Severe loss of mechanical efficiency in COVID‐19 patients

Background: There is limited information about the impact of coronavirus disease (COVID-19) on the muscular dysfunction, despite the generalized weakness and fatigue that patients report after overcoming the acute phase of the infection. This study aimed to detect impaired muscle efficiency by evaluating delta efficiency (DE) in patients with COVID-19 compared with subjects with chronic obstructive pulmonary disease (COPD), ischaemic heart disease (IHD), and control group (CG). Methods: A total of 60 participants were assigned to four experimental groups: COVID-19, COPD, IHD, and CG (n = 15 each group). Incremental exercise tests in a cycle ergometer were performed to obtain peak oxygen uptake (VO2 peak). DE was obtained from the end of the first workload to the power output where the respiratory exchange ratio was 1. Results: A lower DE was detected in patients with COVID-19 and COPD compared with those in CG (P ≤ 0.033). However, no significant differences were observed among the experimental groups with diseases (P > 0.05). Lower VO2 peak, peak ventilation, peak power output, and total exercise time were observed in the groups with diseases than in the CG (P < 0.05). A higher VO2 , ventilation, and power output were detected in the CG compared with those in the groups with diseases at the first and second ventilatory threshold (P < 0.05). A higher power output was detected in the IHD group compared with those in the COVID-19 and COPD groups (P < 0.05) at the first and second ventilatory thresholds and when the respiratory exchange ratio was 1. A significant correlation (P < 0.001) was found between the VO2 peak and DE and between the peak power output and DE (P < 0.001). Conclusions: Patients with COVID-19 showed marked mechanical inefficiency similar to that observed in COPD and IHD patients. Patients with COVID-19 and COPD showed a significant decrease in power output compared to IHD during pedalling despite having similar response in VO2 at each intensity. Resistance training should be considered during the early phase of rehabilitation

Pilot study for the production of Arthrospira (Spirulina) maxima in the Azores.

11th International Conference on Applied Phycology”. Galway, Irlanda, 21-27 de Junho de 2008

Dysfonction des cordes vocales chez le sportif : intérêt du reconditionnement à l’effort

International audienc

Resistance to TGF beta in SV40 large T-immortalized rat intestinal epithelial cells is associated with down-regulation of TGF beta type I receptor

A new continuous cell line designated ESKI-1 was established by transfection of rat fetal intestinal epithelial cells with ecotropic retroviruses containing SV40 large T oncogene. The ESKI-1 cell line exhibits morphologic features of an epithelial cell line and expresses the OCI-5 and cytokeratin 8 transcripts associated with epithelial cells in the small intestine. Signal transduction and proliferation responses to TGF beta has been characterized in ESKI-1 cells, in comparison with the spontaneously-immortalized IEC cell lines originating from neonatal rat duodenum and ileum. ESKI-1 express both TGF alpha and TGF beta. However, despite a marked increase in TGF beta-stimulated p78 kinase activity observed in ESKI-1 and IEC cells, TGF beta did not modulate growth, or extracellular matrix expression in ESKI-1 cells. Resistance to growth modulation was associated with downregulation of TGF beta. Type I receptor expression in the SV40 large T-immortalized cells. Thus, proliferative resistance to TGF beta inhibition can result from depletion of the TGF beta type I receptor and disruption of the TGF beta signaling pathway downstream the p78 serine/threonine kinase. These molecular defects constitute two early events during the SV40LT-mediated immortalization and neoplastic progression of the intestinal epithelia

Évaluation de la toxicité musculaire de la chimiothérapie lors d’une épreuve fonctionnelle à l'exercice

International audienc

The six-minute stepper test is related to muscle strength but cannot substitute for the one repetition maximum to prescribe strength training in patients with COPD

Tristan Bonnevie,1,2 Mathilde Allingham,3 Guillaume Prieur,1,4 Yann Combret,5,6 David Debeaumont,7 Maxime Patout,1,8 Antoine Cuvelier,1,8 Catherine Viacroze,8 Jean-Fran&ccedil;ois Muir,1,2,8 Clement Medrinal,1,4 Francis-Edouard Gravier1,2 1Normandie University, UNIROUEN, UPRES EA 3830, Rouen University Hospital, Haute Normandie Research and Biomedical Innovation, Rouen, France; 2ADIR Association, Rouen University Hospital, Rouen, France; 3Rouen University Hospital, School of Physiotherapy, Rouen, France; 4Intensive Care Unit Department, Le Havre Hospital, H&ocirc;pital Jacques Monod, Montivilliers, France; 5Institute of Experimental and Clinical Research (IREC), Pole of Pulmonology, ORL and Dermatology, Catholic University of Louvain, Brussels, Belgium; 6Physiotherapy Department, Le Havre Hospital, Le Havre, France; 7Department of Respiratory and Exercise Physiology and CIC-CRB 1404, Rouen University Hospital, Rouen, France; 8Pulmonary, Thoracic Oncology and Respiratory Intensive Care Department, Rouen University Hospital, Rouen, France Purpose: There are many barriers to pulmonary rehabilitation, including a limited access to evaluation centers. To cope with these difficulties, field tests are often used to prescribe endurance training. As field tests are related to muscle strength, they could also be used to prescribe strength training and increase the access to pulmonary rehabilitation in rural area. However, their validity for this purpose has never been studied.Patients and methods: The relationship between the 6-minute stepper test (6MST), 6-minute walk test, maximal workload achieved during cardiopulmonary exercise testing (Wpeak), and one repetition maximum (1RM) was assessed in 35 patients with COPD through a retrospective chart review to derive predictive equation of the 1RM from these tests. The effectiveness of these equations to prescribe strength training at 70% of the 1RM was assessed in an independent cross-validation group of 34 patients with COPD.Results: There was a moderate relationship between the 6MST, Wpeak and the 1RM (r=0.44 and r=0.41, respectively, both P&le;0.01). Whatever the test, the prescription of strength training using the estimated 1RM compared with the measured 1RM resulted in a mean absolute difference and a mean bias of about 30 kg.Conclusion: The use of the 6MST and Wpeak for the prescription of strength training would result in a clinically not acceptable error. Therefore, they should not be used as a substitute for the 1RM to prescribe strength training. Keywords: six-minute stepper test, strength training, COPD, pulmonary rehabilitation &nbsp

A specific prediction equation is necessary to estimate peak oxygen uptake in obese patients with metabolic syndrome

International audiencePurposeThe aims were to: (1) compare peak oxygen uptake (V˙O2peak) predicted from four standard equations to actual V˙O2peak measured from a cardiopulmonary exercise test (CPET) in obese patients with metabolic syndrome (MetS), and (2) develop a new equation to accurately estimate V˙O2peak in obese women with MetS.MethodsSeventy-five obese patients with MetS performed a CPET. Anthropometric data were also collected for each participant. V˙O2peak was predicted from four prediction equations (from Riddle et al., Hansen et al., Wasserman et al. or Gläser et al.) and then compared with the actual V˙O2peak measured during the CPET. The accuracy of the predictions was determined with the Bland–Altman method. When accuracy was low, a new prediction equation including anthropometric variables was proposed.ResultsV˙O2peak predicted from the equation of Wasserman et al. was not significantly different from actual V˙O2peak in women. Moreover, a significant correlation was found between the predicted and actual values (p < 0.001, r = 0.69). In men, no significant difference was noted between actual V˙O2peak and V˙O2peak predicted from the prediction equation of Gläser et al., and these two values were also correlated (p = 0.03, r = 0.44). However, the LoA95% was wide, whatever the prediction equation or gender. Regression analysis suggested a new prediction equation derived from age and height for obese women with MetS.ConclusionsThe methods of Wasserman et al. and Gläser et al. are valid to predict V˙O2peak in obese women and men with MetS, respectively. However, the accuracy of the predictions was low for both methods. Consequently, a new prediction equation including age and height was developed for obese women with MetS. However, new prediction equation remains to develop in obese men with MetS