72 research outputs found

    Electrical, mechanical and electromechanical properties of graphene-thermoset polymer composites produced using acetone-DMF solvents

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    Recently, graphene-polymer composites gained a central role in advanced stress and strain sensing. A fundamental step in the production of epoxy-composites filled with graphene nanoplatelets (GNPs) consists in the exfoliation and dispersion of expanded graphite in a proper solvent, in the mixing of the resulting GNP suspension with the polymer matrix, and in the final removal of the solvent from the composite before curing through evaporation. The effects of traces of residual solvent on polymer curing process are usually overlooked, even if it has been found that even a small amount of residual solvent can affect the mechanical properties of the final composite. In this paper, we show that residual traces of N,N′-Dimethylformamide (DMF) in vinylester epoxy composites can induce relevant variations of the electrical, mechanical and electromechanical properties of the cured GNP-composite. To this purpose, a complete analysis of the morphological and structural characteristics of the composite samples produced using different solvent mixtures (combining acetone and DMF) is performed. Moreover, electrical, mechanical and electromechanical properties of the produced composites are assessed. In particular, the effect on the piezoresistive response of the use of DMF in the solvent mixture is analyzed using an experimental strain dependent percolation law to fit the measured electromechanical data. It is shown that the composites realized using a higher amount of DMF are characterized by a higher electrical conductivity and by a strong reduction of Young’s Modulus

    Electromagnetic and electromechanical applications of graphene-based materials

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    This volume contains the extended abstracts of the contributions presented at the workshop Nanoscale Excitations in Emergent Materials (NEEM 2015) held in Rome from 12 to 14 October 2015, an event organized and supported in the framework of the Bilateral Cooperation Agreement between Italy and India within the project of major relevance "Investigating local structure and magnetism of cobalt nano-structures", funded by the Italian Ministry of Foreign Affairs and the Department of Science and Technology in India

    Malignant pleural mesothelioma and mesothelial hyperplasia: A new molecular tool for the differential diagnosis

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    Malignant pleural mesothelioma (MPM) is a rare asbestos related cancer, aggressive and unresponsive to therapies. Histological examination of pleural lesions is the gold standard of MPM diagnosis, although it is sometimes hard to discriminate the epithelioid type of MPM from benign mesothelial hyperplasia (MH). This work aims to define a new molecular tool for the differential diagnosis of MPM, using the expression profile of 117 genes deregulated in this tumour. The gene expression analysis was performed by nanoString System on tumour tissues from 36 epithelioid MPM and 17 MH patients, and on 14 mesothelial pleural samples analysed in a blind way. Data analysis included raw nanoString data normalization, unsupervised cluster analysis by Pearson correlation, non-parametric Mann Whitney U-test and molecular classification by the Uncorrelated Shrunken Centroid (USC) Algorithm. The Mann-Whitney U-test found 35 genes upregulated and 31 downregulated in MPM. The unsupervised cluster analysis revealed two clusters, one composed only of MPM and one only of MH samples, thus revealing class-specific gene profiles. The Uncorrelated Shrunken Centroid algorithm identified two classifiers, one including 22 genes and the other 40 genes, able to properly classify all the samples as benign or malignant using gene expression data; both classifiers were also able to correctly determine, in a blind analysis, the diagnostic categories of all the 14 unknown samples. In conclusion we delineated a diagnostic tool combining molecular data (gene expression) and computational analysis (USC algorithm), which can be applied in the clinical practice for the differential diagnosis of MPM

    Low elasticity of thyroid nodules at ultrasound elastography is correlated with malignancy, degree of fibrosis and high expression of galectin-3 and fibronectin-1

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    ackground: Thyroid ultrasound (US) elastography provides an estimation of tissue stiffness and is helpful to differentiate malignant from benign lesions. Tissue proprieties and molecules causing stiffness are not established. The aim of the study was to correlate US elastography findings with tissue properties in thyroid nodules. Methods: A total of 115 thyroid nodules from 112 patients who underwent surgery for the presence of Thy 3 (indeterminate) cytology (n = 67), Thy 4-5 (suspicious - indicative of carcinoma) cytology (n = 47), or large goiter in the presence of Thy 2 cytology (n = 1) and suspicious US features were examined by US elastography. Tissues obtained after surgery were characterized for cell number, microvessel density, fibrosis, and expression of galectin-3 (Gal-3) and fibronectin-1 (FN-1). Results: Low elasticity on qualitative US elastography (LoEl) was found in 66 nodules (one benign and 65 carcinomas); high elasticity (HiEl) was found in 49 nodules (46 benign and three carcinomas; p < 0.0001). Quantitative analysis, performed in 24 nodules and expressed as elastic ratio between the strain of the nodule and that of the surrounding thyroid parenchyma, showed a mean of 1.90 (interquartile range [IQR] 1.18-2.77) in 14 nodules with LoEl, and a mean of 1.01 (IQR 0.91-1.10) in 10 nodules with HiEl (p = 0.002). Stiffness did not correlate with cell number and was inversely correlated with microvessel density. Fibrosis was higher in nodules with LoEl than in those with HiEl (p = 0.009) and in carcinomas than in benign nodules (p = 0.02). Fibrosis was higher in nodules with high expression of Gal-3 (p < 0.001) and FN-1 (p = 0.004). Fibrosis and expression of Gal-3 and FN-1 were higher in the classic compared with the follicular variant of papillary thyroid carcinoma and lower in follicular adenomas. Conclusions: Low elasticity at US elastography is highly correlated with malignancy. Nodule stiffness is correlated with fibrosis and expression of Gal-3 and FN-1. These features are more evident in the classic than in the follicular variant of papillary thyroid carcinoma

    ALK rearrangement in a large series of consecutive non-small cell lung cancers: Comparison between a new immunohistochemical approach and fluorescence in situ hybridization for the screening of patients eligible for crizotinib treatment

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    Context. - Echinoderm microtubule associated protein-like 4-anaplastic lymphoma receptor tyrosine kinase (EML4-ALK) translocation has been described in a subset of patients with non-small cell lung cancer (NSCLC) and has been shown to have oncogenic activity. Fluorescence in situ hybridization (FISH) is used to detect ALK-positive NSCLC, but it is expensive, time-consuming, and difficult for routine application. Objective. - To evaluate the potential role of immunohistochemistry (IHC) as a screening tool to identify candidate cases for FISH analysis and for ALK inhibitor therapy in NSCLC. Design. - We performed FISH and IHC for ALK and mutational analysis for epidermal growth factor receptor (EGFR) and KRAS in 523 NSCLC specimens. We conducted IHC analysis with the monoclonal antibody D5F3 (Ventana Medical Systems, Tucson, Arizona) and a highly sensitive detection system. We also performed a MassARRAY-based analysis (Sequenom, San Diego, California) in a small subset of 11 samples to detect EML4-ALK rearrangement. Results. - Of the 523 NSCLC specimens, 20 (3.8%) were positive for ALK rearrangement by FISH analysis. EGFR and KRAS mutations were identified in 70 (13.4%) and 124 (23.7%) of the 523 tumor samples, respectively. ALK rearrangement and EGFR and KRAS mutations were mutually exclusive. Of 523 tumor samples analyzed, 18 (3.4%) were ALK+ by IHC, 18 samples (3.4%) had concordant IHC and FISH results, and 2 ALK+ cases (0.3%) by FISH failed to show ALK protein expression. In the 2 discrepant cases, we did not detect any mass peaks for the EML4-ALK variants by MassARRAY. Conclusions. - Our results show that IHC may be a useful technique for selecting NSCLC cases to undergo ALK FISH analysis

    Proteomic approach used in the diagnosis of Riedel's thyroiditis: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Riedel's thyroiditis, a rare thyroid disease, can be difficult to diagnose prior to surgical removal and can be confused with malignancy both clinically and cytologically.</p> <p>Case presentation</p> <p>We report the case of a 72-year-old Caucasian woman who presented with a goiter, which showed a rapid increase in size at ultrasound check, suggesting malignancy. Because of inconclusive cytology, a total thyroidectomy was performed. Fine-needle aspiration of the removed thyroid was processed by two-dimensional electrophoresis, and the proteome was compared with both anaplastic cancer and control samples. Significant differentially expressed protein spots were identified by Western blot analysis by using specific antibodies.</p> <p>Conclusions</p> <p>The protein pattern of Riedel's fine-needle aspiration revealed a superimposition with that of the control samples. The comparison of the protein pattern of Riedel's thyroiditis fine-needle aspiration with that of anaplastic cancer showed evidence of a different expression of ferritin heavy chains, ferritin light chains, and haptoglobins, as previously reported in thyroid cancers. Therefore, we performed Western blot analysis of these proteins and validated that their expression levels were low or absent in Riedel's thyroiditis and control samples despite the high concentrations present in fine-needle aspiration anaplastic samples. The concurrent absent or low expression levels of haptoglobin, ferritin light chain, and ferritin heavy chain in Riedel's thyroiditis fine-needle aspiration samples strongly indicate the benign nature of the thyroid lesion. These results suggest the potential applicability of fine-needle aspiration proteome analysis for Riedel's thyroiditis diagnosis.</p

    Crizotinib in MET-Deregulated or ROS1-Rearranged Pretreated Non-Small Cell Lung Cancer (METROS): A Phase II, Prospective, Multicenter, Two-Arms Trial.

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    PURPOSE: MET-deregulated NSCLC represents an urgent clinical need because of unfavorable prognosis and lack of specific therapies. Although recent studies have suggested a potential role for crizotinib in patients harboring MET amplification or exon 14 mutations, no conclusive data are currently available. This study aimed at investigating activity of crizotinib in patients harboring MET or ROS1 alterations. PATIENTS AND METHODS: Patients with pretreated advanced NSCLC and evidence of ROS1 rearrangements (cohort A) or MET deregulation (amplification, ratio MET/CEP7 &gt;2.2 or MET exon 14 mutations, cohort B) were treated with crizotinib 250 mg twice daily orally. The coprimary endpoint was objective response rate in the two cohorts. RESULTS: From December 2014 to March 2017, 505 patients were screened and a total of 52 patients (26 patients per cohort) were enrolled onto the study. At data cutoff of September 2017, in cohort A, objective response rate was 65%, and median progression-free survival and overall survival were 22.8 months [95% confidence interval (CI) 15.2-30.3] and not reached, respectively. In cohort B, objective response rate was 27%, median progression-free survival was 4.4 months (95% CI 3.0-5.8), and overall survival was 5.4 months (95% CI, 4.2-6.5). No difference in any clinical endpoint was observed between MET-amplified and exon 14-mutated patients. No response was observed among the 5 patients with cooccurrence of a second gene alteration. No unexpected toxicity was observed in both cohorts. CONCLUSIONS: Crizotinib induces response in a fraction of MET-deregulated NSCLC. Additional studies and innovative therapies are urgently needed

    The role of immune suppression in COVID-19 hospitalization: clinical and epidemiological trends over three years of SARS-CoV-2 epidemic

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    Specific immune suppression types have been associated with a greater risk of severe COVID-19 disease and death. We analyzed data from patients &gt;17 years that were hospitalized for COVID-19 at the “Fondazione IRCCS Ca′ Granda Ospedale Maggiore Policlinico” in Milan (Lombardy, Northern Italy). The study included 1727 SARS-CoV-2-positive patients (1,131 males, median age of 65 years) hospitalized between February 2020 and November 2022. Of these, 321 (18.6%, CI: 16.8–20.4%) had at least one condition defining immune suppression. Immune suppressed subjects were more likely to have other co-morbidities (80.4% vs. 69.8%, p &lt; 0.001) and be vaccinated (37% vs. 12.7%, p &lt; 0.001). We evaluated the contribution of immune suppression to hospitalization during the various stages of the epidemic and investigated whether immune suppression contributed to severe outcomes and death, also considering the vaccination status of the patients. The proportion of immune suppressed patients among all hospitalizations (initially stable at &lt;20%) started to increase around December 2021, and remained high (30–50%). This change coincided with an increase in the proportions of older patients and patients with co-morbidities and with a decrease in the proportion of patients with severe outcomes. Vaccinated patients showed a lower proportion of severe outcomes; among non-vaccinated patients, severe outcomes were more common in immune suppressed individuals. Immune suppression was a significant predictor of severe outcomes, after adjusting for age, sex, co-morbidities, period of hospitalization, and vaccination status (OR: 1.64; 95% CI: 1.23–2.19), while vaccination was a protective factor (OR: 0.31; 95% IC: 0.20–0.47). However, after November 2021, differences in disease outcomes between vaccinated and non-vaccinated groups (for both immune suppressed and immune competent subjects) disappeared. Since December 2021, the spread of the less virulent Omicron variant and an overall higher level of induced and/or natural immunity likely contributed to the observed shift in hospitalized patient characteristics. Nonetheless, vaccination against SARS-CoV-2, likely in combination with naturally acquired immunity, effectively reduced severe outcomes in both immune competent (73.9% vs. 48.2%, p &lt; 0.001) and immune suppressed (66.4% vs. 35.2%, p &lt; 0.001) patients, confirming previous observations about the value of the vaccine in preventing serious disease

    Ruolo dell’infiltrato infiammatorio nel carcinoma tiroideo

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    L’infiammazione è un processo fisiologico protettivo che l’organismo utilizza in risposta al danno tissutale, innescato dall’azione dannosa di agenti fisici, chimici e biologici, il cui obiettivo finale è l’eliminazione della causa iniziale di danno tissutale o cellulare. L’esistenza di una relazione tra infiammazione cronica e cancro è stata per la prima volta proposta da Virchow nel 1863 ed è stata confermata da evidenze cliniche ed epidemiologiche. In questo studio abbiamo caratterizzato i componenti dell’infiltrato infiammatorio e i fattori proinfiammatori in una serie consecutiva di carcinomi tiroidei differenziati e anaplastici. La loro incidenza è in continuo aumento e l’andamento prognostico di tali neoplasie è duplice, forme differenziate ad evoluzione benigne e forme molto più aggressive. Tale frequenza e tale duplice andamento non sono ancora stati interpretati, potrebbero essere dovuti per esempio all’alterazione dei circuiti di promozione della crescita e della proliferazione, oppure allo sconvolgimento dei normali sistemi di omeostasi tissutale. Ma un ulteriore, affascinante progresso nella comprensione dei meccanismi di sviluppo delle neoplasie umane è stato compiuto con l’individuazione del contributo delle cellule infiammatorie presenti nel tessuto tumorale alla produzione di fattori di crescita, di fattori pro-angiogenetici, di citochine ed enzimi litici che favoriscono la proliferazione e le capacità invasive delle cellule neoplastiche. Quindi il nostro studio verterà sulla caratterizzazione di alcuni componenti dell’infiltrato infiammatorio correlato alla neoplasia mediante l’utilizzo di anticorpi diretti verso i macrofagi e i mastociti, e sulla determinazione dell’espressione tramite immunoistochimica di alcune chemochine (CXCL10/IP10, CXCL1/GRO-α, CCL2/MCP1) coinvolte nella chemotassi delle cellule infiammatorie sopramenzionate e a loro volta elementi di congiunzione tra alterazioni molecolari cardine dello sviluppo del carcinoma papillare, come la mutazione di BRAF, e l’infiammazione cronica tumore associata. Valuteremo inoltre la presenza di una correlazione tra l’espressione di questi elementi, i fattori clinico-patologici e la presenza e intensità della tiroidite. Infine verificheremo l’esistenza di una relazione tra il grado di espressione di tali proteine e la quantità di mRNA prodotto dalle cellule tumorali. Inoltre cercheremo la correlazione tra lo stato mutazionale dei carcinomi tiroidei analizzati e l’espressione delle tre chemochine selezionate
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