Abstract：
:Various laboratories have reported endogenous digoxin-like immunoreactive factor(s) (DLIF) in blood from patients in renal failure or liver failure, from newborn infants, and from third-trimester pregnant women. Similar immunoreactivity has been detected in amniotic fluid, in cord blood, and in urine and serum from normal subjects. The factor(s) giving rise to this immunoreactivity cross react with antibodies used in many currently available immunoassays for digoxin, sometimes causing apparent digoxin concentrations exceeding the therapeutic range obtained for exogenous digoxin, with consequent errors in measurement and in subsequent clinical interpretation of digoxin results. Here, I summarize findings in our laboratory and those of others. DLIF evidently exist in three states in serum: tightly protein-bound, weakly protein-bound, and unbound (free). In normal subjects, greater than 90% of the total DLIF in serum is tightly but reversibly bound to serum proteins and is not readily detectable by direct measurement of digoxin in serum with conventional immunoassays. However, there seems to be a redistribution of the more weakly bound and unbound components in patients with renal failure, pregnant women, and newborns. The increased values detected in these groups are ascribable to increased amounts of weakly bound and unbound DLIF rather than to increased total DLIF. Carrier proteins may play a prominent role in the transport of these factors in blood. I discuss the potential physiological and pharmacological implications of detecting endogenous immunoreactive factors that cross react with antibodies to drugs.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Valdes R Jrsubject
Has Abstractpub_date
1985-09-01 00:00:00pages
1525-32issue
9eissn
0009-9147issn
1530-8561journal_volume
31pub_type
杂志文章,评审abstract：BACKGROUND:Advances in the biological sciences and technology are providing molecular targets for diagnosing and treating cancer. Current classifications in surgical pathology for staging malignancies are based primarily on anatomic features (e.g., tumor-node-metastasis) and histopathology (e.g., grade). Microarrays to...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：2002-08-01 00:00:00
abstract：:We report results for adjusted ionized calcium (at pH 7.4) and actual ionized calcium (at actual pH) in capillary blood from 183 patients with disorders of calcium metabolism (primary hyperparathyroidism, secondary hyperparathyroidism of malabsorption, primary hypoparathyroidism, Paget's disease, acromegaly, hypercalc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:Serial measurements of the bone and fetal intestinal isoenzymes of alkaline phosphatase (EC 3.1.3.1) in the plasma of 43 term and 43 preterm infants, from birth to six weeks later, indicate that the bone isoenzyme gradually increases over this period in both preterm and term infants fed with unsupplemented commercial ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：BACKGROUND:The next-generation, high-sensitivity cardiac troponin assays can measure quantifiable concentrations of cTn in a majority of individuals, but there are few studies assessing these assays for risk stratification. The present study was undertaken to determine if a research hs-cTnI assay can be useful for pred...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.127241
更新日期：2009-10-01 00:00:00
abstract：:Single-strand conformation polymorphism (SSCP) analysis is widely used to prescreen mutations in p53 gene. However, standardization of SSCP to detect p53 mutations has rarely been pursued so far. We have developed complete conditions for a temperature-controlled nonradioactive SSCP for mutation detection in amplified ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：:We studied the specificity of kinetic methods of analysis, with emphasis on creatinine determination. The error contributed by an interferent that reacts with the analytical reagent and absorbs at the wavelength of analysis is shown to be related to the ratio of the equilibrium absorbances of the analyte and interfere...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-04-01 00:00:00
abstract：:We compared the effects of freezing serum on the determination of high-density lipoprotein (HDL) subfractions by two dual-precipitation methods, heparin and manganese chloride/dextran sulfate (HM/DS) (Gidez et al., J Lipid Res 1982;23:1206-23) and DS/DS (Warnick et al., Clin Chem 1982;28:1574), and by ultracentrifugat...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-09-01 00:00:00
abstract：:This communication describes and evaluates an improved routine methodology for quantitating clinical proteinuria. Based on investigations of Piscator and of Savory et al., a modified Tsuchiya's reagent (ethanolic HCI-phosphotungstic acid) is used to precipitate proteins at 56 degrees C, followed by biuret spectrophoto...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
abstract：:Using 123 specimens, we compared the concordance of three different methods for determining glycohemoglobin (GHb): the Diamat (Bio-Rad Laboratories), an automated analyzer measuring HbA1c by cation-exchange chromatography; an assay with the IMx analyzer (Abbott Laboratories), based on boronate affinity binding; and an...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-02-01 00:00:00
abstract：:We describe a simple and convenient method for processing small amounts of tissue samples for trace-metal measurements by atomic absorption spectrometry, by use of a modified Parr microwave digestion bomb. Digestion proceeds rapidly (less than or equal to 90 s) in a sealed Teflon-lined vessel that eliminates contamina...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
abstract：:The present assay was developed for quantifying midazolam in plasma of patients hospitalized in intensive-care units or undergoing anesthesia and receiving many other drugs as well. Plasma samples are alkalinized with NaOH and midazolam is extracted into n-hexane. The organic phase is evaporated and reconstituted in n...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-04-01 00:00:00
abstract：:An oligonucleotide "melting" procedure was developed whereby we can monitor for a sequence heterogeneity in the gene for apolipoprotein E production. Two oligonucleotides were synthesized, one recognizing the common epsilon 3 allele but not the common epsilon 2 allele, the other recognizing the epsilon 2 allele but no...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-07-01 00:00:00
abstract：:We examined the changes in sensitivity and specificity that would occur with alterations in the sample-collection schedule and (or) cutoff criterion for the increase in hydrogen concentration in breath after administration of doses of lactose in the dietary range. In a breath-analysis test to classify individuals as l...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:Measurement of serum ascorbate may be useful in long-term population studies because of the possible influence of ascorbate on numerous physiological factors. We describe an automated method for determining ascorbate in serum and urine by using the reduction of ferric iron by ascorbate and the formation of a color bet...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-09-01 00:00:00
abstract：:Numerous papers have been written to show which combinations of Shewhart-type quality-control charts are optimal for detecting systematic shifts in the mean response of a process, increases in the random error of a process, and linear drift effects in the mean response across the assay batch. One paper by Westgard et ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-08-01 00:00:00
abstract：:This improved assay of rheumatoid factors in serum, described here for use with the Baker "Encore" centrifugal analyzer, is efficient, with 250-sample throughput per hour; reproducible, with between-batch CV = 5% and within-batch CV = 2% (mid-assay range); and results correlate well (r = 0.9) with those by other metho...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-02-01 00:00:00
abstract：:We determined the urinary excretion of 5-fluorouracil (5FU) and its metabolites during six days of chemotherapy, using the non-invasive approach of 19F nuclear magnetic resonance. With this method, which requires no labeled drug, one can study the biological sample directly and simultaneously identify and quantify all...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-06-01 00:00:00
abstract：BACKGROUND:Near-infrared spectroscopy is proposed as a method for providing real-time urea concentrations during hemodialysis treatments. The feasibility of such noninvasive urea measurements is evaluated in undiluted dialysate fluid. METHODS:Near-infrared spectra were collected from calibration solutions of urea prep...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-01-01 00:00:00
abstract：:In "flow-injection analysis," the sample is inserted into a stream of reagent by use of a sample-injection valve. Mixing occurs downstream from the valve in a coil of tubing. With chemiluminescence detection this coil is positioned in front of a photomultiplier. We have evaluated the system for detection of hydrogen p...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-09-01 00:00:00
abstract：:We assessed the LKB "Delfia" (time-resolved dissociation-enhanced lanthanide fluoroimmunoassay) and the Amersham "Amerlite" (enhanced luminescent immunometry) assays of thyrotropin in serum. Both assays are sensitive (respective detection limits: 0.02 and 0.04 milli-int. unit/L) and have very good within- and between-...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-08-01 00:00:00
abstract：:We describe a new, specific, quantitative method for fecal blood, based on conversion of nonfluorescing heme to fluorescing porphyrins, that obviates serious deficiencies inherent in currently used tests. A two-reagent system is used to determine the two hemoglobin-related fractions that are found in feces. The hot ci...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-12-01 00:00:00
abstract：BACKGROUND:Lead is an environmental pollutant, and human exposure is assessed by monitoring lead concentrations in blood. Because the main source of environmental exposure has been the use of leaded gasoline, its phase-out has led to decreased lead concentrations in the general population. Therefore, validated analytic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.029223
更新日期：2004-08-01 00:00:00
abstract：:Hemostasis is initiated by injury to the vascular wall, leading to the deposition of platelets adhering to components of the subendothelium. Platelet adhesion requires the presence of von Willebrand factor and platelet receptors (IIb/IIIa and Ib/IX). Additional platelets are recruited to the site of injury by release ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：2000-08-01 00:00:00
abstract：:The new oral formulation of cyclosporine (CsA), Neoral (CsA-N), results in increased area under the curve (AUC) and decreased intra- and interindividual variation in blood concentrations and other pharmacokinetic (PK) parameters when compared with the current Sand-immune (CsA-S) formulation. The present study examines...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-01-01 00:00:00
abstract：:Several aspects of mass spectrometry and gas chromatography-mass spectrometry are reviewed, including ionization methods, repetitive scanning, selected ion monitoring, and stable isotope measurement. I discuss the application of these and other mass spectrometry methods to the investigation of compound classes relevan...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-06-01 00:00:00
abstract：BACKGROUND:Noninvasive prenatal diagnosis of monogenic disorders using maternal plasma and targeted massively parallel sequencing is being investigated actively. We previously demonstrated that comprehensive genetic diagnosis of a Duchenne muscular dystrophy (DMD) patient is feasible using a single targeted sequencing ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2014.236380
更新日期：2015-06-01 00:00:00
abstract：BACKGROUND:Next generation sequencing (NGS)-based assays continue to redefine the field of genetic testing. Owing to the complexity of the data, bioinformatics has become a necessary component in any laboratory implementing a clinical NGS test. CONTENT:The computational components of an NGS-based work flow can be conc...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2014.224360
更新日期：2015-01-01 00:00:00
abstract：:We describe an automated assay of glycohemoglobin performed with the Abbott Vision analyzer. The assay is based on batch affinity-extraction with 3-aminophenylboronic acid-derivatized agarose beads. Reagents are packaged in a disposable test pack. Whole-blood specimens are hemolyzed with saponin within a glass capilla...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-12-01 00:00:00
abstract：BACKGROUND:Paraoxonase may protect lipoproteins and cell membranes from peroxidation, and alterations in the activity of this enzyme have been associated with some chronic diseases. Serum paraoxonase appears to be mainly under genetic control, but some studies suggest that environmental factors may also modulate its ac...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.9.1491
更新日期：2003-09-01 00:00:00
abstract：:Total protein (TP), albumin (Alb), transferrin (TRF), retinol-binding protein (RPB), N-acetyl-beta-glucosaminidase (NAG), alanine aminopeptidase (AAP), gamma-glutamyltransferase (GGT), and creatinine (Cr) were measured in random (untimed) urine samples from 29 nonpregnant women and from pregnant subjects (11 in the fi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-09-01 00:00:00
