bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discrepant distribution of big endothelin (ET)-1 and ET receptors in the pulmonary artery
Authors: Takahashi H. , Soma S. , Muramatsu M. , Oka M. , Ienaga H. , Fukuchi Y. 
Published: October 2002

Since pulmonary vasculature is complex in terms of regional difference in structure and function, it is important to understand the site of endothelin (ET) synthesis and the distribution of the ET system along the axial pathways of pulmonary artery.The expression of big ET-1, ET converting enzyme (ECE) and ETAreceptors were examined in rat pulmonary arteries under normal and hypoxic conditions using an immunohistochemical method and Northern blot analysis.In normal conditions, big ET-1 was expressed in the intima and media of pulmonary arteries with a predominant distribution in the distal segments and a preferential localization in the media, while ETAreceptors were dominantly expressed in the proximal segments. ECE was constitutively expressed in the intima and media. Following exposure to hypoxia, messenger ribonucleic acid (mRNA) expression of ET-1 and ETAreceptors were up-regulated by two-fold and immunoreactivities for big ET-1, ECE, and ETAreceptors significantly increased by two to five-fold in the distal segments.Smooth muscle cells are an important source of endothelin-1 in the pulmonary artery. The distribution of big endothelin-1 and endothelin A receptors in pulmonary arteries was discrepant in normal conditions while their expression concomitantly increased in the distal segments in hypoxic conditions. This heterogeneity may play an important role in the regulation of pulmonary vascular tone.
Dose-response effect of oxygen on hyperinflation and exercise endurance in nonhypoxaemic COPD patients
Authors: Somfay A. , Porszasz J. , Lee S.M. , Casaburi R. 
Published: October 2002

Dynamic hyperinflation contributes to exertional breathlessness and reduced exercise tolerance in chronic obstructive pulmonary disease (COPD) patients. This study examined whether oxygen supplementation results in a dose-dependent decrease in hyperinflation associated with functional and symptomatic improvement.Ten severe COPD patients without clinically significant oxygen (O2) desaturation during exercise, and seven healthy subjects, performed five exercise tests at 75% of maximally tolerated work rate. Inspired oxygen fraction (FI,O2) was varied (0.21, 0.3, 0.5, 0.75 and 1.0) among tests in a randomized order. Ventilation (V'E) was measured, and end-inspiratory (EILV) and end-expiratory (EELV) lung volume changes were assessed from inspiratory capacity manoeuvres.In the patients, compared to room air, endurance time increased withFI,O2=0.3 (mean±sem 92±20%) and increased further withFI,O2=0.5 (157±30%). At isotime, compared to room air, there were significant reductions in dyspnoea score, EELV, EILV,V'Eand respiratory frequency (fR) withFI,O2=0.3. Improved endurance time negatively correlated with change in EELV (r=0.48, p=0.002) and EILV (r=043, p=0.005). The dyspnoea rating decrease correlated withfRdecrease. In healthy subjects, smallerV'EandfRdecreases were observed atFI,O2=0.5, accompanied by more modestly increased endurance.Oxygen supplementation during exercise induced dose-dependent improvement in endurance and symptom perception in nonhypoxaemic chronic obstructive pulmonary disease patients, which may be partly related to decreased hyperinflation and slower breathing pattern. This effect is maximized at an inspired oxygen fraction of 0.5.
Variations in the prevalence across countries of chronic bronchitis and smoking habits in young adults
Authors: Cerveri I. , Accordini S. , Verlato G. , Corsico A. , Zoia M.C. , Casali L. , Burney P. , de Marco R. 
Published: October 2002

The present work aims to assess the international variation in the prevalence of chronic bronchitis and its main risk factor, smoking habits, in young adults of 35 centres from 16 countries.Respiratory symptoms and pulmonary function were assessed in 17,966 subjects (20–44 yrs), randomly selected from the general population, in the frame of the European Community Respiratory Health Survey.The median prevalence of chronic bronchitis was 2.6%, with wide variations across countries (p<0.001; 0.7–9.7%). The prevalence of current smokers ranged 20.1–56.9% (p<0.001) with a median value of 40%. Current smoking was the major risk factor for chronic bronchitis, especially in males. Its effect increased according to number of pack-yrs: in males, the odds ratio of chronic bronchitis was 3.51 (95% confidence interval (CI) 2.31–5.32) in 1–14 pack-yrs smokers and increased to 17.32 (9.97–30.11) in ≥45 pack-yrs smokers with respect to nonsmokers. Only 30% of the geographical variability in prevalence could be explained by differences in smoking habits, suggesting that other environmental and/or genetic factors may play an important role.In conclusion, chronic bronchitis is a substantial health problem even in young adults. The impressive prevalence in current smokers in most countries highlights the need to improve the quality of prevention.
Ventilatory and cerebrovascular responses in normocapnic and hypercapnic COPD patients
Authors: Van de Ven M.J.T. , Colier W.N.J.M. , Van der Sluijs M.C. , Kersten B.T.P. , Oeseburg B. , Folgering H. 
Published: October 2002

This study investigated the hypothesis that hypercapnia in some chronic obstructive pulmonary disease (COPD) patients may be related to a high cerebrovascular response to carbon dioxide (CO2).The relationship between responses of ventilation and of cerebral blood volume (CBV) to acute changes in carbon dioxide tension in arterial blood (Pa,CO2) was measured in 17 chronic hypercapnic (Pa,CO2>6.0 kPa) and 16 normocapnic (Pa,CO2⪕6.0 kPa) COPD patients, who were matched for degree of airway obstruction (forced expiratory volume in one second 27% predicted). Results were compared with 15 age-matched healthy subjects. CBV was measered using near infrared spectroscopy during normo- and hypercapnia and related to inspired minute ventilation (V′I) and mouth occlusion pressure (P0.1). Hypercapnia (end-tidal pressure of carbon dioxide (ΔPET,CO2) >1 kPa) was induced by giving adequate amounts of CO2in the inspired air.During normocapnia, CBV (mL·100 g−1) was 2.41±0.66 and 2.90±0.60 (mean±sd) in the normocapnic and chronic hypercapnic patients, respectively, which was significantly lower compared to healthy subjects (3.53±0.77). All slopes of CO2responsiveness (ΔCBV/ΔPa,CO2, ΔV′I/ΔPa,CO2, ΔP0.1/ΔPa,CO2) were significantly lower in both COPD groups relative to healthy subjects, but were not significantly different between the COPD groups. A poor but positive correlation between ventilatory and cerebrovascular CO2responsiveness (ΔCBV/ΔPa,CO2and ΔV′I/ΔPa,CO2) was found in COPD patients and healthy subjects.The findings do not support the hypothesis of abnormal cerebrovascular responses to carbon dioxide in hypercapnic chronic obstructive pulmonary disease patients.
Comparison of the standard gamble, rating scale, AQLQ and SF-36 for measuring quality of life in asthma
Authors: Juniper E.F. , Norman G.R. , Cox F.M. , Roberts J.N. 
Published: October 2002

With interest in health economics growing, there is a demand for valid methods for measuring health-related quality of life (HRQL) in asthma using utilities. The aims of this study were to develop disease-specific versions of the standard gamble and rating scale, to compare their measurement properties with those of the Asthma Quality of Life Questionnaire (AQLQ) and the Medical Outcomes Survey Short-Form 36 (SF-36), as well as to determine their validity for assessing asthma-specific quality of life.Forty adults with symptomatic asthma participated in a 9-week observational study. Participants completed the standard gamble, rating scale, AQLQ, SF-36 and other measures of clinical asthma status at baseline and after 1, 5 and 9 weeks.In patients whose asthma was stable between assessments, reliability was good for the rating scale (intraclass correlation coefficient (ICC)=0.89) and the AQLQ (ICC=0.95) but more modest for the SF-36 mental score (ICC=0.68), SF-36 physical score (ICC= 0.65) and standard gamble (ICC=0.59). The responsiveness index was highest in the AQLQ (1.35), followed by the rating scale (0.74), the physical score of the SF-36 (0.61) and the standard gamble (0.31). Construct validity (correlation with other indices of health status) was strongest for the AQLQ and the rating scale.In conclusion, both the disease-specific rating scale and the Asthma Quality of Life Questionnaire have strong measurement properties for measuring asthma-specific quality of life; the Short-Form 36 health survey physical summary score has more modest properties. Although the disease-specific standard gamble has acceptable discriminative properties, its evaluative properties are too inadequate for it to be used in cost/utility analyses. Poor correlation between the standard gamble and the rating scale indicates that utilities cannot be derived from rating scale data.
Usefulness of transcutaneous Doppler jugular venous echo to predict pulmonary hypertension in COPD patients
Authors: Matsuyama W. , Ohkubo R. , Michizono K. , Abe M. , Nakamura Y. , Kawabata M. , Osame M. 
Published: October 2002

Pulmonary hypertension is an important factor that determines the prognosis of chronic obstructive pulmonary disease (COPD) patients. Echocardiography is a noninvasive and useful bedside method for measurement of pulmonary artery pressure. However, this method is sometimes difficult because of the overinflated lungs in COPD patients. This study attempted to estimate pulmonary hypertension in COPD patients using transcutaneous Doppler jugular vein flow velocity recording.The mean pulmonary artery pressure (MPAP) of 64 COPD patients was examined using cardiac catheterization. The right jugular vein flow velocity was measured within 24 h using transcutaneous Doppler echo, after which the ratio of diastolic flow (Df) and systemic flow (Sf) velocity was calculated. Subsequently, the statistical correlation of MPAP and the Df/Sf ratio was examined. MPAP was also measured using standard cardiac echo methods and the results were compared.The Df/Sf velocity ratio showed significant correlation with MPAP in COPD patients (r=0.844, p<0.0001). The sensitivity was 71.4%, and the specificity 95.3% (cut-off ratio=1.0). Jugular venous Doppler echo could be performed in all patients while other cardiac echo methods could not be performed in all patients. The specificity of the methods used was higher than other cardiac echo methods.Transcutaneous jugular vein flow velocity measurement may be applicable to bedside prediction of pulmonary hypertension in chronic obstructive pulmonary disease patients.
Effectiveness of salmeterolversusipratropium bromide on exertional dyspnoea in COPD
Authors: Ayers M.L. , Mejia R. , Ward J. , Lentine T. , Mahler D.A. 
Published: October 2002

The hypothesis of the study was that salmeterol and ipratropium would have similar dyspnoea ratings during steady-state cycle ergometry at 1 h, but that salmeterol would reduce dyspnoea at 6 h after administration in patients with chronic obstructive pulmonary disease (COPD).The study design was a randomized, double-blind trial in 16 patients (aged 63±11 yrs) with symptomatic COPD. Two days after familiarization with testing procedures, patients were randomly assigned to receive either two puffs (42 µg) of salmeterol and two puffs of placebo inhaler, or two puffs (36 µg) of ipratropium from each of two inhalers (total, 72 µg). Two days later, patients received the alternative medication. During exercise at 60% of peak oxygen consumption patients rated dyspnoea and performed inspiratory capacity manoeuvres each minute.Forced expiratory volume in one second was 1.13±0.48 L (37±13% predicted). Dyspnoea ratings were similar for salmeterol and ipratropium at 1 and 6 h. Inspiratory capacity was similar for salmeterol and ipratropium at 1 h, but significantly higher for salmeterol at 6 h (Δ=120 mL; p=0.03).It is concluded that with the doses used, salmeterol and ipratropium provided similar dyspnoea ratings during exercise at 1 and 6 h after administration.
How should airways resistance be measured in young children: mask or mouthpiece?
Authors: Child F. , Clayton S. , Davies S. , Fryer A.A. , Jones P.W. , Lenney W. 
Published: October 2002

The reproducibility and acceptability of airways resistance measurements using the interrupter technique (MicroRint) obtained using a mouthpiece were compared with those using a face mask.Fifty children aged 4–7 yrs performed four sets of sixRintmeasurements; two using a mouthpiece and two using a face mask with integral mouthpiece.Complete data were obtained from 45 (90%) children using the mouthpiece and 43 (86%) children using the mask. The two methods were equally repeatable with comparable intraclass correlation coefficients (ICC) and coefficients of variation. MeanRintvalues obtained using the mouthpiece were significantly lower than those using the face mask ((mean±sd) mouthpiece=0.81±0.18 kPa·L−1·s, mask=0.88±0.24 kPa·L−1·s p=0.0002). Although the mean paired differences between the two methods were small (0.07 kPa·L−1·s), the ICC and limits of agreement confirmed that the two methods could not be used interchangeably. Sixty-seven per cent of children preferred the face mask but this was more time-consuming (p=0.03). Children did not produce more repeatable results using their preferred method, nor did they improve with practice.Repeatable airway resistance measurements using the interrupter technique can be obtained from young children using either a mouthpiece or a face mask, but there are significant clinical and statistical differences between the results obtained.
High prevalence of asthma in five remote indigenous communities in Australia
Authors: Valery P.C. , Chang A.B. , Shibasaki S. , Gibson O. , Purdie D.M. , Shannon C. , Masters I.B. 
Published: October 2002

Data on the prevalence of asthma in children residing in remote indigenous communities in Australia are sparse, despite the many reports of high prevalence in nonindigenous children of this country. Two previous Australian studies have had poor participation rates, limiting interpretation of their results.A study of children in the Torres Strait and Northern Peninsula Area of Australia was conducted to document the prevalence of asthma symptoms. Five indigenous communities were randomly selected and trained interviewers, who were local indigenous health workers, recruited participants using a house-by-house approach. Information was collected by a structured face-to-face interview based on a standardized questionnaire constructed from the protocol International Study of Asthma and Allergy in Childhood; 1,650 children were included in the study with a 98% response rate.Overall, the prevalence of self-reported ever wheezing was 21%; 12% reported wheezing in the previous year; and 16% reported ever having asthma. There was significant variation in the prevalence of asthma symptoms between communities.It is concluded that there are significant intercommunity variations in the prevalence of asthma symptoms in remote communities and that the prevalence in these communities is as high as in nonindigenous groups.
EGTA treatment of human airwaysin vitrounmasks M1/MUC5AC mucin in submucosal glands
Authors: Roger P. , Gascard J-P. , Bara J. , Dulmet E. , Brink C. 
Published: October 2002

Mucin staining can be used to evaluate secretory activity of human airways. However, mucin epitopes may be masked by physicochemical properties of the secretions. The aim of this investigation was to examine the effects of the calcium chelator, ethyleneglycol-bis-(β-aminoethylether)-N, N, N′, N′-tetraacetic acid (EGTA) on the detection of M1/MUC5AC mucin in isolated human bronchial preparations.Immunohistochemical investigation and immunoradiometric assays with anti-M1 monoclonal antibodies (Mabs) were used to detect M1/MUC5AC mucin derived from bronchial preparations with an intact surface epithelium, or in tissues where the epithelium had been removed (rubbed preparations).The Mabs labelled both epithelial goblet cells and submucosal glandular cells in EGTA (4 mM)-exposed bronchial preparations, while only goblet cells were stained in EGTA (0.4 mM)-exposed tissues. The quantities of M1/MUC5AC mucin detected in either the bronchial fluids derived from EGTA (4 mM)-exposed intact and rubbed preparations or in bronchial fluids treated with EGTA (4 mM) were significantly increased by two-fold when compared with untreated control values (p<0.001). In addition, lactate dehydrogenase (LDH) activity and protein measurements were unaltered during exposure of human airways to EGTA (4 mM) suggesting that this treatment did not affect tissue viability.These results provide evidence that ethyleneglycol-bis-(β-aminoethylether)-N, N, N′, N′-tetraacetic acid (4 mM) facilitates the detection of M1/MUC5AC mucin by altering the physicochemical properties of respiratory mucin, thereby exposing epitopes with which anti-M1 monoclonal antibodies are reactive. This will allow more accurate measurement of secretory activity in human airwaysin vitro.
Small airways diseases: detection and insights with computed tomography
Authors: Hansell D.M. 
Published: October 2002

Diseases affecting the small airways are difficult to detect by traditional diagnostic tests. Widespread involvement is needed before symptoms and abnormalities on pulmonary function testing or chest radiography become apparent. Obstruction of the bronchioles may be detected indirectly by computed tomography (CT) because regional under-ventilation results in reduced perfusion which in turn is shown as a mosaic attenuation pattern of the lung parenchyma. When there is inflammation of the bronchioles with accompanying exudate, the airways may become directly visible on CT, for example in cases of diffuse panbronchiolitis.Quantification of the various morphological features of small airways disease is possible from CT images and this increased precision has aided investigations of structure/function relationships.An understanding of the pathology and microscopic distribution of disease in relation to the airways allows some prediction of the likely computed tomography appearances in this wide spectrum of conditions, and thus helps to refine the differential diagnosis.
Imaging of pneumonia: trends and algorithms
Authors: Franquet T. 
Published: October 2002

Pneumonia is one of the major infectious diseases responsible for significant morbidity and mortality throughout the world. Imaging plays a crucial role in the detection and management of patients with pneumonia.This review article discusses the different imaging methods used in the diagnosis and management of suspected pulmonary infections. The imaging examination should always begin with conventional radiography. When the results of routine radiography are inconclusive, computed tomography is mandatory. A combination of pattern recognition with knowledge of the clinical setting is the best approach to the pulmonary infectious processes.A specific pattern of involvement can suggest a likely diagnosis in many instances. In acquired immune deficiency syndrome patients, diffuse ground-glass and interstitial infiltrates are most commonly present inPneumocystis cariniipneumonia whereas in the nonimmunosuppressed patients, a segmental lobar infiltrate is suggestive of a bacterial pneumonia. Round pneumonia is most often encountered in children than adults and is most often caused byStreptococcus pneumoniae. Different combinations of parenchymal and pleural abnormalities may be suggestive for additional diagnoses.When an infectious pulmonary process is suspected, knowledge of the varied radiographic manifestations will narrow the differential diagnosis, helping to direct additional diagnostic measures, and serving as an ideal tool for follow-up examinations.
Noninvasive mechanical ventilation in acute hypoxaemic respiratory failure
Authors: Wysocki M. , Antonelli M. 
Published: October 2002

In acute hypoxaemic respiratory failure (HRF), oxygenation, reduction in the work of breathing and in dyspnoea may be achieved by delivering noninvasive mechanical ventilation (NIMV).Several uncontrolled and 13 randomized controlled studies (RCS) were reviewed. Uncontrolled studies confirmed the feasibility and the possibility to improve arterial blood oxygenation with NIMV. The 13 RCS compared NIMVversusa conventional approach in a total of 720 patients with HRF. Endotracheal intubation was required in 186 of the 358 patients (median (95% confidence interval (CI)) 51%, (40–63%)) assigned to a conventional approach and in 107 of the 362 patients (29% (20–39%)) assigned to NIMV. Eleven of the 13 RCS found a reduction in the rate of endotracheal intubation with NIMV with an absolute risk reduction of 31% (30–33%).Ten of the 13 RCS found a reduction in the mortality rate which was 30% (19–40%) in the control group and 19% (13–26%) in the NIMV group. The mean absolute risk reduction was 15% (10–20%).In conclusion, noninvasive ventilation appears to be a useful method in avoiding endotracheal intubation and probably in reducing the morbidity of patients with hypoxaemic respiratory failure.
The reproducibility and sample size requirements of exercise-induced bronchoconstriction measurements
Authors: Dahlén B. , O'Byrne P.M. , Watson R.M. , Roquet A. , Larsen F. , Inman M.D. 
Published: October 2002

Dry air exercise challenges are frequently used to screen medications that have potential utility in the management of exercise−induced bronchoconstriction (EIB). The purpose of this study was to determine the reproducibility of three outcome measurements made using such challenges, and sample size requirements for drug evaluation studies based on these outcomes.Forty adult subjects with asthma, who tested positively on a screening exercise challenge, were subjected to two further identical challenges, separated by 1 to >35 days. Outcome measurements included the maximum per cent fall in forced expiratory volume in one second (FEV1), after exercise (% fallmax), and the area under the per cent fall in FEV1/time curve for 30 min (AUC30) and 60 min (AUC60) after exercise.The reproducibility of these outcomes, as assessed by intraclass correlation coefficients was 0.72, 0.53 and 0.35 for % fallmax, AUC30and AUC60measurements, respectively. The sample size requirements to demonstrate an attenuation of EIB equivalent to a 50% reduction in % fallmaxwas 9, 14 and 19 subjects for the % fallmax, AUC30and AUC60responses, respectively (90% power).It is concluded that the maximum percentage fall in forced expiratory volume in one second has greater reproducibility and results in greater power in clinical trials than area under the curve measurements. Sample size calculation curves are provided which may be used in study design and interpretation of published studies.