Biomedical subjects
J H Dijkman
Publications and source records attributed to J H Dijkman.
[Open lung biopsy in seriously ill patients with undiagnosed lung infiltrates].
Explore the source record for details and available documents.
A randomized clinical trial of alpha(1)-antitrypsin augmentation therapy.
We have investigated whether restoration of the balance between neutrophil elastase and its inhibitor, alpha(1)-antitrypsin, can prevent the progression of pulmonary emphysema in patients with alpha(1)-antitrypsin deficiency. Twenty-six Danish and 30 Dutch ex-smokers with alpha(1)-antitrypsin deficiency of PI*ZZ phenotype and moderate emphysema (FEV(1) between 30% and 80% of predicted) participated in a double-blind trial of alpha(1)-antitrypsin augmentation therapy. The patients were randomized to either alpha(1)-antitrypsin (250 mg/kg) or albumin (625 mg/kg) infusions at 4-wk intervals for at least 3 yr. Self-administered spirometry performed every morning and evening at home showed no significant difference in decline of FEV(1) between treatment and placebo. Each year, the degree of emphysema was quantified by the 15th percentile point of the lung density histogram derived from computed tomography (CT). The loss of lung tissue measured by CT (mean +/- SEM) was 2.6 +/- 0.41 g/L/yr for placebo as compared with 1.5 +/- 0.41 g/L/yr for alpha(1)-antitrypsin infusion (p = 0.07). Power analysis showed that this protective effect would be significant in a similar trial with 130 patients. This is in contrast to calculations based on annual decline of FEV(1) showing that 550 patients would be needed to show a 50% reduction of annual decline. We conclude that lung density measurements by CT may facilitate future randomized clinical trials of investigational drugs for a disease in which little progress in therapy has been made in the past 30 yr.
Cigarette smoking and pulmonary diffusion defects in rheumatoid arthritis.
The pathogenesis of lung disease in rheumatoid arthritis (RA) has still to be defined. Risk factors associated with lung involvement in RA were investigated by means of pulmonary function studies in 40 RA patients without apparent lung disease. A decreased carbon monoxide (CO) diffusion capacity indicative of interstitial lung disease (ILD) was the main pulmonary function defect found in the first 20 patients. The occurrence was associated with current cigarette smoking. This association was confirmed in a case control study performed subsequently. These data suggest that ILD in RA is stimulated by smoking and provide an additional argument that modification of smoking behaviour in RA patients might lead to less severe complications.
Ozone-induced airway hyperresponsiveness in patients with asthma: role of neutrophil-derived serine proteinases.
Proteinase inhibitors may be of potential therapeutic value in the treatment of respiratory diseases such as chronic obstructive pulmonary disease (COPD) or asthma. Our aim was to study the role of neutrophils, and neutrophil-derived serine proteinases in an acute model in patients with asthma. Exposure to ozone induces an acute neutrophilic inflammatory reaction accompanied by an increase in airway hyperresponsiveness. It is thought that these two effects of ozone are linked, and that neutrophil-derived serine proteinases (i.e. elastase) may play a role in the ozone-induced airway hyperresponsiveness. Therefore, we examined the effect of recombinant antileukoprotease (rALP), one of the major serine proteinase inhibitors in the lung, on ozone-induced changes in airway hyperresponsiveness in this model. We observed that 16 h after exposure to ozone, airway hyperresponsiveness to methacholine was increased both following placebo and rALP treatment. There was no significant difference between placebo and rALP treatment (change in area under the dose-response curve to methacholine: 117.3+/-59.0 vs 193.6+/-59.6 % fall x DD; p=.12). Moreover, the immediate decrease in FEV1 after ozone exposure was not significantly different between the two groups (placebo: -29.6+/-6.7%; rALP: -20.9+/-3.8%; p=.11). In addition, no significant differences were observed in plasma levels of fibrinogen degradation products generated by neutrophil serine proteinases before and after exposure to ozone. We conclude that neutrophil-derived serine proteinases are not important mediators for ozone-induced hyperresponsiveness.
[Laboratory testing virtually centralized to benefit both patients and drug research].
Laboratory analyses in multicentre safety studies of new drugs usually are performed in central laboratories outside the Netherlands. Patient care requires local (hospital) laboratory tests. In the so-called Virtually Centralized Laboratory the Dutch local laboratories report their results after data communication and data transformation in such a way that they seem to form one laboratory. The local analytical results are transformed by calibrating the local methods using standard preparations, thus reducing the inter laboratory variation. This concept may lead to one set of national reference values for all general clinical chemical and haematological laboratory tests.
Effect of neutrophil serine proteinases and defensins on lung epithelial cells: modulation of cytotoxicity and IL-8 production.
Neutrophil accumulation in the lung may contribute to tissue injury as observed in inflammatory diseases. Both oxidative and non-oxidative mechanisms are involved in neutrophil-mediated tissue injury. Non-oxidative mechanisms include the release of neutrophil granule proteins such as the serine proteinases elastase and cathepsin G, and the non-enzymatic defensins. Because stimulated neutrophils are thought to release their products simultaneously, we investigated possible interactions between purified defensins and serine proteinases with respect to induction of cellular injury and their ability to induce interleukin-8 (IL-8) synthesis in cells of the lung epithelial cell line A549. Whereas defensins induced cell lysis, elastase and cathepsin G induced detachment of A549 cells. Co-incubation of elastase and cathepsin G revealed an additive effect on detachment, whereas defensins inhibited serine proteinase-induced detachment. Vice versa, both serine proteinases reduced defensin-induced cell lysis. Furthermore, elastase and cathepsin G prevented defensin-induced IL-8 synthesis. In contrast, no inhibitory interaction between cathepsin G and defensins was observed with respect to their antibacterial activity. The results from this study indicate that, at sites of inflammation, neutrophil-mediated injury might be regulated by interactions between released defensins and serine proteinases.
The development of the 'Quality-of-life for Respiratory Illness Questionnaire (QOL-RIQ)': a disease-specific quality-of-life questionnaire for patients with mild to moderate chronic non-specific lung disease.
Chronic non-specific lung disease (CNSLD) encompasses asthma as well as chronic obstructive pulmonary disease (COPD). Recently in health care, there has been increasing awareness in the functional, psychological and social aspects of the health of patients; their quality of life (QOL). Quality-of-life research addressing CNSLD patients has been rather underdeveloped for a long period of time. Recently, however, the importance of QOL is being increasingly recognized, and several research groups have started to study QOL in CNSLD patients in more detail. This paper describes the construction of a disease-specific QOL instrument for patients with mild to moderately severe CNSLD. Items relating to several domains of QOL were listed, and 171 CNSLD patients in general practice were asked how much of a problem each item had been (assessed on a seven-point Likert scale). After applying an item-selection procedure, a uni-dimensional QOL questionnaire was constructed consisting of 55 items divided into seven domain subscales: breathing problems, physical problems, emotions, situations triggering or enhancing breathing problems, general activities, daily and domestic activities, and social activities, relationships and sexuality. Reliability estimates of the domain subscales of the constructed questionnaire varied from 0.68 to 0.89, and was 0.92 for the QOL for Respiratory Illness Questionnaire (QOL-RIQ) total scale. A first impression of the construct validity of the questionnaire was gained by investigation of the relationship between the QOL domain subscales and several indicators of illness severity, as well as the relative contribution of illness severity variables, background characteristics and symptoms to QOL, using regression analysis. Further research to validate the questionnaire to a greater extent (construct validity, test-retest reliability and responsiveness to change) is currently taking place.
Effect of defensins on interleukin-8 synthesis in airway epithelial cells.
Neutrophils play an important role in inflammatory processes in the lung and may cause tissue injury through, for example, release of proteinases such as neutrophil elastase. In addition to neutrophil elastase, stimulated neutrophils also release small nonenzymatic and cationic polypeptides termed defensins. The aim of the present study was to investigate whether defensins induce interleukin (IL)-8 expression in cells of the A549 lung epithelial cell line and in human primary bronchial epithelial cells (PBEC). Supernatants of defensin-treated A549 cells contained increased neutrophil chemotactic activity (16-fold) that was inhibited by antibodies against IL-8. Concurrently, within 3 and 6 h, defensins significantly increased the IL-8 levels in supernatants of both A549 cells (n = 6, P < 0.05 and P < 0.01, respectively) and PBEC (n = 4, P < 0.001 and P < 0.001, respectively). This defensin-induced increase was fully inhibited by the serine proteinase inhibitor alpha 1-proteinase inhibitor. In addition, defensins also increased IL-8 mRNA levels (12-fold); this increase was dependent on de novo mRNA synthesis and did not require protein synthesis. Furthermore, defensins did not affect IL-8 mRNA stability, indicating that the enhanced IL-8 expression was due to increased transcription. Our findings suggest that defensins, released by stimulated neutrophils, stimulate IL-8 synthesis by airway epithelial cells and thus may mediate the recruitment of additional neutrophils into the airways.
Relationship between loss in parenchymal elastic recoil pressure and maximal airway narrowing in subjects with alpha1-antitrypsin deficiency.
Airway hyperresponsiveness is characterized by an increase in sensitivity and excessive airway narrowing to inhaled bronchoconstrictor stimuli. There is experimental evidence that maximal airway narrowing is related to lung elasticity in normal and asthmatic subjects. We hypothesized that reduced lung elasticity by parenchymal destruction increases the level of maximal airway narrowing in subjects with alpha1-antitrypsin deficiency. To that end, we measured complete dose-response curves to methacholine, quasistatic pressure-volume (P-V) curves, diffusion capacity for carbon monoxide per unit lung volume (DLCO/VA), and mean lung density by spirometrically controlled computed tomography (CT) scan in eight non- or ex-smoking subjects with alpha1-antitrypsin deficiency. Methacholine dose-response curves were expressed as the provocative concentration causing 20% fall in FEV1 (PC20). A maximal response plateau was considered if > or = 3 highest doses fell within a 5% response range, the maximal response (MFEV1) being the average value on the plateau. The P-V curves were characterized by an index of compliance (exponent K), and elastic recoil pressures at 90, and 100% of TLC (PL90 and PLmax). In all subjects a complete dose-response curve to methacholine could be recorded. MFEV1 was significantly correlated with logPC20 (r = -0.94, p < 0.001), but not with baseline FEV1 (r = -0.53, p > 0.15). There was a significant relationship between MFEV1 and PL90 (r = -0.79, p < 0.02), PLmax (r = -0.87, p < 0.005), and K (r = 0.79, p < 0.02). Furthermore MFEV1 was significantly correlated with DLCO/VA (r = -0.76, p < 0.03) and with lung density (r = 0.78, p < 0.04). We conclude that in subjects with alpha1-antitrypsin deficiency the level of maximal airway narrowing increases with loss in lung elasticity, with reduction in diffusing capacity, and with lowered mean lung density. This suggests that loss in elastic recoil pressure secondary to parenchymal destruction contributes to excessive airway narrowing in humans in vivo.
The alveolar type II cell is a pluripotential stem cell in the genesis of human adenocarcinomas and squamous cell carcinomas.
Studies in a canine bronchogenic carcinoma model indicate that alveolar type II cells may differentiate from carcinogen-exposed epithelium of larger bronchi and generate adenocarcinomas with bronchioloalveolar and other growth patterns. In this study, we investigated whether type II cells are one of the major proliferating cells (= stem cells) in the genesis of two major subsets of bronchogenic carcinoma in humans. Adenocarcinomas (17 bronchioloalveolar; 3 papillary; and 10 other) and squamous cell carcinomas (n = 27) as well as (pre)neoplastic lesions in adjacent bronchi and bronchioles were examined for the presence of type II cell markers and cellular proliferation markers (PCNA; Ki-67) using light and electron microscopy and immunohistochemistry. Distinctive features of type II cells, which do not depend upon the degree of cell maturity, are the approximately cuboid shape, large and roundish nucleus, cytoplasmic staining for surfactant protein A (SP-A), and presence of multilamellar bodies or their precursory forms. Cells with this phenotype were found in early progressive (i.e., dysplastic, in situ, microinvasive) lesions in conducting airways and in all the carcinomas investigated, although with a much greater abundance among glandular lesions compared to squamous lesions. The most consistent sites of type II cells were the basal and adjacent epithelial layers. Nuclear PCNA (Ki-67) expression usually predominated in the same region. None of the lesions displayed specific Clara cell features. Our findings strongly suggest that the type II cell is a pluripotential stem cell in human lung carcinogenesis. Based on our findings in humans and dogs, we postulate that type II tumor stem cells may originate from one of two sources: (1) normal bronchial epithelium (by an oncofetal mechanism of differentiation); and (2) normal alveolar type II cells.
Stereological methods: a new approach in the assessment of pulmonary emphysema.
In order to develop a reliable and sensitive method for studying the development and progression of pulmonary emphysema, we compared stereological indices with the usual index for grade of emphysema, i.e., the mean linear intercept (Lm), in elastase-induced emphysema in mice. The Lm and stereological indices, including volumes of total lung tissue (V(lt)), airspaces (V(air)), and surface area of alveolar walls (S(alv)), were determined in 5-microns, H&E-stained, paraffin-embedded lung sections from elastase- (n = 7) or saline-treated (n = 8) mice. The indices were measured by point counting, using Cavalieri's principle (V(lt)) and V(air)) or by counting intersections of alveolar walls with test lines of a known length (S(alv) and Lm). Elastase treatment resulted in a significant increase of Lm and of V(air), both indicating airspace enlargement, and in a significant decrease of V(lt) and S(alv), indicating destruction of alveolar walls. Between each of the stereological indices and the Lm, significant correlations were found when all lungs were included, but not when the emphysematous lungs were considered separately. We conclude that stereological methods can be powerful morphometric tools for studying pulmonary emphysema development and progression, since they give information not only about the grade of airspace enlargement but also about the grade of destruction of alveolar walls. Based on this unique property, stereological methods also allow a distinction between pulmonary emphysema and unrelated conditions with dilatation of airspaces only.
Alveolar stem cells in canine bronchial carcinogenesis.
Alveolar type II cells are not present in normal epithelium of canine segmental bronchi but after carcinogen exposure they do occur in intra-epithelial lesions with all degrees of atypia and in invasive lesions with different glandular growth patterns. Immunohistochemistry for proliferation markers (PCNA; Ki-67) strongly suggest that such novel type II cells are pluripotential stem cells in canine bronchial carcinogenesis. Very likely, bronchial carcinogenesis is subject to an oncofetal mechanism of differentiation: bronchial epithelial retrodifferentiation followed by novel differentiation of alveolar tumor stem cells.
The prognostic value of NCAM, p53 and cyclin D1 in resected non-small cell lung cancer.
Expression of the neural cell adhesion molecule, NCAM, in frozen sections has been associated with decreased postoperative survival in non-small cell lung carcinoma. Of the various isoforms of NCAM described, the highly sialylated isoform plays a role in the migration of embryonal cells from the neural crest and is expressed by highly malignant tumours such as small cell lung carcinomas. We investigated the clinical significance of expression of this NCAM isoform as a prognostic factor in a series of 96 non-small cell lung carcinomas resected with curative intent. We also evaluated the effect of microwave pre-treatment of formalin-fixed, paraffin-embedded sections on the NCAM immunostaining and related the outcome to the postoperative clinical course of disease. In addition, in an attempt to extend our search for possible molecular markers of unfavourable prognosis in lung cancer, we evaluated increased immunostaining for p53 and cyclin D1 in the same series. We did not find a significant relation between expression of NCAM or its highly sialylated isoform and the length of postoperative survival. The numbers of positive cases (9 and 14, respectively) were relatively low. Increased p53 and cyclin D1 immunostaining (50 and 55 of the 96 tumours) failed to show a significant relation with postoperative survival. In our material, tumour stage was the only significant prognostic factor.
Complications in the use of the subcutaneous tunnelled intratracheal oxygen catheter.
Transtracheal oxygen delivery seems to be a safe procedure in the treatment of chronic obstructive pulmonary disease (COPD) with chronic hypoxaemia. Even so, serious complications do occur. Three patients in whom we used a subcutaneous tunnelled intratracheal oxygen catheter (ITO2C) are described. Surgical intervention was required in all because of complications from the procedure. One of the complications--tracheal and catheter obstruction with stridor and subcutaneous emphysema by granulomatous tissue--has to our knowledge not been reported before.
Prognostic factors in resected non-small cell lung cancer: an immunohistochemical study of 39 cases.
Non-small cell lung carcinoma (NSCLC) is a histologically heterogeneous collection of tumours with variable clinical behaviour. Performance status, tumour stage and histological type have important prognostic implications, but the clinical outcome in an individual patient remains unpredictable. In search of other prognostic factors we studied the expression of several immunohistochemical markers in NSCLC, resected with curative intent. Tumour samples of 19 patients with a postoperative disease-free survival of at least 5 years and those of 20 patients who died of tumour recurrence within 2 years after resection were selected for this study. The populations were matched for age, sex and tumour stage. We investigated the expression of markers for neuroendocrine differentiation, cell adhesion and cell cycle regulation in both populations. None of the investigated immunohistochemical markers distinguished between long- and short-term survivors of resected NSCLC. In stage 1 tumours expression of embryonal NCAM was observed more often in the short survival group (P = 0.026) and in stage 3a EGF-r expression was associated with the long survival group (P = 0.047). However, these findings remained to be confirmed. Expression of Rb, NCAM and embryonal NCAM was not detected in adenocarcinomas, whereas T-Ag and chromogranin A immunoreactivity was absent from squamous cell carcinomas.
Interstitial lung disease with pleural effusion caused by simvastin.
Simvastin, a HMG-CoA reductase blocker, is used for the treatment of certain forms of hypercholesterolaemia. Simvastin is prescribed to lower high serum levels of cholesterol by inhibiting a specific enzyme, hydroxy-methylglutarylCo-enzym-A (HMG-CoA) reductase. This ultimately leads to an increase of the number of LDL-receptors in the liver, and thus, to a decrease of the serum LDL-cholesterol. To a much lesser extent it lowers the serum VLDL-cholesterol and makes the serum HDL-cholesterol level rise. In general, this relatively new compound is well tolerated and only a few, mostly minor, adverse effects have been reported so far. We present a patient who developed interstitial lung disease with pleural effusion most probably as a result of the use of Simvastin.
Assessment of the progression of emphysema by quantitative analysis of spirometrically gated computed tomography images.
RATIONALE AND OBJECTIVES: The authors assessed the progression of pulmonary emphysema by means of quantitative analysis of computed tomography images. METHODS: Twenty-three patients suffering from emphysema due to an alpha 1-antitrypsin deficiency, aged 45 +/- 7 years and exsmokers, were scanned twice with a 1-year time interval. At 90% of the vital lung capacity, slices with a thickness of 1.5 mm were acquired at the level of the carina and 5 cm above the carina; slices with a thickness of 1 cm were acquired 5 cm below the carina. The entire lung was scanned spirally at a respiratory status, corresponding with 75% of the total lung capacity at baseline. The mean lung densities (MLD) were calculated in an objective manner with new analytic software featuring automated detection of the lung contours. RESULTS: Mean lung densities decreased by 14.2 +/- 12.0 Hounsfield units (HU; P < 0.001) above the carina, by 18.1 +/- 14.4 HU (P < 0.001) at the carina level, by 23.6 +/- 15.0 HU (P < 0.001) below the carina, and by 12.8 +/- 22.2 HU (P < 0.01) for the entire lung. The decrease in MLD was most obvious in the lower lung lobes. For the same patient group, the annual decrease in the forced expiratory volume (FEV1) and the carbon monoxide-diffusion were 120 +/- 190 mL (P < 0.01) and 10 +/- 70 mmol/kg/minute ( P < 0.2), respectively. No significant correlation was found between the decrease in MLD and the decrease in FEV1. CONCLUSIONS: Progression of emphysema can be assessed in an objective manner based on the mean lung density (MLD), measured from computed tomography volume scans as well as from single-slice scans. Mean lung density has proved to be more sensitive than FEV1 and carbon monoxide-diffusion.