bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of six enzymes with the Kodak DTSC Module, a physician's office analyzer.
Authors: Ng R H , Altaffer M , O'Neill M , Mukadam H , Statland B E 
Published: January 2020

Abstract
We evaluated the performance of the Kodak DTSC Module for determination of alanine aminotransferase (ALT; EC 2.6.1.2), aspartate aminotransferase (2.5.1.2), alkaline phosphatase (3.1.3.1), creatine kinase (2.7.3.2), gamma-glutamyltransferase (2.3.2.2), and lactate dehydrogenase (1.1.1.27). The DTSC is a "special chemistry" accessory for the DT60 analyzer; the same multilayer film technology as that of the Ektachem 700 is used. The overall precision, assessed over a three-month period with two serum-based quality control materials, ranged from 2.2 to 8.0%. DTSC results for patients' specimens correlated well with those by the Technicon RA-1000 analyzer. The performance of the analyzer in linearity and interference studies was satisfactory for clinical use. The DTSC is simple to operate and has no technique-dependent step; it should be useful for the physician's office laboratory.
Importance of time interval between repeated measurements of total or high-density lipoprotein cholesterol when estimating an individual's baseline concentrations.
Authors: Rotterdam E P , Katan M B , Knuiman J T 
Published: January 2020

Abstract
We studied intra-individual variation in total and high-density lipoprotein (HDL) cholesterol in healthy volunteers (22 men and 19 women, ages 19 to 62 years) on controlled natural diets. The within-person coefficient of variation (CV) depended on the interval between blood samples, increasing from about 2% to 3% for measurements made 24 h apart to 4% to 5% for measurements made at four-day intervals or longer. We conclude that within-subject fluctuations in total and HDL cholesterol have a time constant of several days. Multiple measurements are generally needed to decide whether an asymptomatic subject exceeds a certain concentration of total or HDL cholesterol; we recommend that such measurements be made at least four days apart.
Glycogen storage disease type I: laboratory data and diagnosis.
Authors: Wakid N W , Bitar J G , Allam C K 
Published: January 2020

Abstract
A study of 20 cases of glycogen storage disease type I has shown differences from the classical picture. Hyperuricemia was observed in fewer than half of the cases. All patients had increased triglycerides in serum, but fewer than two thirds had increased concentrations of total cholesterol. There was a consistent increase of aminotransferases in serum. Many textbooks discuss hyperuricemia, lactic acidemia, and lipidemia in this disease without mentioning aminotransferases, and above-normal values for these enzymes ought to be given consideration, to avoid misdiagnosis. Glycogen storage disease type IB was detected by comparing glucose-6-phosphatase (EC 3.1.3.9) activity in frozen and unfrozen portions of the same liver biopsy. Latent activity, which appeared after freezing, increased the total activity to within the normal range (4.7-9.1 mumol/min per gram of tissue, wet weight) in type IB, but not in type IA.
Simple liquid-chromatographic measurement of vanillylmandelic acid and homovanillic acid in urine on filter paper for mass screening of neuroblastoma in infants.
Authors: Hanai J , Kawai T , Sato Y , Takasugi N , Nishi M , Takeda T 
Published: January 2020

Abstract
We describe a simple and rapid method for measuring catecholamine metabolites in urine collected on filter paper. By this method, "high-performance" liquid chromatography, urinary vanillylmandelic acid and homovanillic acid can be measured within 15 min after being eluted from filter paper treated with tartrate buffer. One hundred urine samples can be pretreated within 2 h and 100-120 samples analyzed at 18-min intervals overnight in two chromatographic systems. Moreover, urinary creatinine also can be measured rapidly because of the use of microtiter plates. We applied this method in a mass screening program for early detection of neuroblastoma in infants. Between April 1986 and March 1987, two patients with neuroblastoma were detected. In all, neuroblastoma has been detected in 17 of 88,887 infants so examined since April 1981.
Liquid chromatography with multichannel ultraviolet detection used for studying disorders of purine metabolism.
Authors: Kojima T , Nishina T , Kitamura M , Kamatani N , Nishioka K 
Published: January 2020

Abstract
We used a reversed-phase "high-performance" liquid-chromatographic system equipped with a multichannel ultraviolet spectrometric detector and a micro-computer for analyzing urine samples from patients with disorders of purine metabolism. This system recorded a series of absorption-spectrum data from a single chromatographic run and stored them for subsequent analysis. Because the retention times and ultraviolet absorption spectra of the eluates were recorded simultaneously, identification of peaks was easy and quite accurate for simultaneous quantification of orotidine, adenine, hypoxanthine, uric acid, xanthine, allopurinol (4-hydroxypyrazolo[3,4-d]pyrimidine), oxypurinol (4,6-dihydroxypyrazolo[3,4-d]pyrimidine), inosine, and 2,8-dihydroxyadenine--compounds extremely difficult or even impossible to quantify simultaneously with a conventional single-wavelength spectrometer. We used this method to investigate purine metabolites in urines from a patient with hereditary xanthinuria, three patients with 2,8-dihydroxyadenine urolithiasis, and a gouty subject taking allopurinol.
Diagnostic value of a modified assay of free triiodothyronine in serum.
Authors: Forshaw K M , van Heyningen C 
Published: January 2020

Abstract
The performance of a modified commercial (Diagnostic Products Corp.) assay for free triiodothyronine in serum was evaluated, and its diagnostic value was compared with two other methods for free triiodothyronine estimation in euthyroid subjects and in patients with thyroid dysfunction. No advantage was demonstrated for the modified assay as an index of thyroid status. In conditions involving thyroxin-binding globulin excess the modified assay produced misleading results more frequently than did the comparison methods.
Increased serum lactate dehydrogenase isoenzyme 1 and "flipped" LD-1/LD-2 ratio in myopathy associated with partial carnitine palmitoyltransferase deficiency.
Authors: Moses G C , Henderson A R 
Published: January 2020

Abstract
We describe a case of a limb-girdle myopathy presenting with myoglobinuria. A partial deficiency of muscle carnitine palmitoyltransferase (EC 2.3.1.21) may also have been present. All "muscle-type" serum enzymes were markedly increased (to between 30- and 400-fold their respective upper reference limits) and creatine kinase (EC 2.7.3.2) isoenzyme 2 (CK-MB) was increased 130-fold but was still less than 2% of the total creatine kinase activity. The isoenzyme pattern of lactate dehydrogenase (EC 1.1.1.27) in serum was "anodic," with isoenzyme 1 greater than isoenzyme 2--an unusual pattern for myopathies. The possible physiological basis for such a finding is discussed.
Separation and identification of alkaline phosphatase isoenzymes and isoforms in serum of healthy persons by isoelectric focusing.
Authors: Griffiths J , Black J 
Published: January 2020

Abstract
We have developed an isoelectric focusing procedure for resolving alkaline phosphatase (EC 3.1.3.1) isoenzymes and isoforms in serum. We use a thin-layer agarose gel film containing synthetic carrier ampholytes and a "separator" to flatten the pH gradient in the region of the isoenzyme and isoform isoelectric points. Sharp, highly resolved zones of enzyme activity are obtained by limiting diffusion; for this we rapidly couple the released product, 1-naphthol, to a diazonium salt, which forms a colored precipitate at the site of activity. We have resolved and identified 12 zones of alkaline phosphatase activity in the serum of ostensibly healthy persons within a wide age range. Theoretically, three basic isoenzymes are produced from independent gene loci: intestinal, placental, and nonspecific tissue alkaline phosphatase. The other zones of activity may be isoforms.
Bias and precision of cholesterol analysis by physician's office analyzers.
Authors: Koch T R , Mehta U , Lee H , Aziz K , Temel S , Donlon J A , Sherwin R 
Published: January 2020

Abstract
We studied the bias and precision of serum cholesterol analysis by physician's office analyzers. Total imprecision (CV range, %) for analysis of serum pools was: Abbott Vision 1.5%-1.9%; Ames Seralyzer 3.9%-4.5%; BMD Reflotron 2.3%-3.8%; Chrometrics Cholesterol Test System 2.3%-2.8%; Kodak DT-60 1.6%-2.2%. The Ames Seralyzer exhibited an excessive between-run component of variation. We collected, from 109 volunteers, samples of venous serum, heparin-treated whole blood, heparin-treated plasma, and fingerstick whole blood, and analyzed each type (where possible) with each system; serum was also analyzed in duplicate (by a proposed Reference Method) at the Centers for Disease Control. For assays with serum, the BMD Reflotron and Kodak DT-60 exhibited negative bias. All systems gave lower results for plasma and whole blood than for serum. All systems except the Kodak DT-60 were less precise for analysis of patients' sera than for analysis of serum pools; between-specimen variables may influence the results of these systems.
Double-label time-resolved immunofluorometry of lutropin and follitropin in serum.
Authors: Hemmilä I , Holttinen S , Pettersson K , Lövgren T 
Published: January 2020

Abstract
We describe a procedure for the simultaneous immunofluorometric assay of lutropin and follitropin in human serum, based on the use of monoclonal antibodies and of the fluorescent lanthanides Eu3+ and Tb3+. The alpha-chain-specific antibody was used as a common capture antibody on the surfaces of microtitration strips. The anti-beta-follitropin antibody was labeled with Tb3+, the anti-beta-lutropin antibody with Eu3+. After the immunoreactions had taken place, the bound fractions of the labels were dissociated in a fluorescence enhancement solution of pivaloyltrifluoroacetone, trioctylphosphine oxide, and Triton X-100 surfactant. In this solution both lanthanides can be measured successively with a time-resolved fluorometer. The detection limit of the assay is 0.1 int. unit/L for lutropin and 1 int. unit/L for follitropin. Results correlated well with those by commercial immunofluorometric assays and radioimmunoassays.
Enzyme immunoassay for simultaneous measurement of autoantibodies against thyroglobulin and thyroid microsome in serum.
Authors: Ng M L , Rajna A , Khalid B A 
Published: January 2020

Abstract
A combined enzyme immunoassay (micro-ELISA) technique was established for measuring autoantibodies against thyroglobulin and thyroid microsome, involving the immuno-dot blot technique. Thyroglobulin and thyroid microsome antigens (1 g/L each) prepared from normal thyroids were spotted separately onto nitrocellulose membrane filter discs. Results by this method and those by immunofluorescence correlated well. The percentages of confirmed positives were 30% and 48% and the negatives were 58% and 46% (n = 50) for thyroglobulin and microsome, respectively. Testing these samples by gelatin agglutination gave a high percentage of false positives (up to 20%, n = 128) and hemagglutination testing yielded a high percentage of false negatives (up to 20%, n = 45). The titer of autoantibodies by the micro-ELISA technique was greater than by agglutination. This technique is highly specific and sensitive.
Xanthine lithiasis, nephrocalcinosis, and renal failure in a leukemia patient treated with allopurinol.
Authors: Potter J L , Silvidi A A 
Published: January 2020

Abstract
An 11-year-old boy who presented in acute renal failure with significant increases of uric acid and phosphorus in his serum was discovered to have acute lymphoblastic leukemia. Five years later, he had a second and similar episode of acute renal failure, which was responsive to hemodialysis. After three months of daily therapy with allopurinol, a third and final episode of renal failure was unresponsive to peritoneal dialysis. Autopsy revealed an obstructive uropathy; focal nephrocalcinosis; and multiple, small, tan calculi in the calyces of both kidneys. Systemic cryptococcosis was also discovered. The stones, characterized by paper chromatography, electrophoresis, x-ray diffraction, and infrared spectroscopy, were 82% xanthine, 15% oxypurinol, and 3% hypoxanthine. We suggest that attention to the effects of accelerated tumor-cell lysis may protect renal function in patients with a large and drug-sensitive tumor cell load. Similarly, early detection of the fungal complications of leukemic therapy is an essential component of the treatment program.
Double IgA bands in serum from a patient with lymphoplasmacytoid leukemia with hairy-cell morphology.
Authors: Loo S Y , Bhagavan N V , Scottolini A G 
Published: January 2020

Abstract
We present a case of plasmacytoid lymphocytic leukemia with hairy-cell-like cytoplasmic projections and separate monomeric and polymeric IgA(lambda) serum bands confirmed by immunofixation. After a prolonged initial good response to chemotherapy, the patient had recurrent disease with increased plasmacytoid blastic feature and died. The relationship of this case to B-cell proliferative disorders is discussed.
Isolation and purification of placental type alkaline phosphatase from a seminoma.
Authors: Shameem G M , Qadri F 
Published: January 2020

Abstract
An alkaline phosphatase (EC 3.1.3.1) of the placental type was isolated from a seminoma type of human testicular cancer tissue and was purified to homogeneity by sulfate-mediated chromatography on a column of Cibacron Blue Sepharose 4B. The purified enzyme had a specific activity of 40.6 kU per gram of protein and was obtained in a yield of 37%. The purification procedure used was simple and economical, and may be used to purify alkaline phosphatase isoenzymes from other cancer tissues. This is the first report of the purification of the enzyme in seminoma. Inhibition studies suggest that this enzyme is a Nagao variant rather than the Regan type reported in several cancer tissues.
Quantification of 5 alpha- and 5 beta-androstanediols in urine by gas chromatography-mass spectrometry.
Authors: Muller L , Phillipou G 
Published: January 2020

Abstract
We measured concentrations of 5 alpha-androstane-3 alpha,17 beta-diol (Ad) and 5 beta-androstane-3 alpha,17 beta-diol (beta-Ad) in urine by specific capillary gas chromatography-mass spectrometry, with [16,16,17 alpha-2H3]-5 alpha-androstane-3 alpha,17 beta-diol as the internal standard. Comparison of the so-derived reference intervals for Ad and beta-Ad in men and women with those previously published indicates a significant positive bias for many of the previous assays in comparison with our procedure. Both Ad and beta-Ad have a pronounced diurnal rhythm, with maximum excretion in the interval 2300-0700 hours. Concentrations of Ad and beta-Ad were significantly correlated (r = 0.786, p less than 0.001), but the ratio of Ad to beta-Ad was not correlated to that for androsterone to etiocholanolone, the major 5 alpha and 5 beta metabolites of androgens in urine.
False-positive results for ketone with the drug mesna and other free-sulfhydryl compounds.
Authors: Csako G 
Published: January 2020

Abstract
All free-sulfhydryl compounds tested produced false-positive reactions in the Legal test for ketones. The color developed in the ketone pad of urine dipsticks [N-Multistix SG, Multistix 10 SG (Ames), and Chemstrip 9 (Boehringer-Mannheim)] was misinterpreted for ketone bodies, both by visual and automated reading. In contrast to the reaction with true ketones, a drop of glacial acetic acid added onto the ketone pad of dipsticks discharged the false-positive red color. A red-violet also developed instantly with free -SH compounds in the Acetest tablet assay (Ames), but quickly faded. In general, the presence of acidic groups such as -COOH and -SO3H in the structure appeared to increase the nitroprusside reactivity of free -SH compounds, whereas the presence of a -NH2 group appeared to decrease it. Currently, false-positive ketone reactions ascribable to a free -SH group are most likely to be seen for urine containing mesna. The false-positive test for ketones caused by free -SH compounds can be recognized and ruled out by proper procedures. On the other hand, this chromogenic reaction with free thiols might be used for monitoring urinary excretion of mesna.
Analytical chemistry at the Games of the XXIIIrd Olympiad in Los Angeles, 1984.
Authors: Catlin D H , Kammerer R C , Hatton C K , Sekera M H , Merdink J L 
Published: January 2020

Abstract
The equipment, methods, logistics, and results of doping-control analyses for the 1984 Los Angeles Olympic Games are discussed in this article. Within 15 days, 1510 different urine specimens underwent 9440 screening analyses by a combination of gas chromatography, gas chromatography-mass spectrometry, "high-performance" liquid chromatography, and radioimmunoassay. These tests covered more than 200 different drugs and metabolites, including psychomotor stimulants, sympathomimetic amines, central nervous system stimulants, narcotic analgesics, and anabolic steroids. The results are summarized by class of drug. Less than 2% of the samples were found to contain a banned drug.
Quality assurance in changing times: proposals for reform and research in the clinical laboratory field.
Authors: Kenney M L 
Published: January 2020

Abstract
The U.S. Department of Health and Human Services recently commissioned a comprehensive analysis of the effectiveness and appropriateness of federal clinical regulations. The analysis found that many federal regulations are technically obsolescent and many may be operationally unnecessary as a result of changing laboratory technology and changed federal reimbursement policies. Among changes recommended by the HHS-funded analysis are: the regulatory classification system based upon physical location of laboratories is no longer appropriate and should be replaced with a classification system reflecting laboratory functions; a single, uniform set of federal regulations should be developed that covers all civilian laboratories receiving federal reimbursement or operating in interstate commerce; a revised federal regulatory system should emphasize measures of performance such as personnel and inspection requirements; and clinical laboratory regulations should be based upon objective data to the maximum extent possible.
Alanine aminopeptidase in serum: automated optimized assay, and effects of age, sex, smoking, and alcohol consumption in a selected population.
Authors: Mueller P W , Phillips D L , Steinberg K K 
Published: January 2020

Abstract
In the diagnosis of chronic (as opposed to acute) liver diseases, combinations of indicators are needed to improve specificity. Alanine aminopeptidase (AAP; microsomal aminopeptidase, EC 3.4.11.2) activity in serum reportedly is a very sensitive indicator of intrahepatic cholestasis and biliary obstruction; it is also particularly useful in diagnosing chronic liver disease when combined with an indicator of hepatocyte damage such as aspartate aminotransferase or alanine aminotransferase. We optimized the assay of AAP in serum, automated the assay by using a centrifugal analyzer, then used this automated assay to determine activity in 202 individuals, ages one to 73 years. The preliminary results were analyzed in terms of the effects of age, sex, smoking, and alcohol consumption on AAP activity in serum. Striking sex-related differences were observed: AAP activity in males declined 2.5 times more rapidly with age than did that in females; indeed, activity in adult females remained essentially constant. Moreover, AAP values were higher in men who smoked than in those who did not, the difference being of borderline significance by analysis of covariance (p = 0.0865) but significant by partial correlations (p = 0.02). No similar differences were seen for women smokers and non-smokers. When the effects of other variables were held constant, alcohol consumption alone did not significantly correlate with AAP activity in men or women.
A two-step radioimmunoassay for free triiodothyronine in serum.
Authors: Rajan M G , Samuel A M 
Published: January 2020

Abstract
Using a high-affinity solid-phase-bound antibody (Ka = 1.2 X 10(11) L/mol), we have standardized a two-step radioimmunoassay for free triiodothyronine (FT3) in serum, based on immunoextraction. The method was validated by comparison with an equilibrium-dialysis procedure (r = 0.96) involving RIA of T3 in the dialysate standardized with the same antibody and by a commercial (Liso-Phase, International-CIS) method. The two-step RIA could detect as little as 0.2 pg per milliliter. The mean CVs within and between assays were 9% and 12%, respectively. FT3 values measured in 30 normal adults ranged from 1.77 to 4.77 ng/L. Comparison with ratios of total T3 to thyroxin-binding globulin showed good agreement in normal subjects, pregnant women, and hypothyroid and hyperthyroid patients.
A new enzymic determination of guanidinoacetic acid in urine.
Authors: Shirokane Y , Utsushikawa M , Nakajima M 
Published: January 2020

Abstract
We developed and evaluated a colorimetric method for enzymic determination of guanidinoacetic acid (GAA) in urine. Endogenous urinary urea was first eliminated by urease (EC 3.5.1.5), and the added urease was then removed from the sample by centrifugal ultrafiltration. GAA in the ultrafiltrate was subsequently hydrolyzed by guanidinoacetate amidinohydrolase (EC 3.5.3.2) to glycine and urea. The latter substance produced an orange chromogen reacting with o-phthalaldehyde and N-(1-naphthyl)-N'-diethylethylenediamine, the absorbance of which at 465 nm was linearly related to concentrations as high as 200 mg/L for standard solutions of GAA. Analytical recovery of GAA added to urine ranged from 94 to 112% (mean 101%) and the within-run and between-run precision (CVs) of the method for the urinary GAA determination averaged 2.2 and 3.5%, respectively. Results correlated well (r = 0.983) between the present method and a high-performance liquid chromatographic method. The proposed method is accurate and simple. We saw a great decrease in urinary GAA of patients with suspected or proven renal insufficiency as compared with that of healthy volunteers.
A patent law primer for clinical chemists and other scientists.
Authors: Blecher M 
Published: January 2020

Abstract
Patenting and commercialization by academic scientists, despite potential drawbacks, are on balance highly desirable if technology is to be transferred from the laboratory to the public use, and if the scientist and his institution are to be encouraged to participate in this transfer. If that premise is accepted, there is much that academic institutions can do to foster utilization of their biotechnological discoveries. Such institutions should have a patent policy that is known to all and that includes a professional patent administrator and clear administrative procedures for carrying out such policy. Scientists should be trained to recognize and protect their inventions and to appropriately disclose their inventions to their patent officers. Ideally, scientists should know the rudiments of the patent statutes of their own country and should be aware of what constitutes trade secrets. Scientists should be given guidance in working with patent attorneys in the preparation and prosecution of patent applications. Finally, given human nature, institutions should see to it that their scientists are provided with a suitable environment in which to invent, and appropriate incentives to do so.