Simulation of the response of a diamond-based radiation detector to ultra-short and intense high-energy electron pulses

Single-crystal synthetic diamond sensors have been widely used in radiation dosimetry and beam diagnostics. The foreseen harsh radiation environment in electron-positron colliders at the luminosity frontier requires a thorough investigation of diamond's response to large radiation burst, in particular, to intense high-energy electron pulses. In this article, a two-step numerical simulation approach (Sentaurus~+~LTspice) is proposed to explore this topic. Time response of the diamond detector is simulated via TCAD-Sentaurus while the transmission effect of the electronic circuit is taken into account using LTspice. Good agreement is observed between results of the numerical simulation and preliminary experimental data from detector's exposure to high-energy sub-picosecond electron pulses, on both the amplitude and the shape of the induced signals. This simulation combination is a novel approach to designing and optimising diamond detectors for radiation and beam loss monitoring in particle physics experiments

Note tassonomiche e biosistematiche su Anthemis aeolica (Asteraceae).

Sono riportati i risultati relativi alla caratterizzazione morfologica, distribuzione attuale , ecologia e correlazioni sistematiche della specie endemica Anthemis aeolic

AB0563 DISCONTINUATION OF ANTI-TNFα IN PATIENTS WITH PSORIATIC ARTHRITIS: A SINGLE-CENTER EXPERIENCE

Background:TNF inhibitors have been largely demonstrated to be effective and reasonably safe for the treatment of psoriatic arthritis (PsA). Current EULAR guidelines recommend the use of an anti-TNF as first choice treatment in patients with PsA for whom a synthetic DMARD (usually methotrexate or leflunomide) is not efficacious or not well tolerated [1]. In a scenario where biologic treatments are easily available, and the treat to target strategy is widely accepted, a complete disease remission or at least a minimal disease activity are considered realistic goals to be achieved in a growing proportion of patients [2]. However, there remains very little research regarding anti-TNF discontinuation in patients who achieved a complete remission [3-5].Objectives:The primary aim of this study was to measure the disease-free interval after anti-TNF discontinuation, secondary it was investigated whether the use of Power Doppler Ultrasound (PDUS) and Contrast Enhanced Ultrasound (CEUS) could improve the diagnostic accuracy in the recognition of the relapse. Finally, we wanted to characterize the clinical features of the disease recurrence.Methods:From June 2018, 35 patients with PsA (27 males and 8 female) treated with anti-TNF, in stable remission were prospectively monitored for 1 year after treatment discontinuation. Remission was defined as documented absence of clinical and ultrasonographic signs of arthritis or enthesitis. Complete rheumatological and dermatological examinations were performed in all participants, at baseline and every 8-12 weeks: American College of Rheumatology (ACR) 66-68 joint count; Psoriasis Area Severity Index (PASI); patient pain visual analog score (VAS); patient global disease activity VAS; Health Assessment Questionnaire (HAQ); Leeds Enthesitis Index (LEI); Bath Ankylosing Spondylitis Disease Activity Index (BASDAI); Bath Ankylosing Spondylitis Functional Index (BASFI); Power Doppler Ultrasound (PDUS) of the involved joints and entheses, Contrast Enhanced Ultrasound (CEUS) of a selected joint or enthesis and laboratory inflammation tests.Results:31 out of the 35 enrolled patients, experienced a disease recurrence with an average disease-free interval of 27.9±21.1 weeks (Figure 1). In 3 patients the treatment was restored for a relapse of the skin psoriasis, 8 patients reported only axial symptoms of disease relapse and 20 patients had both axial and peripheral joints involvement (average DAPSA score of 23.6±11.1; average BASDAI score of 4.7±2.6; average BASFI score 4.5±2.9). In all cases the disease flare was moderate and all patients promptly regained remission after restarting the treatment. Both PDUS and CEUS were safe and reliable showing a good percentage of accordance (95,4%) in detecting synovitis and enthesitis.Conclusion:The rate of disease relapse of PsA after anti-TNF discontinuation is relevant. However the disease-free interval was not short. Retreatment with the same anti-TNF was effective and safe.References:[1]Gossec L, Baraliakos X, Kerschbaumer A, et al. EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2019 update. Ann Rheum Dis. 2020 Jun;79(6):700-712.[2]Dures E, Shepperd S, Mukherjee S, et al. Treat-to-target in PsA: methods and necessity. RMD Open. 2020 Feb;6(1):e001083.[3]Stober C, Ye W, Guruparan T, et al. Prevalence and predictors of tumour necrosis factor inhibitor persistence in psoriatic arthritis. Rheumatology (Oxford). 2018 Jan 1;57(1):158-163.[4]Huynh DH, Boyd TA, Etzel CJ, et al. Persistence of low disease activity after tumour necrosis factor inhibitor (TNFi) discontinuation in patients with psoriatic arthritis. RMD Open. 2017 Jan 16;3(1):e000395.[5]Ye W, Tucker LJ, Coates LC. Tapering and Discontinuation of Biologics in Patients with Psoriatic Arthritis with Low Disease Activity. Drugs. 2018 Nov;78(16):1705-1715.Disclosure of Interests:None declared

Efficacy of oral hyposensitization in allergic contact dermatitis caused by nickel

Background. Nickel contact allergy remains common in Western countries, and the dermatitis may require prolonged treatment. The development of new strategies aimed at improving the quality of life of affected individuals is needed. Objectives. To investigate the efficacy of oral hyposensitization in nickel-allergic individuals and how this affects in vitro T cell responsiveness to the metal. Methods. Twenty-eight nickel-allergic patients received a daily dose of 50 μg of elemental nickel (given as NiSO 4·6H 2O) in cellulose capsules for 3 months. Severity of clinical manifestations, in vivo nickel responsiveness and in vitro T cell responses to the metal were assessed after 1 and 3 months. Results. Twenty-six patients finished the study. In these patients, oral hyposensitization ameliorated clinical manifestations despite continued nickel exposures, and increased the threshold of skin responsiveness to nickel. The 12 enrolled patients in the immunological study showed decreased in vitro T lymphocyte responsiveness to the metal, in terms of both cell proliferation and cytokine release. In the 1-year follow-up, 50% of the patients experienced relapses of the clinical manifestations at sites of topical exposure to nickel. Conclusions. Our study suggested therapeutic efficacy of oral hyposensitization in allergic individuals. Placebo-controlled studies are required to confirm the results and determine the optimal therapeutic regimen for prolonged beneficial effects

Facial Abrikosoff tumour. The role of the dermatologist during COVID-19 pandemic

No abstract availabl

Skin manifestations after ionizing radiation exposure. a systematic review

Morphological and functional skin alterations secondary to the action of ionizing radiation are well documented. In addition to its application in the medical field, ionizing radiation represents a public health problem for diagnostic and therapeutic purposes due to the potential risk of exposure to unexpected events, such as nuclear accidents or malicious acts. With regard to the use of ionizing radiations in the medical field, today, they constitute a fundamental therapeutic method for various neoplastic pathologies. Therefore, the onset of adverse skin events induced by radiation represents a widespread and not negligible problem, affecting 95% of patients undergoing radiotherapy. A systematic literature search was performed from July 2021 up to August 2021 using PubMed, Embase, and Cochrane databases. Articles were screened by title, abstract and full text as needed. A manual search among the references of the included papers was also performed. This systematic review describes the various skin reactions that can arise following exposure to ionizing radiation and which significantly impact the quality of life, especially in cancer patients

Vanadium pentoxide induces the secretion of CXCL9 and CXCL10 chemokines in thyroid cells

Vanadium is a grey metal, existing in different states of oxidation, whose most common form in commercial products is vanadium pentoxide (V2O5). All vanadium compounds have been considered toxic. A carcinogenic role of vanadium on the thyroid has recently been proposed. However no in vivo or in vitro studies have evaluated thyroid disruption in humans and/or animals after exposure to vanadium. In the present study we evaluate the effect of V2O5on proliferation, and chemokine secretion in normal thyrocytes. Our study demonstrated that V2O5has no effect on thyroid follicular cell viability or proliferation, but it is able to induce the secretion of T-helper (Th)1 chemokines into the thyroid, synergistically increasing the effect of important Th1 cytokines such as interferon (IFN)γ and tumor necrosis factor (TNF)α. Through this process, V2O5promotes the induction and perpetuation of an inflammatory reaction in the thyroid. Further studies are necessary to evaluate thyroid function, and nodules, in subjects occupationally exposed, or living in polluted areas