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排序方式: 共有383条查询结果,搜索用时 15 毫秒
81.
Máté Szabados Zsófia Csákó Bohumil Kotlík Helena Kazmarová Anna Kozajda Anja Jutraz Andreja Kukec Peter Otorepec Arianna Dongiovanni Andrea Di Maggio Stefano Fraire Tamás Szigeti 《Indoor air》2021,31(4):989-1003
The indoor air quality (IAQ) was investigated in sixty-four primary school buildings in five Central European countries (Czech Republic, Hungary, Italy, Poland, and Slovenia). The concentration of volatile organic compounds, aldehydes, PM2.5 mass, carbon dioxide, radon, as well as physical parameters were investigated during the heating period of 2017/2018. Significant differences were identified for the majority of the investigated IAQ parameters across the countries. The median indoor/outdoor ratios varied considerably. A comprehensive evaluation of IAQ in terms of potential health effects and comfort perception was performed. Hazard quotient values were below the threshold value of 1 with one exception. In contrast, 31% of the school buildings were characterized by hazard index values higher than 1. The maximum cumulative ratio approach highlighted that the concern for non-carcinogenic health effects was either low or the health risk was driven by more substances. The median excess lifetime cancer risk values exceeded the acceptable value of 1 × 10−6 in the case of radon and formaldehyde. PM2.5 mass concentration values exceeded the 24 h and annual guideline values set by the World Health Organization in 56 and 85% of the cases, respectively. About 80% of the schools could not manage to comply with the recommended concentration value for carbon dioxide (1000 ppm). 相似文献
82.
83.
Adele Chimento Anna Santarsiero Domenico Iacopetta Jessica Ceramella Arianna De Luca Vittoria Infantino Ortensia Ilaria Parisi Paola Avena Maria Grazia Bonomo Carmela Saturnino Maria Stefania Sinicropi Vincenzo Pezzi 《International journal of molecular sciences》2021,22(10)
Resveratrol (RSV) is a natural compound that displays several pharmacological properties, including anti-cancer actions. However, its clinical application is limited because of its low solubility and bioavailability. Here, the antiproliferative and anti-inflammatory activity of a series of phenylacetamide RSV derivatives has been evaluated in several cancer cell lines. These derivatives contain a monosubstituted aromatic ring that could mimic the RSV phenolic nucleus and a longer flexible chain that could confer a better stability and bioavailability than RSV. Using MTT assay, we demonstrated that most derivatives exerted antiproliferative effects in almost all of the cancer cell lines tested. Among them, derivative 2, that showed greater bioavailability than RSV, was the most active, particularly against estrogen receptor positive (ER+) MCF7 and estrogen receptor negative (ER-) MDA-MB231 breast cancer cell lines. Moreover, we demonstrated that these derivatives, particularly derivative 2, were able to inhibit NO and ROS synthesis and PGE2 secretion in lipopolysaccharide (LPS)-activated U937 human monocytic cells (derived from a histiocytoma). In order to define the molecular mechanisms underlying the antiproliferative effects of derivative 2, we found that it determined cell cycle arrest at the G1 phase, modified the expression of cell cycle regulatory proteins, and ultimately triggered apoptotic cell death in both breast cancer cell lines. Taken together, these results highlight the studied RSV derivatives, particularly derivative 2, as promising tools for the development of new and more bioavailable derivatives useful in the treatment of breast cancer. 相似文献
84.
Natalia Brossard Beatriz Gonzalez-Muñoz Carolina Pavez Arianna Ricci Xinmiao Wang Fernando Osorio Edmundo Bordeu Giuseppina Paola Parpinello Jianshe Chen 《International Journal of Food Science & Technology》2021,56(10):5382-5394
Astringency is a sensory attribute, related to the quality and mouthfeel of red wines. However, the origin of astringency sub-qualities, such as the typical drying astringency found in immature grapes, is still unknown. Astringency of red wines with similar tannin content but different astringency sub-qualities, from different harvest dates, is studied. Astringency was characterised in terms of friction coefficient, polyphenol content, sensory analysis and tannin/salivary–proteins aggregates characterisation. A different evolution during ripening was found for both Cabernet Sauvignon and Carménère, and tannin–protein aggregates showed differences in size, shape and surface. The velvety sub-quality appears to be related to aggregates with low precipitation, and with specific surface characteristics as roundness and Feret diameter. Results from this work propose an effect of aggregates on sensory perception and opens the possibility to explore their effect on oral lubrication. 相似文献
85.
Arianna Zanoni Cora Casiraghi Riccardo Po Paolo Biagini Mattia Sponchioni Davide Moscatelli 《大分子材料与工程》2023,308(1):2200443
Redispersible polymer powders (RDPPs), i.e., additives obtained from core–shell nanoparticles and commercialized in the form of a dry powder, find intensive application in the concrete industry. However, they are mainly produced from fossil resources. Therefore, the development of bio-based RDPPs is important to reduce the carbon footprint of these additives. In this work, two types of core–shell nanoparticles with a high percentage of bio-based content are synthesized and show to be good candidates as RDPPs. In the first case, up to 75% of bio-based content is obtained by combining lauryl acrylate, derived from coconut and palm kernel oil, as main core material, with isobornyl methacrylate, coming from pine resin, exploited to create the outer harder shell. In the second case, a degradable macromonomer obtained by the ring opening polymerization of lactide using 2-hydroxyethyl methacrylate as initiator is used as the core-forming monomer to obtain degradable RDPPs. In both cases, the particles are synthesized with a two-step emulsion polymerization process conducted in one pot and then spray-dried to obtain the RDPPs of interest. The morphology and redispersibility of the powders are characterized. Finally, their use as concrete additives is preliminarily assessed by evaluating their effect on changes in the surface morphologies of concrete specimens. 相似文献
86.
Alessia Tonoli Karla Wagner Arianna Bacchin Tamara Reiter Prof. Dr. Elisabetta Bergantino Dr. Marina S. Robescu Prof. Dr. Mélanie Hall 《Chembiochem : a European journal of chemical biology》2023,24(9):e202300146
The formal asymmetric and stereodivergent enzymatic reduction of α-angelica lactone to both enantiomers of γ-valerolactone was achieved in a one-pot cascade by uniting the promiscuous stereoselective isomerization activity of Old Yellow Enzymes with their native reductase activity. In addition to running the cascade with one enzyme for each catalytic step, a bifunctional isomerase-reductase biocatalyst was designed by fusing two Old Yellow Enzymes, thereby generating an unprecedented case of an artificial enzyme catalyzing the reduction of nonactivated C=C bonds to access (R)-valerolactone in overall 41 % conversion and up to 91 % ee. The enzyme BfOYE4 could be used as single biocatalyst for both steps and delivered (S)-valerolactone in up to 84 % ee and 41 % overall conversion. The reducing equivalents were provided by a nicotinamide recycling system based on formate and formate dehydrogenase, added in a second step. This enzymatic system provides an asymmetric route to valuable chiral building blocks from an abundant bio-based chemical. 相似文献
87.
Arianna Giacomini Sara Taranto Sara Rezzola Sara Matarazzo Elisabetta Grillo Mattia Bugatti Alessia Scotuzzi Jessica Guerra Martina Di Trani Marco Presta Roberto Ronca 《International journal of molecular sciences》2020,21(24)
Lung cancer represents an extremely diffused neoplastic disorder with different histological/molecular features. Among the different lung tumors, non-small-cell lung cancer (NSCLC) is the most represented histotype, characterized by various molecular markers, including the expression/overexpression of the fibroblast growth factor receptor-1 (FGFR1). Thus, FGF/FGFR blockade by tyrosine kinase inhibitors (TKi) or FGF-ligand inhibitors may represent a promising therapeutic approach in lung cancers. In this study we demonstrate the potential therapeutic benefit of targeting the FGF/FGFR system in FGF-dependent lung tumor cells using FGF trapping (NSC12) or TKi (erdafitinib) approaches. The results show that inhibition of FGF/FGFR by NSC12 or erdafitinib induces apoptosis in FGF-dependent human squamous cell carcinoma NCI-H1581 and NCI-H520 cells. Induction of oxidative stress is the main mechanism responsible for the therapeutic/pro-apoptotic effect exerted by both NSC12 and erdafitinib, with apoptosis being abolished by antioxidant treatments. Finally, reduction of c-Myc protein levels appears to strictly determine the onset of oxidative stress and the therapeutic response to FGF/FGFR inhibition, indicating c-Myc as a key downstream effector of FGF/FGFR signaling in FGF-dependent lung cancers. 相似文献
88.
Arianna Borrelli 《Centaurus; international magazine of the history of science and medicine》2020,62(3):406-424
In this paper, I suggest that research results from the history and philosophy of modern science provide a valuable methodological contribution for investigating early modern experimental philosophy and employ them to reassess the contribution of Giovan Battista Della Porta to its development. In modern science, the production of experimental knowledge is dependent on a complex array of communication strategies involving verbal terminology, diagrams, standardized instruments, and measurement units. Historians and philosophers have investigated the constitutive connection between such strategies and the phenomena scientists study in laboratories, showing how the two often co-evolved during the 19th and 20th centuries. Della Porta took an important first step towards the development of such methods by transforming the traditional recipe format into a strategy for mutually connecting, conceptualizing, and sharing observations made in experiments involving similar, but not identical, instruments and procedures. I use as a case study the changing manner in which he used recipes for presenting and connecting a number of pneumatic experiences from the first edition of Natural Magic (1558) until his meteorology treatise On Transmutations of Air (1610). In modern terms, those experiences can be interpreted as demonstrating the air's expansion and contraction with heat or pressure. However, today's notions of air pressure, density, and volume did not exist around 1600 and the verbal, visual, and quantitative means of expressing them had yet to be created. Della Porta did not create the modern notions, but he contributed to their emergence in a substantial way with his discussions of those pneumatic experiences. Della Porta's innovation may be described as the creation of a new epistemic genre, but it was not of a purely literary character, since the recipes also shaped the instruments and procedures they described, transforming them into new means of knowledge production in experimental philosophy. 相似文献
89.
S Lantuejoul D Moro RJ Michalides C Brambilla E Brambilla 《Canadian Metallurgical Quarterly》1998,22(10):1267-1276
Neural cell adhesion molecules (NCAM) represent specific markers of neuroendocrine (NE) differentiation in lung cancer. Because the polysialic acid form (NCAM-PSA) has reduced adhesion properties, we hypothesized that NCAM-PSA expression could favor metastatic spread. Immunostaining of NCAM and NCAM-PSA were therefore compared in 120 NE lung tumors, including 17 typical carcinoids, 3 atypical carcinoids, 30 large cell NE carcinomas and 70 small cell lung carcinomas, as compared with 25 adenocarcinomas and 25 squamous cell carcinomas. Neural cell adhesion molecules were negative in adenocarcinomas and squamous cell carcinomas but were constantly expressed in all NE tumors from typical carcinoids to small cell lung carcinomas. NCAM-PSA expression was significantly more frequent in high-grade tumors, with 24 of 30 positive cases in large cell NE carcinomas and 65 of 70 positive cases in small cell lung carcinoma, than in carcinoids with 10 of 17 and 2 of 3 positive cases in typical carcinoids and atypical carcinoids, respectively. The neural cell adhesion molecule-polysialic acid form scores of staining were significantly higher in high-grade as compared with low-grade tumors (p = 0.002), and were correlated with nodal spread (p = 0.04) and metastasis (p = 0.016) across histologic classes but not in individual tumor type. We conclude that NCAM-PSA connotes poor differentiation and aggressive clinical behavior in the spectrum of NE lung tumors, but cannot be regarded as a prognostic factor in individual tumor classes. 相似文献
90.