bluuebunny/crossref_metadata_2025_split huggingface dataset:
In situ monitoring.
Authors: Hicks J M 
Published: January 2020

Abstract
In situ monitoring has been increasingly accepted during the past five years. This approach has been applied to measurement of gas tensions such as pO2 and pCO2, to pH and ions, to the assessment of jaundice by measurement of bilirubin, and to analysis for 14CO2 after administration of labeled antipyrine and aminopyrine, for evaluation of hepatic damage. Various techniques have been developed for in situ monitoring: transcutaneous measurements, implantable sensors, ingestible radio-sensitive pills, and breath analysis. Here I review some of these approaches and their limitations. These limitations include the sparsity of circumstances under which the technique can be applied and the probable increase in health-care costs.
Hypercholinesterasemia with isoenzymic alteration in a family.
Authors: Hada T , Yamawaki M , Moriwaki Y , Tamura S , Yamamoto T , Amuro Y , Nabeshima K , Higashino K 
Published: January 2020

Abstract
A family with hypercholinesterasemia with isoenzymic alteration is reported. The propositus, a 55-year-old woman, was admitted to our hospital because of diabetes mellitus. Because her cholinesterase activity (delta pH 3.2) was supranormal, with no other abnormal liver-function test result throughout the hospitalization period, and was independent of her disease state, we investigated whether this condition might be familial. We studied six of her 17 family members in three generations. All six had above-normal serum cholinesterase activity. Gradient gel electrophoresis on polyacrylamide showed that the normal control individuals had seven isoenzymes, but all the family members with hypercholinesterasemia had two additional isoenzymes. The enzymic properties of the affected members were similar to those of the normal individuals. Hypercholinesterasemia in this family seems to be the result of an increased number of enzyme molecules, but how this isoenzymic alteration emerged remains obscure.
Improved estimation of fructosamine, as a measure of glycated serum protein, with the Technicon RA-1000 analyzer.
Authors: San-Gil F , Schier G M , Moses R G , Gan I E 
Published: January 2020

Abstract
We present an improved fructosamine assay for use with the Technicon RA-1000 analyzer. Features of this assay include: specimen throughput of 100 per hour, within-batch CV of 1.5%, between-batch CV of 2.4%, standard curve linear up to 24.9 mmol of fructosamine per liter, and good correlation (r = 0.82) with hemoglobin A1.
Amplified flow-cytometric separation-free fluorescence immunoassays.
Authors: Saunders G C , Jett J H , Martin J C 
Published: January 2020

Abstract
An equilibrium-type competitive-binding fluorescence immunoassay with high sensitivity and excellent precision is described that obviates separation of free from bound label. In the assay relatively large (10 microns diameter) antibody-coated non-fluorescent particles and very small (0.10 micron diameter) antigen-coated fluorescent latex particles are used. Soluble nonlabeled antigen competes with antigen on the microspheres for antibody binding sites on the larger spheres. After equilibrium is attained, the fluorescence distribution of 5000 of the large spheres is measured in a flow cytometer. The mean values for the fluorescence distribution obtained from samples containing known concentrations of soluble antigen are used to construct a standard displacement curve. In a prototype assay for the antigen horseradish peroxidase, a sensitivity of 10(-12) mol/L has been achieved. Undiluted serum can be assayed without loss of sensitivity. Preliminary experiments also indicate that double-antibody "sandwich"-type assays of very high sensitivity (10(-14) mol/L) are also possible when this dual-sphere concept is exploited.
Single-cuvet sequential determination of triglyceride and cholesterol.
Authors: Zoppi F 
Published: January 2020

Abstract
I describe a sequential method for kinetic assay of serum triglyceride and cholesterol in a single cuvet. Triglyceride is assayed first, by an ultraviolet enzymic method with ATP and NADH as the driving reagents (Clin Chem 21:1627-1629, 1975); cholesterol is then assayed with use of cholesterol oxidase, peroxidase, and the Trinder reaction. Excess NADH left by the triglyceride assay is removed by adding either pyruvate or glycerol to the cholesterol reagent; the addition prevents interference of NADH with nascent H2O2, and does not affect the apparent Km of cholesterol oxidase or the pseudo-first-order reaction of the cholesterol assay. The method, tested in both a random-access analyzer (Hitachi 705) and a batch analyzer (Olli C/D), at three concentrations, gave the following within-run CVs:3.0, 1.6, 1.5% for cholesterol; 4.0, 4.2, 5.4% for triglyceride. The corresponding between-run CVs were 12.5, 9.0, 8.1% and 12.8, 11.1, 8.9%. The calibration was linear to at least 8.0 g/L for both cholesterol and triglyceride. Interference from bilirubin, hemoglobin, and certain drugs is almost negligible. Correlation studies with reference and routine methods showed r values ranging from 0.985 to 0.995 for cholesterol, 0.984 to 0.991 for triglyceride.
Computer evaluation of statistical procedures, and a new quality-control statistical procedure.
Authors: Blum A S 
Published: January 2020

Abstract
I describe a program for definitive comparison of different quality-control statistical procedures. A microcomputer simulates quality-control results generated by repetitive analytical runs. It applies various statistical rules to each result, tabulating rule breaks to evaluate rules as routinely applied by the analyst. The process repeats with increasing amounts of random and systematic error. Rate of false rejection and true error detection for currently popular statistical procedures were comparatively evaluated together with a new multirule procedure described here. The nature of the analyst's response to out-of-control signals was also evaluated. A single-rule protocol that is as effective as the multirule protocol of Westgard et al. (Clin Chem 27:493, 1981) is reported.
Cholesterol determination in serum after fractionation of lipoproteins by immunoprecipitation.
Authors: Heuck C C , Erbe I , Mathias D 
Published: January 2020

Abstract
We investigated the immunoprecipitation of apolipoprotein B-binding lipoproteins, or of apo A-I- and apo C-binding lipoproteins, by delipidated antiserum for measuring cholesterol in the nonprecipitated lipoprotein fractions. After immunoprecipitation of serum with delipidated anti-apo B, we determined by immunoelectrophoresis that no beta- or pre-beta lipoproteins were present, whereas alpha-lipoproteins remained in the supernate. Conversely, after immunoprecipitation with an antiserum against apo A-I + apo C, only lipoproteins with beta-mobility were detected and no apo B from beta-lipoproteins was in the precipitate. The concentration of cholesterol in the supernate after immunoprecipitation with anti-apo B correlated highly (r = 0.93, n = 118) with cholesterol measured after precipitation with phosphotungstic acid/MgCl2. The cholesterol concentration after immunoprecipitation with anti-apo AI and anti-apo C correlated similarly well (r = 0.94, n = 145) with the LDL-cholesterol calculated by Friedewald's formula in serum specimens reflecting moderate hyperlipoproteinemia.
Effect of storage on measurement of ionized calcium in serum of uremic patients.
Authors: Nikolakakis N I , De Francisco A M , Rodger R S , Gaiger E , Goodship T H , Ward M K 
Published: January 2020

Abstract
We studied, in 70 acidotic and non-acidotic uremic patients, the analytical variance in serum ionized calcium as related to duration and temperature of storage. Storage of serum or whole blood at 4 degrees C for as long as 6 h did not significantly alter the measured concentration of ionized calcium in the serum. Storage at room temperature for 6 h, or longer at 4 degrees C or -20 degrees C, resulted in inaccuracies in 39 to 79% of the samples of serum and in 38 to 92% of the samples of whole blood. These errors were not negated by correcting the values for ionized calcium to a pH of 7.40. Indeed, corrected values for calcium were even more unreliable in acidotic patients. We conclude that samples from uremic patients should be analyzed for ionized calcium within 2 h, or within 6 h if stored at 4 degrees C.
Detection of thyroid disorders by use of basal thyrotropin values determined with an optimized "sandwich" enzyme immunoassay.
Authors: Bernutz C , Kewenig M , Horn K , Pickardt C R 
Published: January 2020

Abstract
To measure the concentrations of thyrotropin (thyroid-stimulating hormone), we used the components of a commercially available two-step "sandwich" enzyme immunoassay (Enzymun-Test TSH, Boehringer Mannheim) based on the specific binding of the beta-subunit of thyrotropin by monoclonal antibodies coated on polystyrene tubes. By modifying the original assay protocol, we lowered the limit of detection to 0.18 milli-int. units/L, using a total incubation period of 22 h. With this modification we could differentiate between patients responsive to administration of thyroliberin (thyrotropin-releasing factor) and those who were non-responders, by measuring only the basal concentration of thyrotropin. Furthermore, we demonstrated a correlation between the basal concentration of thyrotropin and its increase after administration of thyroliberin (r = 0.77, n = 48).
Abnormal lactate dehydrogenase isoenzyme in serum and tumor tissue of a patient with neuroblastoma.
Authors: Otsu N , Hirata M , Miyazawa K , Tuboi S 
Published: January 2020

Abstract
Serum and tumor tissue of a patient with neuroblastoma contained an abnormal isoenzyme of lactate dehydrogenase (LDH; EC 1.1.1.27), which, on agarose gel electrophoresis, migrated between LDH-2 and LDH-3 with a mobility the same as that of the extra LDH isoenzyme found in normal human erythrocytes. On surgical removal of the tumor, the high total LDH activity (775 U/L) in the serum of the patient rapidly decreased to normal (70-220 U/L), and the abnormal LDH isoenzyme was no longer detected. The total LDH activity of the abnormal LDH isoenzyme per gram of hemoglobin in the tumor tissue was 26 times that of erythrocytes, suggesting that the abnormal isoenzyme originated mainly from the tumor cells themselves rather than the erythrocytes contained in the tumor tissue. This first report on the appearance of the abnormal LDH isoenzyme in a patient with neuroblastoma suggests that this abnormal LDH isoenzyme may have some significance as a marker enzyme for neurogenic tumors.
Mixed acid-base disorders.
Authors: Walmsley R N , White G H 
Published: January 2020

Abstract
Mixed acid-base disorders, the occurrence of two or more primary acid-base disturbances in the same patient, are common in the hospital population, but are usually misdiagnosed because of lack of knowledge of the consequences of the primary disturbances. This paper describes seven examples of these disorders recently seen in the authors' hospital, and provides a logical approach to their diagnosis.
Effect of bias in hematofluorometer measurements of protoporphyrin in screening programs for lead poisoning.
Authors: Mitchell D G , Doran D 
Published: January 2020

Abstract
Values for erythrocyte protoporphyrin (EP), measured in our laboratory after extraction with ethyl acetate-acetic acid, were compared with hematofluorometer measurements made in 21 other laboratories. We found that: (a) for samples of patients' blood, hematofluorometer results were 11 to 28% lower than the extraction-based values, depending on the concentration of EP and the mathematical model used; (b) hematofluorometers had mean errors of 0 to 3% for federal proficiency-testing samples; (c) there were no performance differences between fresh and shipped blood for the six laboratories that were analyzing both; (d) a hematofluorometer with a 20% low bias at an EP concentration of 500 micrograms per liter of whole blood (by the extraction method) will not detect about a third of the children whose EP concentration exceeds that cutoff value; and (e) at this same cutoff value for EP, the extraction tests detects about 45% of children whose blood lead exceeds 300 micrograms/L, whereas a 20% low-bias hematofluorometer detects only about 37%.
MM subisoenzymes of creatine kinase as an index of disease activity in polymyositis.
Authors: Annesley T M , Strongwater S L , Schnitzer T J 
Published: January 2020

Abstract
Creatine kinase (CK; EC 2.7.3.2), although the most commonly measured enzyme for assessing disease activity in polymyositis, is not always a reliable indicator of the extent and severity of myositis. Recently, the CK-MM isoenzyme has been found to undergo post-synthetic modifications upon release into the serum, such that electrophoretically identifiable sub-bands or subisoenzymes--MM1, MM2, and MM3--are produced. To determine the diagnostic and discriminative value of these subisoenzymes in polymyositis, we analyzed CK and its MM subisoenzyme forms in serum samples from 22 patients with myositis and from 23 controls. In the presence of inflammatory myositis and increased total CK activity, MM-patterns correlated with the clinical trend, often more accurately than did measurements of total CK. MM1 proportions greater than 30% of total CK-MM or ratios of MM3 to MM1 less than 1 were associated with an improving or stable condition, whereas MM1 activity less than 30% or MM3/MM1 greater than 1 reflected a deteriorating course of disease. Patients whose disease was assessed to be clinically deteriorating were clearly distinguished from patients with improving disease by their subisoenzyme patterns (p less than 0.01). Thus these patterns add significantly to the information obtainable by routine blood analysis.
Galactose and galactitol in the urine of children with compound heterozygosity for Duarte variant and classical galactosemia (GtD/gt) after an oral galactose load.
Authors: Schwarz H P , Schaefer T , Bachmann C 
Published: January 2020

Abstract
An oral dose of galactose, 1 g/kg of body weight, was administered to 24 children with the Duarte variant/classical galactosemia genetic compound (GtD/gt) and to 16 controls ranging in age from 0.3 to 10.7 years. Urine was then collected for 3h. Excreted amounts of galactose and galactitol increased with age in all subjects, but were consistently greater in the compound heterozygotes. If related to urinary creatinine, galactosuria and galactitoluria were no longer age-dependent, although as compared with the controls, urinary galactose was about three times and urine galactitol twice as high in the patients (p less than 0.01 for both). We found a statistically significant correlation between urinary galactitol and galactose in these patients. Moreover, urinary galactitol and galactose each correlated positively with the area under the plasma galactose curve, as well as with the peak value for plasma galactose after galactose ingestion.
Human kininogens of low and high molecular mass: quantification by radioimmunoassay and determination of reference values.
Authors: Adam A , Albert A , Calay G , Closset J , Damas J , Franchimont P 
Published: January 2020

Abstract
Kininogens of low and high molecular mass, highly purified from human plasma, were used to raise antisera in rabbits. To obtain immunologically intact tracers, we labeled the kininogens by the lodogen method, followed by double chromatography, first on Sephadex G50 and then on Sephadex G200 for high-molecular-mass kininogen or on G100 for low-molecular-mass kininogen. Both assays are sensitive, accurate, and reproducible. On an equimolar basis, the high-molecular-mass kininogen cross reacted completely in the determination of low-molecular-mass analyte. Moreover, the radioimmunoassay for the former was highly specific. After optimizing the time and temperature of incubation to provide rapid and reliable results, we determined 95% reference intervals from a large sample of healthy subjects (250 men, 200 women): 109-272 and 69-116 mg/L for the low- and high-molecular-mass kininogens, respectively.
Results of dipstick tests, visual inspection, microscopic examination of urine sediment, and microbiological cultures of urine compared for simplifying urinalysis.
Authors: Christenson R H , Tucker J A , Allen E 
Published: January 2020

Abstract
Using microscopic sediment examination, reagent dipsticks, visual appearance, and microbiological culture, we studied 196 urine specimens collected under sterile conditions. We conclude that the sensitivities and specificities noted in the comparison of dipstick urinalysis with urine microscopy justify eliminating many microscopic examinations if a procedural flowchart is used. All 33 (16.8%) of the uncontaminated urine specimens showing substantial potential pathogen content on culture had either a turbid appearance or positive results for one or more dipstick tests. A positive dipstick test result for nitrite most consistently indicated that the urine should be cultured.
Comparison of enzyme immunoassay and immunoprecipitation for creatine kinase MB in diagnosis of acute myocardial infarction.
Authors: Wu A H , Gornet T G , Bretaudiere J P , Panfili P R 
Published: January 2020

Abstract
We compared the clinical performance of measuring creatine kinase (EC 2.7.3.2) isoenzyme MB by use of an enzyme immunoassay (Enzygnost CK-MB, Behring Diagnostics) with an immunoprecipitation method (Isomune-CK, Roche Diagnostics) for the diagnosis of acute myocardial infarction. Sera from 80 patients admitted to the coronary care unit because of chest pain were examined: 40 who had this diagnosis of myocardial infarction, and 40 in whom it was ruled out. In addition, sera from 40 apparently healthy individuals were examined. The clinical sensitivity and specificity of these methods were evaluated by use of receiver operating characteristic curves. We conclude that for clinical efficiency, this enzyme immunoassay is slightly superior to the immunoprecipitation assay we used, because of its greater analytical sensitivity and precision for measuring the mass of the isoenzyme.
An albumin dimer in urine.
Authors: Beilby J P , Chin C , Garcia-Webb P , Bhagat C I 
Published: January 2020

Abstract
An albumin dimer (approximately 134 000 Da) was present, along with monomeric albumin, in freshly voided urine but not in serum from a 53-year-old man with alcoholic liver disease and chronic renal failure. The dimerization, evidently via disulfide bonds, resulted in a loss of [125I]thyroxin-binding capacity. This suggests that the S--S bridging is at a site different from that previously reported. The dimer was unstable at all storage temperatures studied.
Combined Immunochemical and Electrophoretic Determinations of Proteins in Paired Serum and Cerebrospinal Fluid Samples
Authors: Papadopoulos N M , Costello R , Kay A D , Cutler N R , Rapoport S I 
Published: January 2020

Abstract
Vol. 30
p 1814: In this paper the figures were illustrated in the incorrect order. The correct figure order is shown here.
See Images in the PDF file
Improved ultrafiltration method for simultaneous measurement of free thyroxin and free triiodothyronine in serum.
Authors: Wang Y S , Hershman J M , Pekary A E 
Published: January 2020

Abstract
We describe a new ultrafiltration method for measuring concentrations of free thyroxin (FT4) and free triiodothyronine (FT3). Serum containing [131I]T4 and [125I]T3 is diluted 10-fold in phosphate buffer (500 mmol/L, pH 7.4 at 37 degrees C), then passed through a YMT membrane in an Amicon MPS-1 centrifugal ultrafiltration device. Radioactive iodide and protein-bound thyronines are separated from FT4 and FT3 in the ultrafiltrate by use of a Sephadex G-25 microcolumn. In normal controls, the fraction of T4 that passes into the ultrafiltrate is 0.021 +/- 0.006% (mean +/- SD), FT4 is 19.6 +/- 6.5 ng/L, the fraction of T3 that passes into the ultrafiltrate is 0.18 +/- 0.5%, and the FT3 is 2.03 +/- 0.50 ng/L. Intra-assay precision (CV) is 5.4% for FT4 and 4.2% for FT3; the respective interassay CVs are 10.1% and 8.0%. In various groups of patients with thyroid disease and other conditions that influence serum T4 and T3 concentrations, FT4 by ultrafiltration correlated with FT4 measured by equilibrium dialysis (r = 0.84, p less than 0.001) and FT3 by ultrafiltration correlated with FT3 measured by the Diagnostic Products RIA kit (r = 0.87, p less than 0.001). The accuracy, reproducibility, speed, and simplicity of the ultrafiltration method compared favorably with the more cumbersome method of equilibrium dialysis.
Direct potentiometric determination of sodium ion in blood. III. Influence of (bi)carbonate.
Authors: Boink F B , Bijster P , Vink K L , Maas A H 
Published: January 2020

Abstract
We measured the emf of a sodium ion-selective electrode in NaCl-NaHCO3 solutions (160 mmol of Na+, 160-120 mmol of Cl-, and 0-40 mmol HCO3- per liter) with a home-built cell in steady-state after 10 min and with two commercial direct potentiometric analyzers about 20 s after the sample was introduced. Substitution of HCO3- for Cl- resulted in a small decrease in emf. We calculated the effect of chloride ion replacement by bicarbonate ion on the liquid-junction potential and found that this accounted only for one-third of the emf decrease. The exact composition of bicarbonate solutions is closely related to the pH. To control the formation of carbonate, we performed measurements with the home-built cell at two pH values (7.0 and 8.2), controlled by tonometry with carbon dioxide. From the differences in the slope of the emf vs the amount of bicarbonate added at the two pHs we calculated the thermodynamic association constants of the sodium bicarbonate and sodium carbonate complexes (KNaHCO3(0) = 0.53 and KNaCO3- = 24). We conclude that, for the direct potentiometric measurement of sodium ion, only fresh serum should be used, to avoid pH changes. Replacement of sodium chloride by sodium bicarbonate caused different results when emf was measured with commercial analyzers, owing to their short measuring time of about 20 s.
Specificity of autoantibodies to lactate dehydrogenase isoenzyme subunits.
Authors: Podlasek S J , McPherson R A , Threatte G A 
Published: January 2020

Abstract
We studied serum from 12 unrelated patients with variant electrophoretic patterns for lactate dehydrogenase (EC 1.1.1.27; LD) isoenzymes characteristic of LD-immunoglobulin complexes. Immunoglobulin class was identified in four cases. In all 12 cases, mixing the patient's serum with control serum altered the mobility of normal LD isoenzymes to that of the variant. To determine antigenic specificity, we mixed ammonium sulfate-precipitated fractions of patient's samples with purified LD1 (H tetramer) or LD5 (M tetramer) prepared by anion-exchange chromatography. In six cases the fractionated antibody displayed a pure M-subunit specificity. In four cases it acted against both M tetramers and H tetramers, and in two cases the antibody affected the migration only of LD isoenzymes containing both M and H subunits (i.e., hybrid isoenzymes). Depending on the relative excess of antibody or LD5 in such mixtures, various different anomalous electrophoretic patterns were produced. These results indicate that apparent differences between variant LD isoenzyme patterns in whole serum of different individuals can arise from autoantibodies with similar reactivities being present in various ratios of antigen to antibody.
Measurement of urinary chloride with the Kodak Ektachem 400.
Authors: Melhem M F , Seltman H , Sanghvi A 
Published: January 2020

Abstract
Urinary chloride can be measured simply, precisely, and accurately with the Ektachem 400 clinical chemistry analyzer. Because the coated film technique used in this instrument requires the presence of a protein matrix, we added a protein-based calibrator to the urine samples to overcome the low protein concentration in these specimens. Its advantages over a coulometric titration method (Astra analyzer) include the extension of the range of linearity to lower concentrations and the absence of interference from prednisone metabolites in urine. A disadvantage is the negative bias interference of allopurinol.