bluuebunny/crossref_metadata_2025_split huggingface dataset:
Presence of nonesterified and acylcarnitine in human polymorphonuclear leukocytes and mononuclear cells.
Authors: Katrib K , Adlouni H A , Férard G 
Published: January 2020

Abstract
We demonstrate the presence of nonesterified carnitine and acylcarnitine in leukocytes, but not in erythrocytes, from 16 healthy adults. After carefully separating the different kinds of blood cells we measured significant amounts of nonesterified carnitine and acylcarnitine in polymorphonuclear leukocytes (28.5 +/- 6.1 and 18.5 +/- 6.3 mumol/10(9) cells) and mononuclear cells (25.4 +/- 5.2 and 14.8 +/- 4.5 mumol/10(9) cells). We also measured nonesterified carnitine, long-chain acylcarnitine, and short-chain acylcarnitine in plasma after fractionation with perchloric acid and obtained the following values (mean +/- SD): 41.4 +/- 2.6, 3.9 +/- 1.2, and 6.0 +/- 1.6 mumol/L, respectively. The mean percentages of total carnitine (n = 6) in polymorphonuclear leukocytes, mononuclear cells, and plasma were approximately 62%, 27%, and 13% of whole-blood carnitine, respectively (mean recovery was 102%). The percentage of acylated carnitine was 37% in leukocytes, as compared with 19% in plasma.
Rapid detection of leukemia cells by use of a complement-mediated cytolytic reaction and an imaging sensor system.
Authors: Suzuki M , Tamiya E , Kataoka T , Tokunaga T , Karube I 
Published: January 2020

Abstract
We describe a system for detection of leukemia cells involving complement-mediated cytotoxic reaction and an image processing system, consisting of a charge-coupled-device image sensor, an image memory board, a personal computer, and a phase-contrast microscope. Then added to a cell suspension, monoclonal antibody specific to the fetal thymus antigen-1 of the mouse leukemia GRSL cell produced cytolysis of only GRSL cells. This cytolysis decreased the brightness of the cells observed by phase-contrast microscopy. The remaining brightness was subtracted from that of the phase-contrast image of the cells before cytolysis, which had been converted to a digital signal and stored in computer memory. Measurement time is 2 s. The time course for complete GRSL cytolysis, as measured with this system, is 12 min; overall measurement time, including reaction time, is approximately 15 min. GRSL cells in a suspension of mixed cells were determined specifically by the system.
Lactate dehydrogenase isoenzyme 1 as determined by inhibition with 1,6-hexanediol and by two other methods in patients with myocardial infarction or cardiac-bypass surgery.
Authors: Shamberger R J 
Published: January 2020

Abstract
In this assay for lactate dehydrogenase (EC 1.1.1.27) isoenzyme 1 (LD-1), 1,6-hexanediol is added to serum after total LD has been measured. After incubation for 5 min the total LD remaining is determined. Samples from patients who had a myocardial infarction or who had undergone bypass surgery were assayed simultaneously by the 1,6-hexanediol method, the Roche "Isomune LD," and by electrophoresis on agarose gel. For 101 analyses of sera from bypass patients, correlations were high for results by the inhibitor method and electrophoresis (r = 0.96), by Roche Isomune and the inhibitor method (r = 0.96), and by the Roche method and electrophoresis (r = 0.97). In general, values for total LD were quite comparable by the three methods, but results by the inhibitor method seemed slightly higher and showed greater variability (CV) than those by the electrophoretic method. The assay is simple--requiring one reagent addition and a short incubation--and inexpensive: LD-1 can currently be determined for less than 1 over the cost of determining total LD.
Interference by goat-derived anti-lymphocyte globulin in a double-antibody radioimmunoassay of digoxin.
Authors: Coon M J , England B G , Annesley T M , Giacherio D A 
Published: January 2020

Abstract
Therapy with anti-lymphocyte and anti-thymocyte globulins, two animal-derived preparations used as immunosuppressive agents, results in high concentrations of foreign immunoglobulin circulating in plasma. We describe a case that illustrates how the presence of these immunoglobulins can interfere with double-antibody radioimmunoassay procedures.
Cellular oncogenes and human carcinogenesis.
Authors: Der C J 
Published: January 2020

Abstract
Experimental studies over the past decade have identified 30 or so cellular genes as potential oncogenes. The genetic events that lead to cellular oncogene activation may result in the excessive or inappropriate expression of the gene, or the expression of an aberrant gene product. Although the involvement of these putative cellular oncogenes in human oncogenesis has not been proven, the accumulation of considerable experimental evidence strongly implicates some role of these genes in the malignant process. The inactivation of certain genetic loci (suppressor genes) may also contribute to tumor progression.
Serum alkaline phosphatase isoenzymes in hepatobiliary disorders resolved by use of immobilized pH gradients.
Authors: Sorroche P , Bianchi-Bosisio A , Sinha P K , Gelfi C , Righetti P G 
Published: January 2020

Abstract
This new method for fractionating alkaline phosphatase isoforms in hepatobiliary disorders is based on isoelectric focusing on a mixed-type polyacrylamide support containing an immobilized pH gradient with a superimposed carrier-ampholyte gradient. The high-Mr alkaline phosphatase forms typical of hepatobiliary disease (greater than 1 mega-dalton), which cannot migrate into the Immobiline gel, are disaggregated in zwitterionic detergents (the most effective being sulfobetaine 3-12)--20 g/L in the sample, 5 g/L in the gel--suggesting that they are still complexed with membrane fragments or that they tend to aggregate spontaneously in solution. These isoforms focus in the pI 5-6 range (while alkaline phosphatases in normal serum focus in the pI 4-5 interval) in immobilized pH gradients, but behave as strongly acidic components by agarose isoelectric focusing in the presence of carrier ampholytes, suggesting that they are strongly complexed with the latter. On treatment with neuraminidase, the low-pI isoforms in normal serum focus in the pI 5-6 range typical of the hepatobiliary isoforms, suggesting that the latter are poorly glycosylated. By a second-dimension run, in a porosity gradient, followed by activity staining, all alkaline phosphatase forms that have entered the Immobiline gel in the first dimension (normal forms and high-Mr species) exhibit the same Mr (ca. 140,000 Da), suggesting that no new chains are synthesized in hepatobiliary disorders.
Radioimmunoassay of atrial natriuretic polypeptide in heat-treated human plasma.
Authors: Iinuma K , Ikeda I , Ogihara T , Hara H , Shima J , Kurata K , Kumahara Y 
Published: January 2020

Abstract
In this simple, sensitive radioimmunoassay (RIA) of atrial natriuretic polypeptide (hANP) in human plasma, nonspecific interference is minimized by deproteinizing the plasma by heat treatment at 85 degrees C for 10 min. We directly measure alpha-hANP in the supernates by RIA, with use of antiserum that recognizes the N-terminal region of alpha-hANP. The minimal detectable value was 0.4 pg per tube. The intra-assay CV was 6.6% (n = 8). The mean concentration of hANP in plasma of 54 healthy volunteers was 41 (SD 29) ng/L. Concentrations of hANP in plasma increased after saline infusion and high salt intake for one week in patients with essential hypertension. High concentrations were also measured in patients with renal failure and congestive heart failure. This method, which requires no extraction or purification with column chromatography, is especially useful for simultaneous measurement of several samples.
Identification and quantification of a protein-bound ligand in uremic serum.
Authors: Takeda N , Niwa T , Tatematsu A , Suzuki M 
Published: January 2020

Abstract
A major protein-bound ligand in the serum of chronic hemodialysis patients was isolated from heat-deproteinized uremic serum by "high-performance" liquid chromatography (HPLC). The isolated compound was identified as 3-carboxy-4-methyl-5-propyl-2-furanpropionic acid by use of liquid secondary-ion mass spectrometry and gas chromatography-mass spectrometry. On HPLC, an authentic sample of this compound showed a retention time identical to that of the protein-bound ligand peak. The concentration of the furancarboxylic acid in serum, as estimated by HPLC, is markedly greater in chronic hemodialysis patients than in normal subjects.
Mathematical treatment of data for calculating activities of alpha-amylase isoenzymes.
Authors: Redondo F L 
Published: January 2020

Abstract
Methods for determining alpha-amylase isoenzymes by selective inhibition with a wheat-germ protein are practical and easy, and give accurate, precise results. The incomplete specificity of the inhibitory action is not a major drawback but does necessitate mathematical treatment of the data (i.e., enzymic activities measured before and after preincubation with the inhibitor) to ascertain the amount of the different isoamylases. Such an algorithm is quite simple and straightforward, because the isoenzymes can be calculated either arithmetically or geometrically, by using a linear standard curve, empirically obtained, that relates the fraction of activity remaining after inhibition (R/T) to the pancreatic isoenzyme fraction or to the percentage of total alpha-amylase (P/T or 100 X P/T). An alternative method, plotting R/T against the ratio of pancreatic to salivary isoenzyme (P/S), is inconvenient, necessarily yields a nonlinear curve, needlessly complicates the calculations, and has been a persistent source of confusion in many articles dealing with the differentiation of isoamylases.
Nonenzymatic glycation of immunoglobulins does not impair antigen-antibody binding.
Authors: Morin L G , Austin G E , Burkhalter A 
Published: January 2020

Abstract
We glycated immunoglobulins from commercial kits designed to measure human ferritin, thyrotropin, and transferrin, and compared the calibration curves for assays utilizing glycated antibodies with those of assays utilizing non-glycated antibodies. Glycation was verified by borate affinity chromatography and assay with thiobarbituric acid reagent. We found no evidence that antigen-antibody binding is impaired by nonenzymatic glycation of antibodies. Our results provide no evidence in support of the supposition that glycation may be a contributory factor in the decreased resistance of diabetics to infection.
Enzyme-linked immunosorbent assay for 17 alpha-hydroxyprogesterone in dried blood spotted on filter paper.
Authors: Maeda M , Arakawa H , Tsuji A , Yamagami Y , Isozaki A , Takahashi T , Haruki E 
Published: January 2020

Abstract
In this rapid, cost-effective, enzyme-linked immunosorbent assay for 17 alpha-hydroxyprogesterone (17-OHP) eluted from dried blood spotted on filter paper, second antibody is coated onto the microwell plate and horseradish peroxidase (EC 1.11.1.7) is the label enzyme. Antiserum to 17-OHP was prepared by using 4-(2-carboxymethylthio)-17-OHP-bovine serum albumin conjugate as immunogen. Enzyme conjugate was prepared from 4-(2-carboxymethylthio)-17-OHP and peroxidase. The blood spots are assayed in the microwells without extraction or centrifugation steps. The detection limit of the assay is 1 microgram/L, equivalent to 3.5 pg (10.6 fmol) per disc. Intra- and interassay CVs at two steroid concentrations (7.38 and 22.79 micrograms/L) ranged from 3.74 to 11.90% (n = 5), and 9.49 and 9.83% (n = 5), respectively. Results correlated well (r = 0.91) with those of a fluorescence enzyme immunoassay. The sensitivity, specificity, and precision of this method make it potentially useful in the mass screening of neonates for congenital adrenal hyperplasia.
Delta bilirubin: absorption spectra, molar absorptivity, and reactivity in the diazo reaction.
Authors: Doumas B T , Wu T W , Jendrzejczak B 
Published: January 2020

Abstract
Delta bilirubin (B delta), isolated from serum, has an absorption maximum near 440 nm and a molar absorptivity of 72,000 L mol-1cm-1 in either Tris HCl (0.1 mol/L, pH 8.5) or phosphate (0.13 mol/L, pH 7.4) buffer. This absorptivity exceeds by approximately 50% and 59%, respectively, that of unconjugated bilirubin in the same buffers. This finding suggests that substantial errors can be incurred in direct spectrophotometry of bilirubins in serum. In the total diazo (TBIL) assay (Clin Chem 1985;31:1779-89), the color yield from B delta increases by 10% as the final diazo concentration is increased from 0.27 to 0.81 mmol/L. In the direct (DBIL) assay, if done in HCl (50 mmol/L), B delta yields approximately 15% more color as the diazo concentration is increased from 0.51 to 1.53 mmol/L, whereas in acetate buffer (0.4 mol/L, pH 4.7) the corresponding color yield is 25% greater. However, the absolute color yield for the reaction in HCl exceeds that in acetate buffer. In both the TBIL and the DBIL assay, B delta reacts slowly, nearly complete reaction requiring 10 min. Thus, B delta may be seriously underestimated in diazo (especially DBIL) methods in which short reaction times (20 s to 1 min) are used.
Improved assay for etoposide in plasma by radial-compression liquid chromatography with electrochemical detection.
Authors: el-Yazigi A , Martin C R 
Published: January 2020

Abstract
We describe a rapid, sensitive, and expedient radial-compression liquid-chromatographic method for routine quantification of etoposide (VP-16-213) in plasma of cancer patients undergoing chemotherapy with this agent. Teniposide was used as the internal standard. The mobile phase was a mixture of 10 mmol/L phosphate solution and methanol (50.7/49.3, by vol), adjusted to pH 3 with phosphoric acid. The flow rate was 2 mL/min. We used a 5-micron particle size C18 cartridge with a radial-compression separation system. The effluent was monitored with an electrochemical detector. Plasma samples are extracted with chloroform and the chloroform is evaporated. The residue, reconstituted in mobile phase, is injected onto the cartridge. Assay results were linearly related to concentration (r greater than 0.9944) over the range examined, 0.010-28.0 mg/L. The intra-run CV was less than 4.4%, and we encountered no interference from anticancer drugs or other compounds. We present data for plasma sampled at different intervals from two cancer patients being infused with etoposide.
Improved accuracy of cholinesterase phenotyping after participation in a proficiency survey.
Authors: Evans R T , Walker A , Bowness K M 
Published: January 2020

Abstract
We report results of an investigation into the proficiency of cholinesterase (EC 3.1.1.8) phenotying, assessed in 13 laboratories between 1983 and 1986. Thirty-two specimens of serum were distributed for analysis: two, each in duplicate, from the eight genotypes that can be recognized by differential enzyme inhibitor numbers. The accuracy of genotype ascription was markedly improved over that observed in an earlier study in which 12 of these laboratories took part, although the proportion of clinically significant errors did not change. Consequently, although participation in a proficiency testing program can lead to a considerable enhancement of performance, we still recommend the use of reference centers for detailed cholinesterase studies.
Isoelectric focusing of neuraminidase-treated alkaline phosphatase isoenzymes on agarose gel.
Authors: Root C F , Fine J S , Clayson K J 
Published: January 2020

Abstract
We attempted to separate bone and liver alkaline phosphatase (EC 3.1.3.1) isoenzymes in human serum by isoelectric focusing on agarose gel. We found that in a pH 3-10 gradient the liver and bone isoenzymes focused into so many bands over a narrow pH range such that the information could not be quantified. However, when the bone isoenzyme in serum was first desialylated at 37 degrees C for a minimum of 6 h, catalyzed by neuraminidase (EC 3.2.1.18) at pH 5.8-6.0, we could detect four distinct bands with pls of 6.7, 6.8, 6.9, and 7.0. Under the same conditions, the liver isoenzyme in human serum focused into one band at pH 7.0. The multiple banding we observed for the desialylated bone isoenzyme has not been previously reported. The method is suited as a qualitative technique for detecting the bone alkaline phosphatase isoenzyme in serum.
Generation 04 sodium slides and generation 04 reference fluid evaluated for use with the Ektachem 400 Analyzer.
Authors: Jack R M , Noble W 
Published: January 2020

Abstract
Evaluation of a new generation of sodium slides and reference fluid for use with the Kodak Ektachem 400 Analyzer demonstrated improved performance in generation 04 over the previous generation 03 slide for sodium determinations. A decrease in between-replicate imprecision and a correction of the "serum" assigned values of the calibrators used to calibrate the slide used with the reference fluid account for the improvement. When generation 04/Ektachem results (y) were compared with results obtained with a Beckman ion-selective electrode (x), linear regression statistics were: slope = 0.88, y-intercept = 15.4 mmol/L, and Syx = 2.1 mmol/L. The average fixed bias in comparison with the Beckman electrode decreased from +1.9 mmol/L with generation 03 to -0.6 mmol/L with generation 04 materials. Random error is indicated by a decrease in Syx from 2.8 mmol/L for generation 03 to 2.1 mmol/L for generation 04. Application of Deming's regression, a more accurate portrayal of the generation 04 sodium data set, produces a slope of 1.0 and a y-intercept of -0.6 mmol/L.
Preparation and stability of low-cost liquid quality-control serum stabilized with ethanediol.
Authors: Premachandra P , Wood P L , Hill P G , Browning D M , Olazabal D A 
Published: January 2020

Abstract
The use of quality-control serum to monitor laboratory performance is an essential part of any health laboratory. However, laboratories in many countries are disadvantaged because of the non-availability or high cost of commercial quality-control sera. Here we describe the stability of bovine serum stabilized with ethanediol, prepared at low cost by simple techniques that are available in most laboratories.
Initial assessment of tumor-associated antigen CA-125 in patients with ovarian, cervical, and testicular tumors.
Authors: Buamah P K , Cornell C , Skillen A W , Cantwell B M , Harris A L 
Published: January 2020

Abstract
Serum CA-125, a glycoprotein antigen, has been measured in serum of patients with ovarian cancer, cervical cancer, or nonseminomatous germ-cell tumor of testis. Increased concentrations were found in 21 of 27 patients with epithelial ovarian cancer and two of three patients with ovarian teratoma. Changes in CA-125 concentrations in serum during chemotherapy mirrored the progress of the disease as assessed by clinical and radiological evidence. Although CA-125 provides no real asset for diagnosis, it should have value as a marker for monitoring response to chemotherapy.
Effect of albumin and lamellar bodies on fluorescence polarization of amniotic fluid.
Authors: Ivie W M , Swanson J R 
Published: January 2020

Abstract
Using a probe and procedure developed for the Abbott TDx analyzer, we investigated the influence of albumin on fluorescence polarization of amniotic fluid. Polarization readings increased when albumin was added to either "mature" or "immature" amniotic fluids. Albumin added to a fraction rich in lamellar bodies (10,000 X g pellet) greatly increased polarization readings, but albumin added to the lamellar-body-free fraction resulted in only small increases. Adding increasing amounts of the lamellar-body-rich fraction from mature and immature pools to a constant amount of albumin decreased the polarization readings. We saw no correlation between amniotic fluid polarization and albumin concentration but found a significant correlation between polarization values and either total extractable phospholipids (r = 0.725, P less than 0.001) or the ratio albumin/total extractable phospholipids (r = 0.784, P less than 0.001). The concentration of albumin in amniotic fluid was variable and correlated poorly with gestational age.
Absorbance errors from using pieced-together rotors in the Roche Cobas-Bio centrifugal analyzer.
Authors: Miller W G , Armitage E K 
Published: January 2020

Abstract
Two Cobas-Bio analyzers were found to have significantly increased imprecision, owing to absorbance errors, when we used rotors pieced together from segments of four to 10 cuvets. The difference in CV between whole/unbroken and four-cuvet or 10-cuvet segment rotors was significant by Student's unpaired t-test (P = 0.038 and less than 0.0001, respectively) and by the Mann-Whitney U test (P less than 0.0001 for either). Pieced-together rotors were found to have plastic fragments in some cuvets, both adjacent to the break points and in other positions within the segment. There was no significant difference in delta A between adjacent cuvets at break positions or in between break positions by unpaired t-test (P = 0.214) or by the Mann-Whitney U test (P = 0.235). There was a significant difference by either test (P less than 0.0001) for the delta A between adjacent cuvets in broken rotors and those in whole/unbroken rotors. We conclude that random errors in absorbance are observed both in cuvets adjacent to break positions and in cuvets removed from the break point when pieced-together rotors are used.
Cefoxitin interferes with the "Clini-Skreen" column method for urinary 17-hydroxycorticosteroids.
Authors: Kroll M H , Jackson A J , Elin R J 
Published: January 2020

Abstract
Cefoxitin interferes with determination of urinary 17-hydroxycorticosteroids. The apparent concentration of hormone is increased from three- to 10-fold in samples from patients receiving cefoxitin when the Amberlite XAD-2 "Clini-Skreen" column is used. To determine the mechanism of interference, we reacted aqueous solutions of cefoxitin, cortisol, cortisone, and 11-deoxycortisol with phenylhydrazine; recorded the adsorption spectra; and determined the molar absorptivities and the equilibrium and rate constants. Also, we recorded the absorption spectra of phenylhydrazine with eight other cepha antibiotics and benzylpenicillin. Cortisol, cortisone, 11-deoxycortisol, and cefoxitin react with phenylhydrazine and absorb light with superimposable spectra and absorption maxima of 410 nm. The other antibiotics react with phenylhydrazine but absorbance maxima of the products vary, none being at 410 nm. Cortisol, cortisone, and 11-deoxycortisol react with phenylhydrazine 35-fold faster, have equilibrium constants ninefold greater, and have molar absorptivities 1.6 times that of cefoxitin. Thus, cefoxitin interferes with determination of urinary 17-hydroxycorticosteroids by forming a chromophore with the same absorbance maximum and with a molar absorptivity similar to cortisol, but much more slowly.
Automated determination of angiotensin-converting enzyme in serum.
Authors: Peters R H , Golbach A J , van den Bergh F A 
Published: January 2020

Abstract
This is an adaptation of the Fujirebio "ACEcolor" kit for automated measurement of angiotensin-converting enzyme (EC 3.4.15.1) in serum with the Cobas Fara centrifugal analyzer. The linear range extends to an activity of 110 U/L. Results obtained by the present method and by the manual method were identical, and correlated closely (r = 0.983) with those by Cushman's modified method. The reference interval for 77 adult blood-bank donors was 9-25 U/L (mean 17, SD 4 U/L). Within-run and between-run CVs are 1.7 and 4.0%, respectively. The present method permits rapid, precise, and economical measurement of the enzyme and allows users of a Cobas Fara centrifugal analyzer to introduce a fully automated assay for angiotensin-converting enzyme into their clinical laboratory.