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1.
Plants (Basel) ; 11(24)2022 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-36559677

RESUMEN

Phenolic compounds of 25 newly introduced strawberry cultivars were profiled using spectrophotometry, electron paramagnetic resonance (EPR) spectroscopy, and high-performance liquid chromatography-mass spectrometry. Total phenolic and anthocyanin content (TPC and TACY, respectively), as well as vitamin C, and concentrations of individual phenolic compounds in fruits were evaluated to identify the most promising cultivars according to their phenolic profile. The highest values of TPC, TACY, and vitamin C were recorded in 'Premy' (1.53 mg eq GA g-1 FW), 'Sandra' (30.60 mg eq Pg-3-g 100 g-1 FW), and 'Laetitia' (56.32 mg 100 g-1 FW), respectively. The DPPH and •OH radicals scavenging activity of fruit methanolic extracts was estimated using EPR spectroscopy. All cultivars are almost uniformly effective in the scavenging of •OH radical, while 'Tea', 'Premy', and 'Joly' were marked as highly potent cultivars (over 70%) in terms of DPPH-antiradical activity. Specific peroxidase activities were the highest in 'Garda', 'Federica', and 'Rumba' (0.11, 0.08, and 0.06 U mg-1 prot, respectively). 'Laetitia', 'Joly', 'Arianna', 'Tea', and 'Mila' cultivars were distinguished from others as the richest concerning almost all flavonoids and phenolic acids, including some other parameters of bioactivity. These cultivars could be recommended to consumers as functional fruit foods.

2.
Psychiatr Danub ; 31(Suppl 5): 750-760, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32160168

RESUMEN

INTRODUCTION: Anxiety disorders are among the most common mental disorders. Benzodiazepines belong to the group of anxiolytic sedatives and the most prescribed drugs in the world. The aim in ours study was to evaluate the differences in the exposure of the population to benzodiazepines (in period from 2014-2018) between Serbia, Slovenia and Croatia, the three countries of the Southwestern Balkans with varying degrees of socioeconomic development. STUDY DESIGN: A academic investigator initiated, pharmacoepidemiological difference-in-difference time series analysis of population exposure to benzodiazepines between the three, geographically close Balkans countries (Slovenia, Serbia, Croatia) with varying degrees of socioeconomic development has been carried out. Study was conducted as academic investigator initiated, in a retrospective manner on monthly basis international data set from January 2014 to December 2018. RESULTS: At the annual level, during the study period from January 2014 to December 2018, compared to Slovenia, Serbia and Croatia had higher DIDs, from 5 fold (Croatia) to 6 fold (Serbia), for all benzodiazepines in total. By analyzing the differences-in-difference, we have shown that influence of both time (month) and country on DIDs is significant as well as their mutual interaction (the country x month) for all benzodiazepines in total. CONCLUSION: Serbia and Croatia must implement explicit measures of reducing benzodiazepine prescription in health primary care based on evidence-based recommendations in the indications where general medicine practitioners/family doctors most commonly prescribe these medicines. Without providing a realistic supplement/alternative to benzodiazepines such as increasing the availability of psychotherapy and improving the structure of psychiatric professionals in healthcare settings, implicit measures are not recommended for reducing prescription, implementing accountability measures for prolonged prescription of benzodiazepines, and in particular for "masked" somatic diseases. All this comes to the fore by raising economic development and socioeconomic stability.


Asunto(s)
Benzodiazepinas/economía , Desarrollo Económico , Factores Socioeconómicos , Peninsula Balcánica , Croacia , Humanos , Estudios Retrospectivos , Serbia , Eslovenia
3.
J Phys Chem A ; 121(17): 3207-3212, 2017 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-28402644

RESUMEN

The differences in the mechanism of the halogenate reactions with the same oxidizing/reducing agent, such as H2O2 contribute to the better understanding of versatile halogen chemistry. The reaction between iodate, bromate, and chlorate with hydrogen peroxide in acidic medium at 60 °C is investigated by using the electron paramagnetic resonance (EPR) spin trapping technique. Essential differences in the chemistry of iodate, bromate, and chlorate in their reactions with hydrogen peroxide have been evidenced by finding different radicals as governing intermediates. The reaction between KIO3 and H2O2 is supposed to be the source of IO2• radicals. The KBrO3 and H2O2 reaction did not produce any EPR signal, whereas the KClO3-H2O2 system was found to be a source of HO• radical. Moreover, KClO3 dissolved in sulfuric acid without hydrogen peroxide produced HO• radical as well. The minimal-core models explaining the origin of obtained EPR signals are proposed. Current findings suggested the inclusion of IO2• and HOO• radicals, and ClO2• and HO• radicals in the particular kinetic models of iodate-hydrogen peroxide and chlorate-hydrogen peroxide systems, as well as possible exclusion of BrO2• radical from the kinetic scheme of the bromate-hydrogen peroxide system. Obtained results may pave the way for understanding more complex, nonlinear reactions of these halogen-containing species.

4.
J Phys Chem B ; 118(37): 10898-905, 2014 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-25152968

RESUMEN

The binding of spin-labeled fatty acids (SLFAs) to the human serum albumin (HSA) examined by electron paramagnetic resonance (EPR) spectroscopy was studied to evaluate the potential of the HSA/SLFA/EPR technique as a biomarking tool for cancer. A comparative study was performed on two spin labels with nitroxide groups attached at opposite ends of the fatty acid (FA) chain, 5-doxyl stearic (5-DS) and 16-doxyl stearic (16-DS) acid. The effects of incubation time, different [SLFA]/[HSA] molar ratios, ethanol, and temperature showed that the position of the nitroxide group produces certain differences in binding between the two SLFAs. Spectra for different [SLFA]/[HSA] molar ratios were decomposed into two spectral components, which correspond to the weakly and strongly bound SLFAs. The reduction of SLFA with ascorbate showed the existence of a two component process, fast and slow, confirming the decomposition results. Warfarin has no effect on the binding of the two SLFAs, whereas ibuprofen significantly decreases the binding of 5-DS and has no effect on 16-DS. Together, the results of this study indicate that both SLFAs, 5-DS and 16-DS, should be used for the study of HSA conformational changes in blood induced by various medical conditions.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón , Albúmina Sérica/química , Ácido Ascórbico/química , Óxidos N-Cíclicos/química , Óxidos N-Cíclicos/metabolismo , Etanol/química , Humanos , Ibuprofeno/química , Unión Proteica , Albúmina Sérica/metabolismo , Marcadores de Spin , Temperatura , Warfarina/química
5.
Plant Sci ; 223: 49-58, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24767115

RESUMEN

Apoplastic fluid was extracted from maize (Zea mays L.) roots using two procedures: collection from the surface of intact plant roots by filter paper strips (AF) or vacuum infiltration and/or centrifugation from excised root segments (AWF). The content of cytoplasmic marker (glucose-6-phosphate, G-6-P) and antioxidative components (enzymes, organic acids, phenolics, sugars, ROS) were compared in the extracts. The results obtained demonstrate that AF was completely free of G-6-P, as opposed to AWF where the cytoplasmic constituent was detected even at mildest centrifugation (200×g). Isoelectric focusing of POD and SOD shows the presence of cytoplasmic isoforms in AWF, and HPLC of sugars and phenolics a much more complex composition of AWF, due to cytoplasmic contamination. Organic acid composition differed in the two extracts, much higher concentrations of malic acid being registered in AF, while oxalic acid due to intracellular contamination being present only in AWF. EPR spectroscopy of DEPMPO spin trap in the extracts showed persistent generation of hydroxyl radical adduct in AF. The results obtained argue in favor of the filter strip method for the root apoplastic fluid extraction, avoiding the problems of cytoplasmic contamination and dilution and enabling concentration measurements in minute regions of the root.


Asunto(s)
Filtración/métodos , Papel , Exudados de Plantas/aislamiento & purificación , Raíces de Plantas/química , Zea mays/química , Biomasa , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia por Spin del Electrón , Glucosa-6-Fosfato/metabolismo , Focalización Isoeléctrica , Peroxidasa/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/enzimología , Pirroles/metabolismo , Superóxido Dismutasa/metabolismo
6.
J Phys Chem A ; 117(16): 3292-5, 2013 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-23577613

RESUMEN

This study investigates the formation of free radicals in the Bray-Liebhafsky (BL) oscillatory reaction. The results indicate that radicals are produced during both monotonous and oscillatory dynamics observed as the change of the electron paramagnetic signal (EPR) of the spin-probe TEMPONE. EPR spin-trapping with DEPMPO suggested that the most abundant radical produced in the BL reaction is an iodine-centered radical. The EPR spectrum of the DEPMPO/iodine-centered radical adducts has not been previously reported. This study may aid in establishing a more realistic reaction mechanism of the BL reaction and related chemical oscillators.

7.
J Phys Chem A ; 115(27): 7955-8, 2011 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-21692499

RESUMEN

The existence of free radicals in iodine-based oscillatory systems has been debated for some time. Recently, we have reported the presence of reactive oxygen species (ROS) in the iodide-peroxide system in acidic medium, which is common to all iodine--based oscillatory systems ( J. Phys. Chem. A 2011 , 115 , 2247--2249 ). In this work, the goal was to identify the ROS produced in this system using an EPR spin trap which can distinguish between hydroxyl (HO(•)) and hydroperoxyl (HOO(•)) radicals. The formation of the hydroperoxyl radical was observed and a possible explanation for the low EPR signal of hydroxyl radical was proposed.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Yodo/química , Especies Reactivas de Oxígeno/análisis , Radicales Libres/análisis , Radical Hidroxilo/análisis , Peróxidos/análisis
8.
J Phys Chem A ; 115(11): 2247-9, 2011 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-21361267

RESUMEN

The iodide-peroxide system in an acidic medium was investigated as a potential source of free radicals in iodine-based chemical oscillators. The radicals were detected by EPR spin-trapping using spin-trap 5-(tert-butoxycarbonyl)-5-methyl-1-pyrroline N-oxide (BMPO), which forms stable spin-adducts with oxygen-centered radicals. The iodide-peroxide system is introduced as an easily available laboratory source of free radicals.

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