bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of 14CO2 in breath and 14C in stool after oral administration of cholyl-1-[14C]glycine: clinical application.
Authors: Roda A , Roda E , Aldini R , Mazzella G , Festi D , Sama C , Barbara L 
Published: January 2020

Abstract
Twenty patients with intestinal bacterial overgrowth and 20 control subjects were investigated for bile acid deconjugation, by measuring 14CO2 in the breath after cholyl-1-[14C]glycine administration. 14CO2 output/24h was 11.0 +/- 5.2% (mean +/- SD) in controls and 54.2 +/- 14.0% (mean +/- SD) in bacterial-overgrowth patients (P less than .001). 14CO2 excretion rate in 12h, when normalized to 100% of the dose at the 12th hour, gave an even finer discrimination between the two groups (no false responses). 14C in stool, analyzed in 20 malabsorption patients and 20 controls by two different techniques, was 6.6 +/- 4% and 31.38 +/- 21.7% (mean +/- SD), respectively. Results by the two different techniques described here correlated well (r = .99). Bile acid malabsorption was in reasonable agreement (r = .67) with percentage of "chenoid" (chenodeoxycholic acid plus ursodeoxycholic acid) in the stool by gas-liquid chromatography; a poorer correlation was observed when "chenoid" plus "choloid" (cholic acid plus its epimers) were plotted vs. -4C in stool (r = .57, n = 15).
Determination of urinary total phenolic compounds with use of 4-aminoantipyrine: suggested screening test for hyperthyroidism and for catecholamine-producing tumor.
Authors: Yamaguchi Y , Hayashi C 
Published: January 2020

Abstract
We describe a method for determining those urinary total phenolic compounds that are tyrosine analogs or metabolites, such as thyroxine and catecholamines. The urine sample, 4-aminoantipyrine in carbonate-bicarbonate buffer, and potassium ferricyanide solution are mixed and the quinoneimine dye that forms is measured at 500 nm. Some cases of hyperthyroidism, diabetes mellitus, nephrosis, obesity, hypertension, or catecholamine-producing tumor showed above-normal values, so that this determination seems useful as a screening test for these disorders.
A method for serum octanoate in hepatic cirrhosis and hepatic encephalopathy.
Authors: Rabinowitz J L , Staeffen J , Aumonier P , Ballan P , Ferrer J , Terme R , Series C , Myerson R M 
Published: January 2020

Abstract
We describe a new, more efficient, and more reproducible method for determination of octanoate in serum. This method involves ethanol extraction, followed immediately by alkali addition before concentration of the extract. The concentrate is made acidic only before it is to be steam distilled (in a special all-glass apparatus with an alkali trap). The material is acidified again just before separation by gas-liquid chromatography. The yield is 89-107%. When assayed by mass spectrometry, only octanoate was found in the fraction from chromatography. Previous methods yielded only 30-55% of the expected octanoate value and the recovered materials showed impurities by mass spectrometry. Octanoate concentrations were determined in the serum of 24 fasting controls and that of 85 fasting cirrhotic patients, of whom 50 had encephalopathy. Concentrations in arterial and venous blood were significantly higher in cirrhotic patients in coma than in those not in coma, and arterial concentrations were statistically higher than venous concentrations in the cirrhotic patients.
Mechanisms of cellular enzyme release. II. Inhibition of sarcolemmal enzymes by myopathy-inducing agents.
Authors: Verrill H L , Gruemer H D , Baba N 
Published: January 2020

Abstract
A defective membrane mechanism has been suggested [Arch. Neurol. 33, 315 (1976)] for the pathogenesis of Duchenne muscular dystrophy. The characteristic clinical and biological findings, including leakage of cellular enzymes into the serum in the disease, have been duplicated by the imipramine/serotonin rat myopathy model. Sarcolemma was prepared from quadriceps femoris muscles of control and myopathy-affected animals. The activities of sarcolemmal adenosinetriphosphatase and acetylcholinesterase were inhibited in vitro by imipramine and serotonin. The inhibition by imipramine of these sarcolemma-bound enzyme systems decreased the Vmax and increased the Km. This mixed type of inhibition is consistent with an imipramine-induced interference at these enzyme sites and a disruption of lipid-protein interrelations. We hypothesize that such conformational membrane changes might contribute to the leakage of macromolecules such as enzymes from the cell interior.
Urinary 3-methoxy-4-hydroxyphenylacetic (homovanillic) and 3-methoxy-4-hydroxymandelic (vanillylmandelic) acids: gas-liquid chromatographic methods and experience with 13 cases of neuroblastoma.
Authors: Brewster M A , Berry D H , Moriarty M 
Published: January 2020

Abstract
We present a quantitative gas-chromatographic method for determining urinary 3-methoxy-4-hydroxymandelic acid (vanillylmandelic acid) and 3-methoxy-4-hydroxyphenylacetic acid (homovanillic acid). In this rapid technique an internal standard is used and the procedure involves ether extraction and silyl ether formation. Analytical recovery of vanillylmandelic acid averages 87.5% (CV, 0.95%), of homovanillic acid 102.3% (CV, 9.95%). Our data on 34 samples from 13 neuroblastoma patients show that homovanillic acid is more consistently elevated than is vanillylmandelic acid.
Microdetermination of plasma ATP and creatine phosphate concentrations with a luminescence biometer.
Authors: Jabs C M , Ferrell W J , Robb H J 
Published: January 2020

Abstract
We optimized conditions for determination of adenosine-5'-triphosphate (ATP) and creatine phosphate from plasma extracted with ethanol/water (96/4 by vol). The procedures utilize the firefly luciferin/luciferase reaction, the bioluminescence being measured with a Du Pont Biometer. ATP is quantitated directly and creatine phosphate is quantitated by reaction with creatine kinase and ADP, after plasma ATP is removed by incubation with the enzyme apyrase. The method is applied to plasma from humans, rabbits, and rats, and possible clinical applications are discussed.
Improved hydrolysis of urinary 17-hydroxycorticosteroid glucuronides with beta-glucuronidase from Helix pomatia, on adding sodium sulfate.
Authors: Nishikaze O , Kobayashi T 
Published: January 2020

Abstract
Sodium sulfate increases the hydrolysis of urinary 17-hydroxycorticosteroid glucuronides with beta-glucuronidase preparations derived from Helix pomatia because it removes the inhibitory activity of urinary high-molecular-weight substances. For maximum hydrolysis of urinary 17-hydroxycorticosteroid glucuronides, the hydrolysis [5 ml of urine, 0.5 ml of 2 mol/liter acetate buffer (pH 5.0)] should be conducted in the presence of sodium sulfate (final concentration: 80 g/liter) with (a) 600 Fishman units of the enzyme per milliliter of urine (18 h at 52 degrees C) or (b) with 1500 units of the enzyme per milliliter of urine (3 h at 57 degrees C). Under conditions a, analytical recovery of steroid glucuronides added to 12 urine samples was 99 +/- 2.1% (96-102%). Values obtained for 20 urine samples with this method were 99 +/- 2.7% (93-104%) as great as those yielded by a method in which 600 units of the enzyme from bovine liver are used together with sodium sulfate (18 h at 48 degrees C).
Use of saliva in therapeutic drug monitoring.
Authors: Horning M G , Brown L , Nowlin J , Lertratanangkoon K , Kellaway P , Zion T E 
Published: January 2020

Abstract
We measured the concentrations of phenobarbital, phenytoin, primidone, ethosuximide, antipyrine, and caffeine in paired samples of saliva and plasma by gas chromatograph-mass spectrometer-computer (GC/MS/COM) and enzyme immunoassay. Mixed saliva was collected for the antipyrine and caffeine studies, parotid saliva for the phenobarbital, primidone, ethosuximide and phenytoin studies. The saliva/plasma (S/P) ratios (by weight) obtained by GC/MS/COM were: phenobarbital, 0.31-0.37; phenytoin, 0.11; ethosuximide, 1.04; antipyrine, 0.83-0.95; caffeine, 0.55. The S/P ratio obtained by enzyme immunoassay were: phenobarbital, 0.32; phenytoin, 0.12; primidone, 0.85. The concentrations of phenytoin, primidone, ethosuximide and antipyrine in saliva correspond to the free fraction of the drug in plasma. When we analyzed samples containing phenobarbital or phenytoin (plasma or saliva) by both techniques, we found that the enzyme immunoassay values were generally higher than GC/MS/COM values, suggesting that the metabolites as well as the parent drug were measured in the immunoassay.
Automated system for infrared spectrometric analysis for total CO2 of plasma contained in capillary tubes.
Authors: Rabinow B E , Geisel A , Webb L E , Natelson S 
Published: January 2020

Abstract
We describe how to assay plasma total CO2 automatically, discretely, and highly specifically by infrared absorption spectrometry. Plasma, 50 mul, is sampled in disposable capillaries and inserted into a block wherein the specimens are protected from exposure to air. A sequencer advances the block and signals a dispenser to flush the sample into a reaction vessel with 2.6 ml fo 50 mmol/liter H2SO4. After 24 s of incubation, the evolved CO2 is swept into a 1-meter infrared gas cell by a stream of nitrogen. A recorder displays the resulting peak in absorbance units. Operation of all valves controlling gas and liquid flow is regulated by the sequencer. In the present version, the time required for analysis of one sample is 65 s. The sample size may be reduced by at least 10-fold and the time sequence accelerated to assay 70-80 specimens per hour.
Two-dimensional immunoelectrophrophoretic pattern of low- and very-low-density lipoproteins, with particular reference to Fredrickson's type III.
Authors: Rerabek J E 
Published: January 2020

Abstract
I report the pattern of low-density lipoproteins (LDL) and very-low-density lipoproteins (VLDL) as revealed by two-dimensional (crossed) immunoelectrophoresis in hyperlipoproteinemia types, II, III, and IV, preliminarily diagnosed by means of a complex lipoprotein profile examination. The higher affinity of Oil Red stain for VLDL- than for LDL-immunoprecipitation zones is peculiar to this lipoprotein class, and crossed immunoelectrophoretograms may thus be helpful for laboratory diagnosis of types IIb and IV in problematic cases. The position and the medium affinity for Oil Red of "broad beta" zones appearing in immunoelectrophoretograms of type III hyperlipoproteinemia are suggested as useful criteria for the diagnosis of this condition. From the structural and staining characteristics of VLDL-immunoprecipitation zones, alteration of both composition and antigenic properties of VLDL in hyperlipoproteinemias IIb-IV is deduced. I present in detail the procedure for crossed immunoelectrophoresis as well as that for the lipoprotein profile examination used in this study.
New, advantageous approach to the direct radioimmunoassay of cortisol.
Authors: Tilden R L 
Published: January 2020

Abstract
Radioimmunoassay of serum cortisol is simplified by a unique solution to the problem of eliminating competition between cortisol-binding globulin and cortisol immunoglobulin. Increasing incubation temperature tends to release cortisol from its carrier protein while favoring the immunoglobulin reaction. We applied this methodology, using reagents supplied as a commercial kit. Serum, 5 mul, is diluted with 125I-containing(hydroxymethyl)aminomethane buffer and incubated at 45 degrees C for 1 h, then aspirated. All standards are constituted in steroid-deprived serum. The clinical validity of the method is supported by comparisons with conventional methods during months of use under routine laboratory conditions. The simplified method also offers improved performance characteristics and, as described, if fully instrumented. The significance of this use of thermodynamic properties is discussed in terms of more general applicability.
Total lactate dehydrogenase and its isoenzymes in serum in the presence of penicillamine and other sulfhydryl compounds.
Authors: Gershbein L L , Raikoff K G 
Published: January 2020

Abstract
Toward delineation of changes in total lactate dehydrogenase (LDH) and in the distribution of LDH isoenzymes as assessed by polyacrylamide disc electrophoresis, we inbucated human and rat sera with various agents, notably sulfhydryl compounds. Although artefacts were apparent when these agents were used without preliminary adjustment of pH, we saw little alteration in total unitage when one or two volumes of serum was mixed with one volume of any of several thiols, especially penicillamine, at an initial concentration of 0.4 mol/liter and pH 7.0-7.5. Under these conditions, penicillamine caused a loss in LDH-5 after incubation for 1 h at 25 degrees C together with small decreases in mobility of the other four isoenzymes toward the anode. A zymosan region appeared below the albumin and tracking dye area. With longer periods of incubation of rat serum with penicillamine or alpha-mercaptosuccinate, a novel band in the zymogram was noted just above the LDH-4 peak. The observations are discussed in terms of allosteric effectors.
Fluorometric estimation of triglycerides in serum by a modification of the method of Bucolo and David.
Authors: Rietz E B , Guilbault G G 
Published: January 2020

Abstract
An enzymic, flurometric method is described for determination of triglycerides (and glycerol) in blood serum, a modification of the method of Bucolo and David [Clin. Chem. 19, 476 (1973)]. Commercially available reagent kits are used. The rate of disappearance of NADH fluorescence at 460 nm (excitation wavelength, 365 nm) is monitored and related to serum triglyceride concentration, corrected for the content of free glycerol. We compared the results obtained fluorometrically to the ultraviolet spectrophotometric Boehringer Neutral Fat method used at Gentofte Hospital, Copenhagen. Instrument response and concentration were linearly related in the range 0.27 to 2.7 mmol of triglycerides per liter of serum with the fluorometric method. The CV was 0.9% for the fluorometric method, 3.7% for the spectrophotometric procedure. The fluorometric method requires less reagents, time, and calculations than does the spectrophotometric method.
Urinary free norepinephrine and dopamine determined by reverse-phase high-pressure liquid chromatography.
Authors: Mell L D , Gustafson A B 
Published: January 2020

Abstract
We used reverse-phase high-pressure liquid chromatography to measure free norepinephrine and dopamine simultaneously in human urine. Samples were treated with alumina, and the catecholamine(s) then eluted from it were directly injected onto a reverse-phase column (octadecyl-silica stationary phase), with 0.17 mol/liter acetic acid as the mobile phase and ultraviolet detection at 280 nm. The assay detects concentrations in urine as low as 5 mug/liter. Assay of 24-h urines (n = 10) gave within-run and day-to-day coefficients of variation of 3.7 and 4.7% for norepinephrine, and 2.6 and 3.5% for dopamine, respectively. Comparison studies with the traditional trihydroxyindole fluorometric method showed the liquid-chromatographic procedure to be more precise and subject to less interference. This relatively rapid procedure for urinary free norepinephrine and dopamine provides an efficient, reproducible method, readily adaptable to routine clinical use.
Interference of sodium azide with measurement of serum uric acid by the direct acid ferric reduction procedure.
Authors: Liu T Z , Khayam-Bashi H 
Published: January 2020

Abstract
We examined the effect of sodium azide on the quantitation of serum uric acid by the direct acid ferric reduction procedure. Ferric phenanthroline was used as redox indicator. Sodium azide, in a concentration commonly used as preservative (2 g/liter, 27.2 mmol/liter), increased the absorption at 505 nm and increased apparent uric acid values in specimens, as shown by calculations based on an azide-free standard. Spectral studies indicated that this interference was a result of the color produced by sodium azide in the reaction mixture. The mechanism for azide interference was the interaction of sodium azide and ferric ions to form ferric azide, which also absorbs extensively at 505 nm.
Micro-scale anticonvulsant assay with use of nitrogen/phosphorus detector and on-column methylation compared with a macro-scale procedure involving flame-ionization detection.
Authors: Least C J , Johnson G F , Solomon H M 
Published: January 2020

Abstract
We report a modified micro-scale gas-chromatographic procedure for determining phenobarbital, primidone, and diphenylhydantoin in serum with use of a nitrogen/phosphorus detector. Serum, 20 mul, is extracted into chloroform, the solvent is evaporated, and the residue dissolved in dilute (32 mmol/liter) trimethylanillinium hydroxide, which yields the methyl-derivatives of the drugs upon on-column injection. Within-run precision (CV) for the three drugs was 1.0, 2.1, and 1.4+, respectively, at concentrations of 19.2, 13.2, and 18.9 mg/liter; run-to-run precision at these concentrations was 4.4, 3.8, and 2.8%. Comparison of the 20-mul micro-scale procedure (y) with our conventional, flame-ionization macro-scale procedure (x), in which on-column methylation is used and which requires 1 ml of serum, gave the following respective results: y = 1.01 X -- 0.16 mg/liter, r = 0.992, y = 1.02 X + 0.29 mg/liter, r = 0.973; and y = 0.96x + 0.04 mg/liter, r = 0.996.
Diagnostic Effectiveness of Biochemical Liver-Function Tests, as Evaluated by Discriminant Function Analysis
Authors: Sher Paul Phillip 
Published: January 2020

Abstract
I evaluated the diagnostic value of routinely ordered liver-function tests in 175 biopsy-proven cases of hepatic disease by use of stepwise discriminant analysis. The tests studied—total and "direct" bilirubin, alkaline phosphatase, lactate dehydrogenase, and aspartate aminotrans-ferase—correctly classified 45-73% of cases, depending on the homogeneity of the diagnostic groups. Aspartate aminotransferase and alkaline phosphatase were the best discriminators. When all tests were used in the most ho-mogeneous groups (tumors, cirrhosis, and hepatitis), there was a stepwise improvement in diagnostic accuracy from 51 to 73%.
Separation of Tissue and Serum Acid Phosphatase lsoenzymes by Ion-Exchange Column Chromatography
Authors: Mercer Donald W 
Published: January 2020

Abstract
I describe a simple, rapid ion-exchange column-chroma-tographic technique for separating the acid phosphatase (EC 3.1.3.2) isoenzymes in human serum and tissue. Ex¬tracts of platelets, spleen, liver, erythrocytes, and prostate were used to determine optimum conditions for separating these isoenzymes. Samples layered on mini-columns of DEAE-Sephadex A-50 were eluted stepwise with sodium chloride (100, 200, and 300 mmol/liter, buffered with tris(hydroxymethyl)aminomethane). Activity in column effluents was measured with p-nitrophenol phosphate as substrate, and their isoenzyme content was assessed by electrophoresis on polyacrylamide gel. Comparison of activity patterns so derived for various tissues revealed prostatic tissue to be a rich source of acid phosphatase isoenzyme 2 activity. Evaluation of sera from six patients with prostatic cancer revealed isoenzyme patterns with prominent amounts of isoenzyme 2 (3.8 to 27.6 U/liter). Sera from 10 healthy laboratory technicians contained isoenzyme 2 in the range of 0.3-0.5 U/liter. Samples from two patients with abnormally high activity owing to non¬prostatic conditions (Gaucher's disease and carcinoma of lung) exhibited less than 2 U of isoenzyme 2 per liter and acid phosphatase isoenzymes 3-5 that were 50- to 100-fold the normal range. Quantification of isoenzyme 2 by DEAE-Sephadex column chromatography as de¬scribed appears to provide a more sensitive and specific approach to diagnosis of prostatic cancer.
New Approach to Evaluation of Proteinuric States
Authors: Ellis Demetrius , Buffone Gregory J 
Published: January 2020

Abstract
We evaluated the use of immunonephelometric methods for measuring specific urinary proteins. Using a nephe¬lometer to detect light scattering (angle, 31'1, we mea¬sured some proteins immunonephelometrically in serum and aliquots of 24-h urines from 50 apparently healthy children, ages 2-17 years. The mean urinary excretion rate (mg/24 h) and the range of values was: for albumin 5.5 (range, 0-13.3), for transferrin 0.5 (0-1.9), for IgG 3.3 (0-12), and for a2-macroglobulin 0.6 (0-2.3). Direct comparison of the values for pathological urines with those for a reference population may offer more meaningful information concerning the integrity of the glomerular basement membrane than is provided by protein selectivity indices, and measuring a plasma protein such as albumin in urine may better define pathological proteinuria.
A Radioimmunoassay for Serum Ferritin
Authors: Luxton Allan W , Walker William H C , Gauldie Jack , Ali Mahmoud A M , Pelletier Catharine 
Published: January 2020

Abstract
We describe the development and evaluation of a serum ferritin radioimmunoassay, in which 125l-labeled ferritin and rabbit anti-ferritin antibody are used. Goat anti-rabbit gamma-globulin antibody, together with polyethylene glycol, is used as the separating reagent. The assay has a working range up to 500 µg of ferritin per litre, and a sample requirement of 75 µl of serum for assay at two dilutions. The assay requires 24 h. It has a sensitivity of 1.5 ,ug of ferritin per litre and a long-term precision (CV) of 13%. Reference intervals for a population of men were 18-330 µg/litre, with no marked age dependence, while those for a population of women older than 50 years were 18-200 Agate. Many apparently healthy women in the 20-50 year age group have much lower concentrations. Serum ferritin concentrations of &lt;18 Agilitre are indicative of iron deficiency, defined as the absence of stainable iron in an aspirate of bone marrow.
Evaluation of a New Automatic Calcium Ion Analyzer
Authors: Madsen SØren , ⵁlgaard Klaus 
Published: January 2020

Abstract
We evaluated a new automatic analyzer for ionized cal¬cium (Ca2+), the Orion Model SS-20, based on a flow-through ion-exchange electrode. Ca2+ was measured in heparinized whole blood and serum. Within-day variation was 1.2%, day-to-day variation 1.6 %, and analytical re-covery 92.4%. Over the physiological range interference by K± and Mg2+ was negligible; major changes in ionic strength, induced by changes in Na+ concentration, made correction for a sodium error necessary. Within the physiological range, Ca2+ was inversely correlated to variations in pH. Therefore, to compare Ca2+ values, correction to an apparent pH of 7.40 should be made. The calcium binding effect of heparin was negligible when minimal (4.4 int. units/m1) concentrations of heparin were used. Storage of serum at 4 °C for one week resulted in a 4% decrease in apparent serum Ca2+, primarily owing to an increase in pH during storage. In normal material, mean values for blood- and serum-Ca2+ (1.10 and 1.07 mmol/liter, respectively) were close to results obtained by previous systems. Errors caused by disturbances in the fluid flow and non-function of half the electrodes we re¬ceived were the major inconveniences of the analyzer. We conclude that this new analyzer gives decisive advantages in measurement of Ca2+, making this important analysis possible as a routine laboratory test for the first time