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排序方式: 共有887条查询结果,搜索用时 13 毫秒
361.
Nerilson M. Lima Gagan Preet Sara R. Marqui Thaís de O. R. S. Falcoski Geovana Navegante Christiane P. Soares Teresinha de Jesus A. S. Andrade Felipe A. La Porta Harinantenaina Liva R. Rakotondraie Marcel Jaspars Dulce H. S. Silva 《Molecules (Basel, Switzerland)》2022,27(15)
This work evaluated the metabolic profiling of Inga species with antitumor potential. In addition, we described the antigenotoxicity of polyphenols isolated from I. laurina and a proteomic approach using HepG2 cells after treatment with these metabolites. The in vitro cytotoxic activity against HepG2, HT-29 and T98G cancer cell lines was investigated. The assessment of genotoxic damage was carried out through the comet assay. The ethanolic extract from I. laurina seeds was subjected to bioassay-guided fractionation and the most active fractions were characterized. One bioactive fraction with high cytotoxicity against HT-29 human colon cancer cells (IC50 = 4.0 µg mL−1) was found, and it was characterized as a mixture of p-hydroxybenzoic acid and 4-vinyl-phenol. The I. edulis fruit peel (IC50 = 18.6 µg mL−1) and I. laurina seed (IC50 = 15.2 µg mL−1) extracts had cytotoxic activity against the cell line T98G, and its chemical composition showed a variety of phenolic acids. The chemical composition of this species indicated a wide variety of aromatic acids, flavonoids, tannins, and carotenoids. The high concentration (ranging from 5% to 30%) of these polyphenols in the bioactive extract may be responsible for the antitumor potential. Regarding the proteomic approach, we detected proteins directly related to the elimination of ROS, DNA repair, expression of tumor proteins, and apoptosis. 相似文献
362.
Paula M. Lima Felipe A. dos Santos Marcelo O.A. da Silva Marco A.Z. Arruda Gustavo R. de Castro 《Talanta》2010,82(3):1052-1056
An investigation was made into calcium, iron and zinc in protein spots in samples of Nile tilapia (Oreochromis niloticus) liver tissue obtained after protein separation by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and subsequent qualitative and quantitative evaluation by synchrotron radiation X-ray fluorescence (SRXRF) and Flame Atomic Absorption Spectrometry (FAAS). An analysis of the fluorescence spectra indicated the presence of calcium, iron and zinc in 12, 6 and 8 liver protein spots, respectively. The metal ions found were distributed mainly in proteins with a molar mass of less than 40.00 kDa and more than 12.00 kDa, with pI in the range of 4.70-9.40. The only exception was a spot presenting protein with a molar mass of 10.10 kDa. In addition to calcium, iron and zinc, sulfur and phosphorus - which are non-metals that may be part of the protein structure, were also detected. After microwave-assisted acid mineralization of the proteins spots, a FAAS estimation of the concentration of calcium, iron and zinc ions bound to these proteins indicated a range of 1.08-5.80 mg g−1, 2.02-8.03 mg g−1 and 1.60-8.55 mg g−1, respectively. 相似文献
363.
Clovis Peppe Melina De Azevedo Mello Felipe Terra Martins Jaqueline Pinto Vargas Felipe Christoff Wouters Robert Alan Burrow 《Journal of Coordination Chemistry》2018,71(6):813-827
AbstractBromomethyl-dibromo-indium(III), Br2InCH2Br, obtained from indium monobromide and methylene dibromide, reacts with hard and soft donor ligands to afford the corresponding indium(III) organometallic complexes. In this work, we investigated the conditions to prepare adducts of Br2InCH2Br using bis(diphenylphosphino)alkane dioxides acting as hard ligands. We report here the synthesis and crystal structures of two 1-D coordination polymers with the hard donor ligands Ph2P(O)(CH2)mP(O)Ph2 (m = 2, dppeO2 and m = 6, dpphO2). Compounds 1 and 2 with formulas [Br2In(CH2Br)(dppeO2)]n (1) and [Br2In(CH2Br)(dpphO2)]n (2) were characterized by IR and Raman spectroscopy and elemental analysis. We also obtained an ionic indium(III) compound with dppeO2 acting as a chelating ligand with formula [InBr2(dppeO2)2][InBr3(CH2Br)] (3). The crystal structures were determined for 1–3 using single crystal X-ray diffractometry. The geometry around the In(III) can be described as a trigonal bipyramid in 1 and 2, and the chains were packed onto the plane giving layers that are stabilized mainly by intermolecular interactions. Compound 3 has a square bipyramidal In(III) cation with formula [Br2L2In]+ and tetrahedral organoindium(III) anion with formula [Br3InCH2Br]–. Hirshfeld surface analysis employing 2-D fingerprint plots have been used to analyze intramolecular and intermolecular interactions present in the solid state of the structures. 相似文献
364.
A Spectroscopic Study of Colchicine in the Solid State and in Solution by Multinuclear Magnetic Resonance and Vibrational Circular Dichroism 下载免费PDF全文
Albert Virgili Ma Mar Quesada‐Moreno Juan Ramón Avilés‐Moreno Juan Jesús López‐González M. Ángeles García Rosa M. Claramunt M. Rosario Torres M. Luisa Jimeno Felipe Reviriego Ibon Alkorta José Elguero 《Helvetica chimica acta》2014,97(4):471-490
Although almost 200‐years‐old, several unknown aspects remain to be explored of colchicine, the unique available drug for acute flares of gout. In this article, we report density‐functional theory (DFT) studies of geometry, energy, and NMR; 1H‐, 13C‐, and 15N‐NMR chemical shifts and some spin‐spin coupling constants, including the complete analysis of the saturated part (ring B); the assignment of both enantiomers by NMR using a chiral solvating agent; solid‐state NMR experiments of the different forms of natural and racemic colchicine, and IR and vibrational circular dichroism (VCD) studies of these same forms. 相似文献
365.
366.
Using the Lagrangian–Grassmannian, a smooth algebraic variety of dimension n(n + 1)/2 that parametrizes isotropic subspaces of dimension n in a symplectic vector space of dimension 2n, we construct a new class of linear codes generated by this variety, the Lagrangian–Grassmannian codes. We explicitly compute
their word length, give a formula for their dimension and an upper bound for the minimum distance in terms of the dimension
of the Lagrangian–Grassmannian variety. 相似文献
367.
Transplantation of spermatogonial stem cells (SSCs), the male germline stem cells, in experimental animal models has been successfully used to study mechanisms involved in SSC self-renewal and to restore fertility. However, there are still many challenges associated with understanding the recipient immune response for SSCs use in clinical therapies. Here, we have undertaken a detailed structural study of macrophages elicited by SSCs transplantation in mice using both high-resolution light microscopy (HRLM) and transmission electron microscopy (TEM). We demonstrate that SSCs transplantation elicits a rapid and potent recruitment of macrophages into the seminiferous epithelium (SE). Infiltrating macrophages were derived from differentiation of peritubular monocyte-like cells into typical activated macrophages, which actively migrate through the SE, accumulate in the tubule lumen, and direct phagocytosis of differentiating germ cells and spermatozoa. Quantitative TEM analyses revealed increased formation of lipid bodies (LBs), organelles recognized as intracellular platforms for synthesis of inflammatory mediators and key markers of macrophage activation, within both infiltrating macrophages and Sertoli cells. LBs significantly increased in number and size in parallel to the augmented macrophage migration during different times post-transplantation. Our findings suggest that LBs may be involved with immunomodulatory mechanisms regulating the seminiferous tubule niche after SSC transplantation. 相似文献
368.
Ednei Gilberto Primel Márcio Raimundo Milani Adriana Demoliner Luis Felipe Hax Niencheski Ana Laura Venquiaruti Escarrone 《International journal of environmental analytical chemistry》2013,93(14-15):1048-1062
A preliminary study of the pollution in surface and drinking waters caused by herbicides and metals in the Municipal Water Supply System (CORSAN) in Rio Grande city, RS, Brazil, is reported. The occurrence of 5 herbicides and 9 metals was studied in surface and drinking water through the analysis of 2 sampling spots at CORSAN. The analytical determination was performed by solid-phase extraction (SPE), high performance liquid chromatography-photodiode array detection (HPLC-DAD) and liquid chromatography coupled to electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS) for herbicides, and graphite furnace atomic absorption spectrometry (GFAAS) for metals. The concentrations of herbicides in the surface water were very low; however, the herbicide clomazone was detected in more than 50% of the samples analysed in concentration exceeding 1.0?µg L?1. The concentration of metals was below the Maximum Contaminant Level (MCL) set by the Brazilian regulation. 相似文献
369.
Pedro Isaza Felipe Linares Gustavo Ponce 《Communications in Mathematical Physics》2013,324(1):129-146
We prove special decay properties of solutions to the initial value problem associated to the k-generalized Korteweg-de Vries equation. These are related with persistence properties of the solution flow in weighted Sobolev spaces and with sharp unique continuation properties of solutions to this equation. As an application of our method we also obtain results concerning the decay behavior of perturbations of the traveling wave solutions as well as results for solutions corresponding to special data. 相似文献
370.
V.?Schw?mmle E. M.F.?Curado F. D.?Nobre 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,70(1):107-116
Consequences of the connection between nonlinear Fokker-Planck equations
and entropic forms are investigated. A particular emphasis is given to
the feature that different nonlinear Fokker-Planck equations can be
arranged into classes associated with the same entropic form and its
corresponding stationary state.
Through numerical integration, the time evolution of the solution
of nonlinear Fokker-Planck equations related to the Boltzmann-Gibbs
and Tsallis entropies are analyzed.
The time behavior in both stages, in a time much smaller than the
one required for reaching the stationary state, as well as
towards the relaxation to the stationary state, are of particular interest.
In the former case, by
using the concept of classes of nonlinear Fokker-Planck equations,
a rich variety of physical behavior may be found, with some curious
situations, like an anomalous diffusion within the
class related to the Boltzmann-Gibbs entropy, as well as a
normal diffusion within the class of equations related
to Tsallis’ entropy. In addition to that, the relaxation
towards the stationary state may present a behavior
different from most of the systems studied in the literature. 相似文献