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61.
Carbon coating on Ti3SiC2 with combined super-hydrophobic and self-lubricating properties was synthesized by chlorination at 1000 °C followed by modification of the CF3(CF2)5CH2CH2SiCl3 film. Raman spectroscopy confirmed the conversion from Ti3SiC2 to highly graphitized carbon coating. Scanning electron microscopy observation showed a highly porous microstructure of graphite flakes on the coating surface. The porous structure as well as organic film on carbon coating endowed the surface with super-hydrophobic property. Because of chemical inertia of the carbon coating and the modifier, the super-hydrophobic surface was very stable under various environments. Carbon coating was a good solid lubricant and greatly reduced friction coefficient of Ti3SiC2 sliding against Si3N4, which was important for Ti3SiC2 used as engineering material. 相似文献
62.
Jan Rybnicek Ralf Lach Monika Lapcikova Josef Steidl Zdenek Krulis Wolfgang Grellmann Miroslav Slouf 《应用聚合物科学杂志》2008,109(5):3210-3223
Binary and ternary blends of PC, ABS, and PMMA were studied. The blends were produced from original and recycled materials by melt mixing in a wide range of compositions. Instrumented Charpy impact testing, tensile testing, rheology investigations, and electron microscopy were carried out to determine the relationship between the deformation and fracture behavior, blend composition, morphology, and processing parameters. Resistance against unstable crack propagation was evaluated using the concepts of J‐integral and crack‐tip‐opening displacement (CTOD). The transition from ductile elastic‐plastic to brittle‐linear elastic fracture behavior was observed in the case of PC/ABS/PMMA blend at 10% of PMMA. Reprocessing had only a slight influence on the deformation and fracture behavior of the recycled blends. The blends produced from recycled materials proved to be competitive with the original pure materials. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
63.
Monika K. Nisiewicz Agata Kowalczyk Anna Sobiepanek Agata Jagielska Barbara Wagner Julita Nowakowska Marianna Gniadek Ireneusz P. Grudzinski Tomasz Kobiela Anna M. Nowicka 《International journal of molecular sciences》2021,22(1)
Nearly half of patients with advanced and metastatic melanomas harbor a BRAF mutation. Vemurafenib (VEM), a BRAF inhibitor, is used to treat such patients, however, responses to VEM are very short-lived due to intrinsic, adaptive and/or acquired resistance. In this context, we present the action of the B-Raf serine-threonine protein kinase inhibitor (vemurafenib) on the glycans structure and metallomics profiles in melanoma cells without (MeWo) and with (G-361) BRAF mutations. The studies were performed using α1-acid glycoprotein (AGP), a well-known acute-phase protein, and concanavalin A (Con A), which served as the model receptor. The detection of changes in the structure of glycans can be successfully carried out based on the frequency shifts and the charge transfer resistance after interaction of AGP with Con A in different VEM treatments using QCM-D and EIS measurements. These changes were also proved based on the cell ultrastructure examined by TEM and SEM. The LA-ICP-MS studies provided details on the metallomics profile in melanoma cells treated with and without VEM. The studies evidence that vemurafenib modifies the glycans structures and metallomics profile in melanoma cells harboring BRAF mutation that can be further implied in the resistance phenomenon. Therefore, our data opens a new avenue for further studies in the short-term addressing novel targets that hopefully can be used to improve the therapeutic regiment in advanced melanoma patients. The innovating potential of this study is fully credible and has a real impact on the global patient society suffering from advanced and metastatic melanomas. 相似文献
64.
Karolina Bukowska-Strakova Joanna Wodek Ewelina Pitera Magdalena Kozakowska Anna Konturek-Ciela Maciej Ciela Monika Goka Witold Nowak Aleksandra Wieczorek Katarzyna Pawiska-Wsikowska Alicja Jzkowicz Maciej Siedlar 《International journal of molecular sciences》2021,22(3)
Whilst the survival rates of childhood acute lymphoblastic leukemia (ALL) have increased remarkably over the last decades, the therapy resistance and toxicity are still the major causes of treatment failure. It was shown that overexpression of heme oxygenase-1 (HO-1) promotes proliferation and chemoresistance of cancer cells. In humans, the HO-1 gene (HMOX1) expression is modulated by two polymorphisms in the promoter region: (GT)n-length polymorphism and single-nucleotide polymorphism (SNP) A(−413)T, with short GT repeat sequences and 413-A variants linked to an increased HO-1 inducibility. We found that the short alleles are significantly more frequent in ALL patients in comparison to the control group, and that their presence may be associated with a higher risk of treatment failure, reflecting the role of HO-1 in chemoresistance. We also observed that the presence of short alleles may predispose to develop chemotherapy-induced neutropenia. In case of SNP, the 413-T variant co-segregated with short or long alleles, while 413-A almost selectively co-segregated with long alleles, hence it is not possible to determine if SNPs are actually of phenotypic significance. Our results suggest that HO-1 can be a potential target to overcome the treatment failure in ALL patients. 相似文献
65.
Aneta Kaczor Nikoletta Szemerédi Dr. Katarzyna Kucwaj-Brysz Dr. Monika Dąbrowska Dr. Małgorzata Starek Dr. Gniewomir Latacz Dr. Gabriella Spengler Prof. Jadwiga Handzlik 《ChemMedChem》2021,16(15):2386-2401
ABCB1 modulation is an interesting strategy in the search for new anticancer agents that can overcome multidrug resistance (MDR). Hence, 17 new 5-arylideneimidazolones containing an amine moiety, as potential ABCB1 inhibitors, were designed, synthesized, and investigated. The series was tested in both parental (PAR) and multidrug-resistant (MDR) ABCB1-overexpressing T-lymphoma cancer cells using cytotoxicity assays. The ABCB1-modulating activity was examined in rhodamine 123 accumulation tests, followed by Pgp-Glo™ Assay to determine the influence of the most active compounds on ATPase activity. Lipophilic properties were assessed both, in silico and experimentally (RP-TLC). Pharmacophore-based molecular modelling toward ABCB1 modulation was performed. The studies allowed the identification of anticancer agents (p-fluorobenzylidene derivatives) more potent than doxorubicin, with highly selective action on MDR T-lymphoma cells (selectivity index >40). Most of the investigated compounds showed ABCB1-modulating action; in particular, two 5-benzyloxybenzylidene derivatives displayed activity nearly as strong as that of tariquidar. 相似文献
66.
Monika Savarin Urska Kamensek Katarina Znidar Vesna Todorovic Gregor Sersa Maja Cemazar 《International journal of molecular sciences》2021,22(6)
Targeting tumor vasculature through specific endothelial cell markers represents a promising approach for cancer treatment. Here our aim was to construct an antibiotic resistance gene-free plasmid encoding shRNAs to simultaneously target two endothelial cell markers, CD105 and CD146, and to test its functionality and therapeutic potential in vitro when delivered by gene electrotransfer (GET) and combined with irradiation (IR). Functionality of the plasmid was evaluated by determining the silencing of the targeted genes using qRT-PCR. Antiproliferative and antiangiogenic effects were determined by the cytotoxicity assay tube formation assay and wound healing assay in murine endothelial cells 2H-11. The functionality of the plasmid construct was also evaluated in malignant melanoma tumor cell line B16F10. Additionally, potential activation of immune response was measured by induction of DNA sensor STING and proinflammatory cytokines by qRT-PCR in endothelial cells 2H-11. We demonstrated that the plasmid construction was successful and can efficiently silence the expression of the two targeted genes. As a consequence of silencing, reduced migration rate and angiogenic potential was confirmed in 2H-11 endothelial cells. Furthermore, induction of DNA sensor STING and proinflammatory cytokines were determined, which could add to the therapeutic effectiveness when used in vivo. To conclude, we successfully constructed a novel plasmid DNA with two shRNAs, which holds a great promise for further in vivo testing. 相似文献
67.
Jarosaw Widelski Simon Vlad Luca Adrianna Skiba Monika Macig Barbara Budzyska Laurence Marcourt Jean-Luc Wolfender Krystyna Skalicka-Wo
niak 《International journal of molecular sciences》2021,22(4)
Different types of anxiety disorders have become the number one mental health issue in developed countries. The search for new, safer and effective drug-like molecules among naturally derived substances faces two difficulties: an efficient method of isolation compounds with a high-purity and high-throughput animal model for activity assay. Thus, the aim of the present study was to isolate by liquid–liquid chromatography high-purity rare coumarins from the fruits of Seseli devenyense Simonk. and evaluate their anxiolytic effect (defined as reversed thimotaxis) using a 5-days post-fertilization (dpf) Danio rerio larvae model. Liquid–liquid chromatography enabled the isolation of one simple hydroxycoumarin (devenyol) and four pyranocoumarins (cis-khellactone, d-laserpitin, isolaserpitin and octanoyllomatin). The anxiolytic effect was defined as a decrease in the time spent in the boundaries of the living space (also described as reversed thigmotaxis). Our results show that all isolated courmarins exerted a significant influence on the anxiety behavior (anxiolytic activity) in the zebrafish larvae model. According to our knowledge, this is the first report of anxiolytic activity of pyranocoumarins and devenyol. 相似文献
68.
Redox-active films have been generated via electrochemical reduction in a solution containing palladium(II) acetate and [C60]fullerene, or derivatives of C60. The C60 derivatives include piperazine (piperazine-C60), pyrrolidine (CH3-pyr-C60), and a pyrrolidine salt, [(CH3)2-pyr-C60]+ attached to the fullerene unit. In these films, fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. The polymer yields involving the piperazine and pyrrolidine derivatives of C60 are significantly lower than the yield of the C60/Pd film. The CH3-pyr-C60/Pd and [(CH3)2-pyr-C60]+/Pd films are electrochemically active in the negative potential region due to the reduction of the fullerene moiety. Reduction of the CH3-pyr-C60/Pd film is accompanied by the transport of supporting electrolyte cations from the solution into the film. In the first reduction step of the [(CH3)2-pyr-C60]+/Pd film, both cations and anions of the supporting electrolyte are involved. The piperazine-C60/Pd film exhibits electrochemical activity at both negative and positive potentials. In the negative potential region, reduction of the fullerene cage takes place. Oxidation of the piperazine moiety is responsible for the observed current in the positive potential range. Here, the oxidation process of this polymer is significantly influenced by the presence of metallic palladium particles in the film. 相似文献
69.
Monika Zab?ocka-Malicka Bart?omiej Ciechanowski Wies?aw Gawe? 《Electrochimica acta》2010,55(9):3409-3413
CsCl-NdCl3 is the next of binary MCl-NdCl3 systems (M: alkali metal) investigated for determination of relative internal mobilities of cations (bCs, bNd) by countercurrent electromigration method (Klemm's method). The results have been presented as isotherms of internal mobilities of Cs+ and Nd3+ ions on NdCl3 equivalent fraction (yNd). It has been found that internal mobility of cesium cations is higher than neodymium ones in the entire composition range (what is typical for nonsymmetrical MCl-LnCl3 systems (M: Li, Na, K; Ln: La, Nd, Dy)) and decreases with increase of NdCl3 concentration in the melt. Generally, dependence of internal mobility of lanthanide cations in melts with alkali metal chlorides on lanthanide (i.e. its atomic number and concentration) seems strongly related to stability of chloride complex anions of lanthanides in the melt. Investigated systems may be divided into two classes. The first class includes MCl-NdCl3 systems (M: Li, Na) characterized by decrease of bNd with increase of NdCl3 concentration. The second includes KCl-LnCl3 systems (Ln: La, Nd, Dy) and presented here CsCl-NdCl3 system, and is characterized by increase of bLn with concentration of Ln3+ cation. The dependence of bNd on NdCl3 concentration at 1073 K was fitted (as for other systems) by a simple equation of the form: , where is the internal mobility of Ln3+ cations in pure molten LnCl3, a the difference between internal mobility of Ln3+ cations in pure molten LnCl3 and infinitely diluted LnCl3 in molten alkali metal chloride (extrapolated), and yLnCl3 is the equivalent fraction of LnCl3. 相似文献
70.
Aleksandra Korbut Marcin Wodarczyk Karolina Rudnicka Aleksandra Szwed Przemysaw Pociski Monika Biernat Paulina Tymowicz-Grzyb Martyna Michalska Natalia Karska Sylwia Rodziewicz-Motowido Konrad Szustakiewicz 《International journal of molecular sciences》2021,22(24)
In this research, we describe the properties of three-component composite foam scaffolds based on poly(ε-caprolactone) (PCL) as a matrix and hydroxyapatite whiskers (HAP) and L-Lysine as fillers (PCL/HAP/Lys with wt% ratio 50/48/2). The scaffolds were prepared using a thermally induced phase separation technique supported by salt leaching (TIPS-SL). All materials were precisely characterized: porosity, density, water uptake, wettability, DSC, and TGA measurements and compression tests were carried out. The microstructure of the obtained scaffolds was analyzed via SEM. It was found that the PCL/HAP/Lys scaffold has a 45% higher Young’s modulus and better wettability compared to the PCL/HAP system. At the same time, the porosity of the system was ~90%. The osteoblast hFOB 1.19 cell response was also investigated in osteogenic conditions (39 °C) and the cytokine release profile of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α was determined. Modification of PCL scaffolds with HAP and L-Lysine significantly improved the proliferation of pre-osteoblasts cultured on such materials. 相似文献