bluuebunny/crossref_metadata_2025 huggingface dataset:
Lower prevalence of asthma and atopy in Turkish children living in Germany
Authors: Kabesch M , Schaal W , Nicolai T , von Mutius E
Published: September 2002

Ethnic origin has been reported to affect the prevalence of atopic diseases in several studies in different parts of the world. However, little is known about the prevalence of asthma and atopy in immigrants living in Europe. The objective of this study was to evaluate the prevalence of asthma and atopy in Turkish children living in Germany and to investigate the role of ethnic origin on the development of asthma and atopy in this population. In a cross-sectional survey the prevalence of physician-diagnosed asthma, atopy, skin-prick tests and bronchial hyperresponsiveness (BHR) to cold dry air challenge was assessed in 7,445 school children aged 9-11 yrs, living in Munich, south Germany. Questionnaires were distributed to the parents for self-completion and children underwent skin prick tests and cold air hyperventilation challenge. The Turkish children showed a significantly lower prevalence of asthma (5.3 versus 9.4%, p<0.05) than their German peers. Furthermore, atopy, as assessed by skin prick tests (24.7 versus 36.7%, p<0.001) and BHR (3.9 versus 7.7%, p<0.001), was less common in Turkish children. In multivariate regression models controlling for potential explanatory factors, Turkish origin still showed a significantly lower risk of developing asthma, atopic sensitization and BHR. The prevalence of childhood asthma was therefore shown to be lower in Turkish children living in Germany than in Turkey. These findings suggest that the lower prevalence of asthma and allergy in Turkish children living in Germany might be attributable to a selection bias affecting the parents of these children, as healthy individuals may have decided to come to Germany for work.
Domestic aeroallergen exposures among infants in an English town
Authors: Atkinson W , Harris J , Mills P , Moffat S , White C , Lynch O , Jones M , Cullinan P , Newman Taylor AJ
Published: September 2002

A multicentre, prospective cohort study of childhood asthma was established in three European countries; the purpose of the project is the examination of factors which modify the relationship between allergen exposure in infant life and subsequent atopy and asthma. Dust samples were collected from the homes of 643 infants in a single town in the UK (the first cohort) and assayed for house dust mites (Der p 1) and cat allergen (Fel d 1) concentrations by enzyme-linked immunosorbent assay. A questionnaire with potential relevance to the development of atopy and asthma was completed. A wide variation in exposure to both allergens was observed. Carpeted, double-glazed or damp living rooms, and those sampled in the winter months, had higher levels of Der p 1, but these features did not predict Fel d 1 concentrations. Measures of high home occupancy were positively related to Der p 1 concentrations; and inversely with levels of Fel d 1, a finding which could not be explained by cat ownership. Homes in which one or more persons smoked had significantly lower concentrations of Der p 1, but not Fel d 1. There were no consistent differences in allergen levels between homes where one or more parent or sibling was either atopic or asthmatic. These findings indicate complex interactions among domestic, behavioural and seasonal factors and early allergen exposure in British children.
The effects of surgically treated pulmonary stenosis on lung growth and cardiopulmonary function in children during rest and exercise
Authors: Rosenthal M , Bush A
Published: September 2002

The effects of high pulmonary blood flow and pressure on pulmonary development are well understood, but the effect of low pulmonary flow/pressure is not. Pulmonary stenosis (PS) was therefore used as a model to determine its effect on lung development, which was assessed noninvasively by carbon monoxide transfer at rest and during exercise. One hundred and six control children (55 males, 8-16 yrs) and 11 children with isolated valvar or subvalvar PS surgically corrected > or =10 yrs prior to the study without residual stenosis/regurgitation were evaluated. Measurements of effective pulmonary blood flow, stroke volume, arteriovenous oxygen difference (AVO), transfer factor and transfer constant, alveolar ventilation and anaerobic threshold were performed using a mass spectrometer. Data from the normal children allowed calculation of z-scores for the study group matched for age, sex, pubertal stage and surface area. PS children at rest had a significantly lower forced expired volume in one second, cardiac frequency and transfer constant with a raised oxygen consumption and AVO which persisted on exercise. During exercise, the cardiac frequency was 12 beats x min(-1) slower and AVO 0.017 L greater than controls (p<0.05). A persistently mildly raised effective functional residual capacity (0.2 L x m(-2)) during exercise led to a reduced transfer constant (0.35 mmol x min(-1) x kPa(-1) x L(-1)), although the percentage rise (28%) from rest to peak exercise was normal. The percentage fall in stroke volume from the penultimate exercise stage to peak exercise stage was greater in PS children (24%, 95% confidence interval 11-37) than control children (2.4, -2-10, p<0.005). In conclusion, although the effects are small, pulmonary stenosis does affect cardiopulmonary function after surgery. This needs to be considered when contemplating the timing of treatment.
Pulmonary function abnormalities in children with Henoch-Schonlein purpura
Authors: Cazzato S , Bernardi F , Cinti C , Tassinari D , Canzi A , Bergamaschi R , Corsini I , Capecchi V , Cacciari E
Published: September 2002

Henoch-Schonlein purpura (HSP) is a widespread necrotizing vasculitis affecting small vessels characterized by nonthrombocytopenic purpura. Pulmonary involvement is a rare fatal complication with diffuse alveolar haemorrhage. The objective of this study was to evaluate possible early lung function abnormalities and to establish any relationship with the clinical activity of the disease. Fifteen children with HSP and without clinical or radiological evidence of lung involvement underwent pulmonary function study at the onset of the disease. A sample of 28 subjects matched by age, height, and weight was chosen as a control group. After a mean of 21 months (range 12-43) lung function tests were repeated in 10 of the previously studied children. During the acute phase of the disease the transfer factor for carbon monoxide, measured by steady-state (TL,COss) and single-breath (TL,COsb) methods, was found to be significantly lower in children with HSP than control subjects. There was no significant relationship between pulmonary function tests with symptoms and signs at onset, nor was there any correlation between variables and serum immunoglobulin A (IgA) concentration. In all but two patients, clinical recovery was observed within 6 weeks from the onset of the disease. In one case relapses of purpuric skin lesions were observed during the first 3 months of follow-up. The second case had relapses of purpuric skin lesions and microscopical haematuria during the 12 months following the onset of the disease with characteristic IgA mesangial deposition on renal biopsy. Although the overall mean value of TL,COsb improved from baseline to the second investigation, in both patients the recurrences of clinical signs were associated with a slight impairment of TL,COsb at the second evaluation. These data suggest an early subclinical lung impairment in children with Henoch-Schonlein purpura during the active phase of the disease. The presence of isolated pulmonary function abnormalities was not associated with the subsequent development of lung disease.
Respiratory function in patients with thalassaemia and iron overload
Authors: Dimopoulou I , Kremastinos DT , Maris TG , Mavrogeni S , Tzelepis GE
Published: September 2002

Iron deposition in the respiratory system has been proposed as a potential cause of the ventilatory restrictive impairment seen in patients with thalassaemia major (TM) and iron overload. In this study, magnetic resonance imaging (MRI) measurements of the liver (T2 relaxation time) were used as a surrogate index of total body iron burden and the extent to which these measurements correlated with total lung capacity (TLC) in patients with TM was examined. Twenty-one patients (aged 25+/-5 yrs) with TM participated in the study. Standard pulmonary function tests were undertaken and the T2 relaxation time of the liver was measured in all patients. Ventilatory restrictive impairment (mean TLC 74+/-11 (SD)% predicted) was the most common abnormality found in 71% of TM patients. There was no correlation between TLC (% pred) and T2 relaxation time (r=0.06, p=0.78). T2 relaxation time correlated weakly with average serum ferritin levels (r=-0.56, p=0.008). In conclusion, the data do not support the notion that the restrictive impairment in patients with thalassaemia major and iron overload is related to iron deposition in the respiratory system.
Differences in spirometry reference values: a statistical comparison of a Mongolian and a Caucasian study
Authors: Crapo RO , Jensen RL , Oyunchimeg M , Tsh T , DuWayne Schmidt C
Published: September 2002

New reference value studies for spirometry are commonly compared to existing reference value studies using average data derived from existing reference equations. Such comparisons are inherently flawed because they do not account for differences in distributions of the independent and dependent variables and they do not have identical methodologies. This study was undertaken 1) to derive reference equations for forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) for natives of Mongolia and 2) to compare the Mongolian data with data from a 1981 reference study of Caucasians in Salt Lake City, UT, USA. Spirometry was performed on 344 (176 male, 168 female) healthy, nonsmoking urban natives of Mongolia to generate reference equations for FVC, FEV1, and FEV1/FVC. These data were compared with data from a 1981 reference study of Caucasians in Salt Lake City, using both an analysis of covariance of the raw data and parametric and nonparametric comparisons of a matched pair subset. Average measured forced vital capacity and forced expiratory volume in one second in native Mongolians were within 1-2% of the Caucasian predicted values. These small differences are not statistically significant in any of the multiple methods of comparisons. Power analysis suggests that, if real differences exist, the differences in forced vital capacity are <155 mL for males, <105 mL for females, and the differences in forced expiratory volume in one second are <107 mL for males and <76 mL for females.
Cardiorespiratory efficacy of thrombolytic therapy in acute massive pulmonary embolism: identification of predictive factors
Authors: Michard F , Meyer G , Wysocki M , Diehl JL , Mercat A , Sors H
Published: September 2002

The aim of this study was to evaluate the contribution of clinical, angiographic and haemodynamic findings in predicting the cardiorespiratory efficacy of thrombolytic therapy in acute massive pulmonary embolism. Haemodynamic measurements and pulmonary angiography were performed before (H0) and 12 h after (H12) initiating thrombolytic therapy in 23 patients with acute massive pulmonary embolism (Miller index > or =20/34), and free of prior cardiopulmonary disease. Patients were divided into two groups according to the variation in oxygen delivery (deltaDO2) between H0 and H12: deltaDO2 >20% (responders, n=10) and deltaDO2 < or =20% (nonresponders, n=13). Before thrombolysis, clinical and angiographic findings were similar in both groups. Mean right atrial pressure (RAP) and total pulmonary (vascular) resistance (TPR) were higher, while cardiac index (CI), DO2 and mixed venous oxygen saturation (Sv,O2) were lower in responders. DO2 and Sv,O2 were more closely correlated with deltaDO2 than RAP, TPR and CI. Eight out of the 10 responders and two out of the 13 nonresponders had an Sv,O2 <55%, while nine of the responders and two of the nonresponders had a DO2 <350 mL x min(-1) x m(-2). In conclusion, the initial oxygen delivery and mixed venous oxygen saturation may predict the cardiorespiratory efficacy of thrombolytic therapy in acute massive pulmonary embolism. When pulmonary angiography is performed, measurement of mixed venous oxygen saturation may be a simple method by which to select patients for thrombolytic therapy.
Proximal pulmonary emboli modify right ventricular ejection pattern
Authors: Torbicki A , Kurzyna M , Ciurzynski M , Pruszczyk P , Pacho R , Kuch-Wocial A , Szulc M
Published: September 2002

Analysis of the systolic flow velocity curve (SFVC) in the right ventricular outflow tract is considered as an alternative to the tricuspid valve pressure gradient (TVPG) method for echo-Doppler assessment of pulmonary arterial pressure (P(pa)). The present study checked whether or not SFVC is affected by the cause of pulmonary hypertension. Doppler recordings of 86 patients (39 female, aged 55.5+/-15.2 yrs) with acute (AP-PE) or chronic (CP-PE) proximal pulmonary embolism, chronic obstructive pulmonary disase (COPD) or primary pulmonary hypertension (PPH) were retrospectively analysed by two observers unaware of the purpose of the study. Despite having the lowest TVPG (48+/-13 mmHg), patients with AP-PE had the shortest acceleration time (t(acc); 56+/-15 ms) and time to midsystolic deceleration (t(msd); 105+/-16 ms). t(acc) <60 ms in patients with TVPG <60 mmHg had 98% specificity and 48% sensitivity for AP-PE. In PPH, SFVC was less abnormal (t(acc) 64+/-14 ms, t(msd) 125+/-25 ms, both p<0.03) despite having a TVPG twice as high (92+/-12 mmHg, p< 0.001). In contrast to t(acc), TVPG showed strong correlation with direct P(pa) measurements whenever performed (r=-0.43, p=0.02, versus r=0.80, p<0.001; n=30). There was no correlation between t(acc) and TVPG in a pooled study group and SFVC seemed strongly affected by the presence of both AP-PE and CP-PE. While potentially useful for evaluation of the true right ventricular afterload during pulsatile flow conditions, the systolic flow velocity curve does not provide a reliable estimate of pulmonary arterial pressure.
Exercise training does not alter acetylcholine-induced responses in isolated pulmonary artery from rat
Authors: Mitani Y , Maruyama J , Maruyama K , Sakurai M
Published: September 2002

In chronic exercise-trained animals, acetylcholine (ACh)-stimulated endothelial nitric oxide (NO) release is enhanced in the systemic circulation. The purpose of the present study was to determine whether chronic exercise training also enhances NO-mediated relaxation in rat pulmonary artery. Sprague-Dawley rats were randomly divided into groups of exercise-trained and sedentary control rats. The exercise-trained rats ran on a motor-driven treadmill at 30 m x min(-1) up a 15 degree incline 10-60 min x day(-1), 5 days per week for 10 weeks, and had less body weight, lower serum total cholesterol and triglyceride levels than sedentary rats. Contraction induced by potassium chloride and prostaglandin (PG)F2alpha were similar between isolated conduit pulmonary arterial rings from sedentary and exercise-trained rats. There were no differences between PGF2alpha-precontracted rings from sedentary and exercise trained rats in both ACh and sodium nitroprusside-induced relaxations. The NO synthase inhibitor, nitro-L-arginine, suppressed ACh-induced relaxation in both sedentary and exercise-trained rats. These results suggested chronic exercise training did not alter the acetylcholine-induced endothelial NO production and release and the sensitivity of vascular smooth muscle cell to NO in isolated conduit pulmonary artery of rat.
Bronchoscopy and bronchoalveolar lavage findings in cross-country skiers with and without "ski asthma"
Authors: Sue-Chu M , Larsson L , Moen T , Rennard SI , Bjermer L
Published: September 2002

Bronchial hyperresponsiveness to methacholine with asthma-like symptoms ("ski asthma") is frequent in elite cross-country skiers. To further the understanding of "ski asthma", 10 nonasthmatic, nonatopic controls and 30 adolescent elite skiers were investigated by bronchoscopy and bronchoalveolar lavage (BAL). Nine skiers were atopic without allergy symptoms. Compared with controls, the macroscopic inflammatory index in the proximal airways in skiers was three-fold greater (median (interquartile range) 3.0 (2.0-5.0) versus 1.0 (0.8-2.3), p=0.008). In the BAL fluid, skiers had significantly greater total cell (p<0.05) and percentage lymphocyte (p<0.01) and mast cell counts (p<0.05). Neutrophil and eosinophil counts were not significantly different and eosinophil cationic protein was not detected. Tumour necrosis factor-alpha and myeloperoxidase were detected in 12 (40%) and six (20%) skiers, respectively. In skiers with ski asthma, the inflammatory index was greater than in nonasthmatic skiers. Lymphocyte subtypes and activation markers, and concentration of albumin, fibronectin and hyaluronan were not different from those in controls. Cross-country skiers have a minor to moderate degree of macroscopic inflammation in the proximal airways at bronchoscopy and a bronchoalveolar lavage fluid profile which differs in several respects from healthy controls. Skiers with ski asthma tend to show even higher degrees of bronchial inflammation.
Alpha2-macroglobulin and eosinophil cationic protein in the allergic airway mucosa in seasonal allergic rhinitis
Authors: Meyer P , Persson CG , Andersson M , Wollmer P , Linden M , Svensson C , Greiff L
Published: September 2002

As previously demonstrated in seasonal allergic rhinitis, increased microvascular permeability and eosinophil activation are key features of allergic airway inflammation. In the present study, the hypothesis that exudation of alpha2-macroglobulin may cause the appearance of eosinophil cationic protein (ECP) in the airway lumen was explored. Nasal lavages were carried out using the nasal pool device before and during the pollen season both at baseline and after histamine challenge in 10 children with allergic rhinitis. Nasal lavage fluid levels of alpha2-macroglobulin and ECP were determined. All patients experienced nasal symptoms of allergic rhinitis during the pollen season (p<0.01-0.05). Baseline nasal lavage fluid levels of alpha2-macroglobulin and ECP were increased during the season (p<0.01-0.05) and were found to be well correlated (p<0.0001). Histamine produced concentration-dependent plasma exudation before and during the pollen season, but it was only during the pollen season that this caused an increase in the lavage fluid levels of ECP (p<0.05). These data suggest that exudation of plasma and increased tissue levels and output of eosinophil cationic protein characterize nasal mucosal inflammation in children with seasonal allergic rhinitis. The plasma exudation process in part may account for lumenal entry of eosinophil cationic protein molecules that have been released in mucosal tissue compartments. A combination of induced exudation and nasal lavage may improve the yield of important markers of inflammation in studies of nasal diseases.
Dynamics of eicosanoids in peripheral blood cells during bronchial provocation in aspirin-intolerant asthmatics
Authors: Schafer D , Schmid M , Gode UC , Baenkler HW
Published: September 2002

The underlying mechanisms of bronchoconstriction in aspirin-intolerant asthmatics (AIAs) are still unknown, but the hypothesis of an altered metabolism of arachidonic acid is generally accepted. So far, no in vitro test for aspirin intolerance is available. The hypothesis that the profile of eicosanoid mediators is changed in AIA-even before aspirin challenge was tested. The release of prostaglandin E2 (PGE2), peptidoleukotrienes and histamine was measured using competitive enzyme immunoassays in 10 asthmatics with a history of aspirin intolerance, 10 controls and eight aspirin-tolerant asthmatics (ATAs) before and after bronchial provocation with lysine-aspirin. Comparing basal release of eicosanoids before challenge, peptidoleukotrienes were significantly elevated and PGE2 was vastly reduced in AIAs, whereas ATAs had elevated basal peptidoleukotrienes but only slightly reduced basal PGE2. The decrease in forced expiratory volume in one second (FEV1) was not associated with changes in histamine release. After aspirin challenge, there was a massive increase of already elevated peptidoleukotrienes in AIAs, but not in ATAs. Arachidonic acid-induced PGE2 release in AIAs was not significantly changed, whereas it was significantly reduced in ATAs and healthy controls. Histamine release was unaffected by aspirin challenge in all three groups. There is a typically altered profile of eicosanoids in aspirin-intolerant asthmatics which could make in vitro diagnosis of aspirin intolerance possible.
Induced sputum in adolescents with severe stable asthma. Safety and the relationship of cell counts and eosinophil cationic protein to clinical severity
Authors: Grootendorst DC , van den Bos JW , Romeijn JJ , Veselic-Charvat M , Duiverman EJ , Vrijlandt EJ , Sterk PJ , Roldaan AC
Published: September 2002

This study examined the safety of sputum induction and the relation between sputum cell counts and clinical parameters in adolescents with severe persistent asthma. Within 5 days, induced sputum and reversibility in forced expiratory volume in one second (FEV1), quality of life, provocative concentration causing a 20% fall in FEV1 (PC20) of adenosine monophosphate and histamine, exercise-induced bronchoconstriction, overall asthma severity index, and blood eosinophils were collected in 20 atopic adolescents with moderate-to-severe persistent asthma (12-18 yrs of age, FEV1 65-110% of predicted, on 500-2,000 microg inhaled steroids daily). FEV1 was reversible by 13.3-2.3% pred. After sputum induction, FEV1 was still increased by 9.0+/-2.6% pred as compared to the pre-salbutamol baseline. Sputum contained, median (range): 12.4 (0.4-59.5)% squamous cells, 47.3 (6.8-84.0)% macrophages, 39.0 (4.6-84.8)% neutrophils, 4.8 (1.0-12.4)% lymphocytes, 0.4 (0-10.8)% eosinophils and 3.6 (0-23.4)% bronchial epithelial cells. Sputum eosinophils showed a trend towards a significant association with the overall asthma severity index (r=0.46, p=0.06) and correlated inversely with baseline FEV1 (r=-0.51, p=0.03). In conclusion, sputum can be induced safely in adolescents with moderate-to-severe persistent asthma, if pretreated with beta2-agonists. Despite relatively low sputum eosinophil counts in these patients on inhaled steroids, the association of eosinophil numbers with baseline forced expiratory volume in one second and asthma severity index favours a role of induced sputum in monitoring adolescents with severe asthma.
Sensitivity and exposure to indoor allergens in adults with differing asthma severity
Authors: Tunnicliffe WS , Fletcher TJ , Hammond K , Roberts K , Custovic A , Simpson A , Woodcock A , Ayres JG
Published: September 2002

In asthma, it is uncertain whether there is an association between degrees of exposure to domestic allergens and asthma severity. The pattern of sensitivity and exposure to common indoor allergens was examined in subjects with differing asthma severity. Sensitivity to house dust mite, dog and cat allergen and exposure to Der p 1, Can f 1 and Fel d 1 were assessed by skin prick tests and settled dust analysis in 28 subjects with severe asthma and 28 age- and sex-matched subjects with mild asthma (two declined skin prick test). All severe asthmatic subjects had at least one positive skin test and 20 of the 28 subjects were positive to all three allergens. Fourteen of the 26 subjects with mild asthma who took skin prick tests were positive to at least one, and one of these subjects was positive to the three allergens tested. Except for bedroom Fel d 1, the proportion of severe asthmatics both sensitized and exposed to each allergen at each site was significantly greater than the proportion sensitized and exposed in the mild asthma group. The geometric mean allergen concentrations, with the exception of bedroom Fel d 1, were greater in sensitized severe asthmatics than the sensitized mild asthmatics, which was significant for Der p 1 in bedroom samples and Can f 1 in bedroom and living room samples. These results support an association between the degrees of domestic allergen exposure in sensitized individuals and asthma severity.
The effect of processing on inflammatory markers in induced sputum
Authors: Louis R , Shute J , Goldring K , Perks B , Lau LC , Radermecker M , Djukanovic R
Published: September 2002

The effects of the mucolytic agent, dithioerythritol (DTE), and the temperature at which sputum processing is conducted on cellular and biochemical markers in induced sputum was assessed. Samples from healthy and atopic asthmatic subjects were treated with either DTE or phosphate-buffered saline (PBS) at 22 or 37 degrees C and compared for cell counts and concentrations of histamine, tryptase, eosinophil cationic protein (ECP), free interleukin (IL)-8, immunoglobulin (Ig)A, IL-8/IgA complexes and secretory component (SC). In addition, the influence of DTE on in vitro mediator release from blood eosinophils, basophils and bronchoalveolar lavage (BAL) mast cells was studied. Processing with DTE improved cytospin quality and increased the cell yield and measurable ECP, tryptase, IgA and SC, but reduced levels of histamine in PBS-treated samples and had no effect on IL-8. Cell counts or mediator levels were similar when sputum was processed at 22 or 37 degrees C, even though DTE induced blood basophils and BAL mast cells to release histamine at 37 degrees C. In spiking experiments, recovery of added ECP, tryptase, total IL-8 and histamine from sputum was similar in DTE- and PBS-processed sputum, but reduced for free IL-8 in PBS-treated samples. In conclusion, dithioerythritol improves cell and mediator recovery without causing cell activation when sputum processing is conducted at room temperature. The extent of recovery depends on the mediator studied.
Aerosol recovery from large-volume reservoir delivery systems is highly dependent on the static properties of the reservoir
Authors: van der Veen MJ , van der Zee JS
Published: September 2002

In this study, the role of electrostatic fields on aerosol recovery from a system with a large collapsible reservoir (30 L) was investigated. In addition, the efficacy of the reservoir method for bronchial challenge procedures was assessed in vivo. Aerosol recovery was determined by measuring the fraction of aerosol (0.05% 99mTc-tagged human albumin solution) retrieved from the reservoir. Before aerosol recovery experiments, electrostatic fields in the reservoir were measured. Aerosol recovery varied significantly with wall thickness of the reservoir and presence of an antistatic coating (range 6.0-70.3%). A close inverse relationship was found between the mean electrostatic field in the reservoir and aerosol recovery. The nebulized provocative concentration of histamine causing a 20% fall in forced expiratory volume in one second in asthmatics was found to be approximately half that of a standard method when compared with the reservoir system (mean ratio 2.24 (95% confidence interval, 1.60-3.12)). Recovery from an aerosol delivery system with a relatively large collapsible aerosol reservoir was highly dependent on the electrostatic field in the reservoir. In these systems the use of electrostatic field dissipative material for the reservoir is therefore recommended.
Washing plastic spacers in household detergent reduces electrostatic charge and greatly improves delivery
Authors: Pierart F , Wildhaber JH , Vrancken I , Devadason SG , Le Souef PN
Published: September 2002

Ionic detergents reduce electrostatic charge on plastic spacers, thereby improving in vitro drug delivery. The aim of this study was to gain practical information on the use of detergents and to evaluate the relevance of this information on in vivo drug deposition. Measurement of electrostatic charge and salbutamol particle size distribution was carried out on detergent-coated and noncoated plastic spacers. The efficiency of four household detergents was compared, and the influence of dilution and the duration of the antistatic effect were studied. In addition, the level of radiolabelled salbutamol deposition in the lungs of eight healthy adults was compared after inhalation through a new versus a detergent-coated spacer. In vitro, all tested detergents reduced the electrostatic charge on the spacer surface. This resulted in a mean increase of 37.4% (range 33.5-41.2) in small particle (<6.8 microm) salbutamol output compared with water-rinsed/drip-dried spacers. Dilution had no influence on the results and the effect lasted for at least four weeks. In vivo, the mean lung deposition of radiolabelled salbutamol in healthy subjects was 45.6% (range 43.4-49.5) through a detergent-coated spacer compared to 11.5% (range 7.6-17.9) through a static spacer (p<0.001). In conclusion, household detergents offer a simple and practical solution to the problem of static on plastic spacers and significantly improve both in vitro and in vivo delivery of salbutamol.
Influence of gas density on simulated snoring
Authors: Liistro G , Veriter C , Stanescu D
Published: September 2002

According to a recent theoretical model, snoring is related to instability of the upper airway (UA). Factors promoting UA instability include increased gas density. The aim of this study was to test the influence of gas density on simulated snoring production and supraglottic resistance. Supraglottic pressure and flow rate (V') were measured in 10 healthy seated subjects during simulated snoring. Subjects breathed three different gas mixtures: Helium-oxygen, He 79%-O2 21% (He-O2); air; and sulphur hexafluoride-oxygen, F6S 79%-O2 21% (F6S-O2) administered in a random order. Supraglottic resistance (Rsg) was measured on its linear range during quiet breathing and V' was measured at the onset and middle of snoring. Linear Rsg increased and V' conversely decreased with gas density. These data are in agreement with predictions of a mathematical model of the upper airway showing that snoring occurs at lower flow rates when gas density is increased.
Hyperuricaemia in patients with right or left heart failure
Authors: Hoeper MM , Hohlfeld JM , Fabel H
Published: September 2002

Based on the clinical observation that patients with right or left heart failure often present with hyperuricaemia, the relation between serum urate values and haemodynamic variables was studied in patients with primary pulmonary hypertension (PPH) as well as in patients with advanced ischaemic heart disease or dilated cardiomyopathy. The study was a retrospective analysis of 39 patients with PPH and 36 patients with left heart disease, examining serum urate levels in association with haemodynamic variables. Elevated urate concentrations were found in 79% of the PPH patients. There was no association between serum urate levels and mean pulmonary artery pressures, but a significant correlation was found between urate levels and the cardiac index (r=0.48; p=0.0021) and an even stronger correlation between serum urate levels and mean right atrial pressures (r=0.83; p<0.0001). A similar association was found in a subgroup of 21 PPH patients not receiving diuretics. In 36 patients with ischaemic heart disease or dilated cardiomyopathy, hyperuricaemia was present in 78% and was significantly associated with elevated right atrial pressures (r=0.40; p=0.031) and even more so with elevated left atrial pressures (r=0.55; p=0.0005) but not with the cardiac index (r=0.034; p=0.86). The data show that hyperuricaemia in patients with cardiac dysfunction is closely related to elevated right or left atrial filling pressures.
Physiological basis of improvement after lung volume reduction surgery for severe emphysema: where are we?
Authors: Marchand E , Gayan-Ramirez G , De Leyn P , Decramer M
Published: September 2002

Lung volume reduction surgery has become an accepted therapeutic option to relieve the symptoms of selected patients with severe emphysema. In a majority of these patients, it causes objective as well as subjective functional improvement. A proper understanding of the physiological determinants underlying these beneficial effects appears very important in order to better select patients for the procedure that is currently largely carried out on an empirical basis. Lung volume reduction surgery has two distinct effects. Firstly, it causes an increased elastic recoil, which at least partially explains the enhanced maximal expiratory flow. Secondly, it is associated with a reduction of hyperinflation which allows for an increase in global inspiratory muscle strength and in diaphragmatic contribution to tidal volume as well as a decrease in the inspiratory elastic load imposed by the chest wall. Taken together, these effects result in a reduced work of breathing and in an enhanced maximal ventilation which both contribute to the increased exercise capacity and reduced dyspnoea after surgery. The improved lung recoil and the reduced hyperinflation after volume reduction surgery were the primary postulates upon which the usual selection criteria for the procedure were based. It is now likely that these are correct. Nevertheless, some patients do not benefit from lung volume reduction surgery and the current literature does not allow for a refinement of the selection process from a physiological point of view. The exact mechanisms underlying the improvement in lung recoil, lung mechanics, and respiratory muscle function remain incompletely understood. Moreover, the effects of lung volume reduction surgery on gas exchange and pulmonary haemodynamics still need to be more fully investigated. An analysis of the characteristics of patients who do not benefit from the procedure and the development of an animal model for lung volume reduction surgery would probably help address these important issues.
Haemoptysis after breath-hold diving
Authors: Boussuges A , Pinet C , Thomas P , Bergmann E , Sainty JM , Vervloet D
Published: September 2002

Pulmonary oedema has been described in swimmers and self-contained underwater breathing apparatus (Scuba) divers. This study reports three cases of haemoptysis secondary to alveolar haemorrhage in breath-hold divers. Contributory factors, such as haemodynamic modifications secondary to immersion, cold exposure, exercise and exposure to an increase in ambient pressure, could explain this type of accident. Furthermore, these divers had taken aspirin, which may have aggravated the bleeding.
Diaphragmatic paralysis due to Lyme disease
Authors: Faul JL , Ruoss S , Doyle RL , Kao PN
Published: September 2002

Lyme disease is a tick-borne spirochaete infection which, in a proportion of patients, can lead to neuropathy. This article describes a case of diaphragmatic paralysis due to Lyme disease. A 39-yr-old male presented to the hospital because of an acute left facial palsy. Six weeks prior to admission he had developed a circular rash on his left flank during a camping holiday. He also complained of shortness of breath and arthralgia for 1 week. His chest radiograph demonstrated a raised right hemi-diaphragm. Diaphragmatic paralysis was confirmed by fluoroscopy (a positive sniff test). Serology revealed evidence of recent infection by Borrelia burgdorferi. On the basis of the patient's clinical presentation, a recent history of erythema migrans, and positive Lyme serology, a diagnosis of neuroborreliosis was made. He received oral doxycycline therapy (200 mg x day(-1)) for three weeks. Facial and diaphragmatic palsies resolved within eight weeks. On the basis of this case, a diagnosis of Lyme disease should be considered in patients from endemic regions with otherwise unexplained phrenic nerve palsy.
Necrotizing sarcoid granulomatosis in a 14-yr-old female
Authors: Tauber E , Wojnarowski C , Horcher E , Dekan G , Frischer T
Published: September 2002

A case of a 14-yr-old female with necrotizing sarcoid granulomatosis (NSG) is presented. She was referred because of chest pain and malaise, and radiography revealed multiple pulmonary nodules. Her history showed seasonal sensitization to aeroallergens and hay fever. Infectious agents or malignancies did not characterize these nodules. However, she was treated with macrolide antibiotics because of suspected infection with Chlamydia pneumoniae. Open lung biopsy showed histological findings of NSG, with epithelioid granulomatous inflammation, including giant cells, and vasculitis. No further treatment was performed, and symptoms disappeared within a few weeks. The chest radiograph showed gradual improvement. The aetiology of NSG is poorly understood, and is postulated to represent either sarcoidosis or rare forms of pulmonary vasculitis such as Wegener's granulomatosis or the Churg-Strauss syndrome. In the case presented, a coincidence of infection with Chlamydia pneumoniae suggests an involvement of infectious agents in the pattern of formation of immune complexes in the aetiology of NSG.
Estimating the difficulty of oral proficiency tasks: what does the test-taker have to offer?
Authors: Elder Catherine , Iwashita Noriko , McNamara Tim
Published: September 2002

This study investigates the impact of performance conditions on perceptions of task difficulty in a test of spoken language, in light of the cognitive complexity framework proposed by Skehan (1998). Candidates performed a series of narrative tasks whose characteristics, and the conditions under which they were performed, were manipulated, and the impact of these on task performance was analysed. Test-takers recorded their perceptions of the relative difficulty of each task and their attitudes to them. Results offered little support for Skehan’s framework in the context of oral proficiency assessment, and also raise doubts about post hoc estimates of task difficulty by test-takers.
Exploring task difficulty in ESL listening assessment
Authors: Brindley Geoff , Slatyer Helen
Published: September 2002

This article reports on an exploratory study that investigated the comparability of listening assessment tasks used to assess and report learning outcomes of adult ESL learners in Australia. The study focused on the effects of task characteristics and task conditions on learners’ performance in competency-based listening assessment tasks that require learners to demonstrate specific listening behaviours. Key variables investigated included the nature of the input and the response mode. Quantitative and qualitative analyses of test scores suggest that speech rate and item format influence task and item difficulty. However, the complexity of the interaction between text, item and response makes it difficult to isolate the effects of specific variables. Implications of these findings for assessment task validity and reliability are considered and practical consequences for assessment task design in outcomes-based systems are discussed.
Examinee abilities and task difficulty in task-based second language performance assessment
Authors: Norris John M. , Brown James D. , Hudson Thom D. , Bonk William
Published: September 2002

This article summarizes findings from investigations into the development and use of a prototype English language task-based performance test. Data included performances by 90 examinees on 13 complex and skills-integrativetasks, a priori estimations of examinee proficiency differences, a priori estimations of task difficulty based on cognitive processing demands, performance ratings according to task-specific as well as holistic scales and criteria, and examinee self-ratings. Findings indicated that the task-based test could inform intended inferences about examinees’ abilities to accomplish specific tasks as well as inferences about examinees’ likely abilities with a domain of tasks. Although a relationship between task difficulty estimates and examinee performances was observed, these estimates were not found to provide a trustworthy basis for inferring examinees’ likely abilities with other tasks. These findings, as well as study limitations, are further discussed in light of the intended uses for performance assessment within language education, and recommendations are made for needed research into the interaction between task features, cognitive processing and language performance.
The role of task and task-based assessment in a content-oriented collegiate foreign language curriculum
Authors: Byrnes Heidi
Published: September 2002

This article explores the role of task and task-based assessment in a collegiate foreign language (FL) department that shifted its entire undergraduate curriculum from a form-based normative approach to a language-use and language-meaning orientationfor instruction. It examines how the demands for specificity that characterize task-based assessment contributed significantly to an enhanced knowledge base and a new educational culture on the part of practitioners, faculty and graduate students, primarily in literary cultural studies. Deeper insights were obtained not only in terms of assessment but also with regard to the relationship between (1) curriculum, instruction and learning goals and (2) outcomes in such an adult FL program and, ultimately, with regard to possibilities for an expansive interpretation of the notion of task itself.
A computerized task-based test of second language Dutch for vocational training purposes
Authors: van den Branden Kris , Depauw Veerle , Gysen Sara
Published: September 2002

This article describes the development of a task-based test, Taaltoets Instroom Beroepsopleiding (TIBO), designed to measure whether nonnative adult speakers of Dutch possess the level of Dutch language proficiency that is minimally required to enter vocational training in the industrial sector. The test aims to measure functional language proficiency in a direct way, i.e., by presenting examinees with language tasks that they are likely to encounter in vocational training or on the shop floor. The tasks are presented to examinees via a computer program in which sounds, pictures and images are integrated. The article focuses on the three tensions that had to be taken into account throughout the process of test development:

• the tension between the need for a task-based test and the need to efficiently administer the test via a computerized platform;

• the tension between an examinee population that has little training and the potential bias in testing complex abilities via computer;

• the tension between various intended uses for test outcomes and the types of interpretations that may best be informed by the test.
Some reflections on task-based language performance assessment
Authors: Bachman Lyle F.
Published: September 2002

The complexities of task-based language performance assessment (TBLPA) are leading language testers to reconsider many of the fundamental issues about what we want to assess, how we go about it and what sorts of evidence we need to provide in order to justify the ways in which we use our assessments. One claim of TBLPA is that such assessments can be used to make predictions about performance on future language use tasks outside the test itself. I argue that there are several problems with supporting such predictions. These problems are related to task selection, generalizability and extrapolation. Because of the complexity and diversity of tasks in most ‘real-life’ domains, the evidence of content relevance and representativeness that is required to support the use of test scores for prediction is extremely difficult to provide.

A more general problem is the way in which difficulty is conceptualized, both in the way tasks are described and in current measurement models. The conceptualization of ‘difficulty features’ confounds task characteristics with test-takers’ language ability and introduces a hypothetical ‘difficulty’ factor as a determinant of test performance. In current measurement models, ‘difficulty’ is essentially an artifact of test performance, and not a characteristic of assessment tasks themselves. Because of these problems, current approaches to using task characteristics alone to predict difficulty are unlikely to yield consistent or meaningful results. As a way forward, a number of suggestions are provided for both language testing research and practice.
Design and analysis in task-based language assessment
Authors: Mislevy Robert J. , Steinberg Linda S. , Almond Russell G.
Published: September 2002

In task-based language assessment (TBLA) language use is observed in settings that are more realistic and complex than in discrete skills assessments, and which typically require the integration of topical, social and/or pragmatic knowledge along with knowledge of the formal elements of language. But designing an assessment is not accomplished simply by determining the settings in which performance will be observed. TBLA raises questions of just how to design complex tasks, evaluate students’ performances and draw valid conclusions therefrom. This article examines these challenges from the perspective of ‘evidence-centred assessment design’. The main building blocks are student, evidence and task models, with tasks to be administered in accordance with an assembly model. We describe these models, show how they are linked and assembled to frame an assessment argument and illustrate points with examples from task-based language assessment.
Why is ‘is’ easier than ‘-s’?: acquisition of tense/agreement morphology by child second language learners of English
Authors: Ionin Tania , Wexler Kenneth
Published: September 2002

This study of first-language (L1) Russian children acquiring English as a second language (L2) investigates the reasons behind omission of verbal inflection in L2 acquisition and argues for presence of functional categories in L2 grammar. Analyses of spontaneous production data show that the child L2 learners ( n = 20), while omitting inflection, almost never produce incorrect tense/agreement morphology. Furthermore, the L2 learners use suppletive inflection at a significantly higher rate than affixal inflection, and overgenerate be auxiliary forms in utterances lacking progressive participles (e.g., they are help people). A grammaticality judgement task of English tense/agreement morphology similarly shows that the child L2 English learners are significantly more sensitive to the be paradigm than to inflection on thematic verbs. These findings suggest that Tense is present in the learners’ L2 grammar, and that it is instantiated through forms of the be auxiliary. It is argued that omission of inflection is due to problems with the realization of surface morphology, rather than to feature impairment, in accordance with the Missing Surface Inflection Hypothesis of Prévost and White (2000). It is furthermore suggested that L2 learners initially associate morphological agreement with verb-raising and, thus, acquire forms of be before inflectional morphology on in situ thematic verbs.