Patients with chronic obstructive pulmonary disease (COPD) frequently develop nocturnal oxygen desturation because of alveolar hypoventilation, worsening of ventilation-perfusion mismatch, and sometimes obstructive sleep apnoeas. In contrast, little is known about their oxygen status during the various activities of daily life. The aim of this study was to compare the oxygen saturation profile ...

It remains controversial whether lactate formation during progressive dynamic exercise from submaximal to maximal effort is due to muscle hypoxia. To study this question, we used direct measures of arterial and femoral venous lactate concentration, a thermodilution blood flow technique, phosphorus magnetic resonance spectroscopy (MRS), and myoglobin (Mb) saturation measured by 1H nuclear MRS in...

Unrestrained, quiescent starry flounder maintained approximately normal levels of O2 uptake in the face of severe experimental anaemia. At haematocrits above about 5%, the only major compensation was a reduction in venous O2 tension which lowered venous saturation and thereby kept a constant difference between arterial and venous O2 contents. Below a haematocrit of about 5%, this difference dec...

To examine seasonal and regional variabilities in metabolic status the coupling of net community production (NCP) air-sea CO2 fluxes western Arctic Ocean, we collected underway measurements surface O2/Ar partial pressure (pCO2) summers 2016 2018. With a box-model, demonstrate that accounting for local sea ice history (in addition to wind history) is important estimating NCP from biological oxyg...

STUDY OBJECTIVE In COPD, it has been shown that peripheral muscle dysfunction is a factor determining exercise intolerance. We examined the hypothesis that exercise capacity of patients with idiopathic pulmonary fibrosis (IPF) is, at least in part, determined by peripheral muscle dysfunction. METHODS Maximum oxygen uptake (V(O2)max) was evaluated in 41 consecutive patients with IPF, along wit...

The relative contributions to O2 consumption made by the protozoal and bacterial populations present within the rumen were determined by using an open-type oxygen electrode system. Measurements indicated that two separate microbial populations contributed approximately equally to ruminal O2 consumption over the O2 concentration range experienced in situ (0.25 to 1.0 microM). The populations wer...

Air-breathing fishes represent interesting organisms in terms of understanding the physiological changes associated with the terrestrialization of vertebrates, and, further, are of great socio-economic importance for aquaculture in Southeast Asia. To understand how environmental factors, such as high temperature, affect O2 transport in air-breathing fishes, this study assessed the effects of te...

Major evolutionary trends in animal physiology have been heavily influenced by atmospheric O2 levels. Amongst other important factors, the increase in atmospheric O2 which occurred in the Pre-Cambrian and the development of aerobic respiration beckoned the evolution of animal organ systems that were dedicated to the absorption and transportation of O2, e.g., the respiratory and cardiovascular s...

A novel commercial training mask purportedly allows for combined respiratory muscle training and altitude exposure during exercise. We examined the mask's ability to deliver on this claim. Ten men completed three bouts of treadmill exercise at a matched workload (60%VO2peak) in a controlled laboratory environment. During exercise, the mask was worn in 2 manufacturer-defined settings (9,000 ft [...

Background: Lymphangioleiomyomatosis (LAM) is a progressive lungs disease that affects women at reproductive years. Sirolimus inhibits mammalian target of rapamycin (mTOR) and its administration in past studies was hopeful in treatment of patients with LAM. The aim of this study was to evaluate sirolimus therapy on lung function in LAM patients. Methods: We conducted a trial to evaluate the ef...