bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of monoclonal antibodies to detect human placental alkaline phosphatase.
Authors: De Groote G , De Waele P , Van de Voorde A , De Broe M , Fiers W 
Published: January 2020

Abstract
Convenient, sensitive, and specific solid-phase immunoassays involving monoclonal antibody are described for the determination of human placental alkaline phosphatase (hPLAP). An endogenous enzyme immunoassay combined the specificity of the immunological and the enzymatic reactions. Alternatively, a solid-phase "sandwich" radioimmunoassay involving immobilized polyclonal rabbit anti-hPLAP in combination with iodinated monoclonal antibody provided some additional advantages. Both tests can be used to detect hPLAP from various sources, e.g., in human sera during pregnancy or as a tumor marker. The radioimmunoassay detected an increase in hPLAP at nine weeks of gestation. We discuss the use of monoclonal antibodies for the differentiation of different alkaline phosphatase isoenzyme types by electrophoresis on starch gel.
Immunonephelometric determination of apolipoprotein A-1 in hyperlipoproteinemic serum.
Authors: Heuck C C , Erbe I , Flint-Hansen P 
Published: January 2020

Abstract
The intensity of scattered light varies with the size of the scattering particles. Studying the quantitative immunonephelometric determination of apolipoprotein A-1 (apo A-1), we observed that the different particle sizes of lipoproteins must be taken into account in immunonephelometry if apo A-1 is a constituent of the lipoprotein particles. Because interaction between large lipoproteins and immunocomplexes of high-density lipoproteins increases light scattering nonspecifically, false estimations may be obtained in serum with excessive hyperlipoproteinemia. Furthermore, the accessibility of antigenic sites of apo A-1 in intact high-density lipoproteins is limited. Immunonephelometry of apo A-1 in serum necessitates therefore the elimination of various interferents, which we have achieved by a single one-step extraction of lipids in a two-phase liquid system. With n-hexanol/polyfluoro-polychloro-polyethylene, about 90% of the serum lipids are extracted and only apolipoprotein B is precipitated at the interphase. This pretreatment eliminates the interferences caused by excessive hypertriglyceridemia and therefore greatly facilitates the endpoint immunonephelometry of apo A-1 in normal and pathological serum samples.
Assay of cerebrospinal fluid protein: a rate biuret method evaluated.
Authors: Finley P R , Williams R J 
Published: January 2020

Abstract
We evaluated a rate colorimetric method (Beckman) for measuring total protein in cerebrospinal fluid. The automated instrument we used was Beckman's ASTRA TM. A 100-microL sample of spinal fluid is introduced into the biuret reagent in the reaction cell and the increase in absorbance at 545 nm is monitored for 20.5 s. Solid-state circuits determine the rate of alkaline biuret-protein chelate formation, which is directly proportional to the total protein concentration in the sample. The linear range of measurement is 120 to 7500 mg/L. Day-to-day precision (CV) over the range of 150 to 1200 mg/L ranged from 15.2 to 2.3%. The method was unaffected by radical alteration of the albumin/globulin ratio, but there is a positive interference in the presence of hemoglobin, a suppression in the presence of bilirubin, and no effect by xanthochromia. The method is precise, accurate, rapid, and convenient. The method was compared with the trichloroacetic acid method as performed on the Du Pont aca III, giving a correlation coefficient (r2) of 0.9693. The method is precise, accurate, rapid, and convenient.
Column enzyme immunoassay for secretory immunoglobulin A in serum.
Authors: Yamamoto R , Kimura S , Hattori S , Ishiguro Y , Kato K 
Published: January 2020

Abstract
This enzyme immunoassay for specific measurement of secretory immunoglobulin A concentrations in human serum involves use of a small chromatographic column as a solid-phase. Serum samples are incubated for 2 h with beta-D-galactosidase-labeled antibody to secretory component, then passed through a 0.1-mL Sepharose 4B column containing antibodies to human immunoglobulin A. After the column is washed to remove the unbound label, the buffer in the column is replaced by a solution of o-nitrophenyl-beta-D-galactoside (a beta-D-galactosidase substrate) and incubated at 25 degrees C overnight. The enzyme reaction is stopped by washing the column with sodium carbonate solution, and the absorbance of the eluate is measured at 420 nm. The concentration of secretory immunoglobulin A can be determined with a minimum detectable sensitivity of 3 mg/L, without interference from free immunoglobulin A and secretory component in the same samples.
Clinical and laboratory evaluation of a commercial kit for measurement of serum free thyroxin ("Amerlex Free T4").
Authors: Nasralla M , Hassan M , Al-Ansari A A , Kutob M , Al-Abdul Razak A , Al-Awqati M A 
Published: January 2020

Abstract
Different indexes of thyroid function were determined in conjunction with values obtained with a new commercial radioimmunoassay kit for serum free thyroxin, in 49 apparently healthy subjects, 87 pregnant women, and 142 outpatients attending the thyroid clinic. The results indicate a diagnostic success rate of 88% when free thyroxin was measured instead of estimating the so-called free thyroxin index. Furthermore, in three cases of papillary carcinoma the concentration of free thyroxin was increased, although all the other laboratory tests indicated a euthyroid state. Technically, the method is simple, rapid, and precise, and it would be of most value in the small hospital laboratory lacking the facilities of a comprehensive thyroid-function test service.
Remazol Brilliant Blue as a pre-stain for the immediate visualization of human serum proteins on polyacrylamide gel disc electrophoresis.
Authors: Saoji A M , Jad C Y , Kelkar S S 
Published: January 2020

Abstract
We describe the pre-staining of proteins in normal human serum with Remazol Brilliant Blue before separation by disc electrophoresis. Critical to reproducibility are: dye concentration of 0.16 mol/L in a Tris-glycine buffer (pH 8.3), use of equal volumes of serum and dye solution, a tagging period of 2 h at room temperature, and electrophoresis of 0.1 mL of the mixture at 2.5 mA/gel for about 2 h. Advantages include speed, quality of resolution, and low background. This method was compared with Amido Black post-electrophoresis staining in 35 sera. Of these, 16 showed identical results with respect to the number of bands. In the other 19, Amido Black showed more bands in the post-transferrin region and, sometimes, in the post-albumin region. The pre-stained gels showed slower electrophoretic mobilities of the components. Protein bands eluted from pre-stained gels retained immunological reactivity.
Heterozygote detection in congenital adrenal hyperplasia.
Authors: Handelsman D J , Howe C J , Conway A J , Turtle J R 
Published: January 2020

Abstract
Detection of heterozygote carriers for congenital adrenal hyperplasia by use of a modified tetracosactide (a synthetic corticotropin) stimulation test with prior overnight dexamethasone suppression proved to have a diagnostic accuracy of 95%. Discrimination of heterozygotes from normals was best when we used a criterion based on the ratios of 17 alpha-hydroxyprogesterone to cortisol at baseline and at 30 min after intravenous administration of 250 micrograms of tetracosactide.
A challenge of several concepts of free thyroxin index for assessing thyroid status in patients with altered thyroid-binding protein capacity.
Authors: Wilke T J 
Published: January 2020

Abstract
I compared values for the free thyroxin index derived from data obtained by four triiodothyronine-uptake kits for 93 euthyroid subjects with normal or altered thyroxin-binding globulin binding capacity. In addition, I devised a mathematical model of an "ideal" free thyroxin index. Only one uptake kit satisfactorily normalized values for the free thyroxin index in the increased thyroglobulin groups, as compared with the control. The other three demonstrated contrasting patterns of free thyroxin index variation as compared with normal, when thyroglobulin concentrations were increased. By all four uptake tests, values for the free thyroxin index in thyroglobulin-deficient patients were significantly lower than normal. Values derived from one uptake kit behaved similarly to those of the "ideal" model. The failure of the free thyroxin index to compensate for increases in thyroglobulin concentration is therefore a function of specific uptake methods rather than a characteristic of free thyroxin index per se. However, the free thyroxin index is not a true reflection of thyroid status in patients with thyroglobulin deficiency. The model suggests that a curvilinear relationship between triiodothyronine uptake and the concentration of thyroxin-binding globulin can result in a free thyroxin index that corrects for increases in thyroglobulin binding capacity.
Free thyroid hormone index, thyroid hormone/thyroxin-binding globulin ratio, triiodothyronine uptake, and thyroxin-binding globulin compared for diagnostic value regarding thyroid function.
Authors: Wilke T J 
Published: January 2020

Abstract
The thyroid hormone/thyroxin-binding globulin (TBG) ratio and the free thyroid hormone index (FTI) were compared in 372 subjects classified according to age, sex, and biochemical and clinical findings. Age-related variations in thyroid function tests were investigated, as was the relationship between triiodothyronine uptake and TBG. Men, but not women, showed significant age-dependent changes in concentrations of thyroid hormones. FTI was as good as the thyroid hormone/TBG ratio in hyperthyroidism and was a better index of thyroid status in pregnancy, TBG deficiency, and hypothyroidism. In addition, the triiodothyronine uptake correlated extremely well with TBG (r = -0.95, p less than 0.001) and was very efficient in detecting decreased and significantly increased concentrations of TBG. I conclude that FTI is a better discriminator of functional status of the thyroid over a wider range of TBG values than is the thyroid hormone/TBG ratio. Further, the triiodothyronine uptake test produced diagnostic information equivalent to that of TBG estimation and thus should not be replaced in routine use.
Estrone sulfate concentrations in plasma of normal individuals, postmenopausal women with breast cancer, and men with cirrhosis.
Authors: Rémy-Martin A , Prost O , Nicollier M , Burnod J , Adessi G L 
Published: January 2020

Abstract
Estrone sulfate is quantitatively the most important estrogen in plasma. A method for its determination in human plasma is described, and the precision, accuracy, sensitivity, and specificity are defined. Free steroids were extracted from plasma with diethyl ether and steroid sulfates were isolated with use of Vlitos' reagent (methylene blue in dilute H2SO4/Na2SO4 solution). After enzymic hydrolysis, estrone was isolated by chromatography on Celite and measured by radioimmunoassay. The mean concentrations (nmol/L +/- 1 SD) of estrone sulfate were 2.51 +/- 0.90 for plasma from 13 women in follicular phase, 5.33 +/- 1.55 for 17 women in luteal phase, 0.89 +/- 0.60 for 44 postmenopausal women, and 0.96 +/- 0.43 for 24 postmenopausal women with breast cancer. Results for postmenopausal women with or without breast cancer did not differ significantly. For 13 normal men, estrone sulfate concentrations were 2.62 +/- 0.79 nmol/L, and for a group of 19 cirrhotic men the mean value was 1.43 +/- 0.95 nmol/L, significantly lower than normal.
Characterization and elimination of a factor in serum that interferes with turbidimetry and nephelometry of lipase.
Authors: Kannisto H , Lalla M , Lukkari E 
Published: January 2020

Abstract
We studied a serum component ("pseudolipase") that interferes with both turbidimetric and nephelometric lipase measurements. Pseudolipase activity in serum was found in the presence of rheumatoid factor and in other disorders of active immune processes. The incidence of this interferent in sera seems to be greater than reported previously. We describe a method for eliminating its effect without affecting pancreatic lipase activity, by precipitating some of the proteins, including IgM, with polyethylene glycol.
Clinical acceptance of a multi-test reference region for biochemical-panel results.
Authors: Durbridge T C 
Published: January 2020

Abstract
Results of a panel of six biochemical tests on a patient's specimen were mathematically combined into a "six-test signal strength" (STSS) value. This value indicated the overall extent of change from physiological results, and it was calculated in a way that ensured that a STSS value less than or equal to 1 occurred in 95% of apparently healthy people. STSS was reported with the test results for hospital inpatients during a four-month trial period. Doctors requested a repeat of the panel less often when a low STSS was reported, even if some test results were outside their separate reference intervals. Clinicians expressed differing opinions about its usefulness, some finding that a high STSS value had saved them from overlooking abnormal results, others not finding the value to be any practical advantage. Using a multi-test normal region resolves a statistical dilemma, while compounding the problem of knowing what results really mean.
Protocol for the study of drug interferences in laboratory tests: cefotaxime interference in 24 clinical tests.
Authors: Baer D M , Jones R N , Mullooly J P , Horner W 
Published: January 2020

Abstract
We developed a protocol to study interference by cefotaxime and one of its major metabolites with 24 common chemical tests. Serum pools simulating specimens from healthy adults of both sexes, pregnant women, patients with liver disease, cardiac disease, or renal disease, and patients receiving gentamicin and tobramycin were supplemented with high and low concentrations of cefotaxime and desacetylcefotaxime. Using a discrete analyzer (the American Monitor Parallel), we tested 12 replicate samples from each condition for 24 analytes. Although statistically significant changes were found in many tests, 85% of the differences were less than 15% of the control value and more than half were less than 5%. The apparent concentration of creatinine was not significantly changed. Test results for phosphorus were increased in patients who were receiving gentamicin and tobramycin. No other changes were considered clinically significant.
Response curves for radioimmunoassay.
Authors: Finney D J 
Published: January 2020

Abstract
In quantitative estimates from radioimmunoassay, one of four types of response curves is usually used: a freehand curve, a spline function, an equation based upon mass-action considerations, or a logistic equation. This paper comments briefly on the subjectivity and labor of the first and on the overparametrization of the second. It is chiefly concerned to compare the single binding-site equation with a simple or modified logistic. Whatever the theoretical merits of the binding-site approach (these are not under discussion), estimation of parameters is difficult. The paper shows that under many but not all circumstances a four- or five-parameter logistic will fit data at least as well over a wide range of doses. This is particularly so when both the binding-site concentration and the equilibrium constant are small.
Semi-automated continuous-flow enzyme immunoassay for antiepileptic drugs in serum.
Authors: Hayashi S , Kurooka S , Arisue K , Kohda K , Hayashi C 
Published: January 2020

Abstract
We have developed a semi-automated method for measuring five kinds of antiepileptic drugs in serum by successfully adapting commercial competitive-binding enzyme immunoassay kits (MARKIT; Dainippon) for use with a continuous-flow analyzer (Technicon AutoAnalyzer II equipped with a dialyzer). The free enzyme-labeled drug is automatically separated by a microfilter from the competitive immunoreaction mixture between labeled and unlabeled drug for anti-drug immunoglobulin coupled to bacterial cell walls. The concentrations of the antiepileptic drugs in serum samples can be determined by automated measurement of enzyme activity of the enzyme-labeled drugs. Results of the semi-automated method correlated well with those obtained by manual enzyme immunoassay, gas-liquid chromatography, and "high-pressure" liquid chromatography. The correlation coefficients were all greater than 0.95, showing the practicality of this method for therapeutic monitoring of antiepileptic drugs.
Determination of bethanidine in plasma by liquid-chromatography with a microbore reversed-phase column.
Authors: Shipe J R , Arlinghaus A F , Savory J , Wills M R , DiMarco J P 
Published: January 2020

Abstract
In this novel method for quantifying bethanidine in plasma, after a multi-step extraction of bethanidine and internal standard from 2.0 mL of plasma, the drugs are separated on a "microbore" C18 reversed-phase column and quantified by their ultraviolet absorbance at 210 nm. The isocratic chromatographic separation takes about 15 min with use of an ion-pairing regent in the mobile phase (acetate buffer/acetonitrile, 9/1 by vol) and a flow rate of 0.25 mL/min. Sensitivity is increased relative to conventional columns, and solvent consumption is reduced by 90%. The standard curve is linear to at least 5 mg/L, and the detection limit is 0.02 mg/L. The within-run precision of the method is excellent (CV 4%) at a midrange concentration of 1.25 mg/L.
Polarization fluoroimmunoassay of 11-deoxycortisol in serum and saliva.
Authors: Al-Ansari A A , Massoud M , Perry L A , Smith D S 
Published: January 2020

Abstract
We developed polarization fluoroimmunoassays for 11-deoxycortisol in serum and saliva. To avoid interfering factors, the steroid was initially extracted from the biological fluids with dichloromethane. Assays could then be completed without any further separation procedures or need to correct for blank signals. The serum assay was suitable for following the response to the metyrapone test and results correlated acceptably with those by an established, specific, direct 125I-radioimmunoassay. The method is not sufficiently sensitive to detect 11-deoxycortisol in normal saliva, but greatly increased concentrations were found in post-metyrapone saliva and results agreed well with those by the radioimmunoassay as modified for salivary assay. Salivary 11-deoxycortisol assay would provide a convenient means of monitoring results of the metyrapone test.
Solid-state extraction of cortisol from plasma or serum for liquid chromatography.
Authors: Hofreiter B T , Mizera A C , Allen J P , Masi A M , Hicok W C 
Published: January 2020

Abstract
Solid-state extraction of plasma or serum offers significant advantages over traditional liquid-liquid methods in cortisol determinations by liquid chromatography (HPLC). Sample preparation is facilitated and HPLC column contamination is minimized. Extract yield from the solid-state columns is enhanced by sample pretreatment with methanol. Cortisol values by solid-state extraction/HPLC correlate well (r = 0.92) with those from a commercial radioimmunoassay procedure.
Abnormal regulation of pyridoxal 5'-phosphate in Reye's syndrome.
Authors: Faraj B A , Camp V M , Caplan D B , Ahmann P A , Kutner M 
Published: January 2020

Abstract
Seeking to determine the effect of liver disease associated with Reye's syndrome on the regulation of plasma pyridoxal 5'-phosphate, we measured this compound in plasma from 11 patients with biopsy-proven Reye's syndrome. Its concentrations in plasma are significantly higher [37.5 (SD 6.13) micrograms/L] at the onset of the disease than after treatment [8.50 (SD 2.9) micrograms/L] or in a group of hospitalized patients with no evidence of liver disease [8.4 (SD 1.5) micrograms/L]. The concentration of pyridoxal 5'-phosphate in plasma at the time the patients entered the hospital correlated significantly with their activities of serum alanine aminotransferase.
Profiles of urinary volatiles from metabolic disorders characterized by unusual odors.
Authors: Burke D G , Halpern B , Malegan D , McCairns E , Danks D , Schlesinger P , Wilken B 
Published: January 2020

Abstract
The profiles of urinary volatiles from patients with phenylketonuria, maple syrup urine disease, isovaleric acidemia, or trimethylaminuria (fish-odor syndrome) were in each case vastly different from the normal urinary volatiles profile. In the maple syrup urine disease case, metabolites that occur distal to the block were found and a mechanism for their formation is suggested. A new major metabolite in isovaleric acidemia was also found. As well as providing a reliable diagnostic tool for diseases characterized by odors, the analysis of urinary volatiles may provide information to help our understanding of still unexplained aspects of the diseases.
Optimizing reference values for the measurement of alpha 1-antitrypsin in serum: comparison of three methods.
Authors: Gaidulis L , Muensch H A , Maslow W C , Borer W Z 
Published: January 2020

Abstract
We studied three methods (rate nephelometry, radial immunodiffusion, and trypsin-inhibitory capacity) for their ability to detect those individuals with a deficiency of alpha1-antitrypsin. The phenotype represented in 170 serum samples was determined by isoelectric focusing as the reference method. All three methods correctly identified Pi Z, Pi S, and Pi SZ phenotypes but varied in their ability to detect Pi MZ and Pi MS phenotypes. The rate-nephelometric method was the least sensitive in detecting Pi MZ and Pi MS variants because of the inappropriately low reference interval suggested by the manufacturer. We found that the three screening methods are comparable when the limiting values are properly selected. We suggest that the reference value for the rate-nephelometric method be increased from 0.85 g/L to 1.40 g/L to improve the sensitivity of the test.
Two macromolecular complexes between alkaline phosphatase and immunoglobulin A in a patient's serum.
Authors: Wenham P R , Chapman B , Smith A F 
Published: January 2020

Abstract
We report the presence of two separate macromolecular complexes between an immunoglobulin and alkaline phosphatase (EC 3.1.3.1) in the serum of a patient with cholestatic liver disease. The complexes were seen as slow-moving bands on electrophoresis on polyacrylamide gel (70 g/L). Estimates of relative molecular mass for the two bands were 785 000 and 490 000 by gel chromatography on Sephacryl S300, and 640 000 and 420 000 by gradient gel-electrophoresis. Inhibitor and heat-inactivation studies showed that the two bands had similar properties, resembling the liver isoenzyme but more heat stable. Immunological studies suggested that both bands consisted of a complex of liver alkaline phosphatase with kappa type immunoglobulin A.
Hepatic infarction: biochemical study of a case.
Authors: Hoag G N , Orr T P , Amies D R 
Published: January 2020

Abstract
Hepatic infarction was observed post mortem in a 27-year-old man who died of aortic dissection. Blood had been sampled at admission and 12 and 19 hours later. Values for aspartate aminotransferase and alanine aminotransferase in serum were markedly above normal, whereas those for alkaline phosphatase and gamma-glutamyltransferase were only marginally increased. A threefold-increased creatine kinase was ascribable solely to isoenzyme CK-3, suggesting muscle breakdown. Moreover, total lactate dehydrogenase activity was increased threefold, accounted for by a ninefold increase in LD-5 isoenzyme. Those enzyme activities in serum that evidently are associated with acute hepatocellular necrosis increase quickly in hepatic infarction, and CK isoenzyme assay is a useful adjunct if LD-5 increases are significant.