Cholinergic Hyperresponsiveness of Peripheral Lung Parenchyma in Chronic Obstructive Pulmonary Disease.

Respiration. 2011 May 11;

Authors: Lanças T, Kasahara DI, Gross JL, Pires-Neto RC, Deheinzelin D, Mauad T, Negri EM, Dolhnikoff M

Background: Up to 60% of chronic obstructive pulmonary disease (COPD) patients can present airway hyperresponsiveness. However, it is not known whether the peripheral lung tissue also shows an exaggerated response to agonists in COPD. Objectives: To investigate the in vitro mechanical behavior and the structural and inflammatory changes of peripheral lung tissue in COPD patients and compare to nonsmoking controls. Methods: We measured resistance and elastance at baseline and after acetylcholine (ACh) challenge of lung strips obtained from 10 COPD patients and 10 control subjects. We also assessed the alveolar tissue density of neutrophils, eosinophils, macrophages, mast cells and CD8+ and CD4+ cells, as well as the content of α-smooth muscle actin-positive cells and elastic and collagen fibers. We further investigated whether changes in in vitro parenchymal mechanics correlated to structural and inflammatory parameters and to in vivo pulmonary function. Results: Values of resistance after ACh treatment and the percent increase in tissue resistance (%R) were higher in the COPD group (p ≤ 0.03). There was a higher density of macrophages and CD8+ cells (p < 0.05) and a lower elastic content (p = 0.003) in the COPD group. We observed a positive correlation between %R and eosinophil and CD8+ cell density (r = 0.608, p = 0.002, and r = 0.581, p = 0.001, respectively) and a negative correlation between %R and the ratio of forced expiratory volume in 1 s to forced vital capacity (r = -0.451, p < 0.05). Conclusions: The cholinergic responsiveness of parenchymal lung strips is increased in COPD patients and seems to be related to alveolar tissue eosinophilic and CD8 lymphocytic inflammation and to the degree of airway obstruction on the pulmonary function test.

PMID: 21576920 [PubMed - as supplied by publisher]

Is preoperative physiotherapy/pulmonary rehabilitation beneficial in lung resection patients?

Interact Cardiovasc Thorac Surg. 2011 May 17;

Authors: Nagarajan K, Bennett A, Agostini P, Naidu B

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether preoperative physiotherapyypulmonary rehabilitation is beneficial for patients undergoing lung resection. Ten papers were identified using the reported search, of which five represented the best evidence to answer the clinical question. Jones et al. showed in 13 subjects receiving a preoperative rehabilitation programme (PRP) an improvement of maximum oxygen uptake consumption (VO2 max) of an average 2.4 ml/kg/min (95% confidence interval 1-3.8; P=0.002). Bobbio et al. showed in 12 patients with chronic obstructive pulmonary disease (COPD) and VO2 max <15 ml/kg/min that PRP could effect a mean improvement in VO2 max of 2.8 ml/kg/min (P<0.001). Sekine et al. demonstrated a reduced length of hospital stay (21±7 days vs. 29±9 days; P=0.0003) in 22 subjects who underwent PRP for two weeks compared with a historical control of 60 patients with COPD. Varela et al. using a cross-sectional design with historical controls showed that one day of chest physiotherapy comprising inspiratory and peripheral muscle training compared with routine nursing care was associated with a lower atelectasis rate (2% vs. 7.7%) and a median length of stay that was 5.73 days vs. 8.33 days (P<0.0001). Weiner et al. in a prospective randomised controlled study, showed that two weeks of PRP followed by two months of postoperative rehabilitation produced a better predicted postoperative forced expiratory volume in one second in the study group than in the control group at three months (lobectomy +570 ml vs. -70 ml; pneumonectomy +680 ml vs. -110 ml). We conclude that preoperative physiotherapy improves exercise capacity and preserves pulmonary function following surgery. Whether these benefits translate into a reduction in postoperative pulmonary complication is uncertain. Keywords: Lung resection; Preoperative physiotherapy.

PMID: 21586476 [PubMed - as supplied by publisher]

Arguments Against Inhaled Glucocorticoids in COPD by Phenotype Instead of by Severity.

Arch Bronconeumol. 2011 Jun;47(6):269-270

Authors: Rodríguez-Roisin R

PMID: 21592638 [PubMed - as supplied by publisher]

Epigenetic control of gene expression in the lung.

Am J Respir Crit Care Med. 2011 May 15;183(10):1295-301

Authors: Yang IV, Schwartz DA

Epigenetics is traditionally defined as the study of heritable changes in gene expression caused by mechanisms other than changes in the underlying DNA sequence. There are three main classes of epigenetic marks-DNA methylation, modifications of histone tails, and noncoding RNAs-each of which may be influenced by the environment, diet, diseases, and ageing. Importantly, epigenetic marks have been shown to influence immune cell maturation and are associated with the risk of developing various forms of cancer, including lung cancer. Moreover, there is emerging evidence that these epigenetic marks affect gene expression in the lung and are associated with benign lung diseases, such as asthma, chronic obstructive pulmonary disease, and interstitial lung disease. Technological advances have made it feasible to study epigenetic marks in the lung, and it is anticipated that this knowledge will enhance our understanding of the dynamic biology in the lung and lead to the development of novel diagnostic and therapeutic approaches for our patients with lung disease.

PMID: 21596832 [PubMed - in process]