D2 18O (deuterium oxide) method for CO2 output in small mammals and economic feasibility in man

1975 ◽  
Vol 39 (4) ◽  
pp. 657-664 ◽  
Author(s):  
N. Lifson ◽  
W. S. Little ◽  
D. G. Levitt ◽  
R. M. Henderson
Keyword(s):  
Small Mammals ◽  
Deuterium Oxide ◽  
Body Water ◽  
Economic Feasibility ◽  
The Body ◽  
Doubly Labeled Water ◽  
Co2 Output ◽  
Isotopic Analyses ◽  
Human Energy ◽  
Intake Water

A test of the validity of the isotopic steady state relationships of the doubly labeled water (H2O) method has been carried out with D2 18O in small mammals (three chipmunks and one mouse). CO2 outputs calculated just from 1) the rate of water intake and 2) the ratios of the isotopic concentrations in the body water to the intake water agreed satisfactorily with observed values. Moreover, reconstructed energy and material balances agreed reasonably with similar balances reconstructed for an immediately succeeding period on the same animals studied by the previously validated decay procedure. We conclude from an error analysis that by expressing the isotopic specific activities as abundances in excess of the body water of a subject on a given regimen, the decay procedure is economically feasible in the human with available accuracy of isotopic analyses and the present cost of H2 18O. The method therefore appears to be a useful tool ready for application to the field of human energy metabolism.

scholarly journals The Use of Infrared Spectrophotometry for Measuring Body Water Spaces

1999 ◽  
Vol 45 (7) ◽  
pp. 1077-1081 ◽  
Author(s):  
Graham Jennings ◽  
Leslie Bluck ◽  
Antony Wright ◽  
Marinos Elia
Keyword(s):  
Sample Preparation ◽  
Total Body Water ◽  
Biological Fluids ◽  
Deuterium Oxide ◽  
Body Water ◽  
The Body ◽  
Infrared Spectrophotometry ◽  
Significant Difference ◽  
Total Body ◽  
Novel Algorithm

Abstract Background: The conventional method of measuring total body water by the deuterium isotope dilution method uses gas isotope ratio mass spectrometry (IRMS), which is both expensive and time-consuming. We investigated an alternative method, using Fourier transform infrared spectrophotometry (FTIR), which uses less expensive instrumentation and requires little sample preparation. Method: Total body water measurements in human subjects were made by obtaining plasma, saliva, and urine samples before and after oral dosing with 1.5 mol of deuterium oxide. The enrichments of the body fluids were determined from the FTIR spectra in the range 1800–2800 cm−1, using a novel algorithm for estimation of instrumental response, and by IRMS for comparison. Results: The CV (n = 5) for repeat determinations of deuterium oxide in biological fluids and calibrator solutions (400–1000 μmol/mol) was found to be in the range 0.1–0.9%. The use of the novel algorithm instead of the integration routines supplied with the instrument gave at least a threefold increase in precision, and there was no significant difference between the results obtained with FTIR and those obtained with IRMS. Conclusion: This improved infrared method for measuring deuterium enrichment in plasma and saliva requires no sample preparation, is rapid, and has potential value to the clinician.

CO2 Output of Mice Measured by D2O18 Under Conditions of Isotope Re-entry Into the Body

1958 ◽  
Vol 195 (3) ◽  
pp. 721-725 ◽  
Author(s):  
Ruth McClintock ◽  
Nathan Lifson
Keyword(s):  
Material Balance ◽  
Body Water ◽  
The Body ◽  
Turnover Rates ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Co2 Output ◽  
The Difference ◽  
Isotopic Turnover ◽  
Fractional Turnover

The fractional turnover rates of the hydrogen and oxygen of the body water of mice were measured in three ways: a) by material intake, b) by material output and c) isotopically. Discrepancies occurred between the intake and output turnover rates which could be explained at least in large part by body weight changes. The isotopic turnover rates were lower than those calculated from material output. This finding is discussed in relationship to the diarrhea which the animals developed on the milk diet employed and to the circumstance that opportunity was present for isotope re-entry from excreta. The difference between the turnover rates of the oxygen and hydrogen of the body water was practically the same whether obtained isotopically or calculated from the material balance data. This probably explains the observation that the D2O18 method for calculating the total CO2 output of the mice from the difference between the isotope turnover rates gave valid results in animals in which the absolute values for the isotopic turnover rates were presumably in error.

Measurement of total energy and material balance in rats by means of doubly labeled water

1960 ◽  
Vol 199 (2) ◽  
pp. 238-242 ◽  
Author(s):  
J. S. Lee ◽  
Nathan Lifson
Keyword(s):  
Body Weight ◽  
Water Intake ◽  
Material Balance ◽  
Body Water ◽  
Doubly Labeled Water ◽  
Final Body Weight ◽  
Water Output ◽  
Isotopic Analyses ◽  
The Difference ◽  
Metabolism Chamber

A test has been carried out in rats of the possibility of measuring with the aid of doubly labeled water (D2O18) the following components of the material balance of an animal: output of CO2 and water; intake of oxygen, food and water. The items of information used for the measurement were a) isotopic analyses of initial and final blood samples, b) composition of the diet with respect to percentage protein, carbohydrate and fat, c) initial and final body weight, d) final percentage body water. Initial percentage body water obtained from a by the volume of dilution principle could substitute for d. CO2 and water output were estimated isotopically; O2 consumption, from the CO2 output and dietary R. Q.; food intake, from CO2 output and dietary composition; water intake, from the difference between water output and dietary metabolic water. A rough correction for storage of materials was made from the change in body weight. The average difference between observed values for each of the above components of the material balance and values calculated by the isotope procedure was less than 10%. The fact that dry air was supplied to the animal in the metabolism chamber used to obtain the observed values probably favored better agreement between calculated and observed values for water intake and output than would prevail in ordinary moist air.

Effect of bolus fluid intake on energy expenditure values as determined by the doubly labeled water method

1992 ◽  
Vol 72 (1) ◽  
pp. 82-86 ◽  
Author(s):  
D. Drews ◽  
T. P. Stein
Keyword(s):  
Energy Expenditure ◽  
Fluid Intake ◽  
Accurate Method ◽  
Body Water ◽  
The Body ◽  
Doubly Labeled Water ◽  
Water Sampling ◽  
Doubly Labeled Water Method ◽  
Point Determination ◽  
Source Of Error

The doubly labeled water (DLW, 2H(2)18O) method is a highly accurate method for measuring energy expenditure (EE). A possible source of error is bolus fluid intake before body water sampling. If there is bolus fluid intake immediately before body water sampling, the saliva may reflect the ingested water disproportionately, because the ingested water may not have had time to mix fully with the body water pool. To ascertain the magnitude of this problem, EE was measured over a 5-day period by the DLW method. Six subjects were dosed with 2H2(18)O. After the reference salivas for the two-point determination were obtained, subjects drank water (700–1,000 ml), and serial saliva samples were collected for the next 3 h. Expressing the postbolus saliva enrichments as a percentage of the prebolus value, we found 1) a minimum in the saliva isotopic enrichments were reached at approximately 30 min with the minimum for 2H (95.48 +/- 0.43%) being significantly lower than the minimum for 18O (97.55 +/- 0.44, P less than 0.05) and 2) EE values calculated using the postbolus isotopic enrichments are appreciably higher (19.9 +/- 7.5%) than the prebolus reference values. In conclusion, it is not advisable to collect saliva samples for DLW measurements within approximately 1 h of bolus fluid intake.

BODY COMPOSITION STUDIES ON THE SUCKLING PIG: II. THE IN-VIVO DETERMINATION OF TOTAL BODY WATER

1965 ◽  
Vol 45 (1) ◽  
pp. 14-21 ◽  
Author(s):  
T. D. D. Groves ◽  
A. J. Wood
Keyword(s):  
Body Composition ◽  
Total Body Water ◽  
Deuterium Oxide ◽  
Body Water ◽  
The Body ◽  
Total Body ◽  
Sequential Studies ◽  
Good Agreement

The method of Keston et al. (J. Biol. Chem. 122, 227) for the in-vivo determination of total body water when applied to the growing piglet has been evaluated and found to produce values in good agreement with those obtained by desiccation of the same animals.The densitometric method for the determination of deuterium oxide provides results of sufficient precision when considered in relation to the other unavoidable errors involved in work with live animals. The relative simplicity of the techniques and equipment in the present investigation recommend them for more extensive use in sequential studies of the body composition of growing animals.

scholarly journals Multi-frequency impedance for the prediction of extracellular water and total body water

1995 ◽  
Vol 73 (3) ◽  
pp. 349-358 ◽  
Author(s):  
Paul Deurenberg ◽  
Anna Tagliabue ◽  
Frans J. M. Schouten
Keyword(s):  
Total Body Water ◽  
Water Distribution ◽  
Deuterium Oxide ◽  
Body Water ◽  
The Body ◽  
Prediction Errors ◽  
Extracellular Water ◽  
Water Compartments ◽  
Measured Impedance ◽  
Total Body

The relationship between total body water (TBW) and extracellular water (ECW), measured by deuterium oxide dilution and bromide dilution respectively, and impedance and impedance index (height2/impedance) at 1, 5, 50 and 100 kHz was studied. After correction for TBW, ECW was correlated only with the impedance index at 1 and 5 kHz. After correction for ECW, TBW was best correlated with the impedance index at 100 kHz. The correlation of body-water compartments with impedance values obtained with modelling programs was lower than with measured impedance values. Prediction formulas for ECW (at 1 and 5 kHz) and TBW (at 50 and 100 kHz) were developed. The prediction errors for ECW and TBW were 1·0 and 1·7 kg respectively (coefficient of variation 5%). The residuals of both ECW and TBW were related to the ECW/TBW value. Application of the prediction formulas in a population, independently measured, revealed a slight overestimation of TBW and ECW, which could be largely explained by differences in the validation group in body-water distribution and in body builds. The ratio of impedance at 1 kHz to impedance at 100 kHz was correlated with body-water distribution (ECW/TBW). The relation is however not strong enough to be useful as a predictor. It is concluded that an independent prediction of ECW and TBW, using impedance at low and high frequency respectively, is possible, but that the bias depends on the body-water distribution and body build of the measured subject.

scholarly journals The measurement of total body water in living pigs by deuterium oxide dilution and its relation to body composition

1973 ◽  
Vol 30 (1) ◽  
pp. 149-156 ◽  
Author(s):  
R. A. Houseman ◽  
I. Mcdonald ◽  
K. Pennie
Keyword(s):  
Body Composition ◽  
Total Body Water ◽  
Deuterium Oxide ◽  
Body Water ◽  
The Body ◽  
Average Weight ◽  
The Mean ◽  
Standard Deviations ◽  
Total Body ◽  
Water Space

1. Deuterium oxide was used to estimate body water in twenty-four pigs of widely differing body composition and of average weight 83·9 kg.2. After infusion of the isotope, blood samples were collected every 30 min for 4 h. The resulting plasma was purified by a heat-distillation procedure, after which it was analysed for D2O by infrared spectroscopy.3. Approximately 24 h after infusion of the D2O each pig was killed, and its composition determined both by chemical analysis and physical dissection.4. Equilibration of D2O in the body was found to be complete within 2 h of injection of the tracer.5. The mean D2O space was found to be 8·6% greater than the mean empty body water space, but only 2·2% greater than the total body water space.6. Empty body water and total body water were estimated from the regression lines with residual standard deviations of 2·7 and 1·9% respectively. Similarly, the residual standard deviations of the regressions involving the other fat-free components were 6·3% for dissectible lean, 3·2% for fat-free mass, and 5·6% for crude protein.7. The residual standard deviations of the regressions in which the weights of dissectible fat and total body lipid were predicted were 6·0 and 6·7% respectively.

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