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Spontaneous and induced chemiluminescence of rat blood plasma following irradiation of the animals with fast neurons was studied. Dynamics of the luminescence reflected the degree of radiation injury and an oscillatory response of blood chemiluminescent effect was observed.
To check the proposed hypothesis that the relative content of individual polyunsaturated fatty acids (PUFAs)--substrates and inhibitors of prostanoid synthesis--in plasma can be regarded as a quantitative risk factor of blood clotting, a test was conducted on free fatty acids content in blood plasma of healthy people (group 0) and patients with heart ischemia before (group 1) and after (group 2) they were treated for a month with a food additive called "Eiconol," enriched with PUFA omega 3. Different proportions of PUFAs have been calculated in all cases, accounting for the contribution of each acid to the process of primary clotting. Comparison of PUFA rations among the three groups showed significant differences of means between groups 0 and 1 and also group 1 and 2 for 6 out of 7 proposed coefficients, which disappeared after "Eiconol" treatment (comparison of groups 0 and 2). The results led to the conclusion that out of the proposed PUFA proportions, the coefficients describing the relative content of arachidonic acid in blood plasma may be the most informative for diagnosis and treatment efficiently in evaluation of heart and vascular diseases.
As an extension of previous work, a microfluidic device, which can separate blood plasma in a continuous, real-time fashion from a whole blood, is successfully integrated with a mock cardiopulmonary bypass circuit. The functionality of the device is demonstrated with the use of freshly harvested bovine blood. The plasma selectivities were 100% and 99.4% and the plasma separation volume percents were 18.7% and 24.5% for 26% and 37% inlet hematocrit levels, respectively. As an advanced stage of this research, a microfluidic device, which can measure the concentration of clinically relevant blood plasma protein in a continuous fashion, is being developed on the basis of fluid handling circuits coupled to fluorescent cytometric bead assays. The functionality of the device is demonstrated with the use of a biotinylated FITC solution and a streptavidin-coated, 8-mum-diameter bead. The binding event between biotinylated FITC and the streptavidin bead is continuously detected within a detection window at the outlet of the device. For a known concentration (1 microg/ml) of biotinylated FITC solution, the measured fluorescent intensity is fairly constant and shows a stable gaussian distribution of the bead fluorescence intensity. It is expected that the proposed device can be used for continuous measurement of clinically relevant proteins during cardiac surgery with the cardiopulmonary bypass procedure.
A quantitative procedure for estimation of retinol in human blood plasma using high pressure liquid chromatography involved separation of the retinoids on an reversed phase analytical column. C19-retinoid aldehyde was used as an internal standard. The procedure enabled to detect up to 0.015 microgram of retinol/ml of blood plasma and may be used for routine clinical analyses.
Mean concentration of total cholesterol, measured in 156 samples of cord blood plasma, determined according to the method of Huang et al. was 70.5 mg./dl. (SD +/- 14.7). This value is comparable to that obtained by other authors in different countries. Concentration of cholesterol corresponding to the high density lipoprotein (HDL) was measured by precipitating with Heparin and Mn++, in 141 samples of cord blood plasma. Mean concentration was 31.2 mg. of HDL-cholesterol per dl of plasma (SD +/- 9.0). This value represents 45.5% (SD +/- 13.0) of total cholesterol, and it is also similar to that reported by others. These results indicate, therefore, that total cholesterol concentration and its distribution among the lipoprotein fractions are practically the same for all the population samples so far examined.
Blood plasma, serum and its fractions containing components of different molecular masses obtained by dialysis and gradual ultrafiltration were tested for their action on the sodium currents of voltage clamped internally perfused neuroblastoma cells. Blood plasma free of platelet factor 4, serum and its fractions containing components of molecular masses more than 50 kD produced an increase in sodium channel currents and shifts in activation and inactivation curves along the voltage axis towards more negative or positive potentials, respectively. Moreover, the serum deficient in components with the molecular masses less than 50 kD produced a more prominent effect on all the parameters tested. Thus, the low-molecular fractions were suggested to exert an inhibitory activity on the stimulatory effects produced by the high-molecular components of the serum.
Lipoproteins were isolated from adult plasma and the umbilical cord blood plasma of newborn infants and were compared for their capacity to inhibit mitogen-stimulated [3H]thymidine uptake of adult peripheral blood mononuclear cells in vitro. Relative to the comparable adult lipoproteins, cord blood low density lipoproteins and high density lipoproteins inhibited mitogen stimulation at twofold to fourfold lower total protein concentrations. Apoproteins AI, B, and E were quantitated by radioimmunoassay of each of the adult and cord blood lipoprotein fractions. A strong correlation was observed between inhibitory activity and the amount of apoprotein E in the cord blood low and high density lipoproteins. Further evidence that lipoproteins containing apoprotein E accounted for the difference in suppressive activity of cord blood low and high density lipoproteins relative to the adult lipoproteins was obtained by selective removal of the apoprotein E-containing lipoproteins by using immunoaffinity chromatography or heparin-agarose adsorption. The results indicated that cord blood lipoproteins containing apoprotein E in association with apoproteins AI or B are capable of suppressing lymphocyte proliferation in vitro.
The graft copolymer poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) and its RGD- and RDG-functionalized derivatives (PLL-g-PEG/PEG-peptide) were assembled from aqueous solutions on titanium (oxide) surfaces. The polymers were characterized by NMR in order to determine quantitatively the grafting ratio, g (Lys monomer units/PEG side chains), and the fraction of the PEG side chains carrying the terminal peptide group. The titanium surfaces modified with the polymeric monomolecular adlayers were exposed to full heparinized blood plasma. The adsorbed masses were measured by in situ ellipsometry. The different PLL-g-PEG-coated surfaces showed, within the detection limit of the ellipsometric technique, no statistically significant protein adsorption during exposure to plasma for 30 min at 22 degrees C or 37 degrees C, whereas clean, uncoated titanium surfaces adsorbed approximately 350 ng/cm2 of plasma proteins. The high degree of resistance of the PEGylated surface to non-specific adsorption makes peptide-modified PLL-g-PEG a useful candidate for the surface modification of biomedical devices such as implants that are capable of eliciting specific interactions with integrin-type cell receptors even in the presence of full blood plasma. The results refer to short-term blood plasma exposure that cannot be extrapolated a priori to long-term clinical performance.
Average sorbite half-life values were 11.8 minutes in two fasting calves, 18.7 minutes in three calves after drinking, 16.4 minutes in five heads of young cattle, and 16.6 minutes in two heads of adult cattle, following intravenous injection of 0.5 g/kg live weight of sorbite solution. Sorbite conversion thus proved adequate and better than glucose conversion. Fructose levels in the blood plasma of fasting calves as well as of young and adult cattle underwent statistically significant rises, following sorbite infusion, the steepest rise being recorded from adult cattle. Significant glucose and insulin increases following sorbite infusion were recordable only from blood plasma of adult cattle. Concentrations of free fatty acids in blood plasma were quite irregular.
Many disease states have associated blood viscosity changes. Molecular rotors, fluorescent molecules with viscosity sensitive quantum yields, have recently been investigated as a new method for biofluid viscosity measurement. Current viscometer measurements are complicated by proteins adhering to surfaces and forming air-surface layers. It is unknown at this time what effects proteins may have on biofluid viscosity measurements using molecular rotors. To answer this question, binding affinities to blood plasma proteins were investigated by equilibrium dialysis for four hydrophilic molecular rotors. Aqueous solutions of 9-[(2-cyano-2-hydroxy-carbonyl)vinyl]julolidine (CCVJ) and three derivatives were prepared and dialyzed against solutions of bovine source albumin, fibrinogen and immunoglobulin G approximating normal physiologic concentrations and fresh-frozen human plasma. After equilibration, dye concentration on each side of the dialysis membrane was assessed by spectrophotometry. The relative binding affinity of the four dyes to the proteins and to the plasma was compared. Affinity of all dyes was highest for albumin. The bound dye fraction showed little change in relation to protein concentration in the physiological concentration range. Diol, the most hydrophilic molecular rotor tested showed the lowest affinity for albumin. This study indicates that hydrophilic molecular rotors are well-suited for biofluid viscosity measurement.
A method for the delipidization of blood plasma of rabbits and dogs with diethyl ether with its subsequent reinfusion into the animal's body is described. Triglycerides and cholesterol were mainly extracted from blood plasma, and only 1/3 of phospholipids. In dog experiments the plasma delipidization procedures led to a decrease of the cholesterol content in the overall fraction of atherogenic lipoproteins of low and very low density and an increase of the cholesterol content in antiatherogenic lipoproteins of high density. The lipoextraction procedures are harmless and may be employed for reducing the blood lipid level.
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A simple and sensitive method for the determination of threonine in rat blood plasma using aldehyde dehydrogenase after oxidation with periodate was developed. By the present method, threonine could be completely discriminated from serine and determined at the nanomole level. The amount of threonine in rat blood plasma obtained by the present method coincided well with the value determined on an amino acid analyzer.
Estimates of the concentrations and identity of the predominant complexes of iron with the low-molecular-mass ligands in vivo are important to improve current understanding of the metabolism of this trace element. These estimates require a knowledge of the stability of the iron-citrate complexes. Previous studies on the equilibrium properties of the Fe(III)-citrate and Fe(II)-citrate are in disagreement. Accordingly, in this work, glass electrode potentiometric titrations have been used to re-determine the formation constants of both the Fe(III)- and Fe(II)-citrate systems at 25 degrees C in 1.00 M (Na)Cl and the reliability of these constants has been evaluated by comparing the measured and predicted redox potentials of the ternary Fe(III)-Fe(II)-citrate system. The formation constants obtained in this way were used in computer simulation models of the low-molecular-mass iron fraction in blood plasma. Redox equilibria of iron are thus included in large models of blood plasma for the first time. The results of these calculations show the predominance of Fe(II)-carbonate complexes and a significant amount of aquated Fe(II) in human blood plasma.
The distribution of LDH and CK isoenzymes in blood plasma of ten clinically sound Thoroughbreds with reasonable performance and without elevated clinico-chemical blood variables (reference group) was compared with 57 Thoroughbreds, which had histories of mild locomotor disturbances and/or poor performance and had elevated CK, LDH and/or AST activities (trial group). The trial group was subdivided according to the number of altered blood variables and in the groups with two as well as three altered blood variables also according to the extent of alteration of the total CK activity. The pattern of LDH and CK isoenzyme distribution in the blood plasma of the reference group was the following: 22% LDH1, 36% LDH2, 34% LDH3, 6% LDH4 and 2% LDH5 as well as 75% CK1 and 15% CK2. The remaining 10% of the plasma electropherogram could not be alloted to any one of the two CK bands. All trial groups built showed a similar pattern of changes in their isoenzyme distribution independent on kind and combination of altered enzyme activities. The shares of CK1, LDH4 and LDH5 were significantly increased whilst the shares of CK2, LDH1 and LDH2 decreased. A multiple analysis of variance demonstrated that only increased total CK activities had a pronounced effect on distribution of LDH and CK isoenzyme patterns in the trial group (p less than 0.01 for LDH2, LDH3, LDH4, CK1 and p less than 0.05 for CK2). The conclusion of the study was that the altered distribution pattern of LDH and CK isoenzymes of the trial group signalized an increased skeletal muscle membrane leakage.
Dynamics of hemoglobin, ceruloplasmin concentration, the changes of chemiluminescence in blood plasma and kinetics of rat erythrocyte heat denaturation during consequent exposition of high altitude hypoxia and hyperbaric oxygenation have been studied. Severe hypoxia causes the decrease of extraerythrocyte hemoglobin and oxidase activity of ceruloplasmin. Reoxygenation results in significant increase of blood plasma chemiluminescence with simultaneous increase of extraerythrocyte hemoglobin level and with modification of surface structure of the erythrocyte membranes. Possible pathways of activation of oxygen-dependent of free-radical processes during reoxygenation are discussed.
Fatty acid compositions of erythrocyte membrane phospholipids including phosphatidylethanolamine subclasses, blood plasma and mononuclear cells of 8 patients with myotonic dystrophy (MyD) and 8 normal controls were analyzed by high performance liquid chromatography. Slight changes (decreased C18:2 and increased C16:0) in the fatty acid compositions of erythrocyte membrane glycerophospholipids and blood plasma lipids were observed in MyD. There was no significant difference in the fatty acid composition of mononuclear cells between MyD and normal controls. It seems that no essential defect exists in either the erythrocyte membrane fatty acid composition or the fatty acid metabolism itself in MyD.
A phospholipase A2 (PLA2) inhibitor was purified from the blood plasma of a sea krait, Laticauda semifasciata, by sequential chromatography on Sephadex G-200, Mono Q, and Phenyl Sepharose columns. The purified inhibitor was found to be the same type as the PLA2 inhibitors, named PLIgamma, that had been purified from the blood plasma of the Thai cobra Naja naja kaouthia [Ohkura et al. (1994) Biochem. Biophys. Res. Commun. 200, 784-788] and Chinese mamushi Agkistrodon blomhoffii siniticus [Ohkura et al. (1997) Biochem. J. 325, 527-531]. Like other PLIgammas, the L. semifasciata inhibitor (LsPLIgamma) inhibited equally all of the PLA2s investigated including Elapid venom PLA2s (group I), Crotalid and Viperid venom PLA2s (group II), and honeybee PLA2 (group III). The LsPLIgamma was a 100-kDa glycoprotein composed of two distinct subunits, LsPLIgamma-A and LsPLIgamma-B, with an approximate molar ratio of 2:1. The amino acid sequences of the two subunits were determined by alignment of the peptides obtained by lysyl endopeptidase, endoproteinase Asp-N, and staphylococcal V8 protease digestions. LsPLIgamma-A and LsPLIgamma-B were composed of 182 and 181 amino acid residues, respectively; and the former subunit was a glycoprotein containing one asparagine-linked sugar chain at the position 157. The sequences of LsPLIgamma-A and LsPLIgamma-B showed 65 and 74% homology, respectively, to those of the corresponding subunits of N. naja kaouthia PLIgamma, and had two tandem patterns of cysteine residues, characteristic of the urokinase-type plasminogen activator receptor (uPAR) and members of the Ly-6 superfamily.