Abstract:
:Recently, we reported that dyspnea on exertion is strongly associated with an increased oxygen cost of breathing in otherwise healthy obese women; the mechanism of dyspnea on exertion in obese men is unknown. Obese men underwent measurements of body composition, fat distribution, pulmonary function, steady state and maximal graded cycle ergometry, and oxygen cost of breathing. Nine men (34 ± 8 years, 35 ± 4 BMI) with ratings of perceived breathlessness of ≤2 during cycling, and ten men (36 ± 9 years, 38 ± 5 BMI) with ratings of perceived breathlessness ≥4 were studied (ratings of perceived breathlessness: 1.8 ± 0.4 vs. 4.7 ± 0.8, respectively; p<0.0001). Groups had only minor differences in fat distribution, pulmonary function, and steady state exercise. There was no association between ratings of perceived breathlessness and oxygen cost of breathing; but ratings of perceived breathlessness was strongly correlated with ratings of perceived exertion (RPE, rho=0.87, p<0.0001). The differences in exercise intensity, ventilatory demand, cardiovascular conditioning and/or the quality of respiratory sensation did not appear to play a role in the development of dyspnea on exertion. The mechanism of dyspnea on exertion in obese men seems unrelated to the oxygen cost of breathing.
journal_name
Respir Physiol Neurobioljournal_title
Respiratory physiology & neurobiologyauthors
Bernhardt V,Wood HE,Moran RB,Babb TGdoi
10.1016/j.resp.2012.10.007subject
Has Abstractpub_date
2013-01-15 00:00:00pages
241-8issue
2eissn
1569-9048issn
1878-1519pii
S1569-9048(12)00308-4journal_volume
185pub_type
杂志文章abstract:AIMS:Quantitatively measure and validate analysis of neural respiratory drive (NRD) using a commercial polysomnography system in children during sleep. METHOD:Surface electromyogram of the diaphragm (sEMGdi) recorded from primary snoring children were analysed. A subset was re-analysed to assess intra- and inter-inves...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2017.02.004
更新日期:2017-05-01 00:00:00
abstract::The vascular ATP-sensitive K+ (KATP) channel is a mediator of skeletal muscle microvascular oxygenation (PO2mv) during contractions in health. We tested the hypothesis that KATP channel function is preserved in chronic heart failure (CHF) and therefore its inhibition would reduce PO2mv and exacerbate the time taken to...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2017.01.009
更新日期:2017-04-01 00:00:00
abstract::A simple mathematical model of the carotid body chemoreceptor response is presented. The model assumes that the static chemoreceptor characteristic depends on oxygen saturation in the arterial blood and on CO2 arterial concentration. The values of O2 saturation and of CO2 concentration are computed, from pressure, usi...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/s0034-5687(01)00335-8
更新日期:2002-03-01 00:00:00
abstract::The neonatal rodent serves as useful and appropriate model within which to study respiratory system development. Despite an extensive literature that documents respiratory control in vitro, in vivo studies have relied upon whole body plethysmography to determine measures of respiratory frequency and tidal volume. Howe...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2014.07.018
更新日期:2014-10-01 00:00:00
abstract::We studied the differential responses of autonomic function in sea level residents (SLR), acclimatized lowlanders (ALH) in high altitude (HA) and HA natives (HAN) at >3500 m. Out of 771 male volunteers included in this cross-sectional study, SLR, ALH and HAN groups were comprised of 351, 307 and 113 volunteers, respec...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1016/j.resp.2018.04.002
更新日期:2018-08-01 00:00:00
abstract::The intrinsic positive-end-expiratory pressure (PEEPi) increases the inspiratory load, the cost of breathing and thus oxygen consumption (V(O2)). It has been shown that applying an extrinsic positive-end-expiratory pressure (PEEPe) reduces the inspiratory threshold load but the optimal PEEPe level is still in debate. ...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2004.10.001
更新日期:2005-04-15 00:00:00
abstract::Aquaporins (AQPs) are small, integral membrane proteins that facilitate water transport across cell membranes in response to osmotic gradients. Water transport across epithelia and endothelia in the peripheral lung and airways occurs during airway hydration, alveolar fluid transport and submucosal gland secretion. Sev...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章,评审
doi:10.1016/j.resp.2007.02.012
更新日期:2007-12-15 00:00:00
abstract::We hypothesized that progesterone may enhance the hypoxic ventilatory response and reduce the occurrence of apneas in newborn male rats. We studied 10-day-old rats chronically exposed to progesterone (Prog) or vehicle through the milk of lactating mothers. Respiratory and metabolic recordings were performed using whol...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2006.08.007
更新日期:2007-04-16 00:00:00
abstract::Respiratory responses to bronchoconstriction in asthma have been partially assessed and their significance is unclear. In 44 mild asthma patients we investigated respiratory responses during increasing levels of methacholine-induced bronchoconstriction. Inspiratory muscle activity, tidal volume, inspiratory and expira...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2013.08.013
更新日期:2013-12-01 00:00:00
abstract::Pulmonary surfactant fulfils diverse functions at the lung air-liquid interface of all air-breathing vertebrates. Neurohormonal regulation of surfactant synthesis and secretion is highly conserved among non-mammalian amniotes. Although the pattern of surfactant lipid maturation is similar among species, the onset and ...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章,评审
doi:10.1016/j.resp.2011.05.015
更新日期:2011-08-31 00:00:00
abstract::In chronic heart failure (HF), the alveolar-capillary membrane undergoes a remodeling process that negatively affects gas exchange. In case of alveolar-capillary gas diffusion impairment, arterial desaturation (SaO2) is rarely observed in HF patients. At play are 3 factors: overall pulmonary diffusing capacity (assess...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2016.06.004
更新日期:2016-11-01 00:00:00
abstract::Respiratory sinus arrhythmia (RSA) is the beat-to-beat fluctuation in heart rate at the frequency of the respiratory cycle. While it is common to study RSA under conditions of controlled breathing, where respiratory frequency, and sometimes tidal volume and inspiratory:expiratory ratio are controlled, the effect of co...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章,评审
doi:10.1016/j.resp.2010.04.021
更新日期:2010-11-30 00:00:00
abstract::Despite its necessity for understanding healthy brain aging, the influence of exercise intensity on cerebrovascular kinetics is currently unknown. We, therefore characterized middle cerebral artery blood flow velocity (MCAv) kinetics associated with two exercise intensities: low and moderate. We hypothesized that incr...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2019.01.013
更新日期:2019-04-01 00:00:00
abstract::Recent evidence suggests that surface electromyography of the parasternal intercostals (EMGpara) can be a non-invasive alternative to diaphragmatic EMG (EMGdi) for estimating neural respiratory drive (NRD) during cardiopulmonary exercise testing (CPET). The purpose of this study was to determine if non-respiratory mus...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2017.03.003
更新日期:2017-08-01 00:00:00
abstract::In day 15 chicken embryos, we determined the time course responses of acid-base balance and hematological respiratory variables during 24h exposure to 15, 20, 40 or 90% O(2), in the presence of 5% CO(2). Hypercapnic respiratory acidosis was initially (2h) only slightly (∼20%) compensated by metabolic alkalosis in norm...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2012.10.002
更新日期:2013-01-15 00:00:00
abstract::The aim of the study was to determine the feasibility of using a breath-holding test in assessing the sensitivity of the peripheral chemoreflex compared with the single-breath carbon dioxide test. The study involved 48 healthy volunteers between the ages of 18-29 years. The breath-holding test was performed followed b...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2016.10.005
更新日期:2017-01-01 00:00:00
abstract::The avian embryo toward end-incubation combines gas exchange through the chorioallantoic membrane (CAM) and pulmonary ventilation (V˙E). The main experiments examined breathing activity during cold-hypometabolism. Chicken embryos close to hatching were prepared for simultaneous measurements of oxygen consumption ( [Fo...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2017.03.004
更新日期:2017-08-01 00:00:00
abstract::Newborn rats chronically exposed to moderate hyperoxia (60% O2) exhibit abnormal respiratory control, including decreased eupneic ventilation. To further characterize this plasticity and explore its proximate mechanisms, rats were exposed to either 21% O2 (Control) or 60% O2 (Hyperoxia) from birth until studied at 3-1...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2014.03.010
更新日期:2014-07-01 00:00:00
abstract::We develop tidal-ventilation pulmonary gas-exchange equations that allow pulmonary shunt to have different values during expiration and inspiration, in accordance with lung collapse and recruitment during lung dysfunction (Am. J. Respir. Crit. Care Med. 158 (1998) 1636). Their solutions are tested against published an...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/s1569-9048(03)00066-1
更新日期:2003-06-12 00:00:00
abstract::Ischemia-reperfusion injury is the major complication of abdominal aortic surgery, and it mainly affects the lower extremities and remote organs. In the present study, the electrophysiological alterations in diaphragm that underlie the post-operative respiratory dysfunction were investigated. Wistar Albino rats were r...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2016.12.015
更新日期:2017-04-01 00:00:00
abstract::Bronchial responsiveness during methacholine (MCh) challenge was analysed in an elastase-induced mouse model of emphysema to explore the magnitude of the response in this model. Swiss mice were intratracheally instilled with saline or elastase (0.3 or 0.6 U). Twenty days afterward, mechanical ventilation data were col...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2014.01.009
更新日期:2014-04-01 00:00:00
abstract::Reduction in inspiratory capacity (IC) during exercise has been reported in chronic heart failure (CHF). Since inspiratory muscle dysfunction may be present to a variable degree, the assumption that IC reduction during exercise represents an increase in end-expiratory lung volume must be made with caution. This interp...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2018.04.005
更新日期:2018-08-01 00:00:00
abstract::Functional genomics is a systematic and high-throughput effort to analyze the functions of genes and gene products. Functional genomics is divided into gene- and phenotype-driven approaches. Gene-driven approaches to the functional genomics of sleep have demonstrated that transcripts of many genes change as a function...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章,评审
doi:10.1016/s1569-9048(03)00045-4
更新日期:2003-05-30 00:00:00
abstract::Rapid intravenous saline infusion, a model meant to replicate the initial changes leading to pulmonary interstitial edema, increases pulmonary arterial pressure in humans. We hypothesized that this would alter lung perfusion distribution. Six healthy subjects (29 ± 6 years) underwent magnetic resonance imaging to quan...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2011.12.013
更新日期:2012-03-15 00:00:00
abstract::Acetylcholine and ATP appear to mediate excitatory transmission between receptor (glomus) cells and the petrosal ganglion (PG) neuron terminals in the carotid body. In most species these putative transmitters are excitatory, while inhibitory effects had been reported in the rabbit. We studied the effects of the applic...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2010.05.003
更新日期:2010-07-31 00:00:00
abstract::Tibetans are the oldest population living permanently at high altitude. They possess several adaptations to low oxygen pressure that improve oxygen transport. We hypothesised that native Tibetans have mechanisms allowing them to maintain a better sleep structure and oxygenation during sleep at high altitude than newco...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/s1569-9048(03)00081-8
更新日期:2003-07-16 00:00:00
abstract::Peroxisome proliferator-activated receptor (PPAR)-β/δ is a transcription factor that belongs to the PPAR family, but the role of PPAR-β/δ in acute lung injury (ALI) induced by hyperbaric oxygen is unknown. In this study we investigated if PPAR-β/δ activation protects from hyperoxia-induced ALI in a rat model. ALI was ...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2014.04.004
更新日期:2014-08-01 00:00:00
abstract::Serotonin (5HT) is a powerful modulator of respiratory circuitry in vitro but its role in the development of breathing behavior in vivo is poorly understood. Here we show, using 5HT neuron-deficient Pet-1 (Pet-1(-/-)) neonates, that serotonergic function is required for the normal timing of postnatal respiratory matur...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2007.06.002
更新日期:2007-10-15 00:00:00
abstract::Increased transdiaphragmatic pressure, reduced muscle blood flow, and increased duty cycle have all been associated with a reduction in the center frequency (CFdi) of the diaphragm's electrical activity (EAdi). However, the specific influence of diaphragm activation on CFdi is unknown. We evaluated whether increased d...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2004.11.006
更新日期:2005-03-01 00:00:00
abstract::The prefrontal cortex is one of the key areas of the central mechanism of cardiovascular and respiratory control. Disinhibition of the prelimbic medial prefrontal cortex elicits tachypnoeic responses in anesthetized rats (Hassan et al., J. Physiol. 591: 6069-6088, 2013). The current study examines the effects of inhib...
journal_title:Respiratory physiology & neurobiology
pub_type: 杂志文章
doi:10.1016/j.resp.2014.07.009
更新日期:2014-12-01 00:00:00