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  1. Article ; Online: CD80 expression is upregulated by TP53 activation in human cancer epithelial cells.

    Scarpa, Melania / Marchiori, Chiara / Scarpa, Marco / Castagliuolo, Ignazio

    Oncoimmunology

    2021  Volume 10, Issue 1, Page(s) 1907912

    Abstract: CD80 is recognized as one of the most potent costimulatory molecules by which immune cells limit cancer progression; however, the current understanding of the regulation of its expression on human tumor cells is limited. The TP53 tumor suppressor plays a ...

    Abstract CD80 is recognized as one of the most potent costimulatory molecules by which immune cells limit cancer progression; however, the current understanding of the regulation of its expression on human tumor cells is limited. The TP53 tumor suppressor plays a critical role in cancer and its significant role in the control of immune responses is emerging. Here, we evaluated the role of TP53 as a regulator of CD80 expression in human cancer cells. A set of well-known TP53-reactivating compounds were used on TP53-wild-type, TP53-deficient, TP53-mutated and TP53-knockdown cancer cell lines to determine if TP53 can regulate CD80. CD80 expression was analyzed in samples from patients with TP53-active vs TP53-inactive Colon Adenocarcinomas (COAD) from TCGA panCancer Atlas. We report that the pharmacological activation of TP53 can stimulate the expression of CD80 in human tumor cells of epithelial origin. We also provide evidence that CD80 expression exhibits a strong correlation with TP53 activation in a subgroup of colon tumors with better overall survival. These results confirm the link between TP53 and immune surveillance in human cancer and provide the possibility that conventional TP53-activation approaches for tumoricidal effects may be repurposed for immunotherapy strategies.
    MeSH term(s) B7-1 Antigen/genetics ; Cell Adhesion Molecules ; Colonic Neoplasms/genetics ; Epithelial Cells ; Humans ; Immunotherapy ; Tumor Suppressor Protein p53/genetics
    Chemical Substances B7-1 Antigen ; Cell Adhesion Molecules ; TP53 protein, human ; Tumor Suppressor Protein p53
    Language English
    Publishing date 2021-04-05
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2645309-5
    ISSN 2162-402X ; 2162-4011
    ISSN (online) 2162-402X
    ISSN 2162-4011
    DOI 10.1080/2162402X.2021.1907912
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: Fooling Explanations in Text Classifiers

    Ivankay, Adam / Girardi, Ivan / Marchiori, Chiara / Frossard, Pascal

    2022  

    Abstract: State-of-the-art text classification models are becoming increasingly reliant on deep neural networks (DNNs). Due to their black-box nature, faithful and robust explanation methods need to accompany classifiers for deployment in real-life scenarios. ... ...

    Abstract State-of-the-art text classification models are becoming increasingly reliant on deep neural networks (DNNs). Due to their black-box nature, faithful and robust explanation methods need to accompany classifiers for deployment in real-life scenarios. However, it has been shown in vision applications that explanation methods are susceptible to local, imperceptible perturbations that can significantly alter the explanations without changing the predicted classes. We show here that the existence of such perturbations extends to text classifiers as well. Specifically, we introduceTextExplanationFooler (TEF), a novel explanation attack algorithm that alters text input samples imperceptibly so that the outcome of widely-used explanation methods changes considerably while leaving classifier predictions unchanged. We evaluate the performance of the attribution robustness estimation performance in TEF on five sequence classification datasets, utilizing three DNN architectures and three transformer architectures for each dataset. TEF can significantly decrease the correlation between unchanged and perturbed input attributions, which shows that all models and explanation methods are susceptible to TEF perturbations. Moreover, we evaluate how the perturbations transfer to other model architectures and attribution methods, and show that TEF perturbations are also effective in scenarios where the target model and explanation method are unknown. Finally, we introduce a semi-universal attack that is able to compute fast, computationally light perturbations with no knowledge of the attacked classifier nor explanation method. Overall, our work shows that explanations in text classifiers are very fragile and users need to carefully address their robustness before relying on them in critical applications.
    Keywords Computer Science - Machine Learning ; Computer Science - Computation and Language ; Computer Science - Cryptography and Security
    Subject code 006
    Publishing date 2022-06-07
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Disparities in access to COVID-19 vaccine in Verona, Italy: a cohort study using local health immunization data.

    Benoni, Roberto / Sartorello, Anna / Moretti, Francesca / Marchiori, Francesco / Accordini, Luciana / Postiglione, Chiara / Coffele, Viviana / Tardivo, Stefano

    Frontiers in public health

    2023  Volume 11, Page(s) 1167414

    Abstract: Introduction: Migrant populations worldwide were disproportionately impacted by the COVID-19 pandemic. Although substantial resources have been invested in scaling COVID-19 vaccination campaigns, globally vaccine rate and uptake remained low among ... ...

    Abstract Introduction: Migrant populations worldwide were disproportionately impacted by the COVID-19 pandemic. Although substantial resources have been invested in scaling COVID-19 vaccination campaigns, globally vaccine rate and uptake remained low among migrants from across many countries. This study aimed to explore the country of birth as a factor influencing access to the COVID-19 vaccine.
    Methods: This retrospective cohort study included adults vaccinated against SARS-CoV-2 receiving at least one dose in the Verona province between 27 December 2020 and 31 December 2021. Time-to-vaccination was estimated as the difference between the actual date of each person's first dose of COVID-19 vaccination and the date in which the local health authorities opened vaccination reservations for the corresponding age group. The birth country was classified based on both the World Health Organization regions and the World Bank country-level economic classification. Results were reported as the average marginal effect (AME) with corresponding 0.95 confidence intervals (CI).
    Results: During the study period, 7,54,004 first doses were administered and 5,06,734 (F = 2,46,399, 48.6%) were included after applying the exclusion criteria, with a mean age of 51.2 years (SD 19.4). Migrants were 85,989 (17.0%, F = 40,277, 46.8%), with a mean age of 42.4 years (SD 13.3). The mean time-to-vaccination for the whole sample was 46.9 days (SD 45.9), 41.8 days (SD 43.5) in the Italian population, and 71.6 days (SD 49.1) in the migrant one (p < 0.001). The AME of the time-to-vaccination compared to the Italian population was higher by 27.6 [0.95 CI 25.4-29.8], 24.5 [0.95 CI 24.0-24.9], 30.5 [0.95 CI 30.1-31.0] and 7.3 [0.95 CI 6.2-8.3] days for migrants from low-, low-middle-, upper-middle- and high-income countries, respectively. Considering the WHO region, the AME of the time-to-vaccination compared to the Italian group was higher by 31.5 [0.95 CI 30.6-32.5], 31.1 [0.95 CI 30.6-31.5], and 29.2 [0.95 CI 28.5-29.9] days for migrants from African, European, and East-Mediterranean regions, respectively. Overall, time-to-vaccination decreased with increasing age (p < 0.001). Although both migrants and Italians mainly used hub centers (>90%), migrants also used pharmacies and local health units as alternative sites (2.9% and 1.5%, respectively), while Italians (3.3%) and migrants from the European region (4.2%) relied more on family doctors.
    Conclusion: The birth country of migrants influenced access to COVID-19 vaccine both in terms of time-to-vaccination and vaccination points used, especially for the LIC migrant group. Public health authorities should take socio-cultural and economic factors into consideration for tailored communication to people from migrant communities and for planning a mass vaccination campaign.
    MeSH term(s) Adult ; Humans ; Middle Aged ; COVID-19 Vaccines ; Cohort Studies ; Retrospective Studies ; Pandemics/prevention & control ; COVID-19/epidemiology ; COVID-19/prevention & control ; SARS-CoV-2 ; Vaccination ; Italy/epidemiology
    Chemical Substances COVID-19 Vaccines
    Language English
    Publishing date 2023-06-15
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2711781-9
    ISSN 2296-2565 ; 2296-2565
    ISSN (online) 2296-2565
    ISSN 2296-2565
    DOI 10.3389/fpubh.2023.1167414
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Online: Estimating the Adversarial Robustness of Attributions in Text with Transformers

    Ivankay, Adam / Rigotti, Mattia / Girardi, Ivan / Marchiori, Chiara / Frossard, Pascal

    2022  

    Abstract: Explanations are crucial parts of deep neural network (DNN) classifiers. In high stakes applications, faithful and robust explanations are important to understand and gain trust in DNN classifiers. However, recent work has shown that state-of-the-art ... ...

    Abstract Explanations are crucial parts of deep neural network (DNN) classifiers. In high stakes applications, faithful and robust explanations are important to understand and gain trust in DNN classifiers. However, recent work has shown that state-of-the-art attribution methods in text classifiers are susceptible to imperceptible adversarial perturbations that alter explanations significantly while maintaining the correct prediction outcome. If undetected, this can critically mislead the users of DNNs. Thus, it is crucial to understand the influence of such adversarial perturbations on the networks' explanations and their perceptibility. In this work, we establish a novel definition of attribution robustness (AR) in text classification, based on Lipschitz continuity. Crucially, it reflects both attribution change induced by adversarial input alterations and perceptibility of such alterations. Moreover, we introduce a wide set of text similarity measures to effectively capture locality between two text samples and imperceptibility of adversarial perturbations in text. We then propose our novel TransformerExplanationAttack (TEA), a strong adversary that provides a tight estimation for attribution robustness in text classification. TEA uses state-of-the-art language models to extract word substitutions that result in fluent, contextual adversarial samples. Finally, with experiments on several text classification architectures, we show that TEA consistently outperforms current state-of-the-art AR estimators, yielding perturbations that alter explanations to a greater extent while being more fluent and less perceptible.
    Keywords Computer Science - Machine Learning ; Computer Science - Artificial Intelligence
    Subject code 006
    Publishing date 2022-12-18
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Disparities in access to COVID-19 vaccine in Verona, Italy

    Roberto Benoni / Anna Sartorello / Francesca Moretti / Francesco Marchiori / Luciana Accordini / Chiara Postiglione / Viviana Coffele / Stefano Tardivo

    Frontiers in Public Health, Vol

    a cohort study using local health immunization data

    2023  Volume 11

    Abstract: IntroductionMigrant populations worldwide were disproportionately impacted by the COVID-19 pandemic. Although substantial resources have been invested in scaling COVID-19 vaccination campaigns, globally vaccine rate and uptake remained low among migrants ...

    Abstract IntroductionMigrant populations worldwide were disproportionately impacted by the COVID-19 pandemic. Although substantial resources have been invested in scaling COVID-19 vaccination campaigns, globally vaccine rate and uptake remained low among migrants from across many countries. This study aimed to explore the country of birth as a factor influencing access to the COVID-19 vaccine.MethodsThis retrospective cohort study included adults vaccinated against SARS-CoV-2 receiving at least one dose in the Verona province between 27 December 2020 and 31 December 2021. Time-to-vaccination was estimated as the difference between the actual date of each person's first dose of COVID-19 vaccination and the date in which the local health authorities opened vaccination reservations for the corresponding age group. The birth country was classified based on both the World Health Organization regions and the World Bank country-level economic classification. Results were reported as the average marginal effect (AME) with corresponding 0.95 confidence intervals (CI).ResultsDuring the study period, 7,54,004 first doses were administered and 5,06,734 (F = 2,46,399, 48.6%) were included after applying the exclusion criteria, with a mean age of 51.2 years (SD 19.4). Migrants were 85,989 (17.0%, F = 40,277, 46.8%), with a mean age of 42.4 years (SD 13.3). The mean time-to-vaccination for the whole sample was 46.9 days (SD 45.9), 41.8 days (SD 43.5) in the Italian population, and 71.6 days (SD 49.1) in the migrant one (p < 0.001). The AME of the time-to-vaccination compared to the Italian population was higher by 27.6 [0.95 CI 25.4–29.8], 24.5 [0.95 CI 24.0–24.9], 30.5 [0.95 CI 30.1–31.0] and 7.3 [0.95 CI 6.2–8.3] days for migrants from low-, low-middle-, upper-middle- and high-income countries, respectively. Considering the WHO region, the AME of the time-to-vaccination compared to the Italian group was higher by 31.5 [0.95 CI 30.6–32.5], 31.1 [0.95 CI 30.6–31.5], and 29.2 [0.95 CI 28.5–29.9] days for migrants from African, ...
    Keywords COVID-19 ; health inequities ; migrants ; SARS-CoV-2 ; healthcare access ; COVID-19 vaccine ; Public aspects of medicine ; RA1-1270
    Subject code 306
    Language English
    Publishing date 2023-06-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: Determination of the Spatial Anisotropy of the Surface MicroStructures of Different Implant Materials: An Atomic Force Microscopy Study.

    Gambardella, Alessandro / Marchiori, Gregorio / Maglio, Melania / Russo, Alessandro / Rossi, Chiara / Visani, Andrea / Fini, Milena

    Materials (Basel, Switzerland)

    2021  Volume 14, Issue 17

    Abstract: Many biomaterials' surfaces exhibit directional properties, i.e., possess spatial anisotropy on a range of spatial scales spanning from the domain of the naked eye to the sub-micrometer level. Spatial anisotropy of surface can influence the mechanical, ... ...

    Abstract Many biomaterials' surfaces exhibit directional properties, i.e., possess spatial anisotropy on a range of spatial scales spanning from the domain of the naked eye to the sub-micrometer level. Spatial anisotropy of surface can influence the mechanical, physicochemical, and morphological characteristics of the biomaterial, thus affecting its functional behavior in relation, for example, to the host tissue response in regenerative processes, or to the efficacy of spatially organized surface patterns in avoiding bacterial attachment. Despite the importance of the availability of quantitative data, a comprehensive characterization of anisotropic topographies is generally a hard task due to the proliferation of parameters and inherent formal complications. This fact has led so far to excessive simplification that has often prevented researchers from having comparable results. In an attempt to overcome these issues, in this work a systematic and multiscale approach to spatial anisotropy is adopted, based on the determination of only two statistical parameters of surface, namely the texture aspect ratio
    Language English
    Publishing date 2021-08-24
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2487261-1
    ISSN 1996-1944
    ISSN 1996-1944
    DOI 10.3390/ma14174803
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Book ; Online: FAR

    Ivankay, Adam / Girardi, Ivan / Marchiori, Chiara / Frossard, Pascal

    A General Framework for Attributional Robustness

    2020  

    Abstract: Attribution maps are popular tools for explaining neural networks predictions. By assigning an importance value to each input dimension that represents its impact towards the outcome, they give an intuitive explanation of the decision process. However, ... ...

    Abstract Attribution maps are popular tools for explaining neural networks predictions. By assigning an importance value to each input dimension that represents its impact towards the outcome, they give an intuitive explanation of the decision process. However, recent work has discovered vulnerability of these maps to imperceptible adversarial changes, which can prove critical in safety-relevant domains such as healthcare. Therefore, we define a novel generic framework for attributional robustness (FAR) as general problem formulation for training models with robust attributions. This framework consist of a generic regularization term and training objective that minimize the maximal dissimilarity of attribution maps in a local neighbourhood of the input. We show that FAR is a generalized, less constrained formulation of currently existing training methods. We then propose two new instantiations of this framework, AAT and AdvAAT, that directly optimize for both robust attributions and predictions. Experiments performed on widely used vision datasets show that our methods perform better or comparably to current ones in terms of attributional robustness while being more generally applicable. We finally show that our methods mitigate undesired dependencies between attributional robustness and some training and estimation parameters, which seem to critically affect other competitor methods.
    Keywords Computer Science - Machine Learning
    Subject code 006
    Publishing date 2020-10-14
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article: Learning Analytics Applied to Clinical Diagnostic Reasoning Using a Natural Language Processing-Based Virtual Patient Simulator: Case Study.

    Furlan, Raffaello / Gatti, Mauro / Mene, Roberto / Shiffer, Dana / Marchiori, Chiara / Giaj Levra, Alessandro / Saturnino, Vincenzo / Brunetta, Enrico / Dipaola, Franca

    JMIR medical education

    2022  Volume 8, Issue 1, Page(s) e24372

    Abstract: Background: Virtual patient simulators (VPSs) log all users' actions, thereby enabling the creation of a multidimensional representation of students' medical knowledge. This representation can be used to create metrics providing teachers with valuable ... ...

    Abstract Background: Virtual patient simulators (VPSs) log all users' actions, thereby enabling the creation of a multidimensional representation of students' medical knowledge. This representation can be used to create metrics providing teachers with valuable learning information.
    Objective: The aim of this study is to describe the metrics we developed to analyze the clinical diagnostic reasoning of medical students, provide examples of their application, and preliminarily validate these metrics on a class of undergraduate medical students. The metrics are computed from the data obtained through a novel VPS embedding natural language processing techniques.
    Methods: A total of 2 clinical case simulations (tests) were created to test our metrics. During each simulation, the students' step-by-step actions were logged into the program database for offline analysis. The students' performance was divided into seven dimensions: the identification of relevant information in the given clinical scenario, history taking, physical examination, medical test ordering, diagnostic hypothesis setting, binary analysis fulfillment, and final diagnosis setting. Sensitivity (percentage of relevant information found) and precision (percentage of correct actions performed) metrics were computed for each issue and combined into a harmonic mean (F
    Results: The mean overall scores were consistent between test 1 (mean 0.59, SD 0.05) and test 2 (mean 0.54, SD 0.12). For each student, the overall performance was achieved through a different contribution in collecting and analyzing information. Methodological scores highlighted discordances between the reference diagnostic pattern previously set by the teacher and the one pursued by the student. No significant correlation was found between the VPS scores and hematology examination scores.
    Conclusions: Different components of the students' diagnostic process may be disentangled and quantified by appropriate metrics applied to students' actions recorded while addressing a virtual case. Such an approach may help teachers provide students with individualized feedback aimed at filling competence drawbacks and methodological inconsistencies. There was no correlation between the hematology curricular examination score and any of the proposed scores as these scores address different aspects of students' medical knowledge.
    Language English
    Publishing date 2022-03-03
    Publishing country Canada
    Document type Journal Article
    ISSN 2369-3762
    ISSN 2369-3762
    DOI 10.2196/24372
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Probable airborne transmission in a nosocomial Sars-CoV-2 outbreak with an high attack rate.

    Anello, Paola / Boscolo Cegion, Riccardo / Basso, Andrea / Cabbia, Chiara / Azzolini, Francesca / Crimi, Luciano / Ruggiero, Myriam / Carraro, Mara / Mazzon, Stefano / Marchiori, Milvia

    Igiene e sanita pubblica

    2023  Volume 80, Issue 5, Page(s) 110–117

    Abstract: Throughout the current COVID-19 pandemic, preventing nosocomial COVID-19 outbreaks has been a significant challenge for hospitals. It is essential to understand the ways in which SARS-CoV-2 spreads in healthcare settings to apply proper infection ... ...

    Abstract Throughout the current COVID-19 pandemic, preventing nosocomial COVID-19 outbreaks has been a significant challenge for hospitals. It is essential to understand the ways in which SARS-CoV-2 spreads in healthcare settings to apply proper infection prevention and control (IPC) measures. The objectives of this study are to report on the hospital's response to a COVID-19 cluster and the transmission dynamics in a hospital ward of Geriatrics, Rehabilitation and Long term care. The study will focus specifically on how insufficient air replacement and directional airflow in indoor settings may have contributed to the transmission of the virus.
    MeSH term(s) Humans ; SARS-CoV-2 ; COVID-19 ; Cross Infection/epidemiology ; Cross Infection/prevention & control ; Incidence ; Pandemics ; Respiratory Aerosols and Droplets ; Disease Outbreaks ; Hospitals
    Language English
    Publishing date 2023-12-15
    Publishing country Italy
    Document type Journal Article
    ZDB-ID 3031485-9
    ISSN 0019-1639
    ISSN 0019-1639
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Artificial Intelligence Decision Support for Medical Triage.

    Marchiori, Chiara / Dykeman, Douglas / Girardi, Ivan / Ivankay, Adam / Thandiackal, Kevin / Zusag, Mario / Giovannini, Andrea / Karpati, Daniel / Saenz, Henri

    AMIA ... Annual Symposium proceedings. AMIA Symposium

    2021  Volume 2020, Page(s) 793–802

    Abstract: Applying state-of-the-art machine learning and natural language processing on approximately one million of teleconsultation records, we developed a triage system, now certified and in use at the largest European telemedicine provider. The system ... ...

    Abstract Applying state-of-the-art machine learning and natural language processing on approximately one million of teleconsultation records, we developed a triage system, now certified and in use at the largest European telemedicine provider. The system evaluates care alternatives through interactions with patients via a mobile application. Reasoning on an initial set of provided symptoms, the triage application generates AI-powered, personalized questions to better characterize the problem and recommends the most appropriate point of care and time frame for a consultation. The underlying technology was developed to meet the needs for performance, transparency, user acceptance and ease of use, central aspects to the adoption of AI-based decision support systems. Providing such remote guidance at the beginning of the chain of care has significant potential for improving cost efficiency, patient experience and outcomes. Being remote, always available and highly scalable, this service is fundamental in high demand situations, such as the current COVID-19 outbreak.
    MeSH term(s) Algorithms ; Artificial Intelligence ; COVID-19/epidemiology ; COVID-19/prevention & control ; Decision Support Systems, Management ; Expert Systems ; Humans ; Remote Consultation ; SARS-CoV-2 ; Telemedicine ; Triage
    Language English
    Publishing date 2021-01-25
    Publishing country United States
    Document type Journal Article
    ISSN 1942-597X
    ISSN (online) 1942-597X
    Database MEDical Literature Analysis and Retrieval System OnLINE

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