bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sodium Iodoacetate as an Antiglycolytic Agent in Blood Samples
Authors: Marbach Edward P , McLean Monty , Scharn Marilyn , Jones Tom 
Published: January 2020

Abstract
We evaluated the effect of sodium iodoacetate on glycolysis in a series of randomly selected blood samples from patients. Glucose values for serum and for serum with added sodium fluoride (2.5 g/liter) or sodium iodoacetate (2 g and 0.5 g/liter) were compared at room temperature. Respective declines in glucose values averaged 170, 40, 30, and 30 mg/liter after 24 h. Iodoacetate-preserved (0.5 g/liter) samples showed no visible hemolysis. Results of determinations of urea with urease and of other tests on SMA 12/60 (Technicon) panels were unaffected.
Abnormal Electrophoretic Mobility of a Creatine Kinase MM Isoenzyme
Authors: Velletri Kimberly , Griffiths William C , Diamond Israel 
Published: January 2020

Abstract
We describe the abnormal electrophoretic mobility of an MM isoenzyme of serum creatine kinase on cellulose acetate, a change evidently attributable to complexing of the enzyme with serum β-lipoprotein. This complex formation also may lead to difficulty in interpretation of creatine kinase isoenzyme separation by ion-exchange column chromatography.
Radioimmunoassay of Methaqualone and Its Monohydroxy Metabolites in Urine
Authors: Berman Ann R , McGrath James P , Permisohn Robert C , Cella James A 
Published: January 2020

Abstract
A commercial radioimmunoassay kit was evaluated for efficacy in detecting methaqualone or its metabolites in urine of persons receiving this drug. The drug and its unconjugated 3'- and 4'-monohydroxy metabolites could be detected equally well. The unconjugated α-monohydroxy metabolite was about 80% as reactive and the unconjugated 6-monohydroxy metabolite reacted only very weakly. Quantitation of the conjugated metabolites was less sensitive than of unconjugated. Nineteen urine specimens which reacted positively to radioimmunoassay and which thin-layer chromatography had shown to contain methaqualone and its metabolites were also examined by gas-liquid chromatography. Those specimens that reacted strongly to radioimmunoassay contained high concentrations of the drug or its metabolites. In the specimens examined by gas-liquid chromatography, the apparent concentrations of the metabolites were generally higher than those of the drug itself. Methaqualone in combination with its unconjugated metabolites reacted additively with the radioimmunoassay, resembling the same concentration of parent drug alone. Detection limits were between 10-200 µg/liter.
Comparison of Commercial Kits for Radioimmunoassay: III. Radioassay of Serum Folate
Authors: Kubasik Norman P , Volosin Michael T , Sine Harrison E 
Published: January 2020

Abstract
We evaluated six commercial radioassay kits in which tritium or iodine tracers are used to measure serum folate. We assessed the adequacy of the literature supplied with the kits, within-run precision, reagent stability, analytical recovery of added pteroylglutamic acid and N-methyltetrahydrofolic acid, results of analysis of patients' samples, and minimum detection limits. There were serious discrepancies among manufacturers' kits in each of these respects. Such discrepancies could affect interpretation of results and of data on like samples derived from different laboratories that are using different kits. Laboratories are urged to assess carefully the materials and method supplied by a manufacturer before putting a kit to clinical use.
Determination of Serum Thyroxine after Dissociation from Thyroxine-Binding Globulin in Alkaline Solution and Adsorption on Dextran-Coated Charcoal
Authors: Wong William H 
Published: January 2020

Abstract
A competitive protein-binding procedure for determining serum thyroxine is described in which thyroxine is first dissociated from serum thyroxine-binding globulins in an alkaline solution. After binding equilibration, the unbound thyroxine is separated by dextran-coated charcoal. The procedure takes only 100 µl of serum, requires no evaporation, and is sensitive and reproducible. Results by this procedure correlate well with those for a generally accepted method.
Determination of Diphenylhydantoin in Human Serum by Spin Immunoassay
Authors: Montgomery Mark R , Holtzman Jordan L , Leute Richard K , Dewees John S , Bolz Gunner 
Published: January 2020

Abstract
A spin immunoassay for diphenylhydantoin is reported, which appears to give an accurate and precise estimate of serum diphenylhydantoin concentrations, as judged by the disappearance of [14C] diphenylhydantoin from the serum of a rabbIt. The assay also appears to be a reliable technique for routine diphenylhydantoin determinations, as judged from our experience with 28 patients. Serum diphenylhydantoin concentrations in the range of 1.0-50.0 mg/liter are easily determined on a 50-µl sample. Except for primidone, no significant cross reactivity was observed with eight drugs that are commonly used in conjunction with diphenylhydantoin therapy. This fast, simple, and precise method therefore appears to be readily applicable to routine determination of diphenylhydantoin.
Methodologic Differences in Values for M-Proteins in Serum, as Measured by Three Techniques
Authors: Daniels Jerry C , Vyvial Theona M , Levin William C , Ritzmann Stephan E 
Published: January 2020

Abstract
Accurate and reproducible measurement of M-proteins is essential for managing patients with monoclonal gammopathies, but serum protein electrophoresis, radial immunodiffusion, and electroimmunodiffusion yield comparatively divergent results. We have studied these differences and their causes. Sera from cases of IgG-monoclonal gammopathy, IgA-monoclonal gammopathy, and IgM-monoclonal gammopathy were assayed by each of the three techniques. Results indicated intermethod discrepancies as great as fivefold for all proteins studied. For IgG-monoclonal gammopathy, radial immunodiffusion values were uniformly higher; electroimmunodiffusion values were less consistently so. For IgA-monoclonal gammopathy, both radial immunodiffusion and electroimmunodiffusion gave lower results than did serum protein electrophoresis. For IgM-monoclonal gammopathy, results were variable, but values by radial immunodiffusion tended to be higher than, and electroimmunodiffusion comparable to, those for serum protein electrophoresis. The differences were not correlated with protein abundance, serum freshness, immunoglobulin class, light-chain type, ultracentrifugal characteristics, or electrophoretic mobility. Clearly, values for M-protein concentration depend on the techniques used to obtain them. We postulate that subclass differences may contribute to the diversity of radial immunodiffusion results, and that for electroimmunodiffusion the fixed electrophoretic mobility of M-proteins leads to unpredictable results. We conclude that serum protein electrophoresis is the best of the three assay techniques for M-proteins.
Lecithin—Sphingomyelin Ratio in Amniotic Fluid, as Assessed by a Modified Thin-Layer Chromatographic Method in Which a Commercial Pre-Coated Plate Is Used
Authors: Mallikarjuneswara Valyacheri R 
Published: January 2020

Abstract
Commercially available pre-coated thin-layer chromatographic plates consisting of silica gel supported on aluminum sheets were used to determine the lecithinsphingomyelin ratio in samples of amniotic fluid. These lipids were separated in a chloroform-methanol-water (65:25:4 by vol) solvent system (lecithin, RF = 0.33; sphingomyelin, RF = 0.25), and the spots were made visible in 5-15 min by heating to 180 °C after spraying with a solution of copper acetate (30 g/liter) in aqueous phosphoric acid (80 g/liter). The lipids were measured densitometrically after "peeling off" the adsorbent containing the spots by using a transparent cellulose ("Scotch brand") adhesive tape. Virtues of the original Gluck procedure are retained without need to heat the plates to 280 °C after spraying with corrosive aqueous sulfuric acid (698 g/liter) to make the lipids visible. Resuits for synthetic mixtures in concentrations within the physiological range and with a ratio of 0.5 to 3.0 showed an accuracy of 99% ± 7% (SD).
Some Nonparametric Statistical Tests for Quick Evaluation of Clinical Data
Authors: Gindler E Melvin 
Published: January 2020

Abstract
Some rapid statistical tests give (a) rapid answers on how well methods agree and control chart evaluation (sign and run tests) and (b) evaluation of distribution of test results (Tukey's quick test and run test). These tests mainly require counting of data and the use of the given nomograms. An unusual distribution of patient test values—that is, unusual when compared with the generally observed distribution of the data seen in a particular laboratory—may indicate laboratory error, alteration of specimens (as from poor collection and/or storage techniques, such as evaporation), or an unusual patient population.
Effect of Lactate Dehydrogenase Isoenzymes on the Coupled Enzymatic Assay for Alanine Aminotransferase Activity
Authors: Chang Michael M , Chung Tai Wha 
Published: January 2020

Abstract
We show an example of the importance of specifying the form of isoenzyme and source of indicator enzymes to be used in coupled enzymatic assays. When we compared H4 (pig heart) and M4 (rabbit muscle) isoenzymes of lactate dehydrogenase for their suitability as indicator enzymes in the assay for alanine aminotransferase activity, we found that about fourfold as much M4 as H4 was required in terms of lactate dehydrogenase activity to reflect accurately equivalent amounts of alanine aminotransferase activity. Moreover, the substrate specificities of the two isoenzymes differed quantitatively.
Examination of Some Factors Affecting Sensitivity and Reproducibility in Radioimmunoassay of Thyrotropin
Authors: Moser Russell J , Hollingsworth Dorothy R 
Published: January 2020

Abstract
Conditions for measuring human thyrotropin by radioimmunoassay have been investigated, to improve the sensitivity and reproducibility of the assay. The ChloramineT method of iodination was used, the reaction time being 20 s. Doubling the iodination reaction volume from 55 to 95 µl did not affect the immunoreactivity. Purification of labeled hormone by use of anion-exchange resin followed by silica (Quso G-32) instead of Sephadex gelfiltration or anion exchange alone yielded a product that was the least (&lt;4%) contaminated with Na125I. Human serum albumin (2.5 g/liter) in phosphate-buffered saline, instead of bovine serum, should be used as diluent for unknowns; within-assay variance was 3% for the former, 62% for the latter. The assay worked equally well for both pregnant and nonpregnant patients, with use of 50 to 100 µl of serum per determination. A five-week-old labeled hormone yielded higher values than did two-week-old material. Use of sequential saturation techniques (tracer added on day 3) resulted in a greater than 50% drop in B/B0 ratio in the standard curve between 0.39 and 50 microunits/ml. Somatotropin, choriomammotropin, and porcine insulin did not cross react in this system. Human follitropin and lutropin did cross react, and this cross reaction could not be prevented with as much as 40 international units of human choriogonadotropin per tube. With a total reaction volume of 0.4 ml before addition of second antibody, 0.2 ml of 10-fold diluted second antibody yielded a standard curve with lower nonspecific binding and higher maximum precipitation than one constructed by using only 20 µl of second antibody. In 29 euthyroid patients the mean thyrotropin value was 5.7 microunits/ml (range 2.8-11); nine hypothyroid patients had a mean of 112 microunits/ml (range 38-267); and 13 hyperthyroid subjects showed suppressed thyrotropin with a mean of 3.1 microunits/ ml (range 2.2-4.5). Following these suggestions, one can expect a more highly purified immunoreactive tracer and a more sensitive assay than is obtained with the procedure from the Pituitary Agency of the National Institutes of Health.
Use of Leuco-Dyes in the Quantitative Colorimetric Microdetermination of Hemoglobin and Other Heme Compounds
Authors: Ahlquist David Alan , Schwartz Samuel 
Published: January 2020

Abstract
Sensitivity, stability, and specificity of the color-producing reaction of hydrogen peroxide with benzidine, leucomalachite green, or o-dianisidine were tested in numerous systems containing hemoglobin and other hemoproteins. Use of urea or low temperature (to -12 °C), or both, was highly beneficial, especially with leuco-malachite green, for which the color reaction was stable, after about 15 min, for longer than 24 h, with a colorless blank. Absorbance was 0.3 at a final hemoglobin concentration of 0.27 mg/liter. Nonspecific color produced by substances such as FeCl3 and ascorbic acid was completely eliminated. Of the three leuco-dyes studied, only benzidine yielded a completely linear calibration curve, but its relative instability and reported carcinogenicity are serious disadvantages. No system tested eliminated completely the known inhibition by plasma of the peroxidase activity of these leuco dyes.
Manual Determination of Intra-Erythrocytic 2,3-Diphosphoglycerate in Whole Blood by Enzymatic Analysis, and Comparison with Ion-Exchange Chromatography
Authors: Detter James C , Gibson Donald F , MacMillan Stuart F , Oas Thomas H 
Published: January 2020

Abstract
A manual modification of an automated method [Atkinson, K. F., Clin. Chem. 18, 1001 (1972)] for enzymatic assay of 2,3-diphosphoglycerate is described, which is suitable for small laboratories. Samples are easily prepared for analysis, and preparations are stable for several months. Virtually all of the color generated in the colorimetric assay is produced by the diphosphoglycerate-catalyzed reaction. The coefficient of variation for multiple samples from a single subject was 2.4%. Delayed preparation of samples, particularly samples from some acidotic subjects, is shown to result in altered results. The enzyme method is compared with analysis by ion-exchange chromatography.
Free Amino Acids in Human Tonsillar Tissue
Authors: Doi Yasuyuki , Kataura Akikatsu 
Published: January 2020

Abstract
Free amino acids in the tonsils of 20 individuals were measured column chromatographically. Those always found in readily detectable amounts included O-phosphoserine, taurine, O-phosphoethanolamine, aspartic acid, hydroxyproline, threonine, serine, glutamic acid, proline, glycine, alanine, α-amino-n-butyric acid, valine, cystine, methionine, isoleucine, leucine, tyrosine, phenylalanine, ornithine, γ-amino-butyric acid, lysine, histidine, and arginine. Results were compared for three clinical pathological groups and for four age groups. Some abnormal values may result from the pathological conditions.
Simultaneous Determination of Serum Cholesterol and Triglycerides after Preliminary Column Chromatography
Authors: Moses Godfrey , Olivero Edwin , Draisey Thomas F 
Published: January 2020

Abstract
An isopropanolic extract of serum can be made suitable for the simultaneous estimation of cholesterol and triglycerides by passing it through a commercially-available chromatographic column containing activated metallic oxides in which alumina predominates. No centrifugation step nor phase separation is required. Use of the purified extract allows existing methods to be simplified and shortened without loss of reproducibility or stability. Results compare well with those obtained by traditional methods.
Technique for Determining Nickel in Blood by Flameless Atomic Absorption Spectrophotometry
Authors: Zachariasen Hans , Andersen Ivar , Kostol Carl , Barton Richard 
Published: January 2020

Abstract
We describe a technique for determining nickel in serum by flameless atomic absorption, with use of di methylglyoxime. The procedure permits a greater num ber of analyses per technician at a relatively low cost, yet provides acceptable accuracy and reliability. After the sample is evaporated and dry ashed in a muffle fur nace at 560 #{ 176} C for 5 h, the residual salts are dissolved in hydrochloric acid (1 mol/liter). Sodium citrate and di methylglyoxlme are then added for complexation of iron and nickel, respectively. The pH is adjusted to 9 with ammonia and the nickel dimethylglyoxime is extracted with methyl isobutyl ketone. The determination is carried out by injecting 50 µl of the organic phase into the graphite furnace, where the sample is dried at 120 °C and ashed at 1200 °C, respectively.
Influence of Myocardial Infarction on Serum Manganese, Copper, and Zinc Concentrations
Authors: Versieck Jacques , Barbler Fabrice , Speecke Albert , Hoste Julien 
Published: January 2020

Abstract
Reportedly, serum manganese concentrations increase after myocardial infarction, closely correlated with increased serum aspartate aminotransferase activity. However, these conclusions are apparently based on analyses of contaminated samples. Serum manganese concentrations after myocardial infarction have been re-investigated by neutron activation analysis, and no significant increase could be demonstrated. Because serum copper and zinc could be determined simultaneously, analyses for these trace elements are also reported, which confirm the findings of others. After myocardial Infarction a statistically significant (0.02 &lt; P &lt; 0.05) increase in serum copper and a statistically significant (0.001 &lt; P &lt; 0.01) decrease in serum zinc were observed.
Determination of Cadmium in Blood and Urine by Graphite Furnace Atomic Absorption Spectrophotometry
Authors: Perry Elizabeth F , Koirtyohann S Roy , Perry H Mitchell 
Published: January 2020

Abstract
We describe a method for measuring quantities of cadmium in blood, plasma, and urine by using graphite furnace atomic absorption preceded by wet ashing. The method appears to be extremely accurate and reproducible (coefficient of variation is 7% for 2.8 µg/liter concentration), with a detection limit of 2 pg.
Serum Immunoglobulins after Surgical Operation
Authors: Fuller Janet M , Keyser J W 
Published: January 2020

Abstract
We measured immunoglobulins in the sera of 33 patients on days 1, 3, 6, 10, and 17 and three to four weeks after surgical operations (mostly hysterectomy or appendectomy) or (six patients) after spinal injury. In the absence of infection or blood transfusion, IgG usually decreased slightly and transiently after hysterectomy or appendectomy, as did IgA or IgM after hysterectomy. IgD concentrations showed no consistent changes, but in one patient after hysterectomy and with minimal infection IgD concentration decreased sharply, which contrasted with significant and early increases in IgG, IgA, and IgM. IgD concentration was not correlated with type of operation, presence of infection, or changes in the other immunoglobulins. IgE concentrations either did not change or, in some patients, increased or decreased initially, after operation. We conclude that immunoglobulin concentrations in serum are subject to multiple, unpredictable influences after trauma.
Evaluation of the New "System Olli 3000"Kinetic Ultraviolet Analyzer for Measuring Aspartate and Alanine Aminotransferase and Lactate Dehydrogenase Activities in Serum
Authors: Adlercreutz Herman , Peltonen Veikko , Voipio Tauno 
Published: January 2020

Abstract
A new fast kinetic analyzer, System Olli 3000, is evaluated as an instrument for the routine clinical laboratory measurement of the activities of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in serum. The System Olli 3000 consists of dispensers for simultaneous multiple dispensing of sample and reagents, incubators, vortex-type shakers, and a photometer with quartz fibre optics connected to a computer, allowing cycling measurements of 24 cuvets 24 times in 2 min. An unique slope search algorithm is described. The system shows a high degree of precision and a wide linearity range; activities of at least 10-fold the normal upper limit for all three of these enzymes can be measured without diluting the serum sample. As many as 380 analyses per hour (including calibration and blanks) can be carried out by one technician. For comparison, enzyme measurements were also made with an LKB 8600 Reaction Rate Analyzer and a Pye Unicam SP 8005 spectrophotometer coupled on-line to an IBM 1800 computer. Results obtained with the different instruments correlated well, especially in the region of main interest, i.e., above the normal upper limit. We conclude that the new instrument has many potentialities in kinetic analyses of nonenzymatic constituents in biological fluids.
Radioimmunoassay of Plasma Testosterone, with Use of Polyethylene Glycol to Separate Antibody-Bound and Free Hormone
Authors: Anderson Peter H , Fukushima Kimiko , Schiller Harvey S 
Published: January 2020

Abstract
We have developed a reliable radioimmunoassay for testosterone in plasma, polyethylene glycol ("Carbowax 6000") being used to separate antibody-bound and free hormone. Testosterone is separated from interfering steroids, notably dihydrotestosterone, by liquid—liquid partition chromatography on infusorial earth (Celite). The assay is sensitive (9 pg for standards), precise, and accurate. The lowest measurable concentration of testosterone is 350 ng/liter for plasma from men and 70 ng/liter for plasma from women. Intraand inter-assay coefficients of variation were 6.9% and 9.7%, respectively, for plasma from men, and 9.6% and 11.8%, respectively, for plasma from women. Our method for separating antibody-bound and free hormone is practical and convenient and may be generally applicable to all radioimmunoassays of steroid hormones in plasma.
Gas—Liquid Chromatography of Phenylalanine and Its Metabolites in Serum and Urine of Various Hyperphenylalaninemic Subjects, Their Relatives, and Controls
Authors: Kitagawa Teruo , Smith Barbara A , Brown Eleanor S 
Published: January 2020

Abstract
Phenylalanine and its metabolites were determined in serum and urine of phenylketonuric subjects and in subjects with milder hyperphenylalaninemia in whom blood phenylalanine concentrations were usually &lt;200 mg/liter. Metabolite concentrations were related to serum phenylalanine, and in hyperphenylalaninemic subjects were between those for treated and untreated phenylketonuric subjects. Phenyllactic and phenylpyruvic acids were excreted by all of the mild hyperphenylalaninemic subjects except for the youngest (one-year-old twins) and the only subject with a serum phenylalanine of &lt;100 mg/liter. Serum and urinary metabolites of heterozygotes of both conditions were similar before and after a phenylalanine load. The similar pattern of metabolites in phenylketonuric and mild hyperphenylalaninemic subjects reinforces the belief that the latter have some phenylalanine hydroxylase activity, and that this is the essential difference between the two groups.
Thermochemical Determination of Glucose in Serum, Plasma, and Whole Blood without Prior Deproteinization
Authors: McGlothlin C David , Jordan Joseph 
Published: January 2020

Abstract
Glucose can be determined by phosphorylatlon in the presence of hexokinase (EC 2.7.1.1) by using Mg2+/ (ATP)2- as the phosphorylating agent. A novel instrumental quantitation method is described, direct injection enthalpimetry, whereby the heat of the enzymatically catalyzed reaction was measured. The reaction was allowed to proceed to virtual completion (99.5+%) in an adiabatic Dewar vessel at 25.00 ± 0.01 °C (range). Samples were sequentially injected into a reaction mixture consisting of hexokinase, ATP, Mg2+, and a tris(hydroxymethyl)aminomethane buffer (pH 8). Single analyses required &lt;2 min for 0-3 g/liter samples. The linear dynamic range was 0.3-10 g/liter, with zero intercept and a precision and accuracy of 2%. Electrical calibration in situ obviated the need for chemical standards, and because protein and color do not interfere, no sample pretreatment was necessary before analysis.