bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interference of Plant Peroxidases with Guaiac-based Fecal Occult Blood Tests Is Avoidable
Authors: Sinatra Marc A , St. John D James B , Young Graeme P 
Published: January 2020

Abstract
Peroxidase-rich fruits and vegetables are reputed to interfere with guaiac-based fecal occult blood tests. We added horseradish peroxidase to fecal samples and tested them with Hemoccult®, Hemoccult SENSA®, and hydrated Hemoccult. Positivity rates with Hemoccult and Hemoccult SENSA decreased rapidly as the time between smearing (preparation) and development increased, whereas they remained high with hydrated Hemoccult. For samples with added blood, positivity rates did not decrease with time. When 61 volunteers were tested on a standard restriction and on a challenge diet high in plant peroxidase, no positive results occurred during standard restriction. During the challenge diet, one volunteer was positive with Hemoccult and Hemoccult SENSA when development was delayed 24 h, and no volunteers were positive when it was delayed 48 h and 72 h. However, with hydrated Hemoccult, positives occurred in 13 of 61 volunteers at 24 h, 8 of 61 at 48 h, and 5 of 61 at 72 h. Thus, peroxidase-rich plant foods do not need to be excluded from the diet with Hemoccult and Hemoccult SENSA if development is delayed for at least 48 h after smearing. A delay of this duration will not solve the problem of plant peroxidase interference with hydrated Hemoccult.
Immunoreactivity, Ultrastructural Localization, and Transcript Expression of Prostate-specific Antigen in Human Neuroblastoma Cell Lines
Authors: Mannello Ferdinando , Malatesta Manuela , Luchetti Francesca , Papa Stefano , Battistelli Serafina , Gazzanelli Giancarlo 
Published: January 2020

Abstract
Prostate-specific antigen (PSA) is considered a highly specific biochemical marker of the human prostate gland, and it currently is used for prostate cancer diagnosis and monitoring. Recently, PSA production and secretion were found in nondiseased and diseased cells, tissues, and fluids from women. In this study, we characterized the presence of PSA in two human neuroblastoma cell lines with biochemical, ultrastructural, and molecular approaches. Using reverse transcription-PCR, we identified PSA mRNA, and Western blotting revealed a substantial amount of complexed form of PSA protein, which is localized mainly in free ribosomes. Although the role of PSA in human neuroblastoma cell lines is still unknown, our study supports the hypothesis that this serine protease may be involved in controlling the growth of human brain tumor cells, adding more support to the notion that PSA is a widespread kallikrein-like protease with biological functions much more complex than recently thought.
Presence of Donor- and Recipient-derived DNA in Cell-free Urine Samples of Renal Transplantation Recipients: Urinary DNA Chimerism
Authors: Zhang Jun , Tong Kwok-Lung , Li Philip KT , Chan Albert YW , Yeung Chung-Kwong , Pang Calvin CP , Wong Teresa YH , Lee Kam-Cheong , Lo YM Dennis 
Published: January 2020

AbstractBackground: Previous studies have indicated that microchimerism is present in body tissues, peripheral blood, and plasma of recipients after organ transplantation. We hypothesize that donor-derived DNA may also be present in cell-free urine of renal transplant recipients and that the concentrations of urine DNA may be correlated with graft rejection.Methods: Thirty-one female patients who had renal transplantation were enrolled in the study. In women with male organ donors, the SRY gene on the Y chromosome was used as a marker for donor-derived DNA. Real-time quantitative PCR for the SRY and β-globin genes was carried out on cell-free urinary DNA from these patients. Serial urine samples from a female renal transplant recipient undergoing an acute rejection episode were also collected and analyzed with the β-globin quantitative PCR system.Results: SRY sequences were detected in the urine of 14 of 17 female patients with male organ donors. None of the 14 patients with female organ donors had detectable SRY sequences in urinary DNA. The median fractional concentration of donor-derived DNA was 8.7% (interquartile range, 1.9–26.4%). During the acute rejection episode, urinary concentrations of the β-globin gene were markedly increased, with the concentrations returning rapidly to normal following antirejection treatment.Conclusions: Our results demonstrate that urinary DNA chimerism is present following renal transplantation. The measurement of urinary DNA using quantitative PCR may be useful for the diagnosis and monitoring of graft rejection.
Evaluation of a Rapid Whole Blood ELISA for Quantification of Troponin I in Patients with Acute Chest Pain
Authors: Heeschen Christopher , Goldmann Britta U , Langenbrink Lukas , Matschuck Guido , Hamm Christian W 
Published: January 2020

AbstractBackground: Troponin I (cTnI) provides important prognostic information in patients with chest pain. We wished to evaluate a rapid, whole-blood analyzer for quantitative point-of-care testing.Methods: A quantitative point-of-care test system (Stratus CS®; Dade-Behring) for cTnI with an incorporated centrifuge was evaluated in 412 patients with chest pain less than 12 h.Results: Results were available within 15 min. CVs were 4.5% at 0.1 μg/L, 4.2% at 0.25 μg/L, and 6.5% at 0.82 μg/L. The detection limit was 0.01 μg/L. The 97.5% percentile in a healthy population was 0.08 μg/L. Based on ROC curve analysis, a threshold of 0.15 μg/L was calculated for the detection of acute myocardial infarction (AMI). With it, sensitivity for the detection of patients with AMI (n = 62) was 63% at arrival and 98% after 4 h (Stratus II®, 48% and 85%, respectively; P &lt;0.01). In 42% of patients with unstable angina (n = 121), cTnI was ≥0.08 μg/L (Stratus II, 28%; P &lt;0.01). During 30 days, death or AMI occurred in 25.5% of these cTnI-positive vs 2.9% of cTnI-negative patients (Stratus II, 29.4% vs 5.8%).Conclusion: The Stratus CS provided better analytical performance and comparable or better prognostic information than the Stratus II.
Aminopeptidase Activities in Breast Cancer Tissue
Authors: Martínez José M , Prieto Isabel , Ramírez María J , Cueva Cristobal , Alba Francisco , Ramírez Manuel 
Published: January 2020

Abstract
Background: Endopeptidases such as cathepsins help determine the prognosis of breast cancer (BC). However, little information is available about the role in BC of aminopeptidases (APs), which have been implicated in the metabolism of several local hormonal factors.
Methods: Using aminoacyl-β-naphthylamides as substrates, we measured fluorometrically alanyl-AP, arginyl-AP, cystinyl-AP, glutamyl-AP, aspartyl-AP, and pyroglutamyl-AP activities in their soluble and membrane-bound forms in surgically removed BC tissue from which we separated samples of neoplastic, adjacent tumoral, and unaffected surrounding tissue.
Results: Compared with unaffected tissue, neoplastic tissue had significantly higher activities of soluble alanyl-AP (553.9 ± 82.8 vs 1615.2 ± 183.0 pmol/mg protein; P &lt;0.001), arginyl-AP (372.4 ± 56.6 vs 1027.2 ± 143.5 pmol/mg protein; P &lt;0.001), and cystinyl-AP (74.8 ± 10.0 vs 282.9 ± 37.2 pmol/mg protein; P &lt;0.001), and of membrane-bound arginyl-AP (457.7 ± 97.9 vs 886.6 ± 140.0 pmol/mg protein; P &lt;0.01). However, membrane-bound aspartyl-AP activity was significantly lower in neoplastic tissue (17.3 ± 1.4 vs 9.2 ± 1.2 pmol/mg protein; P &lt;0.05) and pyroglutamyl-AP activity was significantly lower in neoplastic and adjacent tissues (12.8 ± 0.9 vs 7.0 ± 1.2 and 8.0 ± 1.3 pmol/mg protein; P &lt;0.001 for both comparisons).
Conclusions: The present results document changes in AP activities in BC tissue. These changes may reflect the functional status of the AP substrates, which can be selectively activated or inhibited locally in the affected tissue as a result of specific conditions brought about by the tumor.
Serum Sialic Acid in a Random Sample of the General Population
Authors: Pönniö Maritta , Alho Hannu , Nikkari Seppo T , Olsson Ulf , Rydberg Ulf , Sillanaukee Pekka 
Published: January 2020

AbstractBackground: The serum sialic acid (SA) concentration has been reported to be a potentially useful but nonspecific disease marker. We wanted to study which factors influence SA concentration in a well-characterized healthy population.Methods: SA was determined in 97 women and 96 men with a colorimetric Warren method.Results: The mean ± SD concentrations of SA were 634 ± 109 (95% confidence interval, 612–656) and 630 ± 106 (95% confidence interval, 608–651) mg/L for women and men, respectively. The serum SA showed a significant positive association with body mass index and with systolic and diastolic blood pressure among both women and men. SA also correlated significantly with the use of contraceptive pills and age among women and with smoking among men.Conclusions: Our study suggests that SA does not increase with age in men but appears to increase with female menopause. The strong positive association with blood pressure may explain why SA predicts cardiovascular mortality.
Molecular Diagnostics on Microfabricated Electrophoretic Devices: From Slab Gel- to Capillary- to Microchip-based Assays for T- and B-Cell Lymphoproliferative Disorders
Authors: Munro Nicole J , Snow Karen , Kant Jeffrey A , Landers James P 
Published: January 2020

Abstract
Background: Current methods for molecular-based diagnosis of disease rely heavily on modern molecular biology techniques for interrogating the genome for aberrant DNA sequences. These techniques typically include amplification of the target DNA sequences followed by separation of the amplified fragments by slab gel electrophoresis. As a result of the labor-intensive, time-consuming nature of slab gel electrophoresis, alternative electrophoretic formats have been developed in the form of capillary electrophoresis and, more recently, multichannel microchip electrophoresis.
Methods: Capillary electrophoresis was explored as an alternative to slab gel electrophoresis for the analysis of PCR-amplified products indicative of T- and B-cell malignancies as a means of defining the elements for silica microchip-based diagnosis. Capillary-based separations were replicated on electrophoretic microchips.
Results: The microchip-based electrophoretic separation effectively resolved PCR-amplified fragments from the variable region of the T-cell receptor-γ gene (150–250 bp range) and the immunoglobulin heavy chain gene (80–140 bp range), yielding diagnostically relevant information regarding the presence of clonal DNA populations. Although hydroxyethylcellulose provided adequate separation power, the need for a coated microchannel for effective resolution necessitated additional preparative steps. In addition, preliminary data are shown indicating that polyvinylpyrrolidone may provide an adequate matrix without the need for microchannel coating.
Conclusions: Separation of B- and T-cell gene rearrangement PCR products on microchips provides diagnostic information in dramatically reduced time (160 s vs 2.5 h) with no loss of diagnostic capacity when compared with current methodologies. As illustrated, this technology and methodology holds great potential for extrapolation to the abundance of similar molecular biology-based techniques.
Activated Protein C Resistance: Automated Detection of the Factor V Leiden Mutation by Mismatch Hybridization
Authors: Klingler Karl R , Junold Thomas , Wielckens Klaus 
Published: January 2020

AbstractBackground: A single point mutation in the factor V gene has been demonstrated to be the cause of factor Va resistance to proteolytic cleavage by activated protein C. Knowledge of the patient’s genetic disposition is of great importance in situations such as pregnancy, surgery, use of oral contraceptives, and immobilization.Methods: We have developed a rapid, automated test for the detection of the factor V mutation that makes use of differences in thermal stability between perfect-match and non-perfect-match hybrids. A DNA fragment spanning the mutation is amplified with a biotin-labeled primer. Ruthenium-labeled oligonucleotides, perfectly matching either the biotinylated wild-type strand or the biotinylated mutation strand, are added. Heating to 95 °C and subsequent cooling lead to the formation of double-stranded DNA. Under the conditions chosen, ruthenium-labeled oligonucleotides form stable, double-stranded DNA with the biotinylated strand only if both strands perfectly match each other. The ruthenium signal is measured on a modified Elecsys 1010 system (Roche Diagnostics).Results: The ratio between the signals obtained with perfectly matching and non-perfectly matching oligonucleotides reflects the genetic status. Analyzed samples can be divided into three nonoverlapping groups based on these ratios. We confirmed the reliability of the method by analyzing several samples of known genetic status; the results were identical in every single instance.Conclusions: The test discriminates unambiguously between the heterozygous and the homozygous states. Because of its low costs and easy handling, the assay is suitable for use in routine laboratories of clinical chemistry.
New Electrochemiluminescent Immunoassay for the Determination of CYFRA 21-1: Analytical Evaluation and Clinical Diagnostic Performance in Urine Samples of Patients with Bladder Cancer
Authors: Sánchez-Carbayo Marta , Espasa Antonia , Chinchilla Virtudes , Herrero Enrique , Megías Julián , Mira Antonio , Soria Federico 
Published: January 2020

Abstract
Background: A new electrochemiluminescent immunoassay (ECLIA) has been developed for the determination of cytokeratin 19 (CYFRA 21-1) in the Elecsys 2010 immunoassay system. Urinary CYFRA 21-1 might have a role in the diagnosis of bladder cancer.
Methods: We performed an analytical evaluation of the CYFRA 21-1 ECLIA for serum and urine samples. The clinical value of urinary CYFRA 21-1 for the detection of bladder cancer was evaluated through its measurement in 226 urine samples from symptomatic and asymptomatic controls.
Results: At concentrations of 2–30 μg/L, within-assay imprecision (CV) was below 2.1% for sera and 3.3% for urines, with interassay CVs below 3.3% for sera and 4.9% for urines. The day-to-day CV was &lt;20% at concentrations &gt;0.2 μg/L (functional sensitivity). Measurement of diluted samples showed that the assay estimated CYFRA 21-1 between 98% and 103% for sera and 98% and 105% for urines. Recovery of added CYFRA 21-1 was 99–105% for sera and 96–115% for urines. We separately compared serum and urine CYFRA 21-1 ECLIA results with those obtained with an IRMA (CIS bio international). Regression analysis for sera was: CYFRA 21-1 (ECLIA) = 0.520 + 1.018 CYFRA 21-1 (IRMA); [95% confidence interval (CI) (y-intercept), −0.260 to 1.309]; 95% CI (slope), 0.978–1.060; n = 100; Sy|x = 3.242; r2 = 0.987. For urine samples it was: CYFRA 21-1 (ECLIA) = 0.716 + 0.966 CYFRA 21-1 (IRMA); 95% CI (y-intercept), 0.009–1.422; 95% CI (slope), 0.956–0.976; n = 100; Sy|x = 4.136; r2 = 0.986. In urine samples voided by patients with and without bladder cancer, the best ROC analysis discrimination provided 81.0% (95% CI, 72.7–87.7%) sensitivity and 97.2% (95% CI, 90.2–99.6%) specificity at a threshold value of 5.7 μg/L.
Conclusions: Our initial evaluation showed reliable analytical performance for urinary CYFRA 21-1, which might assist urologists in the detection of bladder cancer as a noninvasive adjunct to cystoscopy.
The Combination of Human Glandular Kallikrein and Free Prostate-specific Antigen (PSA) Enhances Discrimination Between Prostate Cancer and Benign Prostatic Hyperplasia in Patients with Moderately Increased Total PSA
Authors: Magklara Angeliki , Scorilas Andreas , Catalona William J , Diamandis Eleftherios P 
Published: January 2020

AbstractBackground: Prostate-specific antigen (PSA) is the most reliable tumor marker available and is widely used for the diagnosis and management of prostate cancer. Unfortunately, PSA cannot distinguish efficiently between benign and malignant disease of the prostate, especially within the range of 4–10 μg/L. Among the refinements developed to enhance PSA specificity is the free/total PSA ratio, which is useful in discriminating between the two diseases within the diagnostic “gray zone”. Recent data indicate that human glandular kallikrein (hK2), a protein with high homology to PSA, may be an additional serum marker for the diagnosis and monitoring of prostate cancer.Methods: We analyzed 206 serum samples (all before treatment was initiated) from men with histologically confirmed benign prostatic hyperplasia (n = 100) or prostatic carcinoma (n = 106) with total PSA in the range of 2.5–10 μg/L. Total and free PSA and hK2 were measured with noncompetitive immunological procedures. Statistical analysis was performed to investigate the potential utility of the various markers or their combinations in discriminating between benign prostatic hyperplasia and prostatic carcinoma.Results: hK2 concentrations were not statistically different between the two groups of patients. There was a strong positive correlation between hK2 and free PSA in the whole patient population. hK2/free PSA ratio (area under the curve = 0.69) was stronger predictor of prostate cancer than the free/total PSA ratio (area under the curve = 0.64). At 95% specificity, the hK2/free PSA ratio identified 30% of patients with total PSA between 2.5–10 μg/L who had cancer. At 95% specificity, the hK2/free PSA ratio identified 25% of patients with total PSA between 2.5 and 4.5 μg/L who had cancer.Conclusions: Our data suggest that hK2 in combination with free and total PSA can enhance the biochemical detection of prostate cancer in patients with moderately increased total PSA concentrations. More specifically, the hK2/free PSA ratio appears to be valuable in identifying a subset of patients with total PSA between 2.5 and 4.5 μg/L who have high probability of cancer and who should be considered for biopsy.
RNA Expression of Cardiac Troponin T Isoforms in Diseased Human Skeletal Muscle
Authors: Ricchiuti Vincent , Apple Fred S 
Published: January 2020

AbstractBackground: The expression of multiple cardiac troponin T (cTnT) isoforms has been demonstrated in diseased human skeletal muscle. However, cardiac troponin I (cTnI) expression has been described only in heart muscle. The goal of this study was to determine whether mRNA for cTnT, slow skeletal troponin T (sTnT), or cTnI was expressed in skeletal muscle biopsies obtained from patients with end-stage renal disease (ESRD) and Duchenne muscular dystrophy (DMD).Methods: Total mRNA was extracted from healthy human heart (n = 4), healthy human skeletal muscle (n = 5), and skeletal muscle from patients with ESRD (n = 7) and DMD (n = 5). Total RNA (1 μg) was reverse-transcribed using Moloney murine leukemia virus reverse transcriptase. The reverse-transcribed cDNAs were amplified by PCR using oligonucleotide primers specific for cTnT, sTnT, and cTnI sequences (GenBank accession numbers X74819, m19308, and X54163, respectively).Results: In all heart specimens, a 150-bp cTnT amplicon was detected. Skeletal muscle from four of seven patients with ESRD and two of five patients with DMD showed expression of a 150-bp amplicon. Using DNA sequencing and a comparison program, the 150-bp amplicons found in heart and diseased skeletal muscle specimens were 100% identical and specific to the cTnT mRNA sequence. No cTnT mRNA expression was found in healthy skeletal muscle. No evidence of sTnT mRNA was found in heart muscle. A 200-bp sTnT amplicon specific to a human sTnT sequence was detected in all skeletal muscle specimens. A 250-bp cTnI amplicon specific to the cTnI sequence was detected in all heart specimens. However, no cTnI mRNA expression was found in healthy or diseased skeletal muscle specimens. cTnT mRNA expression in both heart and diseased skeletal muscles corresponded with cTnT isoform expression, respectively, as determined by Western blot analysis.Conclusion: Our findings demonstrate cTnT mRNA expression, but no cTnI mRNA expression, by reverse transcription-PCR in diseased human skeletal muscle that expresses cTnT isoforms.
New Method for Determining Cystine in Leukocytes and Fibroblasts
Authors: de Graaf-Hess Adriana , Trijbels Frans , Blom Henk 
Published: January 2020

AbstractBackground: Cystinosis is a rare inborn error of cystine transport, leading to accumulation of cystine in the lysosomes. To diagnose cystinosis and monitor treatment with cysteamine, adequate measurements of cystine concentrations in leukocytes and cultured fibroblasts are required.Methods: Cells were sonicated in the presence of excess N-ethylmaleimide to prevent oxidation of cysteine to cystine and disulfide exchange reactions of cystine with available sulfhydryl moieties. Cystine was measured as cysteine after reduction with sodium borohydride and derivatization with monobromobimane, followed by separation with automated HPLC and fluorescence detection.Results: The assay was linear to 200 μmol/L cysteine. Within-run and day-to-day (total) imprecision (CV) was &lt;5%, and the detection limit was 0.3 μmol/L. Added cysteine, up to 200 μmol/L, was completely removed, and recovery of added cystine was 69–86%. Cystine was stable for at least 2 months in leukocytes frozen in liquid nitrogen and stored at −80 °CConclusions: Oxidation of cysteine to cystine and disulfide exchange reactions of cystine with sulfhydryl moieties are prevented by N-ethylmaleimide. The detection limit for the determination of cystine is adequate to measure cystine in leukocytes and cultured fibroblasts for diagnosis of cystinosis and monitoring treatment with cysteamine.
Evaluation of Filter Paper Blood Lead Methods: Results of a Pilot Proficiency Testing Program
Authors: Stanton Noel V , Maney Jane M , Jones Robert 
Published: January 2020

Abstract
Background: Lead testing on dried filter paper (FP) blood spots is used routinely by some laboratories for lead poisoning screening. Proficiency testing (PT) as required under CLIA ‘88 laboratory regulations has not been available for these methods.
Methods: We describe a suitable PT scheme and evaluate FP laboratory performance based on program results. Monthly testing events consisting of five FP specimens were provided to six participating laboratories. Results were evaluated against target values determined by referee laboratories.
Results: Preliminary FP laboratory results showed poor agreement with specimen target values, exhibiting a mean absolute bias of 0.29 μmol/L (5.9 μg/dL). Five of six participating laboratories demonstrated significant improvement in later testing events, with bias decreasing to 0.12 μmol/L (2.5 μg/dL). Performance varied widely between the participating laboratories and appeared to be method dependent. When evaluated using CLIA blood lead acceptability criteria, the proportion of acceptable individual specimen results (n = 35) ranged from 54% to 100%. On a testing event basis (n = 7), the proportion of acceptable events ranged from 29% to 100%.
Conclusions: A suitable FP PT program now exists to capably assist and monitor FP laboratories. Based on overt PT results, properly utilized FP testing methods can accurately measure blood lead concentration.