1,721,073 research outputs found
Adult stem cells and skeletal muscle regeneration
Full text linkSatellite cells are unipotent stem cells involved in muscle regeneration. However, the skeletal muscle microenvironment exerts a dominant influence over stem cell function. The cell intrinsic complexity of the skeletal muscle niche located within the connective tissue between fibres includes motor neurons, tendons, blood vessels, immune response mediators and interstitial cells. All these cell types modulate the trafficking of stimuli responsible of muscle fibre regeneration. In addition, several types of stem cell have been discovered in skeletal muscle tissue, mainly located in the interstitium. The majority of these stem cells appear to directly contribute to myogenic differentiation, although some are mainly implicated in paracrine effects. This review focuses on one of these classes of stem cells known as adult stem cells, which following their identification in the last decade have been used for therapeutic purposes, mainly in animal models of chronic muscle degeneration. Emerging literature identifies other myogenic progenitors generated from pluripotent stem cells as potential candidates for the treatment of skeletal muscle degeneration. However, adult stem cells still represent the gold standard for future comparative studies.sponsorship: We would like to apologize to all authors whose work has not been reported here due to space limitations. This work has been supported with the contribution of "Opening The Future" Campaign (EJJ-OPTFUT-02010), CARE-MI FP7, AFM Telethon, CARIPLO, FWO (#G060612N, #G0A8813N, #G088715N), GOA, IUAP and OT grants. EB is supported by FWO Postdoctoral Fellowship (12D2813N) and FWO grant (1525315N). DC is supported by University of Turin ("Assegni cofinanziati per la collaborazione ad attivita e ricerca"). We thank Christina Vochten and Vicky Raets for professional administrative assistance. We would also like to thank Rondoufonds voor Duchenne Onderzoek for kind donations. Finally, we are particularly grateful to Professor Llewelyn Roderick for critical reading and helpful editing of the manuscript. (FWO Postdoctoral Fellowship|12D2813N, FWO|1525315N, FWO|G060612N, FWO|G0A8813N, FWO|G088715N, University of Turin, "Opening The Future" Campaign|EJJ-OPTFUT-02010, CARE-MI FP7, AFM Telethon, CARIPLO, GOA, IUAP, OT)status: Publishe
3D bioprinting and Rigenera® micrografting technology: A possible countermeasure for wound healing in spaceflight
Full text linkPlant and animal life forms have progressively developed mechanisms for perceiving and responding to gravity on Earth, where homeostatic mechanisms require feedback. Lack of gravity, as in the International Space Station (ISS), induces acute intra-generational changes in the quality of life. These include reduced bone calcium levels and muscle tone, provoking skin deterioration. All these problems reduce the work efficiency and quality of life of humans not only during exposure to microgravity (mu G) but also after returning to Earth. This article discusses forthcoming experiments required under gravity and mu G conditions to ensure effective and successful medical treatments for astronauts during long-term space missions, where healthcare is difficult and not guaranteed
Adult Stem Cells and Skeletal Muscle Regeneration
No full textSatellite cells are unipotent stem cells involved in muscle regeneration. However, the skeletal muscle microenvironment exerts a dominant influence over stem cell function. The cell intrinsic complexity of the skeletal muscle niche located within the connective tissue between fibers includes motor neurons, tendons, blood vessels, immune response mediators and interstitial cells. All these cell types modulate the trafficking of stimuli responsible of muscle fiber regeneration. In addition, several stem cell types have been discovered in skeletal muscle tissue, mainly located in the interstitium. The majority of these stem cells appears to directly contribute to myogenic differentiation, although some of them are mainly implicated in paracrine effects. This review focuses on adult stem cells, which have been used for therapeutic purposes, mainly in animal models of chronic muscle degeneration. Emerging literature identifies other myogenic progenitors generated from pluripotent stem cells as potential candidates for the treatment of skeletal muscle degeneration. However, adult stem cells still represent the gold standard for future comparative studies
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
Effects of substrates nanopattering on osteosarcoma cell behaviour.
No full textEngineering of the cellular microenvironment has become an attractive strategy to guide cellular activities such as spreading, motility, proliferation and differentiation. From a technological perspective, the physical crosstalk between the cell and its surroundings represents a design parameter that may be modulated to achieve desired physiological outcome. In this study we present a surface engineering approach to tap into the physical crosstalk between the cell and its surroundings in order to modulate osteogenic anchorage-dependent differentiation and bone formation. The effectiveness of this approach was studied by comparing the cellular behavior of human SOAS sarcoma cells on nanostructured silicon substrates with distinct nanoscale patterns.
Random nano-islands were realized by controlled deposition of tin on the polished side of silicon wafers by thermal evaporation. Four different shaped surfaces of nano structured substrates were used in this study. Silicon substrates present surface islands with diameters ranging from 10 to 35 nm and inter-island distances of 41 (B), 51 (E) or 80 (F) nm respectively. Substrate A is planar silicon used as contro
- …
