Related Articles

Relationship between daily physical activity and exercise capacity in patients with COPD.

Respir Med. 2012 Oct 18;

Authors: Zwerink M, van der Palen J, van der Valk P, Brusse-Keizer M, Effing T

Abstract
BACKGROUND: Exercise training programmes for patients with COPD are effective in improving exercise capacity. The few trials that have investigated the effects of exercise programmes on daily physical activity show contradictory results. AIM: To investigate the relation between daily physical activity level and exercise capacity in patients with COPD using data of a randomised controlled trial in which the exercise intervention was aimed at improvement of both physical activity and exercise capacity (the COPE-II study). METHODS: These are secondary analyses of the COPE-II study, a randomised controlled trial in which a community-based physiotherapeutic exercise programme was evaluated. Daily physical activity was measured with a pedometer (steps/day). Exercise capacity was measured with an incremental maximal cycle ergometer test, the incremental (ISWT) and endurance shuttle walk test (ESWT). Pearson correlation coefficients were calculated. RESULTS: At baseline, correlations between steps/day and VO(2peak), ISWT (m), ESWT (m) and ESWT (s) were 0.54, 0.59, 0.44, and 0.34, respectively (all p < 0.01). In the intervention group, correlations between change in steps/day over 7 months and change in ISWT (m), ESWT (m) and ESWT (s) were 0.47, 0.41, and 0.38, respectively (all p < 0.01). In the control group, these same correlations were weak to non-existent. CONCLUSIONS: A moderate to weak relationship was found between daily physical activity and exercise capacity. These results strengthen our beliefs that exercise interventions need to target not only exercise capacity but also behaviour change with regard to daily physical activity to achieve improvements in both parameters.

PMID: 23085213 [PubMed - as supplied by publisher]

Role of autophagy in COPD skeletal muscle dysfunction.

J Appl Physiol. 2012 Oct 18;

Authors: Hussain SN, Sandri M

Abstract
Chronic obstructive pulmonary disease (COPD) is a debilitating disease caused by parenchymal damage and irreversible airflow limitation. In addition to lung dysfunction, patients with COPD develop weight loss, malnutrition, poor exercise performance and skeletal muscle atrophy. The latter has been attributed to an imbalance between muscle protein synthesis and protein degradation. Several reports have confirmed that enhanced protein degradation and atrophy of limb muscles of COPD patient is mediated in part through activation of the ubiquitin proteasome pathway and that this activation is triggered by enhanced production of reactive oxygen species. Until recently, the importance of the autophagy-lysosome pathway in protein degradation of skeletal muscles has been largely ignored, however, recent evidence suggest that this pathway is actively involved in recycling of cytosolic proteins, organelles and protein aggregates in normal skeletal muscles. The protective role of autophagy in the regulation of muscle mass has recently been uncovered in mice with muscle-specific suppression of autophagy. These mice develop severe muscle weakness, atrophy and decreased muscle contractility. No information is yet available about the involvement of the autophagy in the regulation of skeletal muscle mass in COPD patients. Pilot experiments on vastus lateralis muscle samples suggest that the autophagy-lysosome system is induced in COPD patients compared to control subjects. In this review, we summarize recent progress related to molecular structure, regulation and roles of the autophagy-lysosome pathway in normal and diseased skeletal muscles. We also speculate about regulation and functional importance of this system in skeletal muscle dysfunction in COPD patients.

PMID: 23085958 [PubMed - as supplied by publisher]

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Can serum procalcitonin levels help interpret indeterminate chest radiographs in patients hospitalized with acute respiratory illness?

J Hosp Med. 2012 Oct 19;

Authors: Walsh EE, Swinburne AJ, Becker KL, Nylen ES, Snider RH, Baran A, Peterson DR, Falsey AR

Abstract
BACKGROUND: Clinical diagnosis of pneumonia is difficult and chest radiographs often indeterminate, leading to incorrect diagnoses and antibiotic overuse. OBJECTIVE: To determine if serum procalcitonin (ProCT) could assist in managing patients with respiratory illness and indeterminate radiographs. DESIGN: Subjects were prospectively enrolled during 2 consecutive winters. SETTING: A 520-bed hospital in Rochester, NY. PATIENTS: Five hundred twenty-eight adults admitted with acute respiratory illness were enrolled. MEASUREMENTS: Serum ProCT, admission diagnoses, and chest radiographic findings were used to derive receiver operating characteristics curves to assess predictive accuracy of ProCT for the presence of infiltrates. RESULTS: Subjects with pneumonia had higher ProCT (median 0.27 ng/ml) than those with exacerbations of chronic obstructive pulmonary disease (0.08 ng/ml), acute bronchitis (0.09 ng/ml), or asthma (0.06 ng/ml). ProCT had moderate accuracy for the presence of infiltrates (area under curve [AUC] 0.72), when indeterminate radiographs were independently classified as infiltrates by a pulmonologist evaluating patients. CONCLUSIONS: ProCT may be useful in diagnosing pneumonia when chest radiographs are indeterminate. Journal of Hospital Medicine 2012; © 2012 Society of Hospital Medicine.

PMID: 23086568 [PubMed - as supplied by publisher]

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Sputum analysis: non-invasive early lung cancer detection.

J Cell Physiol. 2012 Oct 19;

Authors: D'Urso V, Doneddu V, Marchesi I, Collodoro A, Pirina P, Giordano A, Bagella L

Abstract
Lung cancer is the leading cause of cancer-related deaths over the world, characterized by a very high mortality rate. Molecular technique development tries to focus on early detection of cancers by studying molecular alterations that characterize cancer cells. Worldwide lung cancer research has focused on an ever-increasing number of molecular elements of carcinogenesis at genetic, epigenetic and protein levels. The non-invasiveness is the characteristic that all clinical trials on cancer detection should have. Abnormal chest imaging and/or non-specific symptoms are initial signals of lung cancer that appear in an advanced stage of disease. This fact represents the cause of the low 5-year survival rate: over 90% of patients dying within five years of diagnosis. Since smokers have higher quantity of sputum containing exfoliated cells from the bronchial tree, and the sputum represents the most easily accessible biological fluid and its collection is non-invasive, analysis of this sample represents a good area of research in early lung cancer diagnosis. Continued cigarette smoking is the cause of chronic obstructive pulmonary disease (COPD), with an estimated attributable risk factor exceeding 80% in smoking affected individuals. Lung cancer is found in 40% - 70% of patients with COPD, particularly in severe disease, and it is a common cause of death in these patients. A large prospective trial of almost half a million non-smokers showed as lung cancer is also common in patients with COPD who have never smoked. This review describes issues related to early lung cancer screening using non-invasive methods. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc.

PMID: 23086732 [PubMed - as supplied by publisher]