1,720,958 research outputs found
Potential Peptide Biomarkers and Etiological Factors in the Cerebrospinal Fluid of Amyotrophic Lateral Sclerosis Patients
No full textUnique cerebrospinal fluid peptides: potential amyotrophic lateral sclerosis biomarkers and etiological factors
Full text linkAim: Amyotrophic lateral sclerosis (ALS) is a progressive disease of unknown etiology, characterized by degeneration of motoneurons and skeletal muscle strength decline that progressively evolves to respiratory failure and death. A key point in the therapeutic approach is to understand the pathological processes associated with disease evolution. In spite of intensive research on the molecular/cellular mechanisms involved in ALS initiation and progression disease etiology, unfortunately, poorly understood and there is no efficient specific/decisive treatment for ALS patients. The aims of the present study are to identify specific factors in the cerebrospinal fluid (CSF) of ALS patients and to test their potential relevance to the etiology of this disease. Methods: Peptides were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS). Motor activity of mice was tested by the Rota-rod test and peptide-induced inflammation was assessed by induction nitric oxide synthase activity in BV2 microglia cells. Results: Analysis of CSF samples of ALS patients (n = 15) detected two peptides, C-terminal fragments of transthyretin and osteopontin, which were absent in a control group (n = 15). In addition to being potential biomarker candidates, the relevancy of these peptides to the disease etiology was tested by assessing their effects on motor activity in mice and inflammation model in cell culture. Intranasal administration of the peptides reduced motor activity in the Rota-rod test and activated lipopolysaccharide-induced inflammation in BV2 microglia cells. Conclusions: These findings suggest that during ALS onset and progression two potentially neurotoxic peptides are formed, released, or penetrated the central nervous system thus inducing neuroinflammation and neurodegeneration
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
Reduced levels of alpha-1-antitrypsin in cerebrospinal fluid of amyotrophic lateral sclerosis patients: a novel approach for a potential treatment
Full text linkAbstract
Background: Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative motor neuron disease that
involves activation of the immune system and inflammatory response in the nervous system. Reduced level of
the immuno-modulatory and anti-inflammatory protein alpha-1-antitrypsin (AAT) is associated with
inflammation-related pathologies. The objective of the present is to determine AAT levels and IL-23 in the
cerebrospinal fluid (CSF) of ALS patients and control group.
Findings: CSF samples from newly diagnosed ALS patients and age-matched controls were analyzed for AAT and
IL-23 by ELISA and magnetic luminex screening, respectively. A statistically significant reduction of 45 % in mean
AAT levels was observed in the CSF of ALS patients (21.4 μg/ml) as compared to the control group (mean 38.8 μg/ml,
p = 0.013). A statistically significant increase of 30.8 % in CSF mean levels of the pro-inflammatory cytokine IL-23 was
observed in ALS patients (1647 pg/ml) in comparison to the controls (1259 pg/ml, p = 0.012). A negative correlation
coefficient (r = −0.543) was obtained by linear regression analysis of the two measured parameters (p = 0.036).
Conclusions: Reduced AAT and elevated IL-23 CSF levels support the notion of neuroinflammatory process occurring
in ALS patients. Increasing AAT levels in the patients’ nervous system should be further investigated as a new
therapeutic approach and a novel potential tool for ALS treatment
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
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