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101.
Joanna Kwiczak-Yiitba Jean-Luc Pirat David Virieux Jean-Noël Volle Agnieszka Janiak Marcin Hoffmann Jakub Mrzygd Dariusz Wawrzyniak Jan Barciszewski Donata Pluskota-Karwatka 《RSC advances》2019,9(42):24117
Several novel phosphono-perfluorophenylalanine derivatives, as mimetics of phenylalanine, were synthesized by subjecting diethyl (2-(perfluorophenyl)-1-(phenylamino)ethyl)-phosphonate to SNAr reactions with different types of nucleophiles such as thiols, amines and phenols. The structure of the products was confirmed using spectroscopic and spectrometric techniques. For two compounds X-ray single crystal diffraction analysis and DFT investigations were performed providing information in regard to the preferable conformation, hydrogen bonds and other interactions. The antiproliferative potency of some of the new phosphono-perfluorophenylalanine derivatives obtained as well as representatives of previously synthesized perfluorophenyl phosphonate analogues of phenylalanine was studied on selected glioma cell lines. Preliminary evaluation of the compounds drug likeness was examined with respect to Lipinski''s and Veber''s rules, and showed that they meet the criteria perfectly. MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay results demonstrated that the compounds exhibit moderate activity against the glioblastoma multiforme cell lines (T98G and U-118 MG). Moreover most of the studied SNAr reaction products displayed significantly higher inhibitory activity against both cancer cell lines than the parent diethyl (2-(perfluorophenyl)-1-(phenylamino)ethyl)phosphonate.Several novel phosphono-perfluorophenylalanine derivatives, as mimetics of phenylalanine, were synthesized by subjecting diethyl (2-(perfluorophenyl)-1-(phenylamino)ethyl)-phosphonate to SNAr reactions with thiols, amines and phenols. 相似文献
102.
Wojteczek Anna Dardzińska Jolanta A. Małgorzewicz Sylwia Gruszecka Agnieszka Zdrojewski Zbigniew 《Clinical rheumatology》2020,39(1):227-232
Clinical Rheumatology - Gastrointestinal complaints of scleroderma (SS) patients are risk factors for impaired nutritional status, so insightful assessment is necessary. The aim was comparison of... 相似文献
103.
Joanna Augustynowicz Krzysztof Tokarz Agnieszka Baran Bartosz J. Płachno 《Archives of environmental contamination and toxicology》2014,66(4):572-581
The objective of the present work was to study the phytoremediation capacity of Callitriche cophocarpa concerning water contaminated with thallium (Tl), cadmium (Cd), zinc (Zn), and lead (Pb) derived from the natural environment. We found that after a 10-day incubation period, shoots of C. cophocarpa effectively biofiltrated the water so that it met (for Cd, Zn, and Pb) appropriate quality standards. The order of accumulation of the investigated elements by shoots (mg kg?1 dry weight) were as follows: Zn (1120) < Tl (251) < Cd (71) < Pb (35). The order of bioconcentration factors were as follows: Cd (1177) < Tl (1043) < Zn (718) < Pb (597). According to Microtox bioassay, C. cophocarpa significantly eradicated polluted water toxicity. During the experiment, the physiological status of plants was monitored by taking measurements of photosystem II activity (maximum efficiency of PSII, photochemical fluorescence quenching, nonphotochemical fluorescence quenching, and quantum efficiency of PSII), photosynthetic pigment contents, and shoot morphology. Plants exposed to metallic pollution did not exhibit significant changes in their physiological status compared with the control. This work is potentially applicable to the future use of C. cophocarpa in the phytoremediation of polluted, natural watercourses. 相似文献
104.
Agnieszka Wąsik Edyta Możdżeń Jerzy Michaluk Irena Romańska Lucyna Antkiewicz-Michaluk 《Neurotoxicity research》2014,25(4):323-334
Oxidative stress is a major contributing factor in a range of brain pathologies and in the etiology of depression. 1-Methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) is an endogenous substance which is present in the mammalian brain and exhibits neuroprotective, and monoamine oxidase (MAO)-inhibiting properties. In the present study, in order to investigate the potential role of 1MeTIQ as an antidepressant, we tested antidepressant-like effects of 1MeTIQ in comparison with desipramine (a classic antidepressant) in the forced swimming test (FST), and using HPLC methodology, we measured the concentrations of monoamines (dopamine, noradrenaline, serotonin) and the rate of their metabolism. 1MeTIQ given alone as well as in combination with desipramine produced an antidepressant-like effect and decreased the immobility time in the FST. Neurochemical data have shown that 1MeTIQ like desipramine, activated the noradrenergic system. However, the mechanism of action of 1MeTIQ is broader than the actions of desipramine, and 1MeTIQ inhibits the MAO-dependent oxidation of dopamine and serotonin in all investigated structures. We can conclude that 1MeTIQ exhibits antidepressant-like activity in the FST in the rat. The mechanism of its antidepressant action differs from desipramine and seems to be mostly associated with the inhibition of the catabolism of monoamines and their increased concentrations in the brain. 1MeTIQ seems to be very beneficial from the clinical point of view as a reversible MAO inhibitor with a significant antidepressant effects. 相似文献
105.
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107.
El?bieta Senkus Jolanta Szade Beata Pieczyńska Anna ?aczek Joanna Pikiel Katarzyna Sosińska-Mielcarek Agnieszka Karpińska Jacek Jassem 《International journal of clinical and experimental pathology》2014,7(1):353-363
The biology and pathomechanism of bilateral breast cancers is not fully understood. We compared the morphological and immunohistochemical characteristics of primary tumors in patients with synchronous bilateral breast cancers and metachronous bilateral breast cancers, with special focus on intrinsic tumor phenotype. Methods: Tumor morphology and expression of 8 immunohistochemical markers were assessed in tissue microarrays containing primary breast tumor cores from 113 metachronous bilateral breast cancers and 61 synchronous bilateral breast cancers. Analyzed markers included hormone receptors (estrogen receptor, progesterone receptor), HER2, Ki67, cytokeratin 5/6, E-cadherin, vimentin and epidermal growth factor receptor. Cutoff levels are provided in the table. Results: Metachronous bilateral breast cancers tumors had lower estrogen receptor expression (p=0.047) and higher expression of cytokeratin 5/6 (p=0.017) and of vimentin (p=0.008); in multivariate analysis only vimentin retained the significance (p=0.01). Ten (13%) and 11 (26%) of metachronous bilateral breast cancers and synchronous bilateral breast cancers had luminal A phenotype, 39 (50%) and 15 (36%) were luminal B HER2-negative, 13 (17%) and 12 (28%) - luminal B HER2-positive, 3 (4%) and 2 (5%) - HER2-positive (not luminal), and 12 (16%) and 2 (5%) had triple negative phenotype (p=0.07). Conclusion: Metachronous bilateral breast cancers, compared to synchronous bilateral breast cancers, are characterized by more aggressive phenotype, expressed by lower expression of estrogen receptor and stronger expression of cytokeratin 5/6 and vimentin; this does not, however, translate into differences in the distribution of intrinsic tumor phenotypes. 相似文献
108.
109.
Currently, carriers of active ingredients in the form of particles of a size measured in nanometers are the focus of interest of research centers worldwide. So far, submicrometer emulsions, liposomes, as well as microspheres, and nanospheres made of biodegradable polymers have been used in medicine. Recent studies show particular interest in nanoparticles based on lipids, and at the present time, are even referred to as the “era of lipid carriers”. With the passage of time, lipid nanoparticles of the so-called first and second generation, SLN (Solid Lipid Nanoparticles) and nanostructured lipid carriers and NLC (Nanostructured Lipid Carriers), respectively, turned out to be an alternative for all imperfections of earlier carriers. These carriers are characterized by a number of beneficial functional properties, including, among others, structure based on lipids well tolerated by the human body, high stability, and ability to carry hydro- and lipophilic compounds. Additionally, these carriers can enhance the distribution of the drug in the target organ and alter the pharmacokinetic properties of the drug carriers to enhance the medical effect and minimize adverse side effects. This work is focused on the current review of the state-of-the-art related to the synthesis and applications of popular nanoparticles in medicine, with a focus on their use, e.g., in COVID-19 vaccines. 相似文献
110.
A series of 2-phenacylbenzoxazole difluoroboranes named BODIPY dyes (1–8) was designed and applied as photosensitizers (PS) for radical photopolymerization of acrylate monomer. The light absorption within the ultraviolet-visible (UV–Vis) range (λmax = 350–410 nm; εmax = 23,000–42,500 M−1cm−1), that is strongly influenced by the substituents on the C3 and C4 atoms of phenyl ring, matched the emission of the Omnicure S2000 light within 320–500 nm. The photosensitizer possess fluorescence quantum yield from about 0.005 to 0.99. The 2-phenacylbenzoxazole difluoroboranes, together with borate salt (Bor), iodonium salt (Iod) or pyridinium salt (Pyr) acting as co-initiators, can generate active radicals upon the irradiation with a High Pressure Mercury Lamp which initiates a high-performance UV–Vis light-induced radical polymerization at 320–500 nm. The polymers obtained are characterized by strong photoluminescence. It was found that the type of radical generator (co-initiator) has a significant effect on the kinetic of radical polymerization of acrylate monomer. Moreover, the chemical structure of the BODIPY dyes does not influence the photoinitiating ability of the photoinitiator. The concentration of the photoinitiating system affects the photoinitiating performance. These 2-phenacylbenzoxazole difluoroborane-based photoinitiating systems have promising applications in UV–Vis-light induced polymerization. 相似文献