bluuebunny/crossref_metadata_2025_split huggingface dataset:
Current analytical approaches to measuring blood analytes
Authors: Burritt M F 
Published: January 2020

Abstract
In recent years, laboratory testing in the critical-care setting has increased, a trend due, in part, to the evolution of electrochemical sensors. Various innovations have extended sensor lifetimes, reduced sensor maintenance, and led to the development of single-use and unit-use disposable sensors. These sensor technologies allow the accurate and precise determination, either at or near the bedside, of several analytes including pO2, pCO2, pH, Na, K, Cl, ionized calcium, hematocrit, total hemoglobin, and glucose. Use of these new systems, however, has raised new issues regarding sensor calibration and sample handling and collection. The number of direct-reading analyzers for electrolyte determinations has also increased dramatically. Issues regarding calibration of ion-selective electrodes (ISEs) for Na/K have also been raised after demonstrations of between-instrument variation. Recently, collaborative efforts between eight ISE instrument manufacturers and the National Institute of Standards and Technology resulted in the development of a Standard Reference Material, SRM 956, for the purpose of standardizing direct-reading Na/K ISEs to the flame photometer. Other widely used technologies that provide noninvasive, continuous monitoring include pulse oximetry and transcutaneous gas electrodes. These trends are expected to continue and to produce a new generation of electrochemical and optical sensors.
Through a glass darkly: the lung as a window to monitor oxygen consumption, energy metabolism, and severity of critical illness
Authors: Siegel J H 
Published: January 2020

Abstract
Medical diagnosis and therapeutic monitoring for critical illness require adaptation of laboratory analyses to the bedside. These are greatly helped by the modification of physiological and biochemical data-acquisition techniques to increase the number and accuracy of noninvasive variables that can be obtained from the patient. This paper addresses the choice of noninvasive measurements and is largely directed at the assessment of oxygen debt as a measure of the severity of ischemic and septic metabolic processes. Especially considered are those noninvasive measures of cardiorespiratory adequacy, key variables that need to be considered together with the metabolic function to adequately reflect the patient's state of accommodation to critical illness or injury. I describe a noninvasive sensor system linked to a computer work-station that functions in a pattern recognition mode to permit classification of patients as to the type and severity of their physiological adaptation. This system can serve as a sophisticated bedside monitor of the severity of the patient's condition, as a guide to therapy.
Orchestrating a dignified death in the intensive-care unit
Authors: Youngner S J 
Published: January 2020

Abstract
Approximately 2 million people die in the United States each year, 80% of them in acute- or chronic-care institutions. Physicians now have at their disposal interventions that can postpone death in almost every instance. In these circumstances the critical-care physician cannot avoid the responsibility of orchestrating death by balancing factors such as the patient's autonomy and best interests, medical uncertainty and futility, and notions of "passive" (permissible) and "active" (forbidden) euthanasia. Pressures to make decisions unilaterally and without patient input threaten to undermine important physician/patient/family dialogue. On the other hand, the fact that medical resources are becoming increasingly expensive and scarce will inevitably lead to rationing. The critical-care physician will be caught in the middle--orchestrating clinical care to balance the interests of individual patients and families against those of the larger community.
Robotic transportation
Authors: Lob W S 
Published: January 2020

Abstract
Mobile robots perform fetch-and-carry tasks autonomously. An intelligent, sensor-equipped mobile robot does not require dedicated pathways or extensive facility modification. In the hospital, mobile robots can be used to carry specimens, pharmaceuticals, meals, etc. between supply centers, patient areas, and laboratories. The HelpMate (Transitions Research Corp.) mobile robot was developed specifically for hospital environments. To reach a desired destination, Help-Mate navigates with an on-board computer that continuously polls a suite of sensors, matches the sensor data against a pre-programmed map of the environment, and issues drive commands and path corrections. A sender operates the robot with a user-friendly menu that prompts for payload insertion and desired destination(s). Upon arrival at its selected destination, the robot prompts the recipient for a security code or physical key and awaits acknowledgement of payload removal. In the future, the integration of HelpMate with robot manipulators, test equipment, and central institutional information systems will open new applications in more localized areas and should help overcome difficulties in filling transport staff positions.
Laboratory robotics and artificial intelligence
Authors: Isenhour T L , Marshall J C 
Published: January 2020

Abstract
Intelligent robots, which incorporate artificial intelligence in their controlling software, are the next step in bringing the laboratory robot to its full potential. The areas currently under study in our laboratory are improved user interfaces for laboratory robotics, the integration of object-oriented databases into robot control programs, and strategies to optimize multi-step procedures. The ultimate goal of this work is the Standard Robotics Method. The Standard Robotics Method we envision would allow a robotic method to be transferred from one laboratory to another.
A standard clinical instrument interface for robotic applications
Authors: Margrey K S , Martinez A , Vaughn D P , Felder R A 
Published: January 2020

Abstract
Many clinical laboratory instruments are not designed for robotic compatibility, hence the need for standardization of data communications and analyzer interface hardware. We developed an interface with supporting software that simplifies communication between a microcomputer and clinical instruments. Our interface establishes a standardized bidirectional communications protocol, which is useful in many clinical laboratory robotic projects. Instruments targeted for interfacing require no prior on-board communications capabilities. Additionally, modifications to the clinical instrument are minimized. Once installed, the interface translates input commands to codes or actions recognizable by the analyzer. Features not normally available to the user, such as electrode real-time response and full instrument status, are also reported by the interface, thereby establishing a remote monitor and control mechanism for the interfaced instrument. We have written an operating system to control the interface microcomputer, which in turn commands and monitors the clinical analyzer. A host computer controls the information flow to the interface and provides (a) requests to the interface for instrument operation and status and (b) commands to the interface to initiate the desired instrument operation. This arrangement maintains complete instrument functionality as designed by the manufacturer while allowing remote monitoring and operation of the instrument.
Characterization and rapid diagnostic analysis of DNA polymorphisms closely linked to the cystic fibrosis locus
Authors: Horn G T , Richards B , Merrill J J , Klinger K W 
Published: January 2020

Abstract
Six genetic polymorphisms, closely linked to the cystic fibrosis gene and useful in clinical linkage analysis, have been characterized and converted to a more rapid form of assay. Sequences flanking the metD (Ban I), metH (Msp I), XV-2c (Taq I), KM.19 (Pst I), MP6d-9 (Msp I), and J3.11 (Msp I) polymorphic restriction sites have been determined and used to design specific polymerase chain reaction (PCR) amplification primers and allele-specific oligonucleotide probes. All six of these polymorphisms were found to involve single-base alterations, and the XV-2c polymorphism was found to lie within an Alu repeat segment. These PCR-based tests, in conjunction with the CS.7 (Hha I) assay described elsewhere (Stanier P et al. Hum Genet 1988;80:309-10; Williams C et al. Lancet 1988;ii:102-3), provide a convenient, rapid, and reliable method of haplotype and linkage analysis, clinically useful in those situations where direct detection of mutations is not possible.
Measurement of serum bone gla-protein (BGP) in humans with an ovine BGP-based radioimmunoassay
Authors: Pastoureau P , Delmas P D 
Published: January 2020

Abstract
Most RIAs of serum bone gla-protein (BGP; also called osteocalcin) used for clinical investigation are based on bovine BGP for standard, tracer, and immunogen because of the homology between bovine and human BGP. However, ovine BGP differs from human BGP by only five amino acids, being identical from residues 11 to 49, as compared with homology at residues 20-49 between bovine and human BGP. In screening various anti-ovine BGP polyclonal anti-sera we selected one (R310) that exhibits apparently complete cross-reactivity with human BGP, as assessed by dilutions of 13 human sera from normal subjects and from patients with bone disease. This RIA gave a 42% binding at a 10,000-fold final dilution, with intra- and interassay variations less than 7% and 11%, respectively. Gel-filtration chromatography of human serum showed a single immunoreactive peak. Synthetic fragments of human BGP 1-10, 7-19, 25-37, and 37-49 were not recognized by R310, suggesting that either a mid-molecule region or a conformational epitope was its target. Using this RIA, we determined that serum BGP increased with age in women (P less than 0.02), by a mean of 90% from ages 30 to 70 years. Serum BGP was also increased in patients with primary hyperparathyroidism, renal osteodystrophy, and Paget's disease. In contrast with the "normal" concentrations of BGP detected with an anti-bovine BGP antiserum (R102), serum BGP was increased in patients with postmenopausal osteoporosis as measured with the R310 ovine assay, suggesting a greater sensitivity for the latter assay.
Effect of reticulocytosis on lactate dehydrogenase isoenzyme distribution in serum: in vivo and in vitro studies
Authors: Kazmierczak S C , Castellani W J , Van Lente F , Hodges E D , Udis B 
Published: January 2020

Abstract
We investigated the effect of reticulocytosis on the lactate dehydrogenase (LD; EC 1.1.1.27) isoenzyme LD1/LD2 ratio in patients with and without evidence of hemolytic disease. Analysis of sera from patients with reticulocytosis and in vivo hemolysis showed a mean LD1/LD2 ratio of 0.92 compared with a ratio of 0.69 in patients with in vivo hemolysis and normal reticulocyte counts. Determination of LD isoenzymes in erythrocyte lysate revealed significantly increased LD1/LD2 ratios for patients with marked reticulocytosis compared with those for patients with normal-to-minimal increases in reticulocytes. Finally, separation of mature erythrocytes and reticulocytes by flow cytometry revealed marked differences in the LD1/LD2 isoenzyme distribution between these two cell types. The ability of hemolysis to cause a "flipped" LD1/LD2 ratio is dependent on the proportion of the hemolyzed cells that are reticulocytes.
Electrode measurement of glucose and urea in undiluted samples
Authors: Gourmelin Y , Gouget B , Truchaud A 
Published: January 2020

Abstract
The development of ion-selective electrodes (ISEs) for electrolyte measurements necessitates a re-evaluation of the biological and clinical interpretation of a result. In pathological situations (e.g., hyperlipidemia and hyperproteinemia) direct potentiometry is the method of choice for ion measurements in blood. However, the "plasma water effect" exists also in normal samples, requiring new reference values for physiological ranges. A compromise between medical and instrumentation workers retained the old reference values (flame photometry for Na+ and K+) by introducing correction factors into the ISE instruments, so that the results for direct ISE and flame photometry are the same for "normal" samples. Analyses of "abnormal" samples will reveal biases between the two methods. Now, a new generation of electrodes for assaying additional metabolites reopens the issue. Although classical methods measure a quantity of substance in a predetermined volume of sample, the majority of the substance is usually in the aqueous phase, and the volumes occupied by lipid and protein are not taken into consideration. In evaluating the NOVA 12 instrument (NOVA Biomedical), using electrodes for direct measurement in serum or plasma of Na, K, Cl, total CO2, urea, and glucose, we have demonstrated the inadequacy of classical measurements of urea and glucose, especially in pathological situations characterized by a large variation in the plasma water fraction.
Molar absorptivities of bilirubin (NIST SRM 916a) and its neutral and alkaline azopigments
Authors: Doumas B T , Perry B W , McComb R B , Kessner A , Vader H L , Vink K L , Koedam J C , Paule R C 
Published: January 2020

Abstract
Three laboratories in the U.S. and two in the Netherlands determined molar absorptivities (epsilon) of Standard Reference Material (SRM) 916a Bilirubin from the National Institute of Standards and Technology. In caffeine reagent the average epsilon values were 50,060 and 48, 980 L.mol-1.cm-1 at 432 and 457 nm, respectively. The epsilon value of the blue azopigment, obtained with the Reference Method for total serum bilirubin, was 76,490 L.mol-1.cm-1 at 598 nm. When the addition of alkaline tartrate was omitted, the molar absorptivity of the red azopigment was 56,600 L.mol-1.cm-1 at 530 nm.
Effect of calibration on dispersion of glycohemoglobin values determined by 111 laboratories using 21 methods
Authors: Weykamp C W , Penders T J , Muskiet F A , van der Slik W 
Published: January 2020

Abstract
One hundred eleven laboratories, using 21 different methods based on five different principles, determined glycohemoglobin (GHb) percentages in two identical series of six lyophilized hemolysates and three similarly processed calibrators, distributed 3 months apart. To assign GHb percentages to calibrators, we used HbA1c results from nine participants who used the Bio-Rad Diamat high-performance liquid chromatographic method. Three-point calibration with assigned values improved mean intralaboratory variation (CV) from 6.6% to 3.5%. For samples with low (5.5%) and high (14.1%) GHb percentages, respectively, calibration decreased interlaboratory variation per method (from 10% to 4% and from 6% to 3%), inter-method variation (from 18% to 4% and from 16% to 3%), and overall interlaboratory variation (from 25% to 7% and from 15% to 4%). Without calibration, 71% of the laboratories did not meet the clinically desirable intralaboratory CV of 3.5%; calibration reduced this proportion to 39%. We conclude that, irrespective of the analytical method used, calibration greatly reduces all sources of GHb variation.
Concanavalin A-bound selenoprotein in human serum analyzed by graphite furnace atomic absorption spectrometry
Authors: Daher R , Van Lente F 
Published: January 2020

Abstract
We developed an assay for the direct determination of selenium in serum with a Perkin-Elmer Model 4100ZL Zeeman atomic absorption spectrometer and Ag-Cu-Mg modifier. We used this assay to analyze concanavalin A-bound selenoprotein (CABSP) in human serum after concanavalin A (ConA) affinity chromatography. The CABSP was identified as a single-chain glycoprotein of 57.3 kDa. Carbohydrate units were N- and O-linked to the protein. The selenium moiety was selenocysteine. Total selenium, glutathione peroxidase (GPX; EC 1.11.1.9), ConA-bound selenium (CABS), and alpha 1-acid glycoprotein (AAG) were determined in normal subjects and patients with various pathological conditions. CABS accounted for 44.1% +/- 6.3% of total selenium in sera from normal subjects and 46.5% +/- 3.9% to 55.1% +/- 8.1% in sera from patients with a variety of diseases. Total selenium in serum was well correlated with serum CABS (r = 0.860), but not with serum GPX activity (r = 0.117), for all patients studied. Serum CABS increased in normal subjects after selenium supplementation. Serum CABSP did not behave as an acute-phase reactant, compared with AAG.
Semiautomated detection of human papillomavirus DNA of high and low oncogenic potential in cervical smears
Authors: Terry G , Ho L , Szarewski A , Cuzick J 
Published: January 2020

Abstract
Detection of DNA from human papillomaviruses (HPV) of high and intermediate oncogenic risk in cervical smears may predict the presence of cervical cancer or may indicate precancerous changes. Here we describe a semiautomated polymerase chain reaction system for the detection and classification of HPV DNA that is present in clinically significant amounts in routine cervical scrapes.
Felbamate measured in serum by two methods: HPLC and capillary electrophoresis
Authors: Shihabi Z K , Oles K S 
Published: January 2020

Abstract
We have developed two methods for determining serum concentrations of felbamate, a new anticonvulsant drug. The first method is based on protein precipitation with acetonitrile, followed by HPLC. The between-run CV for this method is 5.7% (mean 55 mg/L), and the linearity extends from 5 to 175 mg/L. Results by this method compared well with those by an HPLC method based on chloroform extraction (r = 0.98, n = 21). In the second method, based on micellar electrokinetic capillary chromatography, the drug is measured by capillary electrophoresis with direct injection of serum. This method can be completed in 5 min compared with 12 min for the HPLC method, and there is no need for sample extraction. The between-run CV is 5.2% (mean 58 mg/L) and the linearity range is 5-160 mg/L. Results of this direct method correlated well (r = 0.98, n = 37) with those by the HPLC assay. The mean trough serum concentration of felbamate in 123 patients taking this drug was 44.9 mg/L (range 12-129 mg/L).
Allowable imprecision for laboratory tests based on clinical and analytical test outcome criteria
Authors: Westgard J O , Seehafer J J , Barry P L 
Published: January 2020

Abstract
The allowable imprecision for laboratory tests has been estimated from criteria based on clinical and analytical test outcome. The analytical outcome criteria studied are the Clinical Laboratory Improvement Amendments (CLIA) criteria for proficiency testing. The clinical outcome criteria are estimates of medically significant changes in test results taken from a study in the literature. The estimates of allowable imprecision were obtained from quality-planning models that relate test outcome criteria to the allowable amount of imprecision and inaccuracy and to the quality control that is necessary to assure achievement of the desired outcome criteria in routine operation. These operating specifications for imprecision are consistently more demanding (require lower CVs) than the medically useful CVs originally recommended in the literature because the latter do not properly consider within-subject biological variation. In comparing estimates of allowable imprecision, the CLIA outcome criteria are more demanding than the clinical outcome criteria for aspartate aminotransferase (asymptomatic patients), cholesterol, creatinine (asymptomatic patients), glucose, thyroxine, total protein, urea nitrogen, hematocrit, and prothrombin time. The clinical outcome criteria are more demanding for bilirubin (acute illness), iron, potassium, urea nitrogen (acute illness), and leukocyte count. The estimates of allowable imprecision from analytical and clinical outcome criteria overlap for aspartate aminotransferase (acute illness), bilirubin (asymptomatic patients), calcium, creatinine (acute illness), sodium, triglyceride, and hemoglobin.
Bilirubin production in healthy term infants as measured by carbon monoxide in breath
Authors: Stevenson D K , Vreman H J , Oh W , Fanaroff A A , Wright L L , Lemons J A , Verter J , Shankaran S , Tyson J E , Korones S B 
Published: January 2020

Abstract
To describe total bilirubin production in healthy term infants, we measured the end-tidal breath CO, corrected for ambient CO (ETCOc), with an automated sampler and electrochemical (EC) CO instrument. For infants of mothers with a negative Coombs' test, the ETCOc was 1.3 +/- 0.7 microL/L (n = 397) and the serum bilirubin on day 3 postpartum was 73 +/- 35 mg/L (n = 381). In contrast, the ETCOc for infants with ABO or Rh incompatibility, a positive direct Coombs' test, and bilirubin &gt; 130 mg/L (n = 9) was significantly higher, 1.8 +/- 0.8 microL/L, than for those who had a positive Coombs' test result but whose bilirubin was &lt; or = 130 mg/L (n = 12), 1.0 +/- 0.5 microL/L (P &lt; 0.05). At 2 to 8 h postpartum seven term babies from mothers with insulin-dependent diabetes had ETCOc of 1.8 +/- 0.7 microL/L, significantly higher than that in the other term infants [1.3 +/- 0.7 microL/L (n = 390), P &lt; 0.04]. Their bilirubin concentration at 72 +/- 12 h was also higher: 121 +/- 45 mg/L (n = 7) vs 73 +/- 34 mg/L (n = 374; P = 0.03). We conclude that ETCOc measurements may be helpful in understanding the mechanisms of jaundice in healthy term infants in a variety of conditions.
Systematic differences between commercial immunoassays for free thyroxine and free triiodothyronine in an external quality assessment program
Authors: Zucchelli G C , Pilo A , Chiesa M R , Masini S 
Published: January 2020

Abstract
Data collected in a national external quality assessment program for free thyroxine (fT4) and free triiodothyronine (fT3) were analyzed to evaluate the performance of 10 method/kits with 26 control samples distributed to approximately 170 laboratories. The control materials were normal serum pools, pooled sera supplemented with thyroid hormones, a pregnancy serum pool, serum pooled from patients with familial dysalbuminemic hyperthyroxinemia (FDH), and a normal serum pool progressively diluted. The between-laboratory variability (CV) was approximately constant in normal and supplemented pools for fT4 (15.3%) and fT3 (24.0%) but markedly increased in diluted, pregnancy, and FDH pools (21.9-35.2% for fT4 and 28.6-66.5% for fT3) because of increases in systematic between-kit differences in control samples with altered binding-protein capacity. Moreover, free hormone concentrations measured in progressively diluted sera averaged lower than in undiluted samples. This decrease of concentration was less for back-titration or labeled-antibody techniques and greater for labeled-analog methods; only the method involving adsorption to cross-linked dextran (Sephadex) was unaffected by dilution. Evaluation of the reproducibility of the method/kits showed between-assay, between-laboratory precision ranging from 7.8% to 17.0% for fT4 and from 9.8% to 20.3% for fT3.