bluuebunny/crossref_metadata_2025_split huggingface dataset:
Compound Heterozygous Hemochromatosis Genotype Predicts Increased Iron and Erythrocyte Indices in Women
Authors: Rossi Enrico , Olynyk John K , Cullen Digby J , Papadopoulos George , Bulsara Max , Summerville Lesa , Powell Lawrie W 
Published: January 2020

AbstractBackground: Women who inherit heterozygosity for the C282Y mutation of the HFE gene may have increased serum iron indices and hemoglobin and are less likely to develop iron deficiency compared with women with the wild-type genotype.Methods: We performed a cross-sectional analysis of 497 women 20–44 years of age and 830 women &gt;51 years of age drawn from the Busselton (Australia) population study to assess the effects of the HFE genotype on serum iron and hematology indices.Results: Heterozygosity for the C282Y mutation occurred in 13.8% of the study population, comprising 11.8% C282Y wild-type heterozygotes and 2.0% C282Y/H63D compound heterozygotes. In the younger age group, C282Y wild-type women did not have significantly increased serum iron, transferrin saturation, or hemoglobin values, and were not protected from developing iron deficiency, compared with women of the same age with the wild-type genotype. Young compound heterozygous women had higher means for serum iron (25.0 vs 16.9 μmol/L; P &lt;0.001), transferrin saturation (42.0% vs 25.6%; P &lt;0.05), hemoglobin (139.4 vs 132.3 g/L; P &lt;0.05), and corpuscular volume (91.1 vs 87.7 fL; P &lt;0.05), and a higher median ferritin (53 vs 44 μg/L; P &lt;0.05) compared with the wild-type genotype. Similar results were observed for compound heterozygotes in the &gt;51 years age group.Conclusions: Women with the compound heterozygous HFE genotype C282Y/H63D, but not the C282Y wild-type genotype, had increased values for serum iron and transferrin saturation, and the younger age group also had increased hemoglobin values. We conclude that the compound heterozygous genotype may have a beneficial effect in protecting women from iron deficiency.
Expression of Matrix Metalloproteinase-2 and -9 and Their Inhibitors in Peripheral Blood Cells of Patients with Chronic Hepatitis C
Authors: Lichtinghagen Ralf , Huegel Omar , Seifert Thomas , Haberkorn Christian I , Michels Dirk , Flemming Peer , Bahr Matthias , Boeker Klaus H W 
Published: January 2020

AbstractBackground: To clarify whether circulating matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) can be used as serum markers of fibroproliferation in chronic liver diseases, we studied the expression of MMP-2 and MMP-9 in relation to TIMP-1 and TIMP-2 in peripheral blood mononuclear leukocytes (MNLs) and polymorphonuclear leukocytes (PMLs), and compared this expression to circulating concentrations and hepatic histology in patients with chronic active hepatitis C (CAH).Methods: Quantitative reverse transcription-PCR/ELISA assays were performed for MMP and TIMP RNA, and corresponding circulating protein concentrations were studied by ELISA in 20 healthy controls, 40 patients with CAH, and 20 patients with hepatitis C-induced cirrhosis (Ci).Results: MMP-2 mRNA was found almost exclusively in the liver, MMP-9 mRNA in leukocytes. TIMP RNA-equivalents were decreased in MNLs of CAH patients, but neither MMP-9 nor TIMP RNA expression showed any correlation to the extent of inflammation and fibrosis. MMP-2 and TIMP-1 protein concentrations were increased in Ci patients and showed a wide overlap in CAH patients and healthy controls. MMP-9 values were lower in CAH and Ci patients than in healthy controls. TIMP-2 values showed a wide overlap in all three groups. The MMP-2/TIMP-1 and MMP-9/TIMP-1 ratios were lower in Ci patients than in healthy controls; the MMP-2/TIMP-2 and MMP-9/TIMP-2 ratios were not different. Circulating TIMP-1 and the MMP-2/TIMP-1 ratio correlated to the inflammatory activity in liver biopsies, but only the circulating MMP-2/TIMP-1 ratio also correlated with the degree of fibrosis.Conclusions: Peripheral blood cell expression of MMP-2, MMP-9, and TIMP revealed no correlation with the circulating concentrations of these proteins. Only the circulating MMP-2/TIMP-1 ratio correlated to the histological degree of fibrosis in hepatitis C and should be further evaluated as a progression marker in patients with chronic liver disease.
Very Small Apolipoprotein A-I-containing Particles from Human Plasma: Isolation and Quantification by High-Performance Size-Exclusion Chromatography
Authors: Nanjee M Nazeem , Brinton Eliot A 
Published: January 2020

AbstractBackground: Very small apolipoprotein (apo) A-I-containing lipoprotein (Sm LpA-I) particles with pre-β electrophoretic mobility may play key roles as “nascent” and/or “senescent” HDL; however, methods for their isolation are difficult and often semiquantitative.Methods: We developed a preparative method for separating Sm LpA-I particles from human plasma by high-performance size-exclusion chromatography (HP-SEC), using two gel permeation columns (Superdex 200 and Superdex 75) in series and measuring apo A-I content in column fractions in 30 subjects with HDL-cholesterol (HDL-C) concentrations of 0.4–3.83 mmol/L.Results: Three major sizes of apo A-I-containing particles were detected: an ∼15-nm diameter (∼700 kDa) species; a 7.5–12 nm (100–450 kDa) species; and a 5.8–6.3 nm species (40–60 kDa, Sm LpA-I particles), containing 0.2–3%, 80–96%, and 2–15% of plasma total apo A-I, respectively. Two subjects with severe HDL deficiency had increased relative apo A-I content in Sm LpA-I: 25% and 37%, respectively. The percentage of apo A-I in Sm LpA-I correlated positively with fasting plasma triglyceride concentrations (r = 0.581; P &lt;0.0005) and inversely with total apo A-I (r = −0.551; P &lt;0.0013) and HDL-C concentrations (r = −0.532; P &lt;0.0017), although the latter two relationships were largely attributable to extremely hypoalphalipoproteinemic subjects. The percentage of apo A-I in Sm LpA-I correlated with that in pre-β-migrating species by crossed immunoelectrophoresis (r = 0.98; P &lt;0.0001; n = 24) and with that in the d &gt;1.21 kg/L fraction by ultracentrifugation (r = 0.86; P &lt;0.001; n = 20). Sm LpA-I particles, on average, appear to contain two apo A-I and four phospholipid molecules but little or no apo A-II, triglyceride, or cholesterol.Conclusions: We present a new HP-SEC method for size separation of native HDL particles from plasma, including Sm Lp A-I, which may play important roles in the metabolism of HDL and in its contribution(s) to protection against atherosclerosis. This method provides a basis for further studies of the structure and function of Sm Lp A-I.
Leukocyte Counts in Cerebrospinal Fluid with the Automated Hematology Analyzer CellDyn 3500 and the Urine Flow Cytometer UF-100
Authors: Ziebig Reinhard , Lun Andreas , Sinha Pranav 
Published: January 2020

AbstractBackground: The counting of leukocytes and erythrocytes in cerebrospinal fluid (CSF) is still performed microscopically, e.g., using a chamber in most laboratories. This requires sufficient practical experience, is time-consuming, and may constitute a problem in emergency diagnostics. Specific automated systems for CSF cell counting are not available at present.Methods: We tested the hematology analyzer CellDyn 3500 (CD) and the urine flow cytometer UF-100 (UF), which are not designed for CSF analysis. We studied &gt;104 samples with both analyzers, and the counts obtained were compared with the reference method (Fuchs-Rosenthal chamber).Results: Good linearity in the medically relevant range of 15 × 106 to 1000 × 106 leukocytes/L and a high degree of within-run accuracy were seen for both analyzers. Cell counting on the UF was excellent, especially when low cell counts were encountered (CV, 4.9% compared with 28% observed for the CD). Method comparison showed that identical results could be detected for a majority of the count pairs. For a few samples, there was a discrepancy between the results from the analyzers and the counting chamber. In most cases, these were CSF samples containing a high proportion of lymphocytes. For these samples, the CD result led to a false-positive high leukocyte count, and on the UF these cells were not allocated to the leukocyte population, thus leading to false-negative counts.Conclusions: Both analyzers should not be used for CSF cell counting in all cases at present. However, once the technical and software problems have been solved, routine use of the two analyzers for CSF analysis should be seriously contemplated.
False Positivity in a Cyto-ELISA for Anti-Endothelial Cell Antibodies Caused by Heterophile Antibodies to Bovine Serum Proteins
Authors: Revelen Ronan , Bordron Anne , Dueymes Maryvonne , Youinou Pierre , Arvieux Josiane 
Published: January 2020

AbstractBackground: ELISAs with fixed endothelial cells or cell lines are widely used screening tests for anti-endothelial cell antibodies (AECAs), but spurious increases occur. We examined interferences by heteroantibodies and means to eliminate them.Methods: AECAs were measured by ELISA on fixed layers of the human endothelial cell line, EA.hy 926, in a panel of 60 patient serum samples diluted in bovine serum albumin. Heteroantibodies against fetal calf serum (FCS) proteins were demonstrated and characterized in an ELISA—the interference assay—that used FCS-coated plates and Tween 20-containing buffer as blocking agent and sample diluent, as well as by immunoblotting.Results: In 12 of 60 patient serum samples, spurious increases of AECA titers were produced by endogenous antibodies reacting with FCS proteins from culture medium that were coated onto the solid-phase at the time of cell plating. This mechanism of interference was supported experimentally by exposing extracellular matrix, varying cell density, and incubating wells with FCS alone. The heterophile antibodies were mainly IgG and IgA, and in inhibition experiments, they recognized serum proteins from goat, sheep, and horse. Washing cells free of FCS before plating, or adding FCS (100 mL/L) to the patient sample diluent eliminated spurious signals from all 30 tested sera, but the latter method had practical advantages.Conclusions: Antibodies against animal serum proteins are a frequent cause of erroneous results in cyto-ELISAs. The interference can be eliminated by simple antibody absorption in FCS-containing dilution buffer.
Plasma DNA as a Prognostic Marker in Trauma Patients
Authors: Lo Y M Dennis , Rainer Timothy H , Chan Lisa Y S , Hjelm N Magnus , Cocks Robert A 
Published: January 2020

Abstract
Background: Recently, much interest has developed in the potential use of plasma DNA as a diagnostic and monitoring tool. We hypothesized that plasma DNA is increased in patients with trauma and may be prognostic in such patients.
Methods: We studied 84 patients who had sustained an acute blunt traumatic injury. We measured plasma DNA by a real-time quantitative PCR assay for the β-globin gene. Blood samples were collected at a median time of 60 min following injury. Blood samples were also obtained from 27 control subjects.
Results: The median plasma DNA concentrations in the control, minor/moderate trauma (Injury Severity Score &lt;16; n = 47), and major trauma (Injury Severity Score ≥16; n = 37) groups were 3154 kilogenome-equivalents/L, 13 818 kilogenome-equivalents/L, and 181 303 kilogenome-equivalents/L, respectively. Plasma DNA concentrations in patients with adverse outcomes, including acute lung injury, acute respiratory distress syndrome, and death, had 11.6- to 12-fold higher plasma DNA concentrations than those who did not develop these complications. At a cutoff of 232 719 kilogenome-equivalents/L, the sensitivities of plasma DNA analysis for the prediction of acute lung injury, acute respiratory distress syndrome, and death were 100% (95% confidence interval, 100–100%), 100% (95% confidence interval, 100–100%), and 78% (95% confidence interval, 40–97%), respectively. The respective specificities were 81% (95% confidence interval, 71–89%), 80% (95% confidence interval, 70–88%), and 82% (95% confidence interval, 71–90%).
Conclusions: Plasma DNA is increased after trauma and may be a potentially valuable prognostic marker for these patients.
Analysis of Folate Form Distribution by Affinity Followed by Reversed-Phase Chromatography with Electrochemical Detection
Authors: Bagley Pamela J , Selhub Jacob 
Published: January 2020

AbstractBackground: Naturally occurring folates exist in multiple forms, differing in pteridine ring structure and number of glutamate residues. The ability to measure these folate coenzymes in tissues and cells gives important information about in vivo folate metabolism.Methods: Folates were heat-extracted from biological samples. A two-column HPLC system with four-channel coulometric electrochemical detection was used for analysis. An affinity column was used first to purify folates from the extract. Purified folates were eluted from the affinity column onto a phenyl analytical column, utilizing a switching valve, and folate forms were separated using an acetonitrile gradient.Results: Folate forms differing in pteridine ring structure and number of glutamate chain residues were identified by retention time and characteristic response across the channels of the detector. Folates were quantified by comparison to an external calibration mixture. Limits of detection for pentaglutamyl folates ranged from 0.21 pmol for tetrahydrofolate to 0.41 pmol for 5-methyltetrahydrofolate. CVs (n = 5) for peaks containing 9–67 pmol of folate were 0.6–6.4% (within day) and 5.2–8.4% (between days). CVs (n = 5) for peaks containing 0.9–3.5 pmol folate were 5.7–16% (within day) and 8.4–13% (between days).Conclusions: This automated HPLC system allows the simultaneous determination of polyglutamyl forms of folates from biological samples, including tetrahydrofolate, 5-methyltetrahydrofolate, formylated folates, and pteroylglutamate. The low detection limits allow analysis of folate form distribution in human samples such as erythrocytes and lymphocytes.
Clinical Efficacy of Three Assays for Cardiac Troponin I for Risk Stratification in Acute Coronary Syndromes: A Thrombolysis In Myocardial Infarction (TIMI) 11B Substudy
Authors: Morrow David A , Rifai Nader , Tanasijevic Milenko J , Wybenga Donald R , de Lemos James A , Antman Elliott M 
Published: January 2020

AbstractBackground: Significant analytic variability exists between the multiple assays for cardiac troponin I (cTnI) approved for clinical use. Until adequate cTnI standardization is possible, an evidence-based approach evaluating each assay at specific thresholds appears warranted.Methods: We examined the efficacy of three cTnI assays for predicting death, myocardial infarction (MI), or the composite of death, MI, or urgent revascularization at 43 days among patients with non-ST-elevation acute coronary syndromes enrolled in the Thrombolysis In Myocardial Infarction (TIMI) 11B study.Results: Six hundred eighty-one patients with serum samples obtained at baseline and/or 12–24 h had cTnI determined using all three assays. Baseline cTnI was ≥0.1 μg/L for 368, 395, and 418 patients with the Bayer Immuno 1TM, ACS:180®, and Dimension® RxL assays, respectively. Correlation coefficients for the RxL with the ACS:180 and Bayer Immuno 1 results were 0.89 (P = 0.0001) and 0.87 (P = 0.0001), with a coefficient of 0.92 (P = 0.0001) for the ACS:180 and Bayer Immuno 1 assays. Patients with cTnI ≥0.1 μg/L were at increased risk for death or MI by 43 days (relative risk, 2.2–3.0; P &lt;0.0006), regardless of the assay used. This prognostic capacity persisted among those with creatine kinase MB isoenzyme concentrations within the reference interval. Moreover, cTnI was the strongest multivariate predictor of death, MI, or urgent revascularization with adjusted odds ratios of 2.1–2.9 (P &lt;0.0006).Conclusion: This study demonstrates the prognostic efficacy of three independently developed cTnI assays at a threshold of 0.1 μg/L for the prediction of adverse clinical outcomes among patients with non-ST-elevation acute coronary syndromes.
Propofol-associated Rhabdomyolysis with Cardiac Involvement in Adults: Chemical and Anatomic Findings
Authors: Stelow Edward B , Johari Vandita P , Smith Stephen A , Crosson John T , Apple Fred S 
Published: January 2020

Abstract
Propofol, a central-acting sedative agent, has been implicated in the development of rhabdomyolysis in children. We describe two adults who developed rhabdomyolysis after receiving high rates of propofol infusion. Rhabdomyolysis of both skeletal and cardiac muscle was suggested in both patients by marked increases of creatine kinase (&gt;170 000 U/L) and cardiac troponin I (11 and 46 μg/L in patients one and two, respectively). Creatine kinase and cardiac troponin I values were highly correlated in each patent (r = 0.786 and 0.988 in patients one and two, respectively). Autopsy of one patient confirmed the diagnosis of skeletal and cardiac rhabdomyolysis.
Cardiac Troponins I and T Are Biological Markers of Left Ventricular Dysfunction in Septic Shock
Authors: ver Elst Kristien M , Spapen Herbert D , Nguyen Duc Nam , Garbar Christian , Huyghens Luc P , Gorus Frans K 
Published: January 2020

Abstract
Background: Cardiac depression in severe sepsis and septic shock is characterized by left ventricular (LV) failure. To date, it is unclear whether clinically unrecognized myocardial cell injury accompanies, causes, or results from this decreased cardiac performance. We therefore studied the relationship between cardiac troponin I (cTnI) and T (cTnT) and LV dysfunction in early septic shock.
Methods: Forty-six patients were consecutively enrolled, fluid-resuscitated, and treated with catecholamines. Cardiac markers were measured at study entry and after 24 and 48 h. LV function was assessed by two-dimensional transesophageal echocardiography.
Results: Increased plasma concentrations of cTnI (≥0.4 μg/L) and cTnT (≥0.1 μg/L) were found in 50% and 36%, respectively, of the patients at one or more time points. cTnI and cTnT were significantly correlated (r = 0.847; P &lt;0.0001). Compared with cTnI-negative patients, cTnI-positive subjects were older, presented higher Acute Physiology and Chronic Health Evaluation II scores at diagnosis, and tended to have a worse survival rate and a more frequent history of arterial hypertension or previous myocardial infarction. In contrast, the two groups did not differ in type of infection or pathogen, or in dose and type of catecholamine administered. Continuous electrocardiographic monitoring in all patients and autopsy in 12 nonsurvivors did not disclose the occurrence of acute ischemia during the first 48 h of observation. LV dysfunction was strongly associated with cTnI positivity (78% vs 9% in cTnI-negative patients; P &lt;0.001). In multiple regression analysis, both cTnI and cTnT were exclusively associated with LV dysfunction (P &lt;0.0001).
Conclusions: These findings suggest that in septic shock, clinically unrecognized myocardial cell injury is a marker of LV dysfunction. The latter condition tends to occur more often in severely ill older patients with underlying cardiovascular disease. Further studies are needed to determine the extent to which myocardial damage is a cause or a consequence of LV dysfunction.
Dual-Label Time-resolved Immunofluorometric Assay of Free and Total Prostate-specific Antigen Based on Recombinant Fab Fragments
Authors: Eriksson Susann , Vehniäinen Markus , Jansén Tove , Meretoja Ville , Saviranta Petri , Pettersson Kim , Lövgren Timo 
Published: January 2020

AbstractBackground: Recombinant Fab fragments are attractive as reagents for novel sandwich immunoassays, but no such assays have been described. We developed a dual-label two-site immunoassay based entirely on recombinant Fab fragments and compared it to the same assay with intact monoclonal antibodies.Methods: The capture Fab fragment, which binds free prostate-specific antigen (PSA) and PSA in complex with α1-antichymotrypsin on an equimolar basis, is site-specifically biotinylated and attached to the solid phase in streptavidin-coated microtitration wells. The Fab fragment that detects only free PSA is site-specifically labeled with a fluorescent europium chelate, and the Fab fragment that detects both free and serpin-complexed PSA in an equimolar fashion is labeled with a fluorescent terbium chelate. Time-resolved fluorescence is used to measure both europium and terbium signals in one well.Results: The detection limits of the assay (mean + 3 SD of zero calibrator) were 0.043 and 0.28 μg/L, respectively, for free and total PSA. The within-run and day-to-day CVs were 2–11% and 4–10%, respectively. Mean recoveries were 93% and 98% in female and male sera, respectively. Compared with the commercial ProStatus PSA Free/Total Assay, the intercepts of the regression equations (r &gt;0.99) were not significantly different from zero, and the slopes were 0.95–1.01. In one female serum sample, PSA was falsely increased with the monoclonal assay but was undetectable with the recombinant assay.Conclusions: The performance of this novel assay based on recombinant components is comparable to a conventional assay based on monoclonal antibodies. The more complete control of the essential characteristics of site-specifically derivatized recombinant Fab fragments will be valuable for the design of miniaturized and multianalyte assay concepts where correct antibody orientation, density, and capacity as well as uncompromised binding affinity are required.
Short- and Long-Term Effects of Ibandronate Treatment on Bone Turnover in Paget Disease of Bone
Authors: Woitge Henning W , Oberwittler Heike , Heichel Silke , Grauer Andreas , Ziegler Reinhard , Seibel Markus J 
Published: January 2020

AbstractBackground: In Paget disease of bone (PD), serum total alkaline phosphatase (TAP) is a valid marker of disease activity. The aim of the present longitudinal study was to compare TAP with new and potentially more specific markers of bone turnover in bisphosphonate-treated patients with PD.Methods: Twenty patients with active PD were studied before and after treatment with 2 mg of intravenous ibandronate over a period of 12 months. TAP (by colorimetry), serum bone-specific alkaline phosphatase (BAP; by enzyme immunoassay), serum osteocalcin (OC; by ELISA), serum bone sialoprotein (BSP; by RIA), and urinary total pyridinoline (PYD; by HPLC) and deoxypyridinoline (DPD; by HPLC) were measured as markers of bone turnover.Results: Before treatment, TAP, BAP, and BSP were increased in all 20 patients, whereas OC was increased in 10, PYD in 13, and DPD in 15 patients. Three months post treatment, nine patients showed normalized TAP values, and a ≥25% re-increase (i.e., relapse) was observed in all patients after 12 months. A normalization of BAP was achieved in six patients only. No significant changes were found for OC. BSP was decreased significantly at 24 h, and DPD at 48 h post treatment. A normalization of BSP was found in 8, of PYD in 18, and of DPD in 16 cases. Both PYD and DPD increased significantly from 9 months post treatment onward.Conclusions: Most markers of bone turnover show similar long-term changes after treatment of active PD with ibandronate. With regard to cost-effectiveness and assay performance, TAP remains the marker of choice in therapeutic monitoring of PD. However, more specific markers may improve the biochemical assessment of PD in certain situations.