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131.
Agustin A. Navarro del Cañizo Marcela Mazza Rodolfo Bellinzoni Osvaldo Cascone 《Applied biochemistry and biotechnology》1997,61(3):399-409
Foot and mouth disease virus, (FMDV) from a crude cell lysate was purified in a single step by affinity chromatography with
heparin as a ligand. The virus eluted from an Heparin-Ultrogel A4R column at 1M sodium chloride in 10 mM sodium phosphate buffer, pH 7.0, while most cell protein and albumin did so at lower
concentrations of sodium chloride in the same buffer. Purity of the eluted fraction containing the virus was assessed by SDS-PAGE,
HPLC, ultracentrifugation, and UV absorption spectrum. With this method, intact viral particles are recovered in high yield
(over 90%) and specific virus purity increases nearly 1000-fold. The capacity of the Chromatographic matrix for the virus
was found to be 1.1 mg viral mass per mL of hydrated gel. 相似文献
132.
Lavinia L. Ruta Ileana C. Farcasanu Mihaela Bacalum Mina Rileanu Arpad Mihai Rostas Constantin Daniliuc Mariana Carmen Chifiriuc Luminia Mruescu Marcela Popa Mihaela Badea Emilia Elena Iorgulescu Rodica Olar 《Molecules (Basel, Switzerland)》2021,26(22)
Novel complexes of type [Cu(N-N)(dmtp)2(OH2)](ClO4)2·dmtp ((1) N-N: 2,2′-bipyridine; (2) L: 1,10-phenantroline and dmtp: 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine) were designed in order to obtain biologically active compounds. Complexes were characterized as mononuclear species that crystallized in the space group P-1 of the triclinic system with a square pyramidal geometry around the copper (II). In addition to the antiproliferative effect on murine melanoma B16 cells, complex (1) exhibited low toxicity on normal BJ cells and did not affect membrane integrity. Complex (2) proved to be a more potent antimicrobial in comparison with (1), but both compounds were more active in comparison with dmtp—both against planktonic cells and biofilms. A stronger antimicrobial and antibiofilm effect was noticed against the Gram-positive strains, including methicillin-resistant Staphylococcus aureus (MRSA). Both electron paramagnetic resonance (EPR) and Saccharomyces cerevisiae studies indicated that the complexes were scavengers rather than reactive oxygen species promoters. Their DNA intercalating capacity was evidenced by modifications in both absorption and fluorescence spectra. Furthermore, both complexes exhibited nuclease-like activity, which increased in the presence of hydrogen peroxide. 相似文献
133.
Alberto Rojas-Ochoa Emilio J. Crdova Adela Carrillo-García Marcela Lizano Jos Pedraza-Chaverri Nelly Patio Alfredo Cruz-Gregorio Norma Osnaya 《Molecules (Basel, Switzerland)》2021,26(23)
Medulloblastoma is a common malignant brain tumor in the pediatric age. The current therapeutics present serious collateral effects. Polyphenols α-mangostin and nordihydroguaiaretic acid (NDGA) exert potent antitumoral activity in different cancer models, although their antitumoral effects have not been described in medulloblastoma cells yet. This study aimed to examine the proapoptotic effects of these polyphenols on human medulloblastoma cells. Medulloblastoma cell line Daoy was incubated with increasing concentrations of α-mangostin or NDGA for 24 h. The cell viability was analyzed using crystal violet and trypan blue dyes. Determination of the glutathione (GSH)/glutathione disulfide (GSSG) ratio and levels of carbonylated proteins was performed to evaluate the oxidative stress. Cell cycle progression and induction of cell death by fluorochrome-couple and TUNEL assays were evaluated using flow cytometry assays. Individual treatments with α-mangostin or NDGA decreased the viability of Daoy cells in a dose-dependent manner, inducing G2/M and S-G2/M cell cycle arrest, respectively. Both polyphenols induced cell death and increased oxidative stress. Very interestingly, α-mangostin showed more potent effects than NDGA. Our results indicate that α-mangostin and NDGA exert important cytostatic and cytotoxic effects in the Daoy cell line. These data highlight the potential usefulness of these compounds as an alternative strategy in medulloblastoma treatment. 相似文献
134.
Jefferson Romryo Duarte da Luz Eder A. Barbosa Thayse Evellyn Silva do Nascimento Adriana Augusto de Rezende Marcela Abbott Galvo Ururahy Adriana da Silva Brito Gabriel Araujo-Silva Jorge A. Lpez Maria das Graas Almeida 《Molecules (Basel, Switzerland)》2022,27(3)
The anti-inflammatory properties of Turnera subulata have been evaluated as an alternative drug approach to treating several inflammatory processes. Accordingly, in this study, aqueous and hydroalcoholic extracts of T. subulata flowers and leaves were analyzed regarding their phytocomposition by ultrafast liquid chromatography coupled to mass spectrometry, and their anti-inflammatory properties were assessed by an in vitro inflammation model, using LPS-stimulated RAW-264.7 macrophages. The phytochemical profile indicated vitexin-2-O-rhamnoside as an important constituent in both extracts, while methoxyisoflavones, some bulky amino acids (e.g., tryptophan, tyrosine, phenylalanine), pheophorbides, and octadecatrienoic, stearidonic, and ferulic acids were detected in hydroalcoholic extracts. The extracts displayed the ability to modulate the in vitro inflammatory response by altering the secretion of proinflammatory (TNF-α, IL-1β, and IL-6) and anti-inflammatory (IL-10) cytokines and inhibiting the PGE-2 and NO production. Overall, for the first time, putative compounds from T. subulata flowers and leaves were characterized, which can modulate the inflammatory process. Therefore, the data highlight this plant as an option to obtain extracts for phytotherapic formulations to treat and/or prevent chronic diseases. 相似文献
135.
Rodolfo Moreno‐Fuquen Eustaquio Vinicius Ribeiro de Castro Margarita Moreno Regina Helena De Almeida Santos Angela Marcela Montao 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):206-207
In the title co‐crystal, C7H5NO4·C5H4N2O3, the two components are linked by an intermolecular hydrogen bond between the O—H and N—O groups [O?O 2.577 (3) Å]. The interplanar angle between the planes of the rings of the molecules is 5.3 (2)°. The rings are stacked in the crystal with a mean interplanar distance of 3.279 (3) Å. 相似文献
136.
Marcela Morvová 《Czechoslovak Journal of Physics》1999,49(12):1703-1719
The plasmochemical and/or electrocatalytical reactions of carbon monoxide with water vapour were studied. Dc corona discharge
of both polarities at room temperature and temperatures enhanced up to 70°C was applied at pressures close to atmospheric.
The reaction products were analysed by IR absorption spectrometry. The main products in the gas phase were CO2 and CH4. The reactions are influenced by the formation of a catalytically active surface layer on electrodes. The composition of
this layer depends on the polarity of electrode. 相似文献
137.
Jan Chalupa Karel Handlíř Zdeňka Padělková Marcela Vejsová Vladimír Buchta Robert Jirásko Aleš Rûžička 《应用有机金属化学》2008,22(6):308-313
The set of four triorganotin(IV) diesters of 4‐ketopimelic acid containing {2‐[(CH3)2NCH2]C6H4}‐ as a C,N‐chelating ligand was prepared. Their structures were studied by the help of IR, NMR and X‐ray crystallographic techniques in the case of {{2‐[(CH3)2NCH2]C6H4}SnPh2}2[(OOCCH2CH2)2C?]. All these compounds are monomeric both in solid state and solution with five‐coordinated tin atoms and medium strong intramolecular Sn? N connection. The antimycotical activity of these compound was studied and compared with the triorganotin(IV) derivatives of 4‐ketopimelic acid and antimycotical drugs in clinical use. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
138.
139.
The nuclear spin conversion of a molecule is the modification of the total nuclear spin I of its equivalent atoms. This phenomenon is observed by measuring the relaxation rate of a gas sample initially prepared with a population of spin isomers far from the equilibrium given by nuclear spin statistics. New experimental data obtained at low pressure show a surface-induced enhancement of the nuclear spin conversion in 13CH3F. Contrary to binary collisions in the gas phase, hitting the surface induces direct conversion. Several mechanisms are proposed. 相似文献
140.
Mariângela B. M. De Azevedo Joel Alderete Jaime A. Rodriguez Ana O. Souza Daniel Rettori Marcio A. Torsoni Adelaide Faljoni-Alario Marcela Haun Nelson Durân 《Journal of inclusion phenomena and macrocyclic chemistry》2000,37(1-4):93-101
Violacein is a poorly water-soluble antitumoraland antibacterial drug. The solubility can be enhanced by complexation with-cyclodextrin. The inclusion complex was prepared by the co-precipitation method in molarratios of 1 : 1 and 1 : 2 of violacein/-cyclodextrin, respectively. The acutetoxicity (E. coli strain) of violacein did not changeup to 400 M, either in thepresence or absence of cyclodextrin. Cytotoxicity (V-79 cellculture) through DNA and MTT assays was significantlydecreased in the presence of the 1 : 2 molar ratio complex.Studies on erythrocyte lipid peroxidation by the thiobarbituricacid (TBA) methodshowed that violacein and violacein/-CD (1 : 2) at100 M cause 50% and 80% inhibition, respectively. At 500 M theviolacein/-CD complexinhibited lipid peroxidation completely; however, withfree violacein only 65% inhibition was reached at that concentration. 相似文献