The effect of prior exercise on pulmonary O(2) uptake (Vo(2)(p)), leg blood flow (LBF), and muscle deoxygenation at the onset of heavy-intensity alternate-leg knee-extension (KE) exercise was examined. Seven subjects [27 (5) yr; mean (SD)] performed step transitions (n = 3; 8 min) from passive KE following no warm-up (HVY 1) and heavy-intensity (Delta50%, 8 min; HVY 2) KE exercise. Vo(2)(p) was...

Functional closure of the human ductus arteriosus (DA) is initiated within minutes of birth by O2 constriction. It occurs by an incompletely understood mechanism that is intrinsic to the DA smooth muscle cell (DASMC). We hypothesized that O2 alters the function of an O2 sensor (the mitochondrial electron transport chain, ETC) thereby increasing production of a diffusible redox-mediator (H2O2), ...

Methods The experimental design was approved by the Ethics Committee of Federal University of Ouro Preto (UFOP)No.092/2012. Groups of female BALB/c mice (8 weeks old; 24.53±0.31g) were divided randomly in to five experimental groups as follows: Control group (CG) remained to air room; PBS group received aluminum hydroxide in phosphate buffered saline (PBS); OVA group (OVA) received ovalbumin an...

Aims. Solid O2 has been proposed as a possible reservoir for molecular oxygen in dense clouds through freeze-out processes. The aim of this work is to characterize quantitatively the physical processes that are involved in the desorption kinetics of CO–O2 ices by interpreting laboratory temperature programmed desorption (TPD) data. This information is used to simulate the behavior of CO–O2 ices...

The purpose of this study was to characterise, for the first time, the pulmonary O2 uptake (V(O2)) on-kinetic responses to step transitions to moderate and heavy intensity rowing ergometer exercise, and to compare the responses to those observed during upright cycle ergometer exercise. We hypothesised that the recruitment of a greater muscle mass in rowing ergometer exercise (Row) might limit m...

Tissues and organs in vivo are under a hypoxic condition; that is, the oxygen tension is typically much lower than in ambient air. However, the effects of such a hypoxic condition on tendon stem cells, a recently identified tendon cell, remain incompletely defined. In cell culture experiments, we subjected human tendon stem cells (hTSCs) to a hypoxic condition with 5% O2, while subjecting contr...

The effect of the partial pressure of oxygen (PO2) on the formation of vesicles, which are thought to be the site of N2 fixation in Frankia, was studied in HFPCcI3, an effective isolate from Casuarina cunninghamiana. Unlike other actinorhizal root nodules, vesicles are not produced by the endophyte in Casuarina nodules. However, in culture under aerobic conditions, large, phase-bright vesicles ...