1,720,980 research outputs found
Time related inhibition by methylguanidine in LPS-stimulated J774A.1 macrophages
Full text linkMethylguanidine (MG) is a nitrogen compound deriving from protein catabolism that accumulates in
Chronic kidney disease (CKD). Changes in monocyte functions have been recognised as one of the most
important key factor responsible for the immunological disorders associated with uremia and it has been
demonstrated that high blood concentrations of nitrogen compounds, as MG, could be responsible of
immunodisfunctions associated to uremic syndrome. Inducibie nitric oxide synthase (iNOS) and
cycloxygenase-2 (COX-2) and their respective metabolites, nitric oxide and prostaglandins, are a crucial step
both in the activation of immunoresponsive cells and in the mechanism of citotoxicity, NO mediated. It has
been previously reported the ability of MG to inhibit iNOS activity and expression both in vitro and in vivo.
The aim of this study is to evaluate if MG could interfere with macrophagic immunoresponses also modulating
iNOS and COX-2 at different time of incubation in J774A.1 stimulated with Lipopolysahharide from E.coli.
Our results demonstrated that MG exerted inhibitory effect on iNOS and COX-2. These effects are related to
incubation time thus highliting the detrimental effect of immune system by MG in uremic conditions
Guanidino compounds inhibit nitric oxide release in J774A.1 macrophages
Full text linkChronic kidney disease (CKD) has been usually associated with accumulation of some nitrogen compounds deriving from protein catabolism like creatine (CRT), creatinine (CRTN), guanidine (GN) and methylguanidine (MG) proposed as responsible of some manifestations of uremic syndrome. Changes in monocyte functions have been recognised as one of the most important key factor responsible for the immunological disorders associated with uremia and it has been demonstrated that high blood concentrations of nitrogen compounds, as MG, could be responsible of immunodisfunctions associated to uremic syndrome. Nitric oxide (NO) production by inducibie nitric oxide synthase (iNOS) is a crucial step both in the activation of immunoresponsive cells and in the mechanism of citotoxicity NO mediated. The aim of this study is to evaluate if some uremic toxins like CRT, CRTN, GN, MG could interfere in macrophagic immunoresponse modulating iNOS activity. Our results demonstrated that GN and MG exerted the stronger effect in inhibiting NO release; this effect was reverted by a L-ARG supplementation. Moreover macrophage co-exposure to GN and MG further enhanced the inhibitory effect on iNOS activity and expression. Our results demonstrated that, among tested compounds, GN and MG significantly affected iNOS activity and expression
Severe acidosis affects the anti-inflammatory properties of N-acetylcysteine on lipopolysaccharide-activated macrophages
Full text linkCritical illness is exemplified by a state of profound disruption in physiological homeostatic mechanisms. Tissue acidosis is an hallmark of inflammation/ischemia and tumor processes and although it remains uncertain whether there is a true cause-effect relation between acidosis and adverse clinical outcomes it remains a powerful marker of poor prognosis in critically ill patients. Patients with severe sepsis and septic shock exhibit a complex metabolic pattern of acidosis at intensive care unit admission, caused predominantly by hyperchloremic acidosis, which was more pronounced in non survivors. Abnormalities in systemic acid-base balance may also induce significant alterations in the immune response. In this study we evaluated the effect of N-acetylcysteine (NAC), an important cellular antioxidant, during severe hyperchloremic acidosis, in vitro, in Lipopolysaccharide from E.coli (LPS)-treated J774A.1 murine/macrophage cell line. Our results show that NAC, in hyperchloremic acidosis conditions, reduces nitric oxide (NO) and reactive oxygen species (ROS) release and iNOS expression. Furthermore these effects are associated to alterations in J774A.1 macrophage cell cycle distribution but not to impairments of cell viability and apoptosis induction. Our data report a reduced inflammatory response exerted by NAC in condition of hyperchloremic acidosis indicating that the use of NAC during inflammation further impairs immune response associated to acidosis associated disease, as septic shock
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
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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