bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnosis of nosocomial pneumonia in medical ward: repeatability of the protected specimen brush
Authors: Herer B. , Fuhrman C. , Demontrond D. , Gazevic Z. , Housset B. , Chouaïd C.
Published: October 2002

The aims of this study were to assess the repeatability of two pairs of protected specimen brushes (PSB) done successively in the same lung area and either processed at the bedside or in the laboratory, and to provide a description of the bacteriological findings in 39 cases of suspected nosocomial pneumonia occurring in nonventilated patients.

Four PSB were divided into two pairs. One pair of brushes (Pb) was prepared at bedside and then sent to the laboratory; the other pair (Pl) was immediately sent to the laboratory for complete processing.

According to a 103 colony forming units (cfu)·mL−1threshold, 49% out of 156 PSB were positive. Using the 103 cfu·mL threshold, the Pl brushes were 89.7% concordant while the Pb brushes were 76.9% concordant. The repeatability as expressed by Κ-value of the cultures of PSB was higher for Pl brushes than for Pb brushes (Κ-values of 0.795 and 0.537 respectively, p=0.12). Bacterial species were isolated in 58.3% of 156 PSB (176 isolates). In 14 cases, cultures of PSB disclosed more than one micro-organism in a concentration >103 cfu·mL−1. The most frequently isolated organisms werePseudomonasspp. (23.9%), Enterobacteriaceae (23.3%),Streptococcusspp. (21.6%) andStaphylococcusspp. (13.1%). Polymicrobial cultures were more frequent if the patient had a tracheostomy (seven out of the nine patients with a tracheostomyversusseven out of the 30 patients without a tracheostomy, p<0.01). Bacteriological discrepancies leading to a potential troublesome choice in antibiotherapy were observed in 31.8% of the patients for Pl brushes and 56.5% of the patients for Pb brushes.

There is a low degree of repeatability of protected specimen brushes outside intensive care units which seem dependent on sampling processing. The distribution of pathogens found in case of suspicion of nosocomial pneumonia in nonventilated patients appears to be similar to that obtained in ventilator-associated pneumonia.
Total energy expenditure in children with obstructive sleep apnoea syndrome
Authors: Bland R.M. , Bulgarelli S. , Ventham J.C. , Jackson D. , Reilly J.J. , Paton J.Y.
Published: October 2002

Childhood obstructive sleep apnoea syndrome (OSAS) acts as a check on growth and nutritional status. An increase in sleeping energy expenditure has been proposed as a possible mechanism, but to date, no studies have determined whether energy requirements (total energy expenditure; TEE) are raised in OSAS. The aim of this study was to test the hypothesis that OSAS is associated with increased TEE.

Eleven children (mean±sd 5.8±2.2 yrs of age) with OSAS confirmed by nocturnal polysomnography were each matched with a pair of healthy controls (n=22) of the same age and sex. TEE was measured using the doubly-labelled water method in all subjects. In 10/11 patients TEE was also measured after adenotonsillectomy and changes in TEE assessed.

There was no significant difference in TEE between patients (mean±sd 325±44 kJ·kg−1·day−1) and controls (339±48 kJ·kg−1·day−1), nor between patients and age- and sex-specific literature data on TEE, using the doubly-labelled water method. Differences in TEE within patients, beforeversusafter surgery, were minor and not statistically significant.

This study does not support the hypothesis that obstructive sleep apnoea syndrome in childhood is associated with increased energy requirements, and suggests that alternative explanations for the effect of this syndrome on growth and energy balance should be sought.
Prospective population-based study on the survival of patients with lung cancer
Authors: Mäkitaro R. , Pääkko P. , Huhti E. , Bloigu R. , Kinnula V.L.
Published: October 2002

The purpose of this study was to evaluate the change, over 20 yrs, in the survival of lung cancer patients in a population-based study.

Information on all patients with lung cancer in a defined geographical area during 1990–1992 (n=602) was prospectively gathered. The survival of these patients was assessed and also compared with the results of a similar study in the same area during the years 1968–1971 (n=446).

The 5-yr survival had improved during 20 yrs from 4% to 12%. The 5-yr survival of the patients with squamous cell carcinoma had increased from 6% to 16%, and adenocarcinoma from 4% to 19%, whereas the survival of small cell carcinoma had remained the same (2% and 3%, respectively). Even though the recent patients were older than those of the earlier series the proportion of surgically treated patients had remained the same (16% and 20%), but the 5-yr survival of patients who had been operated on had increased significantly from 23% to 48%. The differences in survival in the second cohort (1990–1992) between histological types (Chi-squared logrank=59.2), tumour, node, metastasis stages (Chi-squared logrank=199.6), symptomatic stages (Chi-squared logrank=120, p<0.001) and treatment (Chi-squared logrank=277) were significant.

Based on this study the independent prognostic factors for better survival of lung cancer patients are tumour, node, metastasis stages I and II, surgical treatment and Feinstein's symptomatic stages I and II.
The effects of respiratory infections, atopy, and breastfeeding on childhood asthma
Authors: Oddy W.H. , de Klerk N.H. , Sly P.D. , Holt P.G.
Published: October 2002

The objectives of the present study were to quantify the association of atopy and respiratory infections with asthma, and exclusive breastfeeding with respiratory illness, atopy and asthma in children.

A cohort study of 2,602 children enrolled prior to birth and followed prospectively, provided data on respiratory illness, the method of feeding in the first year of life, as reported on a prospective diary card, and current asthma at the age of 6 yrs (defined as doctor-diagnosed asthma with wheeze in the last year or cough without a cold, and currently taking either preventer or reliever asthma medication), as reported by parental questionnaire. Atopy was defined by a positive skin-prick test assessed at the age of 6 yrs.

Wheezing lower respiratory illness (LRI) in the first year of life, particularly multiple episodes of wheezing LRI, increased the risk for current asthma in both nonatopic (odds ratio (OR) 4.10, p⪕0.0005) and atopic children (OR 9.00, p⪕0.0005), but did not increase the risk for atopy. In contrast, up to three upper respiratory tract infections demonstrated a negative association and four or more a positive risk for current asthma in unadjusted (p=0.006) and adjusted (p=0.057) analysis. Following adjustment, exclusive breastfeeding for <4 months was associated with an increased risk for current asthma (OR 1.36, 95% confidence interval 1.00–1.85, p=0.047).

Wheezing lower respiratory illness in the first year of life and atopy are independently associated with increased risk for current asthma at the age of 6 yrs, suggesting that their effects are mediatedviadifferent causal pathways and that these risk factors are multiplicative when they operate concomitantly within individual children. Exclusive breastfeeding protects against asthmaviaeffects on both these pathways, as well as through other as yet undefined mechanisms.
Lung function of school children with low levels of α1-antitrypsin and tobacco smoke exposure
Authors: von Ehrenstein O.S. , von Mutius E. , Maier E. , Hirsch T. , Carr D. , Schaal W. , Roscher A.A. , Olgemöller B. , Nicolai T. , Weiland S.K.
Published: October 2002

Exposure to environmental tobacco smoke (ETS) and other air pollutants has been associated with small decrements in lung function. The susceptibility to pollution exposure may, however, vary substantially between individuals. Children with an impaired protease-antiprotease balance may be particularly vulnerable. Therefore this study aimed to investigate the effects of ETS exposure on children with reduced levels of α1-antitrypsin (α1-AT).

Random samples of school children (aged 9–11 yrs) (n=3,526) were studied according to the International Study of Asthma and Allergies in Childhood (ISAAC) phase II protocol, including parental questionnaires, pulmonary function and allergy testing. Blood samples were obtained to measure plasma levels of α1-AT and to genotype for pleomorphic protein inhibitor (Pi)Z and PiS alleles.

Children with low levels of α1-AT (≤116 mg·dL−1) showed significant, albeit small decrements in baseline lung function. When exposed to ETS, pronounced decrements of pulmonary function, particularly in measures of mid- to end-expiratory flow rates, were seen in these children as compared to exposed children with normal levels of α1-AT. The mean levels of % predicted±se in both groups were: maximum expiratory flow at 50% of vital capacity 79.4±7.2versus99.0±1.5, maximum expiratory flow at 25% of vital capacity 67.4±10.0versus100.3±2.1, maximal midexpiratory flow 73.7±8.6versus99.9±1.7.

These findings suggest that school children with low levels of α1-antitrypsin are at risk of developing pronounced decrements in pulmonary function, particularly if they are exposed to environmental tobacco smoke. Parents of children with heterozygous α1-antitrypsin deficiency resulting in significantly reduced blood concentrations should be advised to prevent their children from being exposed to environmental tobacco smoke and dissuade them from taking up smoking.
Intracellular glutathione and bronchoalveolar cells in fibrosing alveolitis: effects ofN-acetylcysteine
Authors: Behr J. , Degenkolb B. , Krombach F. , Vogelmeier C.
Published: October 2002

Extracellular glutathione deficiency and exaggerated oxidative stress may contribute to the pathogenesis of fibrosing alveolitis (FA). High-doseN-acetylcysteine (NAC) supplementation partially reverses extracellular glutathione depletion and oxidative damage, but effects on intracellular glutathione are unknown.

Intracellular total glutathione (GSHt) and activation of bronchoalveolar lavage cells (BAC) obtained from 18 FA patients (9 males, aged 52±2 yrs), before and after 12 weeks of oral NAC (600 mgt.i.d.), were assessed. Eight healthy nonsmokers (2 males, aged 36±6 yrs) served as a control group.

Intracellular GSHtwas decreased in FA (1.57±0.20 nmol·1×106BAC−1versus2.78±0.43 nmol·106BAC−1). After NAC treatment, the intracellular GSHtcontent increased (1.57±0.20versus1.87±0.19 nmol·1×106BAC−1). The spontaneous oxidative activity of BAC decreased after NAC treatment (2.7±0.8versus1.0±0.2 nmol·1×106BAC−1·h−1). Interleukin-8 concentration (82.1±31.5versus80.0±22.6 pg·mL bronchoalveolar fluid (BALF), nonsignificant (ns)) and myeloperoxidase activity (1.93±0.64versus1.55±0.47 mU·mL−1BALF, ns) did not change significantly, but were found to be inversely correlated to intracellular GSHt.

In conclusion, high-doseN-acetylcysteine supplementation increases intracellular glutathione levels slightly. This increase is associated with a mild reduction of oxidative activity but not with a reduction of bronchoalveolar cell activation in these patients.
Expiratory flow limitation during exercise in COPD: detection by manual compression of the abdominal wall
Authors: Abdel Kafi S. , Sersté T. , Leduc D. , Sergysels R. , Ninane V.
Published: October 2002

Manual compression of the abdomen (MCA) during spontaneous expiration is a simple method for the detection of flow limitation in the chronic obstructive pulmonary disease (COPD) patients during resting breathing, based on comparison of flow/volume curves obtained during MCA with that of the preceding control breath. It was assessed whether this nonstandardized technique is also feasible during exercise.

MCA was performed during resting breathing and constant-exercise work at one- and two-thirds maximal mechanical power output (W′max) in six normal subjects and 12 COPD patients. Changes in end-expiratory lung volume (EELV) were also studied.

With the aid of inspection, abdominal palpation and lung auscultation, MCA could always be applied during expiration. Flow limitation was never detected in the six normal subjects, whereas four of the COPD patients were flow limited at rest, seven during exercise at one-thirdW′maxand nine during exercise at two-thirdsW′max. Expiratory flow limitation detected by MCA was always associated with an increase in EELV during exercise, indicating dynamic hyperinflation occurrence or increase.

It is concluded that manual compression of the abdomen is a very simple and reliable method for the detection of flow limitation during exercise.
Acute protection against exercise-induced bronchoconstriction by formoterol, salmeterol and terbutaline
Authors: Richter K. , Janicki S. , Jörres R.A. , Magnussen H.
Published: October 2002

The onset of bronchoprotection as obtained by various β2-agonists has not been examined in a comparitive study. In this study, the onset of bronchodilation and protection against exercise-induced bronchoconstriction in asthmatics after inhalation of the long-acting β2-agonists formoterol and salmeterol and the short-acting β2-agonist terbutaline were measured.

Twenty-five subjects with asthma and a history of exercise-induced bronchoconstriction (mean baseline forced expiratory volume in one second (FEV1): 90% predicted; mean fall in FEV1after exercise: 31% from baseline) were enrolled in this double-blind, double-dummy, placebo-controlled, randomized, four-period crossover study. Exercise challenges were performed on 12 days at either 5, 30, or 60 min after inhalation of a single dose of formoterol (12 µg Turbuhaler®), salmeterol (50 µg Diskus®), terbutaline (500 µg Turbuhaler®) or placebo.

Exercise-induced bronchoconstriction (maximum fall in FEV1or area under the curve) did not differ significantly between terbutaline, formorerol and salmeterol either 5, 30, or 60 min after inhalation of the study medication. In contrast, the onset of bronchodilation was slower after salmeterol compared to terbutaline and formoterol (p<0.05, each), which both showed a similar time course. At all time points between 5 and 60 min, formoterol provided significantly greater bronchodilation than salmeterol (p<0.05).

These data indicate that equipotent doses of the bronchodilators salmeterol, formoterol and terbutaline were similarly effective with respect to their short-term protective potency against exercise-induced bronchoconstriction, despite the fact that the time course of bronchodilation was significantly different between the three β2-agonists.
Colistin stimulates the activity of neutrophil elastase andPseudomonas aeruginosaelastase
Authors: Jones A. , Elphick H. , Pettitt E. , Everard M.L. , Evans G.S.
Published: October 2002

Nonantimicrobial effects of antibiotics may contribute to their activity in the treatment of infective airway disease. The aim of this study was to identify antibiotics used for the treatment of infection in cystic fibrosis that may alter the activity of human neutrophil elastase (HNE) andPseudomonas aeruginosaelastase (PE).

The effect of antibiotics on the activity of purified HNE and PE, and HNE in sputum was assessed using colourimetric and fluorescent substrate assays by kinetic measurements, and by examining the interaction of HNE with inhibitors.

Ceftazidime, tobramycin, and gentamycin slightly inhibited purified HNE activity whereas erythromycin and colistin significantly stimulated purified HNE and PE (395 and 557%, respectively). However, only colistin increased HNE activity in sputum (+102%) and was therefore studied in more detail. This increase in activity was not due an interference with the specific inhibition of HNE by α1-antitrypsin but colistin was found to reverse the inhibitory effects of small molecular weight molecules like heparin.

Colistin increases the activity of human neutrophil elastase andPseudomonas aeruginosaelastase, two proteases that contribute to the pathogenesis of cystic fibrosis airway disease.
Risk of chemotherapy-induced pulmonary fibrosis is associated with polymorphic tumour necrosis factor-a2 gene
Authors: Libura J. , Bettens F. , Radkowski A. , Tiercy J.M. , Piguet P.F.
Published: October 2002

In some patients, chemotherapy (CHT) of cancer can result in pulmonary inflammation and fibrosis, eventually leading to respiratory insufficiency.

As animal studies have underlined the importance of major histocompatibility complex (MHC) genes in the susceptibility to bleomycin (BLM)-induced pulmonary fibrosis, the authors typed human leukocyte antigen-DR (HLA-DR) and tumor necrosis factor (TNF) genes in patients treated for Hodgkin's disease by a therapy including bleomycin.

Patients were divided into pulmonary responders (PR) (n=21) or nonresponders (PNR) (n=20) on the basis of pulmonary alterations detected on chest radiography and the cumulated amount of BLM injected. The incidence of TNFa2, a microsatellite allele in the promoter region of the TNFB gene reported to be associated with increased TNF-α production, was significantly higher in PR than PNR (65%versus19%). HLA-DRB1*15 showed a weak but nonsignificant association with the PR phenotype (50%versus14%), as well as HLA-DRB1*03 (30%versus19%) and TNFA-308*2 (30%versus14 %). TNFa2 and DR15 were independent risk factors and the occurrence of either genetic marker was 85%versus29% in the PR and PNR groups respectively.

Thus, the polymorphic TNFa2 microsatellite is associated with a risk of chemotherapy-induced pulmonary fibrosis.
Socioeconomic deprivation and asthma prevalence and severity in young adolescents
Authors: Poyser M.A. , Nelson H. , Ehrlich R.I. , Bateman E.D. , Parnell S. , Puterman A. , Weinberg E.
Published: October 2002

This study used the international study of asthma and allergies in childhood (ISAAC) to investigate the association between asthma and socioeconomic deprivation among young adolescents in Cape Town, South Africa.

The completed ISAAC written and video questionnaires of 4,706 13–14-yr-old school pupils were used. The prevalence of asthma symptoms was analysed by a local index of socioeconomic deprivation, based on residential location and defined on a 10-category scale from least to most deprived. Linear trends were examined visually and the prevalence odds ratio was used to summarize overall trends.

In general, the least socioeconomically deprived pupils reported higher prevalences of asthma symptoms “ever” and “in the last 12 months”. In contrast, the most socioeconomically deprived pupils reported higher asthma-symptom occurrence monthly or more frequently in the previous 12 months. A subgroup of pupils from low-income areas commuting to better-off schools showed the highest symptom prevalences.

The findings are consistent with a model in which an increase in the incidence of asthma is driven by factors associated with improved social circumstances, whereas severity is determined by factors associated with poverty. The impact of social mobility on asthma, including reporting of symptoms, deserves closer study.
Effects of antibiotics on protected specimen brush sampling in ventilator-associated pneumonia
Authors: Prats E. , Dorca J. , Pujol M. , Garcia L. , Barreiro B. , Verdaguer R. , Gudiol F. , Manresa F.
Published: October 2002

The effects of antibiotic treatment on the results of protected specimen brushing (PSB) in ventilator-associated pneumonia were prospectively assessed by performing this procedure before antibiotic treatment, and 12, 24, 48 and 72 h after initiation of antibiotic treatment, in 35 ventilated patients who developed pneumonia during mechanical ventilation.

The number of micro-organisms isolated, their concentration (colony-forming units (cfu)·mL−1), and the number of cases with a positive PSB (≥103 cfu·mL−1) were evaluated.

Within 12 h of the initiation of effective antibiotic treatment a rapid, significant decrease in the numbers of organisms isolated, their individual concentrations and the percentage of positive PSB results were observed. Certain bacterial species (Streptococcus pneumoniae,Haemophilus influenzee) appeared to be more vulnerable to antibiotics than others (Staphylococcus aureus,Pseudomonas aeruginosa,Acinetobacter baumanni).

This data confirms that prior antibiotic treatment, even after only a few hours of activity, significantly decreases the sensitivity of protected brush specimen; this effect appears to be particularly marked among the species involved in early ventilator associated pneumonia.
Frequency and clinical characteristics of rapid-onset fatal and near-fatal asthma
Authors: Plaza V. , Serrano J. , Picado C. , Sanchis J.
Published: October 2002

The onset of fatal and near-fatal asthma attacks can be rapid. The objective of this study was to determine the frequency and clinical characteristics of rapid-onset asthma (ROA) in patients suffering fatal and near-fatal crises.

Two-hundred and twenty patients with fatal or near-fatal attacks were enrolled in a multicentre, prospective study. ROA was defined as a crisis developing in ≤2 h. Data on patient and clinical characteristics were collected, and spirometric and allergy studies were performed when the patients were in a stable condition.

Forty-five attacks (20%) were ROA and 175 (80%) were slow-onset asthma (SOA). The triggers for SOA and ROA attacks were different, with the ROA group having a significantly lower rate of suspected respiratory infection (7%versus38%), higher rates of fume/irritant inhalation (9%versus1%) and a higher intake of nonsteroidal anti-inflammatory drugs (14%versus3%). The ROA group exhibited significantly higher rates of impaired consciousness (63%versus44%), absence of lung sounds upon admission (68%versus42%), fewer hours of mechanical ventilation (13 hversus28 h) and fewer days of hospitalization (8 daysversus9.5 days) than the SOA group.

The 20% frequency of rapid-onset fatal and near-fatal attacks in this study suggests that rapidly developing attacks may not be rare. These findings also support a distinct clinical profile for rapid-onset asthma marked by differences in triggers, severity of exacerbation and clinical course.
Bronchoscopic administration of bovine natural surfactant in ARDS and septic shock: impact on biophysical and biochemical surfactant properties
Authors: Günther A. , Schmidt R. , Harodt J. , Schmehl T. , Walmrath D. , Ruppert C. , Grimminger F. , Seeger W.
Published: October 2002

The purpose of the present study was to investigate the impact of bronchoscopic surfactant administration, on the biochemical and biophysical surfactant properties, in patients with severe and early acute respiratory distress syndrome (ARDS) and septic shock.

A total number of 27 ARDS patients received 300–500 mg·kg·body·weight−1of a natural bovine surfactant extract (Alveofact®)viaa flexible bronchoscope. Bronchoalveolar lavages were performed 3 h prior to, and 15–18 h and 72 h after surfactant administration. A comparison to healthy volunteers, undergoing an identical lavage procedure, was made (control, n=12).

Severe biophysical and biochemical surfactant abnormalities were encountered throughout in the ARDS patients. These included a massive alveolar protein load, a reduced percentage of large surfactant aggregates (LA), a loss of palmitoylated phosphatidylcholine species and a significant reduction of surfactant apoprotein (SP)-A, SP-B and SP-C in the LA fraction. Both minimum (γmin) and adsorption (γads) surface tension values (pulsating bubble surfactometer) were dramatically increased. Surfactant treatment resulted in a marked increase in the lavagable phospholipid (PL) pool, but predominance of the alveolar surfactant-inhibitory protein load was still encountered. Far-reaching or even complete normalization of the PL profile, the LA fraction and its SP-B and SP-C (but not SP-A) content as well as the fatty acid composition of the phosphatidylcholine class was noted. Surface tension lowering properties (γmin and γads) significantly improved, but were still not fully normalized.

Bronchoscopic administration of large quantities of natural bovine surfactant in severe acute respiratory distress syndrome causes far-reaching restoration of biochemical surfactant properties and significant improvement, however not full normalization, of biophysical surfactant function.
Survival of patients with biopsy-proven usual interstitial pneumonia and nonspecific interstitial pneumonia
Authors: Riha R.L. , Duhig E.E. , Clarke B.E. , Steele R.H. , Slaughter R.E. , Zimmerman P.V.
Published: October 2002

This is the first Australian study to examine survival and clinical characteristics in biopsy-proven idiopathic interstitial pneumonia.

A cohort of 70 patients from a single institution between January 1990 and December 1999 was reviewed.

All patients were Caucasian, 23 (33%) female. Mean age±sd at diagnosis was 60±12 yrs for males and 54±14 yrs for females. A total 24% of patients had never smoked. The histopathological diagnoses were usual interstitial pneumonia (UIP) (n=59), nonspecific interstitial pneumonia (NSIP) (n=7), desquamative interstitial pneumonia (n=3) and acute interstitial pneumonia (n=11). Clinical and functional characteristics of the two main histological subgroups of UIP and NSIP showed significantly older patients in the UIP group and a significantly lower mean forced expiratory volume in one second (FEV1) in the NSIP group. Median survival for UIP was 78 months compared with 178 months for NSIP. No survival difference between treated and untreated patients with UIP was found. Multivariate analysis revealed smoking alone to be predictive of poorer survival.

This study demonstrates the best median survival for usual interstitial pneumonia of available series and confirms a survival difference between usual interstitial pneumonia and nonspecific interstitial pneumonia. Furthermore, the reported results may have implications for treatment timing using conventional protocols currently recommended.
Computed tomography and magnetic resonance imaging: past, present and future
Authors: Müller N.L.
Published: October 2002

The aims of this paper are to summarize the current recommendations for the use of computed tomography (CT) and magnetic resonance imaging (MRI) in the chest and to suggest some possible future developments.

The main developments of CT in the chest have been the introduction of high-resolution CT (HRCT), spiral CT and, more recently, multidetector spiral CT.

HRCT is defined as thin-section CT (1‐ to 2‐mm collimation scans), optimized by using a high-spatial resolution (edge-enhancing) algorithm. Several studies have shown that HRCT closely reflects macroscopic (gross) pathological findings. HRCT currently has the best sensitivity and specificity of any imaging method used for the assessment of focal and diffuse lung diseases.

The advent of spiral CT and, more recently, multidetector CT scanners, has allowed for major improvements in the imaging of airways, pulmonary and systemic vessels, and lung nodules. Spiral CT facilitates multiplanar and three-dimensional display of structures and visualization of pulmonary and systemic vessels, with a level of detail that is comparable to that of conventional angiography. With the use of graphics-based software programs, spiral CT enables depiction of the luminal surface of the airways with images that resemble those of bronchoscopy (virtual bronchoscopy) or bronchography (virtual bronchography). Several studies have shown a high sensitivity and specificity for spiral CT in the diagnosis of acute pulmonary embolism. Therefore, spiral CT is rapidly becoming the imaging modality of choice in the diagnosis of pulmonary embolism.

Like the radiograph, signal intensity on computed tomography is mainly due to a single parameter: electron density. The signal intensity of the magnetic resonance image depends on four parameters: nuclear density, two relaxation times called T1 and T2, and motion of the nuclei within the imaged lung volume. Abnormal soft tissue can be identified more easily through measurement of these four parameters than through use of computed tomography. Furthermore, because the spatial orientation of the image is determined by manipulation of magnetic fields, scans can be performed in any plane. The main indications for magnetic resonance in the chest have been in the evaluation of the heart, major vessels, mediastinum, and hilar structures because of the natural contrast provided by flowing blood. Of particular interest for the respirologist has been the recent development of magnetic resonance angiography. This technique consists of three-dimensional single breath-hold images obtained using gadolinium-based contrast agents. This is a promising technique for the diagnosis of acute and chronic pulmonary embolism.
The prevalence of asthma and asthma-like symptoms among adults in rural Beijing, China
Authors: Chan-Yeung M. , Zhang L-X. , Tu D-H. , Li B. , He G-X. , Kauppinen R. , Nieminen M. , Enarson D.A.
Published: October 2002

No data have been reported on the prevalence of asthma in rural areas of China. The objective of the present study was to determine the prevalence of asthma-like symptoms, reported asthma and reported asthma attacks in rural Beijing, China, and to compare the prevalence in 20–44-yr-old participants with those reported for Canada and the European Community Respiratory Health Survey (ECRHS).

For a cross-sectional survey, 30 villages were randomly selected in the counties of Shunyi and Tongxian, 50 km north and east respectively of the city of Beijing and within the municipality of Beijing. The International Union Against Tuberculosis and Lung Disease questionnaire on bronchial symptoms translated into Chinese was completed by village doctors for each individual of >15 yrs. The survey was completed by 22,561 individuals, representing 98% of the eligible population.

The prevalence of asthma-like symptoms and reported asthma attacks was higher in females than in males and increased with age. Smoking significantly increased the prevalence of symptoms; the effect in females was greater than in males. Among the 20–44-yr-olds, the prevalence of reported asthma attacks in the previous 12 months was 0.67% in rural Beijing, very much lower than that reported in ECRHS centres (3.1%), urban Canada (6.9%) and semirural Canada (5.1%), after adjusting for age and sex. The prevalence of asthma-like symptoms was also very low in rural Beijing compared with ECRHS centres and Canada.

It is concluded that the prevalence of asthma-like symptoms and reported asthma was low in rural China compared with other countries, consistent with reports of the relative scarcity of asthma in farms and the “hygiene hypothesis”.
Imaging in lung cancer: positron emission tomography scan
Authors: Vansteenkiste J.F.
Published: October 2002

In the past 5 yrs, positron emission tomography (PET), usually used with
18
F-fluoro-2-deoxy-glucose (FDG), has become an important imaging modality in lung cancer patients.

Currently, the use of FDG-PET in respiratory oncology is mainly for diagnosis and staging. Standard indications are the evaluation of an indeterminate solitary pulmonary nodule or mass, where FDG-PET has proven to be significantly more accurate than computed tomography (CT) in the distinction between benign and malignant lesions. Several studies have also convincingly demonstrated that locoregional lymph node staging by FDG-PET (in correlation with CT images) is significantly superior to CT, with a negative predictive value equal or even superior to mediastinoscopy. FDG-PET also improves extrathoracic staging, through the detection of lesions missed at conventional imaging or characterization of lesions that remain equivocal on conventional imaging. Many European countries now have or plan reimbursement in these indications. Large-scale randomized studies should now focus on the impact this accurate tumour imaging technique has on treatment outcome and cost-efficacy.

Ongoing studies in specialized centres focus on the use of FDG-PET in more advanced clinical applications, such as planning radiotherapy, response evaluation after radiotherapy or (induction) chemotherapy, follow-up and early detection of recurrence, and prognostic information in this
in vivo
measurement of tumour glucose metabolism.

After a short note on the technique used and a summary of the current common indications of diagnosis and staging, this paper will deal mainly with two of the more advanced clinical applications of FDG-PET in locally advanced nonsmall cell lung cancer: radiation treatment planning and assessment of induction chemotherapy.

Finally, it should be mentioned that a whole new field of applications of positron emission tomography in molecular biology, using new radiopharmaceutical probes, is under extensive investigation. These techniques are promising for future use in very early response monitoring during chemo- or radiotherapy, in evaluation of novel molecular-targeted lung cancer therapies, or even gene therapy.
Role of secretory leukocyte protease inhibitor in the development of subclinical emphysema
Authors: Betsuyaku T. , Takeyabu K. , Tanino M. , Nishimura M.
Published: October 2002

Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. In some chronic airway diseases, the level of SLPI is decreased in sputum, leading to the continuation of neutrophil inflammation. In this study, the role of SLPI in subclinical pulmonary emphysema was examined.

Sequential bronchoalveolar lavage was performed in an attempt to separately evaluate the levels of SLPI in the large airways and in the peripheral airways for two groups of smokers. One group had subclinical emphysema by computed-tomography scans and one group did not. SLPI localized in alveolar macrophages (AM) was also assessed.

The level of SLPI was significantly elevated in the peripheral airways from the subjects with emphysema compared to those without emphysema (1589.2±353.9versus729.1±31.0 ng·mL−1), although it was similar in the large airways (3442.3±499.6versus2535.7±578.8 ng·mL−1). There was a trend for higher amount of SLPI to be released from AM in subjects with subclinical emphysema, although this did not reach statistical significance.

In conclusion, there is compensatory upregulation of secretory leukocyte protease inhibitor in peripheral airways in subclinical pulmonary emphysema, which is in sharp contrast to the decreased level of secretory leukocyte protease inhibitor reported in some chronic airway diseases.
Ambroxol suppresses influenza-virus proliferation in the mouse airway by increasing antiviral factor levels
Authors: Yang B. , Yao D.F. , Ohuchi M. , Ide M. , Yano M. , Okumura Y. , Kido H.
Published: October 2002

The protective effect of ambroxol, a mucolytic agent which has antioxidant properties and stimulates the release of pulmonary surfactant, against influenza-virus proliferation in the airway was investigated in mice.

Ambroxol or the vehicle was administered intraperitoneally twice a day for 5–7 days to mice shortly after intranasal infection with a lethal dose of influenza A/Aichi/68 (H3N2) virus, and the survival rate, virus titre and levels of factors regulating virus proliferation in the airway fluid were analysed.

Ambroxol significantly suppressed virus multiplication and improved the survival rate of mice. The effect of ambroxol reached a peak at 10 mg·kg−1·day−1, higher doses being less effective. Ambroxol stimulated the release of suppressors of influenza-virus multiplication, such as pulmonary surfactant, mucus protease inhibitor, immunoglobulin (Ig)-A and IgG, although it stimulated the release of a trypsin-type protease that potentiates virus proliferation. In addition, ambroxol transiently suppressed release of the cytokines, tumour necrosis factor-α, interferon-γ and interleukin-12, into airway fluid.

Although ambroxol had several negative effects on the host defence system, overall it strikingly increased the concentrations of suppressors of influenza-virus multiplication in the airway.
Annual lung function changes in young patients with chronic lung disease
Authors: Merkus P.J.F.M. , Tiddens H.A.W.M. , de Jongste J.C.
Published: October 2002

Reference equations for ventilatory function that use different statistical models may introduce artifacts that affect the estimated change of lung function during growth in young subjects. The effect of differently modelled reference equations on the estimated annual change of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in young patients with chronic lung disease was assessed.

Four frequently used reference equations were used to describe the longitudinal changes of FEV1and FVC in 52 patients (23 females) with cystic fibrosis (CF) during a mean follow-up of 3.9 yrs.

Choice of reference equations directly affected value and, most importantly, estimated annual change of FVC and FEV1. Mean±sd annual change of FEV1varied from 2.2±6.2 to −2.2±3.6% of predicted. For two reference equations the estimated individual changes of FEV1and FVC in CF were positively correlated with mean individual age. This probably reflects underestimation of deteriorating lung function.

Variability of annual change was independent of age only when reference equations that were designed to accurately predict lung function during the pubertal growth spurt were used. These findings have implications for patient care and clinical research.
Trends in prevalence of atopic diseases and allergic sensitization in children in Eastern Germany
Authors: Heinrich J. , Hoelscher B. , Frye C. , Meyer I. , Wjst M. , Wichmann H-E.
Published: October 2002

Trends in prevalence of atopic diseases and allergic sensitization in children from Eastern Germany during the 1990s were analysed.

The study consisted of three regional cross-sectional surveys of a total of 7,632 children (aged 5–14 yrs) in 1992–1993, 1995–1996, and 1998–1999. Information was gathered on atopic diseases and potential predictors by a parental questionnaire. Allergic sensitization for birch, grass, mite, cat, and cladosporium were assessed by radioallergosorbent test (RAST).

After adjustment for age, sex and the study area of the participants, prevalence increased between the first and third survey for hay fever, for asthma and for atopic eczema. The adjusted prevalence of allergic sensitization (RAST >0.35 kU·L−1) showed a decrease, whereas the prevalence of strong sensitization (RAST ≥17.5 kU·L−1) increased significantly, specifically in cohorts born after 1989. Further adjustment for possible determinants of these atopic diseases did not change the trend estimates.

A clear increase in the prevalence of atopic diseases, with the exception of hay fever, was observed as well as a shift towards a stronger allergic sensitization, which might affect the onset of clinical manifestations of atopic diseases.

Differences in the epidemiology of respiratory symptoms, illnesses and allergies between populations living in the former East Germany and those living in the former West Germany have been reported. Among East German children, lower prevalence rates of asthma, and positive skin-prick tests were observed compared to West German children in the early 1990s 1–5. Similarly, among East German adults, lower specific immunoglobulin (Ig) E levels and lower prevalence rates of asthma, wheezing, positive methacholine-challenge tests, allergic rhinitis, and positive skin-prick tests have been reported compared to those of West German adults 6, 7.
Glutathione deficiency of the lower respiratory tract in patients with idiopathic pulmonary fibrosis
Authors: Beeh K.M. , Beier J. , Haas I.C. , Kornmann O. , Micke P. , Buhl R.
Published: October 2002

Idiopathic pulmonary fibrosis (IPF) is a disease of unknown aetiology. Increased oxidant burden and antioxidant,e.g.glutathione (GSH), deficiency in the lower respiratory tract have been thought to play a role in the progression of IPF. Sputum induction is a safe noninvasive tool to study inflammation in the respiratory tract.

The aim of the present study was to evaluate the direct measurement of GSH in induced sputum supernatant. Sixteen IPF patients and 15 healthy, nonsmoking subjects underwent sputum induction. Total GSH in sputum, saliva and plasma was measured spectrophotometrically.

Sputum GSH was decreased more then four-fold in IPF patients when compared to healthy subjects (mean GSH 1.4±0.34 µMversus5.8±0.98 µM). Salivary GSH was generally low or undetectable in all subjects. Plasma GSH levels were lower in IPF patients (0.26±0.1versus0.74±0.16 µM). In IPF patients, there was a borderline correlation of sputum GSH levels with disease duration and lung-function impairment.

These data confirm the established role of oxidant/antioxidant imbalance in the pathogenesis of idiopathic pulmonary fibrosis, and show the potential of induced sputum to directly study inflammatory processes and surrogate markers in interstitial lung diseases like idiopathic pulmonary fibrosis.
The correlation of emphysema or airway obstruction with the risk of lung cancer: a matched case-controlled study
Authors: Kishi K. , Gurney J.W. , Schroeder D.R. , Scanlon P.D. , Swensen S.J. , Jett J.R.
Published: October 2002

A matched case-controlled study was conducted to determine if airway obstruction or emphysema were associated with an increased risk of lung cancer.

Lung cancer cases (n=24) were identified through a low-dose spiral computed tomography (CT) screening trial from 1,520 participants. Four controls without lung cancer were selected for each case from the participants and matched by sex, age and smoking history. Emphysema was assessed by quantitative CT analysis. Conditional logistic regression was employed to assess results of spirometry and CT quantitative analysis as potential risk factors for lung cancer.

The likelihood of lung cancer was found to be significantly increased for those with forced expiratory volume in one second (FEV1) ≤40% of predicted. The results suggested that a lower percentage of predicted FEV1was indicative of lung cancer. No compelling evidence was found to suggest that the percentage of emphysema was associated with lung cancer.

These results suggest an increased risk of lung cancer associated with airway obstruction. However, percentage of emphysema as determined by computed tomography was not associated with an increased risk of lung cancer.
Contribution of respiratory acidosis to diaphragmatic fatigue at exercise
Authors: Jonville S. , Delpech N. , Denjean A.
Published: October 2002

The factors that may modulate ventilatory muscle fatigue during exercise are controversial. In this study the contribution of acidosis to exercise-induced diaphragmatic fatigue was investigated, using measurements of the twitch mouth pressure response (tw,Pmo) to cervical magnetic stimulation.

After learning sessions, 14 healthy subjects performed two cycling tests (at 60% of maximal aerobic power for 16 min), one while breathing spontaneously (mean minute ventilation (V′e) 67.9 L·min−1) and the other while hypoventilating voluntarily (meanV′E53.8 L·min−1). Exercise was voluntarily set at a moderate power to avoid a fatiguing effect of exerciseper se.

As compared with spontaneous breathing (SB), voluntary hypoventilation (VHV) significantly increased mean carbon dioxide tension in arterial blood (Pa,CO2) (51 mmHgversus41 mmHg) and significantly decreased arterial pH (7.28versus7.34). After 10 min of SB test, tw,Pmowas unchanged compared to the baseline value (19.1versus18.5 cmH2O) whereas tw,Pmofell significantly as compared to baseline (17.1versus18.5 cmH2O) and to SB (17.1versus19.1 cmH2O) after the VHV test.

The results of this study suggest that exposure to hypercapnia may impair respiratory muscle function. This impairment could be more clinically relevant in patients with chronic obstructive lung disease.
Imaging techniques in treatment algorithms of pulmonary embolism
Authors: Pistolesi M. , Miniati M.
Published: October 2002

Pulmonary embolism (PE) is more often diagnosedpost mortemby pathologists thanin vivoby clinicians. The identification of practical diagnostic algorithms could reduce the rate of diagnoses first made at autopsy.

The literature was reviewed for evidence-based approaches to PE diagnosis. Since the PE mortality rate greatly exceeds that of deep vein thrombosis (DVT), more emphasis was given to reports specifically dealing with PE diagnosis by objective pulmonary vascular imaging techniques than to those aimed at DVT detection.

Several studies have shown that standardized clinical estimates can be effectively used to give a pretest probability to calculate, after appropriate objective testing, the post-test probability of PE. A prospective trial has shown that perfusion scanning, rather than ventilation/perfusion scanning, should be the imaging technique of first choice for the management of patients suspected of having PE. The clinical usefulness of spiral computed tomography has not as yet been firmly established. However, ongoing technological developments would probably render the technique accurate enough to replace conventional angiography.

The authors propose a noninvasive diagnostic algorithm with high predictive accuracy (positive predictive value 96%; negative predictive value 98%) starting with a standardized assessment of clinical likelihood, followed by a perfusion scan and, eventually, spiral computed tomography in only a minority of patients (<20%) with discordant clinical and scintigraphic findings.
Modern treatment of pulmonary embolism
Authors: Goldhaber S.Z.
Published: October 2002

Modern treatment of acute pulmonary embolism requires rapid and accurate diagnosis followed by risk stratification to devise an optimal management strategy. Patients at low risk have good outcomes simply with intensive anticoagulation treatment. Higher-risk patients may require more aggressive intervention with thrombolysis or embolectomy.

Clinical risk factors for an adverse outcome include increasing age, cancer, congestive heart failure, systemic arterial hypotension, chronic obstructive pulmonary disease and right ventricular dysfunction. A promising approach is the Geneva Prognostic Score, which is based upon a rapid clinical assessment.

On physical examination, signs of right ventricular failure, including distended jugular veins and a right-sided S3gallop, should be looked for. The electrocardiogram may show evidence of right ventricular strain with a new right bundle branch block or T wave inversion in leads V1–V4. The troponin level may be elevated as a marker of cardiac injury and right ventricular microinfarction, even in the absence of coronary artery disease. The most useful imaging marker of high risk is the presence of moderate or severe right ventricular dilatation and hypokinesis on the echocardiogram, especially with progressively worsening right ventricular function despite intensive anticoagulation treatment.

Patients at high risk should be considered for thrombolytic therapy or embolectomy rather than management with anticoagulation therapy alone. Special care must be taken to avoid thrombolytic therapy among patients who might be susceptible to intracranial haemorrhage. Intracranial haemorrhage reached a surprisingly high rate of 3.0% in the International Cooperative Pulmonary Embolism Registry of 2,454 prospectively evaluated acute pulmonary embolism patients at 52 hospitals in seven countries. An alternative approach to patients at high risk is a catheter-based or open surgical embolectomy. It is crucial to refer these patients as quickly as possible, rather than delaying intervention until cardiogenic shock has ensued. Fortunately the current tools for risk stratification provide an “early window” for prognostication and can help the coordination of a definitive treatment plan with optimal results.