bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiac troponin-I is not expressed in fetal and healthy or diseased adult human skeletal muscle tissue
Authors: Bodor G S , Porterfield D , Voss E M , Smith S , Apple F S 
Published: January 2020

Abstract
Cardiac troponin-I (cTnI) is not found in sera of patients with skeletal muscle disease in the absence of myocardial injury. It is not known, however, whether trace amounts of cTnI are expressed in regenerating human skeletal muscle, as has been observed with creatine kinase MB. Using immunohistochemical and biochemical techniques, we investigated cTnI expression in various human muscle tissues: human heart tissue (n = 5), normal adult skeletal muscle (n = 3), and fetal heart (n = 3) and skeletal muscle (n = 3) obtained, respectively, during heart transplant, from autopsy, or from a tissue bank. Specimens from diagnostic tissue biopsies were used as diseased skeletal muscle: polymyositis (PM), n = 13; Duchenne muscular dystrophy (DMD), n = 6. Frozen sections 8 microns thick were stained immunohistochemically for either cTnI or TnI (cardiac or skeletal) by using monoclonal antibodies (MAb) 2B1.9 (cTnI specific) or 3C5.10 (reactive with all TnI isoforms), respectively. cTnI was measured in tissue homogenates by an immunofluorometric assay. Cardiac muscle was stained by both MAbs. Normal fetal and adult skeletal muscle, and samples from all of the PM and DMD patients, stained only with the nonspecific MAb (3C5.10), confirming the sole presence of skeletal TnI. No cTnI was detectable by immunoassay in any skeletal muscle sample. We conclude that cTnI is not expressed in human skeletal muscle during development or during regenerative muscle disease processes such as PM or DMD.
Plasma alpha-glutathione S-transferase assessed as a marker of liver damage in patients with chronic hepatitis C
Authors: Vaubourdolle M , Chazouillères O , Briaud I , Legendre C , Serfaty L , Poupon R , Giboudeau J 
Published: January 2020

Abstract
alpha-Glutathione S-transferase (alpha-GST; EC 2.5.1.18) has been advocated as a better marker of hepatocellular damage than the transaminases in toxic and autoimmune hepatitis. We have assessed the potential interest of plasma alpha-GST determination in 94 anti-hepatitis C virus-positive patients with histologically proven chronic hepatitis C (34 women, 60 men, ages 40.0 +/- 11.9 years). Blood samples were assayed for aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase, alkaline phosphatase, and alpha-GST on the same day a liver biopsy was performed. alpha-GST concentrations were significantly above reference values in 64% of patients (compared with 58% for AST, 68% for ALT), and this increase was seen in 52% of patients with normal values for transaminases and a Knodell score &gt; 3. Furthermore, there was a significant correlation between alpha-GST and lobular necrosis score (r = 0.31; P &lt; 0.01). Our findings suggest that association of plasma alpha-GST with ALT may improve the biochemical assessment of liver damage in patients with chronic hepatitis C.
Time-resolved immunofluorometric assay of p53 protein
Authors: Levesque M A , D'Costa M , Angelopoulou K , Diamandis E P 
Published: January 2020

Abstract
A common feature of human tumor tissue is mutant p53 protein accumulation. Here we evaluate a new "sandwich" immunoassay for p53 protein incorporating modifications to a previously reported method, including the use of microtiter plates coated directly with the anti-p53 monoclonal antibody DO-1, a detergent- and mouse serum-containing sample diluent, and a labeled secondary antibody diluent containing goat serum. The use of CM-1 antiserum to probe the immunocaptured p53 and the detection of bound complexes by a labeled secondary antibody allows coupling to a time-resolved fluorescence detection system. The new assay yielded p53 concentrations comparable with those by the previous assay for breast tumor cytosols (n = 198), nondiseased breast tissues (n = 70), and five transformed cell lines, but showed differences in p53 values measured in sera from patients without cancer (n = 78). These serum differences were found to reflect nonspecific interferences affecting the original method, which implies that the new immunoassay has improved specificity for serum p53 quantification.
Cobas Integra: clinical laboratory instrument with continuous and random-access capabilities
Authors: Palmer S M , Kaufman R A , Salamone S J , Blake-Courtney J , Bette W , Wahl H P , Furrer F 
Published: January 2020

Abstract
The Cobas Integra from Roche Diagnostic Systems is a new clinical laboratory analyzer with continuous and random-access features for routine chemistries, specific proteins, electrolytes, hormones, therapeutic drugs, and drugs of abuse. The system maintains 68 test-specific reagent cassettes on board, along with multiple ion-selective electrodes (ISEs) for electrolyte determinations. This gives the Cobas Integra the capability of analyzing as many as 72 analytes without having to load additional reagents. We describe the basic analyzer configuration and the subsystems for absorbance, fluorescence polarization, and ISE measurements. Performance characteristics for precision, methods comparison, and on-board stability are given for assays representative of the various test groups. The 29 Cobas Integra tests evaluated in the present study show good agreement (r &gt; or = 0.98 and slopes generally 0.90 to 1.12) with the respective methods available on either the Olympus AU5000, Hitachi 911 or 717, Behring BNA, or Abbott TDx systems. Total assay precision (CV) ranged from 0.8% to 8.5%, and calibration curves were stable for as long as 20 weeks. Test throughput, which is dependent on pipetting sequence, was determined to be up to 600 tests per hour without ISE and up to 750 tests per hour with ISE; the time to first result was 2.0-10.0 min.
Biomarkers in epidemiology
Authors: Grandjean P 
Published: January 2020

Abstract
A biomarker is a measurable event occurring in a biological system, such as the human body. In environmental epidemiology, a biomarker represents a subclinical and reversible change; it is not a diagnostic test, but an indicator that an early change has occurred that could later lead to clinical disease. Although some biomarkers may belong to more than one class, they are often separated into biomarkers of exposure, biomarkers of effect, and biomarkers of susceptibility. Biomarkers can be used to classify and quantify environmental exposures and their related effects, and many methods may be applicable in toxicological experiments as well as in epidemiology. Accordingly, biomarker epidemiology is undergoing rapid development and expansion and is becoming one of the most promising areas of environmental research. Although expanded applications should be encouraged, many biomarkers are poorly characterized, and attention should be paid to defining their properties in detail.
Biomarkers as tools in human health risk assessment
Authors: Greim H , Csanády G , Filser J G , Kreuzer P , Schwarz L , Wolff T , Werner S 
Published: January 2020

Abstract
Evaluation of occupational or environmental risk due to exposure to chemicals requires sufficient information on the toxic profiles, mechanisms of action, toxicokinetics, dose-response relation, exposure, and the target dose. Usually exposure is estimated by measuring concentrations of the agent in air, food, water, soil, dust, or other media with which a population or an individual is in contact. However, this external exposure is only a rough estimate for the internal exposure (agent dose or its metabolite at the critical target in the organism). Factors of influence are bioavailability of the chemicals, variations in concentrations and routes of exposure, physical activity, and individual variation in rates of metabolism, distribution, and excretion. All these affect the concentration of the toxic agent at the critical target, which is the most precise information for risk assessment. Thus, internal exposure is best measured by determining the concentration of the toxicant or its ultimate metabolite at the critical site in the target organ or by determining adducts with cellular macromolecules such as proteins, amino acids, DNA, or its bases. The latter are easily available in experimental toxicology from animal experiments but only occasionally from humans. For health surveillance such data usually are not available, because they require invasive procedures such as biopsies. Therefore, more accessible body fluids or tissue are used, such as blood, urine, or adipose tissue, or adducts with macromolecules such as albumin or hemoglobin in the blood, DNA adducts in peripheral lymphocytes, or altered DNA bases in urine such as 8-hydroxyguanine. All of these are indicators for exposure, whereas risk can only be estimated if the correlation between their deviations from normal and the dose-response at the critical target is known.
Macromolecular adducts caused by environmental chemicals
Authors: Neumann H G , Albrecht O , van Dorp C , Zwirner-Baier I 
Published: January 2020

Abstract
We describe three biomonitoring studies in which hemoglobin (Hb) adducts were used as biochemical markers to assess indirectly the target dose of genotoxic chemicals. We monitored the exposure to 1,3-butadiene in occupationally exposed workers and in two control groups by analyzing the adducts formed by the reaction of the first activation product, butadiene monoepoxide, with the terminal valine of Hb; we also measured hydrolyzable adducts formed by the reaction of metabolically formed nitroso derivatives with Hb from five selected nitropolycyclic aromatic hydrocarbons (1-nitropyrene; 2-nitrofluorene, 3-nitrofluoranthrene, 6-nitrochrysene, and 9-nitrophenanthrene) in coke oven workers of different job categories and control workers of the same geographical area. We detected hydrolyzable adducts from monocyclic nitroarenes in blood from individuals living in a contaminated area where explosives had been produced and from controls. The contaminants considered were 2,4,6-trinitrotoluene; 2,4- and 2,6-dinitrotoluene; and 1,3-dinitrobenzene. Differences between groups were significant, but interindividual variation was great and back-ground exposures must be considered.
DNA repair and epidemiology of basal cell carcinoma
Authors: Grossman L , Wei Q 
Published: January 2020

Abstract
In a molecular epidemiological study of DNA repair, host reactivation assay was used to measure the DNA repair capacity of cryopreserved lymphocytes from 88 primary basal cell carcinoma (BCC) patients and 135 cancer-free controls. In this study population, reduced repair of ultraviolet radiation-induced DNA damage contributed to the risk of sunlight-induced BCC. A family history of BCC is associated with low DNA repair. Repair of ultraviolet radiation-damaged DNA declines at a rate of approximately 1%/year in noncancerous controls. Reduced DNA repair is more likely seen in young BCC patients, indicating that BCC is a premature aging disease of the skin. The persistence of photochemical damage because of reduced repair results in point mutations in the p53 gene and allelic loss of the nevoid BCC gene located on chromosome 9q. Xeroderma pigmentosum appears to be a valid paradigm for the role of DNA repair in BCC in the general population.
Polymorphisms in drug-metabolizing enzymes as modifiers of cancer risk
Authors: Spurr N K , Gough A C , Chinegwundoh F I , Smith C A 
Published: January 2020

Abstract
The identification of low-penetrance genes, the polymorphisms of which increase an individual's risk of developing cancer, are likely to be extremely important in the general population. In this report we analyzed two genes involved in detoxification. In a number of loci, we identified polymorphic variation correlating with the expression of the gene product. We analyzed two such loci, the cytochrome P-450 gene CYP2D6 and the N-acetyltransferase 2 (NAT2) genes, in patients with bladder and colon cancer, respectively. We observed no statistically significant associations between the control and cancer populations; however, there was a small increase in heterozygote number in bladder cancer.
Do environmental estrogens contribute to the decline in male reproductive health?
Authors: Jensen T K , Toppari J , Keiding N , Skakkebaek N E 
Published: January 2020

Abstract
Several observations suggest that male reproductive health has been declining since World War II in many countries. The incidence of testicular cancer, hypospadias, and cryptorchidism has been increasing and semen quality has been decreasing, and these may have a common etiology. Treatment of several million pregnant women with the synthetic estrogen diethylstilbestrol led to an increase in these conditions among the sons of these women. These abnormalities probably arise during fetal development. The similarity between these effects and the adverse change in male reproductive development and function raised the question of whether the adverse changes are attributable to altered exposures to estrogenic and other endocrine-disrupting agents during fetal development. We speculate that alteration in exposure to estrogen in the past half-century may have caused the changes in male reproductive health.
Improved PCR amplification/Hhal restriction for unambiguous determination of apolipoprotein E alleles
Authors: Appel E , Eisenberg S , Roitelman J 
Published: January 2020

Abstract
We present a modification to the polymerase chain reaction amplification/Hhal restriction isotyping method for human apolipoprotein (apo) E. This method includes a mutagenic forward primer and 5'-end labeling of both primers. These modifications of the original method described by Hixon and Vernier (J Lipid Res 1990;31:545-8) allow sensitive and unambiguous determination of apoE genotypes.
Analytical and clinical performance of improved Abbott IMx CA 125 assay: comparison with Abbott CA 125 RIA
Authors: Thomas C M , Massuger L F , Segers M F , Schijf C P , Doesburg W H , Wobbes T 
Published: January 2020

Abstract
We compared the improved Abbott IMx cancer antigen (CA) 125 assay (cat. no. 7A89) with the Abbott CA 125 RIA. Serum specimens were from healthy perimenopausal women (n = 124) and from patients with benign gynecologic and nongynecologic diseases (n = 124), ovarian carcinoma (n = 104), or other malignancies (n = 193). The IMx assay detected as little as 0.193 kAU/L CA 125 (AU = arbitrary Abbott unit), demonstrated up to 29% overestimation upon serum dilution, low within-assay (2.7-5.6%) and between-assay (4.8-8.2%) CVs, and no high-dose hook effect &lt; or = 46,000 kAU/L nor influence from human anti-mouse antibodies in serum of women injected with OC 125 F(ab')2. Values by IMx were 20% lower than by RIA for healthy perimenopausal women (n = 100; IMx = 0.80 RIA - 2.5 kAU/L), and at least 50% higher for those with benign or malignant ovarian disorders at concentrations &lt; 100 kAU/L. Receiver-operating characteristic (ROC) curve analysis of ovarian neoplasma vs perimenopausal controls indicated a gain of specificity and sensitivity with the improved IMx assay over the RIA, but ROC performance was the same with either assay if patients with benign ovarian disorders were used as controls.
Clinical utility of biochemical analysis of cerebrospinal fluid
Authors: Watson M A , Scott M G 
Published: January 2020

Abstract
In addition to microbial culture, cytology, and immunological studies, physicians rely on the clinical chemistry laboratory for biochemical analysis of patients' cerebrospinal fluid (CSF). However, apart from routine glucose and protein determinations, the clinical value of other CSF analytes is often unclear. Here, we review the literature pertaining to the use of CSF biochemical measurements in managing patients with infectious disease, neoplasia, stroke and trauma, and dementia. Although a small number of studies demonstrate potential usefulness of some markers, we conclude that, without further study, the data are insufficient to support the routine clinical use of most of the analytes examined.
Immunoprecipitation assay for autoantibodies to steroid 21-hydroxylase in autoimmune adrenal diseases
Authors: Colls J , Betterle C , Volpato M , Prentice L , Smith B R , Furmaniak J 
Published: January 2020

Abstract
Adrenal autoantibodies characteristic of autoimmune Addison disease are directed towards steroid 21-hydroxylase (21-OH; EC 1.14.99.10). We describe a new assay to measure 21-OH autoantibodies (21-OH Abs), based on immunoprecipitation by the antibodies of 35S-labeled human 21-OH. Using this immunoprecipitation assay (IPA), we detected 21-OH Abs in 42 of 64 (66%) patients with Addison disease and in 14 of 19 (74%) patients with autoimmune polyendocrine syndromes type I and type II. No 21-OH Abs were detected by the IPA in any patients with Addison disease attributable to tuberculosis (n = 9) or adrenoleukodystrophy (n = 9) or in patients with autoimmune thyroid disease (n = 28), systemic lupus erythematosus (n = 10), myasthenia gravis (n = 10), rheumatoid arthritis (n = 10), or insulin-dependent diabetes mellitus (n = 12). None of the 26 sera from healthy normal blood donors was positive for 21-OH Abs by the assay. We found good agreement between 21-OH Abs measured by IPA and by Western blotting (r = 0.83, n = 123, P &lt; 0.001). The inter- and intraassay CVs for IPA were well &lt; 10% at high, medium, and low concentrations of 21-OH Abs. Overall, our studies indicate that the IPA provides a specific, sensitive, and convenient system for measuring 21-OH Abs.
Direct enzyme-linked immunosorbent assay and a radioimmunoassay for melatonin compared
Authors: Chegini S , Ehrhart-Hofmann B , Kaider A , Waldhauser F 
Published: January 2020

Abstract
A novel commercially available ELISA for direct measurement of melatonin concentration in serum was evaluated and compared with an RIA routinely used in our laboratory. The direct ELISA is technically simpler, requires a smaller sample volume (0.1 mL), and compares well with RIA in terms of stability of the calibration curve and intra- and interassay CVs. Correlation with RIA measurements is, however, suboptimal (y = 0.39x + 56; r = 0.65, P &lt; 0.001; n = 138), which may be due to a serum effect, as evidenced by dilution studies. Furthermore, the detection range of the ELISA does not cover the physiological daytime melatonin concentrations in humans. Adding an extraction and 10-fold concentration step shifted the detection range of the ELISA to include low physiological concentrations as well. Correlation with RIA measurements also improved significantly (y = 0.97x-23; r = 0.95, P &lt; 0.001; n = 105), probably due to removal of the serum effect. Although extraction increases the required sample volume (1.5 mL), work load, and procedure time, this step is necessary for the ELISA to compete successfully with RIA.
Isotope dilution mass spectrometry as a candidate definitive method for determining total glycerides and triglycerides in serum
Authors: Ellerbe P , Sniegoski L T , Welch M J 
Published: January 2020

Abstract
A new isotope dilution mass spectrometric method for total glycerides and triglycerides in human serum is described. Total glycerides are defined as the sum of tri-, di-, and monoglycerides plus free glycerol; triglycerides are defined as the pure triglyceride species. In both determinations, serum samples are supplemented by addition of [13C3]tripalmitin, processed, derivatized, and the abundance ratios of selected ions are determined. Bias is investigated by quantifying the analyte in the same samples under different chromatographic and ionization conditions. The analytes were determined in two human serum pools. The CV for a single measurement ranged from 0.35% to 0.72%, and the relative SEM ranged from 0.10% to 0.34%; there was no significant bias in the measurements. The combination of high precision and absence of significant bias in the results qualify this method for consideration as a Definitive Method as defined by the National Committee for Clinical Laboratory Standards.
Significance of low serum alkaline phosphatase activity in a predominantly adult male population
Authors: Lum G 
Published: January 2020

Abstract
The causes for low serum alkaline phosphatase (ALP) activity (reference range 30-115 U/L) in a large Veterans Medical Center were reviewed. Of 69,864 ALP determinations made over a 4-year period, 130 were low (&lt; 30 U/L, 0.19%), representing 88 individual patients. Of these, 83 (primarily men, 96%) patients' charts were reviewed and classified into two groups, those with and those without conditions previously reported to be associated with decreased serum ALP activity: 47% had conditions associated with low ALP activity, the most frequent being cardiac surgery and cardiopulmonary bypass (26.5%), malnutrition (12.0%), magnesium deficiency (4.8%), hypothyroidism (2.4%), and severe anemia (1.2%); 53% of patients did not have clinical conditions previously associated with low ALP activity. No case of clinically apparent hypophosphatasia, for which low ALP activity is the defining characteristic, was found in this population of veterans. A low serum ALP may be of significance in other patient populations such as children, where it is associated with achondroplasia and cretinism, or in postmenopausal women with osteoporosis taking estrogen replacement therapy. In the predominantly adult male population in this study, low ALP activity was rare; it was seen most frequently in cardiac surgery patients postoperatively, a clinical condition heretofore not commonly associated with low serum ALP activity.
Automated measurement of alpha-amylase isoenzymes with 6(3)-deoxymaltotriose as selective amylase inhibitor
Authors: Uchida R , Tokutake S , Motoyama Y , Hosoi K , Yamaji N 
Published: January 2020

Abstract
We developed an automated method for measurement of alpha-amylase isoenzymes in serum by a single kinetic assay (SKA) and a double kinetic assay (DKA) with 2-chloro-4-nitrophenyl-6(5)-azido-6(5)-deoxy-beta-maltopentaoside as a substrate and 6(3)-deoxymaltotriose (DOG3) as a novel selective amylase inhibitor. DOG3 showed a large difference in inhibitory activity between human pancreatic alpha-amylase (HPA; 86.9% inhibition) and salivary alpha-amylase (32.1% inhibition) at 0.33 mmol/L. Constant inhibition was obtained immediately after addition of DOG3. The inhibitory effect did not change with variation in concentrations of amylase up to approximately 3000 U/L. The results obtained by SKA correlated well with those obtained by three methods: monoclonal antibody (r = 0.988), wheat germ inhibitor (r = 0.989), and DKA (r = 0.995). The within-run and between-run CVs for HPA were 0.63-2.32% on SKA, 0.69-1.81% on DKA. No significant interferences by endogenous serum compounds were observed with the proposed methods.
Age-related reference values for urinary excretion of sialic acid and deoxysialic acid: application to diagnosis of storage disorders of free sialic acid
Authors: Romppanen J , Mononen I 
Published: January 2020

Abstract
We have established by HPLC age-related reference intervals for sialic acid urinary excretion in 364 control individuals to assist in evaluating the clinical significance of the free sialic acid concentration in urine. In addition, an HPLC method for quantitative analysis of free deoxysialic acid was developed, and age-related reference intervals for excretion of this compound in urine were established. In patients with storage disorders of free sialic acid (n = 11) the sialic acid excretion was increased 2- to 35-fold, compared with the mean value of the control subjects in the corresponding age group, and exceeded the interval in each case. The excretion of deoxysialic acid was within the reference interval in all of the patients, indicating that its metabolism was not affected in the disorders. The age-related reference values assist in evaluating the excretion of free sialic acid in the diagnosis of storage disorders of free sialic acid, especially in young children.