Dosimetria interna: stima del parametro alfa del modello lineare-quadratico nel trattamento di radioembolizzazione epatica con microsfere marcate con 90Y.

Alcuni tipi di tumori epatici possono essere trattati con una particolare tecnica di radioterapia: la radioembolizzazione. Questa tecnica consiste nel somministrare al paziente un certo quantitativo di radioattività, tramite l'iniezione per via arteriosa di microsfere costituite da materiale biologicamente inerte, caricate con Ittrio-90, 90Y. L' 90Y decade prevalentemente β-, quindi, dato il corto range degli e-, è ottimale per rilasciare una dose elevata in una regione piuttosto circoscritta. Questo tipo di trattamento costituisce l'argomento di questo lavoro di tesi, il cui obiettivo è cercare di incrementarne l'efficacia terapeutica, attraverso l'ottimizzazione della procedura di calcolo della dose assorbita dalla lesione tumorale e dagli organi sani. I dati per il calcolo della dose verranno presi da immagini CT-SPECT, ottenute iniettando al paziente dei magroaggregati di albumina tecneziati (99mTc-MMA) nello stesso sito in cui verranno inettate le microsfere: questo perché si ipotizza che i 99mTc-MMA simulino bene il comportamento delle microsfere. Si sfrutterà invece la debolissima emissione β+ dell'90Y per fare una dosimetria di controllo post-trattamento. Per effettuare tali calcoli di dose 3D ci avvarremo del metodo semplificato, già oggetto di un precedente lavoro di tesi e pubblicato su Med. Phys. 40(4), April 2013, mentre le valutazioni verranno fatte tenendo conto degli istogrammi dose-volume (DVH, Dose-Volume Histogram) e dell'UTCP (Uncomplicated Tumour Control Probability) che ci permetterà di predire quale sarebbe l'attività che costituisce il miglior compromesso tra un'alta dose assorbita dalla lesione ed una bassa radiotossicità ai tessuti sani. Il modello radiobiologico di riferimento è il modello lineare-quadratico, in approssimazione lineare: questo modello, semplice matematicamente ma molto potente dal punto di vista predittivo, permette di calcolare la frazione di sopravvivenza, ovvero il numero di cellule che sopravvivono ad una determinata dose, dato da N=N0 exp (-α D), dove N è il numero di cellule sopravvissute alla dose D, partendo da un numero complessivo di cellule pari a N0, mentre α è il parametro che ci proponiamo di calcolare. Da esso dipendono il TCP (Tumor Control Probability) e l'NTCP (Normal Tissue Complication Probability), mentre l'UTCP non è altro che il prodotto del TCP per la probabilità di non avere complicazioni al tessuto sano, in formula UTCP=TCP(1-NTCP). Il valore di attività da somministrare corrisponderà al massimo di questa curva, che indica, per l'appunto, il valore di miglior compromesso tra un'alta dose assorbita dalla lesione ed una bassa dose al tessuto sano. Va precisato che non sempre questo calcolo porta a dei risultati attuabili dal punto di vista medico: in tali casi ci avvarremo di altri metodi per decidere l'attività da somministrare, basati su valutazioni fatte esclusivamente sui DVH. In ogni caso, è di fondamentale importanza nell'applicazione degli algoritmi di calcolo della dose 3D che i conteggi misurati sulle immagini SPECT e PET siano proporzionali all'attività somministrata: per questo motivo verrà eseguita una taratura di entrambi i tomografi (SPECT e PET) con lo stesso fantoccio standard (caricato dei radioemettitori opportuni) e con i tomografi settati come se si trattasse di pazienti

A New Approach for Human Factor Integration into Ship Design Process

Ship safety and operations are driving issues of ship design and it is well recognized that such performances are strongly related to Human Factor (HF). In the paper a methodology to integrate HF into the ship design process since an early stage is envisaged, with the aim to improve the overall ship resilience when dealing with uncertainty of performance implied by HF element. The System-Theoretic Accident Model Process (STAMP, Leveson 2003) is investigated as a suitable methodology able to provide a significant asset in such perspective. The approach is widely applied in many industrial and transportation fields but in order to better understand its application into the marine context, a specific application will be briefly commented. In the attempt to define a comprehensive procedure, as a preliminary overview, some selected models suitable to classify the human behavior will be considered with specific focus on the reasons for performance degrade and/or uncertainty

Transarterial radioembolization for hepatocellular carcinoma: An update and perspectives

In the last decade trans-arterial radioembolization has given promising results in the treatment of patients with intermediate or advanced stage hepatocellular carcinoma (HCC), both in terms of disease control and tolerability profile. This technique consists of the selective intra-arterial administration of microspheres loaded with a radioactive compound (usually Yttrium90), and exerts its therapeutic effect through the radiation carried by these microspheres. A careful and meticulous selection of patients is crucial before performing the radioembolization to correctly perform the procedure and reduce the incidence of complications. Radioembolization is a technically complex and expensive technique, which has only recently entered clinical practice and is supported by scant results from phase III clinical trials. Nevertheless, it may represent a valid alternative to transarterial chemoembolization (TACE) in the treatment of intermediate-stage HCC patients, as shown by a comparative retrospective assessment that reported a longer time to progression, but not of overall survival, and a more favorable safety profile for radioembolization. In addition, this treatment has reported a higher percentage of tumor shrinkage, if compared to TACE, for pre-transplant downsizing and it represents a promising therapeutic option in patients with large extent of disease and insufficient residual liver volume who are not immediately eligible for surgery. Radioembolization might also be a suitable companion to sorafenib in advanced HCC or it can be used as a potential alternative to this treatment in patients who are not responding or do not tolerate sorafenib

Vaccination against SARS-CoV-2 in pregnancy during the Omicron wave: the prospective cohort study of the Italian obstetric surveillance system

Objectives: Evidence on the effects of the SARS-CoV-2 Omicron variant on vaccinated and unvaccinated pregnant women is sparse. This study aimed to compare maternal and perinatal outcomes of women infected with SARS-CoV-2 during the Omicron wave in Italy, according to their vaccine protection.Methods: This national prospective cohort study enrolled pregnant women with a positive SARS-CoV-2 nasopharyngeal swab within 7 days of hospital admission between 1 January and 31 May, 2022. Women who received at least one dose of vaccine during pregnancy and those who completed the vaccine cycle with the first booster were considered protected against moderate or severe COVID-19 (MSCD). A multivariable logistic regression model evaluated the association between vaccine protection and disease severity. Maternal age, educational level, citizenship, area of birth, previous comorbidities, and obesity were analysed as potential risk factors. Results: MSCD was rare (41/2147, 1.9%; 95% CI, 1.4-2.6), and the odds of developing it were significantly higher among unprotected women (OR, 2.78; 95% CI, 1.39-5.57). Compared with protected women (n = 1069), the unprotected (n = 1078) were more often younger, with lower educational degrees, and foreigners. A higher probability of MSCD was found among women with previous comorbidities (OR, 2.86; 95% CI, 1.34-6.12) and those born in Asian countries (OR, 3.05; 95% CI, 1.23-7.56). The percentage of preterm birth was higher among women with MSCD compared with milder cases (32.0% [8/25] versus 8.4% [161/1917], p < 0.001) as well as the percentage of caesarean section (52.0% [13/25] versus 31.6% [606/1919], p 0.029). Discussion: Although severe maternal and perinatal outcomes were rare, their prevalence was significantly higher among women without vaccine protection. Vaccination during pregnancy has the potential to protect both the mother and the baby, and it is therefore strongly recommended. Edoardo Corsi Decenti, Clin Microbiol Infect 2023;29:772 (c) 2023 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved

A singular case of frontal meningoencephalocele associated a with Lhermitte-Duclos syndrome

Meningoencephalocele (MEC) refers to a herniation of intracranial contents, through a defect of the skull base into the nasal or paranasal cavities. It is a rare entity, typically congenital, originating from a defect during or immediately after the neurulation process. Less frequently it can be secondary, especially in adults as in the present case, resulting from traumatic injuries, surgery, hydrocephalus, and chronic sinusitis. Diagnosis is based on clinical evaluation, CT (computed tomography) scans and MRI (magnetic resonance imaging). B2-transferrin dosage may be useful in unclear cases. The clinical case herein presented refers to an unusual presentation of a MEC in the frontal sinus associated with Lhermitte-Duclos Syndrome, a condition which led over time to hydrocephalus and intracranial hypertension, well-known predisposing factors for MEC genesis. A combined transnasal endoscopic and external approach was performed to completely dominate the herniation and adequately reconstruct the bony defect with a gasket seal technique. To date, the patient has no recurrence of MEC

Simulation as a training method for electricity workers' safety

Background: Simulation is a useful method to improve learning and increase the safety of work operations, both for technical and non-technical skills. However, the observation, assessment, and feedback about these skills is particularly complex, because the process needs expert observers, and the feedback could be judgmental and ineffective. Therefore, a structured process to develop effective simulation scenarios and tools for the observation and feedback about performance is crucial. To this aim, in the present research, we developed a training model for electricity distribution workers, based on high fidelity simulation. Methods: We designed simulation scenarios based on real cases, developed, and tested a set of observation and rating forms for the non-technical skills behavioral markers, and we tracked behaviors based on non-verbal cues (physiological and head orientation parameters). Results: The training methodology proved to be highly appreciated by the participants and effective in fostering reflexivity. An in-depth analysis of physiological indexes and behaviors compliant to safety procedures revealed that breath rate and heart rate patterns commonly related with mindful and relaxed states were correlated with compliant behaviors, and patterns typical of stress and anxiety were correlated with non-compliant behaviors. Conclusions: a new training method based on high fidelity simulation, addressing both technical and non-technical skills is now available for fostering self-reflection and safety for electricity distribution workers. Future research should assess the long-term effectiveness of high-fidelity simulation for electricity workers, and should investigate non-invasive and real-time methods for tracking physiological parameters

Two faces of internality: Measuring overconfident and cautious driving locus of control

Locus of Control (LoC) is the extent to which individuals believe they can control events in their lives. Individuals with high \u2018internal\u2019 LoC think that they can control the situation; individuals with high \u2018external\u2019 LoC feel the opposite. LoC has been used to predict drivers\u2019 behavior, but results are inconsistent: in some studies internal LoC is associated to safe driving behavior; in others to high rate of accidents; in others no relationship is found. We hypothesized that these findings reflect two different dimensions of internal LoC: (i) internal LoC makes people feel more responsible of their actions, so they are more cautious, and (ii) internal LoC makes people feel totally in control, so they push the boundaries. In this study we developed a new measure, the Driving Locus of Control Scale (DLOC), that differentiates two dimensions of internal LoC: overconfident and cautious. The DLOC was validated through exploratory (Sample 1: N = 187, 56% female, age 37 \ub115) and confirmatory (Sample 2: N=325, 27% female, age 19 \ub1 7) factor analysis. The final measurement model comprised 11 items that loaded on three correlated factors (Overconfident Internal LoC, Cautious Internal LoC, External LoC) and showed good fit in both samples. To investigate construct validity, the Driving Internality (DI) - Driving Externality (DE) scale was administered in Sample 1. The Overconfident factor correlated with the DI (r=.40), and the External with the DE (r=.44). The internal/cautious factor correlated with neither the DI nor the DE. The results support the need to distinguish two dimensions of internal LoC, that might disambiguate the contrasting results on the relationship between risky driving and internal LoC

Privacy Knowledge Base for Supporting Decision-Making in Software Development

Integrating security and privacy requirements at every stage of the software development cycle is critical to guarantee the confidentiality, integrity and availability of the system and consequently of the data. Developers need to be supported in this challenge, as many different skills are required to respond effectively to the growing number of cyber-attacks. In such a context, this research study endeavors to define the key elements that support decision-making in privacy oriented software development. A Privacy Knowledge Base (PKB) is defined to support developers’ decisions in all software development phases, and a prototype (PKB-Tool) is developed to operationally integrate privacy and security requirements into the development of new systems and the re-engineering of legacy systems. An ongoing experimentation in the context of an industrial project is presented to validate the efficacy of the 5 key elements in supporting developers in integrating privacy and security requirements in the software life cycle