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J Savory

Publications and source records attributed to J Savory.

At least 145 records · Page 8Linked to original sources
PubMed1977

Continuous-flow determination of dialyzable calcium in serum.

We describe a procedure for measuring dialyzable calcium in 60 sera per hour with use of AutoAnalyzer (Technicon) modules. The serum is buffered, then dialyzed in a regular 6-inch (15-cm) dialysis block. A constant proportion of the dialyzable calcium is fluorometrically measured. Analysis of samples containing protein, prepared by an equilibrium dialysis technique, shows that protein-bound calcium is not detected. The method requires less than 0.4 ml of serum, and is accurate, precise, and durable. No unusual care or special techniques are required during sample collection or analysis.

Adult↗
PubMed1977

Enzyme-coupled measurement of uric acid in serum with a centrifugal analyzer.

An early-reading blank-corrected end-point determination of uric acid in serum has been developed for use with a centrifugal analyzer. The method is based on a modification of the uricase (urate:oxygen oxidoreductase, EC 1.7.3.3)/catalase (hydrogen peroxide:hydrogen peroxide oxidoreductase EC 1.11.1.6)/aldehyde dehydrogenase (aldehyde:NAD(P)+ oxidoreductase, EC 1.2.1.5)-coupled analytical scheme reported by Haeckel [Z. Klin. Chem. Klin. Biochem. 14, 101 (1976)]. Sensitivity and precision of the method are excellent, and results compare well with those obtained by the Kageyama procedure [Clin. Chim. Acta 31, 421 (1971)].

Aldehyde Oxidoreductases↗
PubMed1977

Progress and future of centrifugal analysers.

Applications of centrifugal analysers to the field of clinical chemistry have been reviewed. Specific areas covered include recent developments in clinical enzymology with emphasis on aspartate aminotransferase and alkaline phosphatase. Also included are newer methods for uric acid, bilirubins and applications of enzyme linked immunoassays and immunochemical nephelometric techniques. Studies are described of the optimization of the BCG dye-binding procedure for serum albumin using an early absorbance reading.

Alkaline Phosphatase↗
PubMed1977

Use of gel filtration to examine the distribution of calcium among serum proteins.

Gel filtration of serum by use of dextran bisacrylamide beads ("Sephacryl S-200," fractionation range: 5000-250 000 daltons), separates the serum proteins into three distinct peaks. We used an eluent containing (per liter) 140 mmol of sodium, 1.10 mmol of calcium, 0.50 mmol of magnesium, and 10 mmol of 2-([2-hydroxy-1, 1-bis(hydroxymethyl)ethyl]amino)ethanesulfonate buffer (pH 7.43 at 37 degrees C) to provide the physiological conditions necessary to maintain the equilibrium of bound calcium in serum. We examined the calcium binding by each of the three protein groups. Calculating the calcium bound per gram of protein in each peak, we found that proteins in the first peak (alpha2-macroglobulin, IgM, haptoglobins) bind about the same amount of calcium per gram as does albumin. The proteins of the second peak (largely IgG and IgA) bind less calcium than does albumin, which is the protein accounting for 90% or more of the third peak. We also were able to calculate intrinsic association constants for calcium/albumin under physiological conditions.

Blood Proteins↗
PubMed1976

The effect of a short burst of exercise on activity values of enzymes in sera of healthy young men.

We report the effect of exercise on the activity values of five enzymes in sera as studied in four healthy male volunteers. The underlying purpose of this present study was to produce an increase in the activity values in the sera of selected enzymes found in muscle. Then by observing the decay rate of these enzymes, we computed the inter-individual differences in clearance rates serum half-life) of these enzymes. Blood specimens were collected just prior to exercise, 1 h after excerise, and on eight additional times up to 93 h after exercise. All specimens were assayed on one occasion for activity values of creatine kinase, asparate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase. We found increases in the three muscle enzymes with average increases being: creatine kinase, +116%; asparate aminotransferase, +41%; and lactate dehydrogenase, +32%; all of which remained above baseline values for 53 h or longer. In the case of creatine kinase, a monoexponential decay curve depicted the data (from the 19-h specimen to the 67-h specimen). The calculated "apparent serum half-life" for creatine kinase varied from 38 h to 118 h in the subjects tested.

Adult↗
PubMed1976

Separation and quantitation of serum constituents associated with calcium by gel filtration.

Gel filtration of serum by use of polyacrylamide beads (Biogel P-2) separates total colcium into four distinct peaks: an initial peak, corresponding to protein-bound calcium; a second peak containing the calcium complexes of citrate, phosphate, lactate, and sulfate; a third peak containing calcium bicarbonate; and a fourth peak or trough corresponding to the serum ionic calcium. An eluent containing (per liter) 140 mmol of sodium, 1.1o mmol of calcium, 0.50 mmol of magnesium, and 10 mmol of 2-([tris(hydroxymethyl)methyl]amino)ethanesulfonic acid(pH 7.40 at 37 degrees C) provides physiological conditions that determine the equilibria between these calcium components. Association constants determined under these conditions permit calculation of the expected concentration of the calcium complexes in each tube of eluent, and these concentrations closely correspond to the amount of bound calcium measured experimentally. The mean distribution of calcium in healthy individuals, as determined by this method, is (per liter): calcium protein, 1.00 mmol; calcium complexes, 0.31 mmol; and ionic calcium, 1.07 mmol.

Bicarbonates↗
PubMed1976

An integrated approach to lipid profiling: enzymatic determination of cholesterol and triglycerides with a centrifugal analyzer.

We describe enzymatic methods for determination of cholesterol and triglycerides (triacylglycerols), adapted for use with a centrifugal analyzer. Triglycerides are determined by a two-point kinetic method, which utilizes a single glycerol standard for calibration and provides for a within-run reagent blank correction. The endpoint determination of cholesterol combines the unique blanking capabilities of the centrifugal analyzer to correct for sample and reagent blank interferences. Results correlate well with those obtained by procedures standardized by the Lipid Research Clinics Program for use with a continuous-flow system.

Autoanalysis↗
PubMed1976

Improved method for measurement of inorganic phosphate in serum with a centrifugal analyzer.

A direct mehtod [Clin. Chim. Acta 46, 113 (1973)] for determination of inorganic phosphate in serum was adapted for use with a centrifugal analyzer. Contamination is minimized and analysis rate maximized by doing the reaction in the reagent wells of the transfer disc and by utilizing the high-speed spectrophotometric and data-reduction capabilities of the centrifugal analyzer. Hemolysis, icterus, and moderate lipemia cause no interference. Grossly lipemic sera and sera from patients with plasma cell dyscrasias can be analyzed by incorporating appropriate blanking and dilution techniques. The method exhibits excellent sensitivity and precision and results correlate well with those from a continuous-flow procedure.

Autoanalysis↗
PubMed1976

Adaptation of blank-corrected methods for measurement of total and conjugated bilirubin and uric acid to the centrifugal analyzer.

The blank-corrected determination in serum of total and conjugated bilirubin and of uric acid has been adapted to the centrifugal analyzer. Bilirubin is measured by a modified Jendrassik and Grof procedure; uric acid is determined kinetically by using a reaction based on reduction of ferric ion, including a uricase-treated blank. Sensitivity and precision of both methods are excellent, and results compare well with those obtained by commonly used procedures.

Autoanalysis↗
PubMed1975

Evaluation of kinetic light scattering as an approach to the measurement of specific proteins with the centrifugal analyzer. I. Methodology.

A laser-modified centrifugal analyzer was used to develop kinetic light scattering methods for the measurement of human immunoglobulins IgG, IgA, and IgM. Comparison of equilibrium light scattering methods with kinetic procedures for IgG and IgA demonstrate equivalent precision and relative accuracy. However, quantitative results obtained by equilibrium and kinetics methods for IgM were found to differ significantly. Recovery studies performed with purified IgM have shown that both methods can yield quantitative results in the normal range. Our observations demonstrate that the technique offers a viable and in some respects a superior alternative to other methods currently used in the clinical laboratory.

Autoanalysis↗
PubMed1975

Evaluation of kinetic light scattering as an approach to the measurement of specific proteins with the centrifugal analyzer. II. Theoretical considerations.

Development of centrifugal analyzers capable of making light-scattering measurements has prompted the investigation of the application of this type of instrumentation to the measurement of specific proteins. Investigation of antigen/antibody complex dimension and the kinetics of the IgG/anti-IgG reaction as followed by light scattering are examined in relation to improved analytical methodology. The effect of nonspecific protein on the reaction rate has been investigated for IgM, and data are presented that provide insight into the mechanism of the effect of periodic mixing.

Antigen-Antibody Reactions↗