Abstract:
:During exercise, children with congenital central hypoventilation syndrome (CCHS) demonstrate coupling of VE to exercise load, despite the absence of a VE response to changes in FICO2. To assess the effect of movement on VE, we studied six CCHS patients and six matched controls during passive motion in a motor-driven ergocycle at pedaling frequencies (PF) of 6 to 60 rpm. VE, VO2, VCO2, VT, heart rate, respiratory rate, SPO2, and PETCO2 were measured. During steady-state conditions, VE was constant at PF of 0 to 30 rpm, but increased at PF > or = 40 rpm in both controls and CCHS patients (p < 0.005). The increase in respiratory rate in CCHS patients was greater than in controls (p < 0.05) whereas VT increased similarly in both groups. At 60 rpm, VO2 increased in both groups, but VE/VO2 and VE/VCO2 increased in the CCHS patients and remained constant in the controls (P < 0.03; p < 0.04). From PF of 0 to 60, PETCO2 decreased from 47 +/- 7 to 41 +/- 6 mm Hg in the CCHS patients (p < 0.001) but remained unchanged in the controls (38 +/- 3 mm Hg; p = NS). An analysis of on-transient responses at 60 rpm revealed that VE increased immediately with the first breath after onset of motion in both groups, and that comparable differences in ventilatory patterns persisted in the two groups. We conclude that passive leg motion at PF > or = 40 increases VE in both CCHS patients and controls. In controls, VE was tightly coupled to VO2 and VCO2. However, in CCHS patients, passive leg motion elicited normalization of PETCO2.
journal_name
Am J Respir Crit Care Medauthors
Gozal D,Marcus CL,Ward SL,Keens TGdoi
10.1164/ajrccm.153.2.8564130subject
Has Abstractpub_date
1996-02-01 00:00:00pages
761-8issue
2eissn
1073-449Xissn
1535-4970journal_volume
153pub_type
杂志文章abstract::Relaxation was examined in diaphragm muscle strips of cardiomyopathic Syrian hamsters and control hamsters. Isotonic lengthening velocity and isometric tension decay were analyzed over the load continuum in response to twitch. For each load level (P), we measured the maximum extent of shortening (deltaL), the peak len...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.155.5.9154860
更新日期:1997-05-01 00:00:00
abstract::The inheritance of asthma, evident from its high family concordance, is not well understood. To investigate whether asthma may be inherited through a major gene with two alleles, segregation analyses were conducted in 3,369 individuals from 906 nuclear families enrolled, without selection, in a longitudinal study of r...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.154.1.8680670
更新日期:1996-07-01 00:00:00
abstract:RATIONALE:The molecular mechanisms underlying acute exacerbations of idiopathic pulmonary fibrosis (IPF) are poorly understood. We studied the global gene expression signature of acute exacerbations of IPF. OBJECTIVES:To understand the gene expression patterns of acute exacerbations of IPF. METHODS:RNA was extracted ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200810-1596OC
更新日期:2009-07-15 00:00:00
abstract::The aim of the study was to determine whether closing pressures or vascular distensibility can be used to describe liver venous hemodynamics when right atrial pressure is raised. The study was performed using a vascularly isolated pig liver preparation that allowed the independent control of portal vein and hepatic ar...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.152.2.7633700
更新日期:1995-08-01 00:00:00
abstract::Background: This document provides evidence-based clinical practice guidelines on the management of adult patients with community-acquired pneumonia.Methods: A multidisciplinary panel conducted pragmatic systematic reviews of the relevant research and applied Grading of Recommendations, Assessment, Development, and Ev...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,实务指引
doi:10.1164/rccm.201908-1581ST
更新日期:2019-10-01 00:00:00
abstract:RATIONALE:Serum chitinases may be novel biomarkers of airway inflammation and remodeling, but less is known about factors regulating their levels. OBJECTIVES:To examine serum chitotriosidase activity and YKL-40 levels in patients with asthma and chronic obstructive pulmonary disease (COPD) and evaluate clinically rele...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201504-0760OC
更新日期:2016-01-15 00:00:00
abstract::We addressed the hypothesis that noncholinergic parasympathetic nerves modulate airway smooth-muscle (ASM) tone in guinea pigs. The NO synthase inhibitor L-N(G)-nitro-arginine (L-NNA) and the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) potentiated cholinergic contractions and partly i...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.165.4.2004005
更新日期:2002-02-15 00:00:00
abstract::Elevated levels of ambient particulate matter (PM(10)) have been associated with increased cardiopulmonary morbidity and mortality. We previously showed that the deposition of particles in the lung induces a systemic inflammatory response that includes stimulation of the bone marrow. This marrow response is related to...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.164.5.2010160
更新日期:2001-09-01 00:00:00
abstract::Changes in dynamic lung compliance during inspiration and expiration cannot be modeled accurately with conventional algorithms. We developed a simple method to analyze pressure-volume (P/V) relationships under condition of nonlinearity (APVNL) and tested it in a lung model with known resistance and nonlinear P/V relat...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.158.4.9801011
更新日期:1998-10-01 00:00:00
abstract::Overproduction of NO by an inducible NO synthase (iNOS) plays a major role in the pathophysiology of septic shock, and selective inhibition of iNOS in this setting could be of great therapeutic value. In the present study, we evaluated the effects of L-canavanine, a selective iNOS inhibitor, in an animal model of sept...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.155.5.9154870
更新日期:1997-05-01 00:00:00
abstract::Chronic obstructive pulmonary disease (COPD) is a common and progressive disease that is influenced by both genetic and environmental factors. For many years, knowledge of the genetic basis of COPD was limited to Mendelian syndromes, such as alpha-1 antitrypsin deficiency and cutis laxa, caused by rare genetic variant...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
doi:10.1164/rccm.201808-1455SO
更新日期:2019-09-15 00:00:00
abstract::Although contraction of human isolated bronchi is mediated mainly by tachykinin NK2 receptors, NK1 receptors, via prostanoid release, contract small-size (approximately 1 mm in diameter) bronchi. Here, we have investigated the presence and biological responses of NK1 receptors in medium-size (2-5 mm in diameter) human...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.163.5.2002079
更新日期:2001-04-01 00:00:00
abstract::Airway hyperresponsiveness in asthma has been attributed to impaired ability of deep inspiration (DI) to stretch airway smooth muscle. We have retested this hypothesis by comparing the responses to methacholine of 10 asthmatic and 10 control subjects. After each dose subjects breathed tidally without deep inspiration ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.158.1.9707125
更新日期:1998-07-01 00:00:00
abstract::At the time of diagnosis, many sarcoidosis patients have no clinical indication for corticosteroid therapy, and prognostic parameters predicting deterioration are missing. In the present study, we investigated parameters derived from bronchoalveolar lavage (BAL) and serum in 77 patients with recently diagnosed sarcoid...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.156.5.97-02050
更新日期:1997-11-01 00:00:00
abstract::This study was designed to evaluate the value and applicability of tidal breathing pattern analysis to assess airflow obstruction in young children. The time needed to reach maximal tidal expiratory flow (TME) divided by total expiratory time (TE) was measured in 228 healthy children 3 to 11 yr of age, 64 patients wit...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.153.4.8616550
更新日期:1996-04-01 00:00:00
abstract::Although considerable evidence indicates a role for CD4(+) T lymphocytes (T cells) in airway inflammation, little data exist regarding the mechanisms underlying the induction and regulation of CD4(+) T cell reactivity to lung-specific antigens. To dissect the immunologic and molecular mechanisms of CD4(+) T cell dysre...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200404-464OC
更新日期:2004-12-01 00:00:00
abstract::The failure of patients to adhere to physician-prescribed regimens, either pharmacologic or behavioral, has been well documented in medical literature. Poor adherence to asthma medication regimens has been repeatedly demonstrated in both children and adults, with rates of nonadherence commonly reported from 30 to 70%....
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
doi:10.1164/ajrccm/149.2_Pt_2.S69
更新日期:1994-02-01 00:00:00
abstract::Smoking is the major risk factor for chronic respiratory symptoms, but dietary factors may also play a role. Most studies of diet and lung disease have been cross-sectional and conducted in populations with a Western-style diet. We analyzed the relation between dietary intake at baseline and new onset of cough with ph...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200306-789OC
更新日期:2004-08-01 00:00:00
abstract:RATIONALE:Sarcoidosis is known as a disease with high heterogeneity in clinical severity and inflammatory activity. On the basis of radiologic criteria, John Guyette Scadding developed a classification system, which is widely used, but is insufficient for clinical decision making. Therefore, biomarkers and genetic mark...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200705-742OC
更新日期:2008-02-01 00:00:00
abstract::Daily symptom, peak expiratory flow rate (PEFR), and medication diaries are often used in clinical trials of treatments for asthma on the assumption that they provide a better estimate of clinical status than does a questionnaire completed in the clinic. We conducted a study with the aim of comparing the measurement p...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.162.4.9912138
更新日期:2000-10-01 00:00:00
abstract::To examine the differential properties of mucous glycoproteins, we produced hypertrophic and metaplastic changes in goblet cells of rat nasal epithelium by intranasal instillation of ovalbumin (OVA) in OVA-sensitized rats, and by intranasal lipopolysaccharide (LPS) instillation. The epithelial mucosubstance was quanti...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.164.6.2012058
更新日期:2001-09-15 00:00:00
abstract::Because interleukin 8 (IL-8) is a potent neutrophil chemotactic and activating cytokine, we investigated IL-8 production in relation to neutrophil migration and elastase release in the human lung during unilateral community-acquired pneumonia (CAP). In 17 patients, the local response in the involved lung was compared ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.153.1.8542140
更新日期:1996-01-01 00:00:00
abstract::To elucidate the apparent contradictions in vascular remodeling in the lungs of patients with idiopathic pulmonary fibrosis, we evaluated alveolar vascularity in relation to the various degrees of fibrosis in surgically biopsied lungs of usual interstitial pneumonia. Alveolar capillary endothelial cells were intensely...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200308-1111OC
更新日期:2004-06-01 00:00:00
abstract::A 21-yr-old man with multiple pulmonary AV fistulae presented with moderate hypoxemia with chronic hyperventilation, which continued even after sufficient oxygenation by 100% O2 inhalation. The infusion of aminophylline, an adenosine receptor blocker, not only increased PaCO2 from 35 to 39 mm Hg but also depressed the...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
doi:10.1164/ajrccm.150.6.7952640
更新日期:1994-12-01 00:00:00
abstract::To determine the status of activation of lymphocytes and the role of cytokines on the inflammatory response of the bronchial mucosa in toluene diisocyanate (TDI) asthma, we performed a quantitative analysis of bronchial biopsies obtained from 15 subjects with TDI-induced asthma and seven normal control subjects. Marke...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.151.3.7533600
更新日期:1995-03-01 00:00:00
abstract::Secretory leukocyte protease inhibitor (SLPI) and elafin are structurally similar, low-molecular-weight antiproteases produced in the lung. We have developed a simple method for distinguishing the antiprotease activities of SLPI and elafin in lung lavage fluid from those of alpha 1-antitrypsin (alpha 1-AT) that is bas...
journal_title:American journal of respiratory and critical care medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1164/ajrccm.152.5.7582300
更新日期:1995-11-01 00:00:00
abstract::The low-affinity IgG Fc receptor, FcgammaRIIB, displays inhibitory potential in experimental models such as autoimmune diseases. However, whether this receptor is involved in the onset of allergic diseases remains unknown. This study examines the role of FcgammaRIIB in the initiation of allergic rhinitis in mice. Repe...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200302-239OC
更新日期:2004-01-01 00:00:00
abstract::We have undertaken this retrospective study to determine factors associated with in-hospital mortality and morbidity in 80 adult patients with severe Streptococcus pneumoniae meningitis. Clinical characteristics at admission of patients infected with susceptible (n = 54) and nonsusceptible (n = 17) strains to penicill...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.165.5.2105110
更新日期:2002-03-01 00:00:00
abstract:UNLABELLED:Although local tissue activation of the endothelin (ET) system contributes to the development of pulmonary hypertension, the impact of isolated chronic plasma hyperendothelinemia on the pulmonary circulation is unknown. METHODS:Mini-osmotic pumps were implanted in rats to deliver ET-1 during 7 or 28 days. A...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200403-340OC
更新日期:2005-03-01 00:00:00
abstract::Asthma is a common chronic disease without cure. Our understanding of asthma onset, pathobiology, classification, and management has evolved substantially over the past decade; however, significant asthma-related morbidity and excess healthcare use and costs persist. To address this important clinical condition, the N...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
doi:10.1164/rccm.201505-0963WS
更新日期:2015-12-01 00:00:00