1,721,002 research outputs found
PSMA - Targeted Clinical Molecular Imaging of Atherosclerosis:Correlation with Cardiovascular Risk Factors
No full textAim The early diagnosis of atherosclerotic changes to prevent ischemic events represents a clinical challenge. Prostate-specific membrane antigen (PSMA) as an established diagnostic in the field of prostate cancer also appears to detect neovascularization and inflammation in other diseases. We hypothesized that it might be also suited for detection of inflammation in atherosclerosis. Methods We analyzed data of 78 prostate cancer patients who received a PSMA ligand PET/CT for re-staging. The cardiovascular risk factors (CVRF) of each patient were documented. Target-to-background-ratios (TBR) were calculated from the individual uptake values for three different sections of thoracic aorta [ascending (AA) and descending aorta (AD), aortic arch (AoAC)]. Statistical analyses included a linear regression analysis with the PSMA ligand uptake values of the different arterial segments versus different CVRF as independent variables. Results The meanTBRmax was measured highest in the AoAC (1.66 +/- 0.33) compared to both other vessel sections (AA: 1.46 +/- 0.21, p=0.001; AD: 1.59 +/- 0.41, p=0.371). There was a correlation between the PSMA ligand uptake in all measured segments of the aorta and BMI, but only a significant correlation in the ascending aorta (r=0.347, p=0.001). This was confirmed in a subgroup analysis, which showed significantly higher uptake values in preadiposity (BMI >25) and obesity (BMI >30) patients in the ascending aorta (p=0.048). Conclusion PSMA ligand uptake in the ascending aorta was linked to BMI. PET detection of vascular PSMA ligand uptake may be indicative of vessel wall inflammation to some extent. However, PSMA ligands appear to be less suitable than other tracers for this purpose, given their absent correlation with most established CVRFs
Screening of extravascular findings in pulmonary embolism computer tomography: 397 patients with 1950 non-pulmonary artery findings
No full textObjectives The aim of this study was to investigate the possible benefits from computed tomography scans of patients with a suspected pulmonary artery embolism with a focus on relevant extravascular findings. Methods A total of 400 consecutive computed tomography pulmonary angiographies were evaluated. Computed tomography scans were analyzed in detail for the presence of pulmonary artery embolisms, as well as any other findings. Extra-artery discoveries were classified into none-relevant (Group A), intermediate (Group B), or relevant (Group C) findings. Results Aggregated computed tomography pulmonary angiographies detected other diagnosis than pulmonary artery embolism in 236 patients (59%). There were 1950 non-pulmonary artery embolism findings (4.9 per patient; n = 397). In the pulmonary artery embolism group, there were 447 extra-pulmonary artery embolism findings (5.2 per patient; n = 86) and in the non-pulmonary artery embolism group, 1503 findings (4.8 per patient; n = 311). Patients with pulmonary artery embolism had a significantly higher rate of pro-coagulate risk factors ( p < 0.001). Conclusions Computed tomography pulmonary angiographies may help to identify further diagnoses. This study represents a retrospective review of a single center experience for incidental computed tomography findings during pulmonary artery embolism work-up and emphasizes the importance of analyzing the whole field-of-view. </jats:sec
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Spontaneous cell fusion between small cell lung cancer cells and bone marrow-derived human mesenchymal stem cells
No full textMesenchymale Stammzellen des Knochenmarkes sezernieren das Chemokin CXCL12, das vom Chemokinrezeptor CXCR4 auf Zellen des kleinzelligen Bronchialkarzinomes gebunden wird und so zu einer Wachstumsstimulation führt, weshalb es vermutlich zu einer besonders häufigen Metastasierung des kleinzelligen Bronchialkarzinoms in das Knochenmark kommt. Durch Fusion von CXCR4+ Tumorzellen mit CXCL12 exprimierenden Stammzellen könnten so Zellen mit einem aktivierten autokrinen Signalweg entstehen.
Ziel dieser Arbeit war es daher, die Frage einer möglichen Zellfusion zwischen Stamm- und Tumorzellen für vier Bronchialkarzinomzelllinien (H82, SW2, OH1, OH3) zu untersuchen. Zusätzlich wurde untersucht, ob die Fusionsfrequenz pharmakologisch beeinflusst werden kann.
Das seltene Ereignis einer Tumorzell-/Stammzellfusion konnte fluoreszenzmikroskopisch, durchflusszytometrisch und in der Laser Scanning Zytometrie bestätigt und quantifiziert werden. Dazu wurde eine direkte, quantitative Nachweismethode für Zellfusionen mittels Durchflusszytometrie entwickelt. Die höchste Fusionsfrequenz unter den Bronchialkarzinomzellen konnte dabei bei der Zelllinie OH3 beobachtet werden, nämlich 2,14 ± 0,64 ‰. Die Fusionsfrequenz konnte sowohl durch Gabe des - die Zellmembranfluidität beeinflussenden - β HMG-CoA-Reduktaseinhibitors Atorvastatin als auch durch Blockade des Rezeptors CXCR4 mittels des Bizyklams AMD3100 in signifikantem Maße erhöht werden. Dabei konnte ausgeschlossen werden, dass durch das Statin eine relevante Beeinflussung der Aufnahme an Quantum Dots erfolgt. Mit dem verwendeten blockierenden Antikörper gegen CXCR4 ließ sich die Fusionsfrequenz hingegen nicht beeinflussen. Die nähere, exemplarisch für die Zelllinie H82 durchgeführte durchflusszytometrische Charakterisierung der durch Atorvastatin hervorgerufenen Veränderungen in der Glykokonjugatzusammensetzung der Zellmembran zeigte eine signifikant erhöhte Expression von komplexen Kohlenhydratresten.Bone marrow-derived mesenchymal stem cells produce the chemokine CXCL12 which is bound by the chemokine receptor CXCR4 on the surface of small cell lung cancer cells preferably metastasizing into the bone marrow. It is known to stimulate cell proliferation. Cell fusion between these cell types might lead to an activated autocrine signal loop
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
