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151.
Benedetta Ferrara Erica Dugnani Valeria Sordi Valentina Pasquale Silvia Pellegrini Michele Reni Gianpaolo Balzano Lorenzo Piemonti 《International journal of molecular sciences》2022,23(18)
The aim of this study is to provide a comprehensive characterization of stemness in pancreatic ductal adenocarcinoma (PDAC) cell lines. Seventeen cell lines were evaluated for the expression of cancer stem cell (CSC) markers. The two putative pancreatic CSC phenotypes were expressed heterogeneously ranging from 0 to 99.35% (median 3.46) for ESA+CD24+CD44+ and 0 to 1.94% (median 0.13) for CXCR4+CD133+. Cell lines were classified according to ESA+CD24+CD44+ expression as: Low-Stemness (LS; <5%, n = 9, median 0.31%); Medium-Stemness (MS; 6–20%, n = 4, median 12.4%); and High-Stemness (HS; >20%, n = 4, median 95.8%) cell lines. Higher degree of stemness was associated with in vivo tumorigenicity but not with in vitro growth kinetics, clonogenicity, and chemo-resistance. A wide characterization (chemokine receptors, factors involved in pancreatic organogenesis, markers of epithelial–mesenchymal transition, and secretome) revealed that the degree of stemness was associated with KRT19 and NKX2.2 mRNA expression, with CD49a and CA19.9/Tie2 protein expression, and with the secretion of VEGF, IL-7, IL-12p70, IL-6, CCL3, IL-10, and CXCL9. The expression of stem cell markers was also evaluated on primary tumor cells from 55 PDAC patients who underwent pancreatectomy with radical intent, revealing that CXCR4+/CD133+ and CD24+ cells, but not ESA+CD24+CD44+, are independent predictors of mortality. 相似文献
152.
153.
Lorenza Pastorino Bruna Dalmasso Eleonora Allavena Irene Vanni Filippo Ugolini Gianna Baroni Michela Croce Antonio Guadagno Francesco Cabiddu Virginia Andreotti William Bruno Gabriele Zoppoli Lorenzo Ferrando Enrica Teresa Tanda Francesco Spagnolo Chiara Menin Rosaria Gangemi Daniela Massi Paola Ghiorzo 《International journal of molecular sciences》2022,23(24)
ATM germline pathogenic variants were recently found enriched in high-risk melanoma patients. However, ATM loss of heterozygosity (LOH) has never been investigated in melanoma and, therefore, a causal association with melanoma development has not been established yet. The purpose of this study was to functionally characterize 13 germline ATM variants found in high-risk melanoma patients—and classified by in silico tools as pathogenic, uncertain significance, or benign—using multiple assays evaluating ATM/pATM expression and/or LOH in melanoma tissues and cell lines. We assessed ATM status by Immunohistochemistry (IHC), Western Blot, Whole-Exome Sequencing/Copy Number Variation analysis, and RNA sequencing, supported by Sanger sequencing and microsatellite analyses. For most variants, IHC results matched those obtained with in silico classification and LOH analysis. Two pathogenic variants (p.Ser1135_Lys1192del and p.Ser1993ArgfsTer23) showed LOH and complete loss of ATM activation in melanoma. Two variants of unknown significance (p.Asn358Ile and p.Asn796His) showed reduced expression and LOH, suggestive of a deleterious effect. This study, showing a classic two-hit scenario in a well-known tumor suppressor gene, supports the inclusion of melanoma in the ATM-related cancer spectrum. 相似文献
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155.
Maria Paula Junqueira-Gonçalves Erica Alarcón Keshavan Niranjan 《Food and Bioprocess Technology》2014,7(9):2610-2617
This study proposes to incorporate an antifungal agent (potassium sorbate, KS) to post-consumer recycled polyethylene terephthalate (PCRPET), by adding KS to the dip solution through which PCRPET normally passes after extrusion, in order to acquire a non-stick silicone coating, which prevents individual packages from adhering to each other while stacked. This method of imparting antifungal activity to the packaging is far more advantageous than adding KS to the extruder feed because it results in virtually no alterations to the colour and mechanical properties of PCRPET, which is a major issue when KS is added to the extruder feed. The antifungal efficacy of the active packaging was demonstrated against Botrytis cinerea growth by a novel method which mimics the action of the antifungal agent under fruit contact conditions. A reduction by 2 log cycles was observed when the initial concentration of the mould was 105 conidia/mL. The active packaging was effective over a test period lasting 6 months. The packaging microstructure was visualized by scanning electron microscopy (SEM); its thermal properties were characterized using a differential scanning calorimeter (DSC); its optical properties were characterized using CIE Lab colorimetry; and its mechanical properties were characterized by measuring resistance to dynamic compression. The mechanical properties showed no significant difference (P?>?0.05) with those of the control (PCRPET without KS), and despite a statistically significant difference (P?<?0.05) in the colour parameters (L*, a* and b*), the total colour difference (ΔE*) was found to be too small to be visually noticed. This study achieved the aim of adding antifungal activity to PCRPET packaging with little or no perceptible changes to its mechanical, thermal and optical properties and virtually no changes being made to the standard high-speed packaging production line. 相似文献
156.
Leonardo Orazi Erica Liverani Alessandro Ascari Alessandro Fortunato Luca Tomesani 《CIRP Annals》2014,63(1):233-236
A new process, based on ring spot geometry, is presented for laser surface hardening of large cylindrical components. The proposed technique leads to a very hard, deep and uniform hardened layer along the entire work piece surface without introducing a tempered zone, making the process very attractive compared to conventional induction hardening that exhibits both low energy efficiency and poor flexibility. A complete physical model is presented for the process, together with a study of the influence of process parameters on the final outcome. The results of an extensive validation campaign, carried out on AISI 1040 specimens, are also reported. 相似文献
157.
Mobility, in broad terms, includes everything from the ability to move within your immediate environment (e.g., get out of bed) to the ability to drive across the country. Mobility is essential to maintaining independence and wellbeing, particularly for older adults. This is highlighted by the large number of interventions developed for older adults with the goal of maintaining such mobility. The current paper reviews the state of the science with respect to mobility interventions. Inclusion criteria for the review were: (1) articles must have been peer-reviewed; (2) interventions were evaluated in a randomized controlled trial (RCT); (3) studies included a mobility outcome such as lifespace, driving, or walking ability; (4) studies included a sample of healthy community-dwelling older adults (e.g., not investigations of disease conditions); and (5) studies must have reported enough empirical data and detail such that results could potentially be replicated. Three main types of interventions were identified: cognitive training, educational interventions, and exercise interventions. A detailed summary and evaluation of each type of intervention, and the current evidence regarding its effectiveness in maintaining mobility, are discussed. Several interventions show clear evidence of effectiveness, and thus are prime areas for translation of results to the older population. Needs and issues for future intervention research are also detailed. 相似文献
158.
Camila F.N. Silva Angélica M. Lazarin Rosana L. Sernaglia Elza I.S. Andreotti 《Materials Research Bulletin》2012,47(6):1539-1543
Crystalline lamellar calcium phosphate retained 4-aminobenzoic acid inside its cavity without leaching. The intense infrared bands in the 1033 and 1010 cm?1 interval confirmed the presence of the phosphonate groups attached to the inorganic layer, with sharp and intense peaks in X-ray diffraction patterns, which gave basal distances of 712 and 1578 pm for the original and the intercalated compounds, respectively. Solid-state 31P nuclear magnetic resonance spectra presented only one peak for the phosphate groups attached to the main inorganic polymeric structure near ?2.4 ppm. The adsorption isotherms from ethanol gave the maximum adsorption capacities of 6.44 and 3.34 mmol g?1 for nickel and cobalt, respectively, which stability constant and distribution coefficient followed Co > Ni. 相似文献
159.
Izabelle S. Rehfeld Ana Luiza S. Fraiha Ana Carolina D. Matos Maria Isabel M.C. Guedes Erica A. Costa Marcelo R. de Souza Luigi F.L. Cavalcante Zélia I.P. Lobato 《Journal of dairy science》2017,100(9):7051-7054
Bovine vaccinia is a neglected zoonosis caused by Vaccinia virus (VACV) and has a major economic and public health effect in Brazil. Previous studies showed infectious VACV particles in milk from either experimentally or naturally infected cows and in fresh cheeses prepared with experimentally contaminated milk. Ripening is a process that leads to major changes in the physical and chemical characteristics of cheese, reducing contamination by spoilage, pathogenic microorganisms, or both. However, it is not known if VACV infectious particles persist after the ripening process. To investigate this issue, viral infectivity at different ripening times was studied in cheeses manufactured with milk experimentally contaminated with VACV strain Guarani P2 (GP2). Cheeses were analyzed at 1, 7, 14, 21, 45, and 60 d of ripening at 25°C. Viral DNA was quantified by real-time PCR, and VACV isolation and titration were performed in Vero cells. The whole experiment was repeated 4 times. Analysis of the mean viral DNA quantification and infectivity indicated a reduction of approximately 2 logs along the ripening process; however, infectious viral particles (1.7 × 102 pfu/mL) could still be recovered at d 60 of ripening. These findings indicate that the ripening process reduces VACV infectivity, but it was not able to inactivate completely the viral particles after 60 d. 相似文献
160.