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Background Cigarette smoking is the main cause of chronic obstructive pulmonary disease (COPD) inducing oxidative stress and local tissue injury, resulting in pulmonary inflammation. Advanced glycation end products (AGEs) are produced by glycation and oxidation processes and their formation is accelerated in inflammatory conditions. In this study we assessed whether AGE accumulation in the skin is elevated in COPD and associates with disease severity. Methods 202 mild-to-very-severe COPD patients and 83 old (40-75 years) and 110 young (18-40 years) healthy smokers and never-smokers were included. AGEs were measured by skin autofluorescence (SAF). Demographic variables, smoking habits, co-morbidities and lung function values were obtained. Results COPD patients (FEV1 = 55% predicted) had significantly higher SAF values than old and young healthy controls: 2.5 vs. 1.8 and 1.2 (arbitrary units, p < 0.05). No differences in SAF values were found between GOLD stages I-IV (2.4, 2.3, 2.5, 2.5 respectively). Lower function (FEV1/FVC, MEF50/FVC, RV/TLC) and higher number of packyears were significantly associated with SAF (p < 0.05). Conclusions SAF is increased in mild-to-very severe COPD patients compared with healthy controls. Interestingly, SAF was not associated with disease severity as values were comparable between different GOLD stages (stage I-IV) of COPD. This may suggest that AGEs play a role in the induction phase of COPD in susceptible smokers. Future studies should further investigate the mechanisms underlying AGEs formation and accumulation in COPD. [ABSTRACT FROM AUTHOR]

Summary: Background: Inhaled glucocorticosteroids reduce airway inflammation in asthma patients, thereby improving lung function and reducing airway hyperresponsiveness and symptoms. The response to glucocorticosteroids can be measured with the glucocorticosteroid skin-blanching test. We investigated if asthmatics have a lower skin-blanching response to glucocorticosteroids than non-asthmatic subjects and if asthmatics with airway obstruction have lower skin-blanching response than those without obstruction. Finally, we assessed which clinical and inflammatory parameters influence the variability in skin-blanching response. Methods: We evaluated the skin-blanching response to topical budesonide in a large group of 315 well-characterized asthmatics and their relatives (asthma n = 114, healthy n = 140, other = 61) Results: The skin-blanching scores of the asthma probands and their healthy spouses were not significantly different. The skin-blanching score of patients with FEV1 < 80% predicted was lower than of patients without obstruction. Lower skin-blanching score was significantly associated with lower FEV1 %predicted, higher age, female gender, absence of allergy and summer season, but not with use of inhaled or oral glucocorticosteroids or packyears smoking. Conclusions: Asthmatics do not have lower skin-blanching response to glucocorticosteroids than healthy subjects. Furthermore, lower skin-blanching response to glucocorticosteroids is associated with lower FEV1, female gender, higher age and the absence of allergy. [ABSTRACT FROM AUTHOR]

The management of bronchiolitis obliterans syndrome (BOS) after hematopoietic cell transplantation presents many challenges, both diagnostically and therapeutically. We developed a computed tomography (CT) voxel-wise methodology termed parametric response mapping (PRM) that quantifies normal parenchyma, functional small airway disease (PRM fSAD ), emphysema, and parenchymal disease as relative lung volumes. We now investigate the use of PRM as an imaging biomarker in the diagnosis of BOS. PRM was applied to CT data from 4 patient cohorts: acute infection (n = 11), BOS at onset (n = 34), BOS plus infection (n = 9), and age-matched, nontransplant control subjects (n = 23). Pulmonary function tests and bronchoalveolar lavage were used for group classification. Mean values for PRM fSAD were significantly greater in patients with BOS (38% ± 2%) when compared with those with infection alone (17% ± 4%, P < .0001) and age-matched control subjects (8.4% ± 1%, P < .0001). Patients with BOS had similar PRM fSAD profiles, whether a concurrent infection was present or not. An optimal cut-point for PRM fSAD of 28% of the total lung volume was identified, with values >28% highly indicative of BOS occurrence. PRM may provide a major advance in our ability to identify the small airway obstruction that characterizes BOS, even in the presence of concurrent infection. [ABSTRACT FROM AUTHOR]