bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concentrations of atrial natriuretic peptide in plasma and urine of kidney disease patients
Authors: Marumo F , Sakamoto H , Ando K , Ishigami T , Ishigama T 
Published: January 2020

Abstract
Concentrations of human atrial natriuretic peptide-like immunoreactivity (hANP-LI) were measured by a highly sensitive and specific radioimmunoassay (Biochem Biophys Res Commun 1986;137:231-6) in normal subjects and in renal disease patients without accompanying congestive heart failure, hypertension, edema, diabetes, or pregnancy. We attempted to clarify whether the hANP-LI concentration in plasma was increased by loss of renal mass. We found no correlation between the hANP-LI concentration in plasma and creatinine clearance (Ccr, 4.6-122.3 mL/min) in patients with renal disease (n = 63, r = -0.196), nor between hANP-LI concentrations in plasma and urine (n = 97, r = -0.207). The fractional excretion of hANP (FEhANP) correlated significantly with Ccr (n = 63, r = 0.520, P less than 0.01) and with FENa (n = 35, r = -0.503, P less than 0.01). Increased FEhANP in patients with chronic renal failure may have resulted because of an increase in single-nephron glomerular filtration rate similar to the FENa increase in these patients. The present data indicate that decreased renal function itself does not increase the concentration of hANP-LI in plasma.
Assay of creatine kinase isoenzyme MB in serum with time-resolved immunofluorometry
Authors: Lianidou E S , Christopoulos T K , Diamandis E P 
Published: January 2020

Abstract
We describe the first time-resolved immunofluorometric assay for creatine kinase (EC 2.7.3.2) isoenzyme MB (CK-MB) in serum. The assay is based on the formation of the complex: solid-phase anti-CK-MB-CK-MB-biotinylated anti-CK-BB-streptavidin-BCPDA-Eu3+, where anti-CK-MB and anti-CK-BB are monoclonal antibodies against the CK isoenzymes MB and BB, respectively, and BCPDA is the europium chelator 4,7-bis(chlorosulfophenyl)-1,10-phenanthroline-2,9-dicarboxylic acid. The solid-phase complex is fluorescent and is measured on the dry solid-phase (microtiter well) in a specially designed time-resolved fluorometer that uses laser excitation. The assay requires 25 microL of serum and is not affected by the presence of either CK-MM (up to 5000 micrograms/L) or CK-BB (up to 1000 micrograms/L) in the sample. Precision and accuracy indices for the assay were satisfactory.
Increase in lactate dehydrogenase isoenzyme-1 in plasma in pediatric malignancy
Authors: Sacks S S , Mulligan G 
Published: January 2020

Abstract
We investigated 28 cases of pediatric malignancy in which total lactate dehydrogenase (LD, EC 1.1.1.27) activities were increased and isoenzyme LD-1 exceeded LD-2 (flipped pattern). Of these, 11 had a flipped pattern at presentation and 17 showed a flipped pattern during chemotherapy. Those with flipped patterns at presentation were four with germ-cell tumors, one with acute lymphocytic leukemia, and six with nephroblastomas (Wilms tumor). Four of five nephroblastoma homogenates contained predominantly LD-1; one revealed a structurally normal LD-1 with normal kinetics. We conclude that an increase in LD with a flipped pattern is common in nephroblastoma and, in addition, may develop in cancer patients treated with chemotherapy.
Common and rare genotypes of human apolipoprotein E determined by specific restriction profiles of polymerase chain reaction-amplified DNA
Authors: Richard P , Thomas G , de Zulueta M P , De Gennes J L , Thomas M , Cassaigne A , Béréziat G , Iron A 
Published: January 2020

Abstract
The three common isoforms of human apolipoprotein E (apo E) differ at positions 112 and 158 and are named E3, E4, and E2 according to phenotyping by isoelectric focusing (IEF). The polymerase chain reaction (PCR) method allows the detection of common and several rare allelic apo E variants not detected by IEF. We propose a genotyping procedure for apo E that characterizes a given allele on the basis of amplification of specific sequences of the gene followed by the action of restriction endonucleases. When the nucleotide change does not lead to a restriction site, PCR-directed mutagenesis creates the discriminant site, and the differentiation of the three common alleles and five rare variants is possible. We present here profiles of common alleles and of three rare alleles, Weisgraber [Cys112/Asp127/Cys158], Christchurch [Cys112/Ser136/Arg158], and a new rare variant [Cys112/Leu142/Cys158].
Analytical evaluation of Kone Microlyte determination of ionized magnesium
Authors: van Ingen H E , Huijgen H J , Kok W T , Sanders G T 
Published: January 2020

Abstract
We performed an analytical evaluation of a commercially available instrument for determining ionized magnesium through use of a neutral carrier, liquid-membrane-based ion-selective electrode. Reproducibility (CV 2-4%), linearity (0.30-2.50 mmol/L), lower limit of detection (0.30 mmol/L), and absence of interference from Ca2+ indicate adequate performance for measuring ionized magnesium in plasma or serum samples in the normal to high-concentration range. Sodium in excess of 150 mmol/L caused a negative bias, which can be explained by ionic strength-induced changes in activity coefficients. The use of heparin as an anticoagulant must be restricted to concentrations &lt; 15 units/mL because of the binding of magnesium to heparin. The mean +/- SD concentration of ionized magnesium and its fraction of total magnesium in 76 healthy volunteers were 0.56 +/- 0.05 mmol/L and 0.65 +/- 0.04, respectively.
Time-resolved immunofluorometric assay of total renin in plasma and follicular fluid
Authors: Matinlauri I , Eskola J U , Aalto M , Koskinen P , Irjala K 
Published: January 2020

Abstract
We developed a new time-resolved immunofluorometric assay (TR-IFMA) using two monoclonal antibodies for the total renin measurement in human plasma and follicular fluid. No conversion of prorenin to renin was needed because the assay detected both renin and prorenin. The detection limit of the assay was 10 ng/L and the linear range was 10-25,000 ng/L. Within-assay precision (CV) was 15-8% at renin concentrations of 50-12,200 ng/L. Between-assay precision was 19-3% at concentrations of 100-18,000 ng/L. Analytical recovery of added renin was 85-104% (n = 5) in plasma samples and 104-119% (n = 3) in follicular fluids. For plasma, the reference interval was 78-262 ng/L in men (n = 44) and 36-226 ng/L in women (n = 43).
Complex pattern of alternative splicing in the normal uroporphyrinogen decarboxylase gene: implications for diagnosis of familial porphyria cutanea tarda
Authors: McManus J F , Begley C G , Ratnaike S 
Published: January 2020

Abstract
We describe multiple alternative transcripts of uroporphyrinogen decarboxylase mRNA in normal individuals and patients with familial porphyria cutanea tarda. mRNA was reverse-transcribed, subjected to the polymerase chain reaction, and analyzed for nucleotide sequence. Seven different transcripts were characterized, and a cryptic splice acceptor site was identified in intron 1. In all mRNAs the exons abutted at previously defined exon boundaries. Characterization of the splice junctions in the genomic DNA showed that splice donor and acceptor sequences complied with the consensus sequences for these sites except for the splice acceptor sequences of exons 3 and 10. THese deviations were present in two normal individuals and one patient with familial porphyria cutanea tarda and were thus unable to explain the multiple aberrant uroporphyrinogen decarboxylase transcripts. We conclude that apparent deletions observed in transcripts derived from the uroporphyrinogen decarboxylase gene in patients with familial porphyria cutanea tarda should be interpreted with caution.
Indicators of Iron Status in Nonanemic Elderly Subjects: Influence of Sex and Age
Authors: Marie Bernadette , Cals Marie-Joséphe , De Jaeger Christophe , Lowenstein William , Durand Hervè , Ekindjian Ohvanesse G 
Published: January 2020

Abstract
Vol. 40:
p. 1780. In the Technical Brief by B. Marie, M.-J. Cals, C. De Jaeger, W. Lowenstein, H. Durand, and O. G. Ekindjian entitled "Indicators of iron status in nonanemic elderly subjects: influence of sex and age," 1994;40:1779-81, in the legend to Fig. 1, the concentration of ferritin should have been expressed in micrograms per liter (µg/L), not picograms per liter.
Association of pancreatic adenocarcinoma, mild lung disease, and delta F508 mutation in a cystic fibrosis patient
Authors: Tsongalis G J , Faber G , Dalldorf F G , Friedman K J , Silverman L M , Yankaskas J R 
Published: January 2020

Abstract
A case of adenocarcinoma of the pancreas and mild lung disease in a 39-year-old man homozygous for the delta F508 cystic fibrosis mutation is presented. Cystic fibrosis is the most common lethal genetic disease in Caucasians, and is most commonly associated with severe obstructive lung disease. To our knowledge, this is only the fifth case of adenocarcinoma of the pancreas in a CF patient to be reported and the first case for which molecular data are available. The rare incidence of this type of malignancy in the general population suggests a possible association of CF with this malignant disease.
Interference with clinical laboratory analyses
Authors: Kroll M H , Elin R J 
Published: January 2020

Abstract
Interference by endogenous and exogenous substances with assays for clinical analytes is a common problem in laboratory medicine. For this review, we defined interference as "the effect of a substance present in the sample that alters the correct value of the result, usually expressed as concentration or activity, for an analyte." There are four major endogenous compounds that consistently interfere with laboratory results: hemoglobin, bilirubin, lipids, and paraproteins. The major exogenous sources of interference are drugs prescribed for the patient; and there are several excellent compendia of the effect of drugs on clinical laboratory tests. We recommend determining whether the interference is dependent or independent of the analyte for the assay. Further, we propose an approach to the identification and resolution of an interference problem for the clinical laboratory and make recommendations to manufacturers.
Fully automated flow-injection system for quantifying 1,5-anhydro-D-glucitol in serum
Authors: Tanabe T , Umegae Y , Koyashiki Y , Kato Y , Fukahori K , Tajima S , Yabuuchi M 
Published: January 2020

Abstract
We have developed a flow-injection system with colorimetric detection to measure 1,5-anhydro-D-glucitol in serum. Serum samples are directly and serially injected into a clean-up column every 3.5 min to remove interferences before the enzymatic reaction. 1,5-Anhydro-D-glucitol, after being passed through the column, is oxidized by immobilized pyranose oxidase (EC 1.1.3.10), and the hydrogen peroxide produced reacts with the chromogen substrate in the presence of immobilized horseradish peroxidase (EC 1.11.1.7) to form Bindshedler's Green. The detection limit was 1.2 mumol/L (1.2 pmol). The correlation between results obtained with the present system (y) and gas chromatography-mass spectrometry (GC-MS) (x) in samples containing &lt; 30 mumol/L 1,5-anhydro-D-glucitol, including many samples from patients with diabetes mellitus, was y = 0.975x-0.111 mumol/L (r = 0.997), which was superior to that obtained between the enzymatic and GC-MS methods. Our system needs only to be set up; it runs without any manual pretreatment, assays 17 samples/h, and shows imprecision (CV) of &lt; 2%.
Measurement of human urinary prolactin as a noninvasive study tool
Authors: Keely E J , Faiman C 
Published: January 2020

Abstract
We used a time-resolved solid-phase fluoroimmunoassay with a sensitivity of 25 ng/L on 40-fold-concentrated urines to measure urine prolactin (PRL) excretion. The nature of the immunoreactive material was verified to be PRL by: (a) column chromatography showing a monomeric 23-kDa peak; (b) similarity between fluoroimmunoassay and bioassay (Nb2 lymphoma cell) results; and (c) Western blot identification. In 20 normal subjects [serum PRL 6.8 (3.8-14.0) micrograms/L, median (and range)], urine PRL excretion was 0.15 (0.07-0.23) ng/h and 0.24 (0.15-0.54) micrograms/mol of creatinine. Urine values in seven hyperprolactinemic patients were all greater than the upper limit of normal. The correlation between urinary excretion rate and serum values was highly significant (r = 0.979; P &lt; 0.001). These results indicate that a monomeric, immunologically reactive, biologically active form of PRL can be measured in urine at concentrations approximately 0.0005 that in serum. This urine PRL method may provide a practical tool for the repetitive, noninvasive study of PRL dynamics in field studies and in patients with reproductive disorders.
Pancreatic lipase assays with triglycerides as substrate: contribution of each sequential reaction to product formation
Authors: Lykidis A , Mougios V , Arzoglou P 
Published: January 2020

Abstract
Human pancreatic lipase assays are usually performed in the presence of either emulsified triglycerides or diglycerides within the limits of their solubility. Two reactions are catalyzed in the presence of triglycerides: hydrolysis of triglycerides to diglycerides, and diglycerides to monoglycerides. The contribution of each reaction to the final result was determined after extensive kinetic studies on the appearance and/(or) accumulation of intermediates and/(or) products. Acylated glycerides were analyzed after extraction from the reaction mixture, separation of lipid classes by thin-layer chromatography, and quantification by capillary gas chromatography. The results show that after 10 min of reaction in the presence of high concentrations of triolein, 75% of the released fatty acids arise from the first reaction. Relative merits and disadvantages of each substrate (triglyceride or diglyceride) are discussed in terms of practicability.
Laboratory support for transplantation
Authors: Yatscoff R W 
Published: January 2020

Abstract
The clinical laboratory plays a major role in support of transplantation. Depending on the spectrum and number of transplants performed, such programs can consume up to 35% of all laboratory testing. This testing can be transplantation-nonspecific or -specific. The former constitutes routine laboratory procedures in various areas of laboratory medicine that are common to other categories of patients. Transplantation-specific testing includes tissue typing, procedures for assessment of graft viability/rejection, and measurement of immunosuppressive drugs. Because of the development of new immunosuppressive drugs such as FK506, cyclosporin G, and rapamycin, an increased burden will be placed on laboratories to establish new therapeutic monitoring programs. Preliminary guidelines for monitoring these drugs, similar to those previously established for cyclosporin A, are proposed herein. With the use of an increasing spectrum of immunosuppressive drug combinations, and the possible use of xenotransplantation on the horizon, new demands will be placed on the laboratory for the support of transplant programs.
Advances in diagnosis, prevention, and management of hepatic allograft rejection
Authors: Wiesner R H 
Published: January 2020

Abstract
Despite recent improvements in immunosuppressive therapy, hepatic allograft rejection remains a major cause of morbidity and late graft loss in patients undergoing liver transplantation. Although some biochemical tests suggest hepatic allograft damage, the gold standard for defining rejection remains based on morphologic findings. Acute cellular rejection usually occurs within the first 3 weeks posttransplantation and the incidence varies between 40% and 70%. Ductopenic rejection occurs in 5-10% of patients undergoing initial liver transplantation and usually occurs between 6 weeks and 6 months after the procedure. Induction and maintenance of immunosuppression with triple-drug therapy (cyclosporine, prednisone, and azathioprine) and other combinations that include anti-lymphocyte preparations have led to an overall decrease in the incidence of both cellular and ductopenic rejection. In addition, the availability of FK506 as a rescue therapy has saved grafts in some patients experiencing chronic (ductopenic) rejection. Overall, the correlation between the degree of biochemical liver dysfunction and the presence and severity of histologic rejection remains poor. Histologic severity of rejection, however, suggests which patients will require more immunosuppressive therapy and which patients may need antilymphocyte therapy to control the rejection episode. Some rejection episodes remain resistant to all known therapy and eventually lead to graft loss. New immunosuppressive agents and regimens are needed to improve graft and patient survival, decrease the incidence of cellular and ductopenic rejection, minimize drug-related side effects and complications, and reduce the high cost of immunosuppressive therapy.
External quality assessment in primary health care by using fresh whole blood
Authors: Raabo E , Odum L 
Published: January 2020

Abstract
Desktop analyzers and single-test meters used in primary healthcare are mainly calibrated to measure whole blood. To minimize matrix effects of control materials in external quality assessment schemes, we stabilized fresh human EDTA-treated blood with sodium iodoacetate (1.8 mmol/L). The whole-blood based control material was useful for control of hemoglobin and glucose, the two most common analyses in primary care, even after storage at room temperature for at least 10 days and at 5 degrees C for 3 weeks. The material was also useful for control of cholesterol and creatinine analyses for samples stored as long as 3 days at ambient temperature.
Determination of a T/G polymorphism at nucleotide 3206 of the apolipoprotein C III gene by amplification refractory mutation system
Authors: Tsai M Y , Hanson N Q , Copeland K R , Beheshti I , Garg U 
Published: January 2020

Abstract
We used the amplification refractory mutation system (ARMS)--a polymerase-chain-reaction-based method--to determine the 3206 T-to-G polymorphism on exon 4 of the apolipoprotein (apo) C III gene. Apo C III is an inhibitor of the enzyme lipoprotein lipase (EC 3.1.1.34). Previous studies have demonstrated that a polymorphism at nucleotide 3175 on exon 4 of this gene is associated with hypertriglyceridemia. We studied 45 hypertriglyceridemic and 46 age-matched controls for the 3206 T-to-G polymorphism. The results showed a significant difference in the distribution of the genotypes with respect to this allele between the hypertriglyceridemic and control individuals. We also determined the presence of the SacI site at nucleotide 3175 in these same individuals and found no significant difference in SacI genotypes between the two groups. This study reaffirms the usefulness of ARMS as a simple, reliable method for detecting mutations and polymorphisms in clinical and epidemiological studies.
Detection of alpha-thalassemias by multiplex polymerase chain reaction
Authors: Bowie L J , Reddy P L , Nagabhushan M , Sevigny P 
Published: January 2020

Abstract
Although alpha-thalassemia is the most common genetic abnormality in the world, there is currently no routine laboratory method to definitively identify individuals who are affected. We describe a rapid and simple method that utilizes deletion-sensitive primers to amplify normal DNA sequences. Deletions involving the regions responsible for most of the alpha-thalassemia cases in the US prevent amplification with these primers. In tests with DNA isolated from small amounts (10 microL) of whole blood, the deletion-sensitive primers gave rise to the expected 248- and 375-bp (base pair) amplification products in normal individuals. These primers, along with primers designed to bind to a nonaffected control sequence from the hemoglobin beta chain, could be amplified simultaneously (multiplex polymerase chain reaction). This made it possible to detect heterozygotes for alpha-thalassemia-2 (one alpha locus deleted) by determining the ratios of the 248- and 375-bp amplification products to the product of the control sequence (268 bp). The method is rapid and simple and can be performed in a routine clinical laboratory.
Mass screening for cystic fibrosis heterozygotes: two assay systems compared
Authors: Gilfillan A , Axton R , Brock D J 
Published: January 2020

Abstract
Two different assay systems were used to detect mutant cystic fibrosis alleles in mouthwash samples from pregnant women attending antenatal clinics. In the first phase of the study, comprising 3110 consecutive samples, we compared the performance of an in-house system and a commercial amplification refractory mutation system (ARMS). Successful analyses were completed at first attempt in approximately 90% of samples, and the patient resampling rate was 1.1%. There were no false positives and only one detected false negative. In the second phase, comprising 3333 consecutive samples, only ARMS was used. Again, there were no false positives and the patient resampling rate dropped to 0.5%. On the basis of convenience and reduced operator time, we have elected to use ARMS for further screening for cystic fibrosis heterozygotes.
Solid-phase extraction combined with radioimmunoassay for measurement of zalcitabine (2',3'-dideoxycytidine) in plasma and serum
Authors: Roberts W L , Buckley T J , Rainey P M , Jatlow P I 
Published: January 2020

Abstract
Of the antiviral agents that are currently in clinical use in the US for therapy for human immunodeficiency virus infections, zalcitabine (ddC) is the most potent and is effective at the lowest plasma concentrations. The two reported procedures for measuring these low concentrations involve a chromatographic technique coupled with mass spectrometry. We have developed a procedure combining solid-phase extraction with a strong cation-exchange resin and commercially available RIA reagents for the quantification of ddC in plasma or serum. The method demonstrates good linearity, specificity, and precision, with overall CVs of &lt; 10% from 2-20 micrograms/L and 17% at 0.8 microgram/L (the lower limit of quantitation). No significant cross-reactivity with nucleoside analogs other than ddC analogs was noted. The major advantages of this assay are its efficiency and relative simplicity, which should facilitate its performance in many laboratories.
Estimating and minimizing effects of biologic sources of variation by relative range when measuring the mean of serum lipids and lipoproteins
Authors: Cooper G R , Smith S J , Myers G L , Sampson E J , Magid E 
Published: January 2020

Abstract
Biologic intraindividual variation (CVb) is a major source of inaccuracy in current lipid and lipoprotein measurements. Metaanalysis has been used to estimate the average CVb of serum total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC), and triglyceride (TG). These CVb values are larger than the National Cholesterol Education Program-accepted and -proposed analytic (CVa) goals. Measuring serial specimens reduces the error in determination of the mean concentration used in classification of the patient by cutoff points. We show (a) a convenient technique, based on the relative range, to qualitatively estimate and interpret biologic variation of TC, HDLC, LDLC, and TG, and (b) the number of serial specimens required to meet a total variation goal for measurements of mean lipid and lipoprotein values. A total variation goal has been selected that can be met by two serial specimens for a majority of individuals.