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VIsual System Activation by Ionizing Radiation: Modelling the irradiation setup for whole rabbit eye exposures
No full textThe earliest evidence of space radiation effects on brain functions has been the perception of phosphenes (flashes of light), reported by astronauts since the Apollo missions. The recently reported effects of radiation on sensory channels other than visual suggest, besides the largely investigated activation of retinal processes,
a direct action of radiation on neurons or neural networks. In particular, ionizing radiation may influence the biological signaling mainly due to calcium ion homeostasis. In this context, within the VISAIR project we are conducting an experimental study with ex vivo whole rabbit eyes, maintained bio-active in a suitable medium,
to investigate the activation of the visual system and analyze possible modulation of the effects with different LET/Z. Modelling is needed to interpret the results and extrapolate findings to radiation rates relevant for space exploration. We here present representative results obtained with the code PHITS, after implementation of a software replica of the experimental setup, to verify dosimetric quantities and characterize the radiation field in the target eye
Radiation dose estimates in DBT compared with FFDM: A brief analysis
No full textBreast cancer is reported as the second most common cancer in the world. The estimate for 2018 is 59 700 new cases of breast cancer (Bray F. et al., Cancer. J. Clin., 68 (2018) 394). The distribution of the incidence of breast cancer
is high especially in industrialized countries, followed by developing countries. The development of effective screening programs allows to lead the survival to 84% in
developed countries. Early diagnosis, in the context of these programs, is carried out using X-rays and the equipment used for this purpose is constantly updated to improve the detection capability for the same dose delivered. Nowadays, next to full-field digital mammography (FFDM), 3D technology is available on modern
mammography devices, such as Digital Breast Tomosynthesis (DBT). Some studies show that the use of DBT, combined with FFDM, or as a stand-alone technology, allows for a better diagnostic performance than FFDM alone (Skaane P. et al., Radiology, 267 (2013) 47; Ciatto S. et al., Lancet Oncol., 14 (2013) 583). In addition to the diagnostic capacity, of course, the dose to the population participating in the screening programs must also be investigated. Considering that the different manufacturers of digital mammography systems use different technologies to reconstruct pseudo-3D images, it is essential to check the radiation dose of various equipment available in healthcare facilities. The purpose of this work is to verify the radiation dose for a specific mammography unit used in both FFDM and DBT procedures
"Valutazione dello stato di salute ambientale del lago Patria ed ecosistemi limitrofi"_ Dati preliminari e indicazioni sui primi interventi attuabili
Get PDFPleuroparenchymal Fibroelastosis Associated with Crohn’s Disease: A New Aetiology?
Get PDFPleuroparenchymal fibroelastosis (PPFE) is a relatively rare interstitial lung disease (ILD) consisting of elastofibrosis involving the subpleural parenchyma and visceral pleura with an upper lobe predominance. It can be idiopathic or associated with some forms of autoimmune disease. The authors describe the case of a 78-year-old woman with a previous diagnosis of Crohn’s disease (CD). She presented with a protracted respiratory infection (with no significant history of previous infections), and underwent high-resolution chest computerized tomography that eventually showed alterations compatible with PPFE. After exclusion of other possible underlying causes, a possible link to CD was considered. Follow-up investigation at 12 months showed clinical and radiological stability and also stable lung function under treatment with hydroxychloroquine and prednisolone. This is the first report of PPFE in the context of CD. Future studies will be important to further investigate this pathological association and its prognostic implications
First-Degree Atrioventricular Block with Tachycardia from Paliperidone and Mirtazapine Overdose
Get PDFBackground: Paliperidone and mirtazapine are psychotropic agents associated with proarrhythmic effects. Case Presentation: A 21-year-old woman was admitted to the intensive care unit on two separate occasions for attempting suicide by overdosing on paliperidone and mirtazapine. During both admissions, the patient had atypical chest pain and a first-degree atrioventricular block (AVB) with paradoxical sinus tachycardia, which resolved with the discontinuation of paliperidone and mirtazapine and aggressive intravenous fluids. Conclusion: Drug-induced first-degree AVB from paliperidone and mirtazapine should be on the differential diagnosis in patients on paliperidone and/or mirtazapine who present with chest pain, tachycardia or new-onset first-degree AVB
Persistent Facial Oedema and Erythema in a Woman, An Uncommon Manifestation of Chronic Cutaneous Lupus Erythematosus
Get PDFManifestations of chronic cutaneous lupus erythematosus are variable. Periorbital and facial swelling occurs in dermatomyositis and systemic lupus, but it has been rarely reported as a manifestation of exclusively cutaneous lupus. A 48-year-old woman presented with a 16-year history of asymptomatic, bilateral swelling and erythema of her face with marked worsening after sun exposure. No systemic symptoms were associated. A complete evaluation did not reveal other findings. Cutaneous biopsy showed features of lupus erythematosus. She was treated with photoprotection, topical tacrolimus, hydroxychloroquine and azathioprine with a partial response. Facial swelling with erythema represents quite an unusual manifestation of chronic cutaneous lupus erythematosus. Dermatomyositis, systemic lupus and Morbihan disease are the main differential diagnoses
Cervical Lymphadenopathy in Two Young Women The Same Rare Diagnosis with Different Presentations
Get PDFKikuchi-Fujimoto disease (KFD) is a rare, benign and usually self-limiting disorder that more often affects young women, which is characterized by cervical lymphadenopathy and fever. Clinical presentation may be indistinguishable from other diseases, and its inclusion in the differential diagnosis of lymphoproliferative, infective and autoimmune diseases is essential. An association with systemic lupus erythematosus is acknowledged. We present 2 different cases of 2 young women with KFD; the first case highlights the classic diagnostic features of this rare entity, and the second, the findings when KFD occurs in association with systemic lupus erythematosus
Transient ST Segment Elevation in Two Patients with COVID-19 and a Normal Transthoracic Echocardiogram
Get PDFWe continue to learn about cardiac involvement in patients with COVID-19. These patients can develop acute coronary syndrome and severe myocarditis with a reduced ejection fraction. We describe two critically ill COVID-19 patients who developed ST elevation that resolved on repeat ECG without any intervention
Precise timing with the PICOSEC-Micromegas detector
No full textThis work presents the concept of the PICOSEC-Micromegas detector to achieve a time resolution below 30 ps. PICOSEC consists of a two-stage Micromegas detector coupled to a Cherenkov radiator and equipped with a photocathode. The results from single-channel prototypes as well as the understanding of the detector in terms of detailed simulations and preliminary results from a multichannel prototype are presented
TOPS project: Development of new fast timing plastic scintillators
No full textIn particle physics charged particles are measured exploiting many different detection strategies. The plastic scintillators are cheap, versatile and show good time response, thus are traditionally employed as timing detectors. TOPS (Time Of flight Plastic Scintillators) is an R&D project devoted to the synthesis and characterization of a novel class of plastic scintillators. Liquid and solid samples of tens of new scintillators have been tested and characterized. Some of them (2N, 1N, 2B, P2, T2) have shown a larger light output with respect to antracene, a standard benchmark material, and good timing properties. In order to improve the matching between the scintillators emission and the optimal trasmittive region in the absorption spectra, a doping material has been added as wave-shifter. The use of POPOP as doping improved the performances of a fraction of the scintillator samples. Based on the comparison of the light output values in measurements with cosmic rays, a selection of the most promising scintillators has been investigated also from the timing point of view. The scintillation time characteristics of the TOPS plastic samples have been studied with minimum ionizing particles using a commercial plastic scintillator BC-412 as a reference. The light output and timing properties have been also investigated with proton beams at different energies (70, 120, 170, 220 MeV) and show promising results providing a time of flight measurements accuracy of 150–300 ps. In this contribution, preliminary results obtained with this new class of scintillators developed in the TOPS project will be presented