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Saitoh Tadashi - - 2010
Near-infrared spectroscopy is a noninvasive optical technique used to monitor tissue oxygenation. Generally, the modified Beer-Lambert's law (MBL) using continuous-wave light has been used to measure active muscle oxygenation during exercise; however, it cannot measure absolute changes in the oxy- (oxy-[Hb + Mb]), deoxy- (deoxy-[Hb + Mb]), and total hemoglobin/myoglobin ...
Hiura Mikio - - 2010
The present study examined the regional differences of cortical oxygenation in the frontal lobe by near-infrared spectroscopy (NIRS) during incremental exercise tests and the precise location of NIRS was examined by brain magnetic resonance imaging (MRI). Pulmonary gas exchange and NIRS measurement during incremental cycling ergometry tests were investigated in ...
Hou Chen C Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, New York, United States of - - 2010
The space-filling fractal network in the human lung creates a remarkable distribution system for gas exchange. Landmark studies have illuminated how the fractal network guarantees minimum energy dissipation, slows air down with minimum hardware, maximizes the gas- exchange surface area, and creates respiratory flexibility between rest and exercise. In this ...
Painter Patricia - - 2009
There are many ways to measure physical functioning. Oxygen uptake at peak exercise is considered to be the most objective or 'gold-standard' measure and is determined by the integrated functioning of multiple physiological systems. Renal failure can affect the functioning of several of these systems which results in low levels ...
Campbell Andrew - - 2009
Low steady state haemoglobin oxygen saturation in patients with sickle cell anaemia has been associated with the degree of anaemia and haemolysis. How much pulmonary dysfunction contributes to low saturation is not clear. In a prospective study of children and adolescents with sickle cell disease aged 3-20 years at steady ...
Smith T B - - 2009
This study reviews the predictive value of maximum oxygen consumption (VO2max) and anaerobic threshold, obtained through cardiopulmonary exercise testing, in calculating peri-operative morbidity and mortality in non-cardiopulmonary thoraco-abdominal surgery. A literature review provided nine studies that investigated either one or both of these two variables across a wide range of ...
Tobias Joseph D - - 2009
Methemoglobinemia results from the oxidation of the iron in the hemoglobin molecule from the ferrous to the ferric state. Methemoglobinemia may result from congenital deficiencies of enzymes that normally convert methemoglobin (metHb) to hemoglobin, alterations in the hemoglobin molecule itself or, most commonly, from medications or toxins. As metHb cannot ...
Powell Mark D - - 2009
The occurrence of spinal deformity in aquaculture can be considerable, and a high rate of deformity has been suggested in triploid smolts in Tasmania. However, the physiological performance of fish with skeletal deformities has not been addressed. The swimming performance and oxygen consumption of triploid Atlantic salmon smolts with either ...
Lai Nicola - - 2009
Noninvasive, continuous measurements in vivo are commonly used to make inferences about mechanisms controlling internal and external respiration during exercise. In particular, the dynamic response of muscle oxygenation (Sm(O(2))) measured by near-infrared spectroscopy (NIRS) is assumed to be correlated to that of venous oxygen saturation (Sv(O(2))) measured invasively. However, there ...
Midgley Adrian W - - 2009
In this study, criteria are used to identify whether a subject has elicited maximal oxygen uptake. We evaluated the validity of traditional maximal oxygen uptake criteria and propose a novel set of criteria. Twenty athletes completed a maximal oxygen uptake test, consisting of an incremental phase and a subsequent supramaximal ...
Woods H Arthur - - 2009
Compared to temperate and tropical relatives, some high-latitude marine species are large-bodied, a phenomenon known as polar gigantism. A leading hypothesis on the physiological basis of gigantism posits that, in polar water, high oxygen availability coupled to low metabolic rates relieves constraints on oxygen transport and allows the evolution of ...
Wan Jennifer J - - 2009
BACKGROUND: Muscle tissue oxygen monitoring (PmO2) holds promise as a continuous guide to resuscitation after hemorrhagic shock, but the relationship of muscle tissue oxygen to perfusion has not been described previously. On the other hand, brain tissue oxygen PbrO2 and perfusion as measured by cerebral blood flow (CBF) are already ...
Ando Soichi - - 2009
The purpose of this study was to test if increased oxygen availability affected simple reaction time (RT) to peripheral visual stimuli during exercise. Twelve male participants performed RT tasks at rest, during cycling with three different workloads (100, 150, and 200 W), and after exercise. We fractionated RT into Premotor ...
Lin Zhenkun - - 2009
A fuel-rich premixed laminar methyl methacrylate (MMA)/O(2)/Ar flame at low pressure (30 Torr) with the equivalence ratio (phi) of 1.60 is studied in this work. Synchrotron vacuum ultraviolet photoionization combined with molecular beam mass spectrometry is employed to identify the combustion intermediates including isomeric intermediates. The observed combustion intermediates can ...
Booth David T - - 2009
Swimming effort and oxygen consumption of newly emerged green turtle Chelonia mydas hatchlings was measured simultaneously and continuously for the first 18 h of swimming after hatchlings entered the water. Oxygen consumption was tightly correlated to swimming effort during the first 12 h of swimming indicating that swimming is powered ...
Shephard Roy J - - 2009
Over the past 13 years, Noakes and his colleagues have argued repeatedly for the existence of a 'Central Governor', a specific brain centre that provides a feed-forward regulation of the intensity of vigorous effort in order to conserve homeostasis, protecting vital organs such as the brain, heart and skeletal muscle ...
O'Connor James P B JP Imaging Science and Biomedical Engineering, University of Manchester, Manchester, UK. - - 2009
Magnetic resonance imaging has shown promise for evaluating tissue oxygenation. In this study differences in the tissue longitudinal relaxation rate (R(1)) and effective transverse relaxation rate (R(*)(2)), induced by inhalation of pure oxygen and carbogen, were evaluated in 10 healthy subjects. Significant reductions in R(1) were demonstrated following both oxygen ...
Mello Roger G T RG Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, P. O. Box 68.510, 21941-972 Rio de Janeiro RJ, Brazil. - - 2009
This work aims at testing the influence of the maximal oxygen uptake test and prolonged cycle ergometer exercise on sway density plot (SDP) parameters of postural control. Sixteen healthy male subjects were submitted to stabilometric tests with eye open and closed, before and after two different exercises. The maximal oxygen ...
Seifert T - - 2009
Beta-blockers reduce exercise capacity by attenuated increase in cardiac output, but it remains unknown whether performance also relates to attenuated cerebral oxygenation. Acting as their own controls, eight healthy subjects performed a continuous incremental cycle test to exhaustion with or without administration of the non-selective beta-blocker propranolol. Changes in cerebral ...
Khaw K S - - 2009
BACKGROUND: Controversy still exists if the administration of supplementary oxygen to patients having emergency Caesarean section (CS) under regional anaesthesia is beneficial or potentially harmful. Therefore, in a prospective double-blinded study, we randomized patients having emergency CS under regional anaesthesia to receive either air or 60% oxygen until delivery and ...
Sakaue Hirokazu - - 2008
Supplementation with oxygen is fundamental in rescue and emergency medicine. However, transportation of oxygen cylinders or a rigid hyperbaric chamber requires large work forces. Also, oxygen in a cylinder may be completely consumed during a rescue action. The oxygen concentrators, which enrich the oxygen percentage of ambient air, may free ...
Yamazaki H - - 2008
1. The objective was to investigate the transport of an anticancer agent carboplatin across the blood-brain barrier in combination with hyperbaric oxygenation treatment. An in vitro well-validated model of bovine brain capillary endothelial cells was used. 2. A transendothelial transport of doxorubicin, a known P-glycoprotein substrate, was enhanced 1.5-fold by ...
Currow David C - - 2008
INTRODUCTION: Oxygen for refractory dyspnea at the end of life is commonly prescribed, even when the criteria for long-term home oxygen therapy are not met. Is palliative oxygen less likely to be prescribed when a person lives alone at the end of life? METHODS: Three years of consecutively collected clinical ...
Laubach Hans-Joachim - - 2008
Photodynamic therapy (PDT) is a viable treatment option for a wide range of applications, including oncology, dermatology, and ophthalmology. Singlet oxygen is believed to play a key role in the efficacy of PDT, and on-line monitoring of singlet oxygen during PDT could provide a methodology to establish and customize the ...
Ota Kei - - 2008
Percutaneous cardiopulmonary support (PCPS) has been applied for cardiopulmonary arrest (CPA). We have developed a novel method of cardiopulmonary resuscitation using PCPS combined with liposome-encapsulated hemoglobin (TRM645) to improve oxygen delivery to vital organs. Ventricular fibrillation was electrically induced to an adult goat for 10 min. Next, PCPS (30 ml/kg/min, ...
Arieli Ran - - 2008
No symptoms related to central nervous system (CNS) oxygen toxicity have been reported when diving with oxygen rebreathers at depths shallower than 3 msw. We hypothesised that recovery from CNS oxygen toxicity will take place when the PO(2) is less than 130 kPa. We exposed rats to a high PO(2) ...
Drummond Michael B - - 2008
BACKGROUND: Continuous oxygen therapy is not recommended for emphysema patients who are not hypoxemic at rest, although it is often prescribed. Little is known regarding the clinical characteristics and survival of nonhypoxemic emphysema patients using continuous oxygen. Analysis of data from the National Emphysema Treatment Trial (NETT) offers insight into ...
Mansjoer Arif - - 2008
Critical ill patients experience acute physiological changes because the body cannot fulfill the oxygen demand to perform normal aerobic metabolism. Factors determining oxygen delivery include cardiac output, hemoglobin, and oxygen saturation. Incapability to fulfill adequate oxygen of the body to produce adenosine triphosphate (ATP) may occur due to decreased oxygen ...
Feldman Chad M - - 2008
Sustained myocardial recovery and reversal of heart failure has been reported with the use of left ventricular assist devices (LVADs). However, clinical predictors of sustained recovery have not been clearly defined, and little information exists regarding exercise improvement in LVAD patients. Therefore, we sought to determine whether peripheral oxygen delivery ...
Spiering Barry A - - 2008
Previous research has shown that L-carnitine L-tartrate (LCLT) supplementation beneficially affects markers of hypoxic stress following resistance exercise. However, the mechanism of this response is unclear. Therefore, the primary purpose of this study was to determine the effects of LCLT supplementation on muscle tissue oxygenation during and after multiple sets ...
Ao Yoko - - 2008
Since we have been exposed to excessive amounts of stressors, aromatherapy for the relaxation has recently become very popular recently. However, there is a problem which responds to light with the essential oil used by aromatherapy. It is generally believed that singlet oxygen is implicated in the pathogenesis of various ...
Schaefer Meike - - 2009
Singlet oxygen was generated by means of rose bengal under irradiation by visible light. N(1)-acetyl-5-methoxykynuramine (AMK) was rapidly destroyed by this reactive oxygen species, whereas its formylated precursor, N(1)-acetyl-N(2)-formyl-5-methoxykynuramine (AFMK), was remarkably inert. At photon fluence rates of 1400 mumol photons/m(2)s, and using 20 mum rose bengal, most of initially ...
Dhar V - - 2008
OBJECTIVES: Airway fires pose a risk during laser microlaryngoscopy, and neurosurgical cotton patties, used to prevent tissue injury from stray laser beams, are a potential ignition source. Using a configuration approximating clinical practice, we experimentally assessed the relative impact of changing different 'fire triad' components on the occurrence of airway ...
Kruijt Bastiaan - - 2008
The presence of phased protoporphyrin IX (PpIX) bleach kinetics has been shown to correlate with esophageal response to 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) in animal models. Here we confirm the existence of phased PpIX photobleaching by increasing the temporal resolution of the fluorescence measurements using the therapeutic illumination and long ...
Wüst Rob C I - - 2008
When measuring breath-by-breath (BbB) oxygen uptake at the mouth (V MO2 ) as the difference between the amount of inspired and expired oxygen, BbB variation in lung oxygen stores due to BbB variation in end-expiratory lung volume (VLET) introduces an error leading to a decreased signal-to-noise ratio when compared to ...
Lundby C - - 2008
This study was performed to test the hypothesis that administration of recombinant human erythropoietin (rHuEpo) in humans increases maximal oxygen consumption by augmenting the maximal oxygen carrying capacity of blood. Systemic and leg oxygen delivery and oxygen uptake were studied during exercise in eight subjects before and after 13 wk ...
Krishna Rao Dasari V - - 2008
The impact of different levels of agitation speed, carbondioxide and dissolved oxygen concentration on the key parameters and production of rhG-CSF in Escherichia coli BL21(DE3)PLysS were studied. Lower carbondioxide concentrations as well as higher agitation speeds and dissolved oxygen concentrations led to reduction in the acetate concentrations, and enhanced the ...
Alcaraz-García M J - - 2008
Oxygen toxicity is a problem in diving which can have fatal consequences in the water. When divers use closed-circuit oxygen rebreathing apparatus they are taking only oxygen 100% and this hyperoxic exposure increases the generation of reactive oxygen species (ROS) in biological tissues. The objective of the present study is ...
Borghi-Silva A - - 2008
BACKGROUND: Respiratory muscle unloading during exercise could improve locomotor muscle oxygenation by increasing oxygen delivery (higher cardiac output and/or arterial oxygen content) in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixteen non-hypoxaemic men (forced expiratory volume in 1 s 42.2 (13.9)% predicted) undertook, on different days, two constant work ...
McGaw Iain J - - 2008
The gastric physiology of the Dungeness crab, Cancer magister, was investigated over a range of oxygen tensions. Postprandial crabs reacted differently to hypoxia compared with unfed animals. The bradycardic response in postprandial animals was reduced, suggesting a summation of responses with feeding. A similar pattern was observed for ventilation rate. ...
Stramma Lothar - - 2008
Oxygen-poor waters occupy large volumes of the intermediate-depth eastern tropical oceans. Oxygen-poor conditions have far-reaching impacts on ecosystems because important mobile macroorganisms avoid or cannot survive in hypoxic zones. Climate models predict declines in oceanic dissolved oxygen produced by global warming. We constructed 50-year time series of dissolved-oxygen concentration for ...
Liu K Ruth - - 2008
Oxygenation changes in the left prefrontal cortex during language processing were assessed with near-infrared spectroscopy (NIRS). Oxyhemoglobin and deoxyhemoglobin concentrations at the Fp1 site during 5 min of resting with eyes closed (control), followed by 5 min of reading aloud, were monitored. A statistically significant change in the oxyhemoglobin concentration ...
Wang Alice - - 2008
Melanin, a major pigment found in retinal pigment epithelium (RPE) cells, is considered to function in dual roles, one protective and one destructive. By quenching free radical species and reactive oxygen species (ROS) melanin counteracts harmful redox stress. However, melanin is also thought to be capable of creating ROS. In ...
Crawford D M - - 2008
Following an explosion on board a British Navy submarine operating under the Polar ice cap, a 33-year-old sailor fought a fire without protective breathing apparatus. He was found confused, with soot about his nares. A suspected diagnosis of carbon monoxide (CO) poisoning was rapidly confirmed on site using a new ...
Nasilowski Jacek - - 2008
BACKGROUND: Differences in oxygen delivery between portable oxygen concentrators (POC) and liquid oxygen (LO) portable units, pose a question if POCs are equally effective as LOs in reducing exercise-induced hypoxaemia. DESIGN: Randomized, single-blind clinical trial. PATIENTS: Thirteen COPD patients (means: age 66+/-11 year, FEV(1) 35.2+/-13.7% predicted) and respiratory failure (means: ...
Frappell Peter B - - 2008
The 'supply' of substrates should match 'demand' for energy utilization and not limit it. Integration of supply to demand would be expected to occur during ontogeny. As a result of a short gestation and protracted lactation most development in marsupials occurs ex utero in a thermally stable pouch, hence there ...
Hale Tudor - - 2008
This paper provides a thumb-nail sketch of some of the key issues that have been instrumental in the development of the scientific study of exercise, and more particularly sports, physiology. Those who have had the pleasure of reading the American Physiological Society's publication Exercise Physiology in its "People and Ideas" ...
Bianchini Jr I - - 2008
This study presents a kinetic model of oxygen consumption during aerobic decomposition of detritus from seven species of aquatic macrophytes: Cabomba furcata, Cyperus giganteus, Egeria najas, Eichhornia azurea, Salvinia auriculata, Oxycaryum cubense and Utricularia breviscapa. The aquatic macrophytes were collected from Oleo Lagoon situated in the Mogi-Guaçu river floodplain (SP, ...
Riser Stephen C - - 2008
The question of whether the plankton communities in low-nutrient regions of the ocean, comprising 80% of the global ocean surface area, are net producers or consumers of oxygen and fixed carbon is a key uncertainty in the global carbon cycle. Direct measurements in bottle experiments indicate net oxygen consumption in ...
Sloman Katherine A - - 2008
Animals living in the intertidal zone experience regular, predictable fluctuations in physical parameters including temperature, oxygen and salinity and rely on behavioural, physiological and biochemical mechanisms to cope with environmental variation. In the present study, behavioural strategies induced by aquatic hypoxia (e.g. emergence) were performed at similar oxygen tensions across ...
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