Relevance of temporal cores for epidemic spread in temporal networks.

Temporal networks are widely used to represent a vast diversity of systems, including in particular social interactions, and the spreading processes unfolding on top of them. The identification of structures playing important roles in such processes remains largely an open question, despite recent progresses in the case of static networks. Here, we consider as candidate structures the recently introduced concept of span-cores: the span-cores decompose a temporal network into subgraphs of controlled duration and increasing connectivity, generalizing the core-decomposition of static graphs. To assess the relevance of such structures, we explore the effectiveness of strategies aimed either at containing or maximizing the impact of a spread, based respectively on removing span-cores of high cohesiveness or duration to decrease the epidemic risk, or on seeding the process from such structures. The effectiveness of such strategies is assessed in a variety of empirical data sets and compared to baselines that use only static information on the centrality of nodes and static concepts of coreness, as well as to a baseline based on a temporal centrality measure. Our results show that the most stable and cohesive temporal cores play indeed an important role in epidemic processes on temporal networks, and that their nodes are likely to include influential spreaders.

Action potential-based MEA platform for in vitro screening of drug-induced cardiotoxicity using human iPSCs and rat neonatal myocytes.

Drug-induced cardiotoxicity poses a negative impact on public health and drug development. Cardiac safety pharmacology issues urged for the preclinical assessment of drug-induced ventricular arrhythmia leading to the design of several in vitro electrophysiological screening assays. In general, patch clamp systems allow for intracellular recordings, while multi-electrode array (MEA) technology detect extracellular activity. Here, we demonstrate a complementary metal oxide semiconductor (CMOS)-based MEA system as a reliable platform for non-invasive, long-term intracellular recording of cardiac action potentials at high resolution. Quinidine (8 concentrations from 10-7 to 2.10-5M) and verapamil (7 concentrations from 10-11 to 10-5M) were tested for dose-dependent responses in a network of cardiomyocytes. Electrophysiological parameters, such as the action potential duration (APD), rates of depolarization and repolarization and beating frequency were assessed. In hiPSC, quinidine prolonged APD with EC50 of 2.2·10-6M. Further analysis indicated a multifactorial action potential prolongation by quinidine: (1) decreasing fast repolarization with IC50 of 1.1·10-6M; (2) reducing maximum upstroke velocity with IC50 of 2.6·10-6M; and (3) suppressing spontaneous activity with EC50 of 3.8·10-6M. In rat neonatal cardiomyocytes, verapamil blocked spontaneous activity with EC50 of 5.3·10-8M and prolonged the APD with EC50 of 2.5·10-8M. Verapamil reduced rates of fast depolarization and repolarization with IC50s of 1.8 and 2.2·10-7M, respectively. In conclusion, the proposed action potential-based MEA platform offers high quality and stable long-term recordings with high information content allowing to characterize multi-ion channel blocking drugs. We anticipate application of the system as a screening platform to efficiently and cost-effectively test drugs for cardiac safety.

An innovative fast track solution for food bolus impaction due to Jackhammer esophagus in an emergency department: the "Nitro-Push Blind Technique" case report.

BACKGROUND: In the medical literature are described only few clinical cases of esophageal food bolus impaction due to esophageal motility disorders. Moreover, the management of this condition is highly variable with no evidence in the literature to strongly support a clear defined intervention. CASE PRESENTATION: In this paper we describe for the first time a case of 53-year-old male with food bolus impaction due to Jackhammer esophagus referred to emergency department. On the basis of the known esophageal past medical history as well as the absence of bones in the bolus, the patient was submitted to a new conservative treatment, the "Nitro-Push Blind Technique". CONCLUSIONS: The new technique performed with naso-gastric tube thrust after nitrates medication in definite clinical case supported by known functional disease, represents a safe and successful method, with short observational period to minimize exposure to potential morbidity and reduce the inpatient stay in emergency department. It should be recommended, once validated in a larger cohort, as the initial treatment of choice in the selected patients with food boneless bolus impaction in the emergency settings. Indeed, this management provides only minimal deviation from the current practice and is hence technically easy to learn and perform.

Hepatic steatosis, carotid atherosclerosis and metabolic syndrome: the STEATO Study.

PURPOSE: Hepatic steatosis is frequently observed in subjects with metabolic syndrome (MS). In type 2 diabetics, it is independently associated with cardiovascular diseases. In order to confirm and extend this finding, a large group of patients with risk factors for atherosclerosis was studied. METHODS: Carotid atherosclerosis was investigated by echo-Doppler, and hepatic steatosis by ultrasound and transaminase values. Strict exclusion criteria were chosen in order to avoid secondary forms of fatty liver and interference on transaminase values. RESULTS: Among 970 enrolled patients, about 20% were diabetics, half had MS and 76% presented echographic hepatic steatosis. In multivariate analyses, fatty liver and MS were associated with carotid atherosclerosis [odds ratio (95% confidence intervals) 2.15 (1.27-3.63) and 1.72(1.12-2.64), respectively], whereas HOMA index was not. Aspartate aminotransferase and alanine aminotransferase were not independently associated with carotid atherosclerosis, whereas gamma-glutamyl transferase showed a link with atherosclerosis beyond MS and steatosis presence. The analyses of the 780 non diabetics recruited showed similar results. CONCLUSIONS: The results of the present study demonstrate that hepatic steatosis measured by echography is associated with carotid atherosclerosis in a large population mostly carrying cardiovascular or metabolic risk factors, independently of MS, cardiovascular diseases, diabetes mellitus and/or insulin resistance.

MaSDA: a system for analyzing mass spectrometry data.

Mass spectrometry (MS) approaches have been recently coupled with advanced data analysis techniques in order to enable clinicians to discover useful knowledge from MS data. However, effectively and efficiently handling and analyzing MS data requires to take into account a number of issues. In particular, the huge dimensionality and the variety of noisy factors present in MS data require careful preprocessing and modeling phases in order to make them amenable to the further analysis. In this paper we present MaSDA, a system performing advanced analysis on MS data. MaSDA has the following main features: (i) it implements an approach of MS data representation that exploits a model based on low dimensional, dense time series; (ii) it provides a wide set of MS preprocessing operations which are accomplished by means of a user-friendly graphical tool; (iii) it embeds a number of tools implementing various tasks of data mining and knowledge discovery, in order to assist the user in taking critical clinical decisions. Our system has been experimentally tested on several publicly available datasets, showing effectiveness and efficiency in supporting advanced analysis of MS data.