scholarly journals Clinically Significant Effect of Protein Concentration on Ion-Selective Electrode Measurements of Ionised Calcium

1982 ◽  
Vol 19 (4) ◽  
pp. 233-237 ◽  
Author(s):  
R B Payne
Keyword(s):  
Plasma Proteins ◽  
Protein Concentration ◽  
Calcium Concentration ◽  
Human Albumin ◽  
Albumin Concentration ◽  
Selective Electrode ◽  
Serum Samples ◽  
Ionised Calcium ◽  
Clinically Significant ◽  
Positive Interference

Others, using an Orion SS-20 ionised calcium analyser, noted that the ionised calcium concentration of a native serum sample was 8% greater than that of its ultrafiltrate. The experiments described here, using a Nova 2 ionised calcium analyser, confirmed a positive protein interference which was greater for human albumin than for IgG. Uncharged dextran showed no positive interference but dextran sulphate, which is highly charged and binds calcium, showed a large effect. Thus the interference is related to macromolecule charge. Dialysis experiments with normal and pathological human serum samples indicated that the ionised calcium of diffusible plasma water was overestimated by an average of 9 · 6% at an albumin concentration of 40 g/l and by 4 · 8 % at 20 g/l. It is concluded that the measurement of ionised calcium with existing analysers can be clinically misleading in patients with abnormal plasma proteins. Hypocalcaemia is likely to be overdiagnosed and hypercalcaemia underdiagnosed in the presence of hypoalbuminaemia.

scholarly journals Protein Interferes with Ionised Calcium Measurement at the Reference Electrode Liquid Junction

1987 ◽  
Vol 24 (4) ◽  
pp. 400-407 ◽  
Author(s):  
R B Payne ◽  
D P Jones
Keyword(s):  
Protein Concentration ◽  
Calcium Concentration ◽  
Reference Electrode ◽  
Liquid Junction ◽  
Human Control ◽  
Control Serum ◽  
Ionised Calcium ◽  
Clinically Significant ◽  
Calcium Measurement ◽  
Junction Potential

The ionised calcium concentration of sequential retentates prepared by ultrafiltration of a human control serum increased with increasing protein concentration when measured with both a Nova 2 and a Radiometer ICA1 analyser using their standard reference electrodes. In contrast, the ionised calcium in the same retentates fell slightly with increasing protein when the reference electrode liquid junctions of the instruments were changed from hypertonic to isotonic solutions, the values then paralleling those in the filtrates. Thus, the clinically significant positive relationship between ionised calcium and protein that has been reported with the Nova 2 and ICA1 analysers is almost certainly an effect of protein on the reference electrode liquid junction potential rather than a consequence of a Donnan effect on true ionised calcium distribution.

Effect of pH and storage conditions on measured ionised calcium concentration in dogs and cats

2020 ◽  
Vol 187 (9) ◽  
pp. e72-e72
Author(s):  
Michal Mazaki-Tovi ◽  
Shira Topol ◽  
Itamar Aroch
Keyword(s):  
Calcium Concentration ◽  
Storage Conditions ◽  
Sample Collection ◽  
Serum Samples ◽  
Aerobic Conditions ◽  
Effect Of Ph ◽  
Ionised Calcium ◽  
Clinically Significant ◽  
And Storage ◽  
Good Agreement

BackgroundAerobic blood sample collection and processing results in increased serum pH and decreased ionised calcium (iCa) concentration. This prospective study aimed to determine the effect of pH and storage conditions on measured iCa concentration in serum samples obtained from dogs and cats and establish correction formulas for use in samples obtained aerobically.MethodsBlood samples were collected from 44 dogs and 25 cats; iCa and pH were measured immediately under anaerobic conditions and in samples stored under several aerobic conditions.ResultsMeasured iCa concentrations were significantly lower in samples stored at all aerobic conditions than in samples handled anaerobically in both dogs and cats (P<0.01 for all). The largest and most clinically significant differences were noted in samples stored at −20°C for 30 days in both dogs (0.48 mmol/l; 95 per cent CI 0.40 to 0.55) and cats (0.40 mmol/l; 95 per cent CI 0.33 to 0.47). Correction formulas (corrected iCa=measured iCa+coefficient × (measured pH–7.41); coefficient=0.597 for dogs, 0.627 for cats) yielded good agreement between the corrected and the actual iCa concentrations.ConclusionsSamples for iCa measurement can be stored at either 4°C or −20°C for 24 hours. Storage at −80°C is recommended for longer storage time periods.

Binding of calcium by human plasma proteins under simulated physiologic conditions

1964 ◽  
Vol 19 (2) ◽  
pp. 292-296 ◽  
Author(s):  
Irene R. Held ◽  
Smith Freeman
Keyword(s):  
Human Plasma ◽  
Plasma Proteins ◽  
Protein Concentration ◽  
Calcium Concentration ◽  
Gamma Globulin ◽  
Chloride Concentration ◽  
Total Calcium ◽  
Total Protein Concentration ◽  
Plasma Albumin

The binding of calcium to human plasma albumin, alpha, beta, and gamma globulins was studied with the aid of an ultracentrifuge. The amount of calcium bound to these separated proteins was determined in solutions with electrolyte concentrations and pH within physiological ranges. The total calcium concentration was 2.35–2.90 mm/liter H2O and the total protein concentration was 3.91–4.29 g/100 ml H2O. In these solutions no significant differences were found for the binding of calcium (expressed as mm Ca++ bound per gram protein) by albumin, alpha, and beta globulins; the average values obtained were, respectively, 0.016, 0.018, and 0.023. Significantly less calcium was bound by gamma globulin; 0.009 mm/gram. The pH was varied between 7.200–7.550 and the sodium chloride concentration between 114–157 mEq Na per liter. These changes did not measurably affect the amount of calcium bound to albumin. protein-bound calcium; ultracentrifugation and determination of protein-bound calcium; plasma globulin-bound calcium; plasma albumin-bound calcium Submitted on July 2, 1963

Determination of ionised calcium by ion selective electrode is not independent of albumin concentration

1986 ◽  
Vol 158 (2) ◽  
pp. 129-137 ◽  
Author(s):  
R. Freaney ◽  
T. Egan ◽  
M.J. McKenna ◽  
M.C. Doolin ◽  
F.P. Muldowney
Keyword(s):  
Ion Selective Electrode ◽  
Albumin Concentration ◽  
Selective Electrode ◽  
Ionised Calcium

scholarly journals STUDIES ON THE CONGLUTINATION REACTION, WITH SPECIAL REFERENCE TO THE NATURE OF CONGLUTININ

1947 ◽  
Vol 86 (4) ◽  
pp. 267-284 ◽  
Author(s):  
Alexander S. Wiener ◽  
Jane G. Hurst ◽  
Eve B. Sonn-Gordon
Keyword(s):  
Immune Globulin ◽  
Total Protein ◽  
Plasma Proteins ◽  
Protein Concentration ◽  
Human Albumin ◽  
Specific Adsorption ◽  
Albumin Solution ◽  
X Protein ◽  
Cent Concentration ◽  
Human Albumin Solution

1. Dilution of pooled plasma with more than an equal volume of saline solution destroys its ability to produce conglutination of red cells sensitized by univalent antibody. This can be correlated with Pedersen's work showing that X-protein is readily dissociated by dilution. The observation explains the discrepancy between the reports of British and American workers regarding the incidence of Rh "agglutinins" in the serum of Rh-negative mothers of erythroblastotic babies. 2. Plasma has a higher conglutinating activity than serum as shown by the finding that plasma gives titers on the average more than twice as high as those obtained with serum. The greater activity of plasma would seem due to the presence of fibrinogen which is apparently an important component of the colloidal complex of plasma proteins making up conglutinin. 3. Aside from its action in precipitating fibrinogen, heating at 56°C. for onehalf hour has no harmful effect on conglutinin. 4. Fetal plasma and serum yield much lower conglutination titers than adult plasma and serum, indicating that fetal blood is deficient in conglutinin. After birth, there is generally a marked increase in the conglutinin content of the blood. There is little or no variation in the conglutinin activity of sera from different normal adult individuals. 5. The use of whole citrated blood in exchange transfusion to an erythroblastotic baby caused an appreciable rise in the total plasma proteins after the transfusion and a corresponding increase in the conglutinating activity. When however, in another instance, two-fifths of the plasma was removed from the donor's blood and replaced with saline, there was no appreciable change in the protein concentration or conglutinin activity of the infant's plasma after the transfusion. 6. The fortification of pooled plasma by mixing 4 parts of it with 1 part of 25 per cent human albumin solution markedly increased its conglutinin content as shown by a fourfold increase in the conglutination titers obtained. Addition of less or more than this optimal amount of albumin resulted in lower titers. The 25 per cent human albumin solution itself yielded titers only half as high as did unmodified pooled plasma and was difficult to work with because of its high viscosity. Similar results were obtained in experiments with immune globulin solutions and pooled plasma. 7. Albumin solutions of less than 12.5 per cent concentration had little or no conglutinin activity; similarly, immune globulin solutions of less than 4.6 per cent concentration gave only relatively low titers when used as conglutinin. Yet, mixtures of these dilute solutions in certain optimal proportions yielded solutions with conglutinin activities considerably higher than that of pooled plasma. The albumin-globulin ratio in the mixtures giving the best results proved to be approximately the same as the albumin-globulin ratio of normal human serum or plasma. 8. Suitable mixtures of albumin and globulin solutions with a total protein concentration equal to that of normal plasma gave conglutination titers about four times as high as those obtained with unmodified pooled plasma. This suggests that there may be substances in normal plasma which tend to maintain the albumin and globulin in molecular dispersion. Another possibility is that in the fractionation process the albumin and globulin are rendered less hydrophilic, thus increasing their tendency to form colloidal aggregates. 9. The experiments described support the theory that clumping of cells by univalent antibodies in plasma media occurs in two stages, namely, (1) specific adsorption of univalent antibodies, and (2) non-specific adsorption of conglutinin by the sensitized cells causing them to stick together. The experiments further support the concept of conglutinin or X-protein as a colloidal aggregate of plasma proteins. Finally, they demonstrate that the intensity of the clumping (conglutination—not agglutination) depends on the quantity and quality of conglutinin and not merely on the total protein content of the medium of suspension.

Acid-base effects of altering plasma protein concentration in human blood in vitro

1986 ◽  
Vol 61 (6) ◽  
pp. 2260-2265 ◽  
Author(s):  
T. H. Rossing ◽  
N. Maffeo ◽  
V. Fencl
Keyword(s):  
Plasma Protein ◽  
Human Blood ◽  
Plasma Proteins ◽  
Protein Concentration ◽  
Albumin Concentration ◽  
High Concentration ◽  
Acid Base ◽  
Plasma Protein Concentration ◽  
Minor Variation

We altered the concentration of plasma proteins in human blood in vitro by adding solutions with [Na+], [K+], and [Cl-] resembling those in normal blood plasma, either protein-free or with a high concentration of human albumin. After equilibrating the samples with a gas containing 5% CO2-12% O2–83% N2 at 37 degrees C, we measured pH, PCO2, and PO2; in separated plasma, we determined the concentrations of total plasma proteins and albumin and of the completely dissociated electrolytes (strong cations Na+, K+, Mg2+ and anions Cl-, citrate3-). With PCO2 nearly constant (mean = 35.5 Torr; coefficient of variation = 0.02), lowering plasma protein concentration produced a metabolic alkalosis, whereas increasing plasma albumin concentration gave rise to a metabolic acidosis. These acid-base disturbances occurred independently of a minor variation in the balance between the sums of strong cations and anions. We quantified the dependence of several acid-base variables in plasma on albumin (or total protein) concentration. Normal plasma proteins are weak nonvolatile acids. Although their concentration is not regulated as part of acid-base homeostasis, hypoproteinemia and hyperalbuminemia per se produce alkalosis and acidosis, respectively.

Treatment of Hemophilia A with a Highly Purified Factor VIII Concentrate Prepared by Anti-FVIIIc Immunoaffinity Chromatography

1992 ◽  
Vol 67 (01) ◽  
pp. 019-027 ◽  
Author(s):  
Joseph E Addiego ◽  
Edward Gomperts ◽  
Liu Shu-Len ◽  
Patricia Bailey ◽  
Suzanne G Courter ◽  
...  
Keyword(s):  
Factor Viii ◽  
Hemophilia A ◽  
Virus Transmission ◽  
Human Albumin ◽  
Immunoaffinity Chromatography ◽  
Exchange Chromatography ◽  
Pharmacokinetic Studies ◽  
Enveloped Viruses ◽  
Clinically Significant ◽  
Detergent Mixture

SummaryTo reduce the risk of pathogenic virus transmission associated with the therapeutic administration of plasma-derived antihemophilic factor (FVIIIc), a process utilizing anti-FVIIIc immunoaffinity chromatography to isolate FVIIIc has been developed. In addition, the starting cryoprecipitate solution has been treated with an organic solvent/detergent mixture to inactivate lipid-enveloped viruses. A final ion exchange chromatography step is used to further remove contaminants, e.g., anti-FVIIIc antibody, potentially leached with FVIIIc during the immunoaffinity step. The purified FVTII is stabilized for lyophili-zation and storage by the addition of human albumin. The monoclonal anti-FVIIIc antibody used in the immunoaffinity step of the process is not detectable in the final preparation. Viral reduction studies performed at specific steps of the process demonstrate that 11 logs of human immunodeficiency virus (HIV) and greater than 4-5 logs of other lipid-enveloped viruses are inactivated within the first 30 s of exposure to the solvent/ detergent mixture and 4-5 logs of various model viruses, e. g. Endomyocarditis virus (EMC), are physically removed during washing of the immunoaffinity column. The lyophilized product is reconstituted using sterile water in a matter of seconds.The pharmacokinetics of Hemofil® M were compared to those obtained using a standard heat-treated concentrate (Hemofil® CT) in five severe factor VIII deficient hemophiliacs in a randomized, cross-over study. No statistically significant differences were observed in mean half life (p >0.6) or median recovery (p = 0.4) between the two preparations. No clinically significant adverse effects were observed in patients receiving either FVIII preparation.In addition, 43 patients at 18 different centers underwent pharmacokinetic studies, with a nominal dose of 50 u/kg FVIIIc Hemofil® M. The mean recovery was 103.6%, and the t 1/2 was 14.6 h. The recovery of FVIII in this group was as expected, providing an increase of assayed FVIII of approximately 2% per unit of FVTII/kg infused.Clinical trials using Hemofil® M have been initiated in 124 hemophilia A patients. The safety and efficacy of Hemofil® M has been established. To date, 0 of 60 patients tested have seroconverted to HIV. None of the previously untreated patients show clinical or laboratory evidence of Non-A, Non-B hepatitis (NANB), with 21 patients remaining negative as far as presence of antibodies to the Hepatitis C virus (a-HCV negative) at least 6 months after the initial infusion. There is no evidence of neoantigenicity, evidenced by seroconversion to murine antibody. An 8.7% (2 of 23) prevalence of anti-FVIIIc inhibitor development has been observed in previously untreated patients with FVIIIc⩽3%, receiving only the monoclonally purified solvent/ detergent treated FVIII concentrate while on study and on poststudy surveillance. All patients demonstrated clinical hemostasis following product use for either on demand bleeding or surgical prophylaxis.

Immunologic Assessment of Patients Treated with Bovine Fibrin as a Hemostatic Agent

1996 ◽  
Vol 76 (06) ◽  
pp. 0925-0931 ◽  
Author(s):  
John F Carroll ◽  
Keith A Moskowitz ◽  
Niloo M Edwards ◽  
Thomas J Hickey ◽  
Eric A Rose ◽  
...  
Keyword(s):  
Coagulation Factors ◽  
Allergic Reactions ◽  
Factor V ◽  
Normal Range ◽  
Serum Samples ◽  
Human Fibrinogen ◽  
Bovine Thrombin ◽  
Thrombotic Complications ◽  
The Mean ◽  
Clinically Significant

SummaryTwenty-one cardiothoracic surgical patients have been treated with fibrin as a topical hemostatic/sealing agent, prepared from bovine fibrinogen clotted with bovine thrombin. Serum samples have been collected before treatment with fibrin and postoperatively between 1 and 9 days, 3 and 12 weeks, and 6 and 8 months. The titers of anti-bovine fibrinogen antibodies, measured by ELISA specific for immunoglobulins IgG or IgM, increased to maximal values after about 8 or 6 weeks, respectively. After 8 months, IgG titers were on average 20-fold lower than the mean maximal value, while IgM titers returned to the normal range. IgG was the predominant anti-bovine fibrinogen immunoglobulin as documented by ELISA, affinity chromatography and electrophoresis. Anti-bovine fibrinogen antibodies present in patients reacted readily with bovine fibrinogen, but did not cross-react with human fibrinogen as measured by ELISA or by immunoelectrophoresis. A significant amount of antibodies against bovine thrombin and factor V has been found, many cross-reacting with the human counterparts. No hemorrhagic or thrombotic complications, or clinically significant allergic reactions, occurred in any patient, in spite of antibody presence against some bovine and human coagulation factors. The treatment of patients with bovine fibrin, without induction of immunologic response against human fibrinogen, appeared to be an effective topical hemostatic/sealing measure.

Fibrin Polymerization Defect in HIV-infected Patients-Evidence for a Critical Role of Albumin in the Prolongation of Thrombin and Reptilase Clotting Times

1995 ◽  
Vol 73 (03) ◽  
pp. 349-355 ◽  
Author(s):  
Pierre Toulon ◽  
Elyane Frere ◽  
Claude Bachmeyer ◽  
Nathalie Candia ◽  
Philippe Blanche ◽  
...  
Keyword(s):  
Critical Role ◽  
Human Albumin ◽  
Albumin Level ◽  
Final Concentration ◽  
Albumin Concentration ◽  
Clotting Time ◽  
Fibrin Polymerization ◽  
Small Series ◽  
Group 1

SummaryThrombin clotting time (TCT) and reptilase clotting time (RCT) were found significantly prolonged in a series of 72 HIV-infected patients drawn for routine coagulation testing. Both TCT and RCT were highly significantly correlated with albumin (r = -0.64, and r = -0.73 respectively, p<0.0001). TCT and RCT were significantly higher (p<0.0001) in a series of 30 other HIV-infected patients selected on their albumin level below 30.0 g/l (group l) than in 30 HIV-infected patients with albumin level above 40.0 g/l or in 30 HIV-negative controls; the two latter groups were not different. In vitro supplementation of plasma from group 1 patients with purified human albumin up to 45.0 g/l (final concentration) lead to a dramatic shortening effect on both TCT and RCT, which reached normal values. The TCT and RCT of the purified fibrinogen solutions (2.0 g/l final concentration) were not different in the three groups, and normal polymerization curves were obtained in all cases. This further ruled out the presence of any dysfibrinogenemia in the plasma from group 1 patients. Using purified proteins, highly significant correlations were demonstrated between the albumin concentration and the prolongations of both TCT and RCT, which were of the same magnitude order than those found in the patients plasma. These results suggest that hypo-albuminemia is responsible for the acquired fibrin polymerization defect reported in HIV-infected patients. The pathophysiological implication of the low albumin levels was suggested by the finding of decreased albumin levels (associated with prolonged TCT and RCT) in a small series of the eight HIV-infected patients who developed thrombotic complications.

scholarly journals 25-Hydroxycholecalciferol Concentration Is Associated with Protein Loss and Serum Albumin Level during the Acute Phase of Burn Injury

Nutrients ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2780
Author(s):  
Andrzej Krajewski ◽  
Krzysztof Piorun ◽  
Dominika Maciejewska-Markiewicz ◽  
Marta Markowska ◽  
Karolina Skonieczna-Żydecka ◽  
...  
Keyword(s):  
Vitamin D ◽  
Protein Concentration ◽  
Serum Albumin Level ◽  
Burn Injury ◽  
Albumin Level ◽  
Albumin Concentration ◽  
Transaminase Activity ◽  
C Reactive Protein ◽  
Reactive Protein ◽  
25 Hydroxycholecalciferol

Background: Burned patients have an increased need for vitamin D supply related to the maintenance of calcium–phosphate homeostasis and the regulation of cell proliferation/differentiation. This study aimed to analyze the concentration of 25-hydroxycholecalciferol and its relationship with severe condition after burn injury. Methods: 126 patients were enrolled in the study. Patients were qualified due to thermal burns—over 10% of total body surface area. On the day of admission, the following parameters were assessed: 25-hydroxycholecalciferol concentration, total protein concentration, albumin concentration, aspartate transaminase activity, alanine transaminase activity, albumin concentration, creatinine concentration, c-reactive protein concentration, procalcitonin concentration, and interleukin-6 concentration. Results: Almost all patients (92%) in the study group had an improper level of vitamin D (<30 ng/mL), with the average of 11.6 ± 10.7 ng/mL; 17.5% of patients had levels of vitamin D below the limit of determination—under 3 ng/mL. The study showed that there are several factors which correlated with vitamin D concentration during the acute phase of burn injury, including: total protein (r = 0.42, p < 0.01), albumin, (r = 0.62, p < 0.01), percentage of body burns (r = 0.36, p < 0.05), aspartate aminotransferase (r = 0.21, p < 0.05), and c-reactive protein (r = 0.22, p < 0.05). We did not find any significant correlation between vitamin D concentration and body mass index. Conclusions: The burn injury has an enormous impact on the metabolism and the risk factors of the deficiency for the general population (BMI) have an effect on burned patients. Our study showed that concentration of 25-hydroxycholecalciferol is strongly correlated with serum albumin level, even more than total burn surface area and burn degrees as expected. We suspect that increased supplementation of vitamin D should be based on albumin level and last until albumin levels are balanced.

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