Daniel Piamonti , Luigi Panza , Roberto Flore , Valentina Baccolini , Daniela Pellegrino , Arianna Sanna , Altea Lecci , Giulia Lo Muzio , Dario Angelone , Flavio Marco Mirabelli , Matteo Morviducci , Paolo Onorati , Emanuele Messina , Valeria Panebianco , Carlo Catalano , Matteo Bonini , Paolo Palange
{"title":"Ventilatory efficiency in long-term dyspnoeic patients following COVID-19 pneumonia","authors":"Daniel Piamonti , Luigi Panza , Roberto Flore , Valentina Baccolini , Daniela Pellegrino , Arianna Sanna , Altea Lecci , Giulia Lo Muzio , Dario Angelone , Flavio Marco Mirabelli , Matteo Morviducci , Paolo Onorati , Emanuele Messina , Valeria Panebianco , Carlo Catalano , Matteo Bonini , Paolo Palange","doi":"10.1016/j.resp.2024.104285","DOIUrl":"10.1016/j.resp.2024.104285","url":null,"abstract":"<div><h3>Background</h3><p>Long COVID is defined as persistency of symptoms, such as exertional dyspnea, twelve weeks after recovery from SARS-CoV-2 infection.</p></div><div><h3>Objectives</h3><p>To investigate ventilatory efficiency by the use of cardiopulmonary exercise testing (CPET) in patients with exertional dyspnea despite normal basal spirometry after 18 (T<sub>18</sub>) and 36 months (T<sub>36</sub>) from COVID-19 pneumonia.</p></div><div><h3>Methods</h3><p>One hundred patients with moderate-critical COVID-19 were prospectively enrolled in our Long COVID program. Medical history, physical examination and lung high-resolution computed tomography (HRCT) were obtained at hospitalization (T<sub>0</sub>), 3 (T<sub>3</sub>) and 15 months (T<sub>15</sub>). All HRCTs were revised using a semi-quantitative CT severity score (CSS). Pulmonary function tests were obtained at T<sub>3</sub> and T<sub>15</sub>. CPET was performed in a subset of patients with residual dyspnea (mMRC ≥ 1), at T<sub>18</sub> and at T<sub>36</sub>.</p></div><div><h3>Results</h3><p>Remarkably, at CPET, ventilatory efficiency was reduced both at T<sub>18</sub> (V’<sub>E</sub>/V’CO<sub>2</sub> slope = 31.4±3.9 SD) and T<sub>36</sub> (V’<sub>E</sub>/V’CO<sub>2</sub> slope = 31.28±3.70 SD). Furthermore, we identified positive correlations between V’<sub>E</sub>/V’CO<sub>2</sub> slope at T<sub>18</sub> and T<sub>36</sub> and both percentage of involvement and CSS at HRCT at T<sub>0</sub>, T<sub>3</sub> and T<sub>15</sub>. Also, negative linear correlations were found between V’<sub>E</sub>/V’CO<sub>2</sub> slope at T<sub>18</sub> and T<sub>36</sub> and DL<sub>CO</sub> at T<sub>3</sub> and T<sub>15</sub>.</p></div><div><h3>Conclusions</h3><p>At eighteen months from COVID-19 pneumonia, 20 % of subjects still complains of exertional dyspnea. At CPET this may be explained by persistently reduced ventilatory efficiency, possibly related to the degree of lung parenchymal involvement in the acute phase of infection, likely reflecting a damage in the pulmonary circulation.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1569904824000788/pdfft?md5=dbf6465847a6d1c57f4e75bbaa5702a4&pid=1-s2.0-S1569904824000788-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141200645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ruzanna A. Shushanyan , Nikolay V. Avtandilyan , Anna V. Grigoryan , Anna F. Karapetyan
{"title":"The role of oxidative stress and neuroinflammatory mediators in the pathogenesis of high-altitude cerebral edema in rats","authors":"Ruzanna A. Shushanyan , Nikolay V. Avtandilyan , Anna V. Grigoryan , Anna F. Karapetyan","doi":"10.1016/j.resp.2024.104286","DOIUrl":"10.1016/j.resp.2024.104286","url":null,"abstract":"<div><p>High-altitude environments present extreme conditions characterized by low barometric pressure and oxygen deficiency, which can disrupt brain functioning and cause edema formation. The objective of the present study is to investigate several biomolecule expressions and their role in the development of High Altitude Cerebral Edema in a rat model. Specifically, the study focuses on analyzing the changes in total arginase, nitric oxide, and lipid peroxidation (MDA) levels in the brain following acute hypobaric hypoxic exposure (7620 m, SO<sub>2</sub>=8.1 %, for 24 h) along with the histopathological assessment. The histological examination revealed increased TNF-α activity, and an elevated number of mast cells in the brain, mainly in the hippocampus and cerebral cortex. The research findings demonstrated that acute hypobaric hypoxic causes increased levels of apoptotic cells, shrinkage, and swelling of neurons, accompanied by the formation of protein aggregation in the brain parenchyma. Additionally, the level of nitric oxide and MDA was found to have increased (p<0.0001), however, the level of arginase decreased indicating active lipid peroxidation and redox imbalance in the brain. This study provides insights into the pathogenesis of HACE by evaluating some biomolecules that play a pivotal role in the inflammatory response and the redox landscape in the brain. The findings could have significant implications for understanding the neuronal dysfunction and the pathological mechanisms underlying HACE development.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141200638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Koirala , A. Concas , A. Cincotti , Yi Sun , A. Hernández , M.L. Goodwin , L.B. Gladden , N. Lai
{"title":"Estimation of differential pathlength factor from NIRS measurement in skeletal muscle","authors":"B. Koirala , A. Concas , A. Cincotti , Yi Sun , A. Hernández , M.L. Goodwin , L.B. Gladden , N. Lai","doi":"10.1016/j.resp.2024.104283","DOIUrl":"10.1016/j.resp.2024.104283","url":null,"abstract":"<div><p>The utilization of continuous wave (CW) near-infrared spectroscopy (NIRS) device to measure non-invasively muscle oxygenation in healthy and disease states is limited by the uncertainties related to the differential path length factor (<span><math><mi>DPF</mi></math></span>). <span><math><mi>DPF</mi></math></span> value is required to quantify oxygenated and deoxygenated heme groups’ concentration changes from measurement of optical densities by NIRS. An integrated approach that combines animal and computational models of oxygen transport and utilization was used to estimate the <span><math><mi>DPF</mi></math></span> value <em>in situ</em>. The canine model of muscle oxidative metabolism allowed measurement of both venous oxygen content and tissue oxygenation by CW NIRS under different oxygen delivery conditions. The experimental data obtained from the animal model were integrated in a computational model of O<sub>2</sub> transport and utilization and combined with Beer-Lambert law to estimate <span><math><mi>DPF</mi></math></span> value in contracting skeletal muscle. A 2.1 value was found for <span><math><mi>DPF</mi></math></span> by fitting the mathematical model to the experimental data obtained in contracting muscle (T3) (Med.Sci.Sports.Exerc.48(10):2013–2020,2016). With the estimated value of <span><math><mi>DPF</mi></math></span>, model simulations well predicted the optical density measured by NIRS on the same animal model but with different blood flow, arterial oxygen contents and contraction rate (J.Appl.Physiol.108:1169–1176, 2010 and 112:9–19,2013) and demonstrated the robustness of the approach proposed in estimating <span><math><mi>DPF</mi></math></span> value. The approach used can overcome the semi-quantitative nature of the NIRS and estimate non-invasively <span><math><mi>DPF</mi></math></span> to obtain an accurate concentration change of oxygenated and deoxygenated hemo groups by CW NIRS measurements in contracting skeletal muscle under different oxygen delivery and contraction rate.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1569904824000764/pdfft?md5=98270b0a35e7743d357af86b35803e3e&pid=1-s2.0-S1569904824000764-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141093999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Angela L. Roger , Debolina D. Biswas , Meredith L. Huston , Davina Le , Aidan M. Bailey , Logan A. Pucci , Yihan Shi , Jacqueline Robinson-Hamm , Charles A. Gersbach , Mai K. ElMallah
{"title":"Respiratory characterization of a humanized Duchenne muscular dystrophy mouse model","authors":"Angela L. Roger , Debolina D. Biswas , Meredith L. Huston , Davina Le , Aidan M. Bailey , Logan A. Pucci , Yihan Shi , Jacqueline Robinson-Hamm , Charles A. Gersbach , Mai K. ElMallah","doi":"10.1016/j.resp.2024.104282","DOIUrl":"10.1016/j.resp.2024.104282","url":null,"abstract":"<div><p>Duchenne muscular dystrophy (DMD) is the most common X-linked disease. DMD is caused by a lack of dystrophin, a critical structural protein in striated muscle. Dystrophin deficiency leads to inflammation, fibrosis, and muscle atrophy. Boys with DMD have progressive muscle weakness within the diaphragm that results in respiratory failure in the 2nd or 3rd decade of life. The most common DMD mouse model – the <em>mdx</em> mouse – is not sufficient for evaluating genetic medicines that specifically target the human <em>DMD</em> (h<em>DMD</em>) gene sequence. Therefore, a novel transgenic mouse carrying the h<em>DMD</em> gene with an exon 52 deletion was created (h<em>DMD</em>Δ52;<em>mdx</em>). We characterized the respiratory function and pathology in this model using whole body plethysmography, histology, and immunohistochemistry. At 6-months-old, h<em>DMD</em>Δ52;<em>mdx</em> mice have reduced maximal respiration, neuromuscular junction pathology, and fibrosis throughout the diaphragm, which worsens at 12-months-old. In conclusion, the h<em>DMD</em>Δ52;<em>mdx</em> exhibits moderate respiratory pathology, and serves as a relevant animal model to study the impact of novel genetic therapies, including gene editing, on respiratory function.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141088329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gijnovefa Kola , Eriko Hamada , Rishi R. Dhingra , Frank J. Jacono , Thomas E. Dick , Denise Dewald , Kingman P. Strohl , Thomaz Fleury-Curado , Mathias Dutschmann
{"title":"Persistent glossopharyngeal nerve respiratory discharge patterns after ponto-medullary transection","authors":"Gijnovefa Kola , Eriko Hamada , Rishi R. Dhingra , Frank J. Jacono , Thomas E. Dick , Denise Dewald , Kingman P. Strohl , Thomaz Fleury-Curado , Mathias Dutschmann","doi":"10.1016/j.resp.2024.104281","DOIUrl":"10.1016/j.resp.2024.104281","url":null,"abstract":"<div><p>Shape and size of the nasopharyngeal airway is controlled by muscles innervated facial, glossopharyngeal, vagal, and hypoglossal cranial nerves. Contrary to brainstem networks that drive facial, vagal and hypoglossal nerve activities (FNA, VNA, HNA) the discharge patterns and origins of glossopharyngeal nerve activity (GPNA) remain poorly investigated. Here, an <em>in situ</em> perfused brainstem preparation (n=19) was used for recordings of GPNA in relation to phrenic (PNA), FNA, VNA and HNA. Brainstem transections were performed (n=10/19) to explore the role of pontomedullary synaptic interactions in generating GPNA. GPNA generally mirrors FNA and HNA discharge patterns and displays pre-inspiratory activity relative to the PNA, followed by robust inspiratory discharge in coincidence with PNA. Postinspiratory (early expiratory) discharge was, contrary to VNA, generally absent in FNA, GPNA or HNA. As described previously FNA and HNA discharge was virtually eliminated after pontomedullary transection while an apneustic inspiratory motor discharge was maintained in PNA, VNA and GPNA. After brainstem transection GPNA displayed an increased tonic activity starting during mid-expiration and thus developed prolonged pre-inspiratory activity compared to control. In conclusion respiratory GPNA reflects FNA and HNA which implies similar function in controlling upper airway patency during breathing. That GPNA preserved its pre-inspiratory/inspiratory discharge pattern in relation PNA after pontomedullary transection suggest that GPNA premotor circuits may have a different anatomical distribution compared HNA and FNA and thus may therefore hold a unique role in preserving airway patency.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140961633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
James Manifield, Charikleia Alexiou, Dimitrios Megaritis, Katherine Baker, Nicola Adams, Gill Barry, Ioannis Vogiatzis
{"title":"Effects of inspiratory muscle training on thoracoabdominal volume regulation in older adults: A randomised controlled trial","authors":"James Manifield, Charikleia Alexiou, Dimitrios Megaritis, Katherine Baker, Nicola Adams, Gill Barry, Ioannis Vogiatzis","doi":"10.1016/j.resp.2024.104278","DOIUrl":"10.1016/j.resp.2024.104278","url":null,"abstract":"<div><h3>Objectives</h3><p>We investigated the effect of inspiratory muscle training (IMT) on inspiratory muscle strength, functional capacity and respiratory muscle kinematics during exercise in healthy older adults.</p></div><div><h3>Methods</h3><p>24 adults were randomised into an IMT or SHAM-IMT group. Both groups performed 30 breaths, twice daily, for 8 weeks, at intensities of ∼50 % maximal inspiratory pressure (PImax; IMT) or <15 % PImax (SHAM-IMT). Measurements of PImax, breathing discomfort during a bout of IMT, six-minute walk distance, physical activity levels, and balance were assessed pre- and post-intervention. Respiratory muscle kinematics were assessed via optoelectronic plethysmography (OEP) during constant work rate cycling.</p></div><div><h3>Results</h3><p>PImax was significantly improved (by 20.0±11.9 cmH<sub>2</sub>O; p=0.001) in the IMT group only. Breathing discomfort ratings during IMT significantly decreased (from 3.5±0.9–1.7±0.8). Daily sedentary time was decreased (by 28.0±39.8 min; p=0.042), and reactive balance significantly improved (by 1.2±0.8; p<0.001) in the IMT group only. OEP measures showed a significantly greater contribution of the pulmonary and abdominal rib cage compartments to total tidal volume expansion post-IMT.</p></div><div><h3>Conclusions</h3><p>IMT significantly improves inspiratory muscle strength and breathing discomfort in this population. IMT induces greater rib cage expansion and diaphragm descent during exercise, thereby suggesting a less restrictive effect on thoracic expansion and increased diaphragmatic power generation.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1569904824000715/pdfft?md5=e1bf624e7ec93f6c825ab636f60e72a4&pid=1-s2.0-S1569904824000715-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140912622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"In silico investigation of inhalation condition impacts on hygroscopic growth and deposition of salbutamol sulphate in human airways","authors":"Sajad Eshaghi, Hassan Khaleghi, Reza Maddahian","doi":"10.1016/j.resp.2024.104271","DOIUrl":"10.1016/j.resp.2024.104271","url":null,"abstract":"<div><p>The objective of this study is to explore the transport, size growth, and deposition of Salbutamol Sulphate (SS) using Computational Fluid Dynamics (CFD). A CT-based realistic model of human airways from the oral cavity to the 5th generation of the lung was utilized as the computational domain. Four Test Cases (TC) with varying temperature and relative humidity (RH) under two inspiratory waveforms were considered to completely evaluate the impact of inhalation conditions on particle growth. Salbutamol Sulphate (SS) is a β2-adrenergic agonist and has been extensively used for asthma treatment. A monodispersed distribution of SS particles with an initial diameter of 167 nm was considered at the mouth inlet based on pharmaceutical data. Results indicated that inhalation of saturated/supersaturated air (RH>100%) leads to significant hygroscopic growth of SS particles with a factor of 10. In addition, the deposition efficiency of SS particles under the Quick and Deep (QD) inhalation profile was enhanced as the flow temperature and humidity increased. However, the implementation of Slow and Deep (SD) inspiratory waveform revealed that the same particle size growth is achieved in the respiratory system with lower deposition efficiency in the mouth-throat (less than 3%) and tracheobronchial airway (less than 2.18%). For the escaped particles form the right lung, in the SD waveform under TC 3, the maximum particle size distribution was for 600 nm particles with 25% probability. In the left lung, 30% of the particles were increased up to 950 nm in size. For the QD waveform in TC 3 and TC4, the most frequent particles were 800 nm with 36% probability. This holds practical significance in the context of deep lung delivery for asthmatic patients with enhanced deposition efficiency and large particle size. The findings of the present study can contribute to the development of targeted drug delivery strategies for the treatment of pulmonary diseases using hygroscopic dry powder formulations.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140850304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Renato Filogonio , Luciane H. Gargaglioni , Joseph Santin
{"title":"Evaluation of sex-based differences in central control of breathing in American bullfrogs","authors":"Renato Filogonio , Luciane H. Gargaglioni , Joseph Santin","doi":"10.1016/j.resp.2024.104269","DOIUrl":"10.1016/j.resp.2024.104269","url":null,"abstract":"<div><p>The neural control of breathing exhibits sex differences. There is now a large effort to account for biological sex in mammalian research, but the degree to which ectothermic vertebrates exhibit sex differences in the central control of breathing is not well-established. Therefore, we compared respiratory-related neural activity in brainstem-spinal cord preparations from female and male bullfrogs to determine if important aspects of the central control of breathing vary with sex. We found that the breathing pattern was similar across males and females, but baseline frequency of the respiratory network was faster in females. The magnitude of the central response to hypercapnia was similar across sexes, but the time to reach maximum burst rate occurred more slowly in females. These results suggest that sex differences may account for variation in traits associated with the control of breathing and that future work should carefully account for sex of the animal in analysis.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140863516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carlos Eduardo Santos , Luis Felipe da Fonseca Reis , Sidney Fernandes da Silva , Iasmim Maria Pereira Pinto Fonseca , Wellington de Oliveira Pereira , Laura Franco Pessoa , Paolo Blanco Villela , Agnaldo José Lopes
{"title":"Dynamic hyperinflation on exercise and its relationship with lung mechanics at rest in adults with central obesity","authors":"Carlos Eduardo Santos , Luis Felipe da Fonseca Reis , Sidney Fernandes da Silva , Iasmim Maria Pereira Pinto Fonseca , Wellington de Oliveira Pereira , Laura Franco Pessoa , Paolo Blanco Villela , Agnaldo José Lopes","doi":"10.1016/j.resp.2024.104270","DOIUrl":"https://doi.org/10.1016/j.resp.2024.104270","url":null,"abstract":"<div><p>This study aimed to evaluate the presence of dynamic hyperinflation (DH) during the Glittre-ADL test (TGlittre) coupled to the dynamic ventilation measurements in people with central obesity (pwCO) and to correlate it with lung mechanics at rest. Sixty-four pwCO underwent TGlittre and the following resting lung function tests: spirometry and impulse oscillometry system (IOS). On TGlittre, 22 participants presented DH at the end of the test (DH group), while 42 did not present DH (NDH group). Body mass index (BMI), waist circumference (WC), and hip circumference (HC) were higher in the DH group than in the NDH group. IOS abnormalities were more common in the DH group compared to the NDH group. TGlittre time significantly correlated with BMI, WC, waist-to-hip ratio (WHR), and neck circumference (NC). Delta inspiratory capacity correlated significantly with WC, HC, NC, and resonance frequency measured by IOS. Thus, pwCO perform worse on TGlittre, and DH is frequent in those with higher anthropometric indices and worse lung mechanics.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140816624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Obesity-related reduced spirometry and altered breathing pattern are associated with mechanical disadvantage of the diaphragm","authors":"Leonardo Cesanelli , Federico Cesanelli , Hans Degens , Danguole Satkunskiene","doi":"10.1016/j.resp.2024.104267","DOIUrl":"https://doi.org/10.1016/j.resp.2024.104267","url":null,"abstract":"<div><p>The aim of this study was to characterize the breathing patterns of individuals with obesity during routine activities such as sitting and standing, and to identify potential contributors to alterations in these patterns. Measurements performed in 20 male subjects with obesity (BMI, 31.8±1.5 kg/m<sup>2</sup>) and 20 controls (BMI, 23.5±1.4 kg/m<sup>2</sup>) included anthropometric parameters, breathing-patterns in sitting and standing positions, spirometry, maximal respiratory pressures, and diaphragm B-mode ultrasonography. Individuals with obesity exhibited lower tidal volume and increased respiratory rate to maintain a similar minute-ventilation (p<0.05). Subjects with obesity demonstrated impaired spirometry and respiratory muscle strength, with inspiratory functions being notably compromised (p<0.05). Individuals with obesity had a greater diaphragm thickness at end inspiration but lower thickening-fraction at end quiet and forced breathings and reduced diaphragmatic displacement and excursion during maximal breaths (p<0.05). BMI was negatively associated with all respiratory function markers (p<0.05). Individuals with obesity exhibit a higher respiratory rate but lower tidal volume, likely to accommodate decreased compliance and excess thoracic and abdominal fat, further hindering inspiratory function. Moreover, increased adiposity is associated with a thicker but weaker diaphragm, primarily due to the diaphragm's mechanical disadvantage rather than its intrinsic inability to generate force.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140816578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}