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71.
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Mathematical and computational models are designed to improve our understanding of biological phenomena, to confirm/reject hypotheses, and to find points of intervention by altering the behavior of the studied systems. Here we describe the role of mathematical/computational models of the immune system. In particular, we analyze some examples of how mathematical modeling can contribute to finding optimal vaccination strategies. Indeed, computational modeling offers an intriguing opportunity from the theoretical point of view, and it will be of interest for clinically oriented investigators who wish to find optimal therapeutic strategies and for pharmaceutical industries that want to produce effective and successful drugs. 相似文献
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Filippo Maria Bianchi Simone Scardapane Antonello Rizzi Aurelio Uncini Alireza Sadeghian 《Cognitive computation》2016,8(3):442-461
We propose a system able to synthesize automatically a classification model and a set of interpretable decision rules defined over a set of symbols, corresponding to frequent substructures of the input dataset. Given a preprocessing procedure which maps every input element into a fully labeled graph, the system solves the classification problem in the graph domain. The extracted rules are then able to characterize semantically the classes of the problem at hand. The structured data that we consider in this paper are images coming from classification datasets: they represent an effective proving ground for studying the ability of the system to extract interpretable classification rules. For this particular input domain, the preprocessing procedure is based on a flexible segmentation algorithm whose behavior is defined by a set of parameters. The core inference engine uses a parametric graph edit dissimilarity measure. A genetic algorithm is in charge of selecting suitable values for the parameters, in order to synthesize a classification model based on interpretable rules which maximize the generalization capability of the model. Decision rules are defined over a set of information granules in the graph domain, identified by a frequent substructures miner. We compare the system with two other state-of-the-art graph classifiers, evidencing both its main strengths and limits. 相似文献
75.
Monica Terenziani MD Paolo D'Angelo MD Gianni Bisogno MD Renata Boldrini MD Giovanni Cecchetto MD Paola Collini MD Massimo Conte MD Tina De Laurentis MD Ilaria Ilari MD Paolo Indolfi MD Alessandro Inserra MD Luigi Piva MD Fortunato Siracusa MD Filippo Spreafico MD Paolo Tamaro MD Margherita Lo Curto MD 《Pediatric blood & cancer》2010,54(4):532-537
76.
The scavenger receptor MARCO mediates cytoskeleton rearrangements in dendritic cells and microglia 总被引:7,自引:1,他引:7
Granucci F Petralia F Urbano M Citterio S Di Tota F Santambrogio L Ricciardi-Castagnoli P 《Blood》2003,102(8):2940-2947
Macrophage receptor with collagenous structure (MARCO) is a scavenger receptor expressed in peritoneal macrophages and in a subpopulation of macrophages in the marginal zone of the spleen and in the medullary cord of lymph nodes. By global gene expression analysis, it has been found that the MARCO mRNA was one of the most up-regulated in splenic dendritic cells (DCs) following lipopolysaccharide or bacterial activation and in granulocyte-macrophage colony-stimulating factor (GM-CSF)-treated microglial cells. Here we show that MARCO is expressed on splenic DCs at late time points after activation and that its expression correlates with profound changes in actin cytoskeleton organization in DCs and microglia. During maturation, DCs undergo profound rearrangements of actin cytoskeleton. Immature DCs are adherent with visible actin cables, while fully mature, MARCO-expressing, splenic DCs are nonadherent, round in shape, and have an actin cytoskeleton with a punctate distribution. The simple expression of MARCO was sufficient to induce these cytoskeleton modifications in DCs. MARCO-transfected immature DCs acquired a typical morphology of mature DCs and did not rearrange the actin cytoskeleton following activation. Moreover, DCs in which MARCO was knocked down did not reach the mature phenotype and maintained the typical morphology of transitional DCs. MARCO expression in DCs and microglial cells was also associated with a decrease of antigen internalization capacity. Thus, the MARCO receptor is important for actin cytoskeleton rearrangements and the down-regulation of antigen uptake function during DC and microglial cell maturation. 相似文献
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A Randomized Comparison of Alternative Techniques to Achieve Coronary Sinus Cannulation During Biventricular Implantation Procedures 总被引:1,自引:0,他引:1
Giuseppe De Martino Tommaso Sanna Antonio Dello Russo Gemma Pelargonio Loredana Messano Carolina Ierardi Daniele Gabrielli Quintino Parisi Paolo Zecchi Fulvio Bellocci Filippo Crea 《Journal of interventional cardiac electrophysiology》2004,10(3):227-230
INTRODUCTION: Biventricular pacing system implantation is a time-consuming and challenging procedure. A critical step in biventricular pacemaker implantation is coronary sinus (CS) cannulation. CS cannulation can be achieved either using dedicated guiding catheters (guiding catheter alone positioning strategy, GCA) or with the aid of an electrophysiology catheter advanced inside the guiding catheter (electrophysiology catheter aided positioning strategy, EPA). AIM OF THE STUDY: To evaluate whether the EPA technique is useful for reducing CS cannulation time compared to a conventional GCA technique. METHODS: Thirty-four consecutive patients were randomly assigned to the GCA (18 patients) or EPA (16 patients) CS cannulation strategy. RESULTS: Time to successful catheterization of CS was 5.0 +/- 2.4 min in the EPA group versus 10.1 +/- 5.4 min in the GCA group p = 0.004. Fluoroscopy time was 4.6 +/- 2.3 min in the EPA group versus 9.2 +/- 4.9 min in the GCA group p = 0.004. Total contrast dye volume to search and engage the CS ostium was 0.0 ml in the EPA group versus 14.3 +/- 3.4 ml in the GCA group p < 0.001. CONCLUSIONS: Cannulation of CS with the adjunct of an electrophysiology catheter to dedicated delivery systems significantly reduces procedural time, fluoroscopy time and contrast dye volume compared to a conventional strategy. 相似文献
79.
Gagliardi Federica Lauro Augusto Tripodi Domenico Amabile Maria Ida Palumbo Piergaspare Di Matteo Filippo Maria Palazzini Giorgio Forte Flavio Frattaroli Stefano Khouzam Simone Marino Ignazio R. DAndrea Vito Sorrenti Salvatore Pironi Daniele 《Digestive diseases and sciences》2022,67(3):786-798
Digestive Diseases and Sciences - Mesenteric cysts are defined as a heterogeneous group of intra-abdominal cystic lesions of the mesentery or omentum that may be found in any portion of the... 相似文献
80.
Filippo Gagliardi Alfio Spina Lina Raffaella Barzaghi Michele Bailo Marco Losa Maria Rosa Terreni Pietro Mortini 《Pituitary》2016,19(3):277-285