KL-6 levels are elevated in plasma from patients with acute respiratory distress syndrome.

The acute respiratory distress syndrome (ARDS) is an extreme form of lung injury characterised by disruption to the alveolar epithelium. KL-6 is a mucin-like glycoprotein expressed on type II pneumocytes. Circulating levels of KL-6 have diagnostic and prognostic significance in a number of interstitial lung diseases, and when elevated are thought to indicate disruption of the alveolar epithelial lining. In this study, the authors sought to determine whether plasma KL-6 levels were elevated in patients with ARDS and whether these were associated with aetiology, disease severity, outcome or ventilatory strategy. Plasma samples were collected from 28 patients with ARDS, nine ventilated controls of matched illness severity and 10 healthy individuals. KL-6 concentrations were measured by enzyme-linked immunosorbent assay. Patients with ARDS had higher plasma levels of KL-6 (median 537 U x mL(-1), interquartile range (IQR) 383-1,119), as compared to ventilated controls (median 255 U x mL(-1), IQR 83-338) and normal individuals (median 215 U x mL(-1), IQR 149-307). In patients with ARDS, plasma KL-6 levels were higher in nonsurvivors than survivors, and correlated positively with oxygenation index and negatively with arterial oxygen tension:inspiratory oxygen fraction ratio. There were also significant positive correlations with mean and peak airway pressures. Elevated levels of plasma KL-6 may provide a useful marker for acute respiratory distress syndrome in ventilated patients and have possible prognostic significance. Alveolar epithelial cell damage may be influenced by the nature of mechanical ventilatory support.

Pulmonary fibrosis and lung cancer: risk and benefit analysis of pulmonary resection.

OBJECTIVE: Pulmonary fibrosis is associated with an increased risk of lung cancer and outcome of surgical resection in this setting is unknown. METHODS: We studied 22 patients (24 operations) with pulmonary fibrosis and non-small cell lung cancer treated between 1991 and 2000 (study group) and compared outcome with 951 other patients (964 operations) treated for non-small cell lung cancer over the same period (control patients). RESULTS: The two groups did not differ significantly in age (68 vs 65 years), smoking history (86% vs 95% smokers), forced expiratory volume in 1 second (2.5 L/min vs 2.3 L/min) or forced vital capacity (3.2 L vs 3.7 L), but patients with pulmonary fibrosis were more likely to be male (72% vs 58%, P <.05). The operative mortality was higher in patients with pulmonary fibrosis than in control patients (17% vs 3.1%, P <.01) and there was a higher procedure-specific mortality in pulmonary fibrosis for pneumonectomy (33% vs 5.1%, P <.01) and lobectomy (12% vs 2.6%, P <.01). Patients with pulmonary fibrosis had a higher incidence of postoperative lung injury, (21% vs 3.7%, P <.01) and a longer mean hospital stay (17 vs 9 days, P <.05). In patients with pulmonary fibrosis, the actuarial 3-year survival was 54%. There were 11 deaths in the study group, 4 postoperatively (all acute respiratory distress syndrome) and 7 late deaths (metastatic disease, n = 2; progressive pulmonary fibrosis, n = 5). Median follow-up (to death or last review) was 13 months (range, 0-120 months). Five patients developed postoperative acute respiratory distress syndrome and in 4 of these patients this proved to be fatal. Postoperative acute respiratory distress syndrome was associated with lower preoperative total lung carbon monoxide diffusion capacity (median, 58% vs 70%, P =.03) and lower preoperative carbon monoxide diffusion capacity corrected for alveolar volume (median, 48% vs 58%, P =.05) and a higher preoperative composite physiological index (median, 44 vs 33, P =.008). None of the preoperative lung function parameters or operative finding were predictors of late death. CONCLUSION: Patients with pulmonary fibrosis undergoing pulmonary resection for non-small cell lung cancer have increased postoperative morbidity and mortality, but an important subgroup has a good long-term outcome. Postoperative acute respiratory distress syndrome is associated with low preoperative gas transfer and a high composite physiological index. Resection of non-small cell lung cancer is appropriate in pulmonary fibrosis, provided that the level of functional impairment is carefully factored into patient selection.

Cytoplasmic deposition of NFkappaB decoy oligonucleotides is insufficient to inhibit bleomycin-induced pulmonary inflammation.

Lung inflammation leads to severe tissue destruction and ultimately organ failure in a number of diseases, including cystic fibrosis (CF). The transcription factor nuclear factor kappa B (NFkappaB) regulates expression of many pro-inflammatory mediators. We have assessed the effect of topical administration of NFkappaB decoys in a bleomycin model of acute lung inflammation. Using fluorescein-labelled decoy oligonucleotides (ODN) (80 microg/mouse) we have shown that lipid-complexed and 'naked' ODN transfect conducting airway epithelium in a comparable manner (approximately 65% of cells). However, the ODN were detectable in the cytoplasm, but not in the nucleus of transfected cells. An increase of ODN dose to 500 microg/mouse did not increase nuclear transfection significantly. We determined the effect of cytoplasmic NFkappaB decoys on bleomycin-induced inflammation. We transfected mice with 'naked' decoy and scrambled ODN (500 microg) 1 h before intratracheal administration of bleomycin. We measured IL6 secretion in BALF and lung homogenates and total and differential cell counts in BALF 5 days after bleomycin administration. We did not detect a difference between NFkappaB decoy and scrambled ODN-treated animals in any of the parameters tested. We suggest that access of ODN to the nucleus of airway epithelial cells is a key problem, limiting the efficacy of such decoy strategies, as well as attempts at gene repair.

Alveolar macrophages and T cells from sarcoid, but not normal lung, are permissive to adenovirus infection and allow analysis of NF-kappa b-dependent signaling pathways.

Adenovirus (Adv)-mediated gene transfer requires efficient infection of target cells. The objective of this study was to establish whether alveolar macrophages (AM) and T cells (AT) from sarcoid patients were permissive to infection with Adv vectors and if this property could be used to investigate cytokine gene regulation. Sarcoid and normal bronchoalveolar lavage (BAL) specimens infected with Adv vectors expressing either beta-galactosidase or a green fluorescent protein were analyzed for transgene expression by fluorescence-activated cell sorter (FACS) and direct immunofluorescence, respectively. Expression of surface antigens previously associated with Adv infection, the coxsackie/adenovirus receptor (CAR), alpha v beta 3, and alpha v beta 5 integrins, was also assessed using FACS analysis. Sarcoid AM and AT were found to efficiently express Adv transgenes, unlike AM from normal volunteers, peripheral blood monocytes, and peripheral blood T cells. Cells permissive to Adv infection expressed the CAR and alpha v beta 5 integrin (also alpha v beta 3 integrin for AM). The data indicate that the upregulation of Adv receptors and the ability to infect sarcoid AM and AT are related to the inflammatory environment within the lung. Having demonstrated efficient Adv-mediated transgene delivery to sarcoid AM and AT, a construct encoding porcine I kappa B alpha was then used to investigate the requirement for nuclear factor (NF)-kappa B in the regulation of cytokine gene expression in pulmonary sarcoidosis. Overexpression of I kappa B alpha in sarcoid BAL specimens indicated that tumor necrosis factor-alpha and interleukin (IL)-6 production by AM and interferon (IFN)-gamma production by AT is NF-kappa B dependent, whereas IL-4 production by AT is NF-kappa B independent. This is the first occasion that the requirement for NF-kappa B in IFN-gamma gene expression within primary human T cells has been demonstrated. The results of this study have implications for the future investigation of molecular pathways in inflammatory lung disease.

Rapid and effective correction of RF inhomogeneity for high field magnetic resonance imaging.

The well-known variability in the distribution of high frequency electromagnetic fields in the human body causes problems in the analysis of structural information in high field magnetic resonance images. We describe a method of compensating for the purely intensity-based effects. In our simple and rapid correction algorithm, we first use statistical means to determine the background image noise level and the edges of the image features. We next populate all "noise" pixels with the mean signal intensity of the image features. These data are then smoothed by convolution with a gaussian filter using Fourier methods. Finally, the original data that are above the noise level are normalized to the smoothed images, thereby eliminating the lowest spatial frequencies in the final, corrected data. Processing of a 124 slice, 256 x 256 volume dataset requires under 70 sec on a laptop personal computer. Overall, the method is less prone to artifacts from edges or from sensitivity to absolute head position than are other correction techniques. Following intensity correction, the images demonstrated obvious qualitative improvement and, when subjected to automated segmentation tools, the accuracy of segmentation improved, in one example, from 35.3% to 84.7% correct, as compared to a manually-constructed gold standard.

Spatiotopic organization in human superior colliculus observed with fMRI.

Spatiotopy is a fundamental organizing principle of the visual brain. Using functional magnetic resonance imaging, we have demonstrated reliable data, consistent with spatiotopic organization in the human superior colliculi. Five subjects underwent cardiac-triggered echo-planar image acquisition, during which they viewed alternating left and right visual hemifield stimulation. Intensity variations from the variable TR were removed, and the data were evaluated for correlation with the lateralized stimulus. The data indicate a strongly preferential response of the left superior colliculus to the right side of visual space, and vice versa. This is consistent with previous findings in animal systems and confirms the existence of spatiotopy in the human superior colliculus.

Stability, repeatability, and the expression of signal magnitude in functional magnetic resonance imaging.

In 23 fMRI studies on six subjects, we examined activation in visual and motor tasks. We modeled the expected activation time course by convolving a temporal description of the behavioral task with an empirically determined impulse response function. We evaluated the signal activation intensity as both the number of activated voxels over arbitrary correlation thresholds and as the slope of the regression line between our modeled time course and the actual data. Whereas the voxel counting was strikingly unstable (standard deviation 74% in visual trials at a correlation of 0.5), the slope was relatively constant across trials and subjects (standard deviation <14%). Using Monte Carlo methods, we determined that the measured slope was largely independent of the contrast-to-noise ratio. Voxel counting is a poor proxy for activation intensity, with greatly increased scatter, much reduced statistical power, and increased type II error. The data support an alternative approach to functional magnetic resonance imaging (fMRI) that allows for quantitative comparisons of fMRI response magnitudes across trials and laboratories.

Serial circulating adhesion molecule levels reflect disease severity in systemic sclerosis.

Microvascular damage occurs in systemic sclerosis (SSc) and is associated with increased expression of endothelial adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Elevated levels of the soluble circulating forms of these molecules have recently been reported in SSc. We have extended this observation by collecting serial serum samples from 12 patients with systemic sclerosis, at intervals between 4 and 12 months, through the course of their disease (mean period of observation 44 months). Circulating ICAM-1, VCAM-1 and E-selectin were measured by ELISA, and changes in these levels were compared with alterations in disease activity as assessed by skin sclerosis score, serum creatinine, erythrocyte sedimentation rate and pulmonary function tests coincident with each serum sample. The mean levels were ICAM-1 627 ng/ml, VCAM-1 959 ng/ml and E-selectin 81 ng/ml. In 8/12 patients, there was a substantial change in at least one disease parameter during the assessment period. In seven (88%) of these patients, changes in circulating VCAM-1 or E-selectin were associated with disease severity, falling with improvement in renal function or skin score, and rising with deterioration in pulmonary function tests. The maximum recorded level of VCAM-1 (3550 ng/ml) shortly preceded an acute renal SSc crisis. In two cases (25%), the correlation was statistically significant (P < or = 0.01). The ICAM-1 level did not reflect clinical changes in any patients. These results provide further evidence for endothelial cell dysfunction in SSc, and suggest that serial measurements of VCAM-1 and E-selectin may have potential value as surrogate markers for clinical progression or remission in this disease.

Role of thrombin in pulmonary fibrosis.

Pulmonary fibrosis commonly develops in systemic sclerosis. We assessed the role of thrombin in promoting fibroblast proliferation in the lungs in this disorder. Bronchoalveolar lavage fluid (BALF) thrombin concentrations were higher in ten patients with systemic sclerosis than in 12 healthy controls (14.6 vs 3.6 nmol/L, p < 0.02), but values in patients with cryptogenic fibrosing alveolitis (n = 10) or sarcoidosis (n = 10) were not increased. BALF from all patients induced fibroblast proliferation. This proliferation was attenuated by thrombin inhibitors for BALF from systemic sclerosis patients only. We suggest thrombin contributes to lung fibroblast proliferation in this disorder.

Immunohistochemical localization of transforming growth factor-beta 1 in the lungs of patients with systemic sclerosis, cryptogenic fibrosing alveolitis and other lung disorders.

To study the role of transforming growth factor-beta 1 (TGF-beta 1) in the pathogenesis of pulmonary fibrosis we have examined lung biopsies from nine patients with systemic sclerosis and interstitial lung disease, eight with 'lone' cryptogenic fibrosing alveolitis, two with cystic fibrosis, two with extrinsic allergic alveolitis, two with Langerhans' cell histiocytosis, one with lymphangioleiomyomatosis, one with giant cell interstitial pneumonia, and one adenocarcinoma of the lung. In cryptogenic fibrosing alveolitis, both 'lone' and associated with systemic sclerosis alveolar macrophages, bronchial epithelium and hyperplastic type II pneumonocytes expressed intracellular TGF-beta 1. Extracellular TGF-beta 1 was found in the fibrous tissue immediately beneath the bronchial and hyperplastic alveolar epithelium. In normal lung, however, the alveolar epithelium and alveolar interstitium were negative for both forms of TGF-beta 1. There was strong expression of TGF-beta 1 in hyperplastic mesothelium and its underlying connective tissue and in Langerhans' cells in the two cases of histiocytosis. In the organizing pneumonia in cystic fibrosis, the intraalveolar buds of granulation tissue reacted strongly for the extracellular form of TGF-beta 1 and the overlying hyperplastic epithelium expressed the intracellular form. In lymphangioleiomyomatosis, the aberrant smooth muscle cells strongly expressed intracellular TGF-beta 1 and the extracellular form was expressed in the adjacent connective tissue. In giant cell interstitial pneumonia, the numerous alveolar macrophage including the multinucleate forms, expressed intracellular TGF-beta 1, as did the hyperplastic alveolar epithelium.(ABSTRACT TRUNCATED AT 250 WORDS)

Enlarged mediastinal lymph nodes in the fibrosing alveolitis of systemic sclerosis.

The aim of this study was to determine the prevalence of enlarged mediastinal lymph nodes in systemic sclerosis (SSc) and relate this to the extent of pulmonary disease and disease activity as judged by high resolution computed tomography (HRCT). The HRCT scans of 78 patients with SSc were reviewed. The extent of lung disease and HRCT pattern were analysed and CT scans examined on soft tissue window settings for evidence of mediastinal lymph node enlargement. Sixty six (85%) patients had evidence of lung involvement on CT. Enlarged mediastinal lymph nodes were present in 21 (32%) patients with lung involvement but in only 1 (8%) patient without. The prevalence of enlarged mediastinal nodes increased with more extensive lung involvement on CT (p < 0.025), but correlated poorly with the type of CT appearance and concurrent erythrocyte sedimentation rate. Mediastinal lymph node enlargement occurs frequently in patients with SSc, particularly if lung involvement is extensive.

Immunogenetic prediction of pulmonary fibrosis in systemic sclerosis.

75 systemic sclerosis patients were independently tested for pulmonary fibrosis, autoantibodies, and MHC class II genes. 24 of 42 (57%) patients with pulmonary fibrosis had either HLA DR3/DRw52a or anti-Scl-70 vs 2 of 33 (6%) patients without pulmonary fibrosis. The presence of DR3/DRw52a or anti-Scl-70 gives a relative risk of 16.7 for the development of pulmonary fibrosis in a patient with scleroderma--a risk substantial enough to require careful monitoring of these patients and treatment at an early stage of disease.