Measurement of Water Distribution and Transcapillary Solute Flux in Dog Lung by External Radioactivity Counting

1979 ◽  
Vol 57 (2) ◽  
pp. 145-154 ◽  
Author(s):  
J. S. Prichard ◽  
G. de J. Lee

1. A method for measuring the pulmonary water compartments in vivo in anaesthetized dogs is described. 2. The technique depends upon the sequential intravenous injection of markers labelled with γ-ray-emitting isotopes. Each is allowed to become evenly distributed throughout the compartment to which it is confined. A calibrated γ-counter placed at the surface of the inflated lung then records a count rate related to the total quantity of isotope in unit volume of tissue. The size of each water compartment can be calculated from the external count rate and the isotopic concentration of the marker in plasma. 3. The markers used were 125I-labelled serum albumin for plasma, [125I]iodide for extracellular water and [125I]iodoantipyrine for total water. 4. The method was extended to calculate transcapillary flux rates of serum albumin and showed that rapid exchange of serum albumin takes place between the plasma and interstitial space. 5. Results obtained non-invasively by the isotopic method were compared with direct measurements. Agreement was good.

2021 ◽  
Author(s):  
Chao Zhang ◽  
Xusheng Guo ◽  
Xuwen Da ◽  
Yishan Yao ◽  
Haihua Xiao ◽  
...  

Ru(II)-based photoactivated chemotherapy (PACT) agents are promising, however, the short wavelength absorption (generally < 550 nm) and poor tumor accumulation ability limit their in vivo applications. Herein bovine serum albumin...


Blood ◽  
1993 ◽  
Vol 82 (11) ◽  
pp. 3460-3468 ◽  
Author(s):  
YP Rochon ◽  
MM Frojmovic

Abstract We have recently described a flow cytometry technique, whose sensitivity allows direct measurements of latent times before the onset of aggregation, and of rates, maximal extents, and reversibility of aggregation (J Leuk Biol 50:434, 1991). We report here that activators which stimulate sustained cellular signaling associated with increases in intracellular calcium (ionomycin) or protein kinase C activation (phorbol myristate acetate, PMA) cause complete (> or = 98%) and irreversible neutrophil aggregation, with latent times for the onset of aggregation inversely proportional to the activator concentration. In contrast, the receptor-specific activators leukotriene B4 (LTB4), formyl peptide FMLP, and platelet-activating factor (PAF) gave only partial and reversible aggregatory responses, limited by the following similar properties: latent times of 4.5 seconds +/- 1.5 seconds, independent of activator concentration; similar concentrations for onset of aggregation (approximately 1 nmol/L) that increased over a similar broad range of activator concentration, with one-half maximal rates of aggregation at 10 nmol/L to 30 nmol/L, corresponding to reported dissociation constant values; comparable limited recruitment and spontaneous reversibility of aggregation; absence of interactivator synergism; and similar exponential decays in activated cell stickiness (refractoriness), with t1/2 = 15 to 30 seconds. Variable cross- desensitization was seen between LTB4 and FMLP depending on donor and activator concentrations. In vivo, these properties are expected to provide localization of the aggregatory response, minimizing the otherwise detrimental effects of circulating activated neutrophils.


2017 ◽  
Vol 29 (12) ◽  
pp. 2301 ◽  
Author(s):  
R. H. F. Hunter ◽  
F. López-Gatius ◽  
O. López-Albors

Since 1980 several reports have indicated that temperatures vary between preovulatory follicles and other ovarian tissues in rabbit, cow, pig and human. However, these observations did not achieve prominence; they were regarded as artefacts due to the use of anaesthetics and open surgery (laparotomy). Recently, without resorting to anaesthesia or surgery, direct measurements of temperature in preovulatory follicles have been performed in the cow by means of a thermistor probe introduced into the antrum under ultrasonic guidance. Such follicles revealed a mean antral (follicular fluid) temperature 0.74°C and 1.54°C cooler than uterine surface and rectal temperatures respectively in ovulating cows, whereas no such temperature differences were detected in non-ovulating cows. Cows are predominantly monovular and preovulatory follicles attain a diameter of 15–22 mm or more. These features and the timescale of response to the preovulatory gonadotrophin surge make them a valuable model for the human preovulatory follicle. Temperature gradients are interpreted primarily in a context of final maturation of gametes immediately before the onset of fertilisation. Preovulatory follicular temperature in women could be assessed by a comparable approach and might become a valuable selection guide for oocyte viability.


1989 ◽  
Vol 257 (2) ◽  
pp. G210-G220 ◽  
Author(s):  
X. Deroubaix ◽  
T. Coche ◽  
E. Depiereux ◽  
E. Feytmans

Compartmental analysis was used to study the hepatobiliary transport of taurocholate (TC) in the rat in vivo. The available data are the following: [14C]TC kinetics in blood and bile, weighting factors associated with these data and computed from a theoretical variability model, and TC excretion rate in bile. The lumped model that best fits the data contains five compartments: three compartments for TC distribution in blood and two compartments for the liver. It includes a compartmental representation of the laminar flow of bile in the collecting catheter. This model overestimates TC concentration in blood. A perfusion model that includes a compartment representing explicitly the sinusoidal TC concentration gradient was developed. TC concentration in blood estimated by this model is in good agreement with direct measurements, showing that the perfused model has a better descriptive capacity than the lumped model. The amounts of TC estimated in the two hepatic compartments are similar to values previously published.


1993 ◽  
Vol 70 (2) ◽  
pp. 433-438 ◽  
Author(s):  
N. Battistini ◽  
F. Virgili ◽  
G. Bedogni ◽  
G. R. Gambella ◽  
A. Bini

Total body electrical conductivity (TOBEC) is a simple and non-invasive method for the assessment of body composition in vivo. Information regarding the applicability of TOBEC in the condition of abnormal fluid balance is scarce. In the present paper we give the results of the comparison between TOBEC and total body water (TBW; assessed by the tritium dilution technique) in three groups of animals: (1) healthy (n 17), (2) expanded fluid volume by secondary biliary cirrhosis (SBC; n 9) and (3) Fiirosemide®-treated rats (n 9). The TOBEC score and TBW by tritium dilution were found to be highly correlated in the pooled sample (r 0·90) and in normal (r 0.·87), SBC (r 0·73) and Furosemide-treated (r 0·89) rats. However, the relationship between TOBEC and TBW, described by least-squares regression analysis, was found to be similar for SBC and normal rats but was significantly different for Furosemide-treated and normal rats. These findings suggest that TOBEC is unable to track TBW accurately when the ratio between intracellular and extracellular water is chronically or acutely altered.


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