bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma Cortisol Determination: Radioimmunoassay and Competitive Protein Binding Compared
Authors: Farmer Robert W , Pierce Charles E 
Published: January 2020

Abstract
A simple radioligand assay has been developed for measuring cortisol in plasma and urine. The antiserum was produced in rabbits by using cortisol-21-hemisuccinyl-bovine serum albumin as the antigen. The standard curve was linear from 0-1000 pg. A small aliquot of ethanol-precipitated plasma or urine is directly assayed. Interassay variability of 56 separate assays of a normal plasma pool during six months was: mean, 224 µg/liter; range, 210-238 µg/liter; CV, 3.2%. In assay of multiple samples obtained between 0800 and 1800 hours from normal young men, radioimmunoassay (RlA) gave consistently lower values than did competitive protein binding (CPB). The relationship, as calculated from results for 41 single samples, is expressed by the equation RIA = 0.713 CPB + 0.59, suggesting that the normal range for RIA should be 35-180 µg/liter rather than the 50-250 µg/liter usually cited. Although there is crossreactivity with 11-deoxycortisol, this assay is clearly superior to CPB: it is more specific, has a wider range (&lt;8-400 µg/liter), and requires less technician time.
Preparation and Evaluation of a Water-Soluble Cholesterol Standard
Authors: Klein Bernard , Kleinman Norman B , Foreman James A 
Published: January 2020

Abstract
We synthesized some inorganic and organic salts of cholesteryl hemisuccinate. Aqueous solutions of the morpholine salt, at concentrations equivalent to 400 mg of cholesterol per deciliter, have been evaluated as aqueous cholesterol standards and compared to alcoholic cholesterol solutions in analyses for cholesterol in serum, as performed by two analytical reference procedures. No significant differences were found. The usefulness of solutions of this salt as additives for serum controls or recovery studies has been also demonstrated.
Specific Automated Method for Measurement of Urinary Hydroxyproline
Authors: Seymour G C , Jackson M J 
Published: January 2020

Abstract
An automated continuous-flow method is described for estimating total hydroxyproline in urine. The method utilizes column chromatography on sulfonated polystyrene resin, the eluate being reacted with chloramine-T and p-dimethylaminobenzaldehyde to produce a colored complex that is measured at 560 nm. The method is sensitive and specific, and requires 50 min per analysis.
Evaluation of the Adaptation of the Glucose Oxidase/Peroxidase-3-Methyl-2-benzothiazolinone hydrazone-N, N-Dimethylaniline Procedure to the Technicon "SMA 12/60," and Comparison with Other Automated Methods for Glucose
Authors: Carey R Neill , Feldbruegge Donald , Westgard James O 
Published: January 2020

Abstract
We have evaluated the Technicon SMA 12/60 modification of a glucose oxidase/peroxidase-3-methyl-2-benzothiazolinone hydrazone-N, N-dimethylaniline method, and find it acceptable. Added bilirubin, creatinine, dextrans, and uric acid did not interfere. We compared values for patients’ sera by this method to those by the glucose oxidase/peroxidase-2,2'-azinodiethylbenzothiazoline-6-sulfonic acid, neocuproine, o-toluidine, ferricyanide, and hexokinase methods. For comparisons to the hexokinase method (which we used as a reference method), n = 371, slope = 1.00, y-intercept = 1.57 mg/dl, and bias = 2.05 mg/dl. For the method being evaluated, the run-to-run average monthly standard deviation was 2.9 mg/dl for a control product for which the mean was 85 mg of glucose per deciliter, and 4.3 mg/dl for a product for which the mean was 240 mg/dl. All six methods were compared for effects of uremic sera, icteric sera, and sera from patients receiving ascorbic acid therapy or hypoglycemic drugs.
Enzymatic Blood Glucose Determination by Colorimetry of N,N-Diethylaniline-4-Aminoantipyrine
Authors: Kabasakalian Peter , Kalliney Sami , Westcott Anita 
Published: January 2020

Abstract
The hydrogen peroxide produced from glucose by glucose oxidase action at pH 7 is determined by the peroxidase oxidative coupling of N,N-diethylaniline with 4-amino-antipyrine. A 20-µl sample of plasma or serum is reacted at room temperature for 10 min. The sensitivity of the method is such that 60 µg of glucose (300 mg/dl) in a final volume of 5 ml gives an absorbance of 0.8 at 553 nm with a 1-cm cell. Absorbances are linearly related to glucose concentrations as high as 10.00 g/liter.
Design of a Portable Solid-State Hemoglobinometer
Authors: Rose Angela W , Steadman John W 
Published: January 2020

Abstract
The most widely used and accepted method for hemoglobin determination is the cyanmethemoglobin method. However, laboratory spectrophotometers used with this procedure are not amenable to field use. We describe the design of a portable hemoglobinometer for use with the cyanmethemoglobin method. Solid-state light sources and detectors are used, and a simple meter readout of hemoglobin is produced. Results obtained with the portable hemoglobinometer are presented and compared with assays of the same blood by the usual methods.
Improved Automated Method for Determining Serum Albumin with Bromcresol Green
Authors: Lolekha Porntip H , Charoenpol Wasana 
Published: January 2020

Abstract
An automated method for determining serum albumin with bromcresol green according to Doumas et al. [Clin. Chim. Acta 31, 87 (1971)] was simplified and improved for use in routine analysis. The manifold is simpler, there is better sample separation and less sample interaction, both within-run and day-to-day run precision are excellent, and results agree well with those obtained by electrophoresis on cellulose acetate.
Interlaboratory Evaluation of Proficiency Testing in Urinary δ-Aminolevulinic Acid Analyses
Authors: Berlin Alexander , del Castilho Pierre , Smeets Jan 
Published: January 2020

Abstract
Twenty-six European laboratories have participated in a study of various methods used for determination of δ-aminolevulinic acid in urine, to determine to what extent they give comparable results when performed by different laboratories. None of the methods as used in the program appeared to be precise and accurate enough to allow each of several laboratories to detect the small differences in urinary δ-aminolevulinic acid that would result from differences in exposure to environmental lead. Variation among results obtained by different laboratories using the same technique probably reflects differences in the practical experience each laboratory had with the various techniques, rather than intrinsic problems with the methods themselves.
New Assay for Tryptophan and Its 5-Hydroxyindole Metabolites in Blood
Authors: Guilbault George G , Froehlich Peter M 
Published: January 2020

Abstract
We describe a new cation-exchange fluorometry procedure for separation and measurement of three 5-hydroxyindole metabolites of tryptophan in blood. The metabolites are detected and measured via the fluorescence emitted in the visible region when the separated metabolite is added to a hydrochloric acid-ascorbic acid mixture. The assay requires only 30 min and is both selective and sensitive. The normal concentration of 5-hydroxytryptamine (serotonin) in serum is 98 µg/liter; 5-hydroxyindole acetic acid and 5-hydroxytryptophan are normally present in concentrations of less than 20 µg/liter.
A Centrifugal Analyzer with a New All-Digital Measurement System
Authors: Avery J , Gregory R P , Renoe B W , Woodruff T , Malmstadt H V 
Published: January 2020

Abstract
An accurate, all-digital measurement system has been developed for use in a centrifugal analyzer system. The output of the radiation detector is converted directly to a digital count by a new type of charge-to-count converter. The converter is characterized by exceptional linearity and stability, and has a wide dynamic range. A gating and counting unit integrates the output of the charge-to-count converter and simultaneously measures the period of integration. The integration effectively discriminates against noise and allows an optimum amount of information to be extracted from the signal during the measurement period. Measurement of the integration period reduces requirements for synchronization and control devices, thus simplifying overall analyzer design. Control and data manipulation functions are performed by a minicomputer. The programs were written in OS/8 FORTRAN. The basic measurement principles of the new system and test results are described.
High-Resolution Gas-Chromatographic Analysis of the Volatile Constituents of Body Fluids, with Use of Glass Capillary Columns
Authors: Novotny Milos , McConnell Michael L , Lee Milton L , Farlow Raleigh 
Published: January 2020

Abstract
Trace volatile constituents of human urine, serum, and cerebrospinal fluid were concentrated on a porous polymer precolumn, and resolved with high-efficiency glass capillary columns. Thin-film glass columns facilitate effective resolution of underivatized compounds within the volatility range up to docosane in relatively short analysis times. Glass capillary columns coated with stationary phases of different polarity were used. Recorded volatile metabolic profiles of human urine are altered after the sample is treated with β-glucuronidase and sulphatase.
Evaluation of a Solubility Test Kit and an Automated Machine for Detecting Hemoglobin S
Authors: Wilson Sylvia M , Schmidt Robert M 
Published: January 2020

Abstract
A solubility test kit (Sicklequik) and an instrument (SCAT Screener) designed to semiautomate the reading of the solubility test for the detection of hemoglobin S were evaluated for accuracy, precision, and specificity. Two hundred blood samples from persons with normal and variant hemoglobins were tested. Results were satisfactory for the test kit. However, the instrument gave incorrect results for 7% of the samples tested for hemoglobin S.
Evaluation of an Automated Selective-Ion Electrolyte Analyzer for Measuring Na+, K+, and Cl- in Serum
Authors: Lustgarten Jack A , Wenk Robert E , Byrd Charles , Hall Barbara 
Published: January 2020

Abstract
An automated analyzer, in which ion-selective electrodes are used to measure sodium, potassium, and chloride in serum, was assessed in a clinical setting. Day-to-day precision, evaluated by replicate analysis of serum pools, yielded the following coefficients of variation for sodium, potassium, and chloride, respectively: 0.99%, 1.39%, and 0.67%. Values for chloride in both commercial control sera and aqueous standards were linearly related to concentration over a range of at least 10-220 mmol/liter; however, results with the potassium and sodium electrodes showed slight curvilinearity over the range 0-24 and 10-220 mmol/liter, respectively. Mean recoveries for sodium, potassium, and chloride for concentrations covering the clinically important ranges were 98.3-102.3%, 95.9-100.0%, and 97.8-102.0%. The only important differences between experimental and comparison methods in sera were falsely high values obtained with the ion-selective electrode for K+ (caused by supranormal ammonia concentrations) and for Cl- (caused by administered bromide). Mean sodium and chloride values obtained with the electrode did not differ significantly from values obtained by flame-emission photometry or coulometry for duplicate patients’ specimens, but potassium values did differ slightly (P = .05).
Total Neutral 17-Ketosteroids
Authors: Kafka Marian S , Bondy Philip K 
Published: January 2020

Abstract
The Masuda and Thuline method for measuring urinary neutral 17-ketosteroids has been modified by substituting polyethylene bottles and a mechanical shaker for separatory funnels and manual shaking, and by developing the color and reading it in the same test tube. Combining Zimmermann reagents before addition eliminates the necessity for frequently pipeting small volumes. The new method permits the analysis of 10 to 15 urines in a single operation without sacrificing accuracy or specificity.
Determination of Sulfobromophthalein in Serum
Authors: Seligson David , Marino Jean , Dodson Elizabeth 
Published: January 2020

Abstract
A method for the determination of BSP is presented which eliminates errors due to protein-binding with albumin and artifacts due to bilirubin, hemoglobin, and turbidity. Measurements at two or three wavelengths are thereby reduced to measurement at one wavelength. The method while simplified appears to be accurate, particularly in the low ranges.
Influence of Variations in Body-Fluid Volumes on Sodium Metabolism in Man
Authors: Josephson Berth 
Published: January 2020

Abstract
A review has been given of recent papers on the influence of acute changes in extracellular, extravascular fluid volume and in plasma volume on the salt metabolism. The influence of intravascular pressure, pitressin, adrenal steroids, etc., has been mentioned. Some work from the author's laboratory has been reported. It was found in this laboratory that a large intravenous infusion-25 ml./min. during 1-2 hours-of iso-oncotic glucose has no influence on sodium excretion in normal man, but that it gives rise to a very high increase of the sodium output in cases of arterial hypertension. Later on it was found that patients with cardiac failure behave as the hypertensive do in this respect. On the other hand, an intravenous infusion of a corresponding amount of iso-oncotic dextran solution gives a considerable decrease of sodium excretion in healthy subjects as well as in patients with the above-mentioned diseases. The correlation between these results and the changes of the kidney function and the renal hemodynamic have been discussed.
A Toxicologic Service in a General Hospital
Authors: Nobel Sidney 
Published: January 2020

Abstract
Information and suggestions found of value in a general hospital in dealing with toxicologic problems are presented. Relevant problems such as good liaison between the emergency room and the laboratory, sources of information on product composition, the preparation of an odor reference shelf, and selection of methods to help meet the majority of situations encountered have been discussed. The importance of participation in public-health education programs has also been indicated.
Chronic Alkalosis with Damage to the Central Nervous System
Authors: Natelson Samuel 
Published: January 2020

Abstract
A condition of chronic alkalosis has been described with central nervous system damage. This syndrome is characterized by alkaline blood pH, and elevated total CO2 levels, associated with central nervous system damage. It is apparently caused by sodium retention as indicated from the sodium to chloride ratios in the urine excreted by these patients. In alkalosis, the output of fluid is often greater than the input. Sodium chloride solutions intravenously tend to aggravate the alkalosis. Potassium chloride or ammonium chloride will relieve the alkalosis only temporarily. Pitressin will not correct the abnormal sodium to chloride ratios in the urine. A carbonic anhydrase inhibitor (Diamox) will lower the CO2 levels, and correct the blood pH. Its action seems to be due to its ability to correct the sodium to chloride ratios in the urine excreted. The effect of Diamox will persist for several days after its administration.
Rapid System of Microchemical Analysis for the Clinical Laboratory
Authors: Saifer Abraham , Gerstenfeld Shirley , Zymaris Michael C 
Published: January 2020

Abstract
A rapid, semiautomatic system of microchemical analysis for the clinical chemistry laboratory has been proposed. Five basic elements of this system are: (1) The use of siliconated-heparinized plasma. (2) The use of the calibrated-pipet-tip buret technic for measuring small (0.10-ml.) samples. (3) The use of the decantation principle as a precision step in making quantitative transfers. (4) The use of automatic syringe pipets for adding constant volumes of reagents, (5) The use of specific enzymatic methods, whenever these are applicable, for the determination of biologic constituents.
The analytic system has already been applied to the determination of such important biologic constituents as glucose, urea nitrogen, phosphorus, acid and alkaline phosphatases, sodium and potassium, calcium, and total protein.
The semiautomatic system permits the use of microprocedures in a clinical chemistry laboratory by persons of limited technical skill.
The Microbiologic Assay of Vitamins in Clinical Chemistry
Authors: Sobotka Harry 
Published: January 2020

Abstract
The examples which have been given above in the cyanocobalamin and folic acid field illustrate the usefulness of the microbiologic assay of vitamins in investigate work. The application of these methods to routine determinations will follow, once the indications for their usefulness are established. Table 7 summarizes the vitamins for which we have developed assay methods, the microorganisms used, and their sensitivity.
The methods described are much simpler than they may appear to be at first sight, and they require no expensive or special equipment. They can become in due course routine procedures and will contribute to one of the lesser known chapters of clinical chemistry.
Determination of Serum Lipoproteins by Paper Electrophoresis after Preliminary Staining with Sudan Black-B
Authors: Kanabrocki Eugene L , Kaplan Ervin , Kinnory David S , Imperato Alfred A , Berry John E , Baker Lyle A 
Published: January 2020

Abstract
A modification of McDonald's method for the determination of serum lipoproteins is described in which serum is prestained with Sudan Black B dye before paper electrophoretic separation.
Normal values were determined in 24 adults. Average value for α lipoproteins was 39.2 per cent and for β lipoproteins 60.8 per cent. In 31 patients with proved coronary artery disease, 22.7 per cent α lipoprotein and 77.3 per cent β lipoprotein were found. These results are in general agreement with those of other investigators using different methods.
Biological Role of Magnesium
Authors: Pleshchitser A La 
Published: January 2020

Abstract
Fersman (1934) commented on the relatively unimportant role of magnesium in biochemical processes. The comparatively limited radius of its ions, the stability and relative insolubility of its compounds prevent its taking an active part in the reactions of living matter. On the other hand, we have the statement of Vernadskii that in the plankton film of the ocean, in the ordinary accumulations and more massive growths, the amount of magnesium-containing chlorophyll must reach the order of 10-4 per cent by weight, if not higher, so that a small quantity of magnesium, entering into the composition of the chlorophyll-complex of the plankton, ultimately regulates the main part of the oxygenating function of living matter, the creation of free atmospheric oxygen. The material summarized by us likewise affords evidence of the importance of the role of magnesium in biological processes.
All this, however, does not justify sharp differentiation between the biological role of magnesium and its role in biochemical processes. In all probability these processes are conditional to each other, although they are not identical processes.
It is important to note the established and incontestable role of magnesium in many enzymatic processes in both the plant and animal kingdoms.
The antagonistic action between magnesium and calcium, resulting from artificial changes in the ratios of these elements in soil, plants, and animals, can hardly occur under natural conditions, and, conversely, it must be assumed that a labile equilibrium between these elements is always maintained.
The depressing action of magnesium ions on the central nervous system acquires considerable biological significance, since this permits the assumption that these ions in the animal organism may facilitate inhibitory processes in the nerve cell and insure the normal course of catabolic and anabolic processes.
The narcotic and cholinolytic effects of magnesium constitute the basis for the wide therapeutic use of magnesium salts in medical practice.
Pitfalls in measuring plasma cholesterol in the Smith–Lemli–Opitz syndrome
Authors: Jira Petr E , de Jong Jan G N , Janssen-Zijlstra Fokje S M , Wendel Udo , Wevers Ron A 
Published: January 2020

AbstractCorrect quantitative results for plasma cholesterol, 7-dehydrocholesterol (7-DHC), and 8-dehydrocholesterol (8-DHC) are invaluable for making the correct diagnosis in patients with the Smith–Lemli–Opitz syndrome (SLO) and for biochemical monitoring of these patients during therapy. The enzymatic method for cholesterol measurement based on cholesterol oxidase gives falsely high values for plasma cholesterol in samples from patients with SLO. Both 7-DHC and 8-DHC contribute substantially to the test result, given that they are accepted substrates of cholesterol oxidase. All cholesterol methods making use of this enzyme are expected to give unreliable results with plasma samples from SLO patients. Cholesterol values found with these methods may be low-normal in individual cases with SLO. Therefore, other techniques for measuring cholesterol, 7-DHC, and 8-DHC, e.g., gas chromatography, should be used for diagnosing these patients and for follow-up during therapy. However, a normal value for plasma cholesterol, as obtained by gas chromatography, does not exclude SLO. The diagnosis should always be confirmed or excluded by testing for the presence of high concentrations of 7-DHC and 8-DHC in plasma. We found that one patient with a severe form of the disease had a plasma cholesterol concentration of 20 μmol/L—to our knowledge, the lowest value ever recorded in a human being.
Measurement of lactate in cerebrospinal fluid in investigation of inherited metabolic disease
Authors: Hutchesson Andrew , Preece Mary Anne , Gray George , Green Anne 
Published: January 2020

AbstractMeasurement of lactate concentrations in cerebrospinal fluid (CSF) has been suggested as part of the investigation of inborn errors of the electron transport chain, but little information exists regarding the reference range in children or the relationship between CSF and plasma concentrations. In 39 children without bacterial meningitis, diabetes, or recent seizures, we determined that the median (range) lactate concentrations in CSF and plasma collected concurrently were 1.4 (0.8–2.2) and 1.5 (0.6–2.3) mmol/L; the regression equation was CSF lactate = (0.38 ± 0.06) plasma lactate + 0.83 (r2 = 0.14). In 8 of 11 (73%) children with electron transport chain defects, CSF lactate was ≥3.0 mmol/L; however, 2 of these 8 had a normal plasma lactate concentration. CSF lactate was also increased in 2 children with nonketotic hyperglycinemia. The finding that CSF lactate concentrations may be increased despite a normal plasma lactate value in children with electron transport chain defects is an important clue to the diagnosis of these disorders.