bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Rapid Enzymatic Method for Estimating Ethanol in Body Fluids
Authors: Jones Donald , Gerber Louis P , Drell William 
Published: January 2020

Abstract
Alcohol dehydrogenase is a sensitive and selective reagent for the rapid, simple estimation of ethanol in body fluids. Serum need not be first deproteinized, and losses encountered in distillation procedures are precluded. The difference between the absorbance (at 340 nm) of sample and reagent blank gives the ethanol content of the specimen directly after a 5 to 10 min reaction. The standard deviation of the method is 3.6 µg/100 ml and the coefficient of variation is 1.8%. Recovery of ethanol is best by the present method, as compared with gas chromatography or distillation-dichromate oxidation, for alcohol concentrations of less than 0.1 g/100 ml
Rapid Glucose Oxidase-Peroxidase Ultramicro Method for Determination of Blood Glucose
Authors: Lenz Paul H , Passannante Anthony J 
Published: January 2020

Abstract
A rapid, convenient, and easy ultramicro modification of the glucose oxi-dase-peroxidase method for determining blood glucose is described. The reagent mixture is prepared by mixing phosphate buffer (pH 5.0) with lyophilized enzyme-chromogen (o-dianisidine). To this is added 20 µl of plasma or serum. After 15 min at room temperature the reaction is stopped, and the reaction mixture cleared, by adding 4M HCI. Absorbance is read at 400 nm vs. a reagent blank or, preferably, against a reagent blank containing serum or plasma. The individual (prepackaged) reagents are stable for at least 10 months; the reagent mixture and the color of the acidified reaction product are stable for more than 5 h. Protein precipitation, apparently un-necessary, has been eliminated. Absorbancies obtained by this method are linear for glucose concentrations as great as 300 mg/100 ml. Heparin, Parasepts, and benzoic acid do not inhibit the reaction.
Correlation of Laboratory Tests and Clinical Evaluation in Phenotyping of Lipoproteinemias
Authors: Winkelman James , Wybenga Donald R , Ibbott Frank A 
Published: January 2020

Abstract
Accuracy of phenotyping of lipoproteinemias by electrophoresis was assessed by comparing the interpretation of that laboratory test alone with the clinical diagnosis. Results were consistent with the clinical diagnosis in 88.7% of the series. Inconsistent results most frequently occurred with samples for which cholesterol and triglyceride determinations were not made or considered. Quantitative serum values for these substances obtained from another specimen or which had been determined by another laboratory and were not available to our laboratory, were the most common bases for the physician’s conclusion that the laboratory report was incorrect. We conclude that cholesterol and triglyceride should be routinely determined in the laboratory testing for phenotyping of lipoproteinemia. The cholesterol and triglyceride analyses must be performed on the same specimen that is electrophoresed to provide satisfactory accuracy.
Gas-Chromatographic Identification of Urinary Carbohydrates Isolated by Anion-Exchange Chromatography
Authors: Butts W C , Jolley R L 
Published: January 2020

Abstract
More than 40 chromatographic peaks representing carbohydrates have been separated from human urine by a carbohydrate analyzer that makes use of anion-exchange chromatography. Ten of these separated carbohydrates have been identified by gas chromatography of their trimethylsilyl derivatives, which were formed by reaction with N-trimethylsilylimidazole. The borate buffer from the anion-exchange separation was removed from the samples before the derivatives were made. Gas-chromatographic retention data have been determined for 37 carbohydrates, including pentoses, hexoses, hexosamines, disaccharides, and trisaccharides, and are tabulated as methylene unit (MU) values. These various classes of carbohydrates elute within distinct MU regions, generally in the order of increasing molecular weight. More than one peak is obtained for those sugars existing in more than one anomeric form.
Computer Calculation of Serum Protein Electrophoresis, Based on Peak Height Measurements
Authors: Sax Sylvan M , Moore John J 
Published: January 2020

Abstract
A computer program has been written for off-line calculation of relative and absolute percentages of the five serum protein fractions usually seen on cellulose acetate electrophoretograms, with use of manually observed peak heights on densitometer scans. With myeloma-like peaks, both peak height and width at half-peak height must be measured. Routine application of the program saves technician time and decreases the number of large random errors.
Quantification of Serum Inorganic Phosphorus, Phosphatase, and Urinary Phosphate without Preliminary Treatment
Authors: Goodwin Jesse F 
Published: January 2020

Abstract
A direct method has been devised for determining serum and urinary inorganic phosphorus and serum phosphatase activity. Inorganic phosphorus forms a phosphomolybdate complex in the presence of borate. The complex is reduced with ascorbic acid. The resulting suspension is solubilized with carbonate and the absorbance measured at 720 nm. Samples containing low to moderate concentrations of bilirubin may be assayed by the method, and it compares favorably with a p-semidine reduction procedure with use of a TCA filtrate. Alkaline phosphatase values obtained by the method in which a β-glycerophosphate substrate is used compare favorably with a reference method in which p-nitrophenolphosphate is used as a substrate. Citrates, fluorides, nitrites, oxalates, and mannitol do not appreciably affect results obtained by the method.
Estimating Aberrant Homeostasis: Variance in Serum Calcium Concentration as an Aid in Diagnosis of Hyperparathyroidism
Authors: Drach George W , King J Stanton 
Published: January 2020

Abstract
Frank hypercalcemia is diagnostic of hyperparathyroidism; borderline values present a diagnostic dilemma. Serum calcium and phosphorus concentrations were measured on three or more days in three groups of subjects: 13 healthy controls, 13 hyperparathyroid patients, and six recurrent oxalate stone-formers with idiopathic hypercalciuria. Variances in the concentration of each ion for all individuals were compared by a rank-order runs test. Only individual variances in serum calcium concentrations of patients with hyperparathyroidism were significantly greater than individual variances in the other two groups. Excessive day-to-day variance in serum calcium seems to reflect autonomy of parathyroid function, and can be used to help detect hyperparathyroidism. A similar approach may be diagnostically useful in other diseases in which homeostatic feedback control is aberrant.
A Quick Method for Definitively Diagnosing Phenylketonuria by Detection of Urinary o-Hydroxyphenylacetic Acid
Authors: Hackett Theodore N , Bray Patrick F 
Published: January 2020

Abstract
Increased urinary excretion of o-hydroxyphenylacetic acid is a generally accepted sign of phenylketonuria. Most reported methods for measuring this metabolite require 24 h. We describe a procedure for its separation in 90 min by thin-layer chromatography. Thus, essential dietary therapy is speeded.
Diagnosis of a Case of Acute Intermittent Porphyria with the Aid of Thin-Layer Chromatography—Thin-Layer Electrophoresis of Urine
Authors: Samuels Stanley , Veliz Gaston 
Published: January 2020

Abstract
δ-Aminolevulinic acid and porphobilinogen were identified in urine from a patient with acute intermittent porphyria on routine amino acid chromatography. The compounds were well and rapidly separated by a two-dimensional combination of high-voltage, thin-layer electrophoresis and chromatography. Both compounds gave a yellowish color with ninhydrin; the porphobilinogen gave a strong red color when Ehrlich’s reagent was then applied. Such a pattern has not been observed in any blood and urinary amino acid chromatograms from over 900 patients with other conditions, who were receiving a variety of drugs. We consider this a rapid, specific diagnostic aid in cases of acute intermittent porphyria.
A Gas-Chromatographic Method for Separating and Measuring Barbiturates and Glutethimide in Blood
Authors: Fiereck Ermalinda A , Tietz Norbert W 
Published: January 2020

Abstract
A gas-chromatographic method is described for the quantitative determination of 11 barbiturates and glutethimide in blood. The extracted barbiturates are methylated and injected into a 7% DC-200 column. Use of methohexital as the internal standard, as well as the addition of standards to a drug-free sample of blood, compensates for losses and for differences in the distribution coefficient of the individual barbiturates, and makes the procedure highly precise and accurate.
Dithionite Tube Test—A Rapid, Inexpensive Technique for the Detection of Hemoglobin S and Non-S Sickling Hemoglobin
Authors: Nalbandian Robert M , Nichols Bruce M , Camp Frank R , Lusher Jeanne M , Conte Nicholas F , Henry Raymond L , Wolf Paul L 
Published: January 2020

Abstract
An inexpensive, rapid, convenient screening tube test for the detection of hemoglobin S and non-S sickling hemoglobins has been developed, which has a molecular basis. The reagents consist of potassium phosphate, sodium dithionite, and saponin. When sickling red cells are introduced into such a solution, the red cells lyse immediately, the hemoglobin deoxygenates, the beta globin chains of each hemoglobin tetramer are displaced laterally, complementarity of steric fit between interacting hemoglobin tetramers is achieved in accordance with the recently modified Murayama hypothesis for the molecular mechanism of sickling, a nematic liquid crystal system is formed, and in the presence of hemoglobin S or non-S sickling hemoglobins, the system becomes turbid. On addition of urea, those nematic liquid crystal systems dependent upon hydrophobic bonds are dispersed.
Methoxylated Phenyl Benzo-γ-Pyrone Derivatives (Flavonoids) That Highly Inhibit Erythrocyte Aggregation
Authors: Robbins R C , Hammer R H , Simpson C F 
Published: January 2020

Abstract
Methoxylated flavonoids containing one or three to seven methoxyl groups were compared for inhibitory activity on erythrocyte aggregation in vitro. A serial erythrocyte sedimentation procedure was used, in which the compounds are incubated in blood maintained in thermal and flow equilibria. All compounds tested (30 µmol/liter) significantly inhibited erythrocyte aggregation: hesperidin &lt; tri-O-methylapigenin &lt; tetra-O-methylscutellarein &lt; tangeretin &lt; heptamethoxyflavone &lt; nobiletin &lt; sinensetin. The most active compound, sinensetin, contained methoxyl groups at the 3',4',5,6,7 positions. Compounds with fewer methoxyl groups were significantly less active (P &lt; 0.01), as were compounds with additional methoxyl groups at the 3 and 8 positions. On a molar basis, compounds containing five to seven methoxyl groups were several fold more active on erythrocyte aggregation than was low-molecular-weight dextran.
Amino Acid Transport and Mental Retardation
Authors: Gruemer H-D , Grannis G F , Hetland L B , Costantini M L 
Published: January 2020

Abstract
Overlapping transport specificity may permit amino acid concentrations in brain to readjust to a new (lower) equilibrium in a compensatory response to increased concentrations of a "model" amino acid in serum. If this is true for analogous clinical situations, it may help explain the effects of phenylketonuria on mentation.
Automated Determination of Uric Acid, with Use of a Uricase—Peroxidase System
Authors: Gochman Nathan , Schmitz Joan M 
Published: January 2020

Abstract
An automated colorimetric procedure is described for the determination of serum and urine uric acid with improved specificity. Hydrogen peroxide, formed when uric acid is oxidized by uricase, oxidatively couples with 3-methyl-2-benzothiazolinone hydrazone and N,N-dimethylaniline, in the presence of peroxidase, to produce a stable, sensitive indamine dye. The method is reproducible, and the results correlate well with those obtained by a manual spectrophotometric uricase procedure. Also, the automated procedure is resistant to many added reducing substances that cause positive interferences in alkaline phosphotungstate methods.
Evaluation of an Automatic Calcium Titrator
Authors: Alexander Roy L 
Published: January 2020

Abstract
An automatic calcium titrator for determining total serum calcium concentration has been evaluated. The instrument incorporates a motorized buret, a fluorometer, and a digital readout that is responsive to the quenching of the fluorescent calcium—calcein complex by the chelating agent, ethyleneglycol-bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic acid. Analyses made with the calcium titrator were compared with those made with the SMA 12/60 and atomic absorption spectrophotometry. Good correlation was obtained in each instance. Slight hemolysis and bilirubin concentrations near normal did not affect the results; however, increased concentrations of these substances resulted in decreased values. The precision of analysis depends on the technique used in pipetting the sample. A single analysis of 0.1 ml of serum can be completed in 1 to 2 min. With careful analytical technique, precision is good (CV, 0.72%).
Simplified Benzophenone Procedure for Determination of Diphenylhydantoin in Plasma
Authors: Dill Wesley A , Chucot Lucy , Chang Tsun , Glazko Anthony J 
Published: January 2020

Abstract
Diphenylhydantoin (DPH) is extracted from plasma with ethylene dichloride, returned to alkali, and oxidized with permanganate in glass-stoppered test tubes containing a layer of iso-octane. The absorbance of the oxidation product (benzophenone) in the iso-octane layer is measured spectrophotometrically. This procedure eliminates interference by chloroform that is encountered in other methods; highly specialized reflux condensers or distillation equipment is not needed; and the cost of solvents is decreased. The procedure is highly specific; it detects less than 1 µg of DPH per milliliter of plasma, and it is suitable for routine clinical laboratory use.
A Gas Chromatographic Procedure for Determining Estriol in Pregnancy Urine: Evaluation in Two Different Laboratories
Authors: Touchstone Joseph C , Murawec Taras , O’Leary Daniel K , Luha Leida , Mantell Geraldine 
Published: January 2020

Abstract
Satisfactory interlaboratory results were obtained when estriol in pregnancy urine was determined gas chromatographically in two different university laboratories.
Serum Lipid Concentrations in Patients with Coronary Arteriosclerosis Demonstrated by Coronary Arteriography
Authors: Crowley Leonard V 
Published: January 2020

Abstract
The frequency of abnormal serum lipid concentrations in patients with coronary artery disease demonstrated by coronary arteriography was compared with that for normal control subjects and arteriographically normal patients. Triglycerides were supranormal in over half of the patients with demonstrable coronary artery disease, compared with only about a quarter of the subjects in the control group. Incidence of enhanced serum cholesterol was not significantly different in the two groups. These data support the observations of others who found that triglycerides are elevated more frequently than cholesterol in patients with coronary artery disease. Coronary arteriography enables the more precise diagnosis of coronary arteriosclerosis when attempting a correlation of serum lipid concentrations with coronary artery disease. Selection of subjects in this manner avoids the problem of the falsely low incidence of lipid abnormalities seen when patients are included who have normal coronary arteries. Of the subjects in this series in whom coronary arteriography was performed, 23% were found not to have coronary arteriosclerosis. However, patients who have undergone angiocardiographic studies are a highly selected group with special characteristics, and cannot be considered a representative sample of patients with coronary artery disease.
Modification of an Automated Procedure for Serum Cholesterol, which Permits the Quantitative Estimation of Cholesterol Esters
Authors: Siegel A L , Bowdoin B C 
Published: January 2020

Abstract
Changes are described in AutoAnalyzer Methodology N-24a, for the automated determination of serum total cholesterol, that increase the reaction temperature of the mixture of sample and acid color reagent. The modified procedure eliminates the inaccuracies that attended the original methodology and allows the cholesterol ester moiety in the serum total cholesterol to be quantitated.
Electrophoretic Separation on Agarose Thin Film of Isoenzymes of Alkaline Phosphatase from Human Serum and Tissue
Authors: Demetriou J A , Beattie J M 
Published: January 2020

Abstract
An electrophoretic method is presented for separating alkaline phosphatase isoenzymes on agarose gel by using barbital buffer. α-Naphthyl AS-MX phosphate was converted to the highly fluorescent α-naphthol AS-MX, to detect the zones of enzymic activity on the thin film. The fluorescent zones on the electropherograms were scanned with a recording fluorometer and the electrophoretic mobilities of the enzymes were compared with those of the plasma proteins. This method was used to assess the isoenzyme patterns in human sera and tissues (liver, bone, kidney, spleen, and placenta).
Fluorometric Method for Quantitatively Estimating Urinary Dihydroxyphenylethylamine (Dopamine), Dihydroxyphenylalanine (Dopa), and Dihydroxyphenylacetic Acid (Dopac)
Authors: Eichhorn Friedl , Rutenberg Ada , Kott Edna 
Published: January 2020

Abstract
A relatively simple, exact method is described for simultaneously estimating dopamine, dopa, and dopac in urine. The compounds are concentrated on alumina by an abbreviated batch technique and separated by "two solutions" paper electrophoresis at low voltage for 2 h. Fluorophores are developed by condensation with ethylenediamine. The fluorescent bands, eluted into water, are measured fluorometrically. This method was used to estimate the major free metabolites of dopa in urines from parkinsonian and hyperkinetic patients, and normal subjects. Compared with normal controls, dopamine excretion tended to be decreased in patients with parkinsonism, increased in hyperkinetic patients. The sum of the free metabolites (dopamine, dopac, and homovanillic acid) was significantly smaller for the patients with parkinsonism than for normal subjects.
Biological Applications of the Carbon Rod Atomizer in Atomic Absorption Spectroscopy
Authors: Matoušek Jaroslav P , Stevens Brian J 
Published: January 2020

Abstract
A new technique in atomic absorption spectroscopy is described, which replaces the use of a flame. Samples are injected into a cavity drilled transversely through a carbon rod, and subsequently dried, ashed, and atomized by the application of electric current. The resulting brief absorption signal is recorded and compared with standards. The procedure is particularly suitable for biological work since sample volume requirements are in the submicroliter range. The samples require no pretreatment. The method has given excellent results initially when applied to the measurement of magnesium, iron, copper, lead, and zinc in blood and plasma.
Enhanced Excretion of Free Amino Acids by Hyperthyroid Patients
Authors: Felts John H , King J Stanton 
Published: January 2020

Abstract
Greater than normal amounts of one or more amino acids were found in the urines of 20 of 24 thyrotoxic patients. The amino acids most commonly increased were tyrosine (in nine of the 24 patients), β-aminoisobutyric acid (11/24), and cystathionine (12/24); seven patients had concurrent increases in the latter two amino acids. Hyperaminoacidemia, accompanied by generalized hyperaminoaciduria, was seen in the three nonfasting patients whose urine was examined. Sera from patients fasted overnight contained normal concentrations of free amino acids. Urinary calcium exceeded 250 mg/24 h in 10 of the 24 patients; urinary phosphorus exceeded 1.2g/day in four. These variables correlated poorly with each other, with the diagnostic impression of severity, and with the results of thyroid-function tests.
Ultramicrodetermination of Plasma Urea by Reaction with Diacetylmonoxime—Antipyrine without Deproteinization
Authors: Ceriotti Giovanni 
Published: January 2020

Abstract
Urea can be directly determined in serum or plasma by reaction with diacetylmonoxime—antipyrine: 5 µl of the sample is mixed with 5 ml of the chromogenic reagent, and the mixture is boiled 15 min, cooled, and read at 460 nm. The color is stable for 30 min in the light. The reagent is composed of (a) 0.4 g of antipyrine per 100 ml of H2SO4 (20 ml/100 ml), containing 5 mg of ferric sulfate per 100 ml: 1 (or 2) volume(s), and (b) 0.5 g of diacetylmonoxime per 100 ml of acetic acid (5 ml/100 ml): 1 volume.
Effects of Phenyl Benzo-γ-Pyrone Derivatives (Flavonoids) on Blood Cell Aggregation: Basis for a Concept of Mode of Action
Authors: Robbins R C 
Published: January 2020

Abstract
Flavonoids were investigated for activity on blood cell aggregation. A procedure for measuring serial erythrocyte sedimentation rate (ESR) was used to test the effect of five flavonoids (hesperidin, quercetin, rutin, tangeretin, and naringin) on aggregation in vitro. The activity of the flavonoids was compared with that of quinine and low molecular weight dextran (LMD), both of which demonstrably decrease blood cell aggregation in vivo and in vitro. At a blood concentration of 50 µmol/liter the flavonoids, quinine, and LMD all showed significant effects (P &lt; 0.05) on aggregation, the order of retardation of ESR being rutin &lt; quercetin &lt; LMD &lt; hesperidin &lt; quinine &lt; tangeretin. Naringin-treated blood had a higher ESR than control blood. The effect of flavonoids on blood cell aggregation suggests how they may act against increased capillary permeability and fragility, reduce symptoms in disease, and protect against effects of various traumas and stresess.
Modified Fluorometric Method for Determining Plasma Catecholamines
Authors: Sapira Joseph D , Klaniecki Thelma , Rizk Margaret 
Published: January 2020

Abstract
Plasma catecholamines were fluorometrically determined by a modification of the standard alumina-trihydroxyindole method in which radioactive tracer catecholamines are used to follow the chromatographic behavior of the endogenous catecholamines on alumina. This modification permits appropriate fluorometry of that portion of the eluate with the highest concentration of catecholamines, because incomplete elution of the total endogenous catecholamines can be corrected by use of the isotope recovery data. Additionally, a low column blank was obtained; this method of blank preparation may have obviated some of the known difficulties associated with unoxidized and incomplete plasma blanks that have traditionally been used.
Quantitative Immunoelectrophoresis of Proteins in Serum from a Normal Population: Season-, Age-, and Sex-related Variations
Authors: Lyngbye Jørgen , Krøll Jens 
Published: January 2020

Abstract
By use of a quantitative immunoelectrophoretic method, we have determined the concentrations of 15 serum proteins in 260 normal subjects, 8 to 95 years old. An increase with age was found for haptoglobin and IgA, the opposite being the case for albumin and transferrin. For prealbumin, orosomucoid, α1-lipoprotein, α1-antitrypsin, ceruloplasmin, α2-HS-globulin, β1C-β1A-globulin, plasminogen, IgG, and IgM only lesser changes with age were seen in adults. The α2-macroglobulin concentration decreased markedly until the age of 50, after which there was some increase. Sex-associated differences were seen for albumin, orosomucoid, α1-lipoprotein, α1-antitrypsin, α2-macroglobulin, transferrin, β1C-β1A-globulin, and the immunoglobulins although not in all age groups. There were opposite and highly significant seasonal variations in ceruloplasmin and α2-HS-globulin concentrations.