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Aims: The kinetics of recovery‐period oxygen uptake (VO2) are affected by the O2 deficit generated during exercise. However, studies using ramp tests (RTs) and constant work rate tests (CT) have differently characterized VO2 responses to increased exercise intensity differently. We used these two types of loading patterns to investigate the effects of low‐intensity, medium‐intensity, and high‐intensity exercises on the half time (T1/2) of recovery‐period VO2 and the mechanism. Methods and results: Ten healthy men aged 21.2 ± 0.9 years underwent symptom‐limited cardiopulmonary exercise tests with the ramp protocol to determine their anaerobic threshold. All subjects subsequently underwent three submaximal RT and CT at low, moderate, and high intensities. In all RTs, subjects began exercise by warming up (20 W). In CT, T1/2 was significantly lengthened as exercise intensity increased (CT‐low: 34.0 ± 3.9 s, CT‐moderate: 39.5 ± 3.5 s, CT‐high:44.6 ± 4.2 s; P < 0.01, ANOVA), whereas no significant change was observed in RT, which began with the same work rate (RT‐low: 46.0 ± 5.7 s, RT‐moderate: 45.7 ± 4.8 s, RT‐high: 44.6 ± 3.5 s, RT‐max: 44.8 ± 3.2 s; P = 0.868, ANOVA). Only high‐intensity exercise resulted in two components (the fast and slow components) of VO2 decay, reflecting the increased O2 deficit by anaerobic metabolism. Conclusions: The exercise intensity at the beginning of an exercise affects early recovery‐period VO2, which is a fast component. The T1/2 of recovery‐period VO2 occurs during the fast component, and an increase in O2 deficit affects both the fast and slow components, lengthening the T1/2. The T1/2 of recovery‐period VO2 in CT at moderate or high intensities, even if not symptom limited, can be used to evaluate exercise intolerance and early occurrence of anaerobic metabolism. Submaximal exercise tests may be considered as convenient methods for evaluating exercise tolerance in patients with cardiac failure. [ABSTRACT FROM AUTHOR]

Introduction Asthma-COPD overlap syndrome (ACOS) is the widely recognized syndrome of asthma and COPD coexisting together. Cigarette smoking is a known risk factor for ACOS and is reported to be associated with interstitial lung diseases (ILDs). Subclinical ILDs have been frequently detected in smokers' lungs by radiological and pathological examinations. This finding raises the possibility that unrecognized mild interstitial changes take place in lungs with ACOS. Objectives We sought to determine whether interstitial changes were present in the lungs of patients with ACOS and to characterize the clinical features of ACOS with interstitial changes. Methods Thirty patients with ACOS were enrolled in the study (26 men and 4 women, mean age 70.1 years). Interstitial changes in the lungs were estimated by high-resolution computed tomography (HRCT). Clinical findings and airway wall thickness on HRCT were assessed retrospectively and compared between ACOS patients with and without interstitial changes. Results Interstitial changes were found in seven patients (23.3%) with ACOS who had HRCT. The age and smoking amount were significantly higher in ACOS with interstitial changes than in ACOS without interstitial changes. ACOS with interstitial changes tended to have a higher rate of fungal sensitisation. Multivariate analysis showed pack-years were significantly related to the presence of interstitial changes. Airway walls assessed by HRCT were significantly thicker in ACOS with interstitial changes than in ACOS without interstitial changes. Conclusions The ACOS patients with interstitial changes were heavier smokers and had thicker airway walls on HRCT compared to the ACOS patients without interstitial changes. [ABSTRACT FROM AUTHOR]

Fragmin/protamine microparticles (F/P MPs) have been used as a cell carrier for adipose-derived stromal cells (IR-ASCs) in inbred male Fisher 344 rats, and for preservation and controlled-release of fibroblast growth factor (FGF)-2 and various cytokines in inbred rat plasma (IRP)-DMEM (Dulbecco's modified Eagle's medium) gel. In this study, we investigated the capability of an IRP-DMEM gel containing F/P MPs and/or FGF-2, as a three-dimensional (3D)-culture, to expand IR-ASCs. We found that IR-ASCs grow faster under 3D-culture conditions in low IRP (3%)-DMEM gel containing F/P MPs and FGF-2 without any animal serum than those under 2D-culture in low inbred rat serum (3%)-DMEM with F/P MPs and FGF-2. About 0.3 mL of IR-ASCs (about 4,000,000 cells mL−1) grown in IRP (6%)-DMEM gel containing F/P MPs and FGF-2 disappeared 8 days after subcutaneous injection in rats, suggesting that they are rapidly biodegradable. The number of large (diameter ≥200 μm or containing ≥100 erythrocytes), medium (diameter = 20-200 μm or containing 10-100 erythrocytes) and small (diameter ≤20 μm or containing 1-10 erythrocytes) capillaries after injection with IR-ASCs in an IRP-DMEM gel containing both F/P MPs and FGF-2, as well as the thickness of tissue granulation per microphotograph at the injected site, was significantly higher than those after injection with IR-ASCs in an IRP-DMEM gel containing either FGF-2 or F/P MPs. Thus, IRP-DMEM gel containing F/P MPs and FGF-2 are useful and safe IR-ASC carriers that facilitate cell proliferation, vascularization, and tissue granulation locally at injection sites. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013. [ABSTRACT FROM AUTHOR]

Background. The patients with polymyositis (PM) and dermatomyositis (DM) often develop the malignancies in their clinical course.The incidence of cancer is estimated at about 15%. The risk of cancer is the highest within the first year of myositis diagnosis and drops substantially thereafter. The patients with lung cancer diagnosed more than 5 years after the onset of PM or DM are the minority. Methods and Patients. We surveyed the medical records of patients with lung cancer over the period from 1995 to 2011. Results. We found five patients who developed lung cancer more than 5 years after the diagnosis of PM/DM. Three patients were male, and two were female. The median age was 61.2 (±11.7). Histological types were diverse.The clinical stages ranged from IA to IV. Three patients had smoking histories. Four patients suffered from DM, and one suffered from PM. All patients received oral corticosteroid therapy. Two patients also received ciclosporin, and another two received azathioprine. Anti-Jo-1 antibody was positive in one patient. Four patients were complicated with interstitial pneumonia (IP). Conclusion.These lung cancers diagnosed more than 5 years after the onset of PM/DM were probably related to IP or smoking but might not be comorbid with PM/DM. [ABSTRACT FROM AUTHOR]

Summary Respiratory viral infections are frequently associated with exacerbations of asthma. Double-stranded RNA (dsRNA) produced during viral infections may be one of the stimuli for exacerbation. We aimed to assess the potential effect of dsRNA on certain aspects of chronic asthma through the administration of polyinosine-polycytidylic acid (poly I:C), synthetic dsRNA, to a rat model of asthma. Brown Norway rats were sensitized to ovalbumin and challenged three times to evoke airway remodelling. The effect of poly I:C on the ovalbumin-induced airway inflammation and structural changes was assessed from bronchoalveolar lavage fluid and histological findings. The expression of cytokines and chemokines was evaluated by real-time quantitative reverse transcription PCR and ELISA. Ovalbumin-challenged animals showed an increased number of total cells and eosinophils in bronchoalveolar lavage fluid compared with PBS-challenged controls. Ovalbumin-challenged animals treated with poly I:C showed an increased number of total cells and neutrophils in bronchoalveolar lavage fluid compared with those without poly I:C treatment. Ovalbumin-challenged animals showed goblet cell hyperplasia, increased airway smooth muscle mass, and proliferation of both airway epithelial cells and airway smooth muscle cells. Treatment with poly I:C enhanced these structural changes. Among the cytokines and chemokines examined, the expression of interleukins 12 and 17 and of transforming growth factor-β1 in ovalbumin-challenged animals treated with poly I:C was significantly increased compared with those of the other groups. Double-stranded RNA enhanced airway inflammation and remodelling in a rat model of bronchial asthma. These observations suggest that viral infections may promote airway remodelling. [ABSTRACT FROM AUTHOR]