1,721,021 research outputs found
Power Is Nothing Without Control : The Enduring Search for the Best Cell in Cardiac Cell Therapy at a Crossroads
No full textCardiac cell-based therapy, after a peak of untimely expectations of miraculous efficacy exceeding standard clinical practice, has faced the cardiological community and funding bodies with a predictable trough of disillusionment. In the light of more recent progresses, the field is by contrast moving toward a competitive differentiation phase, in which the resolution of the complex matching between potency of cell therapeutics and heart disease pathophysiology has the potential to make a difference for the most challenging unmet clinical needs in cardiovascular medicine
Logic backbone of a transcription network
No full textA great part of the effort in the study of coarse-grained models of transcription networks concentrates on their dynamical features. In this Letter, we consider their equilibrium properties, showing that the backbone underlying the dynamic descriptions is an optimization problem. It involves N variables, the gene expression levels, and M constraints, the effects of transcriptional regulation. In the case of Boolean variables and constraints, we investigate the structure of the solutions and derive phase diagrams. Notably, the model exhibits a connectivity transition between a regime of simple gene control, where the input genes control O(1) other genes, and a regime of complex control, where some core input genes control O(N) others
Randomization and feedback properties of directed graphs inspired to gene networks
No full textHaving in mind the large-scale analysis of gene regulatory networks, we review a graph decimation algorithm, called “leaf-removal”, which can be used to evaluate the feedback in a random graph ensemble. In doing this, we consider the possibility of analyzing networks where the diagonal of the adjacency matrix is structured, that is, has a fixed number of nonzero entries. We test these ideas on a network model with fixed degree, using both numerical and analytical calculations. Our results are the following. First, the leaf-removal behavior for large system size enables to distinguish between different regimes of feedback. We show their relations and the connection with the onset of complexity in the graph. Second, the influence of the diagonal structure on this behavior can be relevant
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
Emerging treatment options for refractory angina pectoris: Ranolazine, shock wave treatment, and cell-based therapies
No full textA challenge of modern cardiovascular medicine is to find new, effective treatments for patients with refractory angina pectoris, a clinical condition characterized by severe angina despite optimal medical therapy. These patients are not candidates for surgical or percutaneous revascularization. Herein we review the most up-to-date information regarding the modern approach to the patient with refractory angina pectoris, from conventional medical management to new medications and shock wave therapy, focusing on the use of endothelial precursor cells (EPCs) in the treatment of this condition. Clinical limitations of the efficiency of conventional approaches justify the search for new therapeutic options. Regenerative medicine is considered the next step in the evolution of organ replacement therapy. It is driven largely by the same health needs as transplantation and replacement therapies, but it aims further than traditional approaches, such as cell-based therapy. Increasing knowledge of the role of circulating cells derived from bone marrow (EPCs) on cardiovascular homeostasis in physiologic and pathologic conditions has prompted the clinical use of these cells to relieve ischemia. The current state of therapeutic angiogenesis still leaves many questions unanswered. It is of paramount importance that the treatment is delivered safely. Direct intramyocardial and intracoronary administration has demonstrated acceptable safety profiles in early trials, and may represent a major advance over surgical thoracotomy. The combined efforts of bench and clinical researchers will ultimately answer the question of whether cell therapy is a suitable strategy for treatment of patients with refractory angina
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
Ruolo delle cellule staminali di origine midollare CD133+ nella rigenerazione miocardica: dalle evidenze sperimentali ai trial clinici sull’uomo
No full textI recenti progressi delle tecniche di rivascolarizzazione coronarica hanno migliorato il trattamento della cardiopatia ischemica sia nella fase acuta che cronica. Tuttavia, ne è conseguito un aumento di pazienti in una fase avanzata di cardiomiopatia ischemica refrattaria, in cui la terapia medica massimale non sempre permette un controllo completo della sintomatologia o un’efficace riduzione della mortalità associata. Tra le varie possibilità terapeutiche oggetto di ricerca applicata, la terapia cellulare ha mostrato notevoli potenzialità. Sono stati utilizzati numerosi tipi cellulari, tra questi i progenitori endoteliali di origine midollare si collocano tra i più promettenti agenti terapeutici in virtù delle loro proprietà pro-angiogenetiche anti-ischemiche. In particolare, le cellule midollari che esprimono la proteina transmembrana CD133 sono state oggetto di ampi studi sperimentali seguiti da prime applicazioni in clinica negli ultimi anni. Obiettivo di questa rassegna è presentare il processo traslazionale che ha permesso l’applicazione in clinica dei progenitori endoteliali CD133 + nel contesto della cardiomiopatia ischemica.Recent advances in coronary revascularization techniques have improved the outcomes of ischemic heart disease in both acute and chronic settings. As a drawback, an increase in patients with an advanced stage of ischemic cardiomyopathy refractory to optimal medical treatment has been observed. Among the therapeutic alternatives under investigation, cell therapy showed considerable anti-ischemic potential. Although several types of cells have been used, bone marrow-derived endothelial progenitor cells are among the most appealing therapeutic agents due to their angiogenic properties. In particular, endothelial progenitors expressing the transmembrane protein CD133 have been in vitro and in vivo extensively characterized and clinically tested. The aim of this paper is to discuss the translational process that allowed the clinical application of CD133+ endothelial progenitor cells in the context of ischemic cardiomyopathy
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
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