1,721,121 research outputs found
Synthesis of the Data on COVID-19 Skin Manifestations: Underlying Mechanisms and Potential Outcomes
Full text linkThe incidence of coronavirus disease 2019 (COVID-19)-related skin manifestations has progressively grown, in parallel with the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreading. The available evidence indicates that cutaneous signs are heterogeneous and can be divided as follows: a) erythematous rashes, b) lesions of vascular origin, c) vesicular rashes, d) urticarial rashes, and e) acute generalized exanthematous pustulosis (AGEP), erythema multiforme (EM) and other polymorphic/atypical reactions. Most cutaneous manifestations appear simultaneously or after respiratory and/or systemic symptoms such as fever, even if rarely urticaria has been reported as the first sign of the disease. It has been proposed that erythematous and vesicular rashes, as well as urticaria, are the result of immunological activation against Sars-CoV-2, similarly to other viral exanthems; alternatively, reactivation or co-infection of herpesviruses and drug hypersensitivity represent possible etiologic diagnosis that has to be considered. Regarding lesions of vascular origin, ischemic ones are the result of systemic hypercoagulability established in severe infections, whereas chilblains seem to be linked to the type I-interferon massively produced to halt virus replication. AGEP is triggered by drugs, whereas EM could represent a delayed immune response to the virus or a hypersensitivity reaction to drugs elicited by the inflammatory process built to fight the infection. A further pathogenic hypothesis is that the virus, or its particles detected in the skin (particularly in endothelium and eccrine glands), could be responsible for certain skin reactions, including chilblains and EM. From the available data, it appears that chilblains are correlated with younger age and less severe disease, while ischemic manifestations occur in the elderly with severe infection. In conclusion, larger studies are needed to confirm the suggested pathogenetic mechanisms of COVID-19-related skin reactions and to determine the potential prognostic significance of each one
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
Suitability of different multi-functionalized nanocarriers aimed to address antigen presenting cells for vaccination purposes, and parameters that regulate unwanted accumulation of nanocarriers in the liver
No full textThe treatment of severe immune diseases such as cancer, allergy or autoimmunity demands new strategies to overcome the development of resistances or relapses. The employment of nanoparticles as carriers for the delivery of biological components targeting specific tissues or cell types might help to meet these challenges. Especially their employment for the vaccination of antigen presenting cells (APCs), a pivotal group of immune cells, has turned out to be a promising immunotherapeutic approach. In this case, nanocarriers ensure the co-delivery of antigen and adjuvant, the two components required for a vaccination.
The aim of this thesis was to investigate the potential of different types of nanoparticles for an in situ vaccination of APCs to induce an effective immune response. Therefore, inorganic and organic, polymer-based non-toxic nanoparticles were synthesized, and modified with various biological components with the aim to target and activate APCs. These nanocarriers were investigated in cell cultures and mouse models regarding their biodistribution, APC targeting efficiency and their capacity to induce T cell immune responses.
To achieve an active targeting of APCs their expression of C-type lectins which constitute pathogen recognizing receptors, were exploited. Natural ligands for these receptors or corresponding antibodies were attached to the nanocarriers which led to a successful targeting of dendritic cells and B cells in vitro and in vivo, as confirmed by flow cytometry and confocal microscopy. Comprehensive biodistribution experiments of sarcosine-based polymer brushes on organ and cellular level provided more insights into mechanisms leading to liver trapping of nanoparticles, which is often observed after their systemic application.
This study revealed that antibody-coated polymer-brushes are cleared by Fc (fragment
crystallizable) receptors of liver sinusoidal endothelial cells and indicated that a lower antibody density on nanocarriers is preferable since this largely prevented their recognition by Fc receptors compared to high antibody amounts, and thereby facilitated the intended dendritic cell (DC)-specific targeting.
Functionalization of the nanocarriers with a toll-like receptor (TLR) ligand or nucleotide binding oligomerization domain (NOD)-like receptor (NLR) ligand as an adjuvant and SIINFEKL/Ovalbumin (OVA), a protein derived from the chicken egg as model antigen led to a maturation of targeted dendritic cells in vitro and induced a T cell response in vitro and in vivo. Finally, the efficiency of this approach was confirmed in tumor and allergy mouse models. To conclude, the obtained results indicate a functional activity of different nanocarriers, give new insights into the requirements for a nanoparticle-based APC vaccination and show that these can be fulfilled by several types of nanoparticles.Getrennte Zählungen ; Illustrationen, Diagramm
Retrospektive Analyse zum Outcome spinozellulärer Karzinome unter Berücksichtigung tumorspezifischer Kriterien
Full text linkVIII, 99 Seiten ; Diagramm
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
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