1,721,455 research outputs found

    Three dimensional oral mucosa models: development and applications

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    Animal experimentation has been extensively and for a long time applied in several research fields, but since 2011 it has been substantially limited by the Commission of the European Parliament to ensure people/animals safety and reduce research costs. To respond to these directives, many attempts have been focused on the development and validation of new in vitro 3D systems, bypassing the traditional 2D cell cultures. In this regard, diverse approaches to tissue-engineered bone and oral mucosa have been developed. Despite the promising premises and the cutting-edge results, the used 3D in vitro bone-oral mucosal models still lack interaction between the mucosal and the bone components. Therefore, this project aimed to create 3D models, entirely made with primary human cells (keratinocytes, fibroblasts, and osteoblasts), able to mimic the natural structure and interaction of bone and oral mucosa. In the present work, the regulatory role of the mesenchymal tissue onto epithelia was evaluated. The main results showed that that during the differentiation hMSC produce and secrete factors that induce the keratinization and the expression of the marker of differentiation CK10; in particular in the middle stage of differentiation (OB14). The proteomic analysis revealed that this effect can be ascribable to KGF secretion. This finding may impact the design of new implantable devices able to induce, alone, the epithelial growth and keratinization to improve implant graft avoiding epithelial graft linked to the morbidity of another zone. Moreover, we also showed that OM might have a pro-innervation effect, at least during the last stages of keratinocytes stratification. Finally, we obtained and characterized an innervated mucoperiosteal model that could open new in vitro frontiers for oral biomaterials validation as well as improve knowledge regarding the mesenchymal stem cells roles onto oral mucosa development

    High-risk HPVs, microbiota and epithelial carcinogenesis: state of the art and research contribution of in vitro 3D models

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    Persistent high-risk human papillomavirus (HR-HPV) infection is associated with anogenital and head & neck squamous epithelial (HNSCC) tumors, which altogether cause about 550,000 new cases every year. Several evidences suggest that the microbiota could have a role on the inflammatory, epithelial mesenchymal transition and tumorigenesis processes promoted by HR-HPV infection, yet the mechanisms involved remain to be clarified. In this review we report the state of the art on this topic and on the most promising in vitro developed models for studying the host-pathogen interactions. Using MEDLINE, several terms were searched and combined to select the most pertinent papers. The investigation was limited to the international indexed articles published in PubMed in the last 10 years. This review reports the latest knowledge in the field of the microbial-associated anogenital tumors and HNSCC. In addition, we also discuss the in vitro epithelial culture systems that reproduce the pathophysiological features of the tumoral microenvironment and the in vivo response to microbial agents, thus representing a useful tool for analyzing at cellular and molecular levels the role played by infective agents in tumorigenesis

    Polyphenols and bioactive glass: a smart couple against cancer

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    Polyphenols are natural molecules with selective cytotoxic activity against cancer cells and, on the opposite, stimulating activity on healthy ones . Poor bioavailability and stability are actually their main drawbacks for their application in the medical field but there are key points for the improvement of their effectiveness. Surface functionalization is a promising strategy to combine the properties of biomaterials with those of polyphenols in order to guarantee an adequate amount of active molecules at the desired site. Bioactive glasses are materials of choice for bone contact applications due to their ability to chemically bind to bone and stimulate its regeneration. In this research work a silica based bioactive glass (CEL2) [3] was used as substrate and gallic acid (GA), as model molecule and natural extracts of green tea leaves (TPH) and red grape skins (GPH) as natural polyphenols for the surface functionalization. The grafting procedure was optimized in previous works of the author

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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