9 research outputs found

    DESIGN OF SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY

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    openPresentation on the state of the art of optical coherence tomography (OCT) and design of a tomograph based on a swept-type laser source centered at 1305 nm

    Overview on electrical issues faced during the SPIDER experimental campaigns

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    SPIDER is the full-scale prototype of the ion source of the ITER Heating Neutral Beam Injector, where negative ions of Hydrogen or Deuterium are produced by a RF generated plasma and accelerated with a set of grids up to ~100 keV. The Power Supply System is composed of high voltage dc power supplies capable of handling frequent grid breakdowns, high current dc generators for the magnetic filter field and RF generators for the plasma generation. During the first 3 years of SPIDER operation different electrical issues were discovered, understood and addressed thanks to deep analyses of the experimental results supported by modelling activities. The paper gives an overview on the observed phenomena and relevant analyses to understand them, on the effectiveness of the short-term modifications provided to SPIDER to face the encountered issues and on the design principle of long-term solutions to be introduced during the currently ongoing long shutdown.Comment: 8 pages, 12 figures. Presented at SOFT 202

    Ultra-rapid debinding and sintering of additively manufactured ceramics by ultrafast high-temperature sintering

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    International audienceIn recent years, additive manufacturing (AM) of ceramics has significantly advanced in terms of the range of equipment available, printing resolution and productivity. Most techniques involve the use of ceramic powders embedded in an organic binder which is typically removed through a slow thermal debinding process. Herein, we prove for the first time that ultra-rapid debinding and sintering are possible for complex 3YSZ components produced using material extrusion technology. The printed components were first chemically debinded in acetone thus removing about one-half of the binder, and then thermally debinded and sintered by ultrafast high-temperature sintering (UHS) in a single-step process (30 to 120s). Fully dense components were obtained with tailored microstructure and nanometric grain size. The sintered artefacts were crack-free even at the microscopic level. This approach paves the way for rapid processing (debinding and sintering) of additively manufactured ceramics with reduced energy consumption and carbon footprint

    Reversibility of Frail Phenotype in Patients with Inflammatory Bowel Diseases

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    It was recently reported that frailty status can negatively influence the clinical course of patients with inflammatory bowel diseases (IBDs). Our recent study demonstrated that 20% of patients with an IBD are frail, and disease activity increases the risk of frailty. In the present study, we prospectively monitored this subgroup of frail patients, assessed whether the frailty status was reversible, and analyzed factors associated with frailty reversibility. Of the sixty-four frail patients with IBD enrolled, five (8%) were lost during the follow-up period and one (2%) underwent a colectomy. Eleven out of the fifty-eight (19%) patients maintained a frail phenotype during a median follow-up of 8 months (range 6–19 months), and thirty-five (60%) and twelve (21%) became pre-frail or fit, respectively. A comparison of the 58 patients at baseline and at the end of the study showed that frail phenotype reversibility occurred more frequently in patients who achieved clinical remission. A multivariate analysis showed that the improvement of the frail phenotype was inversely correlated with the persistence of clinically active disease (OR:0.1; 95% CI: 0.02–0.8) and a history of extra-intestinal manifestations (OR:0.1; 95% CI: 0.01–0.6) and positively correlated with the use of biologics (OR: 21.7; 95% CI: 3.4–263). Data indicate that the frail phenotype is a reversible condition in most IBD patients, and such a change relies on the improvement in disease activity

    Twenty-Five Year Multicentre Experience of Explantation of Infected Abdominal Aortic Endografts

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    : We report a multicenter experience of open conversions (OC) for aortic endograft infections (AEI). We retrospectively analyzed all patients who underwent OC for AEI after endovascular aneurysm repair (EVAR), from 1997 to 2021 in 12 Italian centers. The endpoints were as follows: mortality (30-days, in-hospital), major postoperative complications. Follow-up data included: survival, aortic-related complications, infection persistence or reoccurrence. Fifty-eight patients (mean age: 73.8 ± 6.6 years) were included. Median time from EVAR to OC was 14 months (interquartile range 7-45). Thirty-five patients (60.3%) were symptomatic at presentation. Aortic reconstruction was anatomic in 32 patients (55.2%), extra-anatomic in 26 (44.8%). Thirty-day mortality was 31% (18/58). Six additional patients died after 30 days during the same hospitalization (in-hospital mortality: 41.4%). Most common post-operative complications included respiratory failure (38.6%) and renal insufficiency (35.1%). During 28.1 ± 4 months follow-up, 4 aneurysm-related deaths were recorded. Infection re-occurred in 29.4% of the patients. Estimated survival was 50% at 1 year, and 30% at 5 years, and was significantly lower for patients who underwent extra-anatomic reconstructions (37 vs 61% at 1 year, 16 vs 45% at 5 years; log-rank P = .021). OC for AEI is associated with high early mortality. The poor mid-term survival is influenced by aortic complications and infection re-occurrence

    Lactoferrin Against SARS-CoV-2: In Vitro and In Silico Evidences

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    Lactoferrin (Lf) is a cationic glycoprotein synthetized by exocrine glands and is present in all human secretions. It is also secreted by neutrophils in infection and inflammation sites. This glycoprotein possesses antimicrobial activity due to its capability to chelate two ferric ions per molecule, as well as to interact with bacterial and viral anionic surface components. The cationic features of Lf bind to cells, protecting the host from bacterial and viral injuries. Its anti-inflammatory activity is mediated by the ability to enter inside the nucleus of host cells, thus inhibiting the synthesis of proinflammatory cytokine genes. In particular, Lf down-regulates the synthesis of IL-6, which is involved in iron homeostasis disorders and leads to intracellular iron overload, favoring viral replication and infection. The well-known antiviral activity of Lf has been demonstrated against DNA, RNA, and enveloped and naked viruses and, therefore, Lf could be efficient in counteracting also SARS-CoV-2 infection. For this purpose, we performed in vitro assays, proving that Lf exerts an antiviral activity against SARS-COV-2 through direct attachment to both SARS-CoV-2 and cell surface components. This activity varied according to concentration (100/500 mu g/ml), multiplicity of infection (0.1/0.01), and cell type (Vero E6/Caco-2 cells). Interestingly, the in silico results strongly supported the hypothesis of a direct recognition between Lf and the spike S glycoprotein, which can thus hinder viral entry into the cells. These in vitro observations led us to speculate a potential supplementary role of Lf in the management of COVID-19 patients

    Multicentre comparison between open conversions and semi-conversions for late endoleaks after EVAR

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    Objective: The aim of this study is to compare early and follow-up outcomes of late open conversions (LOC, with complete or partial endograft explantation) and semi-conversions (SC, with endograft preservation) after endovascular aneurysm repair in a multicenter experience. Methods: All LOC and SC performed from 1997 to 2020 in 11 vascular centers were compared. Endograft infections or thrombosis were excluded. Primary endpoints were early mortality and long-term survival estimates. Secondary endpoints were differences in postoperative complication rates and conversion-related complications during follow-up. Results: In the considered period, 347 patients underwent surgery for endovascular aneurysm repair complications. Among these, 270 were operated on for endoleaks (222 LOC, 48 SC). The two groups were homogeneous in terms of American Society of Anesthesiologists score (LOC, 3.2 ± 0.7; SC, 3 ± 0.5; P = .128) and main endograft characteristics (suprarenal fixation, bifurcated/aorto-uni-iliac configuration). The mean age was 75 ± 8 years for LOC and 79 ± 7 years for SC (P = .009). Reasons for LOC were: 62.2% (138/222) type I endoleak, 21.6% (48/222) type II endoleak, 7.7% (17/222) type III endoleak, and 8.5% (19/222) endotension. Indications for SC were: 64.6% (31/48) type II endoleak, 33.3% (16/48) type I endoleak, and 2.1% (1/48) type III endoleak. Thirty-day mortality was 12.2% (27/222) in the LOC group, and 10.4% (5/48) in the SC group (P = .73). Postoperative complication rate was higher in the LOC group (45.5% vs 29.2%; P = .04). The estimated survival rate after LOC was 80% at 1 year and 64% at 5 years; after SC, it was 72% at 1 year and 37% at 5 years (log-rank P = .01). During the median follow-up of 21.5 months (interquartile range, 2.4-61 months), an endoleak after SC was found in the 38.3% of the cases; sac growth was recorded in the 27.7% of SC patients. Conclusions: SC has an early benefit over LOC in terms of reduced postoperative complications but has a significantly inferior mid-term survival. The high rates of persistent and/or recurrent endoleaks reduce SC durability

    Lactoferrin as Antiviral Treatment in COVID-19 Management: Preliminary Evidence

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    Lactoferrin (Lf), a multifunctional cationic glycoprotein synthesized by exocrine glands and neutrophils, possesses an in vitro antiviral activity against SARS-CoV-2. Thus, we conducted an in vivo preliminary study to investigate the antiviral effect of oral and intranasal liposomal bovine Lf (bLf) in asymptomatic and mild-to-moderate COVID-19 patients. From April 2020 to June 2020, a total of 92 mild-to-moderate (67/92) and asymptomatic (25/92) COVID-19 patients were recruited and divided into three groups. Thirty-two patients (14 hospitalized and 18 in home-based isolation) received only oral and intranasal liposomal bLf; 32 hospitalized patients were treated only with standard of care (SOC) treatment; and 28, in home-based isolation, did not take any medication. Furthermore, 32 COVID-19 negative, untreated, healthy subjects were added for ancillary analysis. Liposomal bLf-treated COVID-19 patients obtained an earlier and significant (p < 0.0001) SARS-CoV-2 RNA negative conversion compared to the SOC-treated and untreated COVID-19 patients (14.25 vs. 27.13 vs. 32.61 days, respectively). Liposomal bLf-treated COVID-19 patients showed fast clinical symptoms recovery compared to the SOC-treated COVID-19 patients. In bLf-treated patients, a significant decrease in serum ferritin, IL-6, and D-dimers levels was observed. No adverse events were reported. These observations led us to speculate a potential role of bLf in the management of mild-to-moderate and asymptomatic COVID-19 patients
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