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Evaluation of two automatic systems for measurement of the erythrocyte sedimentation rate
Get PDFOur aim was to compare two different automated devices for the measurement of the length of erythrocyte sedimentation rate (LSRB) in order to decrease the amount of blood sample collected. We compared VES-MATIC 60 (DIESSE s.p.a.,Grosseto, Italy) with VES-CUBE 200 (DIESSE s.p.a.,Grosseto, Italy), that requires K2-EDTA and sodium-citrate blood samples, respectively. A total of 160 whole blood samples from patients of the Laboratory Medicine of University Hospital “Tor Vergata” Rome were included in this study; LSRB was determined following ICSH recommendations. Linear regression analysis was used for accuracy study; Reproducibility was assessed using an internal quality control for at least one month (mean = 6.93, SD = 0.775 CV=10.5).
Our data showed statistically significant correlation between the two different systems, when the data of VES-CUBE 200 were adjusted to 18°C by Manley’s normogramm. Moreover, both systems presented a good reproducibility and similar CV value.
In conclusion, both systems can be used for LSRB determination with the same range of reference; in addition, our previous study showed that LSRB values on plasma-citrate or on K2-EDTA were the same on VES-MATIC 60, therefore the automatic system for LSRB measurement, VES-CUBE 200, shows important advantages on one hand it decreases the amount of whole blood collected being the sample undiluted, on the other hand the test can be performed on the same tube collected for hemochrome analysis, using K2-EDTA as anticoagulant.
1)Caswell M, Stuart J. Assessment of Diesse Ves-matic automated system for measuring erythrocyte sedimentation rate. J Clin Pathol 1992 Feb;45(2):18
Length of sedimentation reaction in blood: a comparison between plasma citrate and K2-EDTA blood samples.
Get PDFIntroduction
The erythrocyte sedimentation rate (ESR), now more appropriately referred to as "length of sedimentation reaction in blood (LSRB)", remains the most widely used laboratory test for monitoring the course of infections, inflammatory diseases and some types of cancer. In addition, it is simple and low-cost. The most commonly used procedures for LSRB determination requires plasma-citrate blood samples, following ICSH (International Committee for Standardization in Haematology) recommendations. It is no unlikely that LSRB blood samples are insufficient, especially in children and in haemathological patients. In order to resolve this inconvenient, we compared LSRB measurement in plasma citrate and in K2-EDTA blood samples.
Methods
We performed our study on 300 whole blood samples from patients of Medicine Laboratory of University Hospital “Tor Vergata” Rome, using an automated procedure (VES-MATIC 60 DIESSE s.p.a.,Grosseto, Italy)
Plasma citrate blood samples were analyzed and used as control, whereas K2-EDTA blood samples were transferred in tubes containing sodium-citrate and then analyzed.
Statistical correlation was performed using Pearson’s correlation.
Results and Discussion
Results of linear regression are shown in Figure. There was a close correlation in LSRB measurements between plasma citrate and in K2-EDTA The regression line had a slope of 0.995 and an intercept of -0.42. The LSRB is a non specific laboratory test widely used in clinical practice. However, this test is used conventionally to detect acute or chronic systemic inflammation in a number of diverse conditions and to monitor the response to therapy. Our results demonstrate that there are not differences between citrate and K2-EDTA plasma therefore LSRB can be eventually measured from the tube collected for hemochrome analysis and so resolve the inconvenient of insufficient samples; besides the use of samples anticoagulated with K2 EDTA can widely reduce the workload in clinical laboratories
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Identification of an alternative transcript of ABCA1 gene in different human cell types.
No full textAscorbic acid recycling in N-myc amplified human neuroblastoma cells
No full textThe present study investigated the ability of two neuroblastoma cell lines (SK-N-SH, with one copy of N-myc, and SK-N-BE(2), with over 150 copies of N-myc) to recycle ascorbate by quantifying semidehydroascorbate reductase and dehydroascorbate reductase activities. Both cell lines expressed dehydroascorbate activity (SK-N-SH 28.4+/-9.8, SK-N-BE(2) 21.7+/-5.2 nmol/min/mg protein). Intracellular semidehydroascorbate activity was present only in SK-N-BE(2) cells (4.7+/-1.2 nmol/min/mg protein). Extracellular ascorbate was regenerated by semidehydroascorbate membrane activity, the activity of SK-N-BE(2) being twice that of SK-N-SH cells. The present data may explain the ability of the tumor to progress or regress through mechanisms involving both myc oncogene and apoptosis
Activation of different lipoxygenase isozymes induces apoptosis in human erythroleukemia and neuroblastoma cells
No full textWe investigated the ability of different hydroperoxides generated by lipoxygenase isozymes to induce programmed cell death (PCD) in human cells. Erythroleukemia K562 and neuroblastoma CHP100 cells were used, because they showed high basal activity of Lipoxygenase. The hydroperoxides generated by 5-, 12-, or 15-lipoxygenases from linoleate, linolenate, or arachidonate, and the corresponding hydroxides, were able to induce PCD in both cell types, in a concentration- and time-dependent manner. After 24 h, K562 and CHP100 cells showed 2.5- to 3.5-fold more apoptotic bodies than, the untreated controls. PCD elicited by lipoxygenase products was independent of intracellular glutathione concentration, and did not require mRNA transcription or protein synthesis. On the other hand, lipoxygenase products evoked an immediate and sustained rise in cytoplasmic calcium (within seconds), followed by mitochondrial uncoupling (within hours). Unlike the hydro(pero)xides, the terminal products of the arachidonate cascade (i.e., leukotrienes, prostaglandins and thromboxane) were not cytotoxic. (C) 2000 Academic Press
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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