Acute appendicitis in infants

Acute appendicitis is very uncommon in the first year of life and often its presentation is atypical with high risk of complications. Hereby, we present 4 clinical cases of infants, who were diag- nosed with acute appendicitis in our hospital over the last year. The reported clinical cases high- light the several drawbacks clinicians face when managing infants with symptoms suggestive for acute appendicitis. After specific diagnostic work-up, even if not conclusive, patients were intra- operatively diagnosed with acute appendicitis and underwent appendicectomy. Maintaining a high index of suspicion for acute appendicitis in infants presenting with intra-abdominal sepsis of unclear etiology is, in our opinion, the most crucial factor to avoid complications and longer hospitalization

3D Localization and Tracking Methods for Multi-Platform Radar Networks

Multi-platform radar networks (MPRNs) are an emerging sensing technology due to their ability to provide improved surveillance capabilities over plain monostatic and bistatic systems. The design of advanced detection, localization, and tracking algorithms for efficient fusion of information obtained through multiple receivers has attracted much attention. However, considerable challenges remain. This article provides an overview on recent unconstrained and constrained localization techniques as well as multitarget tracking (MTT) algorithms tailored to MPRNs. In particular, two data-processing methods are illustrated and explored in detail, one aimed at accomplishing localization tasks the other tracking functions. As to the former, assuming a MPRN with one transmitter and multiple receivers, the angular and range constrained estimator (ARCE) algorithm capitalizes on the knowledge of the transmitter antenna beamwidth. As to the latter, the scalable sum-product algorithm (SPA) based MTT technique is presented. Additionally, a solution to combine ARCE and SPA-based MTT is investigated in order to boost the accuracy of the overall surveillance system. Simulated experiments show the benefit of the combined algorithm in comparison with the conventional baseline SPA-based MTT and the stand-alone ARCE localization, in a 3D sensing scenario

High Pressure Assisted Coronary Stent Implantation Accomplished Without Intravascular Ultrasound Guidance and Subsequent Anticoagulation

AbstractObjectives. The purpose of this study was to determine the efficacy of treatment with antiplatelet therapy and no anticoagulation after high pressure assisted coronary stent implantation performed without intravascular ultrasound (IVUS) guidance.Background. Previous studies have shown that during IVUS-guided Palmaz-Schatz coronary stenting, it is safe to withhold anticoagulation when stent expansion has been optimized by high pressure balloon dilation.Methods. Patients that had successful coronary stenting without IVUS guidance were treated with ticlopidine, 500 mg/day, and aspirin, 325 mg/day, for 1 month and then received only aspirin, 325 mg/day, indefinitely. Patients were not treated with warfarin (Coumadin) or heparin after successful stenting. Clinical and angiographic events were assessed at 1 month.Results. A total of 201 intracoronary stents were implanted in 127 patients with 137 lesions. The average number of stents per lesion was 1.4 ± 0.8, and the average number of stents per patient was 1.6 ± 1.1. Stent deployment was performed for elective indications in 79% of procedures and for emergency indications in 21%. There were four stent thrombosis events for a per patient event rate of 3.1% and a per lesion event rate of 2.9%.Conclusions. After high pressure assisted stenting performed without IVUS guidance, there was an acceptable incidence of 3.1% of stent thrombosis with the combination of short-term ticlopidine and aspirin therapy and no anticoagulation. Although the study involved only 127 patients, the results support the relative safety of stenting without IVUS guidance and with antiplatelet therapy only in comparison to historical trials on stenting performed with postprocedure anticoagulation.(J Am Coll Cardiol 1977;29:21–7)

Quickest Detection and Forecast of Pandemic Outbreaks: Analysis of COVID-19 Waves

The COVID-19 pandemic has, worldwide and up to December 2020, caused over 1.7 million deaths, and put the world's most advanced healthcare systems under heavy stress. In many countries, drastic restriction measures adopted by political authorities, such as national lockdowns, have not prevented the outbreak of new pandemic's waves. In this article, we propose an integrated detection-estimation-forecasting framework that, using publicly available data published by the national authorities, is designed to: (i) learn relevant features of the epidemic (e.g., the infection rate); (ii) detect as quickly as possible the onset (or the termination) of an exponential growth of the contagion; and (iii) reliably forecast the epidemic evolution. The proposed solution is validated by analyzing the COVID-19 second and third waves in the USA.Comment: Submitted to IEEE Communications Magazine, feature topic "Networking Technologies to Combat the COVID-19 Pandemic

siRNAs bearing aromatic residues in the 3’-overhang region

RNA interference (RNAi) is a biological process whereby small interfering RNA (siRNA) and microRNA (miRNA) silence gene expression in a sequence-specific manner. These effectors regulate gene expression through the RNA-induced silencing complex (RISC). It has been suggested that RISC preferentially selects and incorporates one of two strands of the siRNA duplex depending on its thermodynamic features and that the off-target effects of siRNAs can be correlated to the Tm of the duplex. The problem of unwanted incorporation of the passenger strand into RISC could be address altering the thermodynamic asymmetry of the duplex by using specific chemical modifications. Structural studies have revealed that the 3’-overhang region of the guide strand of siRNA is recognized by the PAZ domain and is accommodated into its hydrophobic binding pocket. We expected that aromatic-based modifications in 3’-overhang would enhance RISC selection of antisense strands of siRNA duplexes, reducing off-target effects induced by sense strands. In this study, we report the synthesis of siRNAs bearing diphenylpropylamine, tyramine and tryptamine units at the 3’-end of sense and antisense strands. We found thermodynamic stability of the conjugates was increased by these modifications. Furthermore, but not surprisingly, the modified duplexes were found to retain RNA-like A-type conformation. We also assessed the nuclease resistance of the modified siRNAs and found it was similar to those of unmodified siRNAs. These results prompted us to investigate the silencing activity of the siRNAs possessing the aromatic moiety in the 3’-end by in vitro experiments in mammalian cells

Synthesis, biophysical characterization and anti-HIV activity of d(TG3AG) Quadruplexes bearing hydrophobic tails at the 5'-end

Novel conjugated G-quadruplex-forming d(TG3AG) oligonucleotides, linked to hydrophobic groups through phosphodiester bonds at 50-end, have been synthesized as potential anti-HIV aptamers, via a fully automated, online phosphoramidite-based solid-phase strategy. Conjugated quadruplexes showed pronounced anti-HIV activity with some preference for HIV-1, with inhibitory activity invariably in the low micromolar range. The CD and DSC monitored thermal denaturation studies on the resulting quadruplexes, indicated the insertion of lipophilic residue at the 50-end, conferring always improved stability to the quadruplex complex (20 < DTm < 40 C). The data suggest no direct functional relationship between the thermal stability and anti-HIV activity of the folded conjugated G-quartets. It would appear that the nature of the residue at 50 end of the d(TG3AG) quadruplexes plays an important role in the thermodynamic stabilization but a minor influence on the anti-HIV activity. Moreover, a detailed CD and DSC analyses indicate a monophasic behaviour for sequences I and V, while for ODNs (II–IV) clearly show that these quadruplex structures deviate from simple two-state melting, supporting the hypothesis that intermediate states along the dissociation pathway may exis

Harpin oligonucleotides forming G-quadruplexes: new aptamers with potential anti-HIV activity

Several G-rich synthetic oligodeoxyribonucleotides (ODNs) have shown promising biological properties, ranging from anticancer to anti-HIV activities. G-quadruplex formation was found to be a crucial prerequisite in determining these biological effects. Aptamers exhibiting anti-HIV activity represent an important class of potential therapeutics. Recently we described the synthesis and characterization of new d(TGGGAG) ODNs, conjugated with different aromatic groups at the 5’-end through a phosphodiester bond. The modified sequences showed a parallel stranded tetramolecular G-quadruplexes CD profile and a pronounced anti-HIV-1 activity. Herein, with the aim to use d(TGGGAG) as a lead sequence for a more effective anti-HIV agent, we propose the fully automated synthesis of new ODNs containing two d(TGGGAG) sequences whose 3-ends are joint by an hexaethylenglycole loop. CD analysis was undertaken on the 3’-3’ linked d(TGGGAG) hairpins in comparison with the corresponding unmodified oligomers. Besides, in order to study the influence of the conjugation at the ends of the harpin chains on their ability to stabilize quadruplex structures and on their anti-HIV activity, different conjugated oligomers have been studied

Space-based Global Maritime Surveillance. Part I: Satellite Technologies

Maritime surveillance (MS) is crucial for search and rescue operations, fishery monitoring, pollution control, law enforcement, migration monitoring, and national security policies. Since the early days of seafaring, MS has been a critical task for providing security in human coexistence. Several generations of sensors providing detailed maritime information have become available for large offshore areas in real time: maritime radar sensors in the 1950s and the automatic identification system (AIS) in the 1990s among them. However, ground-based maritime radars and AIS data do not always provide a comprehensive and seamless coverage of the entire maritime space. Therefore, the exploitation of space-based sensor technologies installed on satellites orbiting around the Earth, such as satellite AIS data, synthetic aperture radar, optical sensors, and global navigation satellite systems reflectometry, becomes crucial for MS and to complement the existing terrestrial technologies. In the first part of this work, we provide an overview of the main available space-based sensors technologies and present the advantages and limitations of each technology in the scope of MS. The second part, related to artificial intelligence, signal processing and data fusion techniques, is provided in a companion paper, titled: "Space-based Global Maritime Surveillance. Part II: Artificial Intelligence and Data Fusion Techniques" [1].Comment: This paper has been submitted to IEEE Aerospace and Electronic Systems Magazin

A New Orbiting Deployable System for Small Satellite Observations for Ecology and Earth Observation

In this paper, we present several study cases focused on marine, oceanographic, and atmospheric environments, which would greatly benefit from the use of a deployable system for small satellite observations. As opposed to the large standard ones, small satellites have become an effective and affordable alternative access to space, owing to their lower costs, innovative design and technology, and higher revisiting times, when launched in a constellation configuration. One of the biggest challenges is created by the small satellite instrumentation working in the visible (VIS), infrared (IR), and microwave (MW) spectral ranges, for which the resolution of the acquired data depends on the physical dimension of the telescope and the antenna collecting the signal. In this respect, a deployable payload, fitting the limited size and mass imposed by the small satellite architecture, once unfolded in space, can reach performances similar to those of larger satellites. In this study, we show how ecology and Earth Observations can benefit from data acquired by small satellites, and how they can be further improved thanks to deployable payloads. We focus on DORA—Deployable Optics for Remote sensing Applications—in the VIS to TIR spectral range, and on a planned application in the MW spectral range, and we carry out a radiometric analysis to verify its performances for Earth Observation studies