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661.
Valentina Mikhailova Polina Grebenkina Evgeniia Khokhlova Alina Davydova Zeina Salloum Elizaveta Tyshchuk Valeria Zagainova Kseniia Markova Igor Kogan Sergey Selkov Dmitry Sokolov 《International journal of molecular sciences》2022,23(4)
During pregnancy, uterine NK cells interact with trophoblast cells. In addition to contact interactions, uterine NK cells are influenced by cytokines, which are secreted by the cells of the decidua microenvironment. Cytokines can affect the phenotypic characteristics of NK cells and change their functional activity. An imbalance of pro- and anti-inflammatory signals can lead to the development of reproductive pathology. The aim of this study was to assess the effects of cytokines on NK cells in the presence of trophoblast cells in an in vitro model. We used TNFα, IFNγ, TGFβ and IL-10; the NK-92 cell line; and peripheral blood NK cells (pNKs) from healthy, non-pregnant women. For trophoblast cells, the JEG-3 cell line was used. In the monoculture of NK-92 cells, TNFα caused a decrease in CD56 expression. In the coculture of NK cells with JEG-3 cells, TNFα increased the expression of NKG2C and NKG2A by NK-92 cells. Under the influence of TGFβ, the expression of CD56 increased and the expression of NKp30 decreased in the monoculture. After the preliminary cultivation of NK-92 cells in the presence of TGFβ, their cytotoxicity increased. In the case of adding TGFβ to the PBMC culture, as well as coculturing PBMCs and JEG-3 cells, the expression of CD56 and NKp44 by pNK cells was reduced. The differences in the effects of TGFβ in the model using NK-92 cells and pNK cells may be associated with the possible influence of monocytes or other lymphoid cells from the mononuclear fraction. 相似文献
662.
Effects of pH variations on anodic marine consortia in a dual chamber microbial fuel cell 总被引:1,自引:0,他引:1
Valentina Margaria Tonia Tommasi Simona Pentassuglia Valeria Agostino Adriano Sacco Caterina Armato Angelica Chiodoni Tiziana Schilirò Marzia Quaglio 《International Journal of Hydrogen Energy》2017,42(3):1820-1829
The effect of anodic pH on Microbial fuel cells (MFCs) inoculated with marine consortia was investigated to characterize the microbial community adaptation to possible pH environmental changes and to define the pH extreme boundaries beyond which MFCs do not run properly.Tests were conducted in triplicate using different feeding pH values (pHfeed) ranging from 3 to 13. The MFCs inoculated with marine consortia had a strong self-regulation ability and actively counterbalanced small variations in pHfeed maintaining the pH inside the anodic chamber (pHanode) close to neutrality.As soon as the pHanode deviated from neutrality it affected MFCs' performances. Alkaline conditions with pHanode values between 8 and 10 corresponded to the formation of a denser biofilm together with the best performance in terms of maximum power density (Pmax). Conversely, when the pHanode reached values lower than 5.5 or higher than 10, a sharp drop in MFC performances, as well as a decrease of viable population, were observed. Interestingly, the system was able to survive these extreme conditions and restart working effectively when neutrality was reset.The obtained results underline the high adaptability and recovery ability of anodic marine consortia even in extreme conditions, suggesting the employment of this inoculum for MFC applications as biosensors for on-site seawater monitoring or as power supply units to be installed in remote area. 相似文献
663.
Nicola Mazzocca Antonella Santone Gigliola Vaglini Valeria Vittorini 《Software Testing, Verification and Reliability》2002,12(1):3-21
A system supporting video on demand is modeled in the process calculus CCS (Calculus of Communicating Systems), while some properties are expressed in a temporal logic and verified by means of the model checkers of the North Carolina Concurrency Workbench. This application was chosen as a case study to evaluate the usefulness of a methodology, by means of which a property is checked on reduced models obtained issuing abstractions of the system on the basis of the formula. Experimental results are shown and discussed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
664.
The present investigation is concerned with the evaluation of the impact toughness of commercial‐grade Propylene polymers. Conventional impact static stress–strain and static fracture experiments were carried out. Static stress–strain experiments revealed different pattern behaviors among the materials that were reflected in the fracture behavior. Under static conditions, all materials exhibited ductile behavior and crack grew under J‐controlled conditions displaying stress whitening through the whole fracture surface with the sole exception of the homopolymer, which displayed a ductile instability after some stable crack growth. Under dynamic conditions the homopolymer exhibited brittle behavior, the block copolymer exhibited some plastic deformation at the crack tip, and the random copolymer samples exhibited a whitening effect due to voiding and craze formation through the whole fracture surface, indicating that stable crack propagation was occurring. Fracture mechanics tests were analyzed by following different methods, depending on the mode of fracture presented by the polymer. The Normalization J‐method was used under static conditions. The elastic method, the corrected elastic method, and the essential work of fracture methodology were used to characterize brittle, semibrittle, and ductile behavior, respectively. Fracture mechanics parameters arisen from both static and dynamic conditions are compared. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2681–2693, 1999 相似文献
665.
Michela Terri Nicoletta Mancianti Flavia Trionfetti Bruno Casciaro Valeria de Turris Giammarco Raponi Giulio Bontempi Claudia Montaldo Alessandro Domenici Paolo Men Maria Luisa Mangoni Raffaele Strippoli 《International journal of molecular sciences》2022,23(3)
While blue LED (b-LED) light is increasingly being studied for its cytotoxic activity towards bacteria in therapy of skin-related infections, its effects on eukaryotic cells plasticity are less well characterized. Moreover, since different protocols are often used, comparing the effect of b-LED towards both microorganisms and epithelial surfaces may be difficult. The aim of this study was to analyze, in the same experimental setting, both the bactericidal activity and the effects on human keratinocytes. Exposure to b-LED induced an intense cytocidal activity against Gram-positive (i.e, Staphylococcus aureus) and Gram-negative (i.e., Pseudomonas aeruginosa) bacteria associated with catheter-related infections. Treatment with b-LED of a human keratinocyte cell line induced a transient cell cycle arrest. At the molecular level, exposure to b-LED induced a transient downregulation of Cyclin D1 and an upregulation of p21, but not signs of apoptosis. Interestingly, a transient induction of phosphor-histone γ-H2Ax, which is associated with genotoxic damages, was observed. At the same time, keratinocytes underwent a transient epithelial to mesenchymal transition (EMT)-like phenotype, characterized by E-cadherin downregulation and SNAIL/SLUG induction. As a functional readout of EMT induction, a scratch assay was performed. Surprisingly, b-LED treatment provoked a delay in the scratch closure. In conclusion, we demonstrated that b-LED microbicidal activity is associated with complex responses in keratinocytes that certainly deserve further analysis. 相似文献
666.
Serena Barozzi Valeria Bozzi Daniela De Rocco Tania Giangregorio Patrizia Noris Anna Savoia Alessandro Pecci 《International journal of molecular sciences》2021,22(19)
Bernard-Soulier syndrome (BSS) is an autosomal-recessive bleeding disorder caused by biallelic variants in the GP1BA, GP1BB, and GP9 genes encoding the subunits GPIbα, GPIbβ, and GPIX of the GPIb-IX complex. Pathogenic variants usually affect the extracellular or transmembrane domains of the receptor subunits. We investigated a family with BSS caused by the homozygous c.528_550del (p.Arg177Serfs*124) variant in GP1BB, which is the first mutation ever identified that affects the cytoplasmic domain of GPIbβ. The loss of the intracytoplasmic tail of GPIbβ results in a mild form of BSS, characterized by only a moderate reduction of the GPIb-IX complex expression and mild or absent bleeding tendency. The variant induces a decrease of the total platelet expression of GPIbβ; however, all of the mutant subunit expressed in platelets is correctly assembled into the GPIb-IX complex in the plasma membrane, indicating that the cytoplasmic domain of GPIbβ is not involved in assembly and trafficking of the GPIb-IX receptor. Finally, the c.528_550del mutation exerts a dominant effect and causes mild macrothrombocytopenia in heterozygous individuals, as also demonstrated by the investigation of a second unrelated pedigree. The study of this novel GP1BB variant provides new information on pathophysiology of BSS and the assembly mechanisms of the GPIb-IX receptor. 相似文献
667.
Domenic Prete Elisabetta Dimaggio Valeria Demontis Valentina Zannier Maria Jesus Rodriguez-Douton Lorenzo Guazzelli Fabio Beltram Lucia Sorba Giovanni Pennelli Francesco Rossella 《Advanced functional materials》2021,31(37):2104175
Semiconductor nanostructures have raised much hope for the implementation of high-performance thermoelectric generators. Indeed, they are expected to make available reduced thermal conductivity without a heavy trade-off on electrical conductivity, a key requirement to optimize the thermoelectric figure of merit. Here, a novel nanodevice architecture is presented in which ionic liquids are employed as thermally-insulating gate dielectrics. These devices allow the field-effect control of electrical transport in suspended semiconducting nanowires in which thermal conductivity can be simultaneously measured using an all-electrical setup. The resulting experimental data on electrical and thermal transport properties taken on individual nanodevices can be combined to extract ZT, guide device optimization and dynamical tuning of the thermoelectric properties. 相似文献
668.
669.
ABSTRACTWe derive bounds for the objective errors and gradient residuals when finding approximations to the solution of common regularized quadratic optimization problems within evolving Krylov spaces. These provide upper bounds on the number of iterations required to achieve a given stated accuracy. We illustrate the quality of our bounds on given test examples. 相似文献