Impact d'un exercice intense sur les marqueurs cardiaques et de stess oxydant lors de la course à pieds

in 4ème Congrès commun SFMS & SFTS (2011, September)

Introduction : Le risque d’évènements cardiaques ou de mort subite après effort physique intense a été décrit dans diverses études. Chez les personnes ne pratiquant pas régulièrement une activité physique ... [more ▼]

Introduction : Le risque d’évènements cardiaques ou de mort subite après effort physique intense a été décrit dans diverses études. Chez les personnes ne pratiquant pas régulièrement une activité physique, l’incidence de décès liée à un exercice physique est plus importante que chez les jeunes sportifs. Ces évènements indésirables se produisent chez des sujets présentant une maladie coronarienne qui leur était inconnue. L’American Heart Association recommande de réaliser un screening cardiovasculaire pour les athlètes de tout âge. Le but de notre étude était de doser des marqueurs cardiaques très sensibles chez des sujets sédentaires soumis à une course à pieds. Méthodes : Nous avons enrôlés 15 sujets sédentaires (<2heures de sport/ semaine) masculins (22.5±2.15ans) dans notre étude. Du sang EDTA et hépariné a été prélevé juste avant la course (T1), juste après (T2), 3 heures après (T3) et 24 heures après la fin de la course (T4). L’exercice consistait en une course d’une heure sur un tapis roulant à 75% de la VO2max. Un test à l’effort a été préalablement réalisé chez chaque participant deux semaines avant le test d’endurance. Des dosages de marqueurs cardiaques tels que la troponine untrasensible (hsTnT), le peptide natriurétique de type B (NT-proBNP), la myéloperoxydase (MPO) et des marqueurs du stress oxydant tels que le glutathion réduit (GSH), le glutathion oxydé (GOX) et les peroxydes lipidiques ont été dosés. Résultats : Après la course, le NT-proBNP, hsTnT, POXL et MPO augmentent durant les 3 heures qui suivent. Le NT-proBNP a augmenté de façon significative de T2 à T4 comparé au T1. Soixante-dix pourcent des sujets dépassent les valeurs de référence pour la hsTnT au T3 et ce, de façon statistiquement significative comparé aux autres temps. La MPO augment légèrement au T2 mais non significativement. Les peroxydes lipidiques montrent une augmentation au T4 mais non significative. Le GOX augmente de façon significative au T2. Il n’y pas de variation du GSH alors que le rapport GSH/GOX est significativement augmenté au T4. Conclusions : Cette étude a permis de mettre en évidence que ce type d’exercice chez des sujets sédentaires produit un stress oxydant quantifiable et continu durant les 24 heures qui suivent l’effort. Nous n’observons pas d’adaptations antixydantes. L’augmentation des marqueurs cardiaques reflètent l’existence d’un stress cardiaque liée à cet exercice. [less ▲]

Hypophosphatémie et ostéomalacie oncogénique

in Revue Médicale Suisse (2011), 7

In this article, we will discuss about hypophosphatemia due to tumor-induced osteomalacia. This disease is characterized by severe muscular and articular tenderness inducing profound walking limitation ... [more ▼]

In this article, we will discuss about hypophosphatemia due to tumor-induced osteomalacia. This disease is characterized by severe muscular and articular tenderness inducing profound walking limitation. Clinical chemistry results show severe hypophosphatemia due to hyperphosphaturia. Fibroblast growth factor 23 (FGG-23) is abnormally high. Physiological role of FGF-23 is examined. We also consider the pathophysiology of tumor induced osteomalacia, the use of different investigations to localize the tumor and therapies available to treat this rare disease. [less ▲]

Current opinion on tendinopathy

in Journal of Sports Science & Medicine [=JSSM] (2011), 10(2), 238-253

Tendinopathy is characterized by pain in the tendon and impaired performance sometimes associated with swelling of the tendon. Its diagnosis is usually clinical but ultrasonography and magnetic resonance ... [more ▼]

Tendinopathy is characterized by pain in the tendon and impaired performance sometimes associated with swelling of the tendon. Its diagnosis is usually clinical but ultrasonography and magnetic resonance imaging can refine the diagnosis. Tendinopathy is highly prevalent and is one of the most frequently self reported musculoskeletal diseases in physical workers and sports people. Nevertheless, it is very difficult to carry out general epidemiologic studies on tendinopathy because of the varying sports cultures and sports habits in different countries. The aetiology of tendinopathy seems to be multi-factorial, involving intrinsic and extrinsic factors. The role of inflammation is still debated but the absence of inflammatory cells does not mean that inflammatory mediators are not implicated. Different theories have been advanced to explain pain and chronicity mechanisms, but these mechanisms remain largely unknown. “Conventional” treatments are generally employed empirically to fight pain and inflammation but they do not modify the histological structure of the tendon. However, these treatments are not completely satisfactory and the recurrence of symptoms is common. Currently, eccentric training remains the treatment of choice for tendinopathy, even though some studies are contradictory. Moreover, many interesting new treatments are now being developed to treat tendinopathy, but there is little evidence to support their use in clinical practice. [less ▲]

Evaluation of the use of VEGF111 for the treatment of tendon lesions.

Poster (2011, May 20)

Alterations of tendons are common pathologies resulting from repetitive or abnormal mechanical sollicitations. Very frequently lesions become chronic and may even lead to rupture. As there is no current ... [more ▼]

Alterations of tendons are common pathologies resulting from repetitive or abnormal mechanical sollicitations. Very frequently lesions become chronic and may even lead to rupture. As there is no current efficient treatment for curing this type of diseases, new therapeutic approaches are being tested and developed. Injection of platelet-rich plasma (PRP) seems to be a promising treatment by local release of growth factors. Among these factors, VEGF-A is known to induce positive effects on vascular functions and angiogenesis, and could be implicated in the healing process of tendons. Several isoforms of VEGF-A have been described in literature, including VEGF165 and 121. VEGF111 is encoded by exons 1-4 and 8a. The lack of exon 5 enables VEGF111 to resist to proteolytic degradation and the absence of exons 6 and 7 reduces its affinity for several macromolecules present on the cell surface and in the extracellular matrix. In vivo, it has been shown to be highly proangiogenic and diffusible. A 5mm defect was surgically performed in the Achilles tendon of 60 rats. Two hours after closure of the fascia and the skin, an injection within the wound was performed with PBS alone (n=30) or with PBS containing 100 ng of VEGF111 (n=30). 10 rats of each group were sacrificed at days 5, 15 and 30. The operated tendon was then carefully removed and collected for either immunohistochemical analyses or mechanical testing. At each time point, the section and the overall appearance of the repairing tendons were similar for PBS and VEGF111-injected tendon. As compared to controls, injection of VEGF111 seemed to promote a faster angiogenesis, although the number of samples was at this stage too low for performing reliable statistical analysis. Mechanical resistance to rupture of the repairing tendons was also measured. No difference between the two groups was observed after 5 or 15 days. By contrast, increased tensile strength was clearly evidenced in the VEGF-treated group after 30 days. These preliminary data seem to indicate a positive effect of a single VEGF111 injection for restoring the mechanical properties of tendons after their section. Additional experiments are planned for confirmation purposes and for further characterizing the model. It includes a “dose- response” analysis, the use of VEGF165 as an additional control and a study evaluating the effect of several injections. [less ▲]

Use of a novel high-sensitivity troponin T, I and MPO, NT-proBNP assays to detect myocardial injury in patients with atrial fibrillation treated by direct-current cardioversion

in Clinical Chemistry & Laboratory Medicine (2011, May), 49(Special Suppl), 312

Fatty acids and cardiovascular risk

in Clinical Chemistry & Laboratory Medicine (2011, May), 49(Special Suppl), 313

Fatty acids determinations: an cardiovascular risk? Preliminary results

in Biomedica - Life Science Summit (2011, April 07)

Analyse critique des traitements conservateurs des tendinopathies

in Julia, Marc; Hirt, Daniel; Croisier, Jean-Louis (Eds.) et al Tendon et jonction tendino-musculaire (2011)

Quels critères de retour au sport après tendinopathie ?

in Julia, M.; Hirt, D.; Croisier, Jean-Louis (Eds.) et al Tendon et jonction tendino-musculaire - De la biomécanique aux applications thérapeutiques (2011)

Prévention des lésions tendineuses : mythe ou réalité ?

in Julia, M.; Hirt, D.; Croisier, Jean-Louis (Eds.) et al Tendon et jonction tendino-musculaire - De la biomécanique aux applications thérapeutiques (2011)