure and strength may contribute to dysphagia in elderly people. Tongue exercise is a current treatment option. We hypothesized that targeted tongue exercise and nontargeted exercise that activates tongue muscles as a consequence of increased respiratory drive, such as treadmill running, are associated with different patterns of tongue muscle contraction and genioglossus (GG) muscle biochemistry. Thirty-one young adult, 34 middle-aged, and 37 old Fischer 344/Brown Norway rats received either targeted tongue exercise, treadmill running, or no exercise (5 days/wk for 8 wk). Protrusive tongue muscle contractile properties and myosin heavy chain (MHC) composition in the GG were examined at the end of 8 wk across groups. Significant age effects were found for maximal twitch and tetanic tension (greatest in young adult rats), MHCIIb (highest proportion in young adult rats), MHCIIx (highest proportion in middle-aged and old rats), and MHCI (highest proportion in old rats). The targeted tongue exercise group had the greatest maximal twitch tension and the highest proportion of MHCI. The treadmill running group had the shortest half-decay time, the lowest proportion of MHCIIa, and the highest proportion of MHCIIb. Fatigue was significantly less in the young adult treadmill running group and the old targeted tongue exercise group than in other groups. Thus, tongue muscle structure and contractile properties were affected by both targeted tongue exercise and treadmill running, but in different ways. Studies geared toward optimizing dose and manner of providing targeted and generalized tongue exercise may lead to alternative tongue exercise delivery strategies.
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Affiliation(s)
- Heidi Kletzien
- Department of Surgery, Otolaryngology-Head and Neck Surgery, University of Wisconsin, Madison, Wisconsin, USA
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Saboisky JP, Butler JE, Gandevia SC, Eckert DJ. Functional role of neural injury in obstructive sleep apnea. Front Neurol 2012; 3:95. [PMID: 22715333 PMCID: PMC3375463 DOI: 10.3389/fneur.2012.00095] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 05/28/2012] [Indexed: 12/31/2022] Open
Abstract
The causes of obstructive sleep apnea (OSA) are multifactorial. Neural injury affecting the upper airway muscles due to repetitive exposure to intermittent hypoxia and/or mechanical strain resulting from snoring and recurrent upper airway closure have been proposed to contribute to OSA disease progression. Multiple studies have demonstrated altered sensory and motor function in patients with OSA using a variety of neurophysiological and histological approaches. However, the extent to which the alterations contribute to impairments in upper airway muscle function, and thus OSA disease progression, remains uncertain. This brief review, primarily focused on data in humans, summarizes: (1) the evidence for upper airway sensorimotor injury in OSA and (2) current understanding of how these changes affect upper airway function and their potential to change OSA progression. Some unresolved questions including possible treatment targets are noted.
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