bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood alcohol testing in the clinical laboratory: problems and suggested remedies
Authors: Frajola W J 
Published: January 2020

Abstract
Laboratory directors or others responsible for blood alcohol testing are advised to reevaluate their procedures for alcohol tests. The demand for better traffic safety has resulted in a large increase in the number of arrests for drinking and driving violations and in a concomitant increase in the litigation of alcohol-related cases. My experience in the last 20 years indicates that many difficulties in the forensic aspects of these cases and many miscarriages of justice could have been reduced or even avoided if laboratories doing alcohol analyses had followed established guidelines. The most frequently encountered problems involve the physician-patient privilege ("the test was done for medical purposes only") and the fact that alcohol results were frequently reported as blood alcohol concentrations when they were, in fact, serum alcohol concentrations. Here I discuss these problems and suggest some solutions.
Liposome-based flow-injection immunoassay for determining theophylline in serum
Authors: Locascio-Brown L , Plant A L , Chesler R , Kroll M , Ruddel M , Durst R A 
Published: January 2020

Abstract
We developed a method for quantitatively determining theophylline in serum, using a heterogeneous immunoassay called flow-injection immunoanalysis. The reaction involves competition between serum theophylline and theophylline-labeled liposomes. Separation occurs on a solid-phase reactor column containing immobilized antibody to theophylline incorporated in a flow-injection system. Subsequent lysis of the bound liposomes provides sensitive detection of the analyte. Effective regeneration of the immobilized antibody activity allows the reactor to be reused for hundreds of sequential samples. Comparison of the results of the flow-injection immunoassay method with results obtained with a commercially available fluorescence polarization method showed an excellent correlation.
Clinical and laboratory studies of a new immunoradiometric assay of parathyroid hormone-related protein
Authors: Fraser W D , Robinson J , Lawton R , Durham B , Gallacher S J , Boyle I T , Beastall G H , Logue F C 
Published: January 2020

Abstract
Parathyroid hormone-related protein (PTHrP) was measured in plasma by a new immunoradiometric assay (IRMA) from Nichols Institute. The assay is specific for PTHrP and shows excellent parallelism when measuring keratinocyte fluid, samples with high PTHrP content, and PTHrP-supplemented plasma. A precision profile established the assay detection limit at 0.7 pmol/L. PTHrP was unstable in plasma, but the degradation rate was patient-specific. Because delay in separation resulted in loss of PTHrP immunoreactivity, samples were collected into tubes containing protease inhibitors (aprotinin, leupeptin, pepstatin, and EDTA) and separated within 30 min. Among normal subjects, 78% had PTHrP values greater than the detection limit; the reference range established was &lt; 0.7-2.6 pmol/L. Of patients with hypercalcemia associated with malignancy, 46% had PTHrP &gt; 2.6 pmol/L. PTHrP was increased in patients with breast (73%), genitourinary (64%), or lung (46%) malignancy but was rarely above normal in patients with hematological (29%) or gastrointestinal (33%) malignancy. PTHrP and nephrogenous cyclic adenosine monophosphate (NcAMP) were strongly correlated (r = 0.63, P &lt; 0.01) in 37 patients with PTHrP values greater than the detection limit, but 8 patients had PTHrP and parathyroid hormone [PTH(1-84)] values below the limit of detection with inappropriate or increased NcAMP. Five of these eight patients had small cell carcinoma of lung. These patients may have secreted a factor that is not detected by the IRMAs of PTHrP or PTH used in this study but that produces hypercalcemia by means of cAMP-mediated mechanisms.
Rapid enzymatic analysis for human immunodeficiency virus type 1 DNA in clinical specimens
Authors: Sevall J S , Prince H , Garratty G , O'Brien W A , Zack J A 
Published: January 2020

Abstract
A clinical procedure for rapid detection of human immunodeficiency virus type 1 (HIV-1) by DNA amplification is demonstrated. The rapid procedure reduces handling requirements and amplification time and eliminates use of radioactivity for the detection of the amplification product. Total leukocyte lysates are the amplification substrates. Two conserved regions in the HIV-1 genome are amplified by 45 cycles of a two-temperature thermal cycle and the amplification products are detected by ultraviolet light after electrophoresis on agarose gels. Twenty-four specimens clinically diagnosed by detection of antibody (IgG) to HIV-1 were confirmed by the rapid DNA amplification procedure. In a blind study, 56 samples positive for HIV-1 DNA were detected in 503 individuals by the current classical polymerase chain reaction method; the same 56 positive samples were also detected by the rapid amplification protocol. No false-positive or false-negative results were obtained. The turnaround time for analysis has been reduced to &lt; 24 h without compromising test results.
Automated enzymatic determination of sodium in serum
Authors: Quiles R , Fernández-Romero J M , Fernández E , Luque de Castro M D , Valcárcel M 
Published: January 2020

Abstract
An automated method based on the principles of flow-injection analysis is proposed for the enzymatic determination of sodium ion in serum. The method relies on the activation of beta-galactosidase by the analyte. The features of the proposed method include linear range between 1 and 1700 mumol/L, a sampling rate of 50 samples/h, a sample volume of 50 microL, and the absence of interferences from species usually present in serum. The results obtained were consistent with those provided by widely used methods such as those based on flame spectrometry and direct potentiometry with ion-selective electrodes.
High-molecular-mass alkaline phosphatase as a tumor marker for colorectal cancer: comparison of two test methods
Authors: Wei J S , Chung N C , Wei L L , Tzeng W F , Liu T Z , Wang J Y 
Published: January 2020

Abstract
We measured high-molecular-mass alkaline phosphatase (HiMwALP) in serum samples from patients with colorectal cancer by polyacrylamide gel electrophoresis (PAGE) and by column chromatography on diethylaminoethyl (DEAE)-cellulose. Determination of carcinoembryonic antigen (CEA) by an enzyme immunoassay, a frequently used cancer assessment method, was used for comparison. We studied patients with primary colorectal cancer (n = 72), using others with hemorrhoids (n = 38) for a comparison group. HiMwALP activities twice those of pooled normal sera were adopted as cutoff values. The diagnostic sensitivity of the PAGE method for 72 colorectal cancer patients was 63% vs 36% for the DEAE method and 50% for the CEA method. The diagnostic specificities of the PAGE, DEAE, and CEA methods were 89%, 79%, and 95%, respectively. Using both HiMwALP (PAGE method) and CEA for the detection of primary colorectal cancer increased the sensitivity to 72% but decreased specificity to 87%.
Equivalent discrimination among states of thyroid function by immunochemiluminimetric and immunoradiometric determination of thyrotropin
Authors: Roden M , Nowotny P , Hollenstein U , Schneider B , Vierhapper H , Waldhäusl W 
Published: January 2020

Abstract
New immunochemiluminometric assays (ICMA) of thyrotropin (TSH) have been reported to facilitate the diagnosis of hyperthyroidism. To compare the accuracy of ICMA-TSH with that of a conventional immunoradiometric assay (IRMA-TSH), we examined 115 consecutive patients of a thyroid outpatient clinic. On the basis of complete thyroid-function testing, including thyroliberin tests, the untreated patients (n = 89) were subclinically hyperthyroid (n = 21), subclinically hypothyroid (n = 13), or euthyroid (n = 55). The receiver-operating characteristic (ROC) curve, used for comparing the TSH values obtained by these two methods, was shifted to the left for the IRMA-TSH. The area under the curve was greater for IRMA-TSH than for ICMA-TSH (0.984 vs 0.869, respectively), which suggests equal or better clinical performance of IRMA-TSH vs ICMA-TSH in discriminating between hyperthyroidism and euthyroidism. Both assays displayed similar clinical sensitivity/specificity for evaluating thyroid function in hypothyroid and treated patients. We conclude that the ICMA-TSH tested is not more accurate than an IRMA in distinguishing between hyperthyroidism and euthyroidism.
Monoclonal antibodies specific for prothrombin fragment 1.2 and their use in a quantitative enzyme-linked immunosorbent assay
Authors: Hursting M J , Butman B T , Steiner J P , Moore B M , Plank M C , Szewczyk K M , Bell M L , Dombrose F A 
Published: January 2020

Abstract
Prothrombin fragment 1.2 (F1.2) is an activation peptide generated during a critical event of blood coagulation, the conversion of prothrombin to thrombin. As a marker of thrombin generation, F1.2 has clinical potential in assessing thrombotic risk and monitoring anticoagulant therapy. In developing a highly specific, monoclonal antibody-based immunoassay of human plasma F1.2, we generated six murine anti-F1.2 monoclonal antibodies, using as immunogen a synthetic peptide (sequence: CGSD-RAIEGR) similar to the unique carboxyl terminus of F1.2. Each antibody bound F1.2 but not prothrombin. Epitope mapping studies with one antibody (5-3B) showed that optimum binding required six to eight amino acids plus a terminal arginine to emulate the F1.2 carboxyl terminus. A quantitative sandwich ELISA for human plasma F1.2 was configured with monoclonal antibody 5-3B as the capture antibody and peroxidase-labeled polyclonal antibodies to the F1.2 amino-terminal region as detector antibodies. Calibrators were prepared by adding purified F1.2, 0-10 nmol/L, to F1.2-depleted plasma. Assay characteristics included the following: mean (+/- SD) analytical recovery of 98% +/- 13%; no interference from lipemia, hemolysis, icterus, or thrombolytic agents; 0.08 nmol/L sensitivity; and mean intra- and interassay imprecision (three lots) &lt; 12% at both low and high concentrations of F1.2.
Multicenter evaluation of Iso-ALP test kit for measurement of bone alkaline phosphatase activity in serum and plasma
Authors: Rosalki S B , Foo A Y , Burlina A , Prellwitz W , Stieber P , Neumeier D , Klein G , Poppe W A , Bodenmüller H 
Published: January 2020

Abstract
A test kit (Iso-ALP, Boehringer Mannheim) for measuring human bone alkaline phosphatase activity in serum or plasma was evaluated in five laboratories in three countries. The assay is based on the principle described by Rosalki and Foo (Clin Chem 1984;30:1182-6) and uses wheat germ lectin to precipitate bone alkaline phosphatase. Residual ALP in the supernate in comparison with total ALP is used to quantify the bone fraction. The imprecision of residual ALP measurement was low (median between-run CV 4.9%) and comparable with that of total ALP. Linearity of precipitation was demonstrable up to a bone ALP activity (diethanolamine buffer 37 degrees C) of 2000 U/L, though a matrix effect was observed for dilutions of high-activity sera in saline or bovine serum albumin. For assaying patients' samples, different batches of lectin demonstrated excellent comparability. Taking electrophoresis as a basis for standardization, we determined that the lectin precipitated approximately 90% of bone ALP, but &lt; 5% of nonbone ALP. From this we derived serum/plasma upper reference limits for bone ALP activity in adults and children.
Clinical and laboratory studies of time-resolved fluorescence immunoassays of thyrotropin and free triiodothyronine
Authors: Taimela E , Aalto M , Koskinen P , Irjala K 
Published: January 2020

Abstract
We evaluated a new time-resolved immunofluorometric assay (TR-IFMA) for thyrotropin (TSH) and a time-resolved fluoroimmunoassay (TR-FIA) for free triiodothyronine (FT3) in serum. Delfia hTSH Ultra is a solid-phase two-site TR-IFMA involving three monoclonal antibodies directed against different antigenic sites on the human TSH molecule. It offers improved analytical (+3 SD of zero) and functional (10% between-assay CV) detection limits of 0.001 and 0.016 mlU/L, respectively. Results of the assay agreed closely with those of a second-generation immunoradiometric assay (TSH-IRMA) for samples with TSH &gt; 0.2 mlU/L (n = 114). The nonparametric reference interval for TSH in euthyroid men and women was 0.5-4.7 mlU/L (n = 200). The TSH concentrations of hyperthyroid subjects (n = 29) were &lt; 0.016 mlU/L (median; range &lt; 0.016-0.063 mlU/L). The Delfia FT3 assay, a solid-phase TR-FIA, is based on the back-titration principle and second-antibody separation. The parametric reference interval for FT3 in euthyroid men and women was 4.2-7.6 pmol/L (n = 320). The FT3 concentration in hyperthyroidism (n = 29) was 23 +/- 22 pmol/L (mean +/- SD; range 7.9-85 pmol/L). These methods offered rapid results (2-4 h for the whole procedure) and were simple to run.
Effects of age, race, sex, and smoking on prothrombin fragment 1.2 in a healthy population
Authors: Hursting M J , Stead A G , Crout F V , Horvath B Z , Moore B M 
Published: January 2020

Abstract
Prothrombin fragment 1.2 (F1.2) is a biomarker of thrombin generation during blood coagulation and has diagnostic potential for assessing thrombotic risk and monitoring anticoagulation therapy. We used a monoclonal antibody-based immunoassay for plasma F1.2 to establish a well-defined reference interval and to evaluate the effects of age, race, sex, and smoking status on F1.2 concentrations in a healthy population. Plasma samples and demographic information were obtained from 357 healthy individuals. F1.2 concentrations more closely followed a lognormal than a gaussian frequency distribution. In a multiple linear-regression model in which the logarithms of F1.2 concentrations were regressed on age, race, sex, and smoking status, the significant explanatory variables were age and, to a lesser extent, sex and smoking. A segmented "hockey stick" regression model indicated that F1.2 concentrations and age were unrelated for individuals &lt; 44 years old but were positively correlated above that age threshold. The estimated 95% tolerance interval (P = 0.95) for F1.2 in healthy individuals &lt; 44 years old (n = 268) was 0.21-2.78 nmol/L. We conclude that age-matched F1.2 reference intervals may be important for studies evaluating the diagnostic utility of F1.2 measurements, and that the clinical relevance of increased thrombin generation during aging warrants further investigation.
Quantitative analysis of serum proteins separated by capillary electrophoresis
Authors: Kim J W , Park J H , Park J W , Doh H J , Heo G S , Lee K J 
Published: January 2020

Abstract
The possibility of open tubular capillary electrophoresis for clinical diagnostic use is examined. Capillary electrophoresis was performed in an untreated 50 microns (i.d.) x 100 cm (65 cm to detector) capillary with detection of absorbance at 200 nm. Conditions for the separation of serum proteins without adsorption to the capillary surface were established. Quantitative analyses of serum samples from 38 patients with liver cirrhosis, nephrotic syndrome, or polyclonal gammopathy by capillary electrophoresis were done and the results were compared with those by conventional agarose gel electrophoresis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. All samples were analyzed in duplicate. We evaluated linearity of response, within-run CV, and the correlation between capillary electrophoresis and agarose gel electrophoresis.
Rapid cycle allele-specific amplification: studies with the cystic fibrosis delta F508 locus
Authors: Wittwer C T , Marshall B C , Reed G H , Cherry J L 
Published: January 2020

Abstract
Rapid cycle DNA amplification is a polymerase chain reaction technique with improved product specificity and cycle times of 20-60 s, allowing complete 30-cycle reactions in 10-30 min. The presence or absence of the delta F508 deletion and wild-type allele was determined in 104 cystic fibrosis patients by rapid cycle DNA amplification. In separate allele-specific assays, sequences on both sides of the delta F508 locus were amplified with the 3' end of a discriminating primer at the delta F508 locus, with either a 3-bp or a 1-bp mismatch. With rapid cycling (35-s cycles), single-base discrimination was achieved over a broad range of annealing temperatures (50 degrees C or lower); with conventional cycling and "hot starts" (160-s cycles), only annealing temperatures of 61-62 degrees C sufficiently discriminated between alleles. With rapid cycling, genotype could still be assessed with annealing temperatures as low as 25 degrees C. We conclude that faster temperature cycling can improve the results of allele-specific amplification.
Pyrophosphatase-based enzyme-linked immunosorbent assay of total IgE in serum
Authors: Peuravuori H , Korpela T 
Published: January 2020

Abstract
Human IgE was purified to near homogeneity by a two-step procedure consisting of immunoaffinity chromatography and high-performance liquid chromatography. Mouse hybridoma cell lines secreting antibodies against IgE were generated. Monoclonal and polyclonal antibodies were used to develop a "sandwich"-type ELISA for determining total IgE in human serum. Inorganic pyrophosphatase (EC 3.6.1.1), an enzyme having a high turnover number, was used as the label. The mean analytical recovery of our ELISA was 95.2% and the results showed good linear correlation with an established RIA of IgE. We found pyrophosphatase to be a good alternative label for use in immunoassays.
Assay of complexed alpha 1-antichymotrypsin in plasma
Authors: Heidtmann H H , Havemann K 
Published: January 2020

Abstract
We introduce an assay to measure complexed alpha 1-antichymotrypsin in human plasma. The assay works on the principle that the target proteinase cathepsin G has a very high affinity to the surface of microtiter plates, even if these surfaces are blocked with albumin and Tween 20. alpha 1-Antichymotrypsin, when complexed to cathepsin G, is thus immobilized and can be detected with specific antibodies. The mean (SD) concentration of alpha 1-antichymotrypsin in 50 healthy individuals was 1.73 (0.58) nmol/L. The detection limit was 0.84 nmol/L. The results of the assay are linear to at least 14 nmol/L. We propose to use this assay for diseases in which increased turnover of alpha 1-antichymotrypsin or cathepsin G can be expected to clarify further the function of this enzyme-inhibitor system.
Measurement of urinary sugars by HPLC in the estimation of intestinal permeability: evaluation in pediatric clinical practice
Authors: Willems D , Cadranel S , Jacobs W 
Published: January 2020

Abstract
Determinations of the permeability of the intestine to various sugars have been used to assess intestinal mucosal abnormalities, but the widespread application of such tests has been prohibited by the complexity of most classically used techniques. In this study, we evaluated the sensitivity and practicability of using HPLC to estimate intestinal permeability, with mannitol and lactulose as mono- and disaccharides, respectively. The results of the permeability tests were compared with those of intestinal biopsy in 20 children. All patients with an abnormal intestinal biopsy showed a low mannitol recovery, and the patients with allergic symptoms showed a high lactulose recovery. Our preliminary data suggest that HPLC is reliable, gives results comparable with those of other methods, and is a practical way to determine intestinal permeability noninvasively.
Enzymatic determination of anti-NAD+ glycohydrolase in serum
Authors: Gella F J , Viver J , Canalias F , Beleta J , Gonzalez-Sastre F 
Published: January 2020

Abstract
A colorimetric method for measuring anti-NAD+ glycohydrolase in human sera has been developed. The assay involves the inhibition of NAD+ glycohydrolase (EC 3.2.2.5) by the antibody and determination of the noninhibited enzyme activity by using an enzymatic amplifying system for NAD+. The assay is easily carried out and has the additional advantage of a direct relationship between signal and antibody concentration. The results obtained for 100 human sera compare favorably with other tests commonly used to obtain evidence of streptococcal infections or their complications, such as the anti-streptolysin O and the anti-DNase B tests.
Effect of double-blind crossover selenium supplementation on biological indices of selenium status in cystic fibrosis patients
Authors: Portal B , Richard M J , Ducros V , Aguilaniu B , Brunel F , Faure H , Gout J P , Bost M , Favier A 
Published: January 2020

Abstract
Twenty-seven cystic fibrosis patients received selenium supplementation (2.8 micrograms of sodium selenite per kilogram of body weight per day) or a placebo. This 5-month trial was conducted as a double-blind, placebo-controlled study. After an interval of 2 months, treatments of the two groups were interchanged (crossed over) for another 5-month period. A group of healthy subjects, living in the same area, was investigated simultaneously. No selenium deficiency was found either in plasma or in erythrocytes before the supplementation. This result was inconsistent with a previous study performed in 1988 in our laboratory. This change in selenium status can be explained by progress in the nutritional nursing care of children and by the addition of selenium to the diet. During the study, selenium concentrations in plasma decreased when patients received placebo treatment and increased during selenium intake. In one of the two groups a similar variation was found for glutathione peroxidase activities in plasma and erythrocytes, whereas erythrocyte selenium was normal and did not change in any group. Nowadays, in the Grenoble area, the selenium status of cystic fibrosis patients is close to normal. Nevertheless, this study indicates a fragile equilibrium, given that selenium concentrations cn be lowered by placebo or mildly increased by supplementation.
Improvement and assessment of enzyme-linked immunosorbent assay to detect low FK506 concentrations in plasma or whole blood within 6 hours
Authors: Wallemacq P E , Firdaous I , Hassoun A 
Published: January 2020

Abstract
FK506, a promising new immunosuppressant, is currently under clinical investigation. Because dose-dependent toxicity is possible, blood concentrations of FK506 should be monitored. We improved the original ELISA of FK506 by shortening the incubation time. With some modification of materials, results are obtained within 6 h instead of 2 days, with similar or even better precision. Internal and external quality-control programs showed that our results correlated satisfactorily both with values determined by the original method and the theoretical expected values. Either plasma (detection limit 0.1 microgram/L) or whole-blood (detection limit 1 microgram/L) samples can be used. The sensitivity of the method makes it particularly useful for accurate pharmacokinetic studies or measurement of low blood concentrations. Twenty-four drugs and nine biological variables showed no significant interference on the assay. Study of the concentration- and temperature-dependent distribution of FK506 shows that the drug is largely bound to erythrocytes (ratio of blood to plasma concentrations is 10-40); as the erythrocytes become saturated, more of the drug is found in the plasma. Plasma concentrations may vary according to the blood temperature. We conclude that whole blood should be used for FK506 monitoring, as it is for monitoring cyclosporine.