Central nucleus quantification.

<p><b>A</b>) Cryosections were analyzed by labeling nuclei (blue) and laminin (red). Immuno-detection is shown for 10 µm skeletal muscle cryosections. The number of central nuclei (white arrows) is expressed over 100 fibres and reported as a ratio. Ratio are calculated from 9 COPD and MTCSA >70 cm², 7 COPD and MTCSA <70 cm² and 7 healthy subjects. <b>B</b>) The total numbers of central nuclei were quantified per 100 fibres for patients with COPD and MTCSA >70 cm², patients with COPD and MTCSA <70 cm² and for healthy subjects. Nucleus inside the perimeter of a given fibre delimited by laminin was counted as a central nucleus, expressed over 100 fibres and reported as a ratio. Distinct letter represents a statistically significant difference (ANOVA; p<0.05).</p

Telomere length.

<p><b>A</b>) Minimal, <b>B</b>) Mean and <b>C</b>) Maximal telomere restriction fragment length of the <i>vastus lateralis</i> plotted in healthy subjects (n = 7), patients with COPD and MTCSA >70 cm²) (n = 9) and patients with COPD and MTCSA <70 cm² (n = 7). The solid horizontal line represents the mean value for the group. Distinct letter represents a statistically significant difference (ANCOVA; p<0.05).</p

Minimal, mean and maximum telomere length correlation with MTCSA.

<p><b>A</b>) Relationship between minimal telomere length and Mid-thigh Cross-Sectional Area (MTCSA) in patients with COPD and healthy controls. Telomere length significantly correlated with MTCSA in the studied population (r = 0.523; p = 0.005). <b>B</b>) Relationship between mean telomere length and Mid-thigh Cross-Sectional Area (MTCSA) in patients with COPD and healthy controls. Telomere length significantly correlated with MTCSA in the studied population (r = 0.435; p = 0.019). <b>C</b>) Relationship between maximum telomere length and Mid-thigh Cross-Sectional Area (MTCSA) in patients with COPD and healthy controls. Telomere length significantly correlated with MTCSA in the studied population (r = 0.491; p = 0.009).</p

Satellite cells quantification.

<p><b>A</b>) <i>Vastus lateralis</i> muscle cryosections were labeled for co-expression and localization of nuclear Paired box transcription factor 7 (green), DAPI (blue) and laminin (red). Cells positive for pax7 or NCAM (not shown) and DAPI located between the plasmalemma and the basal lamina were counted as satellite cells (white arrow). The number of satellite cells is expressed over 100 fibres and reported as a ratio. Ratio are calculated from 9 COPD and MTCSA >70 cm², 7 COPD and MTCSA <70 cm² and 7 healthy subjects. <b>B</b>) The numbers of nuclei having a positive label for Pax7 (white) and NCAM (black) were counted as satellite cells. Cells positive for pax7 or NCAM and DAPI located between the plasmalemma and the basal lamina were counted as satellite cells. The number of satellite cells is expressed over 100 fibres and reported as a ratio; ANOVA; p>0.05.</p

Subjects characteristics

<p>Definition of abbreviations: BMI = Body mass index; FEV₁ = Forced expiratory volume in 1 second; FVC = Forced vital capacity; DLCO = Diffusing capacity of carbon monoxide; MTCSA = Mid-thigh cross-sectional area; CSA = Cross-sectional area. Values with different lower case letter are significantly different (p<0.05).</p>*<p>p<0.001;</p>†<p>p<0.01.</p