Oxygen Consumption In Relation Research Articles

Oxygen consumption in relation to current velocity and morphology in the highly invasive crayfish Procambarus clarkii

The red swamp crayfish (Procambarus clarkii) is the most widely spread freshwater crayfish worldwide. Competing physiological traits can influence invasion success in any given environment by limiting the available scope for aerobically demanding activities. While high flows have been associated with reduced crayfish movement upstream, the effects of flow alteration on their metabolic demands have been largely overlooked. In this study, we estimated routine metabolic rate (RMR) at rest and oxygen consumption rates of crayfish under different current velocities in a flume respirometer, while maximum metabolic rate (MMR) was determined using the exhaustive chase protocol. We also measured some morphometric variables in males and females of crayfish. Oxygen uptake substantially increased with crayfish size and current velocity due to increased energy expenditure to overcome drag and hold a stationary position. Sexual dimorphism in morphological traits did not lead to sexual differences in oxygen uptake. Moreover, we found that individuals operated close to their maximum aerobic capacity at elevated current velocities (≥ 25 cm s−1). This suggested that the high flow-driven energetic demand may compromise the energy available for reproduction, growth and dispersal, thereby affecting overall fitness. These metabolic constraints could partly explain the failed invasions of invasive crayfish in fast-flowing waters.

Oxygen consumption in relation to nitrogen metabolism in Black tiger shrimp, Penaeus monodon (Fabricius, 1798), fed fresh food and formulated feed

An indoor experiment was carried out to assess the effect of various fresh foods and formulated diets on oxygen consumption in relation to nitrogen metabolism in Penaeus monodon. Seven iso-nitrogenous diets were formulated by substituting fishmeal (w/w) at 0 (control), 2.5 and 5% using groundnut oil cake (GNC-1 and GNC-2, respectively), rapeseed meal (RSM-1and RSM-2) and sesame oil cake (SOC-1 and SOC-2). Simultaneously, five different fresh foods (clam, crustaceans, fish, polychaete and squid) were also tested. Results revealed that nitrogen intake increased (p < 0.05) by 10.5%–86.6% in shrimp fed fresh food compared with control. Among the fresh food, fish meat showed the highest (p < 0.05) oxygen consumption and ammonia-N efflux. The O:N ratio decreased by 4.22–6.62 in shrimp fed on fresh food, whereas it increased by 0.91–3.28 in formulated diets. Regression analysis revealed a higher coefficient of determination for oxygen consumption (R2 = 0.9272) as well as ammonia-N excretion (R2 = 0.8778) in fresh food compared with the formulated feeds (0.3818 and 0.2187), whereas it was found to be low for O:N ratio for both the fresh food (R2 = 0.1789) and formulated feeds (R2 = 0.3260). The results confirmed that the measurement of O:N ratio can be an additional tool for assessing the nutritional quality of feed along with growth and digestibility and was more significant with the nutritional quality of formulated diets in P. monodon over fresh foods, in relation to nitrogen metabolism.

BIMODAL OXYGEN UPTAKE OF FRESHWATER AIR-BREATHING FEATHERBACK, NOTOPTERUS NOTOPTERUS (PALLAS)

Oxygen uptake through gills and the swim bladder in relation to body weight have been measured in Notopterus notopterus at 24.5±1.0 oC, using closed glass respirometer. With increase in body weight from 4.90 to 90.00 g, the rate of oxygen uptake per unit time (ml O 2 h -1 ) increased from 1.520 to 4.113, 0.994 to 3.033 and 2.514 to 7.146 mlO 2 h -1 through air, water and air+water respectively. The slope ‘b’ of the regression line for oxygen uptake per unit time in relation to body weight from air, water and total (air+water) were found to be 0.318, 0.403 and 0.350 respectively. The relationship has been found highly significant. The weight specific oxygen consumption in relation to body weight mlO 2 kg -1 h -1 from air, water and air + water decreased from 309.750 to 45.700, 202.825 to 33.770 and 512.575 to 79.400 mlO 2 kg –1 h –1 respectively with gradual increase in the body weight from 4.90 to 90.00 g. The log-log plot between the two variables gave straight lines with the slope ‘b’ of-0.618, -0.597 and-0.649 through air, water and air+water respectively. It has been estimated that a N. notopterus having average body weight of 29.01 g, extracted about 63% of oxygen from aerial route while only 37% through its aquatic route. Key words : Air-breathing fish, Notopterus notopterus , bimodal oxygen uptake

Role of carbonic anhydrase in acute recovery following renal ischemia reperfusion injury.

Ischemia reperfusion (IR) injury can cause acute kidney injury. It has previously been reported that kidney oxygen consumption (QO2) in relation to glomerular filtration rate (GFR), and thus tubular sodium load, is markedly increased following IR injury, indicating reduced electrolyte transport efficiency. Since proximal tubular sodium reabsorption (TNa) is a major contributor to overall kidney QO2, we investigated whether inhibition of proximal tubular sodium transport through carbonic anhydrase (CA) inhibition would improve renal oxygenation following ischemia reperfusion. Anesthetized adult male Sprague Dawley rats were administered the CA inhibitor acetazolamide (50 mg/kg bolus iv), or volume-matched vehicle, and kidney function, hemodynamics and QO2 were estimated before and after 45 minutes of unilateral complete warm renal ischemia. CA inhibition per se reduced GFR (-20%) and TNa (-22%), while it increased urine flow and urinary sodium excretion (36-fold). Renal blood flow was reduced (-31%) due to increased renal vascular resistance (+37%) without affecting QO2. IR per se resulted in similar decrease in GFR and TNa, independently of CA activity. However, the QO2/TNa ratio following ischemia-reperfusion was profoundly increased in the group receiving CA inhibition, indicating a significant contribution of basal oxygen metabolism to the total kidney QO2 following inhibition of proximal tubular function after IR injury. Ischemia increased urinary excretion of kidney injury molecule-1, an effect that was unaffected by CA. In conclusion, this study demonstrates that CA inhibition further impairs renal oxygenation and does not protect tubular function in the acute phase following IR injury. Furthermore, these results indicate a major role of the proximal tubule in the acute recovery from an ischemic insult.

Physiological performance of the intertidal Manila clam (Ruditapes philippinarum) to long-term daily rhythms of air exposure

Intertidal organisms, especially the sessile species, often experience long-term periodic air exposure during their lives. Learning the biochemical and physiological responses of intertidal organisms to long-term periodic air exposure and the relationship to duration of air exposure provides insight into adaptation to this variably stressful environment. We studied the Manila clam, Ruditapes philippinarum, an important species in world aquaculture, as a model to evaluate survival, growth, lipid composition, oxygen consumption, oxidative damage, and antioxidant enzyme activity in relation to the duration of air exposure in a long-term (60 days) laboratory study of varying durations of periodic emersion and re-immersion. Our results show: (1) clams undergoing a longer period of air exposure had lower survival and growth compared to those given a shorter exposure, (2) levels of oxidative damage and activities of antioxidant enzymes were higher in all air exposure treatments, but did not increase with duration of air exposure, and (3) the content of docosahexaenoic acid increased with duration of air exposure. Our results can largely be interpreted in the context of the energy expenditure by the clams caused by aerobic metabolism during the daily cycle of emersion and re-immersion and the roles of docosahexaenoic acid against oxidative stress.

The Effect of Cadence on Shank Muscle Oxygen Consumption and Deoxygenation in Relation to Joint Specific Power and Cycling Kinematics.

The purpose of the present study was to investigate the effect of cadence on joint specific power and cycling kinematics in the ankle joint in addition to muscle oxygenation and muscle VO2 in the gastrocnemius and tibialis anterior. Thirteen cyclists cycled at a cadence of 60, 70, 80, 90, 100 and 110 rpm at a constant external work rate of 160.1 ± 21.3 W. Increasing cadence led to a decrease in ankle power in the dorsal flexion phase and to an increase in ankle joint angular velocity above 80 rpm. In addition, increasing cadence increased deoxygenation and desaturation for both the gastrocnemius and tibialis anterior muscles. Muscle VO2 increased following increased cadence but only in the tibialis anterior and only at cadences above 80 rpm, thus coinciding with the increase in ankle joint angular velocity. There was no effect of cadence in the gastrocnemius. This study demonstrates that high cadences lead to increased mVO2 in the TA muscles that cannot be explained by power in the dorsal flexion phase.

Application of cardiopulmonary exercise testing in patients with chronic thromboembolic pulmonary hypertension

To evaluate the application value of cardiopulmonary exercise testing in patients with chronic thromboembolic pulmonary hypertension (CTEPH). A total of 116 consecutive patients admitted into the Cardiology Department of Fuwai Hospital.They were divided into 3 groups of CTEPH (n = 44), CPE (without pulmonary hypertension in chronic pulmonary embolism) (n = 24) and control (without pulmonary embolism or pulmonary hypertension) (n = 48) respectively. Their levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured. Incremental cardiopulmonary exercise testing was performed to compare its differential results among 3 groups and evaluate the correlation between NT-proBNP and its parameters. The body mass index (BMI) in the CTEPH group was lower than those in the CPE and control groups ((23.8 ± 3.9) vs (26.1 ± 3.6) and (26.7 ± 3.2) kg/m(2) ), both P < 0.05); the medical history in the CTEPH group was longer than those in the CPE and control groups ((58 ± 48) vs (12 ± 10) and (29 ± 25) months, both P < 0.05). The plasma concentrations of NT-proBNP in the CTEPH group were higher than those in the CPE and control groups ((1678 ± 1255) vs (577 ± 167) and (608 ± 247) pmol/L, both P < 0.05). All of them completed the test and there were no severe complications such as syncope or exacerbation of disease. Maximum oxygen consumption (VO2max), percentage of predicted maximum oxygen consumption (VO2 %), oxygen consumption in relation to body weight (VO2/kg), anaerobic threshold and O2 pulse in the CTEPH group were significantly lower than those in the CPE and control groups (P < 0.05). The ratios of dead space volume (VD) to tidal volume (VT) in the CTEPH and CPE groups were higher than those in the control group (P < 0.05). The plasma concentrations of NT-proBNP were inversely correlated with right ventricular internal diameter (r = -0.690, P = 0.000) and VO2/kg (r = -0.496, P = 0.000). The right ventricular internal diameter (β = 0.583, P = 0.000) and VO2/kg (β = 0.233, P = 0.032) were strong independent determinants of NT-proBNP. As a reliable pathophysiological indictor of CTEPH, cardiopulmonary exercise testing may be used objectively and safely to evaluate the cardiopulmonary function of CTEPH patients.

Oxygen consumption in relation to body size, wave exposure, and cirral beat behavior in the barnacle Balanus glandula

Barnacle feeding and respiration depend on the activity of feeding appendages known as cirri. We measured the oxygen consumption of individuals of the acorn barnacle Balanus glandula Darwin, 1854 to determine how changes in beating behavior, body size, and cirrus length affected energy demand. Respiration rates increased exponentially with body mass to the 0.66 power. Respiration rates did not differ significantly among pumping, normal, and fast beats, even though these beats involve different levels of cirral and opercular activity. Finally, barnacles from a location of high water motion exhibited significantly shorter cirri and lower oxygen consumption for a given body size than those from calmer waters.

Physiological response in different strains of sea bass ( Dicentrarchus labrax): Swimming and aerobic metabolic capacities

Sea bass ( Dicentrarchus labrax) is one of the major marine species cultivated in Southern Europe. An ongoing selection programme based on production traits has produced the first generation of different strains issued from wild, domesticated or selected sires. Inter-strain differences exist upon many fish species. To test if that was the case in these strains of sea bass, we measured individual oxygen consumption (MO 2) in relation to swimming speed, critical swimming speed, standard metabolic rate, active metabolic rate, aerobic metabolic scope, net cost of transport and excess post-exercise oxygen consumption. MO 2 associated to swimming effort tended to be lower in the Wild strain, when compared to Domesticated and Selected strains. Nevertheless, no significant (p > 0.05) inter-strain differences were observed for none of the physiological traits listed above. These results suggest that (i) the selection process, based on production traits, respects functional integrity in the three strains of sea bass, and that (ii) this species possesses a large physiological plasticity. Nevertheless, before validating this selection framework, studies should be done in order to compare other genetic, physiological and behavioural traits in other strains issued from more than one generation of selection.

Effects of body weight and temperature on feed intake, gonad growth and oxygen consumption in green sea urchin, Strongylocentrotus droebachiensis

The current study describes the metabolic performance of adult green sea urchin Strongylocentrotus droebachiensis in terms of oxygen consumption, feed intake and gonad growth in relation to body weight and temperature. The experiments were conducted at six constant temperatures (4, 6, 8, 10, 12 and 14 °C), and with three body size groups, i.e. small (S, 40 g), medium (M, 65 g), and large (L, 100 g). Results show that 10–12 °C is the optimum temperature for gonad growth for 40–100-g green sea urchin during summer/autumn, and that there is an inverse relationship between optimum temperature and size. Contrary to gonad growth, both feed intake and oxygen consumption continued to increase throughout the entire temperature range (4–14 °C). The Q 10 values for oxygen consumption of fed animals were in the normal range (1.72–3.01), while the corresponding values for starved animals were low (1.17–1.36), indicating negligible effects of temperature on aerobic metabolism during starvation. The energetic analyses indicate a poorly developed regulation of energy intake in relation to energy expenditure. The oxygen consumption data from this study can, together with a still missing description of the relationship between oxygen saturation and somatic and gonad growth, be used to evaluate the water requirement of green sea urchin in aquaculture.

Knee extensor muscle oxygen consumption in relation to muscle activation

Recently, fatigability and muscle oxygen consumption (mVO(2)) during sustained isometric contractions were found to be less at shorter (30 degrees knee angle; 0 degrees = full extension) compared to longer knee extensor muscle lengths (90 degrees ) and, at low torques, less in the rectus femoris (RF) muscle than in the vastus lateralis and medialis. In the present study we hypothesized that these findings could be accounted for by a knee angle- and a muscle-dependent activation respectively. On two experimental days rectified surface EMG (rsEMG) was obtained as a measure of muscle activation in nine healthy young males. In addition, on day 1 maximal torque capacity (MTC) was carefully determined using superimposed nerve stimulation on brief high intensity contractions (> 70%MVC) at 30, 60 and 90 degrees knee angles. On day 2, subjects performed longer lasting isometric contractions (10-70%MTC) while mVO(2) was measured using near-infrared spectroscopy (NIRS). At 30 degrees , maximal mVO(2) was reached significantly later (11.0 s +/- 6.5 s) and was 57.9 +/- 8.3% less (average +/- SD, across intensities and muscles) than mVO(2) at 60 and 90 degrees (p < 0.05). However, rsEMG was on average only 18.0 +/- 11.8% (p = 0.062) less at the start of the contraction at 30 degrees . At 10%MTC at all knee angles, maximal mVO(2) of the RF occurred significantly later (28.8 +/- 36.0 s) and showed a significantly smaller increase in rsEMG compared to both vasti. In conclusion, it is unlikely that the tendency for less intense muscle activation could fully account for the approximately 60% lower oxygen consumption at 30 degrees , but the later increase in RFmVO(2) seemed to be caused by a less strong activation of the RF.

Oxygen consumption in relation to motion of marine planktonic copepods

The goal of these studies was to quantify the energy consumption of abundant marine planktonic copepods with different motion behaviors but similar body weight by determining their oxygen consumption under conditions approaching those encountered in their natural environment. The motion behaviors of adult females of the 3 copepod taxa studied ranged from the continuously fast-moving Clausocalanus furcatus to the continuously slow-moving and feeding current-producing Paracalanus aculeatus to the occasionally moving Oncaea spp. At 20°C, the daily oxygen consump- tion per unit body weight decreased significantly with decreasing activity, i.e. C. furcatus > P. aculea- tus > Oncaea spp. Expressed as percent of body carbon metabolized per day, the average values were 23.4% for C. furcatus, 15.1% for P. aculeatus, and 10.5% for Oncaea spp. Oxygen consumption of P. aculeatus and Oncaea spp. was significantly higher at 23°C than at 20°C. It is concluded that not only body weight and temperature, but also the extent of motion will affect energy expenditures of planktonic copepods.

Effects of mediators on the laccase biosensor response in paracetamol detection

An enzyme electrode suitable for paracetamol detection was developed by immobilizing laccase on a dissolved-oxygen probe surface. The immobilization procedure was achieved by means of gelatin, which was then cross-linked with glutaraldehyde. The measurement was based on the detection of oxygen consumption in relation to analyte oxidation. The optimum experimental conditions for the biosensor were investigated and the system was calibrated for paracetamol. Also the effects of three different mediators, namely HBT (1-hydroxybenzotriazole), VLA [violuric acid (5-isonitrosobarbituric acid)] and TEMPO (2,2',6,6'-tetramethylpiperidine-N-oxyl radical) were tested for the biosensor's response. As a result, it was observed that HBT has a remarkable effect on the signal by providing more oxygen consumption during the enzymatic reaction. A linear relationship between sensor responses and analyte concentrations was obtained over the concentration range 2.0-15.0 microM, whereas, in the presence of the mediator HBT, this range became 0.5-3.0 microM.

Maximal oxygen consumption in relation to subordinate traits in lines of house mice selectively bred for high voluntary wheel running

We studied relations between maximal O2 consumption (VO2 max) during forced exercise and subordinate traits associated with blood O2 transport and cellular respiration in four lines of mice selectively bred for high voluntary wheel running (S lines) and their four nonselected control (C) lines. Previously, we reported VO2 max of 59 females at three Po2 (hypoxia = 14% O2, normoxia = 21%, hyperoxia = 30%). Here, we test the hypothesis that variation in VO2 max can be explained, in part, by hemoglobin concentration and Po2 necessary to obtain 50% O2 saturation of Hb (an estimate of Hb affinity for O2) of the blood as well as citrate synthase activity and myoglobin concentration of ventricles and gastrocnemius muscle. Statistical analyses controlled for body mass, compared S and C lines, and also considered effects of the mini-muscle phenotype (present only in S lines and resulting from a Mendelian recessive allele), which reduces hindlimb muscle mass while increasing muscle mass-specific aerobic capacity. Although S lines had higher VO2 max than C, subordinate traits showed no statistical differences when the presence of the mini-muscle phenotype was controlled. However, subordinate traits did account for some of the individual variation in VO2 max. Ventricle size was a positive predictor of VO2 max at all three Po2. Blood Hb concentration was a positive predictor of VO2 max in S lines but a negative predictor in C lines, indicating that the physiological underpinnings of VO2 max have been altered by selective breeding. Mice with the mini-muscle phenotype had enlarged ventricles, with higher mass-specific citrate synthase activity and myoglobin concentration, which may account for their higher VO2 max in hypoxia.

Three Parametric Biosensor Measurement System

ABSTRACTA biosensor measurements system containing as biological element tissue from edible mushroom Agaricus bisporus for the determination of dopamine, eponephrine and norepinephrine was investigated. The measurements based on oxygen consumption in relation to analyte oxidation. The calibration graphs are linear from 2–100 μM dopamine, 5–80 μM epinephrine and 6–60 μM norepinephrine. The results obtained by the proposed enzymatic method are in close agreement with those obtained using a HPLC.

Laccase Biosensors Based on Mercury Thin Film Electrode

A biosensor was developed by immobilizing laccase onto mercury thin film electrode (MTFE) by means of gelatin that is then crosslinked with glutaraldehyde. Mercury thin film (MTF) was deposited onto glassy carbon electrode (GCE) and the obtained biosensor was utilized for the determination of phenolic compounds. The measurement was based on the amperometric detection of oxygen consumption in relation to analyte oxidation. The optimum experimental conditions for the biosensor were investigated and the system was calibrated for both catechol and phenol. A linear relationship between sensor responses and analyte concentrations was obtained in concentration range between 0.5 x 10(-6)-5.0 x 10(-6)M for catechol and 2.5 x 10(-6)-2.0 x 10(-6)M for phenol, respectively. Mercury thin film was also formed onto the surface of screen printed graphite electrodes and applied for the catechol detection. The linearity was observed in concentration range between 2.5 x 10(-6)-3.0 x 10(-5)M.

Thick film sensors based on laccases from different sources immobilized in polyaniline matrix

Thick film electrode based biosensors containing Trametes versicolor (TvL) and Aspergillus niger (AnL) laccases and Agaricus bisporus tissues (AbT) were developed for the determination of phenolic compounds and the measurement was based on oxygen consumption in relation to analyte oxidation. The electrodeposited organic polymer; polyaniline was used as a matrix for the immobilization in the preparation of thick film sensors. The systems were calibrated for different phenolic substances. A linearity was obtained in concentration range between 0.4 and 6.0 μM phenol, 0.2 and 1.0 μM catechol, 2.0 and 20.0 μM l-DOPA for TvL based biosensor; for AnL based enzyme electrode 0.4 and 4.0 μM phenol, 0.4 and 15 μM catechol, 0.4 and 6.0 μM l-DOPA; for AbT electrode 1.0 and 10 μM phenol, 0.4 and 1.6 μM catechol, 1.0 and 10 μM l-DOPA, respectively, in the response time of 300 s. Furthermore, as well as sample application and accuracy, optimum pH, temperature and thermal stabilities of the proposed systems were also detected.

Screen printed graphite biosensors based on bacterial cells

A microbial biosensor was developed for the determination of phenolic compounds and the measurement was based on oxygen consumption in relation to analyte oxidation. Induced cells of Pseudomonas putida DSM 50026 were immobilised on the surface of SPG electrodes covered with cellulose acetate membrane by means of gelatine which was then cross linked with glutaraldehyde. The systems were calibrated for different phenolic substances. Detection ranges were 0.1–1.0 μM for phenol and 0.05–1.0 μM for l-tyrosine and l-DOPA, respectively, with a response time of 3 min. Furthermore, phenol detection was performed in the presence of synthetic wastewater samples.

Effects of Worksite Physical Exercise Intervention on Physical Fitness, Perceived Health Status, and Work Ability among Home Care Workers: Five-Year Follow-up

Objective. The effects and constancy of a worksite physical exercise intervention were examined in relation to the physical fitness, perceived health status, and work ability of female service workers during periods of 1 and 5 years.Methods. The subjects comprised female home care workers divided into an intervention group (n = 50, mean age 41.8 (SD 10.4) years) and a control group (n = 37, mean age 43.3 (SD 8.8) years). The intervention group participated in 9 months of supervised exercise intervention twice a week during the workday. Functional capacity, perceived health, and work ability were assessed at the beginning of the study and after a 1- and a 5-year period of follow-up.Results. In the 1-year follow-up measurements, body fat had decreased (4%) and dynamic muscle performance and maximal oxygen consumption in relation to body mass (30–38 and 7%, respectively) had increased in the intervention group. The differences in outcome variables between the intervention and the control groups were significant (from P = 0.014 to P < 0.001). These positive effects of worksite exercise were observed despite the age of the subjects, and the changes were consistent during a 5-year period. In the control group the decline of the work ability index (L smean) was about three times faster than in the intervention group during the 5-year period.Conclusions. Physical exercise executed in work units can be used to improve the physical capacity of female home care aides and prevent the early decline of their work ability. In jobs that are physically demanding, such as home care work, early prevention must start before the age-related deterioration of health and physical capacity.

Spontaneous oscillation of oxy- and deoxy- hemoglobin changes with a phase difference throughout the occipital cortex of newborn infants observed using non-invasive optical topography.

We investigated spontaneous changes in the cerebral oxygenation state of infants during quiet sleeping by using a form of multi-channel near-infrared spectroscopy: non-invasive optical topography. Eight infants born at 32-39 weeks were studied at postconceptional term age (38-43 weeks). Spatially synchronized oscillations of changes in the concentration of oxy- and deoxy- hemoglobin ([oxy-Hb] and [deoxy-Hb]) were observed throughout the occipital cortex. Time series analysis based on the theory of non-linear oscillators showed that the mean periods of the oscillation for each infant ranged from 11 to 18 s. The phase lag of [oxy-Hb] relative to [deoxy-Hb] was stable at about 3pi/4. This phase difference may result from interplay between the vasomotion and the oxygen consumption in relation to brain activity.