Cardiopulmonary exercise testing is a better outcome predictor than exercise echocardiography in asymptomatic aortic stenosis.

BACKGROUND: Objective assessment of maximal aerobic capacity using peak oxygen consumption (peak VO2) can be helpful in the management of patients with asymptomatic aortic stenosis (AS). The relationship between peak VO2 and AS severity criteria derived from rest and supine exercise echocardiography (SEE) has never been explored. OBJECTIVES: We aimed to determine whether low peak VO2 (3m/s) and left ventricle ejection fraction>50% prospectively underwent resting and SEE and cardiopulmonary exercise testing (CPX). RESULTS: Peak VO2 was lower than expected (21.9+/-7.4mL/kg/min), i.e. /=85% had a negative predictive value of 97%. CONCLUSION: CPX detects a high proportion of false asymptomatic AS patients with poorer outcome that cannot be predicted by SEE markers of AS severity. Assessment of aerobic capacity should be part of current approach within a "watchful waiting" strategy.Peer reviewe

The role of eosinophils and basophils in allergic diseases considering genetic findings.

International audiencePURPOSE OF REVIEW: Basophils and eosinophils represent less than 1 and 5% of white blood cells, respectively. Their role in asthma and allergic inflammation remains incompletely defined. The present review addresses recent advances regarding the role of these two cell populations in allergic inflammation and asthma regarding both biological and genetic point of view. RECENT FINDINGS: Regarding eosinophils, the role of interleukin(IL)-25, IL-33 and thymic stromal lymphoprotein (TSLP) have been evidenced, and activation states of eosinophil β1 and β2 integrins have been found to correlate with the measurement of eosinophil recruitment and pulmonary function in asthma. New insights into the biology of basophils concern their role as regulators of Th2 cell response through IL-4 expression or the differentiation of monocytes to macrophages, and their population heterogeneity in human. The transcription factor PU.1 was reported to be involved in controlling transcription of specific genes both in eosinophils and basophils. Candidate genetic studies on eosinophils have explored genes involved in the intracellular calcium influx and apoptosis. At the genome-wide level, studies identified genetic variants belonging to IL1RL1, TSLP and IL-33, and four loci with pleiotropic effects on eosinophil and basophil counts [GATA2 (3q21), MHC (6p21), HBS1L-MYB (6q23), and ERG (21q22)]. SUMMARY: Recent findings from biological and genetic studies on eosinophils and basophils highlight the role of epithelial cell-derived cytokines such as TSLP and IL-33 in asthma and allergic diseases

Relationships Between Psychological Factors, RPE and Time Limit Estimated by Teleoanticipation

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Influence of physical fitness on antioxidant activity and malondialdehyde level in healthy older adults

International audienceThe aim of this study was to investigate how physical fitness level could affect antioxidant activity and malondialdehyde (MDA) level at rest and in response to exhaustive exercise in healthy older adults. Fifty older adults (average age: 66.1 ± 3.8 years) were divided according to their physical fitness level into an unfit group (UG) (n = 15), a low fitness level group (LFG) (n = 18), and a high fitness level group (HFG) (n = 17). Fitness status was classified based on answers to a questionnaire about physical activity in the previous 12 months. Before and after an incremental cycle ergometer test to exhaustion, the following markers were assessed: superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione reductase, ascorbic acid, α-tocopherol, and MDA. At rest, SOD, GPX, and α-tocopherol activities were higher in the HFG (p < 0.05), whereas MDA level was lower in the LFG in comparison with the 2 other groups (p < 0.05). During the postexercise period, antioxidant activity increased only in the LFG and the HFG (GPX, SOD, and α-tocopherol). MDA level increased in all groups after the exercise (p < 0.05). In addition, MDA level was higher during the recovery period in the HFG as compared with the others groups. This study concluded that both low and high physical fitness levels help maintain better antioxidant defenses in older adults. However, a higher physical fitness level, rather than a lower physical fitness level, could increase lipid peroxidation

Lifelong Voluntary Exercise Modulates Age-Related Changes in Oxidative Stress

International audienceThe hypothesis that aging and regular physical activity could influence oxidative stress has been studied by comparing antioxidant activities (superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione reductase (GR), ascorbic acid and α-Tocopherol) and malondialdehyde level (MDA) in four groups: young sedentary (n=15; age: 20.3±2.8 years; YS), young active (n=16; age: 21.4±1.9 years; YA), old sedentary (n=15; age: 65.1±3.5 years; OS) and old active (n=17; age: 67.2±4.8 years; OA). Antioxidant activities and MDA level were assessed at rest and after an incremental exercise. There was no difference in resting antioxidant activities and lipid peroxidation between YS and OS. However, resting SOD and GR activities were higher in YA compared to OA (p<0.01 and p<0.05, respectively) and resting MDA level was higher in OA compared to YA (p<0.01). After exercise, a significant increase in SOD and GPX activities was observed in YS, YA and OA (p<0.01). Likewise, after exercise a significant increase of MDA level in YA, OS and OA (p<0.01) was observed. In addition, the comparison of YA to OA and YS to OA revealed similar antioxidant activities and lipid peroxidation between YS and OA, whereas antioxidant activities were higher in YA compared to OA. These data suggest that beneficial effects of regular physical activity in antioxidant defense and lipid peroxidation damage could be impaired by the aging process and that regular physical activity in older adults could maintain age-related decreases in antioxidant defense

Changes in oxidative stress markers and biological markers of muscle injury with aging at rest and in response to an exhaustive exercise.

PURPOSE: The aim of this study was to evaluate whether oxidative stress markers and biomarkers of muscle injury would be affected by aging at rest and in response to an incremental exhaustive exercise. METHODS: Fifteen young (20.3 ± 2.8 years) and fifteen older adults (65.1 ± 3.5 years) performed an incremental cycle ergometer test to exhaustion. Before and after exercise, oxidative stress [superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione reductase (GR), ascorbic acid, α-Tocopherol, malondialdehyde (MDA)] and muscle injury [creatine kinase (CK), lactate deshydrogenase (LDH)] biomarkers were assessed. RESULTS: At rest, there was no difference in oxidative stress markers and LDH level between the groups, however CK was significantly higher in the young group than the elderly group (p<0.05). During recovery, in comparison with resting values, a significant increase in SOD (1092 ± 145.9 vs. 1243 ± 98 U/g Hb), GPX (67.4 ± 12.7 vs. 79.2 ± 15.6 U/g Hb) and GR (6.5 ± 0.9 vs. 7.7 ± 0.5 U/g Hb) activities were observed only in the young group (p<0.05). MDA has increased only in the older group (0.54 ± 0.2 vs. 0.79 ± 0.2 µmol/l) (p<0.01). CK increased in both groups (young group: 122.5 ± 22.2 vs. 161.9 ± 18.7 UI/l; older group: 88.8 ± 34.1 vs. 111.1 ± 25.9 UI/l) (p<0.01), however LDH has increased only in the young group (400.5 ± 22.2 vs. 485 ± 18.7 UI/l) (p<0.01) without alteration in the older group (382.8 ± 34.1 vs. 418.5 ± 25.9 UI/l). CONCLUSIONS: These findings indicate that aging is associated with a decrease in antioxidant efficiency and an increase in oxidative stress damage. Furthermore, older adults would not more susceptible to exercise-induced muscle injury than young people

Cerebral oxygenation during hyperoxia-induced increase in exercise tolerance for untrained men.

International audienceThis study aimed to investigate the involvement of cerebral oxygenation in limitation of maximal exercise. We hypothesized that O2 supplementation improves physical performance in relation to its effect on cerebral oxygenation during exercise. Eight untrained men (age 27 ± 6 years; VO2 max 45 ± 8 ml min(-1) kg(-1)) performed two randomized exhaustive ramp exercises on a cycle ergometer (1 W/3 s) under normoxia and hyperoxia (FIO2 = 0.3). Cerebral (ΔCOx) and muscular (ΔMOx) oxygenation responses to exercise were monitored using near-infrared spectroscopy. Power outputs corresponding to maximal exercise intensity, to threshold of ΔCOx decline (ThCOx) and to the respiratory compensation point (RCP) were determined. Power output (W max = 302 ± 20 vs. 319 ± 28 W) and arterial O2 saturation estimated by pulse oximetry (SpO2 = 95.7 ± 0.9 vs. 97.0 ± 0.5 %) at maximal exercise were increased by hyperoxia (P < 0.05). However, the ΔMOx response during exercise was not significantly modified with hyperoxia. RCP (259 ± 17 vs. 281 ± 25 W) and ThCOx (259 ± 23 vs. 288 ± 30 W) were, however, improved (P < 0.05) with hyperoxia and the ThCOx shift was related to the W max improvement with hyperoxia (r = 0.71, P < 0.05). The relationship between the change in cerebral oxygenation response to exercise and the performance improvement with hyperoxia supports that cerebral oxygenation is limiting the exercise performance in healthy young subjects

Plasma lactate and plasma volume recovery in adults and children following high-intensity exercises.

To compare plasma lactate concentration recovery kinetics when measured and corrected for variations in plasma volume between children and adults. Nine boys (11.3 +/- 1.1 y) and 8 men (21.9 +/- 1.9 y) performed a maximal and a supramaximal exercise until exhaustion. Plasma lactate concentrations, haemoglobin and haematocrit were measured at rest, immediately on completion of exercise and after the 2nd, 5th, 12th and 30th minute of recovery. The plasma lactate concentrations and the rate of recovery were corrected for variations in plasma volume. The maximal decreases in plasma volume were significantly higher in adults than in children for maximal exercise (-18.7 +/- 2.6% vs -14.5 +/- 3.2%; p < 0.05), but similar for the supramaximal exercise (-16.9 +/- 3.4% vs -15.2 +/- 3.4%). During recovery, measured and corrected plasma lactate concentrations were significantly higher in adults. The rate of plasma lactate recovery was higher in adults for maximal exercise only. The same results were obtained when the rates of plasma lactate decrease were calculated from corrected plasma lactate concentrations. The correction of the plasma lactate concentrations for variations in plasma volume did not influence the comparison of the concentrations obtained in adults and children, or their rate of recovery

Effects of an individualized rehabilitation program prescribed by perceived exertion in women with metabolic syndrome.

PURPOSE: This study examined if the rating scale of perceived exertion (RPE ) could be used to prescribe an individualized exercise intensity at the crossover point (COP ) of substrate utilization and monitor such an individualized rehabilitation program in women with metabolic syndrome (MS). Secondly, the study investigated the effects of such a program.METHODS: Nineteen women were evaluated before and after 12 weeks of rehabilitation, which was individualized at RPE corresponding to their respective COP determined by indirect calorimetry.RESULTS: The women succeeded in regulating the exercise intensity using the targeted RPE (11.7±2.8 corresponding to 40±15 W) during the training program. Moreover, the rehabilitation program at RPE corresponding to the COP perceived between light and moderate by these women was sufficient to improve the metabolic and cardiovascular risk factors defining MS as well as the physical fitness in these women. Finally, this program, which allowed for a decrease in the prevalence of MS (-33%), was associated with a very high level of adhesion and compliance.CONCLUSIONS: This study suggests that an individualized aerobic rehabilitation program using target RPE seems to be effective and tolerable in women with MS.OBJECTIF : Cette étude a examiné si l'échelle de perception de l'effort (RPE) pouvait être utilisée pour prescrire une intensité d'exercice individualisée au point de croisement (COP) de l'utilisation des substrats énergétiques et pour monitorer un programme de réhabilitation individualisé chez des femmes atteintes du syndrome métabolique (MS). Le second objectif était d’étudier les effets d'un tel programme.MÉTHODES : Dix-neuf femmes ont été évaluées avant et après 12 semaines de réhabilitation, qui a été individualisée au RPE correspondant à leur COP respectif déterminé par calorimétrie indirecte.RÉSULTATS : Les femmes ont réussi à réguler l'intensité de l'exercice en utilisant leur RPE cible (11,7±2,8 correspondant à 40±15 W) pendant le programme de réhabilitation. De plus, le programme de réhabilitation à RPE correspondant à leur COP perçu entre léger et modéré par ces femmes a été suffisant pour améliorer les facteurs de risque métaboliques et cardiovasculaires définissant le MS ainsi que la condition physique chez ces femmes. Enfin, ce programme, qui a permis une diminution de la prévalence du MS (-33%), a été associé à un niveau très élevé d'adhésion et de compliance.CONCLUSIONS : Cette étude suggère qu'un programme de réhabilitation aérobie individualisé utilisant le RPE cible semble être efficace et tolérable chez des femmes atteintes de MS

Global lung initiative spirometry references in healthy 3-15-year-old french children

International audienceGlobal Lung Initiative spirometry references satisfactorily fit data of healthy 3- to 15-year-old French childre