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Koch Lauren G - - 2008
The evolution of biological complexity beyond single-celled organisms was linked temporally with the development of an oxygen atmosphere. Functionally, this linkage can be attributed to oxygen ranking high in both abundance and electronegativity amongst the stable elements of the universe. That is, reduction of oxygen provides for close to the ...
Brethauer Simone - - 2007
Intensified bioprocess development requires parallelized medium- to high-throughput experimentation with high on- and offline data density across all early scales of the development trajectory from microtiter plate via shake flask to lab-scale reactor. We developed a widespread measurement principle for intermediate scales, respirometry, into a parallelized oxygen transfer rate measurement ...
Staffieri Francesco - - 2007
OBJECTIVE: To compare the effect of 2 concentrations of oxygen in inspired gas (fraction of inspired oxygen [FIO(2)] 1.0 or 0.4) on pulmonary aeration and gas exchange in dogs during inhalation anesthesia. ANIMALS: 20 healthy dogs. PROCEDURES: Following administration of acepromazine and morphine, anesthesia was induced in each dog with ...
Kimberger Oliver - - 2007
BACKGROUND: Low tissue oxygen tension is an important factor leading to the development of wound dehiscence and anastomotic leakage after colon surgery. We tested whether supplemental fluid and supplemental oxygen can increase tissue oxygen tension in healthy and injured, perianastomotic, and anastomotic colon in an acutely instrumented pig model of ...
Kamohara Keiji - - 2007
To evaluate the effects of downsizing of the total artificial heart (TAH), we compared the anaerobic threshold (AT) values in calves with two different types of TAH (Cleveland Clinic-Nimbus TAH and the downsized MagScrew TAH). Exercise studies were performed using a treadmill in 12 calves. During the exercise, parameters to ...
Kump Lee R - - 2007
The hypothesis that the establishment of a permanently oxygenated atmosphere at the Archaean-Proterozoic transition (approximately 2.5 billion years ago) occurred when oxygen-producing cyanobacteria evolved is contradicted by biomarker evidence for their presence in rocks 200 million years older. To sustain vanishingly low oxygen levels despite near-modern rates of oxygen production ...
Su Steven W - - 2007
This paper aims to establish a block-structured model to predict oxygen uptake in humans during moderate treadmill exercises. To model the steady state relationship between oxygen uptake (oxygen consumption) and walking speed, six healthy male subjects walked on a motor driven treadmill with constant speed from 2 to 7 km/h. ...
Forrest George P - - 2007
OBJECTIVE: To determine the oxygen consumption of a person with C7 American Spinal Injury Association (ASIA) grade B tetraplegia using the Case Western Reserve/Veterans Administration (CWRU/VA) standing neuroprosthesis. DESIGN: Measure the oxygen consumption and carbon dioxide production of a person with C7 ASIA grade B tetraplegia at rest, standing in ...
Zheng Yuanhui - - 2007
Low-dimensional ZnO nanocrystals with controlled size, aspect ratio, and oxygen defects (e.g., type and concentration) are successfully prepared through simple solvothermal and thermal treatment methods. The structure of the as-synthesized samples is characterized by XRD, N2 physical adsorption, TEM, and IR and XPS spectra. The results show that the aspect ...
Pouilly J-P - - 2008
This study aimed to compare oxygen deficit during exhaustive ramp exercise (OD ramp and OD lag) with maximal oxygen deficit during a high-intensity constant-power test (MAOD). OD ramp was estimated from the difference between oxygen demand and actual oxygen uptake. OD lag was estimated using a simple equation assuming a ...
Vogiatzis I - - 2008
The aim of the present study was to investigate why blood lactate after prolonged quadriceps contraction during hiking is only marginally increased. Eight sailors performed five 3-min hiking bouts interspersed with 5-s recovery periods. Whole body oxygen uptake, heart rate and lactate were recorded, along with continuous-wave near-infrared spectroscopy measures ...
Johannigman Jay - - 2007
Closed loop control of oxygenation and ventilation during mechanical ventilatory support is essential for remote medical care in an austere environment. Closed loop control allows for expert systems to provide the current standard of care in the absence of on-site expertise. Ventilation may be controlled by simple systems incorporating patient ...
Walker Joshua - - 2007
INTRODUCTION: Some degree of recirculation occurs during venovenous extracorporeal membrane oxygenation (VV ECMO) which, (1) reduces oxygen (O2) delivery, and (2) renders venous line oxygen saturation monitoring unreliable as an index of perfusion adequacy. Ultrasound dilution allows clinicians to rapidly monitor and quantify the percent of recirculation that is occurring ...
Kimura Yoshiko - - 2007
To reveal the influence of chronic moderate smoking on physical fitness and local muscle oxygenation profile, we compared the oxygen uptake (VO2), CO2 output, respiratory rate, minute ventilation and blood lactate accumulation between six moderate smokers and ten non-smokers during incremental exercise. In order to know the difference of the ...
Rassaf Tienush - - 2007
Although the primary function of myoglobin (Mb) has been considered to be cellular oxygen storage and supply, recent studies have suggested to classify Mb as a multifunctional allosteric enzyme. In the heart, Mb acts as a potent scavenger of nitric oxide (NO) and contributes to the attenuation of oxidative damage. ...
Remington Nicole - - 2007
Studies of structure-function relationships in the respiratory proteins of marine mammals revealed unexpected variations in the number and types of hemoglobins (Hbs) present in coastal bottlenose dolphins, Tursiops truncatus. We obtained blood samples from free-ranging coastal bottlenose dolphins as a component of capture-release studies. We found that the oxygen-binding functions ...
Taubitz Anela - - 2007
Inhalation of resting conidia is usually the first step of a systemic infection caused by the opportunistic fungal pathogen Aspergillus fumigatus. In the lung, the inhaled spores encounter an environment that permits germination. However, the relative importance of certain environmental conditions for conidial activation and subsequent hyphae formation has so ...
CieĊ›lar Katarzyna - - 2007
Spatial and temporal variations in oxygen partial pressure (pO(2)) during breath-hold can be exploited to obtain important regional parameters of lung function. In the course of apnea, the oxygen concentration is known to decay exponentially. Therefore, the initial pO(2) (p(0)) can be used to represent local ventilation, and the oxygen ...
Maisch Tim - - 2007
New antibacterial strategies are required in view of the increasing resistance of bacteria to antibiotics. One promising technique involves the photodynamic inactivation of bacteria. Upon exposure to light, a photosensitizer in bacteria can generate singlet oxygen, which oxidizes proteins or lipids, leading to bacteria death. To elucidate the oxidative processes ...
Windsor Jeremy S - - 2007
INTRODUCTION: This study examines the effect of supplemental oxygen on acclimatized mountaineers at high altitude during rest and submaximal exercise. METHODS: Three healthy, acclimatized participants undertook nine periods of data collection lasting 10 min each over 2 consecutive days at 5700 m. These occurred at rest and exercise (40 and ...
Ball A J - - 2007
When considering anaesthetic masks, the quality of the mask-face seal is a key determinant of performance. This randomised crossover trial utilises expired oxygen concentration to compare the efficacy of two routinely used facemasks. Thirty subjects were randomised to breathe 100% oxygen via either a traditional reusable black rubber mask or ...
Lai Nicola - - 2007
The energy demand imposed by physical exercise on the components of the oxygen transport and utilization system requires a close link between cellular and external respiration in order to maintain ATP homeostasis. Invasive and non-invasive experimental approaches have been used to elucidate mechanisms regulating the balance between oxygen supply and ...
Liguzinski Piotr - - 2007
It has been proposed by Saltin (J Exp Biol 115: 345-354, 1985) that oxygen delivery by blood is limiting for maximal work and oxygen consumption in humans during whole body exercise but not during single-muscle exercise. To test this prediction quantitatively, we developed a static (steady-state) computer model of oxygen ...
Tisdall Martin M - - 2007
The near-IR cytochrome c oxidase (CCO) signal has potential as a clinical marker of changes in mitochondrial oxygen utilization. We examine the CCO signal response to reduced oxygen delivery in the healthy human brain. We induced a reduction in arterial oxygen saturation from baseline levels to 80% in eight healthy ...
Corazza Ivan - - 2007
In clinical practice, oxygen uptake is an indicator of cardiopulmonary performance. Most commercial systems measure oxygen uptake by collecting expired air through masks or mouthpieces which are often poorly tolerated by the patient. We have developed and validated a novel mask-free system to improve patient comfort and performance. The prototype ...
Schober Patrick - - 2007
OBJECTIVE: Carbon monoxide (CO) and oxygen compete for haemoglobin binding sites. While the effects of increased inspiratory oxygen fractions on exhaled carbon monoxide concentrations have been studied previously, the relationships between intravascular oxygen tension, blood carboxyhaemoglobin levels and expiratory CO concentrations remain unclear. We therefore studied the effects of increases ...
McGaw Iain J - - 2007
Exercise and digestive processes are known to elevate the metabolic rate of organisms independently. In this study, the effects of simultaneous exercise and digestion were examined in the graceful crab Cancer gracilis. This species exhibited resting oxygen uptake levels between 29 and 42 mg O(2) kg(-1) h(-1). In postprandial crabs, ...
Jorge R A D L V C - - 2007
The presence of pollutants in the ocean may affect different physiological parameters of animals. Oxygen consumption and ammonia excretion were evaluated in D-shaped larvae of mussels (Perna perna) exposed to zinc sulphate (ZnSO(4)) and benzene (C(6)H(6)). When compared to the control group, both pollutants presented a significant reduction in oxygen ...
Li Jia - - 2007
OBJECTIVES: The lack of accurate measurement of hemodynamics and oxygen transport has limited our understanding of Norwood physiology and postoperative management. We used measured oxygen consumption to characterize hemodynamics and oxygen transport after the classic Norwood procedure. METHODS: Fourteen neonates had continuous respiratory mass spectrometry to measure oxygen consumption (VO2). ...
Lobo Susana A L - - 2007
Sulfate reducing bacteria of the Desulfovibrio genus are considered anaerobes, in spite of the fact that they are frequently isolated close to oxic habitats. However, until now, growth in the presence of high concentrations of oxygen was not reported for members of this genus. This work shows for the first ...
Dascombe, Benjamin James
This thesis details four consecutive research investigations which were designed to examine the effect of age on the pulmonary oxygen uptake (VO2)and muscle oxygenation (mOxy) responses to exercise in well-trained cyclists. (Abridged)
Ramos Raddy L - - 2007
The principles of neurophysiology continue to be challenging topics to teach in the context of undergraduate neuroscience education. Laboratory classes containing neurophysiological demonstrations and exercises are, therefore, an important and necessary complement for covering those subjects taught in lecture-based courses. We developed a number of simple yet very instructive exercises, ...
Pereira Marta I R - - 2007
There is growing interest in resistance training, but many aspects related to this type of exercise are still not fully understood. Performance varies substantially depending on how resistance training variables are manipulated. Fatigue is a complex phenomenon usually attributed to central (neuronal) and/or peripheral (muscular) origin. Cerebral oxygenation may be ...
Iyer Rohin K - - 2007
The prominence of cardiovascular diseases has prompted investigations into alternative treatment options, including tissue engineering. Currently, the biggest limitation in cardiac tissue engineering lies in delivering oxygen to all cells within the construct. Synthetic oxygen carriers hold much promise in that they have high affinity for oxygen and can be ...
Khurana Rahul N - - 2007
PURPOSE: We describe a novel method to oxygenate intraocular irrigation solutions involving an in-line oxygenator. METHODS: Either lactated Ringer (LR) solution or balanced salt solution (BSS) was oxygenated with the FE390 Stainless In-line Oxygenation Assembly (Beer, Beer, and More Beer, Concord, CA). After running a 100-mL of solution through the ...
Nieman David C - - 2007
The purpose of this study was to assess the validity of the FitMate metabolic system (Cosmed, Rome, Italy) in measuring oxygen consumption during graded exercise. The FitMate is a new, small (20 x 24 cm) metabolic analyzer designed for measurement of oxygen consumption during rest and exercise. Subjects included 40 ...
Wold J P - - 2006
In this study, fluorescence excitation and emission matrices and multivariate curve resolution (PARAFAC) were used to detect and characterize active photosensitizers spectrally in butter. Butter samples were packed under high (air) and low oxygen (<0.05%) atmospheres and exposed to violet, green, or red light. Six photosensitizers were found: riboflavin, protoporphyrin, ...
Uemura Ryuichiro - - 2007
BACKGROUND: Recently, hepatic surgery has made remarkable progress, and it is important to use appropriate liver perfusion. We evaluated the effect of normothermic liver perfusion with the addition of fructose-1, 6-bisphosphate (FBP) and oxygenation to maintain liver parenchymal, non-parenchymal, and Kupffer cell function. MATERIALS AND METHODS: The rats were divided ...
Fink Barbara - - 2006
Factors that influence the polarographic measurement of the oxygen uptake of the cornea are reviewed. These factors include the technique, electrode assembly, oxygen reservoir, membrane material and thickness, oxygen tension of the corneal environment, duration of exposure to environmental conditions and time to application of the probe all influencing measured ...
Ashenden M J - - 2007
Haemoglobin-based oxygen carriers (HBOCs) such as Hemopure are touted as a tenable substitute for red blood cells and therefore potential doping agents, although the mechanisms of oxygen transport of HBOCs are incompletely understood. We investigated whether infusion of Hemopure increased maximal oxygen uptake (V.O 2max) and endurance performance in healthy ...
Sharma S K - - 2006
Tuberculosis (TB) is a major health problem in the developing world. In this preliminary study, we report the effect of antituberculosis treatment (ATT) on cardiopulmonary responses to exercise in patients with miliary tuberculosis (MTB). The prospective study of cardiopulmonary responses to exercise in patients with MTB within one month of ...
Sternberg Leonel - - 2006
The oxygen isotopic composition of plant cellulose is commonly used for the interpretations of climate, ecophysiology and dendrochronology in both modern and palaeoenvironments. Further applications of this analytical tool depends on our in-depth knowledge of the isotopic fractionations associated with the biochemical pathways leading to cellulose. Here, we test two ...
Hotta Norio - - 2006
The purpose of the present study was to examine the effect of unilateral lower limb suspension (ULLS) deconditioning on oxygen uptake kinetics. Eight healthy males underwent ULLS for 20 days and performed a series of 6-min square-wave transitions from rest to 60-W single-leg cycling exercises just before and after ULLS. ...
Masci Bernardo - - 2006
In the acetylation of an oxygenated calix[4]arene homologue in the presence of CsF as a base, relaxation of the reaction system to the equilibrium composition takes place through several intra- and intermolecular steps that can be easily controlled to obtain the various acetyl derivatives. The effect of different bases is ...
de Geus Bas - - 2006
The objectives of this study were to (1) continuously assess oxygen uptake and heart rate; (2) quantify the extent to which maximal whole-body cardiorespiratory capacity is utilized during climbing on four routes with the same difficulty but different steepness and/or displacement. Fifteen expert climbers underwent a maximal graded exercise test ...
Ottosen Lars D M - - 2006
Understanding the biology of reproductive organs is essential for the development of assisted reproductive techniques. There is at present no direct evidence for either the concentration and dynamics of intrauterine oxygen tension at the endometrial surface, nor its importance for the receptiveness of the endometrium. In this study a new ...
Nowak-Sliwinska Patrycja - - 2006
The efficiency of photodynamic effect (PDE) for Photofrin II (PfII), Verteporfin, and Merocyanine 540 (MC540) was compared against neoplastic cells. Triplet state lifetimes and singlet molecular oxygen quantum yields were correlated with biological effect. PfII triplet lifetime was two times longer than that of Verteporfin, however, its singlet molecular oxygen ...
Saito Takeshi - - 2006
A quantitative analysis of the oxygen concentration profile near a poly(dimethylsiloxane) (PDMS) microfluidic device was performed using scanning electrochemical microscopy (SECM). A microchannel filled with sodium sulfite (Na(2)SO(3)) aqueous solution was imaged by SECM, showing that the oxygen diffusion layer of the PDMS microchannel was observed to be hemicylindrical. Based ...
Thomas Matthew J - - 2006
Rising concerns over respiratory illnesses caused by agents such as avian influenza viruses and SARS coronavirus have prompted intensive research efforts and the resurgence of nonhuman primates as models for these human diseases. In the context of studying influenza infection and vaccine development, serial bronchoscopic procedures, including bronchial brush biopsies ...
Patel Mayur B - - 2006
BACKGROUND: Data are limited on the actions of hemoglobin based oxygen carriers (HBOCs) after traumatic brain injury (TBI). This study evaluates neurotoxicity, vasoactivity, cardiac toxicity, and inflammatory activity of HBOC-201 (Biopure, Cambridge, Mass.) resuscitation in a TBI model. METHODS: Swine received TBI and hemorrhage. After 30 minutes, resuscitation was initiated ...
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