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141.
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Vojtěch Hamala Andrea Martišová Lucie Červenková Šťastná Jindřich Karban Andrej Dančo Adam Šimarek Martin Lamač Michal Horáček Tamara Kolářová Roman Hrstka Róbert Gyepes Jiří Pinkas 《应用有机金属化学》2020,34(11):e5896
Ruthenium tetrazene complexes with general formula [Cp*RuCl(1,4-R2N4)] (Cp* = η5-C5Me5), where R = benzyl ( 1 ), 2-fluorobenzyl ( 2 ), β-d -glucopyranosyl-unprotected ( 3a ) and acyl-protected ( 3b – d ), 2-acetamido-β-d -glucopyranosyl-unprotected ( 4a ) and acyl-protected ( 4b – d ), propyl-β-d -glucopyranoside-unprotected ( 5a ), and O-acetylated ( 5b ), were synthesized and characterized using nuclear magnetic resonance and electrospray ionization–mass spectrometry. In addition, the molecular structure of 3b was determined using X-ray crystallography. The cytotoxicity of complexes against ovarian (A2780, SK-OV-3) and breast (MDA-MB-231) cancer cell lines and noncancerous cell line HEK-293 was evaluated and compared to cisplatin activity. The carbohydrate-modified complexes bearing acyl-protecting groups exhibited higher efficacy (in low micromolar range) than unprotected ones, where the most active 4d was superior to cisplatin up to five times against all investigated cancer cell lines; however, no significant selectivity was achieved. The complex induced apoptotic cell death at low micromolar concentrations (0.5 μM for A2780 and HEK293; 2 μM for SK-OV-3 and MDA-MB-231). 相似文献
144.
Petra Igličar Andrej Preželj Igor Locatelli Jurij Trontelj Samo Andrenšek Nataša Kovačić Uroš Urleb Aleš Mrhar 《Chromatographia》2009,70(7-8):1103-1112
Multiple-species plasma-stability testing and pharmacokinetic studies in rats and dogs were performed on LK-157, a novel 10-ethylidene tricyclic carbapenem and potent inactivator of β-lactamases of classes A, C, and D. An LC–MS–MS method was developed and validated for analysis of LK-157 in rat and dog plasma. Separation was achieved on a C18 column by gradient elution. The lower limit of quantification for LK-157 in plasma was 50 ng mL?1. Intra-day and inter-day precision were <12.5 and <11.8%, respectively. When degradation of LK-157 was assessed in buffer solutions and in rat, dog, and human plasma, the compound was found to be stable in pH 7.0–9.0 phosphate buffer for 24 h at room temperature, and in human plasma for 60 min at 37 °C. The stability of LK-157 was species-dependent. Results from study of in vitro metabolism showed that the enzymes liver cytochrome P450 and uridine diphosphate glycosyltransferase do not metabolize LK-157. LC–MS–MS was also successfully applied to a pharmacokinetic study. The pharmacokinetics of LK-157 after bolus intravenous administration (10 mg kg?1) to Wistar rats and Beagle dogs was described by a two-compartment pharmacokinetic model. Human pharmacokinetic data were extrapolated from dog pharmacokinetic data. The extrapolated human terminal-phase half-life of LK-157 was 2.3 h. Stability and pharmacokinetic data for LK-157 are in agreement with results for other inactivators of β-lactamases. 相似文献
145.
Ohne Zusammenfassung
Uebersetzt von Hans Erbring (Leipzig). 相似文献
146.
E. A. Dem’yanov E. V. Djukova 《Computational Mathematics and Mathematical Physics》2007,47(3):518-526
New estimates are derived for the computational complexity of the problem of constructing irredundant coverings of an integer matrix (search for maximal conjunctions of a special logical function). 相似文献
147.
Andrej T. Il’ichev 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2006,57(4):547-566
Stability of solitary waves in a thin inextensible and unshearable rod of infinite length is studied. Solitary-wave profile
of the elastica of such a rod without torsion has the form of a planar loop and its speed depends on a tension in the rod.
The linear instability of a solitary-wave profile subject to perturbations escaping from the plane of the loop is established
for a certain range of solitary-wave speeds. It is done using the properties of the Evans function, an analytic function on
the right complex half-plane, that has zeros if and only if there exist the unstable modes of the linearization around a solitary-wave
solution. The result follows from comparison of the behaviour of the Evans function in some neighbourhood of the origin with
its asymptotic at infinity. The explicit computation of the leading coefficient of the Taylor series of the Evans function
near the origin is performed by means of the symbolic computer language.
Received: April 6, 2004; revised: December 12, 2004 相似文献
148.
Lucia Kovacikova Marta Soltesova Prnova Magdalena Majekova Andrej Bohac Cimen Karasu Milan Stefek 《Molecules (Basel, Switzerland)》2021,26(10)
Aldose reductase (AR, ALR2), the first enzyme of the polyol pathway, is implicated in the pathophysiology of diabetic complications. Aldose reductase inhibitors (ARIs) thus present a promising therapeutic approach to treat a wide array of diabetic complications. Moreover, a therapeutic potential of ARIs in the treatment of chronic inflammation-related pathologies and several genetic metabolic disorders has been recently indicated. Substituted indoles are an interesting group of compounds with a plethora of biological activities. This article reviews a series of indole-based bifunctional aldose reductase inhibitors/antioxidants (ARIs/AOs) developed during recent years. Experimental results obtained in in vitro, ex vivo, and in vivo models of diabetic complications are presented. Structure–activity relationships with respect to carboxymethyl pharmacophore regioisomerization and core scaffold modification are discussed along with the criteria of ‘drug-likeness”. Novel promising structures of putative multifunctional ARIs/AOs are designed. 相似文献
149.
Ermira Begu Yaroslav Shlyapnikov Andrej Stergarsek Peter Frkal Jože Kotnik 《International journal of environmental analytical chemistry》2016,96(7):609-626
Mercury in aqueous systems can be present in different chemical forms. Of these, dissolved elemental Hg(0) (DEM) is of great importance because it can readily be partitioned between air and water. Analytical methods used for determining DEM are conventionally based on removal of Hg(0) by purging, pre-concentration on gold and detection by either cold vapour atomic absorption (CV-AAS) or atomic fluorescence spectrophotometry (CV-AFS). At present, there is no agreed protocol for the measurement of DEM in aqueous samples. A new method is described here, which is based on continuous stripping of DEM by mercury-free nitrogen in a flow injection mode and detection by CV-AAS. The partitioning of DEM between aqueous and gas phases is largely dependent on the composition of the former. Moreover, calibration using the standard addition method is not possible due to the reactivity of DEM introduced from calibration solutions. Calibration is therefore done by reference measurements using a manual method for DEM involving quantitative removal and CV-AFS detection. DEM is then determined in the water sample by applying the partitioning factor. The optimised method is precise, sensitive and linear over a wide concentration range. It has provided comparable results with the manual method when applied on board a research vessel in the Mediterranean Sea (0.02–0.05 ng L?1) and during a pilot laboratory-scale experiment on industrial aqueous media from wet flue gas desulphurisation (WFGD) equipment (2–300 ng L?1). 相似文献
150.