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731.
Lachezar Radev Vladimir Hristov Irena Michailova Bisserka Samuneva 《Central European Journal of Chemistry》2009,7(3):317-321
In this work we present experimental results about synthesis, structure evolution and in vitro bioactivity of new calcium phosphate silicate/wollastonite (CPS/W) glass-ceramics. The samples obtained were synthesized
via polystep sol-gel process with different Ca/P+Si molar ratio (R). The structure of the materials obtained was studied by
XRD, FTIR spectroscopy and SEM. XRD showed the presence of Ca15(PO4)2(SiO4)6, β-CaSiO3 and α-CaSiO3 for the sample with R=1.89 after thermal treatment at 1200°C/2h. The XRD results are in good agreement with FTIR analysis.
SEM denotes that apatite formation can be observed after soaking in simulated body fluid (SBF).
相似文献
732.
Jolanta Sarowska Dorota Wojnicz Agnieszka Jama-Kmiecik Magdalena Frej-Mdrzak Irena Choroszy-Krl 《Molecules (Basel, Switzerland)》2021,26(15)
Human noroviruses, which belong to the enterovirus family, are one of the most common etiological agents of food-borne diseases. In recent years, intensive research has been carried out regarding the antiviral activity of plant metabolites that could be used for the preservation of fresh food, because they are safer for consumption when compared to synthetic chemicals. Plant preparations with proven antimicrobial activity differ in their chemical compositions, which significantly affects their biological activity. Our review aimed to present the results of research related to the characteristics, applicability, and mechanisms of the action of various plant-based preparations and metabolites against norovirus. New strategies to combat intestinal viruses are necessary, not only to ensure food safety and reduce infections in humans but also to lower the direct health costs associated with them. 相似文献
733.
Kitanovski Z Grgić I Yasmeen F Claeys M Cusak A 《Rapid communications in mass spectrometry : RCM》2012,26(7):793-804
734.
Anna Krzyewska Marta Baranowska-Kuczko Anna Jastrzb Irena Kasacka Hanna Kozowska 《Molecules (Basel, Switzerland)》2022,27(10)
Cannabidiol (CBD) is a plant-derived compound with antioxidant and anti-inflammatory properties. Pulmonary hypertension (PH) is still an incurable disease. CBD has been suggested to ameliorate monocrotaline (MCT)-induced PH, including reduction in right ventricular systolic pressure (RVSP), a vasorelaxant effect on pulmonary arteries and a decrease in the white blood cell count. The aim of our study was to investigate the effect of chronic administration of CBD (10 mg/kg daily for 21 days) on the parameters of oxidative stress and inflammation in the lungs of rats with MCT-induced PH. In MCT-induced PH, we found a decrease in total antioxidant capacity (TAC) and glutathione level (GSH), an increase in inflammatory parameters, e.g., tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), nuclear factor kappa B (NF-κB), monocyte chemoattractant protein-1 (MCP-1), and cluster of differentiation 68 (CD68), and the overexpression of cannabinoid receptors type 1 and 2 (CB1-Rs, CB2-Rs). Administration of CBD increased TAC and GSH concentrations, glutathione reductase (GSR) activity, and decreased CB1-Rs expression and levels of inflammatory mediators such as TNF-α, IL -1β, NF-κB, MCP-1 and CD68. In conclusion, CBD has antioxidant and anti-inflammatory effects in MCT-induced PH. CBD may act as an adjuvant therapy for PH, but further detailed preclinical and clinical studies are recommended to confirm our promising results. 相似文献
735.
736.
Sanja B. Kokanov Nenad R. Filipović Aleksandar Višnjevac Milan Nikolić Irena Novaković Goran Janjić Berta Barta Holló Sandra Ramotowska Paulina Nowicka Mariusz Makowski Özlem Uğuz Atıf Koca Tamara R. Todorović 《应用有机金属化学》2023,37(1):e6942
Interest in Cd complexes has been growing in recent years. Cd complexes are considered a potential solution in the search for novel antibiotics that can fight antimicrobial resistance. In addition, Cd complexes draw attention to material chemistry. The main objective of this work was to prepare the first Cd(II) complexes with anionic forms of pyridine-based thiazolyl hydrazone (THs) ligands HLS2 [(E)-4-(4-methoxyphenyl)-2-(2-[pyridine-2-ylmethylene]hydrazinyl)thiazole] and HLS3 [(E)-2-(2-[pyridine-2-ylmethylene]hydrazinyl)-4-(p-tolyl)thiazole] and perform their structural and spectroscopic characterization, as well as stability in solution and upon heating. Studies related to their biological activities and possible electrochromic applications are also being conducted. Complexes [Cd(HLS2)2] ( 1 ) and [Cd(HLS3)2] ( 2 ) have been characterized by a single-crystal X-ray diffraction and computational analysis of intermolecular interactions responsible for their solid-state structures was performed. Thermal stability of 1 and 2 in the solid-state was analyzed by TGA/MS, where as their solution stability was determined by the spectrophotometric titration method. Electrochemical and in situ UV–Vis spectroelectrochemical analyses of 1 and 2 were carried out to determine redox mechanisms and the influence of the substituents and electrolytes on their redox responses. The antioxidant capacity of both complexes was tested in antioxidant assays, while their antimicrobial activity was tested against five Gram-positive and four Gram-negative bacteria, as well as against three fungi. The obtained results indicate their potent antioxidant capacity. The antimicrobial activity of investigated compounds on almost all tested bacterial strains was stronger than that of the standard antibiotic erythromycin. The results of docking studies indicate that the minor groove DNA is the possible biological target of 1 and 2 . 相似文献
737.
Dr. Irena Senkovska Dr. Volodymyr Bon Dr. Leila Abylgazina Dr. Matthias Mendt Jan Berger Dr. Gregor Kieslich Prof. Petko Petkov Jhonatan Luiz Fiorio Dr. Jan-Ole Joswig Prof. Thomas Heine Larissa Schaper Christopher Bachetzky Prof. Rochus Schmid Prof. Roland A. Fischer Prof. Andreas Pöppl Prof. Eike Brunner Prof. Dr. Stefan Kaskel 《Angewandte Chemie (International ed. in English)》2023,62(33):e202218076
Flexible porous frameworks are at the forefront of materials research. A unique feature is their ability to open and close their pores in an adaptive manner induced by chemical and physical stimuli. Such enzyme-like selective recognition offers a wide range of functions ranging from gas storage and separation to sensing, actuation, mechanical energy storage and catalysis. However, the factors affecting switchability are poorly understood. In particular, the role of building blocks, as well as secondary factors (crystal size, defects, cooperativity) and the role of host–guest interactions, profit from systematic investigations of an idealized model by advanced analytical techniques and simulations. The review describes an integrated approach targeting the deliberate design of pillared layer metal–organic frameworks as idealized model materials for the analysis of critical factors affecting framework dynamics and summarizes the resulting progress in their understanding and application. 相似文献
738.
Ciglenečki Irena Orlović-Leko Palma Vidović Kristijan Simonović Niki Marguš Marija Dautović Jelena Mateša Sarah Galić Ivo 《Journal of Solid State Electrochemistry》2023,27(7):1781-1793
Journal of Solid State Electrochemistry - This paper describes the application of a methodology, which primarily involves low-cost voltammetry, to rapidly track the reactivity (i.e. surfactant... 相似文献
739.
George Georgiev Anna Tzoneva Lyudmil Lyutov Stefko Iliev Irena Kamenova Ventseslava Georgieva Elena Kamenska Andreas Bund 《Macromolecular Symposia》2004,210(1):393-401
The precipitation temperature (Tpr) value of aqueous poly(dimethylamino-ethoxyacryloyl-propylsulphonate) (PDMAPS) solutions decreases with the rise of electric field intensity both in the absence and in the presence of a low molecular salt. This electrostimulated Tpr shift is explained qualitatively by means of the model taking into account both the dominating intermacromolecular dipole-dipole interaction and the dipole cluster formation. 相似文献