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Petr Solich - One of the best experts on this subject based on the ideXlab platform.
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advantages of application of uplc in pharmaceutical analysis
Talanta, 2006Co-Authors: Lucie Nováková, Ludmila Matysová, Petr SolichAbstract:Ultra Performance Liquid Chromatography (UPLC) is a relatively new technique giving new possibilities in liquid chromatography, especially concerning decrease of time and solvent consumption. UPLC chromatographic system is designed in a special way to withstand high system back-pressures. Special analytical columns UPLC Acquity UPLC BEH C(18) packed with 1.7 microm particles are used in connection with this system. The quality control analyses of four pharmaceutical formulations were transferred from HPLC to UPLC system. The results are compared for Triamcinolon cream containing trimacinolone acetonide, methylparaben, Propylparaben and triamcinolone as degradation product, for Hydrocortison cream (hydrocortisone acetate, methylparaben, Propylparaben and hydrocortisone degradation product), for Indomethacin gel (indomethacin and its degradation products 4-chlorobenzoic acid and 5-methoxy-2-methylindoleacetic acid) and for Estrogel gel (estradiol, methylparaben, Propylparaben and estrone as degradation product). The UPLC system allows shortening analysis time up to nine times comparing to the conventional system using 5 microm particle packed analytical columns. In comparison with 3 microm particle packed analytical columns analysis should be shortened about three times. The negative effect of particle decrease is back-pressure increase about nine times (versus 5 microm) or three times (versus 3 microm), respectively. The separation on UPLC is performed under very high pressures (up to 100MPa is possible in UPLC system), but it has no negative influence on analytical column or other components of chromatographic system. Separation efficiency remains maintained or is even improved. Differences and SST parameters, advantages and disadvantages of UPLC are discussed.
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Simultaneous HPLC determination of ketoprofen and its degradation products in the presence of preservatives in pharmaceuticals.
Journal of pharmaceutical and biomedical analysis, 2004Co-Authors: Josef Dvorak, R. Hájková, Ludmila Matysová, Lucie Nováková, Michael A. Koupparis, Petr SolichAbstract:Abstract A novel and quick high-performance liquid chromatography (HPLC) method with UV spectrophotometric detection was developed and validated for the determination of five compounds in topical gel. The described method is suitable for simultaneous determination of active component ketoprofen, two preservatives methylparaben and Propylparaben and two degradation products of ketoprofen—3-acetylbenzophenone and 2-(3-carboxyphenyl) propionic acid—in a topical cream after long-term stability tests using ethylparaben as an internal standard. The chromatographic separation was performed on a 5 μm Supelco Discovery C18 column (125 mm × 4 mm i.d., Sigma–Aldrich); the optimal mobile phase for separation of ketoprofen, methylparaben, Propylparaben, degradation products 3-acetylbenzophenone and 2-(3-carboxyphenyl) propionic acid and ethylparaben as internal standard consists of a mixture of acetonitril, water and phosphate buffer pH 3.5 (40:58:2, v/v/v). At a flow rate of 1.0 ml min −1 and detection at 233 nm, the total time of analysis was less than 10 min. The method was applied for routine analysis (batch analysis and stability tests) of these compounds in topical pharmaceutical product.
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Determination of methylparaben, Propylparaben, triamcinolone acetonide and its degradation product in a topical cream by RP-HPLC
Analytical and bioanalytical chemistry, 2003Co-Authors: Ludmila Matysová, R. Hájková, J. Šícha, Petr SolichAbstract:A novel reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the determination of active component triamcinolone acetonide, its degradation product triamcinolone (occurring in formulation after long-term stability tests) and two preservatives presented in the cream—methylparaben and Propylparaben, using hydrocortisone as an internal standard.
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Determination of methylparaben, Propylparaben, clotrimazole and its degradation products in topical cream by RP-HPLC
Chromatographia, 2002Co-Authors: Petr Solich, R. Hájková, Marie Pospíšilová, J. ŠíchaAbstract:Reversed-phase, high-performance liquid chromatographic (RP-HPLC) methods with UV detection were developed and validated for determination of compounds in a topical cream. The first method describes determination of the active component clotrimazole and two preservatives present in the cream; methylparaben and Propylparaben. The second method describes determination of two degradation products of clotrimazole, imidazole and (2-chlorophenyl) diphenylmethanol, in a topical cream after long-term stability tests.
Ramon Bernabeu - One of the best experts on this subject based on the ideXlab platform.
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anticonvulsant effect of sodium cyclamate and Propylparaben on pentylenetetrazol induced seizures in zebrafish
Synapse, 2017Co-Authors: Antonella Piserafuster, Sofia Otero, Alan Talevi, Luis E Brunoblanch, Ramon BernabeuAbstract:: Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible, and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based on previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of pentylenetetrazole (PTZ)-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms, and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration.
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Anticonvulsant effect of sodium cyclamate and Propylparaben on pentylenetetrazol-induced seizures in zebrafish.
Synapse (New York N.Y.), 2017Co-Authors: Antonella Pisera-fuster, Luis E Bruno-blanch, Sofia Otero, Alan Talevi, Ramon BernabeuAbstract:Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based in previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of PTZ-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration. This article is protected by copyright. All rights reserved.
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anticonvulsant effect of sodium cyclamate and Propylparaben on ptz induced seizures in zebrafish
Synapse, 2017Co-Authors: Antonella Piserafuster, Sofia Otero, Alan Talevi, Luis E Brunoblanch, Ramon BernabeuAbstract:Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based in previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of PTZ-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration. This article is protected by copyright. All rights reserved.
Antonella Piserafuster - One of the best experts on this subject based on the ideXlab platform.
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anticonvulsant effect of sodium cyclamate and Propylparaben on pentylenetetrazol induced seizures in zebrafish
Synapse, 2017Co-Authors: Antonella Piserafuster, Sofia Otero, Alan Talevi, Luis E Brunoblanch, Ramon BernabeuAbstract:: Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible, and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based on previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of pentylenetetrazole (PTZ)-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms, and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration.
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anticonvulsant effect of sodium cyclamate and Propylparaben on ptz induced seizures in zebrafish
Synapse, 2017Co-Authors: Antonella Piserafuster, Sofia Otero, Alan Talevi, Luis E Brunoblanch, Ramon BernabeuAbstract:Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based in previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of PTZ-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration. This article is protected by copyright. All rights reserved.
Alan Talevi - One of the best experts on this subject based on the ideXlab platform.
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anticonvulsant effect of sodium cyclamate and Propylparaben on pentylenetetrazol induced seizures in zebrafish
Synapse, 2017Co-Authors: Antonella Piserafuster, Sofia Otero, Alan Talevi, Luis E Brunoblanch, Ramon BernabeuAbstract:: Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible, and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based on previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of pentylenetetrazole (PTZ)-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms, and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration.
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Anticonvulsant effect of sodium cyclamate and Propylparaben on pentylenetetrazol-induced seizures in zebrafish.
Synapse (New York N.Y.), 2017Co-Authors: Antonella Pisera-fuster, Luis E Bruno-blanch, Sofia Otero, Alan Talevi, Ramon BernabeuAbstract:Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based in previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of PTZ-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration. This article is protected by copyright. All rights reserved.
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anticonvulsant effect of sodium cyclamate and Propylparaben on ptz induced seizures in zebrafish
Synapse, 2017Co-Authors: Antonella Piserafuster, Sofia Otero, Alan Talevi, Luis E Brunoblanch, Ramon BernabeuAbstract:Screening for novel anticonvulsant drugs requires appropriate animal seizure models. Zebrafish provide small, accessible and cost-efficient preclinical models applicable to high-throughput small molecule screening. Based in previous results in rodents, we have here examined the effects of artificial sweetener sodium cyclamate and antimicrobial agent sodium Propylparaben on a model of PTZ-induced seizures in zebrafish. Sodium cyclamate reduced the bursts of hyperactivity, the spasms, increased the latency to spasms and the latency to seizure, while Propylparaben increased the latency to spasms. The results show the potential of zebrafish to detect novel anticonvulsant compounds while they also demonstrate the ability of two commonly ingested chemical compounds to modify the seizure threshold when were administrated at low concentration. This article is protected by copyright. All rights reserved.
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A successful virtual screening application: Prediction of anticonvulsant activity in MES test of widely used pharmaceutical and food preservatives methylparaben and Propylparaben
Journal of Computer-Aided Molecular Design, 2007Co-Authors: Alan Talevi, Carolina L. Bellera, Eduardo A Castro, Luis E Bruno-blanchAbstract:A discriminant function based on topological descriptors was derived from a training set composed by anticonvulsants of clinical use or in clinical phase of development and compounds with other therapeutic uses. This model was internally and externally validated and applied in the virtual screening of chemical compounds from the Merck Index 13th. Methylparaben (Nipagin), a preservative widely used in food, cosmetics and pharmaceutics, was signaled as active by the discriminant function and tested in mice in the Maximal Electroshock (MES) test (i.p. administration), according to the NIH Program for Anticonvulsant Drug Development. Based on the results of Methylparaben, Propylparaben (Nipasol), another preservative usually used in association with the former, was also tested. Both methyl and Propylparaben were found active in mice at doses of 30, 100, and 300 mg/kg. The discovery of the anticonvulsant activities in the MES test of methylparaben and Propylparaben might be useful for the development of new anticonvulsant medications, specially considering the well-known toxicological profile of these drugs.
M.j. Hazen - One of the best experts on this subject based on the ideXlab platform.
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the antioxidant butylated hydroxyanisole potentiates the toxic effects of Propylparaben in cultured mammalian cells
Food and Chemical Toxicology, 2014Co-Authors: Jose Manuel Perez Martin, Lidia Daimiel, Javier Martinezbotas, Covadonga Martin Sanchez, Ana Peropadre, Miguel A Lasuncion, Paloma Fernandez Freire, M.j. HazenAbstract:Abstract Butylated hydroxyanisole and Propylparaben are phenolic preservatives commonly used in food, pharmaceutical and personal care products. Both chemicals have been subjected to extensive toxicological studies, due to the growing concern regarding their possible impacts on environmental and human health. However, the cytotoxicity and underlying mechanisms of co-exposure to these compounds have not been explored. In this study, a set of relevant cytotoxicity endpoints including cell viability and proliferation, oxidative stress, DNA damage and gene expression changes were analyzed to assess whether the antioxidant butylated hydroxyanisole could prevent the pro-oxidant effects caused by Propylparaben in Vero cells. We demonstrated that binary mixtures of both chemicals induce greater cytotoxic effects than those reported after single exposure to each compound. Simultaneous treatment with butylated hydroxyanisole and Propylparaben caused G0/G1 cell cycle arrest as a result of enhanced generation of oxidative stress and DNA double strand breaks. DNA microarray analysis revealed that a cross-talk between transforming growth factor beta (TGFβ) and ataxia-telangiectasia mutated kinase (ATM) pathways regulates the response of Vero cells to the tested compounds in binary mixture. Our findings indicate that butylated hydroxyanisole potentiates the pro-oxidant effects of Propylparaben in cultured mammalian cells and provide useful information for their safety assessment.
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toxicological evaluation of three contaminants of emerging concern by use of the allium cepa test
Mutation Research-genetic Toxicology and Environmental Mutagenesis, 2012Co-Authors: Oscar Herrero, Ana Peropadre, J Perez M Martin, Fernandez P Freire, Carvajal L Lopez, M.j. HazenAbstract:Abstract Di(2-ethylhexyl)phthalate, triclosan and Propylparaben are contaminants of emerging concern that have been subjected to extensive toxicological studies, but for which limited information is currently available concerning adverse effects on terrestrial plant systems. The Allium cepa test, which is considered one of the most efficient approaches to assess toxic effects of environmental chemicals, was selected to evaluate the potential risks of these ubiquitous pollutants. Our data demonstrate that all three compounds studied may in some way be considered toxic, but different effects were noted depending on the chemical and the end point analysed. Results derived from the analysis of macroscopic parameters used in testing for general toxicity, revealed that while di(2-ethylhexyl)phthalate had no apparent effects, the other two chemicals inhibited A. cepa root growth in a dose-dependent manner. On the other hand, although all three compounds caused alterations in the mitotic index of root-tip cells, Propylparaben was the only one that did not show evidence of genotoxicity in assays for chromosome aberrations and micronuclei. The results of the present study clearly indicate that sensitive plant bioassays are useful and complementary tools to determine environmental impact of contaminants of emerging concern.
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Oxidative DNA damage contributes to the toxic activity of Propylparaben in mammalian cells.
Mutation research, 2010Co-Authors: Jose Manuel Perez Martin, Ana Peropadre, Paloma Fernandez Freire, Oscar Herrero, V. Labrador, M.j. HazenAbstract:Abstract Propyl p -hydroxybenzoate, commonly referred to as Propylparaben, is the most frequently used preservative to inhibit microbial growth and extend shelf life of a range of consumer products. The objective of this study was to provide further insight into the toxicological profile of this compound, because of the current discrepancy in the literature with regard to the safety of parabens. The Vero cell line, derived from the kidney of the green monkey, was selected to evaluate the adverse effects of Propylparaben by use of a set of mechanistically relevant endpoints for detecting cytotoxicity and genotoxic activities. Our results demonstrate that exposure to the compound for 24 h causes changes in cell-proliferation rates rather than in cell viability. A significant and dose-dependent decline in the percentage of mitotic cells was observed at the lowest concentration tested, mainly due to cell-cycle arrest at the G0/G1 phase. Immunodetection techniques revealed that induction of DNA double-strand breaks and oxidative damage underlies the cytostatic effect observed in treated Vero cells. Additional studies are in progress to extend these findings, which define a novel mode of action of Propylparaben in cultured mammalian cells.
