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Lin PC, Chen CH, Chang JH, Peng CC, Jim WT, Lin CY, Hsu CH, Chang HY. Monitoring of the Healthy Neonatal Transition Period with Serial Lung Ultrasound. CHILDREN (BASEL, SWITZERLAND) 2023; 10:1307. [PMID: 37628306 PMCID: PMC10453359 DOI: 10.3390/children10081307] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 07/24/2023] [Accepted: 07/27/2023] [Indexed: 08/27/2023]
Abstract
Ultrasound has been used to observe lung aeration and fluid clearance during the neonatal transition period, but there is no consensus regarding the optimal timing of lung ultrasound. We aimed to monitor the trend of the serial lung ultrasound score (LUS) and extended LUS (eLUS) throughout the neonatal transition period (≤1, 2, 4, 8, 24, and 48 h after birth), assess any correlation to the clinical presentation (using the Silverman Andersen Respiratory Severity Score (RSS)), and determine the optimal time of the ultrasound. We found both LUS and eLUS decreased significantly after 2 h of life and had similar statistical differences among the serial time points. Although both scores had a positive, moderate correlation to the RSS overall (Pearson correlation 0.499 [p < 0.001] between LUS and RSS, 0.504 [p < 0.001] between eLUS and RSS), the correlation was poor within 1 h of life (Pearson correlation 0.15 [p = 0.389] between LUS and RSS, 0.099 [p = 0.573] between eLUS and RSS). For better clinical correlation, the first lung ultrasound for the neonate may be performed at 2 h of life. Further research is warranted to explore the clinical value and limitations of earlier (≤1 h of life) lung ultrasound examinations.
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Affiliation(s)
- Po-Chih Lin
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
| | - Chia-Huei Chen
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
| | - Jui-Hsing Chang
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
- Department of Medicine, MacKay Medical College, New Taipei City 25245, Taiwan
| | - Chun-Chih Peng
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
- Department of Medicine, MacKay Medical College, New Taipei City 25245, Taiwan
| | - Wai-Tim Jim
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
- Department of Medicine, MacKay Medical College, New Taipei City 25245, Taiwan
| | - Chia-Ying Lin
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
| | - Chyong-Hsin Hsu
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
| | - Hung-Yang Chang
- Department of Pediatrics, MacKay Children’s Hospital, Taipei 104217, Taiwan; (P.-C.L.); (W.-T.J.)
- Department of Medicine, MacKay Medical College, New Taipei City 25245, Taiwan
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2
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Muacevic A, Adler JR. Effects of Pollution on Pregnancy and Infants. Cureus 2023; 15:e33906. [PMID: 36819435 PMCID: PMC9937639 DOI: 10.7759/cureus.33906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/18/2023] [Indexed: 01/20/2023] Open
Abstract
The fetus is particularly susceptible to environmental contaminants as it is developing at the time of pregnancy and is, therefore, more susceptible to their effects. Pregnancy loss, which includes stillbirth and spontaneous abortion (miscarriage), preterm labor and delivery, and neonatal death, is the worst pregnancy outcome. Stunting and its related health and developmental effects are particularly common in populations living in underdeveloped countries or those exposed to high levels of particle pollution. Several environmental toxins can affect an embryo, fetus, or infant as they are developing. This study explores the following questions: What part do pesticides, heavy metals, dioxin derivatives, and polychlorinated diphenyl compounds play as macroenvironmental pollutants in mutagenesis and teratogenesis? What effects do substances that exposed persons have considerable control over, such as alcohol, narcotics, and tobacco smoke, have on the microenvironment? What consequences should practitioners be aware of these toxins in terms of ethics and the law? This study seeks to assess pertinent primary scientific studies on how pollution affects the health of the fetus and newborn during pregnancy.
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3
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Ozdemir F, Acmaz G, Madendag Y, Madendag IC, Muderris II. The effect of steroid administration on fetal diaphragm function. BMC Pregnancy Childbirth 2022; 22:762. [PMID: 36224559 PMCID: PMC9555001 DOI: 10.1186/s12884-022-05074-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 09/16/2022] [Indexed: 11/22/2022] Open
Abstract
Background Antenatal steroid administrations lead to not only accelerated lung maturation, improved blood gas measurements but also lung dynamics and lung compliance. This study aimed to investigate structural and functional changes in diaphragm after antenatal steroid administration. Methods The 79 volunteers were divided into 2 groups according to presence of preterm delivery. Betamethasone (CelestoneR) 12 mg intramuscularly was routinely administered to pregnancies complicated with preterm delivery between 28th -34th weeks of gestation. Same dose was repeated 24 h later. In all patients, diaphragm thickness, diaphragmatic excursion and costophrenic angle were measured in both the inspirium and expirium stage of respiration. This is an observational cross-sectional study. Results Diaphragm thickness, diaphragmatic excursion and diaphragm thickening fraction parameters were improved but costophrenic angle was not different 7 days after steroid administration. Diaphragm thickness, diaphragmatic excursion and costophrenic angle changes during inspiration and expiration stage after 7 days of betamethasone treatment reflects the effect of steroid administration on diaphragm muscle. Comparisons of the differences that occur after steroid rescue protocol were done by subtracting the diaphragm thickness, diaphragmatic excursion and costophrenic angle parameters before the treatment from the diaphragm thickness, diaphragmatic excursion and costophrenic angle parameters 7 days after steroid treatment respectively. Conclusion Diaphragm became more mobile in patients with preterm labor, 7 days after steroid administration. This situation reflects positive effect of steroid administration on diaphragm function.
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Affiliation(s)
- Fatma Ozdemir
- Department of Obstetrics and Gynecology, Erciyes University Faculty of Medicine, Yenidogan District, Turhan Baytop Street No:1, 38280, Kayseri, Melikgazi Kayseri, Turkey
| | - Gokhan Acmaz
- Department of Obstetrics and Gynecology, Erciyes University Faculty of Medicine, Yenidogan District, Turhan Baytop Street No:1, 38280, Kayseri, Melikgazi Kayseri, Turkey.
| | - Yusuf Madendag
- Department of Obstetrics and Gynecology, Erciyes University Faculty of Medicine, Yenidogan District, Turhan Baytop Street No:1, 38280, Kayseri, Melikgazi Kayseri, Turkey
| | - Ilknur Col Madendag
- Obstetrics and Gynecology Department, Kayseri City Hospital, Kayseri, Turkey
| | - Iptisam Ipek Muderris
- Department of Obstetrics and Gynecology, Erciyes University Faculty of Medicine, Yenidogan District, Turhan Baytop Street No:1, 38280, Kayseri, Melikgazi Kayseri, Turkey
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4
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Dahl MJ, Lavizzari A, Davis JW, Noble PB, Dellacà R, Pillow JJ. Impact of fetal treatments for congenital diaphragmatic hernia on lung development. Anat Rec (Hoboken) 2022. [PMID: 36065499 DOI: 10.1002/ar.25059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/26/2022] [Accepted: 08/08/2022] [Indexed: 11/10/2022]
Abstract
The extent of lung hypoplasia impacts the survival and severity of morbidities associated with congenital diaphragmatic hernia (CDH). The alveoli of CDH infants and in experimental models of CDH have thickened septa with fewer type II pneumocytes and capillaries. Fetal treatments of CDH-risk preterm birth. Therefore, treatments must aim to balance the need for increased gas exchange surface area with the restoration of pulmonary epithelial type II cells and the long-term respiratory and neurodevelopmental consequences of prematurity. Achievement of sufficient lung development in utero for successful postnatal transition requires adequate intra-thoracic space for lung growth, maintenance of sufficient volume and appropriate composition of fetal lung fluid, regular fetal breathing movements, appropriate gas exchange area, and ample surfactant production. The review aims to examine the rationale for current and future therapeutic strategies to improve postnatal outcomes of infants with CDH.
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Affiliation(s)
- Mar Janna Dahl
- School of Human Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Anna Lavizzari
- NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Jonathan W Davis
- Medical School, University of Western Australia, Perth, Western Australia, Australia
- Telethon Kids Institute, Perth Children's Hospital, Perth, Western Australia, Australia
| | - Peter B Noble
- School of Human Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Raffaele Dellacà
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano University, Milan, Italy
| | - J Jane Pillow
- School of Human Sciences, University of Western Australia, Perth, Western Australia, Australia
- Telethon Kids Institute, Perth Children's Hospital, Perth, Western Australia, Australia
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Veerati PC, Mitchel JA, Reid AT, Knight DA, Bartlett NW, Park JA, Grainge CL. Airway mechanical compression: its role in asthma pathogenesis and progression. Eur Respir Rev 2020; 29:190123. [PMID: 32759373 PMCID: PMC8008491 DOI: 10.1183/16000617.0123-2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/30/2020] [Indexed: 12/22/2022] Open
Abstract
The lung is a mechanically active organ, but uncontrolled or excessive mechanical forces disrupt normal lung function and can contribute to the development of disease. In asthma, bronchoconstriction leads to airway narrowing and airway wall buckling. A growing body of evidence suggests that pathological mechanical forces induced by airway buckling alone can perpetuate disease processes in asthma. Here, we review the data obtained from a variety of experimental models, including in vitro, ex vivo and in vivo approaches, which have been used to study the impact of mechanical forces in asthma pathogenesis. We review the evidence showing that mechanical compression alters the biological and biophysical properties of the airway epithelium, including activation of the epidermal growth factor receptor pathway, overproduction of asthma-associated mediators, goblet cell hyperplasia, and a phase transition of epithelium from a static jammed phase to a mobile unjammed phase. We also define questions regarding the impact of mechanical forces on the pathology of asthma, with a focus on known triggers of asthma exacerbations such as viral infection.
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Affiliation(s)
- Punnam Chander Veerati
- School of Medicine and Public Health, University of Newcastle, Callaghan, Australia
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, New Lambton Heights, Australia
| | - Jennifer A Mitchel
- Molecular and Integrative Physiological Sciences Program, Dept of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Andrew T Reid
- School of Medicine and Public Health, University of Newcastle, Callaghan, Australia
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, New Lambton Heights, Australia
| | - Darryl A Knight
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, New Lambton Heights, Australia
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, Australia
- Dept of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, Canada
- Research and Academic Affairs, Providence Health Care Research Institute, Vancouver, Canada
| | - Nathan W Bartlett
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, New Lambton Heights, Australia
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, Australia
| | - Jin-Ah Park
- Molecular and Integrative Physiological Sciences Program, Dept of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Chris L Grainge
- School of Medicine and Public Health, University of Newcastle, Callaghan, Australia
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, New Lambton Heights, Australia
- Dept of Respiratory and Sleep Medicine, John Hunter Hospital, Newcastle, Australia
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6
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Abstract
This review focuses on the use of veno-venous extracorporeal membrane oxygenation for respiratory failure across all blood flow ranges. Starting with a short overview of historical development, aspects of the physiology of gas exchange (i.e., oxygenation and decarboxylation) during extracorporeal circulation are discussed. The mechanisms of phenomena such as recirculation and shunt playing an important role in daily clinical practice are explained.Treatment of refractory and symptomatic hypoxemic respiratory failure (e.g., acute respiratory distress syndrome [ARDS]) currently represents the main indication for high-flow veno-venous-extracorporeal membrane oxygenation. On the other hand, lower-flow extracorporeal carbon dioxide removal might potentially help to avoid or attenuate ventilator-induced lung injury by allowing reduction of the energy load (i.e., driving pressure, mechanical power) transmitted to the lungs during mechanical ventilation or spontaneous ventilation. In the latter context, extracorporeal carbon dioxide removal plays an emerging role in the treatment of chronic obstructive pulmonary disease patients during acute exacerbations. Both applications of extracorporeal lung support raise important ethical considerations, such as likelihood of ultimate futility and end-of-life decision-making. The review concludes with a brief overview of potential technical developments and persistent challenges.
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7
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Beyeler SA, Hodges MR, Huxtable AG. Impact of inflammation on developing respiratory control networks: rhythm generation, chemoreception and plasticity. Respir Physiol Neurobiol 2020; 274:103357. [PMID: 31899353 DOI: 10.1016/j.resp.2019.103357] [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: 07/31/2019] [Revised: 11/17/2019] [Accepted: 12/02/2019] [Indexed: 10/25/2022]
Abstract
The respiratory control network in the central nervous system undergoes critical developmental events early in life to ensure adequate breathing at birth. There are at least three "critical windows" in development of respiratory control networks: 1) in utero, 2) newborn (postnatal day 0-4 in rodents), and 3) neonatal (P10-13 in rodents, 2-4 months in humans). During these critical windows, developmental processes required for normal maturation of the respiratory control network occur, thereby increasing vulnerability of the network to insults, such as inflammation. Early life inflammation (induced by LPS, chronic intermittent hypoxia, sustained hypoxia, or neonatal maternal separation) acutely impairs respiratory rhythm generation, chemoreception and increases neonatal risk of mortality. These early life impairments are also greater in young males, suggesting sex-specific impairments in respiratory control. Further, neonatal inflammation has a lasting impact on respiratory control by impairing adult respiratory plasticity. This review focuses on how inflammation alters respiratory rhythm generation, chemoreception and plasticity during each of the three critical windows. We also highlight the need for additional mechanistic studies and increased investigation into how glia (such as microglia and astrocytes) play a role in impaired respiratory control after inflammation. Understanding how inflammation during critical windows of development disrupt respiratory control networks is essential for developing better treatments for vulnerable neonates and preventing adult ventilatory control disorders.
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Affiliation(s)
- Sarah A Beyeler
- Department of Human Physiology, University of Oregon, Eugene, OR, 97403, United States
| | - Matthew R Hodges
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Adrianne G Huxtable
- Department of Human Physiology, University of Oregon, Eugene, OR, 97403, United States.
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8
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Heise RL, Link PA, Farkas L. From Here to There, Progenitor Cells and Stem Cells Are Everywhere in Lung Vascular Remodeling. Front Pediatr 2016; 4:80. [PMID: 27583245 PMCID: PMC4988064 DOI: 10.3389/fped.2016.00080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 07/20/2016] [Indexed: 01/27/2023] Open
Abstract
The field of stem cell biology, cell therapy, and regenerative medicine has expanded almost exponentially, in the last decade. Clinical trials are evaluating the potential therapeutic use of stem cells in many adult and pediatric lung diseases with vascular component, such as bronchopulmonary dysplasia (BPD), chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), or pulmonary arterial hypertension (PAH). Extensive research activity is exploring the lung resident and circulating progenitor cells and their contribution to vascular complications of chronic lung diseases, and researchers hope to use resident or circulating stem/progenitor cells to treat chronic lung diseases and their vascular complications. It is becoming more and more clear that progress in mechanobiology will help to understand the various influences of physical forces and extracellular matrix composition on the phenotype and features of the progenitor cells and stem cells. The current review provides an overview of current concepts in the field.
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Affiliation(s)
- Rebecca L Heise
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University , Richmond, VA , USA
| | - Patrick A Link
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University , Richmond, VA , USA
| | - Laszlo Farkas
- Department of Internal Medicine, Division of Pulmonary Disease and Critical Care Medicine, School of Medicine, Virginia Commonwealth University , Richmond, VA , USA
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9
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Hooper SB, Polglase GR, Roehr CC. Cardiopulmonary changes with aeration of the newborn lung. Paediatr Respir Rev 2015; 16:147-50. [PMID: 25870083 PMCID: PMC4526381 DOI: 10.1016/j.prrv.2015.03.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 03/12/2015] [Indexed: 10/23/2022]
Abstract
The newborn's transition from fetal to neonatal life includes aeration of the lungs, establishment of pulmonary gas exchange and changing the fetal circulation into the adult phenotype. This review summarizes the latest research findings, which show that lung aeration, airway liquid clearance and cardiovascular changes are directly interconnected at birth. The mechanisms of airway liquid clearance at birth are reviewed and the particular importance of the transpulmonary pressure gradient during lung aeration is discussed. Further, we summarize research findings which prove that lung aeration triggers the increase in pulmonary blood flow (PBF) at birth, and how the increase in PBF secures the preload for left ventricular output. Consequently, we review animal experiments which suggest that delaying umbilical cord clamping until breathing commences facilitates hemodynamic stability during transition. These data are reviewed with respect to the clinical applicability: As lung aeration is the key to successful transition to newborn life, providing adequate respiratory support at birth must be the primary objective of neonatal staff attending to the newborn infant. Clinical studies are needed to demonstrate whether the obvious benefits of delaying cord clamping until breathing commences hold true in human babies.
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Affiliation(s)
- Stuart Brian Hooper
- The Ritchie Centre, MIMR-PHI Institute of Medical Research, Melbourne, Australia; Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia.
| | - Graeme Roger Polglase
- The Ritchie Centre, MIMR-PHI Institute of Medical Research, Melbourne, Australia, Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Charles Christoph Roehr
- The Ritchie Centre, MIMR-PHI Institute of Medical Research, Melbourne, Australia, Newborn Services, John Radcliffe Hospital, Oxford University Hospitals, Oxford, United Kingdom, Dept. Neonatology, Charité University Medical Centre, Berlin, Germany
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10
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Sanchez-Esteban J. Mechanical forces in fetal lung development: opportunities for translational research. Front Pediatr 2013; 1:51. [PMID: 24400295 PMCID: PMC3872295 DOI: 10.3389/fped.2013.00051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 12/11/2013] [Indexed: 12/29/2022] Open
Affiliation(s)
- Juan Sanchez-Esteban
- Department of Pediatrics, Alpert Medical School of Brown University , Providence, RI , USA
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11
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Abstract
Breathing movements have been demonstrated in the fetuses of every mammalian species investigated and are a critical component of normal fetal development. The classic sheep preparations instrumented for chronic fetal monitoring determined that fetal breathing movements (FBMs) occur in aggregates interspersed with long periods of quiescence that are strongly associated with neurophysiological state. The fetal sheep model also provided data regarding the neurochemical modulation of behavioral state and FBMs under a variety of in utero conditions. Subsequently, in vitro rodent models have been developed to advance our understanding of cellular, synaptic, network, and more detailed neuropharmacological aspects of perinatal respiratory neural control. This includes the ontogeny of the inspiratory rhythm generating center, the preBötzinger complex (preBötC), and the anatomical and functional development of phrenic motoneurons (PMNs) and diaphragm during the perinatal period. A variety of newborn animal models and studies of human infants have provided insights into age-dependent changes in state-dependent respiratory control, responses to hypoxia/hypercapnia and respiratory pathologies.
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Affiliation(s)
- John J Greer
- Department of Physiology, Centre for Neuroscience, Women and Children Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
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12
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Stocks J, Hislop A, Sonnappa S. Early lung development: lifelong effect on respiratory health and disease. THE LANCET RESPIRATORY MEDICINE 2013; 1:728-42. [PMID: 24429276 DOI: 10.1016/s2213-2600(13)70118-8] [Citation(s) in RCA: 236] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Interest in the contribution of changes in lung development during early life to subsequent respiratory morbidity is increasing. Most evidence of an association between adverse intrauterine factors and structural effects on the developing lung is from animal studies. Such evidence has been augmented by epidemiological studies showing associations between insults to the developing lung during prenatal and early postnatal life and adult respiratory morbidity or reduced lung function, and by physiological studies that have elucidated mechanisms underlying these associations. The true effect of early insults on subsequent respiratory morbidity can be understood only if the many prenatal and postnatal factors that can affect lung development are taken into account. Adverse factors affecting lung development during fetal life and early childhood reduce the attainment of maximum lung function and accelerate lung function decline in adulthood, initiating or worsening morbidity in susceptible individuals. In this Review, we focus on factors that adversely affect lung development in utero and during the first 5 years after birth, thereby predisposing individuals to reduced lung function and increased respiratory morbidity throughout life. We focus particularly on asthma and COPD.
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Affiliation(s)
- Janet Stocks
- University College London, Institute of Child Health, London, UK.
| | - Alison Hislop
- University College London, Institute of Child Health, London, UK
| | - Samatha Sonnappa
- University College London, Institute of Child Health, London, UK
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13
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Stocks J, Sonnappa S. Early life influences on the development of chronic obstructive pulmonary disease. Ther Adv Respir Dis 2013; 7:161-73. [PMID: 23439689 PMCID: PMC4107852 DOI: 10.1177/1753465813479428] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
There is increasing evidence that chronic obstructive pulmonary disease (COPD) is not simply a disease of old age that is largely restricted to heavy smokers, but may be associated with insults to the developing lung during foetal life and the first few years of postnatal life, when lung growth and development are rapid. A better understanding of the long-term effects of early life factors, such as intrauterine growth restriction, prenatal and postnatal exposure to tobacco smoke and other pollutants, preterm delivery and childhood respiratory illnesses, on the subsequent development of chronic respiratory disease is imperative if appropriate preventive and management strategies to reduce the burden of COPD are to be developed. The extent to which insults to the developing lung are associated with increased risk of COPD in later life depends on the underlying cause, timing and severity of such derangements. Suboptimal conditions in utero result in aberrations of lung development such that affected individuals are born with reduced lung function, which tends to remain diminished throughout life, thereby increasing the risk both of wheezing disorders during childhood and subsequent COPD in genetically susceptible individuals. If the current trend towards the ever-increasing incidence of COPD is to be reversed, it is essential to minimize risks to the developing lung by improvements in antenatal and neonatal care, and to reduce prenatal and postnatal exposures to environmental pollutants, including passive tobacco smoke. Furthermore, adult physicians need to recognize that lung disease is potentially associated with early life insults and provide better education regarding diet, exercise and avoidance of smoking to preserve precious reserves of lung function in susceptible adults. This review focuses on factors that adversely influence lung development in utero and during the first 5 years of life, thereby predisposing to subsequent COPD.
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Affiliation(s)
- Janet Stocks
- Portex Unit, University College London Institute of Child Health, 30, Guilford Street, London WC1N 1EH, UK.
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14
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Genome-wide ENU mutagenesis in combination with high density SNP analysis and exome sequencing provides rapid identification of novel mouse models of developmental disease. PLoS One 2013; 8:e55429. [PMID: 23469164 PMCID: PMC3585849 DOI: 10.1371/journal.pone.0055429] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 12/22/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Mice harbouring gene mutations that cause phenotypic abnormalities during organogenesis are invaluable tools for linking gene function to normal development and human disorders. To generate mouse models harbouring novel alleles that are involved in organogenesis we conducted a phenotype-driven, genome-wide mutagenesis screen in mice using the mutagen N-ethyl-N-nitrosourea (ENU). METHODOLOGY/PRINCIPAL FINDINGS ENU was injected into male C57BL/6 mice and the mutations transmitted through the germ-line. ENU-induced mutations were bred to homozygosity and G3 embryos screened at embryonic day (E) 13.5 and E18.5 for abnormalities in limb and craniofacial structures, skin, blood, vasculature, lungs, gut, kidneys, ureters and gonads. From 52 pedigrees screened 15 were detected with anomalies in one or more of the structures/organs screened. Using single nucleotide polymorphism (SNP)-based linkage analysis in conjunction with candidate gene or next-generation sequencing (NGS) we identified novel recessive alleles for Fras1, Ift140 and Lig1. CONCLUSIONS/SIGNIFICANCE In this study we have generated mouse models in which the anomalies closely mimic those seen in human disorders. The association between novel mutant alleles and phenotypes will lead to a better understanding of gene function in normal development and establish how their dysfunction causes human anomalies and disease.
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15
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Mammoto A, Mammoto T, Ingber DE. Mechanosensitive mechanisms in transcriptional regulation. J Cell Sci 2012; 125:3061-73. [PMID: 22797927 DOI: 10.1242/jcs.093005] [Citation(s) in RCA: 282] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Transcriptional regulation contributes to the maintenance of pluripotency, self-renewal and differentiation in embryonic cells and in stem cells. Therefore, control of gene expression at the level of transcription is crucial for embryonic development, as well as for organogenesis, functional adaptation, and regeneration in adult tissues and organs. In the past, most work has focused on how transcriptional regulation results from the complex interplay between chemical cues, adhesion signals, transcription factors and their co-regulators during development. However, chemical signaling alone is not sufficient to explain how three-dimensional (3D) tissues and organs are constructed and maintained through the spatiotemporal control of transcriptional activities. Accumulated evidence indicates that mechanical cues, which include physical forces (e.g. tension, compression or shear stress), alterations in extracellular matrix (ECM) mechanics and changes in cell shape, are transmitted to the nucleus directly or indirectly to orchestrate transcriptional activities that are crucial for embryogenesis and organogenesis. In this Commentary, we review how the mechanical control of gene transcription contributes to the maintenance of pluripotency, determination of cell fate, pattern formation and organogenesis, as well as how it is involved in the control of cell and tissue function throughout embryogenesis and adult life. A deeper understanding of these mechanosensitive transcriptional control mechanisms should lead to new approaches to tissue engineering and regenerative medicine.
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Affiliation(s)
- Akiko Mammoto
- Vascular Biology Program, Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
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16
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Waters CM, Roan E, Navajas D. Mechanobiology in lung epithelial cells: measurements, perturbations, and responses. Compr Physiol 2012; 2:1-29. [PMID: 23728969 PMCID: PMC4457445 DOI: 10.1002/cphy.c100090] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Epithelial cells of the lung are located at the interface between the environment and the organism and serve many important functions including barrier protection, fluid balance, clearance of particulate, initiation of immune responses, mucus and surfactant production, and repair following injury. Because of the complex structure of the lung and its cyclic deformation during the respiratory cycle, epithelial cells are exposed to continuously varying levels of mechanical stresses. While normal lung function is maintained under these conditions, changes in mechanical stresses can have profound effects on the function of epithelial cells and therefore the function of the organ. In this review, we will describe the types of stresses and strains in the lungs, how these are transmitted, and how these may vary in human disease or animal models. Many approaches have been developed to better understand how cells sense and respond to mechanical stresses, and we will discuss these approaches and how they have been used to study lung epithelial cells in culture. Understanding how cells sense and respond to changes in mechanical stresses will contribute to our understanding of the role of lung epithelial cells during normal function and development and how their function may change in diseases such as acute lung injury, asthma, emphysema, and fibrosis.
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Simpson SJ, Flecknoe SJ, Clugston RD, Greer JJ, Hooper SB, Frappell PB. Structural and functional development of the respiratory system in a newborn marsupial with cutaneous gas exchange. Physiol Biochem Zool 2011; 84:634-49. [PMID: 22030856 DOI: 10.1086/662557] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Marsupials are born with structurally immature lungs and rely, to varying degrees, on cutaneous gas exchange. With a gestation of 13 d and a birth weight of 13 mg, the fat-tailed dunnart (Sminthopsis crassicaudata) is one of the smallest and most immature marsupial newborns. We determined that the skin is almost solely responsible for gas exchange in the early neonatal period. Indeed, fewer than 35% of newborn dunnarts were observed to make any respiratory effort on the day of birth, with pulmonary ventilation alone not meeting the demand for oxygen until approximately 35 d postpartum. Despite the lack of pulmonary ventilation, the phrenic nerve had made contact with the diaphragm, and the respiratory epithelium was sufficiently developed to support gas exchange on the day of birth. Both type I and type II (surfactant-producing) alveolar epithelial cells were present, with fewer than 7% of the cells resembling undifferentiated alveolar epithelial precursor cells. The type I epithelial cells did, however, display thickened cytoplasmic extensions, leading to a high diffusion distance for oxygen. In addition, the architecture of the lung was immature, resembling the early canalicular stage, with alveolarization not commencing until 45 d postpartum. The pulmonary vasculature was also immature, with a centrally positioned single-capillary layer not evident until 100 d postbirth. These structural limitations may impede efficient pulmonary gas exchange, forcing the neonatal fat-tailed dunnart to rely predominately on its skin, a phenomenon supported by a low metabolic rate and small size.
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Affiliation(s)
- Shannon J Simpson
- Adaptational and Evolutionary Respiratory Physiology Laboratory, School of Zoology, University of Tasmania, Hobart, Tasmania 7005, Australia
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Bournival V, Desjardins R, Campbell S, Roberge C, Doueik A, Gendron L, Payet MD, Gallo-Payet N, Day R, Praud JP. Presence of task-1 channel in the laryngeal mucosa in the newborn lamb. Exp Lung Res 2011; 37:205-11. [PMID: 21309733 DOI: 10.3109/01902148.2010.536610] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Nearly 40 potassium channels have been described in respiratory epithelial cells. Of these are found several members of the 4-transmembrane domain, 2-pore K(+) channel family (K2P family), namely Twik-1 and -2, Trek-1 and -2, Task-2, -3, and -4, Thik-1, and KCNK7. The aim of this study was to verify whether the Twik-related acid-sensitive K(+) channel, subtype 1 (Task-1) (also known as KCNK3), is present in the laryngeal mucosa in the newborn lamb. Through the use of immunohistochemistry and nested polymerase chain reaction (PCR) amplification, results indicate that Task-1 protein and mRNA are present in the laryngeal mucosa, in both the ciliated, pseudostratified columnar (respiratory) epithelium and the nonkeratinized, stratified squamous epithelium. The complete ovine Task-1 protein sequence showed high homology levels with previously reported mouse, bovine, and human Task-1 sequences. This includes a complete homology for the C-terminal amino acid sequence, which is mandatory for protein trafficking to the cell membrane. These results represent the first demonstration that Task-1, a pH-sensitive channel responsible for setting membrane potential, is present in the laryngeal mucosa of a newborn mammal.
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Affiliation(s)
- Véronique Bournival
- Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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Baptista V. A qualitative analogy for respiratory mechanics. ADVANCES IN PHYSIOLOGY EDUCATION 2010; 34:239-243. [PMID: 21098394 DOI: 10.1152/advan.00014.2010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Affiliation(s)
- Vander Baptista
- Departamento de Ciências Fisiológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil.
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Abstract
During the development of the pulmonary vasculature in the fetus, many structural and functional changes occur to prepare the lung for the transition to air breathing. The development of the pulmonary circulation is genetically controlled by an array of mitogenic factors in a temporo-spatial order. With advancing gestation, pulmonary vessels acquire increased vasoreactivity. The fetal pulmonary vasculature is exposed to a low oxygen tension environment that promotes high intrinsic myogenic tone and high vasocontractility. At birth, a dramatic reduction in pulmonary arterial pressure and resistance occurs with an increase in oxygen tension and blood flow. The striking hemodynamic differences in the pulmonary circulation of the fetus and newborn are regulated by various factors and vasoactive agents. Among them, nitric oxide, endothelin-1, and prostaglandin I2 are mainly derived from endothelial cells and exert their effects via cGMP, cAMP, and Rho kinase signaling pathways. Alterations in these signaling pathways may lead to vascular remodeling, high vasocontractility, and persistent pulmonary hypertension of the newborn.
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Affiliation(s)
- Yuansheng Gao
- Department of Physiology and Pathophysiology, Peking University, Health Science Center, Beijing, China; and Department of Pediatrics, University of Illinois, College of Medicine at Chicago, Chicago, Illinois
| | - J. Usha Raj
- Department of Physiology and Pathophysiology, Peking University, Health Science Center, Beijing, China; and Department of Pediatrics, University of Illinois, College of Medicine at Chicago, Chicago, Illinois
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21
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Oh WJ, Westmoreland JJ, Summers R, Condie BG. Cleft palate is caused by CNS dysfunction in Gad1 and Viaat knockout mice. PLoS One 2010; 5:e9758. [PMID: 20333300 PMCID: PMC2841638 DOI: 10.1371/journal.pone.0009758] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Accepted: 03/01/2010] [Indexed: 12/22/2022] Open
Abstract
Background Previous studies have shown that disruption of GABA signaling in mice via mutations in the Gad1, Gabrb3 or Viaat genes leads to the development of non-neural developmental defects such as cleft palate. Studies of the Gabrb3 and Gad1 mutant mice have suggested that GABA function could be required either in the central nervous system or in the palate itself for normal palatogenesis. Methodology/Principal Findings To further examine the role of GABA signaling in palatogenesis we used three independent experimental approaches to test whether Gad1 or Viaat function is required in the fetal CNS for normal palate development. We used oral explant cultures to demonstrate that the Gad1 and Viaat mutant palates were able to undergo palatogenesis in culture, suggesting that there is no defect in the palate tissue itself in these mice. In a second series of experiments we found that the GABAA receptor agonist muscimol could rescue the cleft palate phenotype in Gad1 and Viaat mutant embryos. This suggested that normal multimeric GABAA receptors in the CNS were necessary for normal palatogenesis. In addition, we showed that CNS-specific inactivation of Gad1 was sufficient to disrupt palate development. Conclusions/Significance Our results are consistent with a role for Gad1 and Viaat in the central nervous system for normal development of the palate. We suggest that the alterations in GABA signaling lead to non-neural defects such as cleft palate as a secondary effect due to alterations in or elimination of fetal movements.
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Affiliation(s)
- Won-Jong Oh
- Developmental Biology Group, Department of Genetics, University of Georgia, Athens, Georgia, United States of America
- Institute of Molecular Medicine, Medical College of Georgia, Augusta, Georgia, United States of America
| | - Joby J. Westmoreland
- Institute of Molecular Medicine, Medical College of Georgia, Augusta, Georgia, United States of America
| | - Ryan Summers
- Developmental Biology Group, Department of Genetics, University of Georgia, Athens, Georgia, United States of America
| | - Brian G. Condie
- Developmental Biology Group, Department of Genetics, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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22
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Sá-Couto CD, Andriessen P, Van Meurs WL, Ayres-de-Campos D, Sá-Couto PM. A model for educational simulation of hemodynamic transitions at birth. Pediatr Res 2010; 67:158-65. [PMID: 19809380 DOI: 10.1203/pdr.0b013e3181c2def3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Birth is characterized by swift and complex transitions in hemodynamic and respiratory variables. Unrecognized pathologies or incidents may quickly become fatal or cause permanent damage. This article introduces an essential component of an acute perinatal care simulator, namely a model for educational simulation of normal hemodynamic transitions seen during and shortly after birth. We explicitly formulate educational objectives and adapt a preexisting model for the simulation of neonatal cardiovascular physiology to include essential aspects of fetal hemodynamics. From the scientific literature, we obtain model parameters that characterize these aspects quantitatively. The fetal model is controlled by a time- and event-based script of changes occurring at birth, such as onset of breathing and cord clamping, and the transitory phase up to 24 h after birth. Comparison of simulation results with published target data confirms that realistic simulated hemodynamic vital signs are achieved.
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Affiliation(s)
- Carla D Sá-Couto
- INEB-Instituto de Engenharia Biomédica, Porto, 4200-465, Portugal
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23
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Wang Y, Maciejewski BS, Soto-Reyes D, Lee HS, Warburton D, Sanchez-Esteban J. Mechanical stretch promotes fetal type II epithelial cell differentiation via shedding of HB-EGF and TGF-alpha. J Physiol 2009; 587:1739-53. [PMID: 19237431 DOI: 10.1113/jphysiol.2008.163899] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The mechanisms by which mechanical forces promote fetal lung development are not fully understood. Here, we investigated differentiation of fetal type II epithelial cells via the epidermal growth factor receptor (EGFR) in response to mechanical strain. First, we showed that incubation of embryonic day (E) 19 fetal type II cells with recombinant heparin-binding EGF-like growth factor (HB-EGF) or transforming growth factor (TGF)-alpha, but not with amphiregulin (AR), betacellulin (BTC) or epiregulin (EPR), increased fetal type II cell differentiation, as measured by surfactant protein B/C mRNA and protein levels. Next, we demonstrated that 5% cyclic stretch of E19 monolayers transfected with plasmid encoding alkaline phosphatase (AP)-tagged ligands shed mature HB-EGF and TGF-alpha into the supernatant and promoted type II cell differentiation. Release of these ligands was also observed in E19 cells subjected to higher degrees of cyclic strain, but not in cells exposed to continuous stretch. Interestingly, the addition of fibroblasts to type II cell cultures did not enhance release of HB-EGF. Whereas HB-EGF shedding was also detected in E18 cells exposed to 5% cyclic stretch, release of this ligand after 2.5% sustained stretch was restricted to cells isolated on E18 of gestation. In addition, mechanical stretch released EGF, AR and BTC. We conclude that mechanical stretch promotes fetal type II cell differentiation via ectodomain shedding of HB-EGF and TGF-alpha. The magnitude of shedding varied depending on gestational age, ligand, and strain protocol. These studies provide novel mechanistic information potentially relevant to fetal lung development and to mechanical ventilation-induced lung injury.
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Affiliation(s)
- Yulian Wang
- Department of Pediatrics, Women & Infants Hospital of Rhode Island and the Warren Alpert Medical School of Brown University, Providence, RI 02905, USA
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Hasan SU, Bharadwaj B, Remmers JE, Patel A, Rigaux A, Schneider J. Pulmonary feedback and gestational age-dependent regulation of fetal breathing movements. Can J Physiol Pharmacol 2008; 86:691-9. [PMID: 18841174 DOI: 10.1139/y08-078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Prenatal lung development requires fetal breathing movements (FBM). To investigate the dependence of FBM on feedback originating from the lung, we hypothesized that pneumonectomy stimulates FBM. Time-dated fetal sheep underwent bilateral pneumonectomy, unilateral pneumonectomy, or sham surgery at 125-130 days gestation. The incidence of FBM decreased in sham-operated fetuses at 142 days versus 130 days (p = 0.013), but was unchanged across all gestational ages in bilaterally pneumonectomized fetuses (p > or = 0.52). In unilaterally pneumonectomized fetuses, the incidence of FBM remained unchanged until 139 days and was higher than that of the bilaterally pneumonectomized fetuses at 130-136 days gestation (p < or = 0.03). The amplitude of integrated diaphragmatic electromyographic activity (integralEMG(di)) and total respiratory output (frequency of breathing x integralEMG(di)) were lower in pneumonectomized fetuses versus sham-operated fetuses at later gestational ages (p < 0.05). These decreases in integralEMG(di) and total respiratory output were most pronounced at 142 days in bilaterally pneumonectomized fetuses versus sham-operated fetuses (p = 0.006 and 0.016, respectively). Low-voltage electrocortical activity (ECoG) increased, and high-voltage ECoG decreased, in unilaterally pneumonectomized fetuses compared with sham-operated fetuses (p = 0.04). In conclusion, we provide new evidence that feedback from the fetal lung modulates the incidence and various components of phrenic nerve output, suggesting a positive feedback mechanism between FBM and lung development.
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Affiliation(s)
- Shabih U Hasan
- Departments of Pediatrics, Physiology and Surgery, Institute of Maternal and Child Health, Faculty of Medicine, Health Sciences Centre, 3330 Hospital Drive NW, University of Calgary, Calgary, AB T2N4N1, Canada.
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25
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te Pas AB, Davis PG, Hooper SB, Morley CJ. From liquid to air: breathing after birth. J Pediatr 2008; 152:607-11. [PMID: 18410760 DOI: 10.1016/j.jpeds.2007.10.041] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2007] [Revised: 09/19/2007] [Accepted: 10/24/2007] [Indexed: 11/30/2022]
Affiliation(s)
- Arjan B te Pas
- Division of Newborn Services, Royal Women's Hospital, Carlton, Victoria, Australia
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26
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Storme L, Rakza T, Houfflin-Debarge V, Dufour P, Bouissou A, Subtil D, Deruelle P. Physiopathologie des conséquences respiratoires néonatales de la rupture prématurée des membranes : application à la prise en charge néonatale. Arch Pediatr 2007; 14 Suppl 1:S42-8. [DOI: 10.1016/s0929-693x(07)80010-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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27
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Khan PA, Cloutier M, Piedboeuf B. Tracheal occlusion: A review of obstructing fetal lungs to make them grow and mature. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2007; 145C:125-38. [PMID: 17436297 DOI: 10.1002/ajmg.c.30127] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Fetal lung growth and functional differentiation are affected strongly by the extent that pulmonary tissue is distended (expanded) by liquid that naturally fills developing future airspaces. Methods that prevent normal egress of this lung fluid through the trachea magnify mechanical stretching of lung parenchymal cells, thereby promoting lung development. Indeed, experimental observations demonstrate that in utero tracheal occlusion (TO) performed on fetuses during the late canalicular-early saccular stage potently stimulates pulmonary growth and maturation. In this review, we present the four principle non-human animal models of TO/obstruction and discuss them in relation to their utility in elucidating lung development, in remedying congenital diaphragmatic hernia (CDH) as well as in investigating the stretching effects on growth and remodeling of the fine vasculature.
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Affiliation(s)
- Paul A Khan
- CRCHUL Medical Research Centre, Laval University, Québec, Canada
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