Quality performance for indirect Xa inhibitor monitoring in patients using international external quality data

2020 ◽  
Vol 58 (11) ◽  
pp. 1921-1930 ◽  
Author(s):  
Martine J. Hollestelle ◽  
Felix J.M. van der Meer ◽  
Piet Meijer
Keyword(s):  
Quality Data ◽  
Low Molecular Weight ◽  
Factor X ◽  
External Quality ◽  
Danaparoid Sodium ◽  
Quality Performance ◽  
Low Concentrations ◽  
Comparison Of The Results ◽  
Insight Into ◽  
Over Time

AbstractObjectivesChromogenic anti-activated factor X (FXa) assays are currently the “gold standard” for monitoring indirect anticoagulants. However, anti-FXa has been shown to vary according to the choice of reagents. In the present study, the performance of anti-FXa measurement was evaluated in order to gain more insight into the clinical applications. Furthermore, the longitudinal coefficient of variation (CV) was studied to investigate whether there is improvement over time.MethodsLaboratory tests results were evaluated for samples spiked with unfractionated heparin (UFH), low-molecular-weight-heparin (LMWH), fondaparinux and danaparoid sodium. External quality assessment (EQA) data from multiple years were used from more than 100 laboratories.ResultsComparison of the results for all methods showed significant differences in measured values between the frequently used methods (ANOVA: p < 0.001). The largest differences were observed for LMWH and UFH measurements. These differences may be caused by differences in method composition, such as the addition of dextran sulphate. Substantial interlaboratory variation in anti-FXa monitoring was observed for all parameters, particularly at low concentrations. Our results showed that below 0.35 IU/mL, the CVs for UFH and LMWH increase dramatically and results below this limit should be used with caution.ConclusionsOur study demonstrates that the choice of the anti-FXa method is particularly important for UFH and LMWH measurement. The variation in measurements may have an effect on clinical implications, such as therapeutic ranges. Furthermore, the longitudinal EQA data demonstrated a constant performance and, in at least 50% of the cases, improvement in the CV% of the anti-Xa results over time.

Protamine Neutralization of the Release of Tissue Factor Pathway Inhibitor Activity by Heparins

1993 ◽  
Vol 70 (06) ◽  
pp. 0942-0945 ◽  
Author(s):  
Job Harenberg ◽  
Marietta Siegele ◽  
Carl-Erik Dempfle ◽  
Gerd Stehle ◽  
Dieter L Heene
Keyword(s):  
Tissue Factor ◽  
Binding Sites ◽  
Tissue Factor Pathway Inhibitor ◽  
Factor Xa ◽  
Protamine Sulfate ◽  
Low Molecular Weight ◽  
Factor X ◽  
Rebound Phenomenon ◽  
Tissue Factor Pathway ◽  
Kinetics Of

SummaryThe present study was designed to investigate the action of protamine on the release of tissue factor pathway inhibitor (TFPI) activity by unfractionated (UF) and low molecular weight (LMW) heparin in healthy individuals. 5000 IU UF-heparin or 5000 IU LMW-heparin were given intravenously followed by saline, 5000 U protamine chloride or 5000 U protamine sulfate intravenously after the 10 min blood sample. Then serial blood samples for the measurement of TFPI activity and anti-factor Xa- activity were taken, in order to detect a possible relation between the remaining anti-factor X a activity after neutralization of LMW-heparin with protamine and TFPI activity and to establish whether or not a rebound phenomenon of plasmatic TFPI occurs.There was no difference in the release and in the kinetics of TFPI by UF- and LMW-heparin with subsequent administration of saline. After administration of protamine TFPI activity decreased immediately and irreversibly to pretreatment values. There were no differences between protamine chloride and protamine sulfate on the effect of TFPI induced by UF- or LMW-heparin. No rebound phenomenon of TFPI activity occurred. In contrast anti-factor Xa- activity, as measured by the chromogenic S2222-assay, issued the known differences between UF- and LMW-heparin. The half-life of the aXa-effect of LMW-heparin was twice as long as of UF-heparin. Protamine antagonized UF-heparin completely and about 60% of the anti-factor Xa activity of LMW-heparin, using chromogenic S2222-method. No differences could be detected for protamine chloride and sulfate form of protamineIt is assumed that protamine displaces heparins from the binding sites of TFPI. There were no differences between UF- and LMW-heparin. The data indicate that the sustained antifactor Xa activity after antagonization of LMW-heparins as well as heparin rebound phenomena are not mediated by TFPI activity.

Dualities, Dialectics, and Paradoxes in Organizational Life

2018 ◽  
Keyword(s):  
Dynamic Systems ◽  
Empirical Studies ◽  
Organizational Studies ◽  
Organizational Life ◽  
Organizational Processes ◽  
Organization Studies ◽  
Process Studies ◽  
Convergence And Divergence ◽  
Insight Into ◽  
Over Time

Organizational contradictions and process studies offer interwoven and complementary insights. Studies of dialectics, paradox, and dualities depict organizational contradictions that are oppositional as well as interrelated such that they persistently morph and shift over time. Studies of process often examine how contradictions fuel emergent, dynamic systems and stimulate novelty, adaptation, and transformation. Drawing from rich conversations at the Eighth International Symposium on Process Organization Studies, the contributors to this volume unpack these relationships in more depth. The chapters explore three main, connected themes through both conceptual and empirical studies, including (1) offering insight into how process theorizing advances understandings of organizational contradictions; (2) shedding light on how dialectics, paradoxes, and dualities fuel organizational processes that affect persistence and transformation; and (3) exploring the convergence and divergence of dialectics, paradox, and dualities lenses. Taken together, this book offers key insights in order to inform persistent, contradictory dynamics in organizations and organizational studies.

The Oxford Handbook of the Brazilian Economy

2018 ◽  
Keyword(s):  
Direct Investment ◽  
Global Economy ◽  
Iron Ore ◽  
Structural Features ◽  
Economic Importance ◽  
Closed Economy ◽  
Current Characteristics ◽  
Insight Into ◽  
Contemporary Context ◽  
Over Time

Brazil constitutes a globally vital but troubled economy. It accounts for the largest GDP in Latin America and ranks among the world’s largest exporters of critical commodities including iron ore, soya, coffee, and beef. In recent years Brazil’s global economic importance has been magnified by a surge in both outward and inward foreign direct investment. This has served to further internationalize what has been historically a relatively closed economy. The purpose of this Handbook is to offer real insight into the Brazil’s economic development in contemporary context, understanding its most salient characteristics and analyzing its structural features across various dimensions. At a more granular level, this volume accomplishes the following tasks. First, it provides an understanding of the economy’s evolution over time and the connection of its current characteristics to this evolution. Second, it analyzes Brazil’s broader place in the global economy, and considers the ways in which this role has changed, and is likely to change, over coming years. Third, reflecting contemporary concerns, the volume offers an understanding, not only of how one of the world’s key economies has developed and transformed itself, but also of the ways in which this process has yet to be completed. The volume thus analyzes the current challenges facing the Brazilian economy and the kinds of issues that need to be tackled for these to be addressed.

scholarly journals Detecting bursty terms in computer science research

2019 ◽  
Vol 122 (1) ◽  
pp. 681-699 ◽  
Author(s):  
E. Tattershall ◽  
G. Nenadic ◽  
R. D. Stevens
Keyword(s):  
Computer Science ◽  
Historical Data ◽  
Science Research ◽  
Detection Algorithm ◽  
Trend Detection ◽  
Free Text ◽  
Research Topics ◽  
Computer Science Research ◽  
Insight Into ◽  
Over Time

AbstractResearch topics rise and fall in popularity over time, some more swiftly than others. The fastest rising topics are typically called bursts; for example “deep learning”, “internet of things” and “big data”. Being able to automatically detect and track bursty terms in the literature could give insight into how scientific thought evolves over time. In this paper, we take a trend detection algorithm from stock market analysis and apply it to over 30 years of computer science research abstracts, treating the prevalence of each term in the dataset like the price of a stock. Unlike previous work in this domain, we use the free text of abstracts and titles, resulting in a finer-grained analysis. We report a list of bursty terms, and then use historical data to build a classifier to predict whether they will rise or fall in popularity in the future, obtaining accuracy in the region of 80%. The proposed methodology can be applied to any time-ordered collection of text to yield past and present bursty terms and predict their probable fate.

Decomposition of Growth Curves into Growth Rate and Acceleration: a Novel Procedure to Monitor Bacterial Growth and the Time-Dependent Effect of Antimicrobials

2021 ◽  
Author(s):  
M. Luisa Navarro-Pérez ◽  
M. Coronada Fernández-Calderón ◽  
Virginia Vadillo-Rodríguez
Keyword(s):  
Growth Rate ◽  
Mathematical Models ◽  
Bacterial Growth ◽  
Time Course ◽  
Antimicrobial Agents ◽  
Numerical Procedure ◽  
Growth Curves ◽  
Predictive Microbiology ◽  
Insight Into ◽  
Over Time

In this paper, a simple numerical procedure is presented to monitor the growth of Streptococcus sanguinis over time in the absence and presence of propolis, a natural antimicrobial. In particular, it is shown that the real-time decomposition of growth curves obtained through optical density measurements into growth rate and acceleration can be a powerful tool to precisely assess a large range of key parameters [ i.e. lag time ( t 0 ), starting growth rate ( γ 0 ), initial acceleration of the growth ( a 0 ), maximum growth rate ( γ max ), maximum acceleration ( a max ) and deceleration ( a min ) of the growth and the total number of cells at the beginning of the saturation phase ( N s )] that can be readily used to fully describe growth over time. Consequently, the procedure presented provides precise data of the time course of the different growth phases and features, which is expected to be relevant, for instance, to thoroughly evaluate the effect of new antimicrobial agents. It further provides insight into predictive microbiology, likely having important implications to assumptions adopted in mathematical models to predict the progress of bacterial growth. Importance: The new and simple numerical procedure presented in this paper to analyze bacterial growth will possibly allow identifying true differences in efficacy among antimicrobial drugs for their applications in human health, food security, and environment, among others. It further provides insight into predictive microbiology, likely helping in the development of proper mathematical models to predict the course of bacterial growth under diverse circumstances.

Nubian Texts, Nubian Lives

2021 ◽  
pp. 771-786
Author(s):  
Giovanni R. Ruffini
Keyword(s):  
Economic History ◽  
World History ◽  
Valuable Insight ◽  
Documentary Evidence ◽  
Literary Genres ◽  
State Centralization ◽  
Insight Into ◽  
Flow Over Time ◽  
Over Time ◽  
Ebb And Flow

Nubian texts provide valuable insight into Nubian social and economic history. Accounts reveal economic priorities both secular and sacred. Documentary evidence hints at the nature of state centralization and the movement of goods and coins in and out of Nubia. Magic reveals Nubia’s deep-seated hopes and fears. Literature shows innovative theology and Nubia’s sense of its place in world history. Funerary inscriptions record the careers of the elite and their sense of their own place in the cosmos. But much is missing from the Nubian textual record as well, suggesting that major literary genres never indigenized in Nubia the way they did in Egypt or Ethiopia. Other genres ebb and flow over time, hinting at the economy of Nubian literacy and the processes through which it ultimately dies.

A comparative study of RFID adoption patterns in retail

2021 ◽  
pp. 1-20
Author(s):  
Narges Kasiri ◽  
G. Scott Erickson ◽  
Gerd Wolfram
Keyword(s):  
Comparative Study ◽  
Radio Frequency ◽  
Radio Frequency Identification ◽  
Structural Model ◽  
Slow Pace ◽  
The Us ◽  
Frequency Identification ◽  
Insight Into ◽  
Current Stage ◽  
Over Time

Radio frequency identification (RFID) has been viewed as a promising technology for quite some time. Initially developed a couple of decades ago, the technology has been accompanied by predictions of imminent widespread adoption since its beginnings. A majority of retailers and other users are now using or planning to use the technology. This paper employs a combination of the technology-organization-environment (TOE) model and the 3-S (substitution, scale, structural) model to analyze the long journey of RFID adoption in retail. Top retail executives in the US and Europe were interviewed to investigate RFID adoption patterns based on differences in technological, organizational, and environmental circumstances. As the retail industry is moving into a post-adoption era, these results demonstrate the current stage of retail RFID adoption, identify factors playing important roles over time as motivators or impediments, and provide some insight into the slow pace of adoption.

THE HEAP PARTS MOVEMENT ON THE SHAREBOARD SURFACE OF THE POTATO HARVESTING MACHINE

2021 ◽  
Vol 14(63) (1) ◽  
pp. 127-140
Author(s):  
Serhii HRUSHETSKYI ◽  
Vitaly YAROPUD ◽  
Ihor KUPCHUK ◽  
Ruslana SEMENYSHENA
Keyword(s):  
Mathematical Model ◽  
Experimental Studies ◽  
Separation Process ◽  
Kinematic Parameters ◽  
Quality Performance ◽  
Machine Operation ◽  
Degree Of Damage ◽  
Total Capacity ◽  
Comparison Of The Results

The article is devoted to the problem of the reduction of tubers mechanical damages while providing qualitative indicators of the potato heap separation process. Theoretical and experimental dependences of the influence of design and kinematic parameters of the machine operation on the quality performance are obtained. Within the field of experimental studies, a field installation was made to investigate the potato harvester as a whole on the efficiency of separation, the degree of damage, the magnitude of losses and the total capacity for aggregation. Comparison of the results of theoretical and experimental studies showed that the developed mathematical model of the process of separation of potato heap is adequate.

scholarly journals Proteolytic and peroxidatic reactions of commercial horseradish peroxidase with myelin basic protein

1978 ◽  
Vol 169 (3) ◽  
pp. 567-575 ◽  
Author(s):  
Wendy Cammer ◽  
Lesley Z. Bieler ◽  
William T. Norton
Keyword(s):  
Horseradish Peroxidase ◽  
Myelin Basic Protein ◽  
Basic Protein ◽  
Protein A ◽  
Low Molecular Weight ◽  
Basic Proteins ◽  
Molecular Weights ◽  
Low Concentrations ◽  
High Concentrations ◽  
A Minor

Degradation of myelin basic protein during incubations with high concentrations of horseradish peroxidase has been demonstrated [Johnson & Cammer (1977) J. Histochem. Cytochem.25, 329–336]. Possible mechanisms for the interaction of the basic protein with peroxidase were investigated in the present study. Because the peroxidase samples previously observed to degrade basic protein were mixtures of isoenzymes, commercial preparations of the separated isoenzymes were tested, and all three degraded basic protein, but to various extents. Three other basic proteins, P2 protein from peripheral nerve myelin, lysozyme and cytochrome c, were not degraded by horseradish peroxidase under the same conditions. Inhibitor studies suggested a minor peroxidatic component in the reaction. Therefore the peroxidatic reaction with basic protein was studied by using low concentrations of peroxidase along with H2O2. Horseradish peroxidase plus H2O2 caused the destruction of basic protein, a reaction inhibited by cyanide, azide, ferrocyanide, tyrosine, di-iodotyrosine and catalase. Lactoperoxidase plus H2O2 and myoglobin plus H2O2 were also effective in destroying the myelin basic protein. Low concentrations of horseradish peroxidase plus H2O2 were not active against other basic proteins, but did destroy casein and fibrinogen. Although high concentrations of peroxidase alone degraded basic protein to low-molecular-weight products, suggesting the operation of a proteolytic enzyme contaminant in the absence of H2O2, incubations with catalytic concentrations of peroxidase in the presence of H2O2 converted basic protein into products with high molecular weights. Our data suggest a mechanism for the latter, peroxidatic, reaction where polymers would form by linking the tyrosine side chains in basic-protein molecules. These data show that the myelin basic protein is unusually susceptible to peroxidatic reactions.

Hidden heirlooms: Keeping family secrets across generations

2017 ◽  
Vol 54 (3) ◽  
pp. 446-460 ◽  
Author(s):  
Ashley Barnwell
Keyword(s):  
Life Writing ◽  
National Narratives ◽  
Family Secrets ◽  
Secret Keeping ◽  
Colonial Policies ◽  
Insight Into ◽  
Over Time

This article explores how wider national narratives facilitate families’ choices about what information to keep secret over time. I argue that attention to the ways family secrets operate reveals how social and moral codes are both sustained and challenged on an intimate scale. The article also makes an argument for using life writing and literature to explore the often-illusive contours of family secrets. To illustrate, I examine Lynette Russell’s memoir A Little Bird Told Me: Family Secrets, Necessary Lies and Richard Flanagan’s novel Death of a River Guide. Anchoring the analysis within the transition from colonial to postcolonial societies, these texts lend insight into the collective practices families use to manage secrets and to construct socially sanctioned identities. The discussion foregrounds the enduring impact of colonial policies upon the intimate formation of families, and the role families play in reproducing and challenging these legacies via collective secret-keeping and silences.

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