Cardiopulmonary exercise testing (CPET) in pulmonary emphysema.

In patients affected by chronic obstructive pulmonary disease (COPD), cardiopulmonary response to exercise was never related to the severity of emphysema (E) measured by high resolution computed tomography (HRCT). Sixteen patients (age=65±8 yrs; FEV(1)=54±18%pred; RV=160±28%pred) with moderate to severe E (quantified by lung HRCT as % voxels <-910 HU) were exercised on a cycle-ergometer to exhaustion. Oxygen uptake (V˙(O2)), carbon dioxide output (V˙(CO2)), ventilation (V˙(E)), tidal volume (V(T)), and end-tidal P(CO2) (PET(CO2)) derived variables were measured breath-by-breath.

Effect of heliox on heart rate kinetics and dynamic hyperinflation during high-intensity exercise in COPD.

Respiratory mechanical abnormalities in patients with chronic obstructive pulmonary disease (COPD) may impair cardiodynamic responses and slow down heart rate (HR) kinetics compared with normal resulting in reduced convective oxygen delivery during exercise. We reasoned that heliox breathing (79% helium-21% oxygen) and the attendant reduction of operating lung volumes should accelerate HR kinetics in the transition from rest to high-intensity exercise. Eleven male ambulatory patients with clinically stable COPD undertook constant work-rate cycle testing at 80% of each individuals' maximum work capacity while breathing room air (RA) or heliox (HX), randomly.

Analyses of T cell phenotype and function reveal an altered T cell homeostasis in systemic sclerosis. Correlations with disease severity and phenotypes.

We investigated in systemic sclerosis (SSc) patients the T cell homeostasis and its relationship with the clinical course of the disease. Distribution of peripheral T cell subsets, thymic output, lymphocyte proliferation and apoptosis were analyzed by flow cytometry or ELISA. Age inappropriate levels of naive CD4(+) T cells and thymic output were observed.

Effect of heliox on lung dynamic hyperinflation, dyspnea, and exercise endurance capacity in COPD patients.

We tested the hypothesis that heliox breathing, by reducing lung dynamic hyperinflation (DH) and dyspnea (Dys) sensation, may significantly improve exercise endurance capacity in patients with chronic obstructive pulmonary disease [n = 12, forced expiratory volume in 1 s = 1.15 (SD 0.32) liters].