bluuebunny/crossref_metadata_2025_split huggingface dataset:
Total Protein Determination in Urine: Elimination of a Differential Response between the Coomassie Blue and Pyrogallol Red Protein Dye-binding Assays
Authors: Marshall Thomas , Williams Katherine M 
Published: January 2020

AbstractBackground: The total protein content of urine is a good index of renal function, but its determination is unreliable. Protein dye-binding assays are simple, but they characteristically lack a uniform response to different proteins.Methods: We investigated a differential response of the Sigma Microprotein Coomassie Brilliant Blue (CBB) and Pyrogallol Red-molybdate (PRM) protein dye-binding assays to urine, using human albumin, albumin/globulin, or urinary protein as calibrator.Results: The urine protein values (n = 60) obtained with the CBB assay were 110–13 500 mg/L (mean, 2390 mg/L) compared with 160–18 300 mg/L (mean, 3470 mg/L) obtained with the PRM assay (CBB:PRM protein concentration ratio, 0.46–0.88, mean, 0.69 ± 0.10). The differential response was highly reproducible as indicated by Sigma urine control Level 1 (within-day CBB:PRM ratio, 0.68 ± 0.02; between-day CBB:PRM ratio, 0.67 ± 0.04) and Sigma urine control Level 2 (within-day CBB:PRM ratio, 0.60 ± 0.01; between-day CBB:PRM ratio, 0.59 ± 0.02). The use of urinary protein as a calibrator (rather than human albumin) greatly improved the agreement between the assays when applied to urine (yCBB = 0.972xPRM − 16 vs yCBB = 0.685xPRM + 17). In studies using urine controls, this calibrator also improved agreement between the CBB, PRM, trichloroacetic acid (TCA), and benzethonium chloride protein methods and, to a lesser extent, agreement with the TCA-Ponceau S method.Conclusion: The use of a urinary protein calibrator improves the agreement between different methods used to determine total protein in urine.
Development of a Kinetic Assay for Band 5b Tartrate-resistant Acid Phosphatase Activity in Serum
Authors: Nakanishi Mamoru , Yoh Kousei , Miura Toshihide , Ohasi Tatsuya , Rai Shiba Kumar , Uchida Kagehiro 
Published: January 2020

Abstract
Background: Band 5 tartrate-resistant acid phosphatase (TrACP; EC 3.1.3.2) consists of two isoenzymes, bands 5a and 5b, of which band 5b TrACP is considered to be derived from bone. However, no kinetic method for the specific measurement of band 5b TrACP in serum is available. Our aim was to develop a kinetic assay method for the specific measurement of band 5b TrACP in serum.
Methods: Band 5b TrACP was measured kinetically in serum as tartrate-resistant fluoride-sensitive heparin-resistant ACP with 2,6-dichloro-4-acetylphenyl phosphate as substrate at pH 6.6.
Results: Heparin inhibited band 5a TrACP but had no effect on band 5b TrACP in serum or in bone extract. The presence of EDTA or ascorbic acid had no effect, but dithiothreitol inhibited enzyme activity. The within-run (n = 20) and between-run (n = 20) CVs of band 5b TrACP activity were 3.3–5.8% and 5.0–7.3%, respectively. The mean ± SD values of band 5b TrACP activity in males (n = 25) and females (n = 57) 20–29 years of age by this method were 8.0 ± 2.2 U/L and 6.4 ± 1.8 U/L, respectively. The band 5b TrACP value was significantly higher in females &gt;50 years of age compared with the younger subjects (20–29 years). The highest band 5b TrACP values were among children younger than 15 years.
Conclusions: This kinetic assay is a simple and specific method for the measurement of band 5b TrACP in serum samples and is useful in the evaluation of bone turnover activity.
Analysis of Free Prostate-specific Antigen (PSA) after Chemical Release from the Complex with α1-Antichymotrypsin (PSA-ACT)
Authors: Peter Jochen , Unverzagt Carlo , Hoesel Wolfgang 
Published: January 2020

AbstractBackground: Prostate-specific antigen (PSA), a marker for prostate cancer (CaP), forms a covalent complex with α1-antichymotrypsin (ACT) in human blood. Structural analysis of the PSA-ACT complex is difficult, and complexation may be a reason for biased immunological assays when compared with the analysis of free PSA. We developed a method to cleave the PSA-ACT complex chemically. The liberated PSA was thus available for analysis as free PSA (F-PSA).Methods: PSA was released from the PSA-ACT complex by cleaving the interprotein ester bond with ethanolamine under alkaline conditions. The release was followed by reversed-phase HPLC and an immunoassay for F-PSA. Released PSA obtained from human blood was further immunopurified and analyzed by matrix-assisted laser desorption-induced time of flight (MALDI-TOF) mass spectrometry.Results: In vitro-prepared PSA-ACT complex was completely cleaved by treatment with nucleophilic compounds such as ethanolamine at pH 9–10. The released PSA was stable under these conditions and could be measured by reversed-phase HPLC as well as the ENZYMUN® immunoassay for F-PSA. When plasma from a CaP patient [containing 190 μg/L F-PSA and 1890 μg/L total PSA (T-PSA)] was treated under similar conditions, a concentration of ∼1600 μg/L F-PSA was measured at the end of the incubation, indicating that the PSA-ACT complex was completely cleaved. Two benign prostatic hyperplasia and CaP sera panels (12 and 13 sera, respectively) containing 4–45 μg/L T-PSA were similarly treated. The concentrations of F-PSA measured after incubation were, on average, 85% of the T-PSA values of the untreated sera. Finally, the PSA released from the complex of the CaP plasma was isolated by immunosorption, analyzed by MALDI-TOF mass spectrometry, and compared to PSA obtained from semen. The intact PSA as well as the peptides observed after digestion with endoproteinase Lys C did not reveal any structural difference between the PSA from these two sources.Conclusions: PSA complexed to ACT in plasma of a CaP patient seems to be structurally very similar to the PSA reference material from semen. The release of PSA from the PSA-ACT complex allows F-PSA and T-PSA to be measured by the same immunological assay, thus eliminating any possible bias between two different assays.
Analytical and Clinical Performance of a Detergent-based Homogeneous LDL-Cholesterol Assay: A Multicenter Evaluation
Authors: Nauck Matthias , Graziani Maria Stella , Bruton Deborah , Cobbaert Christa , Cole Thomas G , Lefevre Fabrice , Riesen Walter , Bachorik Paul S , Rifai Nader 
Published: January 2020

Abstract
Background: LDL-cholesterol (LDL-C) concentrations currently are determined in most clinical laboratories using the Friedewald calculation. This approach has several limitations and may not always meet the current total error recommendation in LDL-C measurement of ≤12% established by the National Cholesterol Education Program.
Methods: In a multicenter study, we evaluated the analytical and clinical performance of a homogeneous LDL-C assay (LDL-CRoche; Roche Diagnostics, Indianapolis, IN) in a comparison with a β-quantification method.
Results: This direct assay correlated highly with a β-quantification method (r = 0.968; y = 1.037x − 95.8 mg/L; n = 355; 95% confidence intervals, 1.011–1.063 for the slope and −129.5 to 62.0 mg/L for the y-intercept) and met the current total error requirement. The assay was not affected significantly by concentrations of hemoglobin up to 6000 mg/L or bilirubin up to 500 mg/L. However, a negative bias of 10% was seen when triglyceride concentrations exceeded 10 000 mg/L. At the medical decision cut-point range, the LDL-CRoche assay showed positive predictive values of 91–100% and negative predictive values of 80–99%. Furthermore, the clinical utility of the assay seemed unaffected in samples obtained postprandially.
Conclusions: The homogeneous LDL-CRoche assay meets the currently established analytical performance goals and may be useful for the diagnosis and management of hyperlipidemic patients.
Oral Testosterone Administration Detected by Testosterone Glucuronidation Measured in Blood Spots Dried on Filter Paper
Authors: Peng Shi-Hua , Segura Jordi , Farré Magí , de la Torre Xavier 
Published: January 2020

Abstract
Background: Blood sampling is not a common practice for sports drug testing. Our aim was to investigate whether dried blood spots on filter paper could be an alternative to plasma samples for monitoring steroid profiles in dope testing.
Methods: We collected dried blood spots and plasma from six healthy Caucasian subjects after an oral 120-mg dose of testosterone undecanoate (TU). Nonconjugated testosterone, testosterone glucuronide (TG), androsterone glucuronide (AG), and etiocholanolone glucuronide (EtG) were measured by gas chromatography–mass spectrometry in both matrices. 17α-Hydroxyprogesterone (17αOHP) and luteinizing hormone (LH) also were measured in the plasma samples. For comparison, similar measurements were done on samples obtained from the same subjects given 25 mg of testosterone propionate (TP) plus 110 mg of testosterone enanthate (TE) intramuscularly after a wash-out period.
Results: After oral TU intake, TG, AG, and EtG increased sharply, whereas nonconjugated testosterone did not change significantly. Results on dried blood spots correlated well with those on plasma. The TG/testosterone ratio in blood or plasma was verified to be a sensitive and specific marker (significantly increased for up to 8 h after intake; P &lt;0.05) for oral TU intake but not for intramuscular administration of TP plus TE. Little suppression of plasma LH and 17αOHP was observed after a single oral dose of TU. One subject did not show a significant increase of blood TG after oral TU intake.
Conclusions: The measurement of glucuronide conjugates in blood and plasma samples is relevant for sports drug testing when analyzing the steroid profile. Dried blood spots collected on filter paper are a suitable alternative to plasma for detecting testosterone abuse.
Remnant-like Particle-Cholesterol Concentrations in Patients with Type 2 Diabetes Mellitus and End-Stage Renal Disease
Authors: Hirany Shaina , O’Byrne Dawn , Devaraj Sridevi , Jialal Ishwarlal 
Published: January 2020

AbstractBackground: Lipid abnormalities contribute significantly to the increased risk of cardiovascular disease in diabetic and end-stage renal disease (ESRD) patients. Accumulating evidence supports a proatherogenic role for remnant lipoproteins. Thus, the aim of the present study was to compare remnant-like particle-cholesterol (RLP-C) in type 2 diabetic and ESRD patients with age- and gender-matched controls.Methods: Using an immunoaffinity assay, we measured RLP-C concentrations in 48 type 2 diabetic patients with (n = 24) and without (n = 24) macrovascular complications, and 24 age- and gender-matched controls, as well as in 38 ESRD patients on hemodialysis (n = 19) and peritoneal dialysis (n = 19), and 19 age- and gender-matched controls.Results: RLP-C correlated significantly with plasma triglycerides (TGs; r = 0.8). When compared with controls, RLP-C concentrations were significantly higher in type 2 diabetic patients with and without macrovascular complications (median, 0.22 and 0.17 mmol/L vs 0.14 mmol/L; P &lt;0.0002 and &lt;0.01, respectively); diabetic patients with macrovascular complications also had significantly higher RLP-C than diabetic patients without macrovascular complications (P &lt;0.05). However, when RLP-C/TG ratios were computed, only diabetic patients with macrovascular complications showed significantly higher RLP-C/TG ratios compared with controls (P &lt;0.05). Regarding ESRD, RLP-C concentrations were significantly increased in patients on both hemodialysis and peritoneal dialysis compared with controls (median, 0.23 and 0.21 mmol/L vs 0.13 mmol/L; P &lt;0.0001). Whereas RLP-C was increased in ESRD patients on hemodialysis with TGs &lt;2.26 mmol/L compared with controls, RLP-C/TG ratios were not significantly increased in these patients.Conclusions: Type 2 diabetic patients with macrovascular disease demonstrated increased RLP-C and RLP-C/TG ratios, whereas ESRD patients showed only increased RLP-C concentrations.
Influence of Glomerular Filtration Rate on Non-(1-84) Parathyroid Hormone (PTH) Detected by Intact PTH Assays
Authors: Brossard Jean-Hugues , Lepage Raymond , Cardinal Héloïse , Roy Louise , Rousseau Louise , Dorais Claude , D’Amour Pierre 
Published: January 2020

AbstractBackground: Commercial intact parathyroid hormone (I-PTH) assays detect molecular form(s) of human PTH, non-(1-84) PTH, different from the 84-amino acid native molecule. These molecular form(s) accumulate in hemodialyzed patients. We investigated the importance of non-(1-84) PTH in the interpretation of the increased I-PTH in progressive renal failure.Methods: Five groups were studied: 26 healthy individuals, 12 hemodialyzed patients, and 31 patients with progressive renal failure subdivided according to their glomerular filtration rate (GFR) into 11 with a GFR between 60 and 100 mL · min−1 · 1.73 m−2, 12 with a GFR between 30 and 60 mL · min−1 · 1.73 m−2, and 8 with a GFR between 5 and 30 mL · min−1 · 1.73 m−2. We evaluated indicators of calcium and phosphorus metabolism and creatinine clearance (CrCl) in the progressive renal failure groups, and the HPLC profile of I-PTH and C-terminal PTH in all groups.Results: Only patients with a GFR &lt;30 mL · min−1 · 1.73 m−2 and hemodialyzed patients had decreased Ca2+ and 1,25-dihydroxyvitamin D, and increased phosphate. In patients with progressive renal failure, I-PTH was related to Ca2+ (r = −0.66; P &lt;0.0001), CrCl (r = −0.61; P &lt;0.001), 1,25-dihydroxyvitamin D (r = −0.40; P &lt;0.05), and 25-hydroxyvitamin D (r = −0.49; P &lt;0.01) by simple linear regression. The importance of non-(1-84) PTH in the composition of I-PTH increased with each GFR decrease, being 21% in healthy individuals, 32% in progressive renal failure patients with a GFR &lt;30 mL · min−1 · 1.73 m−2, and 50% in hemodialyzed patients, with PTH(1-84) making up the difference.Conclusions: As I-PTH increases progressively with GFR decrease, part of the increase is associated with the accumulation of non-(1-84) PTH, particularly when the GFR is &lt;30 mL · min−1 · 1.73 m−2. Concentrations of I-PTH 1.6-fold higher than in healthy individuals are necessary in hemodialyzed patients to achieve PTH(1-84) concentrations similar to those in the absence of renal failure.
Modular Robotic Workcell for Coagulation Analysis
Authors: Graves Sean , Holman Bill , Felder Robin A 
Published: January 2020

Abstract
Background: Total laboratory automation (TLA) has been shown to increase laboratory efficiency and quality. However, modular automation is smaller, requires less initial capital, and requires less planning than TLA. We engineered and performed clinical trials on a modular robotic preanalytical workcell for coagulation analysis.
Methods: Timing studies were used to quantify the efficiency of the manual processes and to identify areas in the processing of coagulation specimens where bottlenecks and long waiting periods were encountered. We then designed our modular robotic system to eliminate these bottlenecks. Our robotic modular workcell was engineered to allow a choice of specimen introduction manually, by conveyor, or by mobile robot. Additional timing studies were performed during clinical trials of the robotic system.
Results: Prior to automation, the time required for preanalytical processing time was 18–107 min; after automation, it was 45–50 min. Additional improvements in workcell efficiency could be realized when high quality, prelabeled specimens were introduced into the system.
Conclusion: Compared with manual methods, modular automation provides more predictable variation in specimen processing.
Detection of the Finnish-Type Congenital Nephrotic Syndrome by Restriction Fragment Length Polymorphism and Dual-Color Oligonucleotide Ligation Assays
Authors: Romppanen Eeva-Liisa , Mononen Ilkka 
Published: January 2020

Abstract
Background: Congenital nephrotic syndrome of Finnish type (NPHS1) is an autosomal recessive disorder characterized by severe proteinuria of intrauterine onset. Ninety-four percent of the Finnish NPHS1 chromosomes have been reported to carry either a 2-bp deletion in exon 2 (FinMajor) or a nonsense mutation in exon 26 (FinMinor) of the NPHS1 gene. The high prevalence of only two mutations in the Finnish population enables the use of molecular techniques in the diagnosis of NPHS1 and for carrier screening.
Methods and Results: We describe two different molecular methods for the detection of the NPHS1 mutations: a PCR-restriction fragment length polymorphism (PCR-RFLP) and a dual-color oligonucleotide ligation assay (OLA). The dual-color OLA, which enables simultaneous detection of the NPHS1 FinMajor and FinMinor mutations, can be used for rapid analysis of large sets of samples. The analysis of 2004 Finnish blood samples revealed 34 carriers of the FinMajor mutation and 1 carrier of the FinMinor mutation, indicating a carrier frequency of 1:59 (95% confidence interval, 1:89–1:44) for the NPHS1 FinMajor mutation and 1:2004 (95% confidence interval, 0 to 1:677) for the NPHS1 FinMinor mutation, respectively.
Conclusion: PCR-RFLP and dual-color OLA are suitable for molecular diagnosis and carrier screening of the major mutations that cause NPHS1.
Circulating Immunoreactive proANP(1-30) and proANP(31-67) in Sedentary Subjects and Athletes
Authors: De Palo Elio F , Woloszczuk Wolfgang , Meneghetti Martina , De Palo Carlo B , Nielsen Henning B , Secher Niels H 
Published: January 2020

Abstract
Background: Atrial natriuretic peptide (ANP) is synthesized and stored in myocytes as prohormone(1-126), which upon release is cleaved into proANP(1-98) and α-ANP(99-126). In addition, cleavage of proANP(1-98) produces proANP(1-30), proANP(31-67), and proANP(79-98) fragments. ProANP(1-30) and proANP(31-67) have roles in fluid and electrolyte homeostasis. The aim of the present study was to develop a plasma assay for proANP(1-30) and proANP(31-67) and to compare results in trained athletes and sedentary subjects.
Methods: Two competitive enzyme immunoassays were established with affinity-purified sheep antiserum against synthetic ANP fragments. The immunoreactivity (ir) of proANP(1-30) and proANP(31-67) was measured in 10-μL plasma samples without extraction in a microwell-based assay. Plasma concentrations in sedentary male subjects (n = 22) and male endurance athletes (n = 14) were examined.
Results: In the assay for ir-proANP(1-30) and ir-proANP(31-67), the concentrations at 95% B/B0 were 4.7 and 14.2 pmol/L, respectively. Within-run CVs were 4–6% and 5–6%, and between-run CVs were 9% for both assays. Both assays were linear on dilution (y = 0.9945x − 0.7291 and y = 1.0001x − 3.428), and the recoveries were 102–112% and 102–106%, respectively. In the sedentary and athletic groups, the ir-proANP(1-30) concentrations were similar: 318 ± 38 pmol/L and 312 ± 25 pmol/L (mean ± SE), respectively, whereas the ir-proANP(31-67) was higher in the rowers (713 ± 81 pmol/L) than in the sedentary subjects (387 ± 71 pmol/L; P &lt;0.005).
Conclusions: The proANP fragment assays are precise (CV &lt;10%) and exhibit nearly quantitative recovery (102–112%). Only ir-proANP(31-67) responds to physical training.
Description of a Computer Program to Assess Cancer Antigen 15.3, Carcinoembryonic Antigen, and Tissue Polypeptide Antigen Information during Monitoring of Metastatic Breast Cancer
Authors: Sölétormos György , Schiøler Vibeke 
Published: January 2020

Abstract
It is time-consuming to process and compare the clinical and marker information registered during monitoring of breast cancer patients. To facilitate the assessment, we developed a computer program for interpreting consecutive measurements. The intraindividual biological variation, the analytical precision profile, the cutoff limit, and the detection limit for each marker are entered and stored in the program. The assessment procedure for marker signals considers the analytical and biological variation of the applied markers. The software package contains a database that can store the interpretation of the measurements as evaluation codes together with patient demographics, information about treatment type, dates for treatment periods, control periods, and evaluation codes for clinical activity of disease. The consecutive concentrations for a patient are imported temporarily into the program from outside sources and presented graphically. Marker concentrations to be compared are selected with the computer mouse and the significance of the difference is calculated by the program. The program has an option for calculating the lead time of marker signals vs clinical information. The program facilitates the monitoring of individual breast cancer patients with tumor marker measurements. It may also be implemented in trials investigating the utility of potential new markers in breast cancer as well as in other malignancies.
Space Flight Is Associated with Rapid Decreases of Undercarboxylated Osteocalcin and Increases of Markers of Bone Resorption without Changes in Their Circadian Variation: Observations in Two Cosmonauts
Authors: Caillot-Augusseau Anne , Vico Laurence , Heer Martina , Voroviev Dimitri , Souberbielle Jean-Claude , Zitterman Armin , Alexandre Christian , Lafage-Proust Marie-Hélène 
Published: January 2020

AbstractBackground: Microgravity induces bone loss by mechanism(s) that remain largely unknown.Methods: We measured biochemical markers related to bone remodeling in two cosmonauts before, during, and after 21- and 180-day space flights, respectively.Results: During both flights, type I procollagen propeptide and bone alkaline phosphatase decreased as early as 8 days after launch. Undercarboxylated osteocalcin percentage increased early and remained high during both flights. Vitamin K supplementation restored carboxylation of osteocalcin during the long-term flight. Urinary and serum C-telopeptide of type I collagen (CTX) increased as early as day 8 of the flights; the increase was greater in serum than in urine. Pyridinoline, free deoxypyridinoline, and N-telopeptide increased less than CTX during the short-term space flight. The circadian rhythm of bone resorption assessed by urine CTX and free deoxypyridinoline was not altered by microgravity.Conclusion: Vitamin K metabolism or action and bone remodeling may be altered in cosmonauts.
Rapid Method to Characterize Mutations in Transthyretin in Cerebrospinal Fluid from Familial Amyloidotic Polyneuropathy Patients by Use of Matrix-assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry
Authors: Bergquist Jonas , Andersen Oluf , Westman Ann 
Published: January 2020

Abstract
Background: Familial amyloidotic polyneuropathy (FAP) type I, the most common dominantly inherited form of amyloidosis, is caused by a Val-to-Met point mutation at position 30 (Val30→Met) in the protein transthyretin. Mass spectrometric analysis can identify modification of proteins, such as point mutations, acetylation, phosphorylation, sulfation, oxidation, and glycosylation.
Methods: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) spectra from cerebrospinal fluid (CSF) drawn from a patient with FAP were compared with CSF from controls. We also isolated transthyretin with a Centrisart molecular size cutoff filter and performed high-accuracy peptide mass mapping to localize the site of the amino acid substitution (Val30→Met).
Results: Mass spectra of transthyretin were produced directly from human CSF as well as from CSF after a simple prepurification method without immunoprecipitation. On-target tryptic digestion and MALDI-MS verified mass spectrometric peak identification. The point mutation was still detectable in CSF after hepatic transplantation.
Conclusions: It is possible to diagnose FAP by a rapid MALDI-TOF MS analysis using only 100 μL of CSF, with only 250 nL actually consumed on target. The approach may also be useful to monitor production of mutated transthyretin by choroid plexus, especially after liver transplantation.