Abstract:
:Most patients with cystic fibrosis (CF) are infected by Pseudomonas aeruginosa. Dextran exhibits anti-adhesive effects in preventing attachment of P. aeruginosa to epithelial cells (1). The initial purpose of this study was to evaluate the potential of dextran to alter the rheology and ciliary transportability of CF sputum prior to initiation of a clinical trial in patients with CF. Sputum samples were collected from 25 patients with CF not receiving rhDNase therapy for use in in vitro testing. Aliquots of CF sputum were treated with 10% vol. Ringer's or the same volume of Dextran 4000 to give a final concentration of 0.4% (4 mg/ml) or 4% (40 mg/ml) dextran in the sputum. Dog mucus samples were collected from seven healthy, anesthetized dogs from the endotracheal tube cuff. Aliquots of dog mucus were subjected to the same concentrations of dextran as the CF sputum. All treated samples were incubated for 30 min at 37 degrees C, and their rheologic properties (viscoelasticity) were evaluated by magnetic microrheometry. For 17 of the sputum samples, frog palate mucociliary transportability was determined from sputum movement on the ciliated, mucus-depleted frog palate, relative to native frog mucus control. Spinnability (cohesiveness) was evaluated by the filancemeter technique for eight sputum samples. Overall, whether for CF sputum or healthy dog mucus, Dextran 4000 treatment significantly reduced viscoelasticity and increased predicted mucociliary and cough clearability. Direct measurements of sputum mucociliary clearability on frog palate increased significantly with 0.4% dextran and 4% dextran compared with saline control. Sputum spinnability (cohesiveness) decreased significantly with both dextran concentrations, too. The effects on viscoelasticity and spinnability were greater at 4% than at 0.4%. There was a significant positive correlation between spinnability and viscoelasticity, and negative relationships between spinnability and both forms of clearability as predicted from viscoelastic measurements. This study suggests that treatment with Dextran 4000 can reduce the crosslink density and cohesiveness of CF and improve mucociliary and cough clearability. Dextran 4000 is an inexpensive and nontoxic agent that may be of benefit in patients with CF lung disease and perhaps in other respiratory disease where mucus retention is an important feature.
journal_name
Am J Respir Crit Care Medauthors
Feng W,Garrett H,Speert DP,King Mdoi
10.1164/ajrccm.157.3.9703059subject
Has Abstractpub_date
1998-03-01 00:00:00pages
710-4issue
3 Pt 1eissn
1073-449Xissn
1535-4970journal_volume
157pub_type
杂志文章abstract::Epidemiological data indicate that living or working in a moldy building is associated with increased risk of respiratory symptoms and disease related to inflammatory reactions, but biochemical evidence linking cause and effect is still scarce. The staff working in a mold-contaminated school, and a reference group wit...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.160.6.9903023
更新日期:1999-12-01 00:00:00
abstract:RATIONALE:Chronic hypoxia induces pulmonary vascular remodeling, pulmonary hypertension, and right ventricular hypertrophy. At present, little is known about mechanisms driving these responses. Hypoxia-inducible factor-1α (HIF-1α) is a master regulator of transcription in hypoxic cells, up-regulating genes involved in ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201302-0302OC
更新日期:2014-02-01 00:00:00
abstract::Theophylline is well-established in the management of asthma, and there is some evidence of an antiinflammatory effect in asthma. It is not known whether theophylline affects inflammatory markers such as sputum eosinophils and exhaled nitric oxide (NO) in patients with mild asthma not receiving inhaled steroid therapy...
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.164.2.2006043
更新日期:2001-07-15 00:00:00
abstract::Methodologies used to assess airway responsiveness (AR) in children administer the same dosage schedule to all children despite the great range in the size of subjects. The aim of this study was to examine the hypothesis that the level of AR is size dependent within same-age cohorts and between different ages. Among a...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.152.2.7633710
更新日期:1995-08-01 00:00:00
abstract::The involvement of platelet-activating factor (PAF) in bronchial hyperresponsiveness (BHR) in bronchial asthma has been controversial. To determine whether PAF is involved in BHR in humans, we carried out a randomized, double-blind, placebo-controlled, two-phase cross-over study on the effects of Y-24180, a potent, sp...
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.152.4.7551370
更新日期:1995-10-01 00:00:00
abstract::Idiopathic pulmonary fibrosis (IPF) is a progressive, life-threatening, interstitial lung disease of unknown etiology. The median survival of patients with IPF is only 2 to 3 years, yet some patients live much longer. Respiratory failure resulting from disease progression is the most frequent cause of death. To date w...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
doi:10.1164/rccm.201006-0894CI
更新日期:2011-02-15 00:00:00
abstract::We investigated whether exposure to ozone (O(3)) 24 hours after an allergen challenge test would increase airway eosinophilia induced by allergen in subjects with mild asthma with late airway response. Twelve subjects with mild atopic asthma participated in a randomized, single-blind study. Subjects underwent allergen...
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/rccm.2201013
更新日期:2002-10-15 00:00:00
abstract::Exhaled nitric oxide (eNO) is elevated in patients with inflammatory pulmonary diseases and it has attracted increasing interest as a simple, noninvasive marker of airway inflammation. Little is known, however, about factors that might affect eNO in healthy subjects. We measured eNO in 157 healthy 7- to 13-yr-old chil...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.159.1.9804134
更新日期:1999-01-01 00:00:00
abstract::Phl p5 is a major allergen of timothy grass and causes rhinitis and bronchial asthma in nearly all patients allergic to grass pollen. The biochemical processing of this molecule by the nasal mucosa at its first encounter and possible changes of its biologic activity are unknown. Two isoforms of the allergen were expre...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.157.4.9709040
更新日期:1998-04-01 00:00:00
abstract:RATIONALE:Interferon-gamma (IFN-gamma) is of central interest in the study of tuberculosis. A number of single-gene mutations have been identified in the IFN-gamma signaling pathway that predispose to severe mycobacterial disease, but the relevance of polymorphism within these genes to the common phenotype of tuberculo...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200601-088OC
更新日期:2006-08-01 00:00:00
abstract:RATIONALE:Roflumilast is a therapeutic agent in the treatment of chronic obstructive pulmonary disease (COPD). It has antiinflammatory effects; however, it is not known whether it can affect a biologic pathway implicated in COPD pathogenesis and progression. The self-propagating acetyl-proline-glycine-proline (AcPGP) p...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,随机对照试验
doi:10.1164/rccm.201503-0543OC
更新日期:2015-10-15 00:00:00
abstract::The cysteinyl leukotrienes (CysLTs) are important mediators of human asthma. Pharmacologic and clinical studies show that the CysLTs exert most of their bronchoconstrictive and proinflammatory effects through activation of a putative, 7-transmembrane domain, G-protein-coupled receptor, the CysLT1 receptor. The initial...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.163.1.2003101
更新日期:2001-01-01 00:00:00
abstract:RATIONALE:Little is known about the long-term outcomes and costs of survivors of acute respiratory distress syndrome (ARDS). OBJECTIVES:To describe functional and quality of life outcomes, health care use, and costs of survivors of ARDS 2 yr after intensive care unit (ICU) discharge. METHODS:We recruited a cohort of ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200505-693OC
更新日期:2006-09-01 00:00:00
abstract:RATIONALE:Drug-resistant tuberculosis transmission in hospitals threatens staff and patient health. Surgical face masks used by patients with tuberculosis (TB) are believed to reduce transmission but have not been rigorously tested. OBJECTIVES:We sought to quantify the efficacy of surgical face masks when worn by pati...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201107-1190OC
更新日期:2012-05-15 00:00:00
abstract::The purpose of this study was to describe the nature of diaphragm injury, to quantify the injury and number of macrophages at the light microscopic level, and to determine their association with airflow obstruction in humans. Partial-thickness diaphragm biopsies were obtained from 21 subjects going for thoracotomy sur...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.163.7.2001042
更新日期:2001-06-01 00:00:00
abstract::A growing body of evidence suggests that neutrophil-derived proteinases play a major role in lung tissue damage in cystic fibrosis (CF). Most previous studies have focused on serine proteinases such as neutrophil elastase, providing no information on the extent to which metalloproteinases participate in proteolytic pr...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.152.2.7633740
更新日期:1995-08-01 00:00:00
abstract:RATIONALE:Numerous studies have been published on the new Mycobacterium tuberculosis (MTB)-specific IFN-gamma release assays. However, their prognostic value for progression from latent tuberculosis infection (LTBI) to active TB has yet to be established. OBJECTIVES:To compare the QuantiFERON-TB Gold In-Tube assay (QF...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200711-1613OC
更新日期:2008-05-15 00:00:00
abstract::Because inflammation stimulates the expression of inducible nitric oxide (NO) synthase (iNOS) with an associated increased local NO production, we hypothesized that patients with pneumonia would have increased excretion of NO into their airways. To test this hypothesis, NO was measured in the exhaled air and from the ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.163.5.9906049
更新日期:2001-04-01 00:00:00
abstract:RATIONALE:End-tidal CO2 (EtCO2) is used to monitor cardiopulmonary resuscitation (CPR), but it can be affected by intrathoracic airway closure. Chest compressions induce oscillations in expired CO2, and this could reflect variable degrees of airway patency. OBJECTIVES:To understand the impact of airway closure during ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201806-1111OC
更新日期:2019-03-15 00:00:00
abstract::Great emphasis is placed on educating asthmatics to use action plans to achieve better control of symptoms. The use of peak flow meters (PFM) has been recommended as an important part of self-management plans. We studied 92 (47 F) adult patients with asthma in a primary care setting to compare the effectiveness of act...
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.157.2.9703060
更新日期:1998-02-01 00:00:00
abstract:RATIONALE:In cigarette smoking-induced chronic obstructive pulmonary disease, structural and functional derangements are characterized by parenchymal destruction and pulmonary hypertension. Statins are 3-hydroxy-3-methyl-glutaryl-coenzyme-A reductase inhibitors that have been used as lipid-lowering agents. These drugs ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200501-041OC
更新日期:2005-10-15 00:00:00
abstract::Guidelines, protocols, and checklists (together called "protocols") can be immensely helpful in the clinical arena. However, clinicians and health care systems relying on protocols must assess whether benefits are being accrued, whether such "benefits" are real, and whether harm can be detected. These concerns are imp...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201502-0314CP
更新日期:2016-01-01 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::The present prospective study was designed to determine the prevalence of pleural effusion at approximately 28 days after cardiac surgery and their subsequent course. This consecutive case study included 389 patients; 312 had only coronary artery bypass graft surgery (CABG) surgery, 37 had both valve and CABG surgery,...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200203-184OC
更新日期:2002-12-15 00:00:00
abstract::Colony-forming units of Mycobacterium tuberculosis in sputum were counted at 2-day intervals in 100 patients treated with 22 regimens of isoniazid, rifampin, pyrazinamide, ethambutol, or streptomycin, given alone or in combinations. The exponential fall in colony-forming units was measured by linear regression coeffic...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200210-1125OC
更新日期:2003-05-15 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::Long-term effects of high doses of inhaled corticosteroids (ICS) on bone density and metabolism are still uncertain. Fifty-one patients (37 male, 14 female) using beclomethasone or budesonide at a daily dose > 800 microgram/d (high-dose group [Group HD] mean: 983 microgram/d [prescribed dose x estimated compliance]) o...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.159.3.9802096
更新日期:1999-03-01 00:00:00
abstract:RATIONALE:Previous studies have demonstrated a high prevalence of sleep apnea (SA) in patients with chronic heart failure (HF), which is associated with higher rates of morbidity, mortality, and health care use. OBJECTIVES:To investigate the reported incidence, treatment, outcomes, and economic cost of SA in new-onset...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201003-0406OC
更新日期:2011-02-15 00:00:00
abstract::The mechanism responsible for diminished exercise performance in cystic fibrosis (CF) is not clear. We hypothesized that reduced muscle size, rather than an intrinsic muscle defect, was the primary factor in such diminished exercise performance. Twenty-two subjects with CF (14 females and eight males, aged 6.5 to 17.7...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.162.5.2003057
更新日期:2000-11-01 00:00:00
abstract::Collapsibility of the active pharynx, where active contraction of the upper airway muscles is evident, was previously reported to be higher in children with obstructive sleep apnea (OSA) than in those with primary snoring during sleep. Contribution of neuromuscular and anatomic factors to the increased collapsibility,...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.157.4.9702042
更新日期:1998-04-01 00:00:00