104 research outputs found
Intravoxel incoherent motion diffusion-weighted imaging for oropharyngeal squamous cell carcinoma: Correlation with human papillomavirus Status
Purpose: To investigate the relationships between imaging parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and HPV status in oropharyngeal squamous cell carcinoma (OPSCC). Materials and Methods: 73 patients with a new diagnosis of OPSCC were enrolled in the present study. MRI including IVIM-DWI with nine b value (range 0â800 s/mm2) was acquired in all patients. Primary tumor (PT) and the largest metastatic lymph node (LN), if present, were volumetrically contoured and the tissue diffusion coefficient Dt, perfusion fraction f and perfusion-related diffusion coefficient D* were estimated by a bi-exponential fit. The apparent diffusion coefficient (ADC) was also estimated by a mono-exponential fit. The predictive power of the most relevant patient/tumor characteristics and image-based features in determining the HPV status was assessed. Results: 67 PTs and 67 metastatic LNs were analyzed. Significant differences in ADC and Dt values among HPV-positive and HPV-negative patients were found for PTs (p = 0.003 and p < 0.001, respectively), while a trend toward significance in Dt was reported for LNs (p = 0.066). The perfusion-related parameters, f, D* and D*Ă f, were not related to HPV status. The best predictive model for HPV positivity was obtained combining alcohol intake and smoke habits with Dt values of PTs (accuracy = 80.8%, sensitivity = 85.7%, specificity = 64.7%). Conclusion: Significant correlations were found between IVIM-DWI and HPV status in OPSCCs. The perfusion-free diffusion coefficient, Dt, may better reflect the HPV-related tumor differences compared to ADC, whereas the perfusion-related parameters were not able to reliably discriminate HPV-positive from HPV-negative OPSCC
Correlation between histogram-based DCEMRI parameters and 18F-FDG PET values in oropharyngeal squamous cell carcinoma: Evaluation in primary tumors and metastatic nodes
Objectives To investigate the correlation between histogram-based Dynamic Contrast-Enhanced magnetic resonance imaging (DCE-MRI) parameters and positron emission tomography with 18F-fluorodeoxyglucose (18F-FDG-PET) values in oropharyngeal squamous cell carcinoma (OPSCC), both in primary tumors (PTs) and in metastatic lymph nodes (LNs). Methods 52 patients with a new pathologically-confirmed OPSCC were included in the present retrospective cohort study. Imaging including DCE-MRI and 18F-FDG PET/CT scans were acquired in all patients. Both PTs and the largest LN, if present, were volumetrically contoured. Quantitative parameters, including the transfer constants, Ktrans and Kep, and the volume of extravascular extracellular space, ve, were calculated from DCE-MRI. The percentiles (P), P10, P25, P50, P75, P90, and skewness, kurtosis and entropy were obtained from the histogram-based analysis of each perfusion parameter. Standardized uptake values (SUV), SUVmax, SUVpeak, SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were calculated applying a SUV threshold of 40%. The correlations between all variables were investigated with the Spearman-rank correlation test. To exclude false positive results under multiple testing, the Benjamini-Hockberg procedure was applied. Results No significant correlations were found between any parameters in PTs, while significant associations emerged between Ktrans and 18F-FDG PET parameters in LNs. Conclusions Evident relationships emerged between DCE-MRI and 18F-FDG PET parameters in OPSCC LNs, while no association was found in PTs. The complex relationships between perfusion and metabolic biomarkers should be interpreted separately for primary tumors and lymph-nodes. A multiparametric approach to analyze PTs and LNs before treatment is advisable in head and neck squamous cell carcinoma (HNSCC)
Italian patients with hemoglobinopathies exhibit a 5-fold increase in age-standardized lethality due to SARS-CoV-2 infection.
Since the beginning of the COVID-19 pandemic, concerns have been expressed worldwide for patients with hemoglobinopathies and their vulnerability to SARS-CoV-2 infection. Data from Lebanon confirmed a role of underlying comorbidities on COVID-19 severity, but no deaths among a cohort of thalassemia patients.1 Patients with sickle cell disease (SCD) displayed a broad range of severity after SARS-CoV-2 infection, spanning from a favorable outcome unless pre-existing comorbidities (UK cohort)2 to high case mortality in US.3 History of pain, heart, lung, and renal comorbidities was identified as risk factors of worse COVID-19 outcomes by the US SECURE-SCD Registry.4 While Italy experienced a death rate in the general population among the highest in the world, preliminary data from the first wave of the pandemic showed a lower than expected number of infected thalassemia patients (updated up to April 10, 2020), likely due to earlier and more vigilant self-isolation compared to the general population.
Treatments of asbestos containing wastes
Since the second half of the twentieth century, many studies have indicated inhalation of asbestos fibers as the main cause of deadly diseases including fibrosis and cancer. Consequently, since the beginning of the 80s, many countries started banning production and use of asbestos containing products (ACP), although still present in private and public buildings. Due to some extraordinary catastrophic events and/or the aging of these products, people's health and environmental risk associated with the inhalation of asbestos fibers keeps being high even in those countries where it was banned. For these reasons, many communities are developing plans for an environmental and sanitary safe asbestos removal and management. Asbestos containing wastes (ACW) are usually disposed in controlled landfills, but this practice does not definitively eliminate the problems related with asbestos fiber release and conflicts with the ideas of sustainable land use, recycling, and closing material cycles. Consequently, many scientific papers and patents proposed physical, chemical, and biological treatments aimed to the detoxification of ACW (or the reduction of their health effects) and looking for the adoption of technologies, which allow the reuse of the end-products. By including recent relevant bibliography, this report summarizes the status of the most important and innovative treatments of ACW, providing main operating parameters, advantages, and disadvantages
Evaluating Adversarial Attacks and Defences in Infrared Deep Learning Monitoring Systems
This paper studies adversarial attacks and defences against deep learning models trained on infrared data to classify the presence of humans and detect their bounding boxes, which differently from the standard RGB case is an open research problem with multiple consequences related to safety and secure artificial intelligence applications. The paper has two major contributions. Firstly, we study the effectiveness of the Projected Gradient Descent (PGD) adversarial attack against Convolutional Neural Networks (CNNs) trained exclusively on infrared data, and the effectiveness of adversarial training as a possible defense against the attack. Secondly, we study the response of an object detection model trained on infrared images under adversarial attacks. In particular, we propose and empirically evaluate two attacks: one classical attack from the literature on object detection, and a new hybrid attack which exploits a common CNN base architecture of the classifier and the object detector. We show for the first time that adversarial attacks weaken the performance of classification and detection models trained on infrared images only. We also prove that the defense adversarial training optimized for the infinity norm increases the robustness of different classification models trained on infrared data
Setting for ânormalâ serum ferritin levels in patients with transfusionâdependent thalassemia: Our current strategy
This crossâsectional study aimed to establish the association between serum ferritin levels and organ iron overload (IO) and overall morbidity in transfusionâdependent thalassemia (TDT) patients. One hundred and three TDT patients (40.03 ± 9.15 years; 57.3% females) with serum ferritin < 2500 ng/mL were included. IO was assessed by T2* magnetic resonance imaging. Three groups were identified based on mean serum ferritin levels: <500 ng/mL (group 0; N = 32), 500â1000 ng/mL (group 1; N = 43), and 1000â2500 ng/mL (group 2; N = 28). All demographic and biochemical parameters were comparable among the three groups, with the exception of the triglycerides being significantly lower in group 0 than in group 2. No difference was found in the frequency of hepatic, endocrine, and cardiac complications. Hepatic IO was significantly less frequent in group 0 versus both groups 1 and 2. No patient with a serum ferritin level < 500 ng/mL had significant myocardial IO and alterations in the main hematological parameters. No difference in the distribution of the different chelation regimens was found. Serum ferritin < 500 ng/mL appears to be achievable and safe for several TDT patients. This target is associated with the absence of significant cardiac iron and significantly lower hepatic IO and triglycerides that are wellâdemonstrated markers for cardiac and liver complications
Sludge minimization in mainstream wastewater treatment: Mechanisms, strategies, technologies, and current development
Excess sludge production in wastewater treatment plants has become an enormous environmental issue worldwide mainly due to the increased efforts towards wastewater purification. Researchers and plant operators are looking for technological solutions to reduce sludge production through the upgrading of existing technologies and configurations or by substituting them with alternative solutions. Several strategies have been identified to reduce sludge production, including the use of biological and physical-chemical methods (or a combination of them) and novel technologies, although many have not been sufficiently tested at full-scale. To select the most suitable system for sludge reduction, understanding the reduction mechanisms, advantages, disadvantages, and the economic and environmental impact of each technology is essential. This work offers a comprehensive and critical overview of mainstream sludge reduction technologies and underlying mechanisms from laboratory to full scale, and describes potential application, configuration, and integration with conventional systems. Research needs are highlighted, and a techno-economic-environmental comparison of the existing technologies is also proposed
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