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The aim of the present study was to investigate the biological activities of Tunisian olive leaf extracts and to correlate these activities to their phytochemical composition. The phenolic profile of four Tunisian autochthonous cultivars Chemlali, Sayali, Neb jmel, and Meski was determined using LC/MS-MS. The antioxidant activity of olive leaf extracts was evaluated using DPPH test. The antiproliferative effect was also investigated using MTT assay. The phytochemical screening showed that phenolic content and phenolic class repartition were significantly affected by olive leaf cultivars. Twenty-one components were identified and oleurpein, luteolin 4-glucoside, luteolin 7-glucoside, and apigenin 7-glucoside were the major phenolic components. Among all extracts, Sayali exhibited the strongest antioxidant and antiproliferative activities (IC50 41.36 µg ml−1 / EC50 147.11 µg ml−1). The MTT result showed that olive leaf extract reduced MCF-7 cell viability in a dose-dependent manner. Western blot analysis demonstrated that olive leaf extracts exhibited antiproliferative activity through apoptosis induction.

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The effect of cadmium on protein expression in the aerial parts of barley (Hordeum vulgare L. cv. ‘Mandolina’) seedlings was investigated by proteomic analysis of leaf apoplast proteins. Dramatic changes were observed in the protein pattern of intercellular washing fluid from Cd-treated (0–300 μM) barley leaves both by 1D- and 2D-PAGE. By mass spectrometric (MALDI-TOF and/or LC-MS/MS) analysis of induced proteins PR1 proteins, certain 1-3-glucanases (PR2), chitinases (PR3), members of the chitin binding PR4 family, a rich set of thaumatin-like proteins (PR5) and two PR17 proteins were identified, indicating that a general plant defence response, inducing massive secretion of pathogenesis-related proteins (PR) into the extracellular space, is an important part of the Cd-induced stress reactions. Although systemic induction of PR proteins is probably important for an adequate plant response to cadmium stress, many of these proteins are known to have an allergenic potential and as such present a health risk to plant eaters, even when the heavy metal concentration in the given plant organ is low.

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This paper is focused on the determination of three hexabromocyclododecane isomers, α, β, and γ, in the tissue of the most commonly consumed marine and farmed fish in Central Europe. The analytical procedure contains multiple steps: extraction, dialysis using semipermeable membranes, and a clean-up step using a silica gel column. Hexabromocyclododecane (HBCD) isomers were determined by sensitive isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method which is characterized by a low limit of detection (1 pg g−1 fresh weight). The recovery values obtained for individual isomers were in the range of 89–124%. The γ-HBCD isomer was detected in all samples. This isomer also had the largest percentage in comparison with the other isomers, except in salmon, in which the α-HBCD isomer was more abundant. The highest level of total HBCD was measured in mackerel (650 ± 195 pg g−1 fresh weight). Cluster analysis allowed the differentiation of groups of objects and the display of objects based on the degree of integration within the same group. Spearman’s rank correlation indicated no statistically significant difference between the levels of HBCD and the fat content in the fish samples.

Open access
Acta Chromatographica
Authors:
S. Hiriyanna Hiriyanna
,
K. Basavaiah
,
P. S. Goud Goud
,
V. Dhayanithi
,
K. Raju
, and
H. Pati Pati

Summary

Studies of the degradation of olanzapine bulk drug under hydrolytic (acidic and alkaline), oxidising, and photolytic conditions are reported in this paper. Olanzapine is almost completely stable under photolytic and hydrolytic (acidic and alkaline) conditions. The major degradation products formed when olanzapine bulk drug was exposed to oxidative stress conditions were isolated by preparative reversed-phase high-performance liquid chromatography and characterized by FTIR, LC-MS-MS, and 1H, 13C, and DEPT NMR. On the basis of results from spectroscopy the degradation products were characterized as 10-hydroxy-2-methyl-5,10-dihydro-4H-benzo[b]thieno [2,3-e][1,4]diazepin-4-one, 2-methyl-5,10-dihydro-4H-benzo[b]thieno[2,3-e][1,4]diazepin-4-one, and 2-methyl-10-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4] diazepin-4-yloxy)-5,10-dihydro-4H-benzo[b]thieno[2,3-e]diazepin-4-one. Identification, isolation, and characterization of these oxidative degradation products are discussed in detail.

Open access

Summary

A sensitive and selective liquid chromatographic tandem mass spectrometric (LC-MS-MS) method for analysis of lovastatin in human plasma has been developed and validated. Ethyl acetate extraction was used for plasma sample preparation and simvastatin was used as internal standard. Chromatographic separation was achieved on a C18 column by isocratic elution with 83:17:0.1 (v/v) methanol-2 μM aqueous sodium acetate-formic acid as mobile phase, delivered at 1.0 mL min−1. MS-MS detection was performed using positive electrospray ionization and multiple-reaction monitoring with argon for collision-induced dissociation. Calibration plots were generated over the concentration range 0.05 to 20 ng mL−1 (r > 0.999) with a lower limit of quantification (LLOQ) of 0.05 ng mL−1. Intra and inter-day precision and accuracy were determined at four different concentrations, 0.05, 0.5, 2.0, and 10.0 ng mL−1, and precision ranged from 0.4 to 11.4% with the deviation always less than 15% (n = 5). Extraction recoveries were from 86.8 to 94.1% for lovastatin and approximately 88.0% for simvastatin. The validated method was successfully applied to a bioequivalence study of two lovastatin tablets in 20 healthy volunteers.

Open access
Journal of Psychedelic Studies
Authors:
Giordano Novak Rossi
,
Eduardo José Crevelin
,
Gabriela de Oliveira Silveira
,
Maria Eugênia Costa Queiroz
,
Mauricio Yonamine
,
Jaime Eduardo Cecilio Hallak
, and
Rafael Guimarães Dos Santos

order of concentration and identified correctly as follows. Fig. 1. Analysis spectra for each solvent utilized. Chromatograms obtained after serial dilution procedure and LC-MS/MS analysis of M. hostilis extracts performed with different organic

Open access

The effect of free-range versus cage management system on corticosterone transfer into the eggs was studied in laying hens. Hungarian Yellow laying hens (age: 21 weeks, body weight: 2.0 ± 0.5 kg) were divided into two groups in the spring: Group I, free-range keeping (n = 15 layers, density: ≯ 0.5 bird/m2) in outdoor runs, with continuous access to a commercial layer feed; Group II, hens kept in battery cages (n = 17 layers, density: 2 birds/m2, natural light, continuous access to feed and water). Eggs were collected after a one-week adaptation period on days 2, 7 and 16. Corticosterone (CST) was extracted from homogenised egg samples using an ASE-200 Accelerated Solvent Extractor and then assayed by liquid chromatography linked with tandem mass spectrometry (LC-MS/MS) [Thermo Quest Surveyor high-performance liquid chromatography (HPLC) interfaced via Atmospheric Pressure Chemical Ionisation (APCI) ion source to Finnigan/Thermo Quest LCQ Deca MS/MS] using dexamethasone as internal standard with positive APCI ionisation. CST concentrations of whole eggs laid by free-range hens on days 2, 7 and 16 were 0.370 ± 0.218, 0.259 ± 0.066 and 0.915 ± 0.745 ng·g-1, respectively, while those of eggs laid by caged hens were 0.206 ± 0.157, 0.223 ± 0.165 and 0.184 ± 0.110 ng·g-1 at the above sampling times. It is concluded that in free-range laying hens the sharp changes of environmental weather conditions significantly increased the corticosterone content of eggs, while the environmentally controlled and closed battery cage management technology resulted in relatively uniform corticosterone concentrations in the whole eggs.

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Summary

Coccidiostats are a group of drugs used for the treatment of coccidiosis. This disease is common among animals for slaughter. Residues of the mentioned drugs can be potentially harmful for human health, so there is a constant need for cheap and quick method for their determination. A novel sample preparation technique, solvent front position extraction (SFPE), for liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for such a purpose. In the SFPE procedure, the adsorbent layer of a chromatographic plate is used for purification and separation of substances of interest from matrix components. After applying the SFPE technique, solutes and the internal standard are not only separated from unwanted components, but also focused and evenly distributed in the zone located at the solvent front position. From such a zone, the substances can be directly transferred from thin-layer chromatography (TLC) plate to LC-MS instrument using the TLC-MS Interface. Focusing the substances of interest in a narrow zone improves the sensitivity of an assay, while the homogeneity of these zones guarantees their accurate quantification, even if only a part of the substance zone undergoes extraction using a TLC-MS Interface. The SFPE procedure is especially recommended for samples with high viscosity or/and with large amounts of contaminants and enables cleaning a final sample solution from matrix components, showing lower and stronger retention than the solutes of interest. In this work, the application of SFPE procedure for separation of the substances of interest from two biological matrices (bovine serum and animal feed) is presented. The results are promising and allow their application for further research of these compounds.

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Aegle marmelos Correa (Bael tree) is a medicinal fruit tree, widely used for healing purposes in various systems of medicines. Coumarins and alkaloids present in various parts of bael tree including roots and fruit pulp are the primary active constituents implicated for its biological activities. An efficient liquid chromatography–electrospray ionization—tandem mass spectrometry (LC—ESI—MS/MS) method was developed for identification and simultaneous determination of four coumarin derivatives, namely, umbelliferone, psoralene, marmin, and imperatorin, and an alkaloid, skimmianine, in root and stem bark of A. marmelos. The chromatographic separation of analytes was performed on Altima C18 (50 × 4.6 mm, 3 μm) column using methanol and 0.1% acetic acid in water (54:46, v/v) as the mobile phase under isocratic conditions. The LC–MS/MS parameters were optimized in the positive ionization mode using electrospray ionization source. The quantification of the analytes was performed using multiple reaction monitoring (MRM) transitions, umbelliferone (m/z 163.1 → 107.1), psoralene (m/z 187.2 → 131.1), marmin (m/z 333.5 → 163.2), imperatorin (m/z 271.1 → 203.1), and skimmianine (m/z 260.1 → 227.0). The extraction method was standardized for optimum yield of coumarin derivatives and the alkaloid in different extraction solvents. Higher yield of the analytes was found in methanolic extracts in comparisons to petroleum ether, chloroform, ethyl acetate, ethanol, and water. The method was validated for linear range, intra- and inter-batch precision and accuracy. The distribution of coumarin derivatives and an alkaloid was found to vary significantly in different plant samples, and their concentration was much higher in roots as compared to stem bark.

Open access

Béta-laktám antibiotikumok terápiás gyógyszerszint-monitorozása kritikus állapotú felnőtt betegekben: egycentrumos, prospektív, obszervációs pilotvizsgálat

Therapeutic drug monitoring of beta-lactam antibiotics in critically ill adult patients.

A single-center prospective observational pilot study
Orvosi Hetilap
Authors:
Lőrinc Závorszky
,
Andrea Rádler
,
Júlia Galgóczi
,
Bence Tóth
,
Ákos Csomós
,
Attila Erőss
,
Róbert Farkas
,
Gellért Karvaly
,
Lili Holub
,
Bálint Gergely Szabó
, and
Botond Lakatos

Bevezetés: A béta-laktám antibiotikumok a leggyakrabban alkalmazott antibiotikumok közé tartoznak. Effektivitásuk időfüggő, adagolásuk így akkor optimális, ha az antibiotikum plazmakoncentrációja az idő 100%-ában meghaladja a baktérium minimális gátló koncentrációját (100%fT>MIC). Az Európai Klinikai Mikrobiológiai és Infektológiai Társaság (European Society of Clinical Microbiology and Infectious Diseases – ESCMID) ezt a célértéket javasolja a béta-laktámok terápiás gyógyszerszint-monitorozása esetén. Számos vizsgálat alapján azonban úgy tűnik, hogy kritikus állapotú betegek esetében a béta-laktámok plazmakoncentrációja szuboptimális. Célkitűzés: Kutatásunk célja volt egy hazai súlyponti kórház intenzív osztályán legnagyobb gyakorisággal alkalmazott béta-laktám antibiotikumok szérumkoncentrációinak meghatározása és a terápiás céltartomány elérésének vizsgálata pilotjelleggel a kritikus állapotú betegek körében. Módszer: Prospektív, obszervációs egycentrumos vizsgálatunkba intenzív osztályon fekvő, meropenem, piperacillin/tazobaktám vagy ceftriaxon antibiotikummal kezelt betegeket vontunk be. A gyógyszerek völgykoncentrációját mértük szérumban, nagy hatékonyságú folyadékkromatográfiás (HPLC) módszerrel és folyadékkromatográffal kapcsolt tandem tömegspektrométerrel (LC–MS/MS) a 100%fT>MIC farmakodinámiás cél elérésének megítéléséhez. A célkoncentrációt kórokozótól függően az Európai Antimikrobiális Érzékenységi Bizottság (European Committee on Antimicrobial Susceptibility Testing – EUCAST) definíciói alapján határoztuk meg. Elsődleges végpontként a terápiás szérumkoncentrációt el nem érő betegek arányát vizsgáltuk. Eredmények: Vizsgálatunkban 28 beteg esetében összesen 60 antibiotikumszint-mérés történt. A betegek medián életkora 64,5 ± 28,7 év volt, 80,0%-uk (n = 22) férfi; 35,7%-uk (n = 10) belgyógyászati, 53,5%-uk (n = 15) sebészeti/traumatológiai okkal, míg 10,7%-uk (n = 3) égési sérülés miatt került intenzív osztályra. A betegek 39,3%-ánál (n = 11) volt detektálható a terápiás célt el nem érő antibiotikum-szérumkoncentráció. A meropenemkezelésben részesülő betegek közül 6 (66,6%), a piperacillin esetében 5 (41,6%), míg a ceftriaxon esetében 1 (12,5%) betegnél volt szubterápiás a mért koncentráció. Megbeszélés: Kutatásunk alapján a béta-laktám antibiotikumokkal kezelt, kritikus állapotú felnőtt betegek releváns része nem érte el a kívánt farmakodinámiás célt, különösen a piperacillin és a meropenem esetében. Következtetés: Pilotvizsgálatunk kisszámú hazai mintán reprodukálja a nemzetközi eredményeket, és megerősíti a terápiás gyógyszerszint-monitorozás szükségességét a béta-laktám-terápiában részesülő kritikus állapotú betegek körében. Orv Hetil. 2023; 164(48): 1904–1911.

Open access