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71.
To help to clarify therapeutic functions of lipoic acid (LA) in biochemical and clinical practice we have elaborated a fast, simple and accurate HPLC method enabling determination of LA in human urine. The proposed analytical approach includes reduction of LA with tris(2‐carboxyethyl)phosphine and simultaneous separation and derivatization of the analyte with butylamine and o‐phthaldialdehyde followed by spectrofluorimetric detection at λex = 340 nm and λem = 440 nm. The assay was performed using gradient elution and the mobile phase containing 0.0025 mol L?1 o‐phthaldialdehyde in 0.0025 mol L?1 NaOH and acetonitrile. Linearity of the detector response for LA was observed in the range of 0.3–8 μmol L?1. Limits of detection and quantification for LA in urine samples were 0.02 and 0.03 μmol L?1, respectively. The total analysis time, including sample work‐up, was <20 min. The analytical procedure was successfully applied to analysis of real urine samples delivered from six healthy volunteers who received a single 100 mg dose of LA. 相似文献
72.
Paulina Maksym Magdalena Tarnacka Kamila Wolnica Andrzej Dzienia Andrzej Zięba Kamil Kaminski Marian Paluch 《Journal of polymer science. Part A, Polymer chemistry》2018,56(23):2681-2691
The synthesis of tailored [2-(methacryloyloxy)ethyl]-trimethylammonium chloride (ChMA/Cl−) and bis(trifluoromethanesulfonate) imide (ChMA/NTf2−)-based ionic homopolymers by sustainable activators generated by electron transfer atom transfer radical polymerization (ATRP) method has been demonstrated. Linear and four-arm star-shaped macromolecules were obtained with the use of two synthetic strategies: (a) direct polymerization of ionic monomers with counterions differing in hydrophilicity (prepolymerization) and (2) modification by ion exchange from Cl− to NTf2− (postpolymerization) using both classical ATRP initiator and pentaerythritol-based initiator. The effect of counterions on the polymerization kinetics and the physicochemical and thermodynamical properties of resulted poly(ionic liquid)s (PILs) has been investigated. Results showed that polymerizations of ChMA/NTf2− proceeded with higher rate in comparison to ChMA/Cl− one independently on the predetermined topologies (linear and four-arm star-shaped). From thermodynamical point of view, the glass transition temperature Tg increased with molecular weight Mn for linear- and star-shaped PILs for both types of counterion. In addition, star-shaped polymers of comparable Mn to linear ones were characterized by slightly higher Tg values. The resulting polyelectrolytes, after modification via exchange of Cl− anions to NTf2− ones were characterized by much higher Tg in comparison to those produced by direct polymerization of ionic monomer, indicating the crucial role of postpolymerization modification on thermodynamical properties of PILs. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2681–2691 相似文献
73.
Edgar Fuentes Kamila Boháčová Ana M. Fuentes-Caparrós Dr. Ralf Schweins Dr. Emily R. Draper Dr. Dave J. Adams Dr. Silvia Pujals Dr. Lorenzo Albertazzi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):9869-9873
Self-assembly of fluorenylmethoxycarbonyl-protected diphenylalanine (FmocFF) in water is widely known to produce hydrogels. Typically, confocal microscopy is used to visualize such hydrogels under wet conditions, that is, without freezing or drying. However, key aspects of hydrogels like fiber diameter, network morphology and mesh size are sub-diffraction limited features and cannot be visualized effectively using this approach. In this work, we show that it is possible to image FmocFF hydrogels by Points Accumulation for Imaging in Nanoscale Topography (PAINT) in native conditions and without direct gel labelling. We demonstrate that the fiber network can be visualized with improved resolution (≈50 nm) both in 2D and 3D. Quantitative information is extracted such as mesh size and fiber diameter. This method can complement the existing characterization tools for hydrogels and provide useful information supporting the design of new materials. 相似文献
74.
Kamila Kotrasova Eva Kormanikova 《Mathematical Methods in the Applied Sciences》2020,43(13):7664-7676
This paper presents the seismic response analysis of a cylindrical container made of laminated composite. The analytical homogenization is used for calculation of the material properties of unidirectional fiber-reinforced composite layer. Constitutive relations for laminate within the classical laminate theory are considered. Effective modulus of elasticity is obtained and put into a calculation of internal forces of the laminated composite cylindrical tank. The seismic analysis of liquid storage facilities has to have different approaches as the analysis of typical structures. Because of an earthquake, the hydrodynamic impulsive and convective pressures are generated in addition to hydrostatic pressure. The solved liquid-filled container made of the laminated composite was situated for the region of Slovak Republic and was analyzed in respect of Eurocode 8 recommendations. 相似文献
75.
Joanna Jaworska Michal Kawalec Malgorzata Pastusiak Katarzyna Reczynska Henryk Janeczek Kamila Lewicka Elzbieta Pamula Piotr Dobrzynski 《Journal of polymer science. Part A, Polymer chemistry》2017,55(17):2756-2769
The main objective of the presented research was to synthesise biodegradable aliphatic polycarbonates containing reactive carboxyl pendant groups and to examine the influence of the copolymer chain microstructure and composition on the process of their hydrolytic degradation and cytocompatibility. The work describes copolymerization of cyclic trimethylene carbonate derivative containing benzyl‐ester pendant group (benzyl 5‐methyl‐2‐oxo‐1,3‐dioxane‐5‐carboxylate) with trimethylene carbonate. The copolymerization was conducted with the use of zinc (II) and lanthanum (III) acetylacetonates as ring‐opening polymerization coordination initiators. Detailed NMR analysis allowed to define the microstructure of the obtained copolymers, which depended on the composition and type of used initiator. The final tapered chain microstructure of the obtained copolymers was related to huge differences in comonomers reactivity and evidenced low level of transesterification of the main copolymer backbone. Chosen copolymers, with unprotected carbonyl groups, were subjected to in vitro degradation test and cytocompatibility studies. It was found that high concentration of carboxyl groups resulted in copolymers which formed hydrogels and were very prone to hydrolytic degradation; they were also cytotoxic toward osteoblast‐like MG 63 cells. Copolymers with lower content of carboxyl groups were found less susceptible to degradation and cytocompatible with studied cells. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2756–2769 相似文献
76.
Kamila Kliś-Garlicka 《Czechoslovak Mathematical Journal》2016,66(1):119-125
The notion of a bilattice was introduced by Shulman. A bilattice is a subspace analogue for a lattice. In this work the definition of hyperreflexivity for bilattices is given and studied. We give some general results concerning this notion. To a given lattice L we can construct the bilattice \(\sum {_L} \). Similarly, having a bilattice Σ we may consider the lattice \(\mathcal{L}_\Sigma \). In this paper we study the relationship between hyperreflexivity of subspace lattices and of their associated bilattices. Some examples of hyperreflexive or not hyperreflexive bilattices are given. 相似文献
77.
Agnieszka Łupicka-Słowik Mateusz Psurski Renata Grzywa Kamila Bobrek Patrycja Smok Maciej Walczak Andrzej Gaweł Tadeusz Stefaniak Józef Oleksyszyn Marcin Sieńczyk 《Applied biochemistry and biotechnology》2018,184(4):1358-1374
Adenosine deaminase (ADA) is currently used as a diagnostic marker for tuberculous pleuritis. Although ADA has been suggested as a potential marker for several types of cancer, the importance of each of ADA isoforms as well as their levels and enzymatic activities in tumors need to be further investigated. Herein we developed avian immunoglobulin Y highly specific to human ADA via hens immunization with calf adenosine deaminase. The obtained antibodies were used for the development of a sensitive double-egg yolk immunoglobulin (IgY) sandwich ELISA assay with an ADA detection limit of 0.5 ng/ml and a linearity range of up to 10 ng/ml. Specific, affinity-purified IgYs were able to recognize human recombinant ADA and ADA present in human cancer cell lines. In addition, antigen-specific IgY antibodies were able to inhibit catalytic activity of calf ADA with an IC50 value of 47.48 nM. We showed that generated IgY antibodies may be useful for ADA detection, thus acting as a diagnostic agent in immunoenzymatic assays. 相似文献
78.
Kamila Bendová 《Archive for Mathematical Logic》2001,40(1):19-23
Even if the ordering of all natural number is (known to be) not definable from multiplication of natural numbers and ordering
of primes, there is a simple axiom system in the language such that the multiplicative structure of positive integers has a unique expansion by a linear order coinciding with the
standard order for primes and satisfying the axioms – namely the standard one.
Received: 3 December 1998 相似文献
79.
Caffeic acid phenethyl ester (CAPE) is a strong antioxidant extracted from honey bee-hive propolis. The mentioned compound, a well-known NF-κB inhibitor, has been used in traditional medicine as a potent anti-inflammatory agent. CAPE has a broad spectrum of biological properties including anti-viral, anti-bacterial, anti-cancer, immunomodulatory, and wound-healing activities. This review characterizes published data about CAPE biological properties and potential therapeutic applications, that can be used in various diseases. 相似文献
80.