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Bush Jill A - - 2006
This study was the first study to examine the three circulatory biocompartments (plasma, white blood cell layer (WBC) and red blood cell layer (RBC)) and determine PF concentrations before and after exercise. Proenkephalin peptide F (PF) is an enkephalin-containing peptide found predominantly within the adrenal medulla. PF is co-packaged with ...
Rodriguez-Proteau R - - 2006
The hypothesis tested was that specific flavonoids such as epicatechin gallate, epigallocatechin gallate, genistein, genistin, naringenin, naringin, quercetin and xanthohumol will modulate cellular uptake and permeability (P(e)) of multidrug-resistant substrates, cyclosporin A (CSA) and digoxin, across Caco-2 and MDCKII-MDR1 cell transport models. (3)H-CSA/(3)H-digoxin transport and uptake experiments were performed with ...
Petroianu G A - - 2006
Oximes are cholinesterase reactivators of use in poisoning with organophosphorus compounds. Pralidoxime (PRX) is used clinically as an adjunct to atropine in such exposure. Clinical experience with PRX (and other oximes) is, however, disappointing and routine use has been questioned. In addition it is known that oximes are not equally ...
Hess J R - - 2006
BACKGROUND: Red blood cell (RBC) storage solutions work in a narrow pH range between 7.2 and 6.4. While keeping RBC within that pH range, ATP production can be increased by buffering or dilution. STUDY DESIGN AND METHODS: In the first study, 12 units of packed CP2D RBCs were pooled in ...
Julian David - - 2005
Sulfide-tolerant marine invertebrates employ a variety of mechanisms to detoxify sulfide once it has entered their bodies, but their integumentary, respiratory epithelium and circulatory cells may still be exposed to toxic sulfide concentrations. To investigate whether sulfide exposure is toxic to mitochondria of a sulfide-tolerant invertebrate, we used the fluorescent ...
Temiz Artmann A - - 2006
Erythrocytes (RBC) from untrained male Wistar rats and rat glomerular endothelial cells (EC) were used to investigate the effects of acute exercise (speed: 20 m/min, slope: 0, duration: 1 hour) on RBC membrane protein oxidation and adhesion to cultured EC. Experimental animals were divided into juvenile (age 10 weeks) and ...
Beneke Ralph - - 2005
The pathophysiology of exercise related haemolysis is not thoroughly understood. We investigated whether exercise related haemolysis (1) is associated with alterations of red blood cell (RBC) membrane proteins similar to those found in inherited anaemic diseases, (2) can be induced with a non-running exercise mode, (3) is related to exercise ...
Petibois Cyril - - 2005
BACKGROUND: We tested the hypothesis that endurance training may reduce exercise oxidative stress damage on erythrocytes. METHODS: Fifteen subjects performed a standardized endurance exercise at 75% of maximal oxygen consumption weekly during a 19-week training period. Blood samples taken before and after exercise were analyzed by Fourier transform-infrared (FT-IR) spectrometry ...
Petibois Cyril - - 2005
We tested the hypothesis that usual exercise oxidative stress strongly affects erythrocytes viability. A 120-min physical exercise with progressive intensity was used as a model of oxidative stress. FT-IR spectrometry was used to determine structural changes in erythrocyte contents (phospholipids, proteins, lactate, and glucose) from blood samples taken every 20 ...
Monchanin Géraldine - - 2005
PURPOSE: This study investigated hemorheological parameters in response to exercise in sickle cell trait (SCT) athletes with or without alpha-thalassemia METHODS: Six athletes with SCT (HbAS), 7 athletes with SCT and alpha-thalassemia (HbASAT), and 10 control athletes (HbAA) performed a progressive and maximal exercise test on cycloergometer. Blood viscosity (etab), ...
Kayatekin Berkant Muammer - - 2005
This study aimed to determine whether high-dose antioxidant supplementation had an impact on the acute exercise effects related to erythrocyte membrane mechanics. Experimental animals (n=32) were divided into four groups as control, exercised, supplemented, and supplemented + exercise. Four-week antioxidant supplementation (vitamin C, vitamin E, and zinc) was applied to ...
Sentürk Umit Kemal - - 2005
Intravascular hemolysis is one of the most emphasized mechanisms for destruction of erythrocytes during and after physical activity. Exercise-induced oxidative stress has been proposed among the different factors for explaining exercise-induced hemolysis. The validity of oxidative stress following exhaustive cycling exercise on erythrocyte damage was investigated in sedentary and trained ...
Richardson Matt - - 2005
Human splenic contraction occurs both during apnea and maximal exercise, increasing the circulating erythrocyte volume. We investigated the hematological responses to 3 maximal apneas performed by elite apneic divers, elite cross-country skiers, and untrained subjects. Post-apnea hemoglobin concentration had increased in all groups, but especially in divers. The increases disappeared ...
Pattillo Robin E - - 2005
This study determined and compared rates and mechanisms of lactate transport in red blood cells (RBCs) of persons with 1) sickle cell disease (HbSS), 2) sickle cell trait (HbAS), and 3) a control group (HbAA). Blood samples were drawn from 30 African-American volunteers (10 HbSS, 10 HbAS, 10 HbAA). Lactate ...
Lukaski Henry C - - 2005
BACKGROUND: The role of zinc in promoting physiologic function during exercise is not well understood. Although some zinc-containing enzymes are postulated to regulate energy expenditure, data are limited on the effect of restricted dietary zinc on metabolic responses during exercise. OBJECTIVE: This study determined the effects of low zinc intake ...
Friedrich Björn - - 2005
Standard haemodialysis (HD) rapidly alters osmolality and composition of extracellular fluid and, thus, challenges cell volume constancy. Cell volume-sensitive genes upregulated by osmotic cell shrinkage include those encoding for taurine transporter TAUT as well as for serum- and glucocorticoid-inducible kinase SGK1. Six HD patients were haemodialysed for 4 h with ...
Kennedy Sarah L - - 2005
INTRODUCTION/PURPOSE: Exercise modulates many aspects of physiology. The purpose of the current experiment was to characterize the impact of regular, moderate physical activity on resting, baseline measures of cellular immunity blood lipids, and muscle enzyme. METHODS: Male Fischer 344 rats were housed with either mobile (run, N = 10) or ...
Stoiber B - - 2005
In situations where capillary perfusion in skeletal muscles is limited, changes in blood flow play an important role. Especially alterations in intrinsic erythrocyte factors like red cell aggregation and deformability would increase blood flow resistance. In our study we investigated whether whole blood and plasma viscosity influence exercise tolerance during ...
Dumay Olivier - - 2004
The concentration of phenolic compound was measured in the seagrass Posidonia oceanica when interacting with two Bryopsidophyceae, Caulerpa taxifolia and Caulerpa racemosa, between May 1999 and May 2000. These measurements were performed on adult and intermediate leaves and in sheaths of the seagrass. Sampling was carried out at three stations ...
Bergeron Michael F - - 2004
OBJECTIVE: To examine effects of exercise in the heat and fluid intake on erythrocyte sickling and neutrophil activation in carriers of sickle cell trait (HbAS). DESIGN, SETTING, AND PARTICIPANTS: Six African American men (2 HbAS; 42% HbS, 4 HbAA; 20.7 +/- 0.8 years; 87.4 +/- 9.6 kg) participated in 2 ...
Pawlotsky Yves - - 2004
The aim of the study was to simplify the first Sigma erythrocyte sedimentation rate (ESR) method (manual hematocrit adjustment to 0.35, sum of 4 sedimentation levels) and to confirm its clinical relevance. The erythrocyte sedimentation rate of undiluted blood samples from 576 patients was measured simultaneously with and without manual ...
Connes P - - 2004
Several studies have suggested that athletes with low hemoglobin saturation during exercise may experience impaired pulmonary blood gas exchange during maximal exercise. Blood viscosity may be implicated in exercise-induced pulmonary hemorrhage in race horses. We hypothesized that blood rheology may contribute to impaired gas exchange and reduced hemoglobin saturation during ...
Ferrone Frank A - - 2004
Under physiological conditions, sickle hemoglobin, a natural mutant of human hemoglobin A with a surface hydrophobic valine in place of a negatively charged glutamic acid, polymerizes at high volume occupancy. Equilibrium solubility of sickle hemoglobin entails activity coefficients that can approach 10(3) at high concentrations. Polymerization occurs by homogeneous and ...
Moshelion Menachem - - 2004
The osmotic water permeability coefficient (P(f)) of plasma membrane of maize (Zea mays) Black Mexican Sweet protoplasts changed dynamically during a hypoosmotic challenge, as revealed using a model-based computational approach. The best-fitting model had three free parameters: initial P(f), P(f) rate-of-change (slope(P(f))), and a delay, which were hypothesized to reflect ...
Aoi W - - 2004
We investigated the effect of sustained swimming exercise on the increase in monocarboxylate transporter 1 (MCT1) concentration and its ability to regulate pH homeostasis in rat erythrocytes. Male Sprague-Dawley rats aged 9 weeks were divided into sedentary and swimming groups for both 1- and 3-week experiments. The exercise group swam ...
Boselli Emanuele - - 2004
Monomeric phenols, color and copigmentation parameters, pigments with different chemical structure, tannin, glucose, fructose, glycerol, ethanol, and organic acids were determined in DOC red wines from Marche (Italy), obtained during three different vintages ranging from 1996 to 2000. The intensity of the bitter and astringent tastes of the wines was ...
Koury Josely C - - 2004
The purpose of this study was to compare zinc and copper biochemical indices of antioxidant status and their relationship in elite athletes of different modalities: aerobic with high-impact (triathletes, n = 10 and long-distance runners, n = 12), anaerobic with high-impact (short-distance runners, n = 9), and anaerobic with low-impact ...
Eike Julie H - - 2004
Various oxidized mono/di/tri/poly saccharides were studied as potential hemoglobin (Hb) cross-linkers in order to produce oxygen carriers with high oxygen affinities (low P(50)'s) and high molecular weights (therefore lower macromolecular diffusivities compared to tetrameric Hb). Such physical properties were desired to produce polymerized hemoglobins (PolyHbs) with oxygen release profiles similar ...
Wettstein Reto - - 2004
Microcirculatory perfusion deficits and impaired tissue oxygenation in nonvital organs frequently occur after hemorrhage and they contribute to potentially lethal complications. The aim of this study was to test the influence of colloid osmotic pressure, viscosity, and red blood cell (RBC) content of the resuscitative fluid on metabolic disorder, perfusion, ...
Connes Philippe - - 2004
Exercise transiently increases blood viscosity: however data on red cell deformability in this process remain inconsistent, since studies report either impairment (proportional to blood lactate accumulation), a lack of effect, or even in some cases an improvement. To test whether these inconsistencies may be due to physiological differences among populations ...
Svenmarker S - - 2004
BACKGROUND: Measurement of the activated clotting time (ACT) represents a standard method for coagulatory assessments. The test employs specific agents to trigger the coagulation process. The present study aimed to compare kaolin (Hemotec) versus a combination of silica, kaolin and phospholipid (Hemochron Jr) ACTs. METHODS: Hemotec and Hemochron Jr ACT ...
Martin-Romero Francisco Javier - - 2004
The production of peroxynitrite during 3-morpholinosydnonimine (SIN-1) decomposition can be continuously monitored, with a sensitivity < or = 0.1 microM, from the kinetics of NADH fluorescence quenching in phosphate buffers, as well as in buffers commonly used with cell cultures, like Locke's buffer or Dulbecco's modified Eagle's medium (DMEM-F12). The ...
Varlet-Marie Emmanuelle - - 2004
Blood lactate increases during exercise. Although this increase was classically interpreted as a "Pasteur-like effect" resulting from anaerobiosis, it is now clear that it mostly results from a shift in the balance of oxidation of substrates in the muscle, with carbohydrate becoming the predominant fuel. However, we have repeatedly observed ...
Varlet-Marie Emanuelle - - 2004
Contemporary sports imply huge training volumes, with thus an increasing danger of overloading. The timely detection of the state of overloading in the organism as a whole or in skeletal muscles presents a difficult and complicated problem. A standardized questionnaire has been proposed by the French consensus group on overtraining ...
Lindinger Michael I - - 2003
We tested the hypothesis that exercise-induced changes in plasma composition result in peak stimulation of erythrocyte unidirectional K+ (JK,in) and net K+ (JK,net) transport within the first 120 s. In experimental series 1 (7 men; 2 women), plasma [K+] was continuously measured in vitro (37 degrees C) after the addition ...
Valeri C Robert - - 2003
BACKGROUND: RBC volume, 24-hour posttransfusion survival, and life span can be measured with radio-isotopes and nonradioactive procedures. STUDY DESIGN AND METHODS: RBC volume was measured directly with autologous baboon RBCs labeled with biotin-X-N-hydroxysuccinimide (NHS), 51Cr, 99mTc, and 111In-oxine and indirectly from the 125I plasma volume and the total body Hct. ...
Bonacker Daniela - - 2004
In order to investigate the chromosomal genotoxicity of nitrobenzene and benzonitrile, we studied the induction of micronuclei (MN) by these test compounds in V79 cells, as well as effects on the formation and stability of microtubules and on motor protein functions. No cytotoxicity was seen in V79 cell cultures in ...
Hess John R - - 2003
BACKGROUND: Better storage can improve RBC availability and safety. Optimizing RBC ATP production and minimizing hemolysis has allowed progressively longer storage. STUDY DESIGN AND METHODS: In the first study, 24 units of packed CPD RBCs were pooled in groups of four, realiquoted, and added to 300 mL of one of ...
Bailey David G - - 2003
OBJECTIVES: Our objective was to assess the importance of bergamottin in drug interactions through comparisons between grapefruit juice and lime juice and the potential for drug interactions with red wine. METHODS: Bergamottin content and in vitro reversible/irreversible inhibition of cytochrome P450 (CYP) 3A4 monooxygenase activities were determined for grapefruit and ...
Rouffiac Valérie - - 2003
We have previously established new ultrasonic indexes for erythrocyte aggregation using a Couette device, and validated them toward the Rayleigh's theory and reproducibility. Two hydrodynamic protocols were applied on various suspensions and their aggregation degrees were characterized by: 1. for the decreasing shear rates protocol: the power P(US) at the ...
Tsuda Kazushi - - 2003
1. The present study was undertaken to investigate the effects of aerobic physical exercise on membrane function in mild essential hypertension. 2. Hypertensive patients were divided into an exercise group (n = 8) and a non-exercise (control) group (n = 8). Physical exercise within the intensity of the anaerobic threshold ...
Awasthi V D - - 2003
To determine the largest size of liposomes that can retain stealth behavior conferred by poly(ethylene glycol)-DSPE, neutral liposomes were studied in rabbits for their circulation and distribution. Five sizes (136.2, 165.5, 209.2, 275 and 318 nm) of liposomes (DSPC, Cholesterol, PEG-DSPE and alpha-tocopherol, 90:80:4.5:3.9 molar ratio) were made by extrusion ...
Sara Fagnété - - 2003
OBJECTIVE: The objective of this study was to assess lactic response (mmol/L) during incremental exercise in a specific population of men and women with sickle cell trait. SUBJECTS: Athletic men and women from the French West Indies showing no anemia and/or alpha thalassemia. METHODS: Anemia was ruled out by hemoglobin ...
Xu Jianguo - - 2003
PURPOSE: To evaluate the effects of fresh lime, lemon, grapefruit, and pummelo juices on the transport of digoxin, a P-glycoprotein (P-gp) substrate, in Caco-2 cell monolayers. METHODS: Bidirectional [3H]-digoxin fluxes across confluent Caco-2 cell monolayers were determined in 0-50% fruit juices at pH 7.4. Verapamil HCl (100 microM) served as ...
Wells R M G - - 2003
Tarpon have high resting or routine hematocrits (Hct) (37.6+/-3.4%) and hemoglobin concentrations (120.6+/-7.3 gl(-1)) that increased significantly following bouts of angling-induced exercise (51.9+/-3.7% and 142.8+/-13.5 gl(-1), respectively). Strenuous exercise was accompanied by an approximately tenfold increase in blood lactate and a muscle metabolite profile indicative of a high energy demand ...
Ajmani Ranjeet S - - 2003
The present investigation was designed to evaluate the acute effect of aerobic exercise on oxidative stress and the flow properties of the blood. Fourteen clinically healthy subjects (7 men and 7 women aged 56+/-19 yr) underwent maximal treadmill exercise with blood samples drawn prior to and immediately after exercise. Post-exercise ...
Gaudard A - - 2003
Negative correlations between blood viscosity parameters and fitness have been reported, but their physiological meaning remains incompletely understood. Since rheo-active treatments are used in athletes doping, we aimed at clarifying the relationships between hematocrit (Hct), viscosity and performance by comparing aerobic capacity, overtraining questionnaire, and hemorheological parameters. SUBJECTS AND METHODS: ...
Melnikov Andrey A - - 2003
It is well established that exercise performance in athletes is related to improved blood fluidity. However, training effects on functional state of endothelium and relations of endothelial cell functions with hemorheology are poorly known. Circulating levels of von Willebrand factor may serve as a good marker of endothelial cell functions, ...
Varlet-Marie E - - 2003
Effects of exercise on erythrocyte aggregation were investigated in 19 elite athletes. High shear rate viscometry (1000 s(-1) evidenced an increase in blood viscosity explained by an increase in hematocrit (+8% p<0.01) and plasma viscosity (+7% p<0.01). Erythrocyte rigidity index and erythrocyte aggregability measured using the Myrenne erythroaggregometer did not ...
Stewart Ian B - - 2003
To investigate splenic erythrocyte volume after exercise and the effect on hematocrit- and hemoglobin-based plasma volume equations, nine men cycled at an intensity of 60% maximal O(2) uptake for 5-, 10-, or 15-min duration, followed by an incremental ride to exhaustion. The reduction in spleen volume, calculated using (99m)Tc-labeled erythrocytes, ...
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