A highly-detailed anatomical study of left atrial auricle as revealed by in-vivo computed tomography

The left atrial auricle (LAA) is the main source of intracardiac thrombi, which contribute significantly to the total number of stroke cases. It is also considered a major site of origin for atrial fibrillation in patients undergoing ablation procedures. The LAA is known to have a high degree of morphological variability, with shape and structure identified as important contributors to thrombus formation. A detailed understanding of LAA form, dimension, and function is crucial for radiologists, cardiologists, and cardiac surgeons.This review describes the normal anatomy of the LAA as visualized through multiple imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and echocardi-ography. Special emphasis is devoted to a discussion on how the morphological characteristics of the LAA are closely related to the likelihood of developing LAA thrombi, including insights into LAA embryology

Short term outcome of myocarditis and pericarditis following COVID-19 vaccines: a cardiac magnetic resonance imaging study

To evaluate clinical and cardiac magnetic resonance (CMR) short-term follow-up (FU) in patients with vaccine-associated myocarditis, pericarditis or myo-pericarditis (VAMP) following COVID-19 vaccination. We retrospectively analyzed 44 patients (2 women, mean age: 31.7 +/- 15.1 years) with clinical and CMR manifestations of VAMP, recruited from 13 large tertiary national centers. Inclusion criteria were troponin raise, interval between the last vaccination dose and onset of symptoms < 25 days and symptoms-to-CMR < 20 days. 29/44 patients underwent a short-term FU-CMR with a median time of 3.3 months. Ventricular volumes and CMR findings of cardiac injury were collected in all exams. Mean interval between the last vaccination dose and the onset of symptoms was 6.2 +/- 5.6 days. 30/44 patients received a vaccination with Comirnaty, 12/44 with Spikevax, 1/44 with Vaxzevria and 1/44 with Janssen (18 after the first dose of vaccine, 20 after the second and 6 after the "booster" dose). Chest pain was the most frequent symptom (41/44), followed by fever (29/44), myalgia (17/44), dyspnea (13/44) and palpitations (11/44). At baseline, left ventricular ejection fraction (LV-EF) was reduced in 7 patients; wall motion abnormalities have been detected in 10. Myocardial edema was found in 35 (79.5%) and LGE in 40 (90.9%) patients. Clinical FU revealed symptoms persistence in 8/44 patients. At FU-CMR, LV-EF was reduced only in 2 patients, myocardial edema was present in 8/29 patients and LGE in 26/29. VAMPs appear to have a mild clinical presentation, with self-limiting course and resolution of CMR signs of active inflammation at short-term follow-up in most of the cases

Major and trace elements in aerosol of Central Antarctica (Dome C)

La conoscenza della composizione chimica dell'aerosol atmosferico nel continente antartico è essenziale nello studio di cambiamenti climatici avvenuti nell’atmosfera del passato e per stimare i cambiamenti climatici e ambientali attesi in futuro. In questo scenario, l'obiettivo scientifico di questo progetto è stato la determinazione delle concentrazioni di elementi maggiori e in tracce in campioni di aerosol antartico prelevati nel sito remoto di Dome C. Sono stati identificati i livelli di fondo e i trend temporali di questi elementi durante la stagione estiva. Obiettivo ancor più ambizioso è stata l’individuazione di possibili associazioni di elementi, l’identificazione della loro provenienza fino alla loro ripartizione tra le diverse fonti. Si è inoltre indagato l'impatto locale determinato dalle attività della stazione scientifica. Per l'analisi dei dati sono state impiegate tecniche di statistica multivariata, supportate nell’interpretazione dei risultati, dall’analisi della direzione del vento prevalente, dalle retrotraiettorie delle masse d'aria pervenute al sito di campionamento e dai fattori di arricchimento crostale e marino. Le elaborazioni statistiche hanno mostrato un buon accordo tra loro e hanno evidenziato tre principali gruppi di elementi (marino, crostale e antropico), concentrati attorno a traccianti riconosciuti. I risultati hanno evidenziato un inquinamento generalizzato nella prima parte della stagione, in particolare in prossimità della base. Elementi di origine naturali hanno caratterizzato in prevalenza i campioni raccolti presso la Tenda Astrofisica, dove la concentrazione atmosferica di aerosol è influenzata soprattutto dalle masse d'aria provenienti da siti remoti. Questo progetto ha aperto nuove prospettive nella comprensione della composizione dell’aerosol antartico per quanto riguarda gli elementi maggiori e in tracce, trovando associazioni di elementi derivanti da fonti locali o remote. Questo aspetto è da considerarsi un contributo fondamentale alla conoscenza della circolazione atmosferica globale, nella prospettiva di stimare i cambiamenti climatici e ambientali attesi per il futuro.The knowledge of the chemical composition of the atmospheric aerosol in the Antarctic continent is essential to reconstruct the changes that occurred in the terrestrial atmosphere in the past, and at estimating the climatic and environmental changes expected for the future. In this scenario, the scientific objective of this project was to determine, for the first time in aerosol samples collected at Dome C, Antarctic plateau, the concentrations of major and trace elements. Moreover, the work was addressed at identifying their background levels and assessing temporal trends of these elements during the summer season. The study was also addressed at investigating the local impact generated directly by the scientific station activities and further ambitious targets of the research were to detect possible element associations and to infer, for each element/group of elements, on their main sources, and even their apportionment between the different sources. Advanced multivariate statistical techniques have been used for data analysis and further support tools have been employed for data interpretation: the analysis of local prevailing wind direction, the pathway of air masses coming to the sampling site from remote areas and the crustal and marine enrichment factors. Advanced statistical elaborations showed a good agreement and highlighted three groupings of elements, clustered around recognized marine, crustal and anthropic tracers. Results underline a general high pollution in the first part of the season, particularly in the proximity of the station, with decreasing level during the entire sampling period. Natural factors prevail in samples collected at the Astrophysic Tent, where aerosol atmospheric concentration is influenced also by air masses coming from remote sites. This Ph.D. project has opened new perspectives in understanding the major and trace element composition of the aerosol collected at the Antarctic Plateau, finding element associations deriving from either local or remote sources, reaching the most pristine area of the Planet. This aspect is considered fundamental, contributing to the knowledge of the atmospheric global circulation, in the view of estimating the climatic and environmental changes expected for the future

Determination of water-soluble, acid-extractable and inert fractions of Cd, Pb and Cu in Antarctic aerosol by square wave anodic stripping voltammetry after sequential extraction and microwave digestion

A two-step microwave (MW) digestion (ramps to 135 °C and to 185 °C) was set up for the subsequent voltammetric determination of the inert fraction of Cd, Pb and Cu in Antarctic aerosol (PM10), after a sequential extraction with water (soluble fraction) and dilute HCl (acid extractable fraction) of the filter samples. A digestion mixture of 5.0 mL HNO3, 1.0 mL H2O2, and 1.0 mL HF was used. The amount of H2O2 was adjusted at a compromise value to avoid interferences from organic substances or fromthe reagent itself. Hydrogen fluoride was used at the maximum quantity suggested in the literature, since there were no interferences due to excess HF with the voltammetric measurement. Our procedure did not provide for a third digestion step with H3BO3, as generally required in order to eliminate excess HFwhen subsequent spectrochemical analyses are to be carried out. Thus the total digestion time was reduced from ~5 h to ~1.5 h. The ultrasensitive technique of square wave anodic stripping voltammetry (SWASV) was used and optimized by maximizing the signal-to-noise ratio (frequency 150 Hz, amplitude 20 mV). The limits of detection (e.g. for atmospheric concentration 0.1–0.3 pg m−3 for Cd and 1–5 pg m−3 for Pb and Cu) and the repeatabilities (Cd 21–26%, Pb 16–20%, Cu 11–14% as atmospheric concentration) compared favourably with literature reports. Significant aliquots of metals were present in all the three fractions determined and the inert fraction represented 20–74% for Cd, 10–63% for Pb, and 7–33% for Cu, against total contents of Cd 1–19 pg m−3, Pb 17–36 pg m−3, and Cu 177–429 pg m−3. Possibly significant metal fractions could be associated to the crustal origin

Evolution of size-segregated aerosol mass concentration during the Antarctic summer at Northern Foothills, Victoria Land

Within the framework of the Italian National Programm for Antarctic Research (PNRA), the first direct gravimetric measurements of size-segregated aerosol fractions were carried out at Faraglione Camp, ~3- km far from the Italian station “M. Zucchelli” (Terra Nova Bay, Ross Sea), during the 2014e2015 austral summer. A six-stage high-volume cascade impactor with size classes between 10 mm and 0.49 mm, and, in parallel, for comparison purposes, a PM10 high-volume sampler (50% cut-off aerodynamic diameter of 10 mm) were used. A 10-day sampling strategy was adopted. Aerosol mass measurements were carried out before and after exposure by using a microbalance specifically designed for the filter weight and placed inside a glove bag in order to maintain stable temperature and humidity conditions during weighing sessions. Measured atmospheric concentrations (referred to the “actual air conditions” of mean temperature of 268 K and mean pressure of 975 hPa) of size-segregated aerosol fractions showed the following values, given as size range, means (interquartile range): Dp < 0.49 mm, 0.33 (0.26e0.34) mgm3; 0.49e0.95 mm, 0.20 (0.19e0.24) mgm3; 0.95e1.5 mm, 0.16 (0.13e0.21) mgm3; 1.5e3.0 mm 0.075 (0.05e0.11) mg m3; 3.0e7.2 mm 0.12 (0.02e0.19) mg m3; 7.2e10 mm 0.06 (0.01e0.03) mg m3. The average mass concentration of the total PM10 at Faraglione Camp for the entire sampling period was 0.92 (0.67e1.1) mg m3. Although a great variability, the aerosol mass concentration showed a tri-modal distribution, with an accumulation mode (in the range 0.1e1.0 mm) and two coarse modes (CM1 in the range 1.0e3.0 mm, and CM2 in the range 3.0e10 mm). From 50% to 90% of the PM10 mass comes from particles of a size smaller than 1.0 mm. The two coarse modes represented from ~5% to ~35% of the PM10, showing opposite seasonal trends (CM1 decreased while CM2 increased). During summer, PM10 mass concentration increased to a maximum of ~1.6 mg m3 at mid-December, while in January it decreased to values that are typical of November. Both accumulation and upper super-micron fractions showed a maximum in the same period contributing to the PM10 peak of mid-summer