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Objective Continuous physiological measurements during a laboratory-based exercise test can provide physiological biomarkers, such as heart rate (HR) and oxygen uptake (V̇O2) kinetics, that carry clinically relevant information. In contrast, it is not clear how continuous data generated by wearable devices during daily-life routines could provide meaningful biomarkers. We aimed to determine whether valid HR and V̇O2 kinetics can be obtained from measurements with wearable devices during outdoor walks in patients with chronic obstructive pulmonary disease (COPD). Methods HR (Polar Belt) and V̇O2(METAMAX3B) were measured during 93 physical activity transitions performed by eight patients with COPD during three different outdoor walks (ntr = 77) and a 6-minute walk test (ntr = 16). HR and V̇O2 kinetics were calculated every time a participant started a walk, finished a walk or walked upstairs. HR and V̇O2 kinetics were considered valid if the response magnitude and model fit were adequate, and model parameters were reliable. Results Continuous measurements with wearable devices provided valid HR kinetics when COPD patients started or finished (range 63%–100%) the different outdoor walks and valid V̇O2 kinetics when they finished (range 63%–100%) an outdoor walk. The amount of valid kinetics and kinetic model performance was comparable between outdoor walks and a laboratory-based exercise test ( p > .05). Conclusion We envision that the presented approach could improve telemonitoring applications of patients with COPD by providing regular, unsupervised assessments of HR kinetics during daily-life routines. This could allow to early identify a decline in the patients’ dynamic physiological functioning, physical fitness and/or health status.

Hadal trenches are considered to act as depo-centers for organic material at the trench axis and host unique and elevated biomasses of living organisms as compared to adjacent abyssal plains. To explore the diagenetic activity in hadal trench environments we quantified in situ benthic O-2 consumption rates and sediment characteristics from the trench axis of two contrasting trench systems in the Pacific Ocean; the Izu-Bonin Trench underlying mesotrophic waters and the Tonga Trench underlying oligotrophic waters. In situ oxygen consumption at the Izu-Bonin Trench axis site (9200 m; 746 +/- 103 mu mol m(-2) d(-1); n=27) was 3-times higher than at the Tonga Trench axis site (10800 m; 225 +/- 50 pmol m(-2) d(-1); n=7) presumably reflecting the higher surface water productivity in the Northern Pacific. Comparing benthic O-2 consumption rates measured in the central hadal Tonga Trench to that of nearby (60 km distance) abyssal settings (6250 m; 92 +/- 44 mu mol m(-2) d(-1); n=16) revealed a 2.5 higher activity at the trench bottom. Onboard investigations on recovered sediment furthermore revealed that the prokaryotic abundance and concentrations of phytopigments followed this overall trend (i.e minimum values at the abyssal site followed by higher values from the Tonga and lzu-Bonin Trenches axis, respectively). Excess Pb-210 profiles suggested that mass-wasting events contributed to the deposition of material enhancing the concentration of organic matter in the central trench as compared to the abyssal settings. Our results complement recent findings from the Challenger deep in the Mariana Trench area, which also revealed elevated diagenetic activity in the central trench underpinning the importance of hadal ecosystems for the deep sea carbon cycling. Hadal trenches are considered to act as depo-centers for organic material at the trench axis and host unique and elevated biomasses of living organisms as compared to adjacent abyssal plains. To explore the diagenetic activity in hadal trench environments we quantified in situ benthic O 2 consumption rates and sediment characteristics from the trench axis of two contrasting trench systems in the Pacific Ocean; the Izu-Bonin Trench underlying mesotrophic waters and the Tonga Trench underlying oligotrophic waters. In situ oxygen consumption at the Izu-Bonin Trench axis site (9200 m; 746±103 µmol m −2 d −1; n=27) was 3-times higher than at the Tonga Trench axis site (10800 m; 225±50 µmol m −2 d −1; n=7) presumably reflecting the higher surface water productivity in the Northern Pacific. Comparing benthic O 2 consumption rates measured in the central hadal Tonga Trench to that of nearby (60 km distance) abyssal settings (6250 m; 92±44 µmol m −2 d −1; n=16) revealed a 2.5 higher activity at the trench bottom. Onboard investigations on recovered sediment furthermore revealed that the prokaryotic abundance and concentrations of phytopigments followed this overall trend (i.e minimum values at the abyssal site followed by higher values from the Tonga and Izu-Bonin Trenches axis, respectively). Excess 210Pb profiles suggested that mass-wasting events contributed to the deposition of material enhancing the concentration of organic matter in the central trench as compared to the abyssal settings. Our results complement recent findings from the Challenger deep in the Mariana Trench area, which also revealed elevated diagenetic activity in the central trench underpinning the importance of hadal ecosystems for the deep sea carbon cycling.

Skeletal muscle function in patients with heart failure and reduced ejection fraction (HFrEF) greatly determines exercise capacity. However, reports on skeletal muscle fiber dimensions, fiber capillarization, and their physiological importance are inconsistent. Twenty-five moderately impaired patients with HFrEF and 25 healthy control (HC) subjects underwent muscle biopsy sampling. Type I and type II muscle fiber characteristics were determined by immunohistochemistry. In patients with HFrEF, enzymatic oxidative capacity was assessed, and pulmonary oxygen uptake (V̇o2) and skeletal muscle oxygenation during maximal and moderate-intensity exercise were measured using near-infrared spectroscopy. While muscle fiber cross-sectional area (CSA) was not different between patients with HFrEF and HC, the percentage of type I fibers was higher in HC (46 ± 15 vs. 37 ± 12%, respectively, P = 0.041). Fiber type distribution and CSA were not different between patients in New York Heart Association (NYHA) class II and III. Type I muscle fiber capillarization was higher in HFrEF compared with HC[capillary-to-fiber perimeter exchange (CFPE) index: 5.70 ± 0.92 vs. 5.05 ± 0.82, respectively, P = 0.027]. Patients in NYHA class III had slower V̇o2 and muscle deoxygenation kinetics during onset of exercise and lower muscle oxidative capacity than those in class II ( P < 0.05). Also, fiber capillarization was lower but not compared with HC. Higher CFPE index was related to faster deoxygenation ( rspearman = −0.682, P = 0.001), however, not to muscle oxidative capacity ( r = −0.282, P = 0.216). Type I muscle fiber capillarization is higher in HFrEF compared with HC but not in patients with greater exercise impairment. Greater capillarization may positively affect V̇o2 kinetics by enhancing muscle oxygen diffusion. NEW & NOTEWORTHY The skeletal myopathy of chronic heart failure (HF) includes a greater percentage of fatigable type II fibers and, for less impaired patients, greater skeletal muscle fiber capillarization. Near-infrared spectroscopy measurements of skeletal muscle oxygenation indicate that greater capillarization may compensate for reduced blood flow in mild HF by enhancing the diffusive capacity of skeletal muscle. This thereby augments and speeds oxygen extraction during contractions, which is translated into faster pulmonary oxygen uptake kinetics.

Made available in DSpace on 2018-11-26T17:16:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The South American lungfish, Lepidosiren paradoxa inhabits seasonal environments in the Central Amazon and Parana-Paraguay basins that undergo significant oscillations in temperature throughout the year. They rely on different gas exchange organs, such as gills and skin for aquatic gas exchange while their truly bilateral lungs are responsible for aerial gas exchange; however, there are no data available on the individual contributions of the skin and the gills to total aquatic gas exchange in L. paradoxa. Thus, in the present study we quantify the relative contributions of skin and gills on total aquatic gas exchange during warm (35 degrees C) and cold exposure (20 degrees C) in addition to the effects of aerial and aquatic hypercarbia on aquatic gas exchange and gill ventilation rate (f(G); 25 degrees C), respectively. Elevated temperature (35 degrees C) caused a significant increase in the contribution of cutaneous (from 0.61 +/- 0.13 to 1.34 +/- 0.26 ml. STPD.h(-1) kg(-1)) and branchial (from 0.54 +/- 0.17 to 1.73 +/- 0.53 ml. STPD.h(-1) kg(-1)) gas exchange for (V) over dotCO(2) relative to the lower temperature (20 degrees C), while (V) over dot O-2 remained relatively unchanged. L. paradoxa exhibited a greater branchial contribution in relation to total aquatic gas exchange at lower temperatures (20 and 25 degrees C) for oxygen uptake. Aerial hypercarbia decreased branchial (V) over dot O-2 whereas branchial (V) over dotCO(2) was significantly increased. Progressive increases in aquatic hypercarbia did not affect f(G). This response is in contrast to increases in pulmonary ventilation that may offset any increase in arterial partial pressure of CO2 owing to CO2 loading through the animals' branchial surface. Thus, despite their reduced contribution to total gas exchange, cutaneous and branchial gas exchange in L. paradoxa can be significantly affected by temperature and aerial hypercarbia. Sao Paulo State Univ, Dept Anim Morphol & Physiol, Coll Agr & Vet Sci, BR-14884900 Jaboticabal, SP, Brazil Natl Inst Sci & Technol Comparat Physiol, INCT Fisiol Comparada, Rio Claro, SP, Brazil Univ Sao Paulo, Dept Physiol, Fac Med Ribeirao Preto, Ribeirao Preto, SP, Brazil Fac Hlth Sci Barretos Dr Paulo Prata FACISB, Barretos, SP, Brazil Sao Paulo State Univ, Dept Anim Morphol & Physiol, Coll Agr & Vet Sci, BR-14884900 Jaboticabal, SP, Brazil FAPESP: 2005/60428-8 FAPESP: 2013/17606-9 FAPESP: 2014/12190-1

Objective: The study investigated the feasibility and potential outcome measures during acute hyperoxia in type 2 diabetes patients (DM2). Methods: Eleven DM2 patients (7 men and 4 women) were included in the study. The patients cycled (30 min at 20 % W-max) whilst breathing three different supplemental oxygen flows (SOF, 5, 10, 15 L min(-1)). During hyperoxic exercise, arterial blood gases and intra-arterial blood pressure measurements were obtained. Results: Arterial pO(2) levels increased significantly (ANOVA, p < 0.05) with SOF: 13.9 +/- 1.2 (0 L min(-1)); 18.5 +/- 1.5 (5 L min(-1)); 21.7 +/- 1.7 (10 L min(-1)); 24.0 +/- 2.3 (15 L min(-1)). Heart rate (HR) and pH increased significantly after terminating administration of hyperoxic air. Conclusions: An SOF of 15 L min(-1) appears to be more effective than 5 or 10 L min(-1). Moreover, HR, blood pressure, blood lactate and pH are not recommended as primary outcome measures.

PURPOSE: Enzyme replacement therapy (ERT) has recently became available for Pompe's disease. Data on the effects of ERT on physiological variables related to exercise tolerance have never been published. METHODS: Pulmonary gas exchange, cardiac output (by impedance cardiography), vastus lateralis muscle O2 extraction (by near-infrared spectroscopy) were determined during cycle ergometer exercise in a 50-year-old patient BEFORE and after 1, 12 and 24 months of ERT. RESULTS: At the same constant-workload submaximal exercise, rates of self-perceived exertion and values of respiratory exchange ratio, pulmonary ventilation and heart rate were lower during ERT vs.. BEFORE, suggesting an increased exercise tolerance. Peak oxygen uptake (VÙO2peak) increased by ~35% from BEFORE (0.64 L/min, or 11.4 ml/kg/min) to 1 month (0.88 L/min, or 15.7 ml/kg/min) of treatment, and did not significantly change thereafter. Also peak cardiac output significantly increased during ERT, whereas peak skeletal muscle fractional O2 extraction was unchanged compared to BEFORE. CONCLUSIONS: Improvements of peak exercise capacity and exercise tolerance at submaximal workloads were observed in a patient with Pompe's disease after 1 month of ERT, with no further changes during the ensuing treatment period (up to 24 months).

One of the most adverse effects of phosphorus (P) deficiency on N-2-fixing legumes is the generation of harmful active oxygen species which cause oxidative stress. And although oxidative stress has been widely studied in roots and shoots of various plant species, it has not yet sufficiently been documented in bean nodules so far. In this study, two recombinant inbred lines RIL115 (P-deficiency tolerant) and RIL147 (P-deficiency sensitive) of common bean and Concesa (local variety) were inoculated separately with the reference strain R. tropici CIAT899, RhM11 (R. gallicum) or RhM14 (R. tropici); two local strains of the Marrakesh region of Morocco. Nodulated plants were grown under semi-hydroponic conditions with sufficient or deficient P supply and analyzed for their oxidative responses at the flowering stage. The results indicated that P-deficiency decreased the growth of shoots (48 %) and nodules (32 %), particularly with RhM14 exhibiting the highest decrease (52 %) of nodulation. This constraint increased electrolyte leakage of nodules (40 %) as compared to leaves (20 %), especially for plants inoculated with RhM14 and CIAT899. Moreover, high H2O2 and malondialdehyde contents were noticed in P-deficient nodules of RhM14 and RhM11. These variations were associated with peroxidase activity stimulation in P-deficient nodules induced by CIAT899 and RhM14. In symbiosis with RIL115, these last strains exhibited the highest nodule phenol content. Overall, phenol content was mainly enhanced in P-deficient nodules (35 %) as compared to the leaves (16 %). It was concluded that the genotypes inoculated with CIAT899 and RhM11 are relatively P-deficiency tolerant combinations as compared to those inoculated with RhM14. Increase of oxidative stress in nodules rather than in leaves points to the need for further investigations of mechanisms that improve the root-nodule efficiency under adverse conditions.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; Although previous studies on N-2-fixing legumes have demonstrated the contribution of acid phosphatases to their phosphorus (P) use efficiency under P-deficient growth conditions, localization of these enzymes in bean nodules has not been demonstrated. In this study, phosphoenol pyruvate phosphatase (PEPase) gene transcripts were localized within the nodule tissues of two recombinant inbred lines, RIL115 (P-deficiency tolerant) and RIL147 (P-deficiency sensitive), of Phaseolus vulgaris. Nodules were induced by Rhizobium tropici CIAT899 under hydroaeroponic conditions with a sufficient versus a deficient P supply. The results indicated that PEPase transcripts were particularly abundant in the nodule infected zone and cortex of both RILs. Analysis of fluorescence intensity indicated that nodule PEPase was induced under conditions of P deficiency to a significantly higher extent in RIL147 than in RIL115, and more in the inner cortex (91%) than in the outer cortex (71%) or the infected zone (79%). In addition, a significant increase (39%) in PEPase enzyme activity in the P-deficient RIL147 correlated with an increase (58%) in the efficiency of use in rhizobial symbiosis. It was concluded that nodule PEPase is upregulated under conditions of P deficiency in the P-deficiency-sensitive RIL147, and that this gene may contribute to adaptation of rhizobial symbiosis to low-P environments.