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81.
Andreea Iosageanu Daniela Ilie Oana Craciunescu Ana-Maria Seciu-Grama Anca Oancea Otilia Zarnescu Ionut Moraru Florin Oancea 《Molecules (Basel, Switzerland)》2021,26(9)
In the present study, we evaluated for the first time the photoprotective effect of fish bone bioactive peptides (FBBP) preparation isolated from silver carp (Hypophthalmichthys molitrix) discarded tissue using in vitro experimental models of skin cells exposed to ultraviolet B (UVB) irradiation and stressing agents. FBBP preparation was obtained by papain treatment of minced bones and centrifugal ultrafiltration, and the molecular weight (MW) distribution was characterized by size exclusion and reversed-phase high performance liquid chromatography (RP-HPLC). In vitro assessment of the effect of FBBP pretreatment in UVB-irradiated L929 fibroblasts and HaCaT keratinocytes revealed their cytoprotective activity. Their capacity to efficiently reduce reactive oxygen species (ROS) production and lipid peroxidation varied in a dose-dependent manner, and it was greater in fibroblasts. A decrease of proinflammatory cytokines secretion, in particular of tumor necrosis factor alpha (TNF-α), was found after FBBP pretreatment of THP-1-derived inflamed macrophages. Melanin production and tyrosinase activity investigated in UVB-irradiated Mel-Juso cells were lowered in direct relation to FBBP concentrations. FBBP fractions with high radical scavenging activity were separated by ion exchange chromatography, and two collagenic sequences were identified. All these results offer new scientific data on aquaculture fish bone-derived peptides confirming their ability to control the antioxidant, anti-inflammatory and pigmentation processes developed during UV irradiation of skin cells and recommend their use as valuable natural ingredients of photoprotective cosmeceutical products. 相似文献
82.
Aurora Reiss Nicoleta Cioater Aurelian Dobriescu Mihaela Rotaru Alice Carla Carabet Filippo Parisi Anca Gnescu Irina Dbuleanu Cezar Ionu Spînu Petre Rotaru 《Molecules (Basel, Switzerland)》2021,26(10)
New Co(II), Ni(II), and Cu(II) complexes were synthesized with the Schiff base ligand obtained by the condensation of sulfathiazole with salicylaldehyde. Their characterization was performed by elemental analysis, molar conductance, spectroscopic techniques (IR, diffuse reflectance and UV–Vis–NIR), magnetic moments, thermal analysis, and calorimetry (thermogravimetry/derivative thermogravimetry/differential scanning calorimetry), while their morphological and crystal systems were explained on the basis of powder X-ray diffraction results. The IR data indicated that the Schiff base ligand is tridentate coordinated to the metallic ion with two N atoms from azomethine group and thiazole ring and one O atom from phenolic group. The composition of the complexes was found to be of the [ML2]∙nH2O (M = Co, n = 1.5 (1); M = Ni, n = 1 (2); M = Cu, n = 4.5 (3)) type, having an octahedral geometry for the Co(II) and Ni(II) complexes and a tetragonally distorted octahedral geometry for the Cu(II) complex. The presence of lattice water molecules was confirmed by thermal analysis. XRD analysis evidenced the polycrystalline nature of the powders, with a monoclinic structure. The unit cell volume of the complexes was found to increase in the order of (2) < (1) < (3). SEM evidenced hard agglomerates with micrometric-range sizes for all the investigated samples (ligand and complexes). EDS analysis showed that the N:S and N:M atomic ratios were close to the theoretical ones (1.5 and 6.0, respectively). The geometric and electronic structures of the Schiff base ligand 4-((2-hydroxybenzylidene) amino)-N-(thiazol-2-yl) benzenesulfonamide (HL) was computationally investigated by the density functional theory (DFT) method. The predictive molecular properties of the chemical reactivity of the HL and Cu(II) complex were determined by a DFT calculation. The Schiff base and its metal complexes were tested against some bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis). The results indicated that the antibacterial activity of all metal complexes is better than that of the Schiff base. 相似文献
83.
Kulcsar M Beleaga A Silvestru C Nicolescu A Deleanu C Todasca C Silvestru A 《Dalton transactions (Cambridge, England : 2003)》2007,(21):2187-2196
Cleavage of the Se-Se bond in [2-{O(CH(2)CH(2))(2)NCH(2)}C(6)H(4)](2)Se(2) (1) and [2-{MeN(CH(2)CH(2))(2)NCH(2)}C(6)H(4)](2)Se(2) (2) by treatment with SO(2)Cl(2), bromine or iodine (1 : 1 molar ratio) yielded [2-{O(CH(2)CH(2))(2)NCH(2)}C(6)H(4)]SeX [X = Cl (3), Br (4), I (5)] and [2-{MeN(CH(2)CH(2))(2)NCH(2)}C(6)H(4)]SeI (6). The compounds were characterized in solution by NMR spectroscopy (1H, 13C, 15N, 77Se, 2D experiments). The solid-state molecular structures of 1-3, 4.HBr, 5 and 6 were established by single crystal X-ray diffraction. In all cases T-shaped coordination geometries, i.e. (C,N)SeSe (1, 2), (C,N)SeX (3, 5, 6; X = halogen) or CSeBr(2) (4.HBr), were found. Supramolecular associations in crystals based on hydrogen contacts are discussed. 相似文献
84.
We describe the Chow ring with rational coefficients of as the subring of invariants of a ring , relative to the action of the group of symmetries Sd. We compute by following a sequence of intermediate spaces for . 相似文献
85.
Imgon Hwang Seulgi So Mohamed Mokhtar Abdelmohsen Alshehri Shaeel A. Al‐Thabaiti Dr. Anca Mazare Prof. Patrik Schmuki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9204-9208
In the present work we report significant enhancement of the photoelectrochemical properties of self‐ organized TiO2 nanotubes by a combined “de‐coring” of classic nanotubes followed by an appropiate TiCl4 treatment. We show that, except for the expected particle decoration, a key effect of the TiCl4 treatment is that the electron transport characteristics in TiO2 nanotubes can be drastically improved, for example, we observe an enhancement of up to 70 % in electron‐transport times. 相似文献
86.
Elise Duhamel Alpar Pöllnitz Adina Stegarescu Prof. Dr. Anca Silvestru 《无机化学与普通化学杂志》2011,637(10):1355-1360
Redistribution reactions between diorganodiselenides of type [2‐(R2NCH2)C6H4]2Se2 [R = Et, iPr] and bis(diorganophosphinothioyl disulfanes of type [R′2P(S)S]2 (R = Ph, OiPr) resulted in the hypervalent [2‐(R2NCH2)C6H4]SeSP(S)R′2 [R = Et, R′ = Ph ( 1 ), OiPr ( 2 ); R = iPr, R′ = Ph ( 3 ), OiPr ( 4 )] species. All new compounds were characterized by solution multinuclear NMR spectroscopy (1H, 13C, 31P, 77Se) and the solid compounds 1 , 3 , and 4 also by FT‐IR spectroscopy. The crystal and molecular structures of 3 and 4 were determined by single‐crystal X‐ray diffraction. In both compounds the N(1) atom is intramolecularly coordinated to the selenium atom, resulting in T‐shaped coordination arrangements of type (C,N)SeS. The dithio organophosphorus ligands act monodentate in both complexes, which can be described as essentially monomeric species. Weak intermolecular S ··· H contacts could be considered in the crystal of 3 , thus resulting in polymeric zig‐zag chains of R and S isomers, respectively. 相似文献
87.
Luminita?AndronicEmail author Diana?Andrasi Alexandru?Enesca Maria?Visa Anca?Duta 《Journal of Sol-Gel Science and Technology》2011,58(1):201-208
A comparative study of TiO2 powders prepared by sol–gel methods is presented. Titanium tetraisopropoxide was used as the precursor for the sol–gel processes.
The effects of the annealing treatment on phase, crystallite size, porosity and photodegradation of dyes (methyl orange and
methylene blue) were studied. The phase structure, microstructure and surface properties of the films were characterized by
using X-ray diffraction (XRD) and Atomic Force Microscopy (AFM). The X-ray diffraction was used for crystal phase identification,
for the accurate estimation of the anatase–rutile ratio and for the crystallite size evaluation of each polymorph in the samples.
It was found that the only TiO2 anatase phase of the synthesized TiO2 develops below 500 °C, between 600 and 800 °C the anatase coexist with rutile and above 800 °C only the rutile phase was
found in the samples. Attention has been paid not only to crystal structures, but also to the porosity, the particle size
and the photocatalytic properties. However, the annealing temperature was found to have significant influence on the photocatalytic
properties. Different TiO2 doctor blade thin films were obtained mixing the sol gel powder (100% anatase) and TiO2 Aldrich with TiO2 Degussa P25. The surfactant (Triton X100 or sodium dodecyl sulfate) affects the packing density of the particles during deposition
and the photocatalytic degradation efficiency of the dyes. The photocatalytic degradation kinetics of methyl orange and methylene
blue using TiO2 thin film were investigated. 相似文献
88.
Charge transfer interactions in mixtures of poly(9-vinylcarbazole) with three nitro compounds (4,4′dinitrodibenzyl, ethyl
3,5-dinitrobenzoate and 2,2′,4,4′-tetranitrodibenzyl) were examined. 相似文献
89.
Thomas M Wishart David G Brownstein Derek Thomson Anca M Tabakova Katherine M Boothe Jack W Tsao Thomas H Gillingwater 《BMC neuroscience》2009,10(1):148-8
Background
The slow Wallerian Degeneration (Wld S ) gene specifically protects axonal and synaptic compartments of neurons from a wide variety of degeneration-inducing stimuli, including; traumatic injury, Parkinson's disease, demyelinating neuropathies, some forms of motor neuron disease and global cerebral ischemia. The Wld S gene encodes a novel Ube4b-Nmnat1 chimeric protein (WldS protein) that is responsible for conferring the neuroprotective phenotype. How the chimeric WldS protein confers neuroprotection remains controversial, but several studies have shown that expression in neurons in vivo and in vitro modifies key cellular pathways, including; NAD biosynthesis, ubiquitination, the mitochondrial proteome, cell cycle status and cell stress. Whether similar changes are induced in non-neuronal tissue and organs at a basal level in vivo remains to be determined. This may be of particular importance for the development and application of neuroprotective therapeutic strategies based around Wld S -mediated pathways designed for use in human patients. 相似文献90.
Adina Morozan Anca Dumitru Claudia Nastase Florin Nastase Ioan Stamatin 《Macromolecular Symposia》2008,267(1):129-133
Confidence in the potential of hydrogen as an energy vector and fuel bring the opportunities for enhancing electrolyzer performance. The aim of this paper is to develop new polymer nanocomposites as electrolyte membranes for PEM-electrolyzer. A series of nanocomposite membranes, including GEFC/TiO2, GEFC/CNTs, and GEFC/TiO2CNTs have been developed and characterized by FT-IR spectroscopy and AFM. The application of polymer nanocomposite membranes in electrochemical cells for water electrolysis was investigated. Experimental results obtained with respect to performance are reported and discussed related to GEFC membrane. 相似文献