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Sample records for agent combining hplc

  1. Quality control of PET labeled agents by TLC, GC and HPLC

    International Nuclear Information System (INIS)

    Radioactive nuclides emitting β+-radiation are used for labeling in PET diagnostic. Before the radioactive labeled agent can be used, the radiochemical purity has to be determined by means of two separate radio-chromatography methods. For HPLC, TLC, GC and CE special radioactivity detectors sensitive for β+-radiation are required, which fulfil the regulations of various international and national authorities. All conventional chromatography detectors in applications of HPLC, TLC, GC and CE like UV-absorption, fluorescence, reflective index, conductivity, amperometry etc. have an analog signal output 0-1 V. Therefore all signal recording and peak integration systems for chromatography have analog inputs of 0-1 V. (author)

  2. RAPID RP-HPLC METHOD FOR SIMULTANEOUS SEPARATION AND ESTIMATION OF METOPROLOL AND AMLODIPINE IN COMBINATION TABLET FORMULATION

    OpenAIRE

    JastiVasavi; Murukutla Vijaya Lakshmi; Nekkalapu Satya Sundari

    2013-01-01

    The aim of the present work was to develop a RP-HPLC method for simultaneous separation of Metoprolol and Amlodipine and validate the developed method for quantitative determination of the above said drugs in combination tablet dosage form. A simple, rapid, validated chromatographic method was developed for separation and determination of metoprolol and amlodipine in tablet preparations. The anti-hypertensive agents were separated using Welchrom RP-C18 Column (4.6 mm X 250 mm, 5 µ), Shimadzu ...

  3. Combined effects, ionizing radiation plus other agents

    International Nuclear Information System (INIS)

    It is clear from cell studies, and confirmed in a general way by animal sudies, that radiation produces effects that are interactive with those due to other physical agents, chemicals of various types, and viruses. Our understanding is limited, however, in respect to the mechanisms of action in cells and, accordingly, even less penetrating in respect to our comprehension of effects in animals. Thus, the conclusion follows at this time, that we are unable to predict responses in humans due to combined action because of our incomplete understanding of individual and combined responses of radiation and other agents in experimental systems. The study of possible public health hazards due to the combined effects of radiation plus other agents is one that should be coverged upon simultaneously by the laboratory investigator and the epidemiologist-public health specialist. What is clear is the likelihood that agents biologically active in their own right may interact. Indeed, an important and significant guiding principle can be extracted from current knowledge. Relative to induced cellular changes, agents that register lesions in the genetic substance of a cell are likely to produce interactive effects. Such effects may become expressed in individual cells, in tissues, or in whole organisms

  4. Rational Combinations of Targeted Agents in AML

    Directory of Open Access Journals (Sweden)

    Prithviraj Bose

    2015-04-01

    Full Text Available Despite modest improvements in survival over the last several decades, the treatment of AML continues to present a formidable challenge. Most patients are elderly, and these individuals, as well as those with secondary, therapy-related, or relapsed/refractory AML, are particularly difficult to treat, owing to both aggressive disease biology and the high toxicity of current chemotherapeutic regimens. It has become increasingly apparent in recent years that coordinated interruption of cooperative survival signaling pathways in malignant cells is necessary for optimal therapeutic results. The modest efficacy of monotherapy with both cytotoxic and targeted agents in AML testifies to this. As the complex biology of AML continues to be elucidated, many “synthetic lethal” strategies involving rational combinations of targeted agents have been developed. Unfortunately, relatively few of these have been tested clinically, although there is growing interest in this area. In this article, the preclinical and, where available, clinical data on some of the most promising rational combinations of targeted agents in AML are summarized. While new molecules should continue to be combined with conventional genotoxic drugs of proven efficacy, there is perhaps a need to rethink traditional philosophies of clinical trial development and regulatory approval with a focus on mechanism-based, synergistic strategies.

  5. On-line identification of the bioactive compounds from Blumea gariepina by HPLC-UV-MS and HPLC-UV-NMR, combined with HPLC-micro-fractionation.

    Science.gov (United States)

    Queiroz, E F; Ioset, J R; Ndjoko, K; Guntern, A; Foggin, C M; Hostettmann, K

    2005-01-01

    The dichloromethane extract of the aerial parts of Blumea gariepina (Asteraceae) was shown to be active against the phytopathogenic fungus Cladosporium cucumerinum and to inhibit acetylcholinesterase. In order rapidly to identify the active principles, the crude extract was analysed by on-flow HPLC-1H-NMR. HPLC-micro-fractionation was performed and all peaks collected were submitted to assays against C. cucumerinum and acetylcholinesterase. By this means, the biological activities could be efficiently associated with selected HPLC peaks. Complementary on-line structural data for all peaks of interest in the crude extract were obtained from HPLC-MS and from HPLC-UV with post-column addition of UV shift reagents. This chemical screening strategy with integrated bioassays permitted the on-line identification of a number of constituents and gave useful information for an efficient isolation procedure. PMID:15997849

  6. Computerized cyclic voltammetric detection after HPLC of the antineoplastic agents etoposide, teniposide, adriamycin and its metabolite adriamycinol in urine samples

    OpenAIRE

    Ploegmakers, H. H. J. L.; Moritz, P. A.; Toll, P. J. M. M.; Oort, W.J. van

    1989-01-01

    A computerized electrochemical detection system for application after HPLC, provided with a cyclic voltammetric oxidative and reductive module, is described for the on-line qualitative determination of electroactive antineoplastic agents and metabolites in urine samples, collected from cancer patients, following intravenous administration. The application of two cyclic voltammetric detection modes provides an insight into both oxidative and reductive electrode reactions of compounds, passing ...

  7. Analysis of Bovine Serum Albumin Ligands from Puerariae flos Using Ultrafiltration Combined with HPLC-MS

    OpenAIRE

    Ping Tang; Shihui Si; Liangliang Liu

    2015-01-01

    Rapid screening techniques for identification of active compounds from natural products are important not only for clarification of the therapeutic material basis, but also for supplying suitable chemical markers for quality control. In the present study, ultrafiltration combined with high performance liquid chromatography-mass spectrometry (HPLC-MS) was developed and conducted to screen and identify bovine serum albumin (BSA) bound ligands from Puerariae flos. Fundamental parameters affectin...

  8. Development and application of a HPLC method for eight sunscreen agents in suncare products.

    Science.gov (United States)

    Peruchi, L M; Rath, S

    2012-06-01

    This work describes the development, validation and application of a simple and fast high-performance liquid chromatography-with diode array dectection (HPLC-DAD) method for the determination of eight sunscreen agents: benzophenone-3, octocrylene, ethylhexyl methoxycinnamate, ethylhexyl salicylate, homosalate (used in two isomeric forms), butyl methoxydibenzoylmethane, 4-methylbenzylidene camphor and ethylhexyl dimethyl PABA in sunscreen formulations. The separation of the eight sunscreen compounds was achieved using an ACE C18 column (250 × 4.6 mm, 5 μm), with a column temperature 20°C, and a mobile phase of 88 : 12 (v/v) methanol-water with isocratic elution. Column temperature strongly influences the retention time and resolution of the compounds. The flow rate was 1.0 mL min(-1) and quantitation was performed by external calibration at the maximum wavelength of each compound. The sample preparation was simple and consisted basically of sample dilution with methanol, centrifugation and filtration in syringe filters before quantitation. Total run time was 18 min. The method was validated according to the parameters: linear range, linearity, selectivity, intra-day and inter-day precision and accuracy. Ten samples of sunscreen emulsions commercially available in Brazil (SPF 30) from different manufacturers were analysed using the proposed method. The number of the sunscreen agents varied between one and five in a single sample. The concentrations of all compounds were in the range of 0.9-10% (w/w) and were in accordance with the current Brazilian legislation. PMID:22214440

  9. RAPID RP-HPLC METHOD FOR SIMULTANEOUS SEPARATION AND ESTIMATION OF METOPROLOL AND AMLODIPINE IN COMBINATION TABLET FORMULATION

    Directory of Open Access Journals (Sweden)

    JastiVasavi

    2013-09-01

    Full Text Available The aim of the present work was to develop a RP-HPLC method for simultaneous separation of Metoprolol and Amlodipine and validate the developed method for quantitative determination of the above said drugs in combination tablet dosage form. A simple, rapid, validated chromatographic method was developed for separation and determination of metoprolol and amlodipine in tablet preparations. The anti-hypertensive agents were separated using Welchrom RP-C18 Column (4.6 mm X 250 mm, 5 µ, Shimadzu LC-20 AT Prominence Liquid Chromatograph and the mobile phase constituted of 10 mM Phosphate buffer (pH 3.0: acetonitrile (50:50, v/v. The flow rate was 1.0 mL/min and the analyses were performed using Shimadzu SPD-20A Prominence UV-Visible detector at 235 nm. The separation of the anti-hypertensive agents, Metoprolol and Amlodipine was achieved within 5 minutes. Metoprolol and Amlodipine eluted at retention times of 2.690 minutes and 3.797 minutes respectively. The drugs obeyed Beer’s law in the concentration range of 5 - 25 µg/mL for metoprolol and 1 - 5 µg/mL for amlodipine. The developed assay method was found to be selective, precise and accurate. The method has been successfully applied for determination of Metoprolol and Amlodipine in pharmaceutical combination tablet dosage form. This developed method is sensitive, fast, and simple with excellent peak symmetry and high resolution.

  10. Quantitative lipopolysaccharide analysis using HPLC/MS/MS and its combination with the limulus amebocyte lysate assay[S

    OpenAIRE

    Pais De Barros, Jean-Paul; Gautier, Thomas; Sali, Wahib; Adrie, Christophe; Choubley, Hélène; Charron, Emilie; Lalande, Caroline; Le Guern, Naig; Deckert, Valérie; Monchi, Mehran; Quenot, Jean-Pierre; Lagrost, Laurent

    2015-01-01

    Quantitation of plasma lipopolysaccharides (LPSs) might be used to document Gram-negative bacterial infection. In the present work, LPS-derived 3-hydroxymyristate was extracted from plasma samples with an organic solvent, separated by reversed phase HPLC, and quantitated by MS/MS. This mass assay was combined with the limulus amebocyte lysate (LAL) bioassay to monitor neutralization of LPS activity in biological samples. The described HPLC/MS/MS method is a reliable, practical, accurate, and ...

  11. Quantal health effects of three toxic agents combined

    International Nuclear Information System (INIS)

    Quantal health effects such as cancer, correlated with the combined action of three toxic agents, are considered. Data on the combined effects of two agents are scarce and no such data exist for three toxicants, yet concerns have arisen about simultaneous exposure of radiation workers to three different agents. Using models developed from the analysis of health effects involving two toxicants, equations for the combined effects of three agents are derived from a more general formalism. An application of practical interest is the incidence of cancer of the esophagus and its correlation with concurrent exposures to alcohol, tobacco, and either low- or high-LET radiation. (author)

  12. HPLC-DAD-ELSD Combined Pharmacodynamics and Serum Medicinal Chemistry for Quality Assessment of Huangqi Granule.

    Directory of Open Access Journals (Sweden)

    Huaguo Chen

    Full Text Available To more scientifically and reasonably control the quality of Huangqi Granules, preliminary studies on the pharmacodynamics and serum pharmacochemistry of this medicine were performed. DPPH and MTT experiments showed that water extracts of Huangqi Granules had good antioxidant activity and increased immunity. Timed blood samples collected 5 min, 15 min, and 30 min after oral administration of a set amount of Huangqi Granules were collected and tested using UPLC-ESI-MS/MS. As a result, calycosin-7-O-β-D-glucoside, ononin, calycosin, astragaloside IV, and formononetin were found to exist in rat blood after dosing, indicating that the five chemical compounds might have pharmacological activity, and based on this result, they were designated biomarkers for quality control of Huangqi Granules. Consequently, a simple, rapid and efficient method was developed in the present study for the simultaneous determination of the five characteristic compounds in Huangqi Granules using HPLC-DAD-ELSD.The separation was performed using an Agilent Hypersil ODS column (4.6 × 250 mm, 5 μm at 30 ℃. The mobile phase was composed of water (solvent A and acetonitrile (solvent B with a flow rate of 1 mL/min. The drift tube temperature of the ELSD system was set to 85 ℃, and the nitrogen pressure was 3.5 bar.All five characteristic compounds had good linear behavior with r2 values greater than 0.9972. The recoveries varied from 96.31% to 101.22%. Subsequently, the developed method was applied to evaluate the quality of Huangqi Granules from different batches, and hierarchical clustering analysis (HCA was used to analyze the classification of the samples based on the values of the five compounds.The established HPLC method combined with HCA proved to be effective to evaluate the quality of Huangqi Granules.

  13. Quantal health effects for a combination of several toxic agents

    International Nuclear Information System (INIS)

    Quantal health effects caused by the combined action of a number of toxic agents are modeled using the information available for each toxicant acting in isolation. Two basic models are used; one assumes no interaction, the other postulates a separable kind of interaction in which each agent contributes an enhancement factor independent of all other agents. These two models provide yardsticks by which to measure synergisms and antagonisms in the interaction between the effects of toxic agents. Equations are given in approximations for small and large values of the risk. (author)

  14. Qualitative and Quantitative Evaluation of Epimedium and Ginseng Contained Combinations Using HPLC

    Institute of Scientific and Technical Information of China (English)

    MAYuan-chun; LUOMai; SarahWittenberg; CliveBarwell; ZHOUYu-xin; WEILu-xue

    2003-01-01

    Aim:To develop a rapid,effective method for the detemination of flavonoids and ginsenosides in one injection and evaluate the flavonoids and ginsenosides content to control the ratio of Epimedium and Ginseng herbs in botanical combinations.Methods: The quality evaluation was determinatted using reversed-phase high performance liquid chromatog raphy(HPLC),referred by the major flovonoids from Epimedium,epimedin A,epimedin B,epimedin C,and icariin as the standards,and the major ginsenosides Rg1,Re,Rf,Rb1,Rb2,and Rd as the standards,included Epimedium brevicornum Maxim.,E.sagittatum(Sieb.et Zucc)Maxim.,E.koreanum NaKai,P.ginseng C.A.Meyer,P.quinquefolium L.,P.notoginseng and some products containing the above herbs.Results:The main flavonoids and ginsenosides could be clearly resolved in the single analysis.Conclusion.The results can be effectively used in evaluating qualitatively and quantitatively the ration of Epimdium and Ginseng contained products.

  15. Strategies to Optimize Molecularly Targeted Anti-Cancer Agent Combinations

    Directory of Open Access Journals (Sweden)

    Ayse Erdogan

    2015-12-01

    Full Text Available Cytotoxic agents which are used in cancer chemotherapy reduced several times the number of neoplastic cells but not fully. Therefore, usage of and ldquo;targeted therapeutics" which were developed with much more rational approach is increasing markedly in patients with solid cancer. Targeted therapeutics due to selective targets aims cancer cells with specific molecular defect thereby, kils the cancer cells, which makes it possible to continue normal cells in a healthy environment. The rapid emergence of hundreds of new agents that modulates ever-growing list of the cancer-specific molecular targets promise great hope for cancer patients. Evaluation of the target agent individually, in combination with standard therapy and other target agents bring about important development challenges. As possible combinations of drugs number is unlimited, the identification of the most promising combinations and giving priority to assessing their strategies are very important.In this article important elements of the development strategy of the target agent combinations will be considered. Difficulties in this kind of combinations of rational pre-clinical and clinical evaluation and possible approaches to overcome these challenges will be discussed. [Archives Medical Review Journal 2015; 24(4.000: 432-451

  16. Combined HPLC-CUPRAC (cupric ion reducing antioxidant capacity) assay of parsley, celery leaves, and nettle.

    Science.gov (United States)

    Yildiz, Leyla; Başkan, Kevser Sözgen; Tütem, Esma; Apak, Reşat

    2008-10-19

    This study aims to identify the essential antioxidant compounds present in parsley (Petroselinum sativum) and celery (Apium graveolens) leaves belonging to the Umbelliferae (Apiaceae) family, and in stinging nettle (Urtica dioica) belonging to Urticaceae family, to measure the total antioxidant capacity (TAC) of these compounds with CUPRAC (cupric ion reducing antioxidant capacity) and ABTS spectrophotometric methods, and to correlate the TAC with high performance liquid chromatography (HPLC) findings. The CUPRAC spectrophotometric method of TAC assay using copper(II)-neocuproine (2,9-dimethyl-1,10-phenanthroline) as the chromogenic oxidant was developed in our laboratories. The individual antioxidant constituents of plant extracts were identified and quantified by HPLC on a C18 column using a modified mobile phase of gradient elution comprised of MeOH-0.2% o-phosphoric acid and UV detection for polyphenols at 280 nm. The TAC values of HPLC-quantified antioxidant constituents were found, and compared for the first time with those found by CUPRAC. The TAC of HPLC-quantified compounds accounted for a relatively high percentage of the observed CUPRAC capacities of plant extracts, namely 81% of nettle, 60-77% of parsley (in different hydrolyzates of extract and solid sample), and 41-57% of celery leaves (in different hydrolyzates). The CUPRAC total capacities of the 70% MeOH extracts of studied plants (in the units of mmol trolox g(-1)plant) were in the order: celery leaves>nettle>parsley. The TAC calculated with the aid of HPLC-spectrophotometry did not compensate for 100% of the CUPRAC total capacities, because all flavonoid glycosides subjected to hydrolysis were either not detectable with HPLC, or not converted to the corresponding aglycons (i.e., easily detectable and quantifiable with HPLC) during the hydrolysis step. PMID:18804638

  17. Rapid screening of novel agents for combination therapy in sarcomas.

    Science.gov (United States)

    Cubitt, Christopher L; Menth, Jiliana; Dawson, Jana; Martinez, Gary V; Foroutan, Parastou; Morse, David L; Bui, Marilyn M; Letson, G Douglas; Sullivan, Daniel M; Reed, Damon R

    2013-01-01

    For patients with sarcoma, metastatic disease remains very difficult to cure, and outcomes remain less than optimal. Treatment options have not largely changed, although some promising gains have been made with single agents in specific subtypes with the use of targeted agents. Here, we developed a system to investigate synergy of combinations of targeted and cytotoxic agents in a panel of sarcoma cell lines. Agents were investigated alone and in combination with varying dose ratios. Dose-response curves were analyzed for synergy using methods derived from Chou and Talalay (1984). A promising combination, dasatinib and triciribine, was explored in a murine model using the A673 cell line, and tumors were evaluated by MRI and histology for therapy effect. We found that histone deacetylase inhibitors were synergistic with etoposide, dasatinib, and Akt inhibitors across cell lines. Sorafenib and topotecan demonstrated a mixed response. Our systematic drug screening method allowed us to screen a large number of combinations of sarcoma agents. This method can be easily modified to accommodate other cell line models, and confirmatory assays, such as animal experiments, can provide excellent preclinical data to inform clinical trials for these rare malignancies. PMID:24282374

  18. Rapid Screening of Novel Agents for Combination Therapy in Sarcomas

    Directory of Open Access Journals (Sweden)

    Christopher L. Cubitt

    2013-01-01

    Full Text Available For patients with sarcoma, metastatic disease remains very difficult to cure, and outcomes remain less than optimal. Treatment options have not largely changed, although some promising gains have been made with single agents in specific subtypes with the use of targeted agents. Here, we developed a system to investigate synergy of combinations of targeted and cytotoxic agents in a panel of sarcoma cell lines. Agents were investigated alone and in combination with varying dose ratios. Dose-response curves were analyzed for synergy using methods derived from Chou and Talalay (1984. A promising combination, dasatinib and triciribine, was explored in a murine model using the A673 cell line, and tumors were evaluated by MRI and histology for therapy effect. We found that histone deacetylase inhibitors were synergistic with etoposide, dasatinib, and Akt inhibitors across cell lines. Sorafenib and topotecan demonstrated a mixed response. Our systematic drug screening method allowed us to screen a large number of combinations of sarcoma agents. This method can be easily modified to accommodate other cell line models, and confirmatory assays, such as animal experiments, can provide excellent preclinical data to inform clinical trials for these rare malignancies.

  19. Combined Reversed Phase HPLC, Mass Spectrometry, and NMR Spectroscopy for a Fast Separation and Efficient Identification of Phosphatidylcholines

    OpenAIRE

    Jan Willmann; Herbert Thiele; Dieter Leibfritz

    2011-01-01

    In respect of the manifold involvement of lipids in biochemical processes, the analysis of intact and underivatised lipids of body fluids as well as cell and tissue extracts is still a challenging task, if detailed molecular information is required. Therefore, the advantage of combined use of high-pressure liquid chromatography (HPLC), mass spectrometry (MS), and nuclear magnetic resonance (NMR) spectroscopy will be shown analyzing three different types of extracts of the ubiquitous membrane ...

  20. Screening for anti-inflammatory components from Corydalis bungeana Turcz. based on macrophage binding combined with HPLC

    OpenAIRE

    Dong, Zi-Bo; Zhang, Yong-Hong; Zhao, Bing-Jie; Li, Chao; Tian, Gang; Niu, Ben; Qi, Hong; Feng, Liang; Shao, Jian-Guo

    2015-01-01

    Background Corydalis bungeana Turcz. (CB; family: Corydalis DC.) is an anti-inflammatory medicinal herb used widely in traditional Chinese medicine (TCM) for upper respiratory tract infection, etc., but its anti-inflammatory active molecules are unknown. This study was designed to screen for the anti-inflammatory components from CB based on macrophage binding combined with HPLC. Methods Xylene-induced ear edema in mouse and carrageenan-induced hind-paw edema in rats were used to evaluate the ...

  1. Discrimination of Polish unifloral honeys using overall PTR-MS and HPLC fingerprints combined with chemometrics

    NARCIS (Netherlands)

    Kus, P.M.; Ruth, van S.M.

    2015-01-01

    A total of 62 honey samples of six floral origins (rapeseed, lime, heather, cornflower, buckwheat and black locust) were analysed by means of proton transfer reaction mass spectrometry (PTR-MS) and HPLC-DAD. The data were evaluated by principal component analysis and k-nearest neighbours classificat

  2. Rapid, potentially automatable, method extract biomarkers for HPLC/ESI/MS/MS to detect and identify BW agents

    Energy Technology Data Exchange (ETDEWEB)

    White, D.C. [Univ. of Tennessee, Knoxville, TN (United States). Center for Environmental Biotechnology]|[Oak Ridge National Lab., TN (United States). Environmental Science Div.; Burkhalter, R.S.; Smith, C. [Univ. of Tennessee, Knoxville, TN (United States). Center for Environmental Biotechnology; Whitaker, K.W. [Microbial Insights, Inc., Rockford, TN (United States)

    1997-12-31

    The program proposes to concentrate on the rapid recovery of signature biomarkers based on automated high-pressure, high-temperature solvent extraction (ASE) and/or supercritical fluid extraction (SFE) to produce lipids, nucleic acids and proteins sequentially concentrated and purified in minutes with yields especially from microeukaryotes, Gram-positive bacteria and spores. Lipids are extracted in higher proportions greater than classical one-phase, room temperature solvent extraction without major changes in lipid composition. High performance liquid chromatography (HPLC) with or without derivatization, electrospray ionization (ESI) and highly specific detection by mass spectrometry (MS) particularly with (MS){sup n} provides the detection, identification and because the signature lipid biomarkers are both phenotypic as well as genotypic biomarkers, insights into potential infectivity of BW agents. Feasibility has been demonstrated with detection, identification, and determination of infectious potential of Cryptosporidium parvum at the sensitivity of a single oocyst (which is unculturable in vitro) and accurate identification and prediction, pathogenicity, and drug-resistance of Mycobacteria spp.

  3. Effect of the combination of different depigmenting agents in vitro.

    Science.gov (United States)

    Martínez-Gutiérrez, Alfredo; Asensio, Juan Antonio; Aran, Begoña

    2014-01-01

    Melanin plays a key role in our skin, protecting us against ultraviolet radiation, but there are situations in which its anomalous accumulation can lead to either aesthetic problems or diseases like melasma. For this reason, it is important to find agents that are able to decrease the skin pigmentation. It has been demonstrated that the melanin synthesis pathway can be inhibited at different levels by different mechanisms of action. The aim of this project is to combine some of these agents with different mechanisms of action on this pathway in order to find synergistic effects in the inhibition of tyrosinase and melanin synthesis. Kojic acid + α-lipoic acid combination are the only ones that have shown a synergistic effect over mushroom tyrosinase. However, this effect is not seen in melanin synthesis inhibition, although this combination is the most effective one. A potentiation effect is seen in arbutin + α-lipoic acid and kojic acid + azelaic acid combination. Kojic acid and α-lipoic acid combination might prove a good approach as treatment for hyperpigmentation disorders. PMID:25898763

  4. Combination of HPLC and 252-Cf plasma desorption mass spectrometry for identifying composition of ginseng tinctures.

    Science.gov (United States)

    Elkin, Y N; Makhankov, V V; Uvarova, N L; Bondarenko, P V; Zubarev, R A; Knysh, A N

    1993-03-01

    The 252-Cf plasma desorption mass spectrometry (252-Cf PDMS) determination or confirmation of the ginsenoside saponins has been proposed to investigate the composition of high performance liquid chromatography (HPLC) peaks of ginseng tinctures and galenic preparations. That ionization technique is well suitable for the analysis of natural mixtures of these saponins. The 252-Cf PD mass spectra of standard ginsenosides Rb1, Rb2, Rc, Re, Rg1, Rd, NG-R2, Z-R1 contain the peaks of two types of ions, namely, molecular adduct ions (MAI) and aglycone ions. By mass the latter may be referred to either protopanaxadiol or protopanaxatriol. The masses of MAI and aglycone ions are determined by the carbohydrate chains. The collected HPLC fractions of P ginseng tincture can be tested for content of ginsenosides. After studying two MAI peaks from the 252-Cf PD mass spectra of the basic ginsenosides, an example of distinction between two galenic preparations from different Panax has been shown. PMID:8352021

  5. Validation of a dissolution method with RP-HPLC analysis for Perindopril erbumine and Indapamide combination tablet

    Directory of Open Access Journals (Sweden)

    Jain P.S.

    2012-01-01

    Full Text Available A Dissolution method with high performance liquid chromatography (HPLC analysis was validated for perindopril erbumine and indapamide in combination tablet formulation. The method was validated to meet requirements for a global regulatory filing and this validation included specificity, linearity, accuracy, precision, range, robustness and solution stability studies. The dissolution method, which uses USP apparatus 1 with basket rotating at 100 rpm, 1000 ml of phosphate buffer pH 6.8 as the dissolution medium, and reversed-phased HPLC was carried out at 50⁰C on a 4.6mm×250mm 5μm cyano column that contained USP packing L1 with acetonitrile: buffer pH 2.8::40:60 (v/v, as mobile phase. UV detector was set at 225 nm. A method was found to be selective, linear, accurate and precise in the specified ranges. Intra-day and inter-day variability for method was <2% RSD. This method was successfully used for quantification of perindopril erbumine and indapamide combination tablet formulations.

  6. Quantitative and Qualitative Analysis of Aconitum Alkaloids in Raw and Processed Chuanwu and Caowu by HPLC in Combination with Automated Analytical System and ESI/MS/MS

    OpenAIRE

    Aimin Sun; Bo Gao; Xueqing Ding; Chi-Ming Huang; Paul Pui-Hay But

    2012-01-01

    HPLC in combination with automated analytical system and ESI/MS/MS was used to analyze aconitine (A), mesaconitine (MA), hypaconitine (HA), and their benzoyl analogs in the Chinese herbs Caowu and Chuanwu. First, an HPLC method was developed and validated to determine A, MA, and HA in raw and processed Caowu and Chuanwu. Then an automated analytical system and ESI/MS/MS were applied to analyze these alkaloids and their semihydrolyzed products. The results obtained from automated analytical sy...

  7. Combined Reversed Phase HPLC, Mass Spectrometry, and NMR Spectroscopy for a Fast Separation and Efficient Identification of Phosphatidylcholines

    Directory of Open Access Journals (Sweden)

    Jan Willmann

    2011-01-01

    Full Text Available In respect of the manifold involvement of lipids in biochemical processes, the analysis of intact and underivatised lipids of body fluids as well as cell and tissue extracts is still a challenging task, if detailed molecular information is required. Therefore, the advantage of combined use of high-pressure liquid chromatography (HPLC, mass spectrometry (MS, and nuclear magnetic resonance (NMR spectroscopy will be shown analyzing three different types of extracts of the ubiquitous membrane component phosphatidylcholine. At first, different reversed phase modifications were tested on phosphatidylcholines (PC with the same effective carbon number (ECN for their applicability in lipid analysis. The results were taken to improve the separation of three natural PC extract types and a new reversed phase (RP-HPLC method was developed. The individual species were characterized by one- and two-dimensional NMR and positive or negative ion mode quadrupole time of flight (q-TOF-MS as well as MS/MS techniques. Furthermore, ion suppression effects during electrospray ionisation (ESI, difficulties, limits, and advantages of the individual analytical techniques are addressed.

  8. Combination of automatic HPLC-RIA method for determination of estrone and estradiol in serum.

    Science.gov (United States)

    Yasui, T; Yamada, M; Kinoshita, H; Uemura, H; Yoneda, N; Irahara, M; Aono, T; Sunahara, S; Mito, Y; Kurimoto, F; Hata, K

    1999-01-01

    We developed a highly sensitive assay for estrone and 17 beta-estradiol in serum. Estrone and 17 beta-estradiol, obtained by solid-phase extraction using a Sep pak tC18 cartridge, were purified by high-performance liquid chromatography (HPLC). Quantitation of estrone and 17 beta-estradiol were carried out by radioimmunoassay. Not insignificantly, this automatic system of extraction and HPLC succeeded in analyzing 80 samples a week. Intra-assay coefficients of variation (CV) for estrone and 17 beta-estradiol ranged from 19.5 to 28.7%, and from 8.5 to 13.7%, respectively. The minimum detectable dose for estrone and 17 beta-estradiol were 1.04 pg/ml and 0.64 pg/ml, respectively. The serum levels of 17 beta-estradiol using our method strongly correlated with those by Gas chromatography mass spectrometry (GC-MS). The serum levels of estrone and 17 beta-estradiol in 154 peri- and postmenopausal women were estimated to be between 15 and 27 pg/ml and between 3.5 and 24.0 pg/ml, respectively, while the serum level of 17 beta-estradiol in postmenopausal women, in particular, was estimated to be from 3.5 to 6.3 pg/ml. For postmenopausal women who suffered from vasomotor symptoms, the mean levels of estrone and 17 beta-estradiol at 12 to 18 hours after treatment with daily 0.625 mg conjugated equine estrogen (CEE) and 2.5 mg medroxyprogesterone acetate (MPA) were 135.0 and 21.3 pg/ml at 12 months, respectively. On the other hand, levels of estrone and 17 beta-estradiol at 12 to 18 hours after treatment with CEE and MPA every other day, were 73.4 and 15.3 pg/ml, respectively. These highly sensitive assays for estrone and 17 beta-estradiol are useful in measuring low levels of estrogen in postmenopausal women, and monitoring estrogen levels in women receiving CEE as hormone replacement therapy. PMID:10633293

  9. Stability-indicating RP-HPLC method for simultaneous determination of gatifloxacin and flurbiprofen in binary combination

    Directory of Open Access Journals (Sweden)

    Islam Ullah Khan

    2014-04-01

    Full Text Available A stability-indicating RP-HPLC method is presented for determination of gatifloxacin and flurbiprofen in binary combination. Gatifloxacin, flurbiprofen and their degradation products were detected at 254 nm using a BDS Hypersil C8 (250 X 4.6 mm, 5 µm column and mixture of 20 mM phosphate buffer (pH 3.0 and methanol 30:70 v/v as mobile phase. Response was linear over the range of 15-105 mg mL-1 for gatifloxacin (r² > 0.998 and of 1.5-10.5 mg mL-1 for flurbiprofen (r² > 0.999. The developed method efficiently separated the analytical peaks from degradation products (peak purity index > 0.9999. The method developed can be applied successfully for determination of gatifloxacin and flurbiprofen in human serum, urine, pharmaceutical formulations, and their stability studies.

  10. Development of an HPLC-UV Method for the Analysis of Drugs Used for Combined Hypertension Therapy in Pharmaceutical Preparations and Human Plasma

    OpenAIRE

    Serife Evrim Kepekci Tekkeli

    2013-01-01

    A simple, rapid, and selective HPLC-UV method was developed for the determination of antihypertensive drug substances: amlodipine besilat (AML), olmesartan medoxomil (OLM), valsartan (VAL), and hydrochlorothiazide (HCT) in pharmaceuticals and plasma. These substances are mostly used as combinations. The combinations are found in various forms, especially in current pharmaceuticals as threesome components: OLM, AML, and HCT (combination I) and AML, VAL, and HCT (combination II). The separation...

  11. Determination of tissue distribution of potent antitumor agent ureidomustin (BO-1055) by HPLC and its pharmacokinetic application in rats.

    Science.gov (United States)

    Chien, Shin-I; Yen, Jiin-Cherng; Kakadiya, Rajesh; Chen, Ching-Huang; Lee, Te-Chang; Su, Tsann-Long; Tsai, Tung-Hu

    2013-02-15

    Ureidomustin hydrochloride (BO-1055) was designed as a water-soluble nitrogen-mustard, which exhibited potent anticancer activity and was selected as a candidate for preclinical studies. However, up to date, there is rarely an easy and economic method to quantize ureidomustin in the biological samples. The aim of this study is to develop a simple yet valid quantization method to tackle this challenge. Here we present a combined high-performance liquid chromatography with photodiode array (HPLC-PDA) method in quantizing the ureidomustin in the plasma and various organs of Sprague-Dawley rats. The method was validated in terms of precision, accuracy, and extraction recovery. Furthermore, the established method was applied to study pharmacokinetics of ureidomustin in the rat's plasma and verified via a liquid chromatography tandem mass spectrometry (LC-MS/MS) method. Calibration curves of the plasma and organ samples were falling at the range between 0.5-50μg/mL and 0.1-50μg/mL (r(2)≥0.999 and CV≤±15%), respectively. The limits of detection (LOD) were 0.1μg/mL for plasma samples and 0.05μg/mL for organ samples, while the detection limits of quantification (LOQ) were 0.5μg/mL for plasma samples and 0.1μg/mL for organ samples. The average recovery of ureidomustin was about 83%. These results demonstrated a linear pharmacokinetic pattern at dosages of 10 and 30mg/kg. The pharmacokinetic data revealed that ureidomustin was best fitted to a two-compartment model with a rapid distribution phase and a slow elimination phase. Besides, after a short intravenous administration time at the dose of 10mg/kg, ureidomustin was found to be quickly distributed to all organs in rats, accumulated mainly in the kidney, and only a limited amount was detected in the brain. PMID:23353940

  12. Development of fixed dose combination tablets of aripiprazole plus divalproex sodium and their simultaneous determination using HPLC-UV.

    Science.gov (United States)

    Ahmed, Zia; Subhan, Fazal; Ahmed, Saba; Abdur Rasheed, Qazi; Ahmed, Sagheer; Shahid, Muhammad; Farooq, Saeed

    2016-09-01

    A vast majority of psychiatric patients are effectively treated with combination of drugs to improve efficacy and adherence, but due to limited research and development in fixed dose combination (FDC) in psychiatry, these products are not commonly available. The aim of this study is to prepare cost effective FDC tablets containing aripiprazole and divalproex sodium. Two batches of fixed dose combination tablets, FDC1 and FDC2, were successfully prepared using wet granulation technique. Furthermore, aripiprazole tablets A1 and A2 and divalproex tablets D1 were also formulated as reference to compare the in vitro availability profile. An accurate and simple isocratic HPLC method was established and validated for the simultaneous quantification of aripiprazole and valproic acid in the FDC tablets. A reversed-phase C18 (250 × 4.6 mm) column in isocratic mode was used. The mobile phase consisted of acetonitrile and 0.32% KH2PO4 (60:40, v/v), flow rate was set at 1.0 mL/min and the detection was performed at 210 nm. Average percent recoveries of aripiprazole and valproic acid were 96.0 and 95.5%, respectively, meeting the official requirements. The newly developed FDC product may be used for the better therapeutic outcomes of combined use of aripiprazole and valproic acid, which may improve patient adherence. PMID:26727505

  13. Development and validation of a repharsed phase- HPLC method for simultaneous determination of rosiglitazone and glimepiride in combined dosage forms and human plasma

    Directory of Open Access Journals (Sweden)

    El-Enany Nahed M

    2012-01-01

    Full Text Available Abstract Background Rosiglitazone (ROZ and glimepiride (GLM are antidiabetic agents used in the treatment of type 2 diabetes mellitus. A survey of the literature reveals that only one spectrophotometric method has been reported for the simultaneous determination of ROS and GLM in pharmaceutical preparations. However the reported method suffers from the low sensitivity, for this reason, our target was to develop a simple sensitive HPLC method for the simultaneous determination of ROZ and GLM in their combined dosage forms and plasma. Results A simple reversed phase high performance liquid chromatographic (RP-HPLC method was developed and validated for the simultaneous determination of Rosiglitazone (ROS and Glimepiride (GLM in combined dosage forms and human plasma. The separation was achieved using a 150 mm × 4.6 mm i.d., 5 μm particle size Symmetry® C18 column. Mobile phase containing a mixture of acetonitrile and 0.02 M phosphate buffer of pH 5 (60: 40, V/V was pumped at a flow rate of 1 mL/min. UV detection was performed at 235 nm using nicardipine as an internal standard. The method was validated for accuracy, precision, specificity, linearity, and sensitivity. The developed and validated method was successfully used for quantitative analysis of Avandaryl™ tablets. The chromatographic analysis time was approximately 7 min per sample with complete resolution of ROS (tR = 3.7 min., GLM (tR = 4.66 min., and nicardipine (tR, 6.37 min. Validation studieswas performed according to ICH Guidelines revealed that the proposed method is specific, rapid, reliable and reproducible. The calibration plots were linear over the concentration ranges 0.10-25 μg/mL and 0.125-12.5 μg/mL with LOD of 0.04 μg/mL for both compounds and limits of quantification 0.13 and 0.11 μg/mL for ROS and GLM respectively. Conclusion The suggested method was successfully applied for the simultaneous analysis of the studied drugs in their co-formulated tablets and human

  14. Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

    OpenAIRE

    Jialian Li; Yongqing Zhang; Yunliang Lin; Xiao Wang; Lei Fang; Yanling Geng; Qinde Zhang

    2013-01-01

    Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC) combined with preparative HPLC (prep-HPLC). First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether - ethyl acetate - methanol - water (4:6:4:6, 4:6:5:5, v/v) was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further...

  15. Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jialian; Zhang, Yongqing, E-mail: fleiv@163.com [College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, Shandong (China); Lin, Yunliang; Wang, Xiao; Fang, Lei; Geng, Yanling [Shandong Analysis and Test Center, Shandong Academy of Sciences, Jinan, Shandong (China); Zhang, Qinde [Shandong College of Traditional Chinese Medicine, Laiyang, Shandong (China)

    2013-09-01

    Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC) combined with preparative HPLC (prep-HPLC). First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether-ethyl acetate-methanol-water (4:6:4:6, 4:6:5:5, v/v) was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further separated by prepHPLC, respectively, and another four bufadienolides were recovered. Their structures were confirmed by ESI-MS and {sup 1}H-NMR spectra. (author)

  16. Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

    Directory of Open Access Journals (Sweden)

    Jialian Li

    2013-01-01

    Full Text Available Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC combined with preparative HPLC (prep-HPLC. First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether - ethyl acetate - methanol - water (4:6:4:6, 4:6:5:5, v/v was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further separated by prep-HPLC, respectively, and another four bufadienolides were recovered. Their structures were confirmed by ESI-MS and ¹H-NMR spectra.

  17. Comprehensive Assessment of Degradation Behavior of Aspirin and Atorvastatin Singly and in Combination by Using a Validated RP-HPLC Method

    OpenAIRE

    Sherikar, Omkar; Mehta, Priti

    2012-01-01

    A fixed-dose combination of atorvastatin and aspirin is widely used for the treatment of myocardial infarction. The present work describes a comprehensive study of the stress degradation behavior of atorvastatin and aspirin alone as well as in combination of 1:1 and 1:7.5 ratios, respectively, as per ICH guidelines. The degradation products of aspirin as well as atorvastatin were successfully separated by a developed simple, selective, and precise stability-indicating reversed-phase HPLC meth...

  18. HPLC-PDA法检测蒲黄和黄连中十种非法添加色素%Determination of ten colouring agent in pollen typhae and pollen typhae with HPLC-PDA

    Institute of Scientific and Technical Information of China (English)

    郑娟; 邹耀华

    2011-01-01

    目的:建立HPLC-PDA法测定蒲黄和黄连中非法添加色素金橙G、日落黄、金橙Ⅰ、亮黄、甲基橙、金橙Ⅱ、金橙Ⅳ、金莲橙G、金胺O、二甲基黄的方法.方法:样品用70%乙醇溶液提取,以甲醇-0.05 mol/L醋酸铵溶液梯度洗脱,二极管阵列检测器检测.结果:该方法检出限为0.026 mg/kg~0.950 mg/kg,2档添加回收率为81.5%~104.7%;市售蒲黄和黄连中多批次检出金胺O.结论:本实验采用HPLC-PDA法同时检测蒲黄和黄连等黄色类中药材(饮片)中十种常用的非法添加色素,方法简单、准确、快速,可以为制药企业或药品监督管理部门控制蒲黄和黄连的质量提供一定的参考.%Objective:A method for rapid determination of ten colouring agent in Pollen Typhae and Pollen Typhae (included Orange G,Sunset Yellow,Orange Ⅰ ,brilliant yellow, Methyl Orange,Orange Ⅱ ,Orange Ⅳ ,Tropaeolin G,Auramine O ,Dimethyl Yellow) was developed. Methods: The sample was extracted by 70% ethanol,gradient elution with methanol and 0.05 mol/L ammonium acetate and then detected by Photo - Diode Array Detector. Results: The limits of quantitation (LOQs) of the method were 0. 026 mg/kg ~0. 950 mg/kg, and fortified recovery of reference substance solutions at two levels were 81.5% ~ 104.7%,the RSDs were below 2.0% ( n = 3). Ten reference substance solutions were separated well in fifty minutes. Auramine O was detected in multi -batch of Pollen Typhae and Pollen Typhae. Conclusion: This method is simple, rapid,and reproducible, and it can be used as a low -cost, convenient method for measuring colouring agent in Saffron and Safflower, and it can provide reference or help for relative company and State food and drug administration.

  19. Determination of the absolute configuration of selenomethionine from antarctic krill by RP-HPLC/ICP-MS using chiral derivatization agents

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, Jan; Lassen, Stephan; Prange, Andreas [GKSS Research Center Geesthacht, Institute for Coastal Research, Max-Planck Strasse, 21502, Geesthacht (Germany)

    2004-03-01

    A fast and sensitive method was developed for the determination of the absolute configuration of selenomethionine. The enantiomers of selenomethionine were converted into diastereomeric isoindole derivatives by reaction with o-phthaldialdehyde and N-isobutyryl-l-cysteine. This easy-to-handle reaction proceeds quantitatively in a few minutes at room temperature. Separation and detection of the diastereomers was achieved by reversed-phase high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (RP-HPLC/ICP-MS) using a conventional C18 reversed-phase column. Detection limits of about 4 {mu}g L{sup -1} were obtained. The method was applied to the determination of the configuration of selenomethionine extracted from antarctic krill, which turned out to possess the l-configuration. (orig.)

  20. Crisis response simulation combining discrete-event and agent-based modeling

    NARCIS (Netherlands)

    Gonzalez, R.A.

    2009-01-01

    This paper presents a crisis response simulation model architecture combining a discrete-event simulation (DES) environment for a crisis scenario with an agent-based model of the response organization. In multi-agent systems (MAS) as a computational organization, agents are modeled and implemented s

  1. HPLC method development for the simultaneous analysis of amlodipine and valsartan in combined dosage forms and in vitro dissolution studies

    Directory of Open Access Journals (Sweden)

    Mustafa Çelebier

    2010-12-01

    Full Text Available A simple, rapid and reproducible HPLC method was developed for the simultaneous determination of amlodipine and valsartan in their combined dosage forms, and for drug dissolution studies. A C18 column (ODS 2, 10 μm, 200 x 4.6 mm and a mobile phase of phosphate buffer (pH 3.6 , 0.01 mol L-1:acetonitrile: methanol (46:44:10 v/v/v mixture were used for separation and quantification. Analyses were run at a flow-rate of 1 mL min-1 and at ambient temperature. The injection volume was 20 μL and the ultraviolet detector was set at 240 nm. Under these conditions, amlodipine and valsartan were eluted at 7.1 min and 3.4 min, respectively. Total run time was shorter than 9 min. The developed method was validated according to the literature and found to be linear within the range 0.1 - 50 μg mL-1 for amlodipine, and 0.05 - 50 μg mL-1 for valsartan. The developed method was applied successfully for quality control assay of amlodipine and valsartan in their combination drug product and in vitro dissolution studies.Desenvolveu-se método de HPLC rápido e reprodutível para a determinação simultânea de anlodipino e valsartana em suas formas de associação e para os estudos de dissolução dos fármacos. Utilizaram-se coluna C18 (ODS 2, 10 μm, 200 x 4,6 mm e fase móvel tampão fosfato (pH 3,6, 0,01 mol L-1:acetonitrila: metanol para a separação e a quantificação. As análises foram efetuadas com velocidade de fluxo de 1 mL min-1 e à temparatura ambiente O volume de injeção foi de 20 μL e utilizou-se detector de ultravioleta a 240 nm. Sob essas condições, anlodipino e valsartana foram eluídas a 7,1 min e 3,4 min, respectivamente. O tempo total de corrida foi menor que 9 min. O método desenvolvido foi validado de acordo com a literatura e se mostrou linear na faixa de 0,1-50 μg mL-1 para anlodipino e de 0,05-50 μg mL-1 para valsartana. O método desenvolvido foi aplicado com sucesso para ensaios de controle de qualidade de associações de

  2. Antiangiogenic agents combined with chemotherapy in non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    Shanshan Chen; Shun Lu 

    2015-01-01

    As a targeted therapy, antiangiogenic treatment has been increasingly studied for advanced non-smal cel lung cancer (NSCLC) and has proven ef ective for the treatment of advanced NSCLC. Bevacizumab, a monoclonal antibody targeting angiogenesis, is the only antiangiogenic agent approved for use in com-bination with first-line chemotherapy for non-squamous NSCLC. Smal-molecule inhibitors targeting the tyrosine kinase receptor have also shown promise when combined with standard chemotherapeutic agents in patients with advanced NSCLC. However, unlike bevacizumab, not al other antiangiogenic agents show significant benefits when combined with chemotherapy. As for the failures of most other combinations, the combination schedule may be an important reason that has so far been overlooked in clinical trials. This article reviews the combination of angiogenic agents with chemotherapy in the treatment of NSCLC.

  3. HPLC-TOF-MS and HPLC-MS/MS combined with multivariate analysis for the characterization and discrimination of phenolic profiles in nonfumigated and sulfur-fumigated rhubarb.

    Science.gov (United States)

    Yan, Yan; Zhang, Qianqian; Feng, Fang

    2016-07-01

    Sulfur fumigation has recently been used during the postharvest handling of rhubarb to reduce the drying duration and control pests. However, a few reports question the effect of sulfur fumigation on the bioactive components of rhubarb, which is crucial for the quality evaluation of the herbal medicine. The bottleneck limiting the study comes from the complex compounds that exist in herb samples with diverse structural features, wide concentration range and the difficulty to obtain all the reference standards. In this study, an integrated strategy based on the highly effective separation and analysis by liquid chromatography coupled with diode-array detection and time-of-flight/triple-quadruple tandem mass spectrometry combined with multivariate analysis was established. 68 phenolic compounds that exist in nonfumigated and sulfur-fumigated herb samples of rhubarb were tentatively assigned based on their retention behavior, UV spectra, accurate molecular weight, and mass spectral fragments. Qualitative and semiquantitative comparison revealed a serious reduction of the majority of phenolic compounds in sulfur-fumigated rhubarb. Furthermore, multivariate analysis was applied to holistically discriminate nonfumigated from sulfur-fumigated rhubarb and explore the characteristic chemical markers. The established approach was specific and rapid for characterizing and screening sulfur-fumigated rhubarb among commercial samples and could be applied for the quality assessment of other sulfur-fumigated herbs. PMID:27173451

  4. Antiangiogenic agents in the treatment of recurrent or newly diagnosed glioblastoma: Analysis of single-agent and combined modality approaches

    International Nuclear Information System (INIS)

    Surgical resection followed by radiotherapy and temozolomide in newly diagnosed glioblastoma can prolong survival, but it is not curative. For patients with disease progression after frontline therapy, there is no standard of care, although further surgery, chemotherapy, and radiotherapy may be used. Antiangiogenic therapies may be appropriate for treating glioblastomas because angiogenesis is critical to tumor growth. In a large, noncomparative phase II trial, bevacizumab was evaluated alone and with irinotecan in patients with recurrent glioblastoma; combination treatment was associated with an estimated 6-month progression-free survival (PFS) rate of 50.3%, a median overall survival of 8.9 months, and a response rate of 37.8%. Single-agent bevacizumab also exceeded the predetermined threshold of activity for salvage chemotherapy (6-month PFS rate, 15%), achieving a 6-month PFS rate of 42.6% (p < 0.0001). On the basis of these results and those from another phase II trial, the US Food and Drug Administration granted accelerated approval of single-agent bevacizumab for the treatment of glioblastoma that has progressed following prior therapy. Potential antiangiogenic agents-such as cilengitide and XL184-also show evidence of single-agent activity in recurrent glioblastoma. Moreover, the use of antiangiogenic agents with radiation at disease progression may improve the therapeutic ratio of single-modality approaches. Overall, these agents appear to be well tolerated, with adverse event profiles similar to those reported in studies of other solid tumors. Further research is needed to determine the role of antiangiogenic therapy in frontline treatment and to identify the optimal schedule and partnering agents for use in combination therapy

  5. HPLC-UV Method for the Identification and Screening of Hydroquinone, Ethers of Hydroquinone and Corticosteroids Possibly Used as Skin-Whitening Agents in Illicit Cosmetic Products.

    Science.gov (United States)

    Gimeno, Pascal; Maggio, Annie-Françoise; Bancilhon, Marjorie; Lassu, Nelly; Gornes, Hervé; Brenier, Charlotte; Lempereur, Laurent

    2016-03-01

    Corticosteroids, hydroquinone and its ethers are regulated in cosmetics by the Regulation 1223/2009. As corticosteroids are forbidden to be used in cosmetics and cannot be present as contaminants or impurities, an identification of one of these illicit compounds deliberately introduced in these types of cosmetics is enough for market survey control. In order to quickly identify skin-whitening agents present in illegal cosmetics, this article proposes an HPLC-UV method for the identification and screening of hydroquinone, 3 ethers of hydroquinone and 39 corticosteroids that may be found in skin-whitening products. Two elution gradients were developed to separate all compounds. The main solvent gradient (A) allows the separation of 39 compounds among the 43 compounds considered in 50 min. Limits of detection on skin-whitening cosmetics are given. For compounds not separated, a complementary gradient elution (B) using the same solvents is proposed. Between 2004 and 2009, a market survey on "skin-whitening cosmetic" was performed on 150 samples and highlights that more than half of the products tested do not comply with the Cosmetic Regulation 1223/2009 (amending the Council Directive 76/768/EEC). PMID:26462503

  6. Anti static agent characterization in polypropylene by using combined instrumental techniques

    International Nuclear Information System (INIS)

    Antistatic agents are substances with are added to plastics molding formulations or to the surface of molded articles to minimize the accumulation of static electricity. The analysis and characterization of an antistatic agent in polypropylene using combined techniques provides very specific and detailed information. (author)

  7. Alternative chromatographic processes for no-carrier added 177Lu radioisotope separation. Part 2. The conventional column chromatographic separation combined with HPLC for high purity

    International Nuclear Information System (INIS)

    HPLC technique combined with the simple conventional column solid phase extraction (SPE) chromatography using di-(2-ethylhexyl)orthophosphoric acid (HDEHP) impregnated OASIS-HLB sorbent based SPE resins (OASIS-HDEHP ) was developed for the separation of no-carrier added (n.c.a) 177Lu from the bulk quantity of ytterbium target. This combination strategy was based on combining the advantages of the better resolution of HPLC separation of n.c.a 177Lu from the few milligram level Yb target with the high capacity of the OASISHDEHP column for the separation of 177Lu from the bulk Yb target. The production batches of several hundred mCi activity of n.c.a 177Lu radioisotope separated from 50 mg Yb target activated in a nuclear reactor of medium neutron flux (Φ = 5 x 1013 n x cm-2 x s-1) were successfully performed using this combined separation technique. With the target irradiation in a reactor of higher thermal neutron flux or with the parallel run of several separation units, several Ci-s of n.c.a 177Lu can be profitably produced on a commercial production basis. (author)

  8. DEVELOPMENT AND VALIDATION OF TLC-DENSITOMETRIC AND HPLC METHODS FOR DETERMINATION OF OLMESARTAN MEDOXOMIL AND METOPROLOL SUCCINATE IN COMBINATION

    OpenAIRE

    Chitlange Sohan S.; Talole Reshma A.; Bhusal Ramesh D.; Nikumbh Monesh B.

    2012-01-01

    Rapid, accurate and sensitive methods for the identification and quantification of Olmesartan Medoxomil (OLME) and Metoprolol Succinate (METO) were developed by TLC-densitometry and HPLC at 222 nm. The first developed method was TLC-densitometry, where mixture of OLME and METO were separated on silica gel TLC 60 F254 plates using Toluene:Methanol:Glacial acetic acid (7.0:2.5:0.5 v/v/v) as mobile phase and scanning of the separated bands at 222 nm. Linearity was observed in the concentration ...

  9. The combination of sodium perborate and water as intracoronal teeth bleaching agent

    Directory of Open Access Journals (Sweden)

    Ananta Tantri Budi

    2008-12-01

    Full Text Available Background: The color change on post-endodontic treated teeth can be overcome by intracoronal tooth bleaching using walking bleach. Some agents used in walking bleach are combination of sodium peroxide and hydrogen peroxide, and combination of sodium perborate and water. Purpose: The objective of this review is to provide information and consideration of using safe and effective bleaching agents in the field of dentistry. Reviews: On one side, the use of sodium perborate and water combination does not cause the reduction of dentin hardness, enamel decay, and root resorbtion. On the other side, the use of sodium perborate and 30% hydrogen peroxide combination indicates that it takes longer time in yielding the proper color of teeth. Conclusion: The use of sodium perborate and water combination as bleaching agents is effective and safe.

  10. A Bayesian Dose-finding Design for Oncology Clinical Trials of Combinational Biological Agents.

    Science.gov (United States)

    Cai, Chunyan; Yuan, Ying; Ji, Yuan

    2014-01-01

    Treating patients with novel biological agents is becoming a leading trend in oncology. Unlike cytotoxic agents, for which efficacy and toxicity monotonically increase with dose, biological agents may exhibit non-monotonic patterns in their dose-response relationships. Using a trial with two biological agents as an example, we propose a dose-finding design to identify the biologically optimal dose combination (BODC), which is defined as the dose combination of the two agents with the highest efficacy and tolerable toxicity. A change-point model is used to reflect the fact that the dose-toxicity surface of the combinational agents may plateau at higher dose levels, and a flexible logistic model is proposed to accommodate the possible non-monotonic pattern for the dose-efficacy relationship. During the trial, we continuously update the posterior estimates of toxicity and efficacy and assign patients to the most appropriate dose combination. We propose a novel dose-finding algorithm to encourage sufficient exploration of untried dose combinations in the two-dimensional space. Extensive simulation studies show that the proposed design has desirable operating characteristics in identifying the BODC under various patterns of dose-toxicity and dose-efficacy relationships. PMID:24511160

  11. DEVELOPMENT AND VALIDATION OF TLC-DENSITOMETRIC AND HPLC METHODS FOR DETERMINATION OF OLMESARTAN MEDOXOMIL AND METOPROLOL SUCCINATE IN COMBINATION

    Directory of Open Access Journals (Sweden)

    Chitlange Sohan S.

    2012-06-01

    Full Text Available Rapid, accurate and sensitive methods for the identification and quantification of Olmesartan Medoxomil (OLME and Metoprolol Succinate (METO were developed by TLC-densitometry and HPLC at 222 nm. The first developed method was TLC-densitometry, where mixture of OLME and METO were separated on silica gel TLC 60 F254 plates using Toluene:Methanol:Glacial acetic acid (7.0:2.5:0.5 v/v/v as mobile phase and scanning of the separated bands at 222 nm. Linearity was observed in the concentration range of 500-2500 ng/band for OLME and 500-3000 ng/band for METO. The second method was HPLC, where the mixture of OLME and METO separated on thermo scientific BDS Hypersil, C18 column (5µm p.s, 250 mm  4.6 mm, flow rate 1 mL/min. The mobile phase selected was Phosphate buffer 0.05M (pH adjusted to 3.0±0.5 with Orthophosphoric acid: Acetonitrile (60:40 v/v with detection at 222 nm. Linearity was observed in the concentration range of 25-200 µg/mL for OLME and 25-225 µg/mL for METO. Both methods were validated according to ICH guideline and value of linearity, precision, robustness, LOD, LOQ, selectivity, recovery were found to be good in accordance with the prescribed value.

  12. Development of HPLC and UV spectrophotometric methods for the determination of ascorbic acid using hydroxypropyl-β-cyclodextrin and triethanolamine as photostabilizing agents

    International Nuclear Information System (INIS)

    In this study, the effect of complex formation with triethanolamine (TEA) alone and in combination with hydroxypropyl-β-cyclodextrin (HP-β-CD) on the photostability of ascorbic acid was evaluated for exposure to artificial and diffuse daylight. The first-order rate constants for the photodegradation reactions were determined. The data obtained showed that these complexes strongly reduced the photodegradation process with an 11- and 35-fold increase in the photostability of ascorbic acid, depending of the ligand concentration and the irradiation source. The multicomponent complex gave a significantly better stabilization for exposure to light than TEA alone. Due to the fact that the complexation extended the exposure of ascorbic acid to light (without molecular changes), UV spectrophotometric and reversed phase high performance liquid chromatographic (HPLC) methods were developed for the quantitative determination of the vitamin in pure form and in pharmaceutical preparations. These methods were statistically validated, all the validation parameters were found to be within the acceptance range. These results demonstrate that the proposed methods are suitable for the quality control of ascorbic acid, providing simple, rapid, precise, accurate and convenient approaches for routine analysis of bulk drug and pharmaceutical formulations.

  13. In silico attempt for adduct agent(s) against malaria: Combination of chloroquine with alkaloids of Adhatoda vasica.

    Science.gov (United States)

    Swain, Shasank S; Sahu, Mahesh C; Padhy, Rabindra N

    2015-10-01

    With the aim of controlling drug resistant Plasmodium falciparum, a computational attempt of designing novel adduct antimalarial drugs through the molecular docking method of combining chloroquine with five alkaloids, individually is presented. These alkaloids were obtained from the medicinal plant, Adhatoda vasica. From the obtained individual docking values of important derivatives of quinine and chloroquine, as well as, individual alkaloids and adduct agents of chloroquine with Adhatoda alkaloids as ligands, it was discernible that the 'adduct agent-1 with chloroquine and adhatodine' combination had the minimum energy of interaction, as the docking score value of -11.144 kcal/mol against the target protein, triosephosphate isomerase (TIM), the key enzyme of glycolytic pathway. Drug resistance of P. falciparum is due to a mutation in the polypeptide of TIM. Moratorium of mutant TIM would disrupt the metabolism during the control of the drug resistant P. falciparum. This in silico work helped to locate the 'adduct agent-1 with chloroquine and adhatodine', which could be taken up by pharmacology for further development of this compound as a new drug against drug resistant Plasmodium. PMID:26142781

  14. Combining Human and Machine Intelligence to Derive Agents' Behavioral Rules for Groundwater Irrigation

    Science.gov (United States)

    Hu, Y.; Quinn, C.; Cai, X.

    2015-12-01

    One major challenge of agent-based modeling is to derive agents' behavioral rules due to behavioral uncertainty and data scarcity. This study proposes a new approach to combine a data-driven modeling based on the directed information (i.e., machine intelligence) with expert domain knowledge (i.e., human intelligence) to derive the behavioral rules of agents considering behavioral uncertainty. A directed information graph algorithm is applied to identifying the causal relationships between agents' decisions (i.e., groundwater irrigation depth) and time-series of environmental, socio-economical and institutional factors. A case study is conducted for the High Plains aquifer hydrological observatory (HO) area, U.S. Preliminary results show that four factors, corn price (CP), underlying groundwater level (GWL), monthly mean temperature (T) and precipitation (P) have causal influences on agents' decisions on groundwater irrigation depth (GWID) to various extents. Based on the similarity of the directed information graph for each agent, five clusters of graphs are further identified to represent all the agents' behaviors in the study area as shown in Figure 1. Using these five representative graphs, agents' monthly optimal groundwater pumping rates are derived through the probabilistic inference. Such data-driven relationships and probabilistic quantifications are then coupled with a physically-based groundwater model to investigate the interactions between agents' pumping behaviors and the underlying groundwater system in the context of coupled human and natural systems.

  15. Quantization of dextromethorphan and levocetirizine in combined dosage form using a novel validated RP-HPLC method

    Directory of Open Access Journals (Sweden)

    Shalini Joshi

    2012-01-01

    Full Text Available The present study reveals a simple isocratic RP-HPLC method for the simultaneous determination of dextromethorphan hydrobromide and levocetirizine dihydrochloride in a cough syrup. The separation of these compounds was achieved within 10 min on a Phenomenex (USA C 18 analytical column, 250Χ4.0 mm i.d., using an isocratic mobile phase consisting of potassium dihydrogen phosphate buffer (pH 2.5 - acetonitrile- tetrahydrofuran (70:25:5, v/v/v. The analysis was performed at a flow rate of 1.2 ml/min and at a detection wavelength of 232 nm. Percentage recovery and RSD were 100.36% and 0.05% for levocetirizine dihydrochloride, 100.35% and 0.27% for dextromethorphan hydrobromide respectively. Quantification of the components in syrup formulation was calculated against the peak areas of freshly prepared standard solutions. The method was validated as per ICH guidelines.

  16. Quantization of Dextromethorphan and Levocetirizine in Combined Dosage form Using a Novel Validated RP-HPLC Method.

    Science.gov (United States)

    Joshi, Shalini; Bhatia, C; Bal, C S; Rawat, M S M

    2012-01-01

    The present study reveals a simple isocratic RP-HPLC method for the simultaneous determination of dextromethorphan hydrobromide and levocetirizine dihydrochloride in a cough syrup. The separation of these compounds was achieved within 10 min on a Phenomenex (USA) C(18) analytical column, 250×4.0 mm i.d., using an isocratic mobile phase consisting of potassium dihydrogen phosphate buffer (pH 2.5) - acetonitrile- tetrahydrofuran (70:25:5, v/v/v). The analysis was performed at a flow rate of 1.2 ml/min and at a detection wavelength of 232 nm. Percentage recovery and RSD were 100.36% and 0.05% for levocetirizine dihydrochloride, 100.35% and 0.27% for dextromethorphan hydrobromide respectively. Quantification of the components in syrup formulation was calculated against the peak areas of freshly prepared standard solutions. The method was validated as per ICH guidelines. PMID:23204629

  17. Combined effect of levan and cytotoxic agents on the growth of experimental tumours in mice.

    OpenAIRE

    Leibovici, J.; Stark, Y.; Wolman, M.

    1983-01-01

    The combined effect of the polysaccharide levan (previously shown to exert a host-dependent as well as direct antitumoural activity) and the cytotoxic agents cyclophosphamide (CY), methotrexate (MTX), vincristine (VINC) and 5-fluoro-uracil (SFU) was studied in Lewis lung carcinoma and AKR lymphoma. Combined chemo- and immunotherapy was applied beginning on the day of tumour cell inoculation. Additive effects were obtained with the combined treatments, compared to single treatments, with all t...

  18. A Dynamic Cordon Pricing Scheme combining a Macroscopic and an Agent-based traffic Models

    OpenAIRE

    Zheng, Nan; Waraich, Rashid A.; Axhausen, Kay W.; Geroliminis, Nikolaos

    2012-01-01

    Pricing is considered an effective management policy to reduce traffic congestion in transportation networks. In this paper we combine a macroscopic model of traffic congestion in urban networks with an agent-based simulator to study congestion pricing schemes. The macroscopic model, which has been tested with real data in previous studies, represents an accurate and robust approach to model the dynamics of congestion. The agent-based simulator can reproduce the complexity of travel behavior ...

  19. Quantitative and Qualitative Analysis of Aconitum Alkaloids in Raw and Processed Chuanwu and Caowu by HPLC in Combination with Automated Analytical System and ESI/MS/MS

    Directory of Open Access Journals (Sweden)

    Aimin Sun

    2012-01-01

    Full Text Available HPLC in combination with automated analytical system and ESI/MS/MS was used to analyze aconitine (A, mesaconitine (MA, hypaconitine (HA, and their benzoyl analogs in the Chinese herbs Caowu and Chuanwu. First, an HPLC method was developed and validated to determine A, MA, and HA in raw and processed Caowu and Chuanwu. Then an automated analytical system and ESI/MS/MS were applied to analyze these alkaloids and their semihydrolyzed products. The results obtained from automated analytical system are identical to those from ESI/MS/MS, which indicated that the method is a convenient and rapid tool for the qualitative analysis of herbal preparations. Furthermore, HA was little hydrolyzed by heating processes and thus it might account more for the toxicity of processed aconites. Hence, HA could be used as an indicator when one alkaloid is required as a reference to monitor the quality of raw and processed Chuanwu and Caowu. In addition, the raw and processed Chuanwu and Caowu can be distinguished by monitoring the ratio of A and MA to HA.

  20. Simultaneous extraction, identification and quantification of phenolic compounds in Eclipta prostrata using microwave-assisted extraction combined with HPLC-DAD-ESI-MS/MS.

    Science.gov (United States)

    Fang, Xinsheng; Wang, Jianhua; Hao, Jifu; Li, Xueke; Guo, Ning

    2015-12-01

    A simple and rapid method was developed using microwave-assisted extraction (MAE) combined with HPLC-DAD-ESI-MS/MS for the simultaneous extraction, identification, and quantification of phenolic compounds in Eclipta prostrata, a common herb and vegetable in China. The optimized parameters of MAE were: employing 50% ethanol as solvent, microwave power 400 W, temperature 70 °C, ratio of liquid/solid 30 mL/g and extraction time 2 min. Compared to conventional extraction methods, the optimized MAE can avoid the degradation of the phenolic compounds and simultaneously obtained the highest yields of all components faster with less consumption of solvent and energy. Six phenolic acids, six flavonoid glycosides and one coumarin were firstly identified. The phenolic compounds were quantified by HPLC-DAD with good linearity, precision, and accuracy. The extract obtained by MAE showed significant antioxidant activity. The proposed method provides a valuable and green analytical methodology for the investigation of phenolic components in natural plants. PMID:26041227

  1. Pharmacokinetics of kadsurenone and its interaction with cyclosporin A in rats using a combined HPLC and microdialysis system.

    Science.gov (United States)

    Huang, Shu-Pei; Lin, Lie-Chwen; Wu, Yu-Tse; Tsai, Tung-Hu

    2009-01-15

    Kadsurenone is a neolignan with specific antagonistic activity of platelet-activating factor, and is derived from the stems of Piper kadsura. To investigate the mechanism of hepatobiliary excretion of kadsurenone and its association with P-glycoprotein (P-gp), and to explore whether the hepatobiliary excretion of kadsurenone was associated with P-gp, a microdialysis system coupled with HPLC was developed to measure free-form kadsurenone in rat blood and bile. This study design was parallel in the following groups: six rats received kadsurenone alone (20 and 30 mg/kg, i.v.) as control group and the treated-group rats were co-administered with kadsurenone and CsA; P-gp inhibitor. The microdialysis probes were respectively inserted into the jugular vein toward right atrium and bile duct of male Sprague-Dawley rats for blood and bile sampling. CsA (20mg/kg) was administered 10 min prior to kadsurenone administration through the femoral vein and the collected samples were analyzed by a HPLC system. The analytes were separated by a C18 column (150 x 4.6 mm I.D., 5 microm) with a mobile phase of acetonitrile-water (50:50, v/v) at a flow-rate of 1 mL/min. The UV detection wavelength was set 235 nm. The calibration curve was linear over the concentration range of 0.05-10 microg/mL with the coefficient of determination of 0.997. The inter- and intra-assay accuracy and precision of the method ranged from -9.53% to 6.75%. The limit of detection and the limit of quantification were 0.01 and 0.05 microg/mL, respectively. The hepatobiliary excretion ratio of kadsurenone was defined by dividing the values of the area under the drug concentration curve (AUC) for bile and blood (AUC(bile)/AUC(blood)). The results indicated that the hepatobiliary excretion ratio of kadsurenone on the CsA treated-group was 1.2+/-0.1, which was not significantly different from the group of kadsurenone alone (1.3+/-0.2). This fact indicates that kadsurenone went through hepatobiliary excretion but might

  2. Derivative- Ratio Spectrophotometric, Chemometric and HPLC Validated methods for Simultaneous Determination of Amlodipine and Atorvastatin in Combined Dosage Form

    Directory of Open Access Journals (Sweden)

    Ola Moustafa Abdallah

    2011-04-01

    Full Text Available Three methods were developed for simultaneous determination of amlodipine and atorvastatin without previous separation. The first method depends on first derivative of the ratios spectra by measurements of the amplitudes at 228 and 245 nm for amlodipine using 25 μg/mL of atorvastatin as a divisor and at 284 and 295 nm for atorvastatin using 80 μg/mL of amlodipine as a divisor. Calibration graphs were established in the range of 10-100 μg/mL and 2.5-30 μg/mL for amlodipine and atorvastatin, respectively. The second method describes the use of multivariate spectophotometric calibration for the simultaneous determination of the analyzed binary mixture, where the resolution is accomplished by using partial least squares (PLS regression analysis. In the third method (HPLC, separation was performed by using C18 reversed phase column and a mobile phase of acetonitrile: 0.05 M KH2PO4 (60:40v/v adjusted by phosphoric acid to pH 3.5 at flow rate of 1 mL/min. All proposed methods were extensively validated and the results obtained by adopting the three methods were statistically analyzed and compared with those obtained from a reported method.

  3. Hollow-fiber micro-extraction combined with HPLC for the determination of sitagliptin in urine samples

    Directory of Open Access Journals (Sweden)

    Rezaee Raheme

    2015-01-01

    Full Text Available This study successfully developed a three-phase hollow-fiber liquid phase micro extraction coupled with high performance liquid chromatography for determination of trace levels of an anti-diabetic drug, sitagliptin (STG, in urine samples. Sitagliptin was extracted from 15 mL of the basic sample solution with a pH of 8.5 into an organic extracting solvent (n-octanol impregnated in the pores of a hollow fiber and then back extracted into an acidified aqueous solution in the lumen of the hollow fiber with a pH of 3. After extraction, 20 µL of the acceptor phase was injected into HPLC. In order to obtain high extraction efficiency, the parameters affecting the HF-LPME including pH of the source and receiving phases, type of organic phase, ionic strength, stirring rate, extraction time, the volume ratio of donor phase to acceptor phase and temperature were studied and optimized. Under the optimized conditions, enrichment factors up to 88 were achieved and the relative standard deviation of the method was in the range of 3 % to 6%. The results indicated that HF-LPME method has an excellent clean-up capacity and a high preconcentration factor and can serve as a simple and sensitive method for monitoring the drug in the urine samples.

  4. Simultaneous Quantitative and Chemical Fingerprint Analysis of Receptaculum Nelumbinis Based on HPLC-DAD-MS Combined with Chemometrics.

    Science.gov (United States)

    Liu, Haitao; Liu, Jiushi; Zhang, Jin; Qi, Yaodong; Jia, Xiaoguang; Zhang, Bengang; Xiao, Peigen

    2016-04-01

    A rapid and sensitive method based on HPLC-DAD-MS was developed for quantitative analysis of two flavonoids and chemical fingerprint analysis to evaluate the quality of Receptaculum Nelumbinis. The analysis was conducted on a Poroshell 120 C18 column (100 × 4.6 mm, 2.7 μm) with 0.2% formic acid buffer solution and methanol as mobile phases with gradient elution. This method displayed good linearity with R(2) at >0.9999 and limits of quantity <0.37 μg mL(-1). Relative standard deviation values for intra- and interday precision were <0.82 and 1.03%, respectively. The mean recovery of hyperoside was 95.54% and of isoquercitrin was 92.10%. Hyperoside and isoquercitrin were determined simultaneously, and 12 peaks in the chemical fingerprint were identified. The chemometric methods, including similarity analysis, hierarchical clustering analysis and principal component analysis, were applied to distinguish 11 batches of Receptaculum Nelumbinis samples. The above results could validate each other and successfully divide these samples into two groups. Moreover, hyperoside and isoquercitrin could be selected as chemical markers to evaluate the quality of Receptaculum Nelumbinis from different localities. This study demonstrated that the developed method was a powerful and beneficial tool to carry out the quality control of Receptaculum Nelumbinis. PMID:26921895

  5. Risks and benefits of combining immunosuppressives and biological agents in inflammatory bowel disease: is the synergy worth the risk?

    OpenAIRE

    Hanauer, Stephen B.

    2007-01-01

    Since the introduction of infliximab to treat Crohn's disease, combination therapy with immunosuppressants has reduced immunogenicity, without impacting efficacy. The availability of novel anti‐TNF agents and potential combined toxicities question the risk/benefit of combination therapies.

  6. Synergistic combinations of antifungals and antivirulence agents to fight against Candida albicans

    DEFF Research Database (Denmark)

    Cui, Jinhui; Ren, Biao; Tong, Yaojun;

    2015-01-01

    -drug resistance, demand innovative strategies for new effective antifungal drugs. Synergistic combinations of antifungals and anti-virulence agents highlight the pragmatic strategy to reduce the development of drug resistant and potentially repurpose known antifungals, which bypass the costly and time......-consuming pipeline of new drug development. Anti-virulence and synergistic combination provide new options for antifungal drug discovery by counteracting the difficulty or failure of traditional therapy for fungal infections....

  7. The Clinical Development of Molecularly Targeted Agents in Combination With Radiation Therapy: A Pharmaceutical Perspective

    International Nuclear Information System (INIS)

    Summary: This paper explores historical and current roles of pharmaceutical industry sponsorship of clinical trials testing radiation therapy combinations with molecularly targeted agents and attempts to identify potential solutions to expediting further combination studies. An analysis of clinical trials involving a combination of radiation therapy and novel cancer therapies was performed. Ongoing and completed trials were identified by searching the (clinicaltrials.gov) Web site, in the first instance, with published trials of drugs of interest identified through American Society of Clinical Oncology, European CanCer Organisation/European Society for Medical Oncology, American Society for Radiation Oncology/European Society for Therapeutic Radiology and Oncology, and PubMed databases and then cross-correlated with (clinicaltrials.gov) protocols. We examined combination trials involving radiation therapy with novel agents and determined their distribution by tumor type, predominant molecular mechanisms examined in combination to date, timing of initiation of trials relative to a novel agent's primary development, and source of sponsorship of such trials. A total of 564 studies of targeted agents in combination with radiation therapy were identified with or without concomitant chemotherapy. Most studies were in phase I/II development, with only 36 trials in phase III. The tumor site most frequently studied was head and neck (26%), followed by non-small cell lung cancer. Pharmaceutical companies were the sponsors of 33% of studies overall and provided support for only 16% of phase III studies. In terms of pharmaceutical sponsorship, Genentech was the most active sponsor of radiation therapy combinations (22%), followed by AstraZeneca (14%). Most radiation therapy combination trials do not appear to be initiated until after drug approval. In phase III studies, the most common (58%) primary endpoint was overall survival. Collectively, this analysis suggests that such

  8. The combination of novel targeted molecular agents and radiation in the treatment of pediatric gliomas

    Directory of Open Access Journals (Sweden)

    Tina eDasgupta

    2013-05-01

    Full Text Available Brain tumors are the most common solid pediatric malignancy. For high-grade, recurrent or refractory pediatric brain tumors, radiation therapy (XRT is an integral treatment modality. In the era of personalized cancer therapy, molecularly targeted agents have been designed to inhibit pathways critical to tumorigenesis. Our evolving knowledge of genetic aberrations in low-grade gliomas is being exploited with targeted inhibitors. These agents are also being combined with XRT to increase their efficacy. In this review, we discuss novel agents targeting three different pathways in low-grade gliomas, and their potential combination with XRT. B-Raf is a kinase in the Ras/Raf/MAPK kinase pathway, which is integral to cellular division, survival and metabolism. In low-grade pediatric gliomas, point mutations in BRAF (BRAF V600E or a BRAF fusion mutation (KIAA1549:BRAF causes overactivation of the MEK/MAPK pathway. Pre-clinical data shows cooperation between XRT and tagrgeted inhibitors of BRAF V600E, and MEK and mTOR inhibitors in the gliomas with the BRAF fusion. A second important signaling cascade in pediatric glioma pathogenesis is the PI3 kinase (PI3K/mTOR pathway. Dual PI3K/mTOR inhibitors are poised to enter studies of pediatric tumors. Finally, many brain tumors express potent stimulators of angiogenesis. Several inhibitors of immunomodulators are currently being evaluated in in clinical trials for the treatment of recurrent or refractory pediatric central nervous system (CNS tumors. In summary, combinations of these targeted inhibitors with radiation are currently under investigation in both translational bench research and early clinical trials. We summarize the molecular rationale for, and the pre-clinical data supporting the combinations of these targeted agents with other anti-cancer agents and XRT in pediatric gliomas. Parallels are drawn to adult gliomas, and the molecular mechanisms underlying the efficacy of these agents is discussed

  9. A clinical trial of oral cholecystography using combinations of contrast agents and two consecutive doses.

    Science.gov (United States)

    Thoeni, R F; Moss, A A

    1982-07-01

    Fifteen healthy volunteers underwent a randomized trial of oral cholecystography (OCG) using 5 different combinations of contrast agents given as 2 consecutive doses: Telepaque (iopanoic acid) given with food (TF) or without food (T), Bilopaque (sodium tyropanoate) given without food, and a combination of both agents (TF-B). The density of gallbladder opacification was judged visually on a scale of 1+ to 4+ and quantitatively by a densitometric method. Comparison of gallbladder opacification on the first and second days of the study revealed 52 of 75 (70%) combinations (TF-T, TF-TF,T-T, TF-B, B-B) resulted in improved opacification, 17% in equal opacification, and 13% in worse opacification on day 2. The TF-B combination showed the highest number (9) of excellent (grade 4+) results and the lowest number (2) of poor (grade 1+ and 2+) results, gave the best opacification in 8 volunteers, and had the highest average density difference (0.32) between first- and second-day opacifications. The TF-TF combination was the next most effective, and the T-T combination was the least effective. The results indicate that OCG in 2 consecutive doses is superior to single-dose OCG, and that a combination of TF-B or TF-TF will provide the greatest gallbladder opacification. The TF-B combination is recommended because of better patient tolerance. PMID:7045975

  10. Derivative Spectrophotometric and HPLC Validated Methods for Simultaneous Determination of Metformin and Glibenclamide in Combined Dosage Form

    Directory of Open Access Journals (Sweden)

    Nabil. A. F. Alhemiarya

    2014-12-01

    Full Text Available The aim of the present Study was to develop a simple and rapid method for determination of metformin (MET and glibenclamide (GLB in Pharmaceutical dosage form. A high-performance liquid chromatographic, fist and second derivative spectrophotometric methods used for the simultaneous determination of MET and GLB. The first derivative amplitudes at 236 nm and 275.7 nm were selected for the assay of MET and GLB, respectively. Calibration curves were established at 5–120 µg/ml for and 1–20 µg/ml, with limits of detection of 0.21µg/ml and 0.29 µg/ml and limits of quantification of 0.64µg/ml and 0.89 µg/mL for MET and GLB, respectively. The second derivative amplitudes at 244.6 nm and 229 nm were selected for the assay of MET and GLB, respectively. Calibration curves were established at 5–120 µg/ml for and 1–20 µg/ml, with limits of detection of 0.46 µg/ml and 0.30 µg/ml and limits of quantification of 0.1.41µg/ml and 0.91 µg/ml for MET and GLB, respectively. In the HPLC method separation was performed by using C18 reversed phase column and a mobile phase of acetonitrile: 0.05 M KH2PO4 (60:40v/v adjusted by phosphoric acid to pH 3, at flow rate of 1 ml/min and the detection wavelength were 210 nm and 238 nm ,the retention time was found to be 3.145 and 7.792 min, linearity over the concentration ranges of 5–75 µm/ml and 2-45 µg/ml, with limits of detection of 0.64 µm/l and 0.02 µg/ml and limits of quantification of 1.95 µg/l and 0.07 µg/mL for MET and GLB, respectively. The methods were also applied for the determination of MET and GLB in the presence of their degradation products formed under variety of stress conditions. Proposed methods were validated for precision, accuracy, linearity range, robustness and ruggedness.

  11. DNA repair in mammalian cells exposed to combinations of carcinogenic agents

    International Nuclear Information System (INIS)

    Cells defective in one or more aspects of repair are killed and often mutagenized more readily than normal cells by DNA damaging agents, and humans whose cells are deficient in repair are at an increased carcinogenic risk compared to normal individuals. The excision repair of uv induced pyrimidine dimers is a well studied system, but the details of the steps in this repair system are far from being understood in human cells. We know that there are a number of chemicals that mimic uv in that normal human cells repair DNA damage from both these agents and from uv by a long patch excision repair system, and that xeroderma pigmentosum cells defective in repair of uv are also defective in the repair of damage from these chemicals. The chemicals we have investigated are AAAF, 4-NQO, DMBA-epoxide, and ICR-170. We describe experiments, using several techniques, in which DNA excision repair is measured after treatment of various human cell strains with combinations of uv and these agents. If two agents have a common rate limiting step then, at doses high enough to saturate the repair system, one would expect the observed repair after a treatment with a combination of agents to be equal to that from one agent alone. Such is not the case for normal human or excision-deficient XP cells. In the former repair is additive and in the latter repair is usually appreciably less than that observed with either agent alone. Models that attempt to explain these surprising results involve complexes of enzymes and cofactors

  12. Antiangiogenic agents in the treatment of recurrent or newly diagnosed glioblastoma: Analysis of single-agent and combined modality approaches

    Directory of Open Access Journals (Sweden)

    Gutin Philip H

    2011-01-01

    Full Text Available Abstract Surgical resection followed by radiotherapy and temozolomide in newly diagnosed glioblastoma can prolong survival, but it is not curative. For patients with disease progression after frontline therapy, there is no standard of care, although further surgery, chemotherapy, and radiotherapy may be used. Antiangiogenic therapies may be appropriate for treating glioblastomas because angiogenesis is critical to tumor growth. In a large, noncomparative phase II trial, bevacizumab was evaluated alone and with irinotecan in patients with recurrent glioblastoma; combination treatment was associated with an estimated 6-month progression-free survival (PFS rate of 50.3%, a median overall survival of 8.9 months, and a response rate of 37.8%. Single-agent bevacizumab also exceeded the predetermined threshold of activity for salvage chemotherapy (6-month PFS rate, 15%, achieving a 6-month PFS rate of 42.6% (p

  13. Combined effect of environmental radiation and other agents: Is there a synergism trap?

    International Nuclear Information System (INIS)

    Most assessments of possible deleterious outcomes from environmental and occupational exposures concentrate on single agents and neglect the potential for combined effects, i.e. synergisms or antagonisms. Biomechanistic considerations based on multistep processes such as carcinogenesis indicate the potential for highly detrimental interactions, if two or more consecutive rate limiting steps are specifically effected by different agents. However, low specificity towards molecular structure or DNA-sequence - and therefore exchangeability - of many genotoxic agents indicate little functional specificity and therefore little vulnerability towards synergism at most occupational and environmental exposure situations. The low potential for significant combined effects for those common low exposure situations where non-genotoxic agents with highly non-linear dose effect relationships and apparent thresholds are involved, is also evident. Nevertheless, a quantitative assessment of the contribution of synergistic interactions to the total detriment from natural and man-made toxicants based on experimental data is far away. The existing database on combined effects is rudimentary, mainly descriptive and rarely covers exposure ranges large enough to make direct inferences to present day low dose exposure situations. In view of the multitude of possible interactions between the large number of potentially harmful agents in the human environment, descriptive approaches will have to be supplemented by the use of mechanistic models for critical health endpoints such as cancer. Finally an important question considering the shape of dose effect relationships for ionizing radiation arises from the unresolved question whether real or apparent thresholds may be used for any genotoxic agent separately or only one time for an exposed genome. (author)

  14. nab-Paclitaxel in combination with biologically targeted agents for early and metastatic breast cancer.

    Science.gov (United States)

    Megerdichian, Christine; Olimpiadi, Yuliya; Hurvitz, Sara A

    2014-06-01

    Taxanes are highly active chemotherapeutic agents used in the treatment of early-stage and metastatic breast cancer. Novel formulations have been developed to improve efficacy and decrease toxicity associated with these cytotoxic agents. nab-Paclitaxel is a biologically interactive, solvent-free, 130-nm-sized albumin-bound paclitaxel, developed to avoid the Cremophor vehicle used in solvent-based paclitaxel. Based on a pivotal phase 3 study, nab-paclitaxel was shown to be safely infused at a significantly higher dose of paclitaxel than the doses used with standard paclitaxel therapy, and had a shorter infusion time, no premedication, and higher response rates. It is now approved in the United States for treatment of breast cancer after failure of combination chemotherapy for metastatic disease or relapse within 6 months of adjuvant therapy, and has demonstrated promising efficacy and favorable tolerability. Recently, several phase 2 and 3 studies have suggested a role for nab-paclitaxel in combination with biologically targeted agents for the treatment of early- and late-stage breast cancer. This review will discuss the findings of clinical trials evaluating nab-paclitaxel in combination with biologically targeted therapeutic agents for breast cancer in the neoadjuvant, adjuvant, and metastatic settings. PMID:24560997

  15. Application of RP-HPLC method in dissolution testing and statistical evaluation by NASSAM for simultaneous estimation of tertiary combined dosages forms

    Institute of Scientific and Technical Information of China (English)

    Yogesh Upadhyay; Nitin Sharma; G.S. Sarma; Ravindra K. Rawal

    2015-01-01

    A dissolution method with robust high performance liquid chromatographic (HPLC) analysis for im-mediate release tablet formulation was developed and validated to meet the requirement as per Inter-national Conference on Harmonization (ICH) and United States Food and Drug Administration (USFDA) guidelines. The method involved the use of Agilent ZORBAX Eclipse XDB C18 column, and temperature was maintained at 30 °C. After optimization, the mobile phase was selected as phosphate buffer (KH2PO4, 30 mM):ACN (60:40, v/v) with pH 3.0, and retention time Rt was found as 3.24, 4.16, and 2.55 min for paracetamol (PCM), chlorpheniramine maleate (CPM) and phenylephrine hydrochloride (PH) respec-tively at 265 nm and at a flow rate of 1 mL/min. The relative standard deviation (%RSD) for 6 replicate measurements was found to be less than 2%. Furthermore net analyte signal standard addition method (NASSAM) with spectrophotometer was performed for standard and liquid oral suspension. On the basis of selectivity, sensitivity and accuracy analysis, it was confirmed that this novel method could be useful for simultaneous estimation of the given drug combinations. Two-way analysis of variance (ANOVA) was applied for evaluating the statistical difference between the assay results obtained via both NASSAM and RP-HPLC methods and ultimately no significant difference was found between both the methods. All the methods and results were acceptable and confirmed that the method was suitable for intended use.

  16. Combination of hollow fiber liquid phase microextraction followed by HPLC-DAD and multivariate curve resolution to determine antibacterial residues in foods of animal origin.

    Science.gov (United States)

    Tajabadi, Fateme; Ghambarian, Mahnaz; Yamini, Yadollah; Yazdanfar, Najmeh

    2016-11-01

    In the present research, a carrier mediated hollow fiber based liquid-phase microextraction approach (HF-LPME) prior to high performance liquid chromatography-diode array detection (HPLC-DAD) was developed for the simultaneous determination of the antibacterial residues of four tetracyclines (TCs) and five quinolones (QNs), which are commonly used as veterinary medicines. In order to obtain high extraction efficiency, the parameters affecting HF-LPME were optimized using a three-factor and three-level Box-Behnken design under response surface methodology. This method was validated according to the recommendations of the Food and Drug Administration (FDA), and, for the first time, successfully applied to a wide range of animal source food samples such as fish, milk, and honey as well as the liver and muscles of lamb and chicken. Analytical performance was determined in terms of linearity, intra- and inter-assay precision, detection and quantification limits, matrix effect, accuracy, and drug stability in real samples. Detection and quantitation limits for the different antibiotics ranged between 0.5-20ngg(-1) and 1.25-40ngg(-1), respectively. Intra and inter-day repeatability, expressed as the relative standard deviation, were in the ranges of 3.4-10.7% and 5.0-11.5%, respectively. The procedure allows good preconcentration factors of 175-700. The results of the validation process proved that the method is suitable for determining TCs and QNs residues in surveillance programs. Finally, the applicability of the proposed method was successfully confirmed by the extraction and determination of nine antibiotics in various animal source food samples. The importance of this methodology relies on the combination of HF-LPME/HPLC-DAD second-order data with multivariate curve resolution-alternative least squares (MCR-ALS) algorithm, which improves the resolution of some overlapped chromatograms and, hence, increases the accuracy and repeatability of drug determination. PMID

  17. Application of RP–HPLC method in dissolution testing and statistical evaluation by NASSAM for simultaneous estimation of tertiary combined dosages forms

    Directory of Open Access Journals (Sweden)

    Yogesh Upadhyay

    2015-10-01

    Full Text Available A dissolution method with robust high performance liquid chromatographic (HPLC analysis for immediate release tablet formulation was developed and validated to meet the requirement as per International Conference on Harmonization (ICH and United States Food and Drug Administration (USFDA guidelines. The method involved the use of Agilent ZORBAX Eclipse XDB C18 column, and temperature was maintained at 30 °C. After optimization, the mobile phase was selected as phosphate buffer (KH2PO4, 30 mM : ACN (60:40, v/v with pH 3.0, and retention time Rt was found as 3.24, 4.16, and 2.55 min for paracetamol (PCM, chlorpheniramine maleate (CPM and phenylephrine hydrochloride (PH respectively at 265 nm and at a flow rate of 1 mL/min. The relative standard deviation (%RSD for 6 replicate measurements was found to be less than 2%. Furthermore net analyte signal standard addition method (NASSAM with spectrophotometer was performed for standard and liquid oral suspension. On the basis of selectivity, sensitivity and accuracy analysis, it was confirmed that this novel method could be useful for simultaneous estimation of the given drug combinations. Two-way analysis of variance (ANOVA was applied for evaluating the statistical difference between the assay results obtained via both NASSAM and RP–HPLC methods and ultimately no significant difference was found between both the methods. All the methods and results were acceptable and confirmed that the method was suitable for intended use.

  18. Coping with antibiotic resistance: combining nanoparticles with antibiotics and other antimicrobial agents.

    Science.gov (United States)

    Allahverdiyev, Adil M; Kon, Kateryna Volodymyrivna; Abamor, Emrah Sefik; Bagirova, Malahat; Rafailovich, Miriam

    2011-11-01

    The worldwide escalation of bacterial resistance to conventional medical antibiotics is a serious concern for modern medicine. High prevalence of multidrug-resistant bacteria among bacteria-based infections decreases effectiveness of current treatments and causes thousands of deaths. New improvements in present methods and novel strategies are urgently needed to cope with this problem. Owing to their antibacterial activities, metallic nanoparticles represent an effective solution for overcoming bacterial resistance. However, metallic nanoparticles are toxic, which causes restrictions in their use. Recent studies have shown that combining nanoparticles with antibiotics not only reduces the toxicity of both agents towards human cells by decreasing the requirement for high dosages but also enhances their bactericidal properties. Combining antibiotics with nanoparticles also restores their ability to destroy bacteria that have acquired resistance to them. Furthermore, nanoparticles tagged with antibiotics have been shown to increase the concentration of antibiotics at the site of bacterium-antibiotic interaction, and to facilitate binding of antibiotics to bacteria. Likewise, combining nanoparticles with antimicrobial peptides and essential oils generates genuine synergy against bacterial resistance. In this article, we aim to summarize recent studies on interactions between nanoparticles and antibiotics, as well as other antibacterial agents to formulate new prospects for future studies. Based on the promising data that demonstrated the synergistic effects of antimicrobial agents with nanoparticles, we believe that this combination is a potential candidate for more research into treatments for antibiotic-resistant bacteria. PMID:22029522

  19. Study of combination treatment effect of the {sup 166}Ho and anticancer agents in-vitro

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, S. M.; Choi, S. J.; Park, K. B. [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    For the development of new controlled drug delivery systems, the application of combination therapy using radioisotopes and tumor static agents has drawn great attention. This study was designed to estimate the treatment effect of the combination therapy with Holmium ({sup 166}Ho) and tumor static agents. Ho-166 was produced at the KAERI using HANARO reactor. The drugs applied were Sunpla, Methotrexate and Doxorubicin. Human glioblastoma (T98G), adenocarcinoma (MKN45), hepatocellular (Hep3B), lung carcinoma (Calu6), ovary adenocarcinoma (NIH:OVCAR- 3) and rat glioma (C6) were used. The cell cytotoxicity on the tumor cell lines determined by MTT assay. In the case where the chemotherapeutic agent was solely applied to the cell lines, the IC{sub 50} values wer e 2.4x10{sup -5}M of the Sunpla for MKN45 and 4.23x10{sup -6}M of the Doxorubicin for Calu6. The radioactivity of Ho-166 occurring 20% apoptosis was 10{mu}Ci. As for Sunpla and Doxorubicin, the value of IC20 was dependent on the cell lines used. The combination treatment of {sup 166}Ho and drug was to improve therapeutic success rate in T98G, MKN45, Hep3B, and Calu6. From this in vitro study it can be concluded that combining 166Ho radionuclide therapy and chemotherapy could enhance the effect of each in eliminating proliferating tumor cells.

  20. Anti static agent characterization in polypropylene by using combined instrumental techniques; Caracterizacao de agente antiestatico em polipropileno atraves de tecnicas instrumentais combinadas

    Energy Technology Data Exchange (ETDEWEB)

    Gibertoni, Eliezer; Monteiro, Marcos R. [Sao Carlos Univ., SP (Brazil). Centro de Caracterizacao e Desenvolvimento de Materiais; Agnelli, Jose Augusto Marcondes [Sao Carlos Univ., SP (Brazil). Dept. de Engenharia de Materiais

    1999-07-01

    Antistatic agents are substances with are added to plastics molding formulations or to the surface of molded articles to minimize the accumulation of static electricity. The analysis and characterization of an antistatic agent in polypropylene using combined techniques provides very specific and detailed information. (author)

  1. Combined effect of levan and cytotoxic agents on the growth of experimental tumours in mice.

    Science.gov (United States)

    Leibovici, J.; Stark, Y.; Wolman, M.

    1983-01-01

    The combined effect of the polysaccharide levan (previously shown to exert a host-dependent as well as direct antitumoural activity) and the cytotoxic agents cyclophosphamide (CY), methotrexate (MTX), vincristine (VINC) and 5-fluoro-uracil (SFU) was studied in Lewis lung carcinoma and AKR lymphoma. Combined chemo- and immunotherapy was applied beginning on the day of tumour cell inoculation. Additive effects were obtained with the combined treatments, compared to single treatments, with all the combinations except MTX-levan in Lewis lung carcinoma, where the combined effect was synergistic. The additive effect was obtained with different doses and routes of chemotherapy, whether local or intraperitoneal. A 2 mg dose of CY combined with levan administered at daily doses of 10 mg, resulted in a 100% prevention of Lewis lung carcinoma growth. It is suggested that the levan may have two beneficial effects: it can exert an inhibitory effect on tumour growth and diminish the deleterious effect of cytotoxic agents on the immune system. PMID:6882675

  2. Optical clearing agent perfusion enhancement via combination of microneedle poration, heating and pneumatic pressure

    OpenAIRE

    Damestani, Y; Melakeberhan, B; Rao, MP; Aguilar, G

    2014-01-01

    Background and Objective Optical clearing agents (OCAs) have shown promise for increasing the penetration depth of biomedical lasers by temporarily decreasing optical scattering within the skin. However, their translation to the clinic has been constrained by lack of practical means for effectively perfusing OCA within target tissues in vivo. The objective of this study was to address this limitation through combination of a variety of techniques to enhance OCA perfusion, including heating of...

  3. Development of an HPLC-UV Method for the Analysis of Drugs Used for Combined Hypertension Therapy in Pharmaceutical Preparations and Human Plasma

    Directory of Open Access Journals (Sweden)

    Serife Evrim Kepekci Tekkeli

    2013-01-01

    Full Text Available A simple, rapid, and selective HPLC-UV method was developed for the determination of antihypertensive drug substances: amlodipine besilat (AML, olmesartan medoxomil (OLM, valsartan (VAL, and hydrochlorothiazide (HCT in pharmaceuticals and plasma. These substances are mostly used as combinations. The combinations are found in various forms, especially in current pharmaceuticals as threesome components: OLM, AML, and HCT (combination I and AML, VAL, and HCT (combination II. The separation was achieved by using an RP-CN column, and acetonitrile-methanol-10 mmol orthophosphoric acid pH 2.5 (7 : 13 : 80, v/v/v was used as a mobile phase; the detector wavelength was set at 235 nm. The linear ranges were found as 0.1–18.5 μg/mL, 0.4–25.6 μg/mL, 0.3–15.5 μg/mL, and 0.3–22 μg/mL for AML, OLM, VAL, and HCT, respectively. In order to check the selectivity of the method for pharmaceutical preparations, forced degradation studies were carried out. According to the validation studies, the developed method was found to be reproducible and accurate as shown by RSD ≤6.1%, 5.7%, 6.9%, and 4.6% and relative mean error (RME ≤10.6%, 5.8%, 6.5%, and 6.8% for AML, OLM, VAL, and HCT, respectively. Consequently, the method was applied to the analysis of tablets and plasma of the patients using drugs including those substances.

  4. Development of an HPLC-UV Method for the Analysis of Drugs Used for Combined Hypertension Therapy in Pharmaceutical Preparations and Human Plasma.

    Science.gov (United States)

    Kepekci Tekkeli, Serife Evrim

    2013-01-01

    A simple, rapid, and selective HPLC-UV method was developed for the determination of antihypertensive drug substances: amlodipine besilat (AML), olmesartan medoxomil (OLM), valsartan (VAL), and hydrochlorothiazide (HCT) in pharmaceuticals and plasma. These substances are mostly used as combinations. The combinations are found in various forms, especially in current pharmaceuticals as threesome components: OLM, AML, and HCT (combination I) and AML, VAL, and HCT (combination II). The separation was achieved by using an RP-CN column, and acetonitrile-methanol-10 mmol orthophosphoric acid pH 2.5 (7 : 13 : 80, v/v/v) was used as a mobile phase; the detector wavelength was set at 235 nm. The linear ranges were found as 0.1-18.5  μ g/mL, 0.4-25.6  μ g/mL, 0.3-15.5  μ g/mL, and 0.3-22  μ g/mL for AML, OLM, VAL, and HCT, respectively. In order to check the selectivity of the method for pharmaceutical preparations, forced degradation studies were carried out. According to the validation studies, the developed method was found to be reproducible and accurate as shown by RSD ≤6.1%, 5.7%, 6.9%, and 4.6% and relative mean error (RME) ≤10.6%, 5.8%, 6.5%, and 6.8% for AML, OLM, VAL, and HCT, respectively. Consequently, the method was applied to the analysis of tablets and plasma of the patients using drugs including those substances. PMID:23634320

  5. Dosage and dose schedule screening of drug combinations in agent-based models reveals hidden synergies

    Directory of Open Access Journals (Sweden)

    Lisa Corina Barros de Andrade e Sousa1

    2016-01-01

    Full Text Available The fungus Candida albicans is the most common causative agent of human fungal infections and better drugs or drug combination strategies are urgently needed. Here, we present an agent-based model of the interplay of C. albicans with the host immune system and with the microflora of the host. We took into account the morphological change of C. albicans from the yeast to hyphae form and its dynamics during infection. The model allowed us to follow the dynamics of fungal growth and morphology, of the immune cells and of microflora in different perturbing situations. We specifically focused on the consequences of microflora reduction following antibiotic treatment. Using the agent-based model, different drug types have been tested for their effectiveness, namely drugs that inhibit cell division and drugs that constrain the yeast-to-hyphae transition. Applied individually, the division drug turned out to successfully decrease hyphae while the transition drug leads to a burst in hyphae after the end of the treatment. To evaluate the effect of different drug combinations, doses, and schedules, we introduced a measure for the return to a healthy state, the infection score. Using this measure, we found that the addition of a transition drug to a division drug treatment can improve the treatment reliability while minimizing treatment duration and drug dosage. In this work we present a theoretical study. Although our model has not been calibrated to quantitative experimental data, the technique of computationally identifying synergistic treatment combinations in an agent based model exemplifies the importance of computational techniques in translational research.

  6. Determination of abamectin in citrus fruits using SPE combined with dispersive liquid-liquid microextraction and HPLC-UV detection.

    Science.gov (United States)

    Rezaee, Mohammad; Mashayekhi, Hossein Ali; Saleh, Abolfazl; Abdollahzadeh, Yaser; Naeeni, Mohammad Hosein; Fattahi, Nazir

    2013-08-01

    A new pretreatment method, SPE combined with dispersive liquid-liquid microextraction, was proposed for the determination of abamectin in citrus fruit samples for the first time. In this method, fruit samples were extracted by ultrasound-assisted extraction followed by SPE. Then, the SPE was used as a disperser solvent in the next dispersive liquid-liquid microextraction step for further purification and enrichment of abamectin. The effects of various parameters on the extraction efficiency of the proposed method were investigated and optimized. Good linearity of abamectin was obtained from 0.005 to 10.0 mg/kg for B1a and from 0.05 to 10.0 mg/kg for B1b with correlation coefficient (r(2)) of 0.998 for B1a and 0.991 for B1b, respectively. The LODs were 0.001 and 0.008 mg/kg (S/N = 3) for B1a and B1b, respectively. The relative recoveries at three spiked levels were ranged from 87 to 96% with the RSD less than 11% (n = 3). The method has been successfully applied to the determination of abamectin in citrus fruit samples. PMID:23913592

  7. Expressions for multilinear combined pH/organic solvent elution of ionizable analytes in reversed-phase HPLC.

    Science.gov (United States)

    Zisi, Ch; Fasoula, S; Pappa-Louisi, A; Nikitas, P

    2013-10-15

    Expressions for the retention time of ionogenic analytes eluted under multilinear double pH/solvent-gradients in reversed-phase liquid chromatography are developed by dividing each gradient profile into a finite number of subportions, where the solute retention factors or their logarithms vary linearly with time. To test the theory, two series of experimental gradient retention data of amino acid OPA derivatives were analyzed: The first one was a monolinear or bilinear pH-gradient data set obtained in eluents with different but constant organic modifier contents, whereas the second data set comprised retention data of combined pH/organic solvent-gradients, where the organic content was changed linearly with time but the variation of pH exhibited a curved form approximated by five linear subportions. It was found that the derived expressions describe these experimental retention data with high accuracy, since under double pH/solvent-gradients the overall errors in the fitted and predicted retention times were 1.9% and 1.7%, respectively, whereas under simple pH-gradients these errors were 0.9% and 2%, respectively. PMID:24010983

  8. Antimicrobial agents: their combined effects on total protein content of the endoparasitoid Pimpla turionellae L. (Hymenoptera: Ichneumonidae)

    OpenAIRE

    Büyükgüzel, Kemal

    2002-01-01

    The effects of some antibiotics and antifungal agents in combination on the total protein content of young pupae of the hymenopterous endoparasitoid, Pimpla turionellae L., were investigated by rearing the larvae aseptically on chemically defined synthetic diets. These effects varied with the kinds and levels of the combination of antimicrobial agents in the diets. The combinations of antibiotics generally increased the total protein content according to their individual levels in the diets. ...

  9. Treatment of Aluminium Phosphide Poisoning with a Combination of Intravenous Glucagon, Digoxin and Antioxidant Agents

    Directory of Open Access Journals (Sweden)

    Zohreh Oghabian

    2016-08-01

    Full Text Available Aluminium phosphide (AlP is used to protect stored grains from rodents. It produces phosphine gas (PH3, a mitochondrial poison thought to cause toxicity by blocking the cytochrome c oxidase enzyme and inhibiting oxidative phosphorylation, which results in cell death. AlP poisoning has a high mortality rate among humans due to the rapid onset of cardiogenic shock and metabolic acidosis, despite aggressive treatment. We report a 21-yearold male who was referred to the Afzalipour Hospital, Kerman, Iran, in 2015 after having intentionally ingested a 3 g AlP tablet. He was successfully treated with crystalloid fluids, vasopressors, sodium bicarbonate, digoxin, glucagon and antioxidant agents and was discharged from the hospital six days after admission in good clinical condition. For the treatment of AlP poisoning, the combination of glucagon and digoxin with antioxidant agents should be considered. However, evaluation of further cases is necessary to optimise treatment protocols.

  10. Treatment of Aluminium Phosphide Poisoning with a Combination of Intravenous Glucagon, Digoxin and Antioxidant Agents.

    Science.gov (United States)

    Oghabian, Zohreh; Mehrpour, Omid

    2016-08-01

    Aluminium phosphide (AlP) is used to protect stored grains from rodents. It produces phosphine gas (PH3), a mitochondrial poison thought to cause toxicity by blocking the cytochrome c oxidase enzyme and inhibiting oxidative phosphorylation, which results in cell death. AlP poisoning has a high mortality rate among humans due to the rapid onset of cardiogenic shock and metabolic acidosis, despite aggressive treatment. We report a 21-year-old male who was referred to the Afzalipour Hospital, Kerman, Iran, in 2015 after having intentionally ingested a 3 g AlP tablet. He was successfully treated with crystalloid fluids, vasopressors, sodium bicarbonate, digoxin, glucagon and antioxidant agents and was discharged from the hospital six days after admission in good clinical condition. For the treatment of AlP poisoning, the combination of glucagon and digoxin with antioxidant agents should be considered. However, evaluation of further cases is necessary to optimise treatment protocols. PMID:27606117

  11. Preclinical Investigations of PM01183 (Lurbinectedin) as a Single Agent or in Combination with Other Anticancer Agents for Clear Cell Carcinoma of the Ovary

    Science.gov (United States)

    Takahashi, Ryoko; Mabuchi, Seiji; Kawano, Mahiru; Sasano, Tomoyuki; Matsumoto, Yuri; Kuroda, Hiromasa; Kozasa, Katsumi; Hashimoto, Kae; Sawada, Kenjiro; Kimura, Tadashi

    2016-01-01

    Objective The objective of this study was to evaluate the antitumor effects of lurbinectedin as a single agent or in combination with existing anticancer agents for clear cell carcinoma (CCC) of the ovary, which is regarded as an aggressive, chemoresistant, histological subtype. Methods Using human ovarian CCC cell lines, the antitumor effects of lurbinectedin, SN-38, doxorubicin, cisplatin, and paclitaxel as single agents were assessed using the MTS assay. Then, the antitumor effects of combination therapies involving lurbinectedin and 1 of the other 4 agents were evaluated using isobologram analysis to examine whether these combinations displayed synergistic effects. The antitumor activity of each treatment was also examined using cisplatin-resistant and paclitaxel-resistant CCC sublines. Finally, we determined the effects of mTORC1 inhibition on the antitumor activity of lurbinectedin-based chemotherapy. Results Lurbinectedin exhibited significant antitumor activity toward chemosensitive and chemoresistant CCC cells in vitro. An examination of mouse CCC cell xenografts revealed that lurbinectedin significantly inhibits tumor growth. Among the tested combinations, lurbinectedin plus SN-38 resulted in a significant synergistic effect. This combination also had strong synergistic effects on both the cisplatin-resistant and paclitaxel-resistant CCC cell lines. Everolimus significantly enhanced the antitumor activity of lurbinectedin-based chemotherapies. Conclusions Lurbinectedin, a new agent that targets active transcription, exhibits antitumor activity in CCC when used as a single agent and has synergistic antitumor effects when combined with irinotecan. Our results indicate that lurbinectedin is a promising agent for treating ovarian CCC, both as a first-line treatment and as a salvage treatment for recurrent lesions that develop after platinum-based or paclitaxel treatment. PMID:26986199

  12. Suspension culture combined with chemotherapeutic agents for sorting of breast cancer stem cells

    International Nuclear Information System (INIS)

    Cancer stem cell (CSC) hypothesis has not been well demonstrated by the lack of the most convincing evidence concerning a single cell capable of giving rise to a tumor. The scarcity in quantity and improper approaches for isolation and purification of CSCs have become the major obstacles for great development in CSCs. Here we adopted suspension culture combined with anticancer regimens as a strategy for screening breast cancer stem cells (BrCSCs). BrCSCs could survive and be highly enriched in non-adherent suspension culture while chemotherapeutic agents could destroy most rapidly dividing cancer cells and spare relatively quiescent BrCSCs. TM40D murine breast cancer cells were cultured in serum-free medium. The expression of CD44+CD24- was measured by flow cytometry. Cells of passage 10 were treated in combination with anticancer agents pacilitaxel and epirubicin at different peak plasma concentrations for 24 hours, and then maintained under suspension culture. The rate of apoptosis was examined by flow cytometry with Annexin-V fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining method. Selected cells in different amounts were injected subcutaneously into BALB/C mice to observe tumor formation. Cells of passage 10 in suspension culture had the highest percentage of CD44+CD24- (about 77 percent). A single tumor cell in 0.35 PPC could generate tumors in 3 of 20 BALB/C mice. Suspension culture combined with anticancer regimens provides an effective means of isolating, culturing and purifying BrCSCs

  13. Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents

    OpenAIRE

    Daniel Matatagui; José Luis Fontecha; María Jesús Fernández; Isabel Gràcia; Carles Cané; José Pedro Santos; María Carmen Horrillo

    2014-01-01

    The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentr...

  14. Biological effects of radiation in combination with other physical, chemical or biological agents. Annex L

    International Nuclear Information System (INIS)

    This Annex considers the combined action of radiation with potentially important environmental conditions. Since there is a scarcity of systematic data on which an analysis of combined effects can be based, this Annex will be more hypothetical and will attempt to suggest definitions, to identify suitable methods of analysis, to select from a large amount of diffuse information the conditions and the data of importance for further consideration and to provide suggestions for future research. For humans in environmental circumstances the UNSCEAR Committee has been unable to document any clear case of synergistic interaction between radiation and other agents, which could lead to substantial modifications of the risk estimates for significant sections of the population

  15. Combination therapy for advanced thyroid cancer with immunochemotherapeutic agents and Co60 irradiation

    International Nuclear Information System (INIS)

    In this clinical study OK-432 and/or PSK and BCG preparation were used for potentiation of cell-mediated immunity, Mitomycin and/or Bleomycin and Carboquone for carcinostatic chemotherapeutics. Local and systemic administration of these agents and Co60 irradiation were applied in various combination for 5 patients with advanced thyroid papillary adeno-carcinoma. All patients except one showed remarkable reduction in the tumor size. The tumor reduction continued a variety of period from several months to years. In a 69-year-old woman her huge neck tumor necrotized and disappeared without any paticular untoward effects, and she is in complete remission at least for 2 years. The principal effect of OK-432 appeared to be on increase of cell-mediated immunity. The data suggests that OK-432 may be useful in combination with conventional carcinostatic chemotherapeutics and/or radiation. (author)

  16. Biogenic Amines in Salted Duck Analyzed by TLC Combined with HPLC%TLC和HPLC法相结合分析盐水鸭中的生物胺

    Institute of Scientific and Technical Information of China (English)

    王凤芹; 刘芳; 孟勇; 王道营; 诸永志; 徐为民

    2011-01-01

    The composition and contents of biogenic amines in salted duck were analyzed by thin layer chromatography (TLC) combined with high performance liquid chromatography (HPLC). Six biogenic amines including putrescine, cadaverine, spermidine, spermine, tyramine and 2-phenylethylamine were detected in salted duck samples by TLC. Similarly, six biogenic amines were also detected by HPLC, and the concentration of each biogenic amine was less than 204 ~t g/g. The analytical results obtained by both methods were consistent. Therefore, TLC can be used as an economic and rapid method for the qualitative analysis of biogenic amines in meat products.%应用薄层层析(TLC)和高效液相色谱(HPLC)两种方法分析盐水鸭中生物胺的组成及含量。薄层层析结果显示,盐水鸭样品中存在着腐胺、尸胺、亚精胺、精胺、酪胺和2.苯乙胺;利用高效液相色谱法也检测到了以上6种生物胺,且各生物胺的含量均在204μg/g以下。两种方法结果相吻合,TLC法可以作为肉制品中生物胺定性分析的一种经济便捷的方法。

  17. Combining Bayesian Networks and Agent Based Modeling to develop a decision-support model in Vietnam

    Science.gov (United States)

    Nong, Bao Anh; Ertsen, Maurits; Schoups, Gerrit

    2016-04-01

    Complexity and uncertainty in natural resources management have been focus themes in recent years. Within these debates, with the aim to define an approach feasible for water management practice, we are developing an integrated conceptual modeling framework for simulating decision-making processes of citizens, in our case in the Day river area, Vietnam. The model combines Bayesian Networks (BNs) and Agent-Based Modeling (ABM). BNs are able to combine both qualitative data from consultants / experts / stakeholders, and quantitative data from observations on different phenomena or outcomes from other models. Further strengths of BNs are that the relationship between variables in the system is presented in a graphical interface, and that components of uncertainty are explicitly related to their probabilistic dependencies. A disadvantage is that BNs cannot easily identify the feedback of agents in the system once changes appear. Hence, ABM was adopted to represent the reaction among stakeholders under changes. The modeling framework is developed as an attempt to gain better understanding about citizen's behavior and factors influencing their decisions in order to reduce uncertainty in the implementation of water management policy.

  18. Effect of combination of extracts of ginseng and ginkgo biloba on acetylcholine in amyloid beta-protein-treated rats determined by an improved HPLC

    Institute of Scientific and Technical Information of China (English)

    Jian-xun LIU; Wei-hong CONG; Li XU; Jian-nong WANG

    2004-01-01

    AIM: To determine the concentration of acetylcholine (ACh) in amyloid beta-protein (Aβ) treated rats and offer a method determining ACh as well. METHODS: A 1-month combination of extrats of ginseng and ginkgo biloba(Naoweikang) ig administration to rats was performed daily after bilateral injection of Aβ1-40 (4 g/L, 1 μL for each side) into hippocampus. After decollation, homogenizing, and centrifuging and extracting, a high pressure liquid chromatographic (HPLC) method using electrochemical detection (ECD) combined with two immobilized enzyme reactors was used to determine ACh in rat whole brain. RESULTS: With a mobile phase consisting of disodium hydrogen orthophosphate, tetramethylammonium chloride (TMAC1), octanesulfonic acid sodium salt (OSA) and"Reagent MB" at a final pH of 8.0, ACh was determined while removing the interfering choline in less than 10 min at a flow rate of 0.35 mL/min on a platinum (Pt) working electrode at a potential of +300 mV vs a solid-state palladium (Pd) reference electrode. Linear regression analysis of peak area vs concentration demonstrated linearity in the 28.01 to 1400.06 μg/L injection range. The r-value was 0.9978. The limit of detection (LOD) is 0.28 ng on column. ACh in whole brain decreased by 20.34 % (from 162.1±32.7 to 134.7±14.0 μg/L, P<0.05) after bilateral injection of Aβ into rat hippocampus. After Naoweikang administration (31 and 15.5 mg/kg, respectively), ACh increased by 19.97 % (from 134.7+14.0 to 161.6+26.2 μg/L, P<0.05) and 18.56 % (from 134.7+14.0 to 159.7+22.9 μg/L, P<0.05), respectively. CONCLUSION: Naoweikang significantly increased the level of ACh in whole brain of Aβ treated rats. And a sensitive, selective and reliable method for routinely determining ACh in rat whole brain was established in this study.

  19. Abiotic reductive extraction of arsenic from contaminated soils enhanced by complexation: Arsenic extraction by reducing agents and combination of reducing and chelating agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Jung [Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Lee, Jae-Cheol [Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Baek, Kitae, E-mail: kbaek@jbnu.ac.kr [Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of)

    2015-02-11

    Highlights: • Abiotic reductive extraction of As from contaminated soils was studied. • Oxalate/ascorbate were effective in extracting As bound to amorphous iron oxides. • Reducing agents were not effective in extracting As bound to crystalline oxides. • Reductive As extraction was greatly enhanced by complexation. • Combination of dithionite and EDTA could extract about 90% of the total As. - Abstract: Abiotic reductive extraction of arsenic from contaminated soils was studied with various reducing agents and combinations of reducing and chelating agents in order to remediate arsenic-contaminated soils. Oxalate and ascorbic acid were effective to extract arsenic from soil in which arsenic was associated with amorphous iron oxides, but they were not effective to extract arsenic from soils in which arsenic was bound to crystalline oxides or those in which arsenic was mainly present as a scorodite phase. An X-ray photoelectron spectroscopy study showed that iron oxides present in soils were transformed to Fe(II,III) or Fe(II) oxide forms such as magnetite (Fe{sub 3}O{sub 4}, Fe{sup II}Fe{sub 2}{sup III}O{sub 4}) by reduction with dithionite. Thus, arsenic extraction by dithionite was not effective due to the re-adsorption of arsenic to the newly formed iron oxide phase. Combination of chelating agents with reducing agents greatly improved arsenic extraction from soil samples. About 90% of the total arsenic could be extracted from all soil samples by using a combination of dithionite and EDTA. Chelating agents form strong complexation with iron, which can prevent precipitation of a new iron oxide phase and also enhance iron oxide dissolution via a non-reductive dissolution pathway.

  20. Combining antihypertensive and antihyperlipidemic agents – optimizing cardiovascular risk factor management

    Directory of Open Access Journals (Sweden)

    Zamorano J

    2011-11-01

    Full Text Available José Zamorano1, Jonathan Edwards21Hospital Clinico San Carlos, Madrid, Spain; 2UBC Scientific Solutions, 5 North Street, Horsham, West Sussex, UKAbstract: Clinical guidelines now recognize the importance of a multifactorial approach to managing cardiovascular (CV risk. This idea was taken a step further with the concept of the Polypill™. There are, however, considerable patent, pharmacokinetic, pharmacodynamic, registration, and cost implications that will need to be overcome before the Polypill™ or other single-pill combinations of CV medications become widely available. However, a medication targeting blood pressure (BP and lipids provides much of the proposed benefits of the Polypill™. A single-pill combination of the antihypertensive amlodipine besylate and the lipid-lowering medication atorvastatin calcium (SPAA is currently available in many parts of the world. This review describes the rationale for this combination therapy and the clinical trials that have demonstrated that these two agents can be combined without the loss of efficacy for either agent or an increase in the incidence of adverse events. The recently completed Cluster Randomized Usual Care vs Caduet Investigation Assessing Long-term-risk (CRUCIAL trial is discussed in detail. CRUCIAL was a 12-month, international, multicenter, prospective, open-label, parallel design, cluster-randomized trial, which demonstrated that a proactive intervention strategy based on SPAA in addition to usual care (UC had substantial benefits on estimated CV risk, BP, and lipids over continued UC alone. Adherence with antihypertensive and lipid-lowering therapies outside of the controlled environment of clinical trials is very low (~30%–40% at 12 months. Observational studies have demonstrated that improving adherence to lipid-lowering and antihypertensive medications may reduce CV events. One means of improving adherence is the use of single-pill combinations. Real-world observational

  1. Antigonadotropic progestogens as contraceptive agents in women with contraindication to combined pill.

    Science.gov (United States)

    Maitrot-Mantelet, Lorraine; Agopian, Anahid; Gompel, Anne

    2010-12-01

    Synthetic progestogens belong to different pharmacological classes and are mixed steroids. They display different properties due to their various affinities to the different steroid receptors. In addition, the dosage used can modify their side effects. Normethyltestosterone used at minimal doses, also called progestogen only pill (POP), constitute the standard recommended hormonal contraception for women with vascular and metabolic contraindications to combined pill (COC). However, POP efficacy and gynecological tolerance are limited. We have developed for more than 20 years in France the use of two pregnane derivatives as contraceptive agents in women with contraindication to COC. Chlormadinone acetate and cyproterone acetate have different antigonadotropic potencies but remain neutral on vascular risk. We have analyzed the efficacy, vascular and gynecological tolerances in 187 women with systemic lupus erythematous with or without antiphospholipids. Venous thrombosis and arterial events rates were lower than those reported in the literature. The current experience in women with thrombophilia is similar as reported in a series of 150 patients. In addition, we have also used antigonadotropic progestins in women with hereditary angioedema (HAE) types I, II or III. HAE symptoms can be induced or worsened by COC. We could demonstrate a significant improvement of the symptoms in most women with HAE under antigonadotropic progestins. Gynecological and general tolerances were satisfactory. In conclusion, antigonadotropic progestins could have clinical positive benefits as contraceptive agents in women with contraindication to COC. PMID:25961217

  2. Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents

    Science.gov (United States)

    Matatagui, Daniel; Fontecha, José Luis; Fernández, María Jesús; Gràcia, Isabel; Cané, Carles; Santos, José Pedro; Horrillo, María Carmen

    2014-01-01

    The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved. PMID:25029282

  3. Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    Daniel Matatagui

    2014-07-01

    Full Text Available The following paper examines a time-efficient method for detecting biological warfare agents (BWAs. The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13, and the rabbit immunoglobulin (Rabbit IgG has been detected using the polyclonal antibody goat anti-rabbit (GAR. Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved.

  4. Love-wave sensors combined with microfluidics for fast detection of biological warfare agents.

    Science.gov (United States)

    Matatagui, Daniel; Fontecha, José Luis; Fernández, María Jesús; Gràcia, Isabel; Cané, Carles; Santos, José Pedro; Horrillo, María Carmen

    2014-01-01

    The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved. PMID:25029282

  5. Combined use of HPLC-ICP-MS and microwave-assisted extraction for the determination of cobalt compounds in nutritive supplements.

    Science.gov (United States)

    Yang, Fang-Yu; Jiang, Shiuh-Jen; Sahayam, A C

    2014-03-15

    Speciation analysis of cobalt in nutritive supplements has been carried out using HPLC and ICP-MS equipped with a membrane desolvation sample introduction system as detector. In this study, cobalt containing compounds, namely Co(II), cyanocobalamin (CN-Cbl) and hydroxylcobalamin (OH-Cbl), were well separated by reversed phase HPLC with a C8-HPLC column as the stationary phase and 8 mmol L(-1) ammonium acetate in 22%v/v methanol solution (pH 4) as the mobile phase using isocratic elution. Detection limit was in the range of 0.008-0.014 μg CoL(-1) for various Co species. Over 98% of the total cobalt species was extracted in nutritive supplements using a 0.5%v/v HNO3 solution in a microwave field; and the spike recovery was in the range of 92-108% for various species. The HPLC-ICP-MS results showed a satisfactory agreement with the total cobalt concentrations obtained by ICP-MS analysis of completely dissolved samples. PMID:24206708

  6. Synergy Testing of Vancomycin-Resistant Enterococcus faecium against Quinupristin-Dalfopristin in Combination with Other Antimicrobial Agents

    OpenAIRE

    Matsumura, S O; Louie, L; Louie, M.; Simor, A E

    1999-01-01

    Using checkerboard and time-kill assays, we evaluated the in vitro activity of quinupristin-dalfopristin (RP 59500) alone and in combination with five other antimicrobial agents against 12 clinical strains of vancomycin-resistant Enterococcus faecium (VREF). In time-kill studies, six VREF strains exhibited synergism with the combination of quinupristin-dalfopristin and doxycycline and three exhibited synergism with quinupristin-dalfopristin plus ampicillin-sulbactam. Combinations of quinupris...

  7. Assessing the Risk of Birth Defects Associated with Exposure to Fixed-Dose Combined Antituberculous Agents during Pregnancy in Rats

    OpenAIRE

    O Awodele; E. B. Patrick; Esther Oluwatoyin Agbaje; Oremosu, A. A.; Gbotolorun, S. C.

    2012-01-01

    Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investig...

  8. Assessing the Risk of Birth Defects Associated with Exposure to Fixed-Dose Combined Antituberculous Agents during Pregnancy in Rats

    Directory of Open Access Journals (Sweden)

    O. Awodele

    2012-01-01

    Full Text Available Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investigate the possible roles of vitamin C in modulating the teratogenic effects of these agents on the fetus using animal model. Pregnant rats were divided into 3 groups with 12 animals per group: group 1 received distilled water (10 mL/kg orally; group 2 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents orally; group 3 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents plus vitamin C (10 mg/kg/day orally. Six rats in each group were randomly selected and sacrificed on day 20 by cervical dislocation prior to day 21 of gestation, and the foetuses were harvested through abdominal incision for physical examination. Blood samples were collected from the 1st filial rats of the remaining six animals for biochemical and hematological examination. The liver, kidney, heart, and brain of all the sacrificed animals were used for histopathological examination. There were significant (≤0.05 low birth weights of the foetuses of the animals that were treated with fixed-dose combined antituberculous agents. The haematological parameters also revealed a reduction in the platelets counts and neutrophiles at the first filial generation. Significant (≤0.05 elevations in the levels of aspartate aminotransferase (AST and alkaline phosphatase (ALP in the foetuses of the animals treated with fixed-dose combined antituberculous agents were also observed. However, the combination of vitamin C with fixed-dose combined antituberculous agents

  9. Assessing the risk of birth defects associated with exposure to fixed-dose combined antituberculous agents during pregnancy in rats.

    Science.gov (United States)

    Awodele, O; Patrick, E B; Oluwatoyin Agbaje, Esther; Oremosu, A A; Gbotolorun, S C

    2012-01-01

    Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investigate the possible roles of vitamin C in modulating the teratogenic effects of these agents on the fetus using animal model. Pregnant rats were divided into 3 groups with 12 animals per group: group 1 received distilled water (10 mL/kg) orally; group 2 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents orally; group 3 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents plus vitamin C (10 mg/kg/day) orally. Six rats in each group were randomly selected and sacrificed on day 20 by cervical dislocation prior to day 21 of gestation, and the foetuses were harvested through abdominal incision for physical examination. Blood samples were collected from the 1st filial rats of the remaining six animals for biochemical and hematological examination. The liver, kidney, heart, and brain of all the sacrificed animals were used for histopathological examination. There were significant (P ≤ 0.05) low birth weights of the foetuses of the animals that were treated with fixed-dose combined antituberculous agents. The haematological parameters also revealed a reduction in the platelets counts and neutrophiles at the first filial generation. Significant (P ≤ 0.05) elevations in the levels of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the foetuses of the animals treated with fixed-dose combined antituberculous agents were also observed. However, the combination of vitamin C with fixed-dose combined antituberculous agents significantly

  10. A Novel validated stability indicating Chromatographic method for the Simultaneous estimation of Levocetrizine and Montelukast in the combined dosage form by RP-HPLC

    OpenAIRE

    Kommana Bala Ram Kumar, Girija Sastry.V, G.Komala, Preethi Priyadarshini, P. Naresh; Kommana Bala Ram Kumar

    2013-01-01

    The objective of the current study was to develop and validate a rapid, precise, specific reverse phase HPLC for the quantitative determination of Levocetrizine and Montelukast in its dosage form. The determination is done for the active pharmaceutical ingredient in its pharmaceutical dosage form. The dosage was subjected to analytical studies as per international conference on harmonization (ICH) prescribed. It was found Levocetrizine and Montelukast is very sensitive to different conditions...

  11. Growth-inhibitory effects of the chemopreventive agent indole-3-carbinol are increased in combination with the polyamine putrescine in the SW480 colon tumour cell line

    Directory of Open Access Journals (Sweden)

    Gescher Andreas

    2003-01-01

    Full Text Available Abstract Background Many tumours undergo disregulation of polyamine homeostasis and upregulation of ornithine decarboxylase (ODC activity, which can promote carcinogenesis. In animal models of colon carcinogenesis, inhibition of ODC activity by difluoromethylornithine (DFMO has been shown to reduce the number and size of colon adenomas and carcinomas. Indole-3-carbinol (I3C has shown promising chemopreventive activity against a range of human tumour cell types, but little is known about the effect of this agent on colon cell lines. Here, we investigated whether inhibition of ODC by I3C could contribute to a chemopreventive effect in colon cell lines. Methods Cell cycle progression and induction of apoptosis were assessed by flow cytometry. Ornithine decarboxylase activity was determined by liberation of CO2 from 14C-labelled substrate, and polyamine levels were measured by HPLC. Results I3C inhibited proliferation of the human colon tumour cell lines HT29 and SW480, and of the normal tissue-derived HCEC line, and at higher concentrations induced apoptosis in SW480 cells. The agent also caused a decrease in ODC activity in a dose-dependent manner. While administration of exogenous putrescine reversed the growth-inhibitory effect of DFMO, it did not reverse the growth-inhibition following an I3C treatment, and in the case of the SW480 cell line, the effect was actually enhanced. In this cell line, combination treatment caused a slight increase in the proportion of cells in the G2/M phase of the cell cycle, and increased the proportion of cells undergoing necrosis, but did not predispose cells to apoptosis. Indole-3-carbinol also caused an increase in intracellular spermine levels, which was not modulated by putrescine co-administration. Conclusion While indole-3-carbinol decreased ornithine decarboxylase activity in the colon cell lines, it appears unlikely that this constitutes a major mechanism by which the agent exerts its antiproliferative

  12. Activation of the human immune system by chemotherapeutic or targeted agents combined with the oncolytic parvovirus H-1

    International Nuclear Information System (INIS)

    Parvovirus H-1 (H-1PV) infects and lyses human tumor cells including melanoma, hepatoma, gastric, colorectal, cervix and pancreatic cancers. We assessed whether the beneficial effects of chemotherapeutic agents or targeted agents could be combined with the oncolytic and immunostimmulatory properties of H-1PV. Using human ex vivo models we evaluated the biological and immunological effects of H-1PV-induced tumor cell lysis alone or in combination with chemotherapeutic or targeted agents in human melanoma cells +/- characterized human cytotoxic T-cells (CTL) and HLA-A2-restricted dendritic cells (DC). H-1PV-infected MZ7-Mel cells showed a clear reduction in cell viability of >50%, which appeared to occur primarily through apoptosis. This correlated with viral NS1 expression levels and was enhanced by combination with chemotherapeutic agents or sunitinib. Tumor cell preparations were phagocytosed by DC whose maturation was measured according to the treatment administered. Immature DC incubated with H-1PV-induced MZ7-Mel lysates significantly increased DC maturation compared with non-infected or necrotic MZ7-Mel cells. Tumor necrosis factor-α and interleukin-6 release was clearly increased by DC incubated with H-1PV-induced SK29-Mel tumor cell lysates (TCL) and was also high with DC-CTL co-cultures incubated with H-1PV-induced TCL. Similarly, DC co-cultures with TCL incubated with H-1PV combined with cytotoxic agents or sunitinib enhanced DC maturation to a greater extent than cytotoxic agents or sunitinib alone. Again, these combinations increased pro-inflammatory responses in DC-CTL co-cultures compared with chemotherapy or sunitinib alone. In our human models, chemotherapeutic or targeted agents did not only interfere with the pronounced immunomodulatory properties of H-1PV, but also reinforced drug-induced tumor cell killing. H-1PV combined with cisplatin, vincristine or sunitinib induced effective immunostimulation via a pronounced DC maturation, better cytokine

  13. Analysis of 21% Pymetrozine · Etofenprox Suspending Agent by HPLC Method%21%吡蚜酮·醚菊酯悬浮剂的高效液相色谱分析

    Institute of Scientific and Technical Information of China (English)

    赵来成; 王莉莉; 束兆林; 庄桂花; 吉沐祥; 费子华

    2012-01-01

    The quantitative analysis of Pymetrozine and Etofenprox in 21% Pymetrozine·Etofenprox suspending agent by HPLC was conducted here. The results showed that it was a good method with high precision and accuracy. The variation coefficient ranged from 0.085% to 0.094% , and the average recovery ranged from 100.1% to 101.2%.%采用反相高效液相色谱法对21%吡蚜酮·醚菊酯悬浮剂中吡蚜酮和醚菊酯的质量分数进行了定量测定.结果表明,该方法具有较高的精密度和准确度,其重复测定结果的变异系数为0.085%~0.094%,平均回收率为100.1% ~101.2%.

  14. How Do Place and Objects Combine? "What-Where" Memory for Human-Like Agents

    Czech Academy of Sciences Publication Activity Database

    Brom, C.; Korenko, T.; Lukavský, Jiří

    Berlín: Springer, 2009, s. 42-48. (Intelligent Virtual Agents. 5773). ISBN 978-3-642-04379-6. [International Conference: Intelligent Virtual Agents 2009 /9./. Amsterodam (NL), 14.09.2009-16.09.2009] R&D Projects: GA AV ČR 1ET100300517 Institutional research plan: CEZ:AV0Z70250504 Keywords : episodic memory * intelligent virtual agents * memory model Subject RIV: AN - Psychology

  15. Combination chemotherapy versus single-agent therapy as first- and second-line treatment in metastatic breast cancer

    DEFF Research Database (Denmark)

    Joensuu, H; Holli, K; Heikkinen, M;

    1998-01-01

    -line treatments were compared or when survival was calculated from the beginning of the second-line therapy. CONCLUSION: Patients treated with single-agent E followed by single-agent M had similar survival, but less treatment-related toxicity and better QOL as compared with those treated with CEF followed by MV.......PURPOSE: We report results of a randomized prospective study that compared single agents of low toxicity given both as the first-line and second-line chemotherapy with combination chemotherapy in advanced breast cancer with distant metastases. PATIENTS AND METHODS: Patients in the single-agent arm...... younger than 50. RESULTS: An objective response (complete [CR] or partial [PR]) was obtained in 55%, 48%, 16%, and 7% of patients treated with CEF, E, M, and MV, respectively. A response to CEF tended to last longer than a response to E (median, 12 v 10.5 months; P = .07). Treatment-related toxicity was...

  16. Multi-step infrared macro-fingerprint features of ethanol extracts from different Cistanche species in China combined with HPLC fingerprint

    Science.gov (United States)

    Xu, Rong; Sun, Suqin; Zhu, Weicheng; Xu, Changhua; Liu, Yougang; Shen, Liang; Shi, Yue; Chen, Jun

    2014-07-01

    The genus Cistanche generally has four species in China, including C. deserticola (CD), C. tubulosa (CT), C. salsa (CS) and C. sinensis (CSN), among which CD and CT are official herbal sources of Cistanche Herba (CH). To clarify the sources of CH and ensure the clinical efficacy and safety, a multi-step IR macro-fingerprint method was developed to analyze and evaluate the ethanol extracts of the four species. Through this method, the four species were distinctively distinguished, and the main active components phenylethanoid glycosides (PhGs) were estimated rapidly according to the fingerprint features in the original IR spectra, second derivative spectra, correlation coefficients and 2D-IR correlation spectra. The exclusive IR fingerprints in the spectra including the positions, shapes and numbers of peaks indicated that constitutes of CD were the most abundant, and CT had the highest level of PhGs. The results deduced by some macroscopic features in IR fingerprint were in agreement with the HPLC fingerprint of PhGs from the four species, but it should be noted that the IR provided more chemical information than HPLC. In conclusion, with the advantages of high resolution, cost effective and speediness, the macroscopic IR fingerprint method should be a promising analytical technique for discriminating extremely similar herbal medicine, monitoring and tracing the constituents of different extracts and even for quality control of the complex systems such as TCM.

  17. Chemical characteristics combined with bioactivity for comprehensive evaluation of Panax ginseng C.A. Meyer in different ages and seasons based on HPLC-DAD and chemometric methods.

    Science.gov (United States)

    Shan, Si-Ming; Luo, Jian-Guang; Huang, Fang; Kong, Ling-Yi

    2014-02-01

    Panax ginseng C.A. Meyer has been known as a valuable traditional Chinese medicines for thousands years of history. Ginsenosides, the main active constituents, exhibit prominent immunoregulation effect. The present study first describes a holistic method based on chemical characteristic and lymphocyte proliferative capacity to evaluate systematically the quality of P. ginseng in thirty samples from different seasons during 2-6 years. The HPLC fingerprints were evaluated using principle component analysis (PCA) and hierarchical clustering analysis (HCA). The spectrum-efficacy model between HPLC fingerprints and T-lymphocyte proliferative activities was investigated by principal component regression (PCR) and partial least squares (PLS). The results indicated that the growth of the ginsenosides could be grouped into three periods and from August of the fifth year, P. ginseng appeared significant lymphocyte proliferative capacity. Close correlation existed between the spectrum-efficacy relationship and ginsenosides Rb1, Ro, Rc, Rb2 and Re were the main contributive components to the lymphocyte proliferative capacity. This comprehensive strategy, providing reliable and adequate scientific evidence, could be applied to other TCMs to ameliorate their quality control. PMID:24252727

  18. Microleakage of Class II Combined Amalgam-Composite Restorations Using Different Composites and Bonding Agents

    Directory of Open Access Journals (Sweden)

    F. Sharafeddin

    2008-09-01

    Full Text Available Objective: The purpose of the present study was to assess the microleakage of composite restorations with and without a cervical amalgam base and to compare the results of dif-ferent composites and bonding agents.Materials and Methods: One hundred and twenty mesio-occlusal (MO and disto-occlusal (DO Class II cavities were prepared on sixty extracted permanent premolar teeth. The teeth were randomly divided into four groups of 30 and restored as follows:In group A, the mesio-occlusal cavity (MO, Scotchbond multi purpose plus + Z250 and in the disto-occlusal (DO cavity, Prompt-L-Pop + Z250 were applied. As for group B, in the MO and DO cavities, Clearfil SE Bond + Clearfil APX, and varnish + amalgam (In box + Clearfil SE Bond + Clearfil APX were used respectivelywhile in group C; the teeth were restored with amalgam and varnish mesio-occlusally and with amalgam only disto-occlusally. As for group D, varnish + amalgam (in box + Scotchbond multi purpose plus + Z250 were applied mesio-occlusally and Varnish + Amalgam (in box + Prompt–L–Pop + Z250 disto-occlusally.Marginal leakage was assessed by the degree of dye penetration into various sections of the restored teeth. Chi-square and Fisher's exact tests were used for data analysis.Results: Microleakage in gingival margin was more than that in occlusal margin (P<0.05 and microleakage of combined amalgam-composite restorations was significantly lower than that of conventional composite and amalgam restorations.Conclusion: Marginal microleakage decreased by using amalgam at the base of the box in Class II composite restorations.

  19. A rationale for the search for 'missing agents' in cancer combination therapy

    International Nuclear Information System (INIS)

    Many of the agents presently employed for cancer treatment are known to be effective on cycling cells, and are selected on the basis of their main biochemical effect(s) at a cellular level. In the better instances, the agents are chosen according to the age-response they elicit during the cell cycle or at a clinical level, according to pharmacological characteristics. An important cell subpopulation target is represented by non-proliferative, potentially clonogenic cells which are present in human and experimental solid tumours. The search for agents lethally active on such cells has not been particularly successful. Few agents are known to kill preferentially plateau-phase cells, but the differential effects observed are not such that clinical effectiveness could be easily improved. Agents of this lethally specific type are still missing from the battery of the antineoplastic drugs, especially as far as non-alkylating agents are concerned, and screening in this direction should be actively pursued. A better knowledge of the possible relation between plateau-phase sensitivity and cell ability (or inability) to repair sublethal and potentially lethal damage is also necessary. Another (potentially) important subpopulation target is represented by non-proliferating cells recalled into cycle by intrinsic and/or treatment-dependent homeostatic mechanisms. Cells of this type are known to go through an elongated pre-replicative stage in which RNA synthesis plays a specific role. The search for agents lethally active in this stage is still in its infancy. The possible use of these agents entails a better knowledge of recruitment and repopulation kinetics after (initial) treatment(s) and of population synchrony phenomena. Finally, there is the problem of discovering specific antimetastatic agents, that is, agents effective against tumour cells which are going to be entrapped and grow in organs distant from the primary. Drugs such as ICRF 159 appear to be both cytotoxic in

  20. Standardization of homocysteine on HPLC using DTT as reductant

    OpenAIRE

    Ashavaid, Tester F.; Eghlim, Farah F.; Shalia, Kavita K.; Nair, Kappiareth G.

    2003-01-01

    Determination of plasma total homocysteine by high-pressure liquid chromatography (HPLC) usually requires reduction of protein bound or free homocysteine-disulphides into thiols by a reducing agent and the liberated thiols are then derivatized by a fluorescent marker. In this study we have standardized the HPLC method for homocysteine measurement using dithiothreitol (DTT) as reductant.

  1. Performance analyses of a neutralizing agent combination strategy for the production of succinic acid by Actinobacillus succinogenes ATCC 55618.

    Science.gov (United States)

    Wang, Cheng-Cheng; Zhu, Li-Wen; Li, Hong-Mei; Tang, Ya-Jie

    2012-05-01

    A neutralizing agent combination strategy was developed to enhance the succinic acid production by Actinobacillus succinogenes ATCC 55618. First, a maximal succinic acid production of 48.2 g/L was obtained at a culture pH of 7.5. Second, NaOH and KOH were screened to identify the optimal neutralizing agent for pH control. However, the production of succinic acid did not increase, and severe cell flocculation was observed due to a high concentration of metal ions when only one neutralizing agent was used to control pH. Finally, a neutralizing agent combination strategy was developed with a supply of neutralizing agents with OH(-) and carbonate. The cell flocculation was eliminated, and a maximum succinic acid production of 59.2 g/L was obtained with 5 M NaOH and 40 g/L of MgCO(3); this production was 27.9% higher than that obtained with NaOH alone. The results obtained in this study may be useful for the large-scale industrial production of succinic acid. PMID:22002101

  2. High-resolution bacterial growth inhibition profiling combined with HPLC-HRMS-SPE-NMR for identification of antibacterial constituents in Chinese plants used to treat snakebites

    DEFF Research Database (Denmark)

    Liu, Yueqiu; Nielsen, Mia; Stærk, Dan;

    2014-01-01

    Ethnopharmacogical relevance Bacterial infection is one of the main secondary infections caused by snakebite. The 88 plant species investigated in this study have been used as folk remedies for treatment of snakebite, and it is therefore the aim of this study to investigate whether the plants...... contain compounds with bacterial growth inhibition. Materials and methods The water and ethanol extracts of 88 plant species were screened at 200 μg/mL against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa for their antibacterial activity by micro-broth dilution...... assay. The most active extracts were fractionated into microplates using analytical-scale RP-HPLC, and subsequently growth inhibition was assessed for each well. The biochromatograms constructed from these assays were used to identify compounds responsible for antibacterial activity. The structures of...

  3. Excellent combination of HPLC-RSD-DAD-ESI/MS and HSCCC experiments to screen and identify radical scavengers from Neo-Taraxacum siphonanthun

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xinyu; Shi, Shuyun; Zhang, Yuping; Chen, Xiaoqing, E-mail: jiangxinyu@mail.csu.edu.c [Central South University, Changsha (China). School of Chemistry and Chemical Engineering

    2010-07-01

    Our previous research found that the crude extract of Neo-T. siphonanthun exhibited an effective DPPH (1,1-diphenyl-2-picryhydrazyl) radical scavenging activity. In this study an online rapid screening method, high-performance liquid chromatography-radical scavenging detection-diode array detector-electrospray ionization mass spectrometry (HPLC-RSD- DAD-ESI/MS) system, was developed for screening individual antioxidants from the most active fraction. Accordingly, three isomeric derivatives were detected. The target active compounds were isolated by highspeed counter-current chromatography (HSCCC) with the purity over 99%, and were identified as luteolin-3'-O-{beta}-D-glucopyranoside (1), luteolin-7-O-{beta}-D-glucopyranoside (2) and luteolin-4'- O-{beta}-D-glucopyranoside (3) by analysis of its off-line nuclear magnetic resonance (NMR) spectra. Antioxidant activity of three compounds was assessed by off-line DPPH assay, and all of them showed potent activity. (author)

  4. Excellent combination of HPLC-RSD-DAD-ESI/MS and HSCCC experiments to screen and identify radical scavengers from Neo-Taraxacum siphonanthun

    International Nuclear Information System (INIS)

    Our previous research found that the crude extract of Neo-T. siphonanthun exhibited an effective DPPH (1,1-diphenyl-2-picryhydrazyl) radical scavenging activity. In this study an online rapid screening method, high-performance liquid chromatography-radical scavenging detection-diode array detector-electrospray ionization mass spectrometry (HPLC-RSD- DAD-ESI/MS) system, was developed for screening individual antioxidants from the most active fraction. Accordingly, three isomeric derivatives were detected. The target active compounds were isolated by highspeed counter-current chromatography (HSCCC) with the purity over 99%, and were identified as luteolin-3'-O-β-D-glucopyranoside (1), luteolin-7-O-β-D-glucopyranoside (2) and luteolin-4'- O-β-D-glucopyranoside (3) by analysis of its off-line nuclear magnetic resonance (NMR) spectra. Antioxidant activity of three compounds was assessed by off-line DPPH assay, and all of them showed potent activity. (author)

  5. Combining FIPA Agents and Web Services for the Design of Tailorable Groupware Architecture

    OpenAIRE

    Cheaib, Nader; Otmane, Samir; Mallem, Malik

    2008-01-01

    In this paper, we present a new groupware architectural model called UD3, which is based on the integration of web services technologies with software agents. The aim is to design a tailorable groupware architecture using the integration of both technologies, thus using properties of each while reinforcing their individual strengths. In fact, agent-oriented technology is claimed to become the next breakthrough in the development and implementation of large-scale complex systems, while Web ser...

  6. [Exploring an optimal approach to the use of oral hypoglycemic agents based on CGM results: implications for combination therapy with oral hypoglycemic agents].

    Science.gov (United States)

    Mori, Yutaka

    2011-08-01

    In the treatment of type 2 diabetes aimed at prevention of cardiovascular events impacting the prognosis of affected patients, it is critically important not only to lower HbAlc values but to find a way to improve postprandial hyperglycemia without causing hypoglycemia thus minimizing drastic glycemic variations or to maintain favorable glycemic control with daily glycemic variations in mind. In other words, it is no longer adequate to emphasize quantitative reductions in HbAlc as in conventional therapeutic approaches but qualitative glycemic control that takes daily glycemic variations into account is becoming of increasing importance to the management of type 2 diabetes. On the other hand, the 6 oral hypoglycemic agent (OHA) classes currently available for clinical use, i.e., biguanides (BGs), thiazolidinediones (TZDs), alpha-glucosidase inhibitors, sulfonylureas (SUs), fast-acting insulin secretagogues (glinides) and DPP-4 inhibitors, appear to vary from class to class or even from agent from agent within a class in regard to their impact on daily glycemic variations. In our CMG-based study of their impact on glycemic variations, it was demonstrated that BGs and TZDs improve hyperglycemia during nighttime and before breakfast more effectively than they do postprandial glycemic excursions; that, of the insulin secretagogues, glinides reduce daily glycemic variations as do alpha-glucosidase inhibitors, while SUs do not affect them very much; and that DPP-4 inhibitors lower not only mean glucose levels which are deemed equivalent to HbAlc values but also narrow the range of glycemic variations. Thus, OHAs can be broadly classified into those that primarily reduce 24-hour mean glucose levels as equivalent to HbAlc values and those that primarily narrow the range of glycemic variations. Therefore, with either of these agents as monotherapy, it is next to impossible to achieve reductions in HbAlc with a narrow range of glycemic variations, and combination therapy

  7. A Modified Method for Determination of Lumefantrine in Human Plasma by HPLC-UV and Combination of Protein Precipitation and Solid-Phase Extraction: Application to a Pharmacokinetic Study

    Directory of Open Access Journals (Sweden)

    Liusheng Huang

    2010-03-01

    Full Text Available An HPLC-UV method was developed and validated for the determination of lumefantrine in human plasma. Lumefantrine and its internal standard halofantrine were extracted from plasma samples using protein precipitation with acetonitrile (0.2% perchloric acid followed by solid-phase extraction with Hypersep C8 cartridges. Chromatographic separation was performed on a Zorbax SB-CN HPLC column (3.0 × 150 mm, 3.5 μm with water/methanol (0.1% TFA as the mobile phases in a gradient elution mode. Detection was performed using UV/vis detector at λ = 335 nm. The method showed to be linear over a range of 50–10,000 ng/mL with acceptable intra- and inter-day precision and accuracy. The mean recoveries were 88.2% for lumefatrine and 84.5% for the I.S. The internal standard halofantrine is readily available from commercial sources. This method was successfully applied to a pharmacokinetic interaction study between a first-line antimalarial combination (artemether—lumefantrine and antiretroviral therapy.

  8. Edible seaweed as future functional food: Identification of α-glucosidase inhibitors by combined use of high-resolution α-glucosidase inhibition profiling and HPLC-HRMS-SPE-NMR.

    Science.gov (United States)

    Liu, Bingrui; Kongstad, Kenneth T; Wiese, Stefanie; Jäger, Anna K; Staerk, Dan

    2016-07-15

    Crude chloroform, ethanol and acetone extracts of nineteen seaweed species were screened for their antioxidant and α-glucosidase inhibitory activity. Samples showing more than 60% α-glucosidase inhibitory activity, at a concentration of 1 mg/ml, were furthermore investigated using high-resolution α-glucosidase inhibition profiling combined with high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy (HR-bioassay/HPLC-HRMS-SPE-NMR). The results showed Ascophyllum nodosum and Fucus vesicolosus to be rich in antioxidants, equaling a Trolox equivalent antioxidant capacity of 135 and 108 mM Troloxmg(-1) extract, respectively. HR-bioassay/HPLC-HRMS-SPE-NMR showed the α-glucosidase inhibitory activity of A. nodosum, F. vesoculosus, Laminaria digitata, Laminaria japonica and Undaria pinnatifida to be caused by phlorotannins as well as fatty acids - with oleic acid, linoleic acid and eicosapentaenoic acid being the most potent with IC50 values of 0.069, 0.075 and 0.10 mM, respectively, and showing a mixed-type inhibition mode. PMID:26948583

  9. Combinations of Biocontrol Agents for Management of Plant-Parasitic Nematodes and Soilborne Plant-Pathogenic Fungi

    OpenAIRE

    Meyer, Susan L. F.; Roberts, Daniel P.

    2002-01-01

    Numerous microbes are antagonistic to plant-parasitic nematodes and soilborne plant-pathogenic fungi, but few of these organisms are commercially available for management of these pathogens. Inconsistent performance of applied biocontrol agents has proven to be a primary obstacle to the development of successful commercial products. One of the strategies for overcoming inconsistent performance is to combine the disease-suppressive activity of two (or more) beneficial microbes in a biocontrol ...

  10. The Effect of Combined Therapy of Exercise and Nootropic Agent on Cognitive Function in Focal Cerebral Infarction Rat Model

    OpenAIRE

    Song, Min-Keun; Seon, Hyo-Jeong; Kim, In-Gyu; Han, Jae-Young; Choi, In-Sung; Lee, Sam-Gyu

    2012-01-01

    Objective To investigate the effect of combined therapy of exercise and nootropic agent on cognitive function in a focal cerebral infarction rat model. Method Forty 10-week old male Sprague-Dawley rats were subjected to photothrombotic cerebral infarction of the left parietal lobe. All rats were randomly divided into 4 groups: group A was photothrombotic cerebral infarction rats without any treatment (n=10); group B was photothrombotic cerebral infarction rats with swimming exercise (n=10); g...

  11. An agent strategy for automated stock market trading combining price and order book information

    NARCIS (Netherlands)

    Silaghi, G.; Robu, V.

    2005-01-01

    This paper proposes a novel automated agent strategy for stock market trading, developed in the context of the Penn-Lehman automated trading (PLAT) simulation platform by Kearns, M., and Ortiz, L., (2003). We provide a comprehensive experimental validation of our strategy using historic order book d

  12. Temperature-controlled ionic liquid dispersive liquid-phase microextraction combined with HPLC with ultraviolet detector for the determination of fungicides.

    Science.gov (United States)

    Gao, Yuanyuan; Zhou, Qingxiang; Xie, Guohong; Yao, Ziwei

    2012-12-01

    Present study described a simple, environmental benign, easy to operate, and determination method for fungicides including thiram, metalaxyl, diethofencarb, myclobutanil, and tebuconazole. The method is based on temperature-controlled ionic liquid dispersive liquid phase microextraction coupled to HPLC with ultraviolet detector. In the enrichment procedure, ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate [C(8)MIM][PF(6)] was used as the extraction solvent. Variable affecting parameters such as the volume of [C(8)MIM][PF(6)], temperature, extraction time, centrifuging time, and salting-out effect have been optimized in detail. Under the optimal conditions, this method has been found to have good linear relationship in the concentration range of 1.0-100 μg/L and excellent detection sensitivity with LODs (S/N = 3) in the range of 0.32-0.79 μg/L. Precisions of proposed method were in the range of 3.7-5.9% for intraday and 7.8-11.0% for interday (RSDs, n = 6). The proposed method was used for the analysis of real water samples and good spiked recoveries at two different spiked levels were achieved in the range of 84.6-102%. PMID:23166097

  13. Phenolic Profiling of Duchesnea indica Combining Macroporous Resin Chromatography (MRC) with HPLC-ESI-MS/MS and ESI-IT-MS.

    Science.gov (United States)

    Zhu, Mingzhi; Dong, Xia; Guo, Mingquan

    2015-01-01

    Duchesnea indica (D. indica) is an important traditional Chinese medicine, and has long been clinically used to treat cancer in Asian countries. It has been described previously as a rich source of phenolic compounds with a broad array of diversified structures, which are the major active ingredients. However, an accurate and complete phenolic profiling has not been determined yet. In the present work, the total phenolic compounds in crude extracts from D. indica were enriched and fractionated over a macroporous resin column, then identified by HPLC-ESI-MS/MS and ESI-IT-MS (ion trap MS). A total of 27 phenolic compounds were identified in D. indica, of which 21 compounds were identified for the first time. These 27 phenolic compounds encompassing four phenolic groups, including ellagitannins, ellagic acid and ellagic acid glycosides, hydroxybenzoic acid and hydroxycinnamic acid derivatives, and flavonols, were then successfully quantified using peak areas against those of the corresponding standards with good linearity (R² > 0.998) in the range of the tested concentrations. As a result, the contents of individual phenolic compounds varied from 6.69 mg per 100 g dry weight (DW) for ellagic acid to 71.36 mg per 100 g DW for brevifolin carboxylate. Not only did this study provide the first phenolic profiling of D. indica, but both the qualitative identification and the subsequent quantitative analysis of 27 phenolic compounds from D. indica should provide a good basis for future exploration of this valuable medicinal plant. PMID:26694333

  14. Characterization of Flavonoids and Phenolic Acids in Myrcia bella Cambess. Using FIA-ESI-IT-MSn and HPLC-PAD-ESI-IT-MS Combined with NMR

    Directory of Open Access Journals (Sweden)

    Anne L. Dokkedal

    2013-07-01

    Full Text Available The leaves of Myrcia DC. ex Guill species are used in traditional medicine and are also exploited commercially as herbal drugs for the treatment of diabetes mellitus. The present work aimed to assess the qualitative and quantitative profiles of M. bella hydroalcoholic extract, due to these uses, since the existing legislation in Brazil determines that a standard method must be developed in order to be used for quality control of raw plant materials. The current study identified eleven known flavonoid-O-glycosides and six acylated flavonoid derivatives of myricetin and quercetin, together with two kaempferol glycosides and phenolic acids such as caffeic acid, ethil galate, gallic acid and quinic acid. In total, 24 constituents were characterized, by means of extensive preparative chromatographic analyses, along with MS and NMR techniques. An HPLC-PAD-ESI-IT-MS and FIA-ESI-IT-MSn method were developed for rapid identification of acylated flavonoids, flavonoid-O-glycosides derivatives of myricetin and quercetin and phenolic acids in the hydroalcoholic M. bella leaves extract. The FIA-ESI-IT-MS techinique is a powerful tool for direct and rapid identification of the constituents after isolation and NMR characterization. Thus, it could be used as an initial method for identification of authentic samples concerning quality control of Myrcia spp extracts.

  15. Dispersive liquid-phase microextraction in combination with HPLC for the enrichment and rapid determination of benzoylurea pesticides in environmental water samples.

    Science.gov (United States)

    Zhou, Qingxiang; Wang, Guoqing; Xie, Guohong

    2013-07-01

    Benzoylurea (BU) insecticides have contributed greatly to the output of crops. Their residue in the environment put serious threats on human health and environmental safety. In this study, we have established a new, rapid, and reliable method for the monitoring of typical BU insecticides such as diflubenzuron, flufenoxuron, triflumuron, and chlorfluazuron with dispersive liquid-liquid microextraction prior to HPLC. Chlorobenzene and ethanol were employed as the extraction solvent and disperser solvent, respectively. The possible parameters which would influence the extraction efficiency such as the kinds and volumes of extraction and disperser solvents, extraction time, sample pH, centrifuging time, and salting-out effect were optimized in detail. Under the optimal conditions, the linear range of proposed method was in the range of 1.0-70 μg/L. The detection limits varied from 0.24 to 0.82 μg/L and the precision of the method was <6.5% (RSD, n = 6). The proposed method was validated with real water samples and satisfactory spiked recoveries were achieved. All these results indicate that the proposed method is a low cost, easy to operate, efficient, and sensitive method for the analysis of BU insecticides in water samples. PMID:23630192

  16. Analytical Eco-Scale for Assessing the Greenness of a Developed RP-HPLC Method Used for Simultaneous Analysis of Combined Antihypertensive Medications.

    Science.gov (United States)

    Mohamed, Heba M; Lamie, Nesrine T

    2016-09-01

    In the past few decades the analytical community has been focused on eliminating or reducing the usage of hazardous chemicals and solvents, in different analytical methodologies, that have been ascertained to be extremely dangerous to human health and environment. In this context, environmentally friendly, green, or clean practices have been implemented in different research areas. This study presents a greener alternative of conventional RP-HPLC methods for the simultaneous determination and quantitative analysis of a pharmaceutical ternary mixture composed of telmisartan, hydrochlorothiazide, and amlodipine besylate, using an ecofriendly mobile phase and short run time with the least amount of waste production. This solvent-replacement approach was feasible without compromising method performance criteria, such as separation efficiency, peak symmetry, and chromatographic retention. The greenness profile of the proposed method was assessed and compared with reported conventional methods using the analytical Eco-Scale as an assessment tool. The proposed method was found to be greener in terms of usage of hazardous chemicals and solvents, energy consumption, and production of waste. The proposed method can be safely used for the routine analysis of the studied pharmaceutical ternary mixture with a minimal detrimental impact on human health and the environment. PMID:27492952

  17. Phenolic Profiling of Duchesnea indica Combining Macroporous Resin Chromatography (MRC with HPLC-ESI-MS/MS and ESI-IT-MS

    Directory of Open Access Journals (Sweden)

    Mingzhi Zhu

    2015-12-01

    Full Text Available Duchesnea indica (D. indica is an important traditional Chinese medicine, and has long been clinically used to treat cancer in Asian countries. It has been described previously as a rich source of phenolic compounds with a broad array of diversified structures, which are the major active ingredients. However, an accurate and complete phenolic profiling has not been determined yet. In the present work, the total phenolic compounds in crude extracts from D. indica were enriched and fractionated over a macroporous resin column, then identified by HPLC-ESI-MS/MS and ESI-IT-MS (ion trap MS. A total of 27 phenolic compounds were identified in D. indica, of which 21 compounds were identified for the first time. These 27 phenolic compounds encompassing four phenolic groups, including ellagitannins, ellagic acid and ellagic acid glycosides, hydroxybenzoic acid and hydroxycinnamic acid derivatives, and flavonols, were then successfully quantified using peak areas against those of the corresponding standards with good linearity (R2 > 0.998 in the range of the tested concentrations. As a result, the contents of individual phenolic compounds varied from 6.69 mg per 100 g dry weight (DW for ellagic acid to 71.36 mg per 100 g DW for brevifolin carboxylate. Not only did this study provide the first phenolic profiling of D. indica, but both the qualitative identification and the subsequent quantitative analysis of 27 phenolic compounds from D. indica should provide a good basis for future exploration of this valuable medicinal plant.

  18. Battling resistance mechanisms in antihormonal prostate cancer treatment: Novel agents and combinations.

    Science.gov (United States)

    De Maeseneer, Daan Joost; Van Praet, Charles; Lumen, Nicolaas; Rottey, Sylvie

    2015-07-01

    Prostate cancer (PCa) is a hormone-sensitive disease. Androgen deprivation therapy lowers serum testosterone levels (castration) or blocks the androgen receptor (AR) ligand-binding domain. Especially in metastatic disease, hormonal therapy has been able to delay disease progression, reduce symptoms, and improve overall survival. Despite subsequent disease progression and development of castration resistance, PCa remains AR driven. Secondary hormonal treatments such as abiraterone acetate or enzalutamide have demonstrated increased overall survival. However, new resistance mechanisms to these agents have been identified, and systemic chemotherapy is still needed especially in fast-progressing castration-resistant PCa. Several promising androgen synthesis inhibitors (orteronel and galeterone), AR inhibitors (ARN-509, EPI-001, AZD3514, and ODM-201), and heat shock protein modulators (AT11387, 17-DMAG, STA-9090, and OGX-427) are currently under investigation. The wide variety in upcoming systemic agents underlines the molecular heterogeneity of castration-resistant PCa. This article reviews antihormonal therapy in PCa and resistance mechanisms and focuses on novel and upcoming agents currently in clinical testing. PMID:25708954

  19. Combining agent-based modeling and life cycle assessment for the evaluation of mobility policies.

    Science.gov (United States)

    Florent, Querini; Enrico, Benetto

    2015-02-01

    This article presents agent-based modeling (ABM) as a novel approach for consequential life cycle assessment (C-LCA) of large scale policies, more specifically mobility-related policies. The approach is validated at the Luxembourgish level (as a first case study). The agent-based model simulates the car market (sales, use, and dismantling) of the population of users in the period 2013-2020, following the implementation of different mobility policies and available electric vehicles. The resulting changes in the car fleet composition as well as the hourly uses of the vehicles are then used to derive consistent LCA results, representing the consequences of the policies. Policies will have significant environmental consequences: when using ReCiPe2008, we observe a decrease of global warming, fossil depletion, acidification, ozone depletion, and photochemical ozone formation and an increase of metal depletion, ionizing radiations, marine eutrophication, and particulate matter formation. The study clearly shows that the extrapolation of LCA results for the circulating fleet at national scale following the introduction of the policies from the LCAs of single vehicles by simple up-scaling (using hypothetical deployment scenarios) would be flawed. The inventory has to be directly conducted at full scale and to this aim, ABM is indeed a promising approach, as it allows identifying and quantifying emerging effects while modeling the Life Cycle Inventory of vehicles at microscale through the concept of agents. PMID:25587896

  20. Development of a novel, fast, sensitive method for chromium speciation in wastewater based on an organic polymer as solid phase extraction material combined with HPLC-ICP-MS.

    Science.gov (United States)

    Jia, Xiaoyu; Gong, Dirong; Xu, Bin; Chi, Qiaoqiao; Zhang, Xian

    2016-01-15

    Speciation analysis of inorganic chromium in wastewater is of great significance for the monitoring of environmental pollution. In this work, N,N-bis(2-aminoethyl)ethane-1,2-diamine functionalized poly(chloromethyl styrene-co-styrene) was synthesized, characterized and used as the adsorbent to preconcentrate chromium species in environmental waters by on line solid-phase extraction (SPE). The trace speciation analysis of Cr(III) and Cr(VI) in wastewater has been used by short-column high-performance liquid chromatography hyphenated to inductively coupled plasma spectrometry (HPLC-ICP-MS) after on-line SPE. Cr(III) and Cr(VI) have been adsorbed on the anion exchange column after transforming the cationic Cr(III) to an anionic [Cr(III)-EDTA](-) complex devoid of re-dox reagent, and then eluted rapidly (within seconds) with a very low concentration of tetrabutylammonium hydroxide (TBAH) solution. This method provides a reliable on-line preconcentration method and detection coupled technique. Under the optimized conditions, high enrichment factors have been obtained for Cr(VI) and [Cr(III)-EDTA](-) with 30mL sample solution up to 105 and 128, respectively. The low detection limits of 0.0068ng mL(-1) and 0.0041ng mL(-1), with the relative standard deviations (RSDs) of 4.3% and 3.6% were obtained for Cr(VI) and [Cr(III)-EDTA](-), respectively. The developed method was validated by analyzing Certified Reference Materials GSBZ50027-94, and the spike tests were also performed. At the same time, thanks to the merit of simple operation, rapid adsorption/desorption dynamics, high enrichment and low LODs, the established method was applied to analyze three wastewater samples from different discharge port. PMID:26592590

  1. Ultrasonograpy of VX-2 Liver Tumor in Rabbit Treated by High Intensity Focused Ultrasound Combined with Microbubble Contrast Agent

    Science.gov (United States)

    Xiaojuan, Ji; Jinqing, Li; Zhibiao, Wang; Jianzhong, Zou; Wenzhi, Chen; Jin, Bai

    2007-05-01

    Objective: To assess the value of sonographic appearance and to investigate the sonographic character of VX-2 liver tumor in rabbit treated by high intensity focused ultrasound (HIFU) combined with microbubble contrast agent. Methods: Forty-five rabbits bearing VX-2 tumors were randomly averagely assigned into three groups. In group A irradiation was sustained until the target region became hyperechoic. In group B therapy was stopped as soon as hyperecho occurred, and in group C irradiation time was prolonged to ensure the occurrence of coagulation necrosis. Results: Exposure duration for tumors treated purely with HIFU was the longest, whilst the use of microbubble contrast agent combined with HIFU shortened the exposure duration significantly. The gross examination and ultrasonogram coagulation necrosis area measurements correlated strongly (r=0.986,P<0.05) in the microbubble-enhanced HIFU group. Conclusion: It was feasible to enhance HIFU therapy with microbubble contrast agent. The characteristic change in the ultrasound images made it possible to assess the enhanced HIFU therapeutic efficacy in order to adjust the treatment program.

  2. Selective induction of oxidative stress in cancer cells via synergistic combinations of agents targeting redox homeostasis.

    Science.gov (United States)

    Akladios, Fady N; Andrew, Scott D; Parkinson, Christopher J

    2015-07-01

    Cancer cell resistance to chemotherapy is still a heavy burden that impairs the response of many cancer patients to conventional chemotherapy. Using drug combinations is one therapeutic approach to overcome the developing resistance to any one drug. Oxidative stress is now a generally regarded hallmark of cancer that can be one approach to selectively target cancer cells while sparing normal cells. With the aim of increasing oxidative stress in cancer cells to a lethal set point, we have generated and combined several series of redox active compounds that act at different points of the cellular oxidative cascade. The premise of such combinations is to deplete of endogenous antioxidant defence proteins (e.g., Glutathione) while concomitantly increasing the generation of ROS via metal redox recycling and Fenton chemistry which eventually leads to the disruption of cellular redox homeostasis and induction of cell death. Through this approach, we have identified highly synergistic combinations of two distinctive classes of compounds (Azines and Copper(II) complexes of 2-pyridyl ketone thiosemicarbazones) which are capable of eliminating cancer cells without concomitant increase in toxicity toward normal cells. In one of our most potent combinations, a combination index (CI) value of 0.056 was observed, representing a 17 fold enhancement in activity beyond additive effects. Such new combination regimen of redox active compounds can be one step closer to potentially safer low dose chemotherapy. PMID:26022081

  3. Combining Parameter Space Search and Meta-Learning for Data-Dependent Computational Agent Recommendation

    Czech Academy of Sciences Publication Activity Database

    Kazík, O.; Pešková, K.; Pilát, M.; Neruda, Roman

    Los Alamitos: IEEE Computer Society, 2012 - (Wani, M.; Khoshgoftaar, T.; Zhu, X.; Seliya, N.), s. 36-41 ISBN 978-1-4673-4651-1. [ICMLA 2012. International Conference on Machine Learning and Applications /11./. Boca Raton (US), 12.12.2012-15.12.2012] R&D Projects: GA MŠk(CZ) ME10023; GA ČR GD201/09/H057 Grant ostatní: GA UK(CZ) 629612 Institutional support: RVO:67985807 Keywords : data -mining * meta-learning * multi-agent systems Subject RIV: IN - Informatics, Computer Science

  4. Use of Biologic Agents in Combination with Other Therapies for the Treatment of Psoriasis

    OpenAIRE

    Cather, Jennifer C.; Crowley, Jeffrey J.

    2014-01-01

    Psoriasis is a chronic inflammatory skin disorder, which is associated with a significant negative impact on a patient’s quality of life. Traditional therapies for psoriasis are often not able to meet desired treatment goals, and high-dose and/or long-term use is associated with toxicities that can result in end-organ damage. An improved understanding of the involvement of cytokines in the etiology of psoriasis has led to the development of biologic agents targeting tumor necrosis factor (TNF...

  5. Microleakage of Class II Combined Amalgam-Composite Restorations Using Different Composites and Bonding Agents

    OpenAIRE

    F. Sharafeddin; H. Moradian

    2008-01-01

    Objective: The purpose of the present study was to assess the microleakage of composite restorations with and without a cervical amalgam base and to compare the results of dif-ferent composites and bonding agents.Materials and Methods: One hundred and twenty mesio-occlusal (MO) and disto-occlusal (DO) Class II cavities were prepared on sixty extracted permanent premolar teeth. The teeth were randomly divided into four groups of 30 and restored as follows:In group A, the mesio-occlusal cavity ...

  6. Combination therapy with insulin and oral agents: optimizing glycemic control in patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Yki-Järvinen, Hannele

    2002-01-01

    The United Kingdom Prospective Diabetes Study (UKPDS) showed that tight glycemic control with any of several therapeutic regimens has the potential to significantly reduce the risk for long-term microvascular complications of type 2 diabetes. An important question that remains to be answered is what is the best approach to optimizing glycemic control in patients with this disease. This article reviews results of studies in which insulin was used alone or in combination with oral antidiabetic agents for treatment of patients with type 2 diabetes. Analysis of comparative studies (13 in insulin-naive and 26 in previously insulin-treated patients) showed that combination therapy involving one to two insulin injections per day plus oral therapy is usually more effective than insulin monotherapy for achieving and maintaining glycemic control. Combination treatment for type 2 diabetes can be significantly improved by newly developed preparations that lack the major limitations of older products. Once-daily administration of isophane insulin (NPH insulin) is limited by a 15-18-h duration of action and a peak effect that occurs about 6 h after injection. Insulin glargine, a new insulin analogue developed using recombinant DNA technology, has a flat pharmacodynamic profile and a 24-h duration of action. Results from a recent comparative study indicate that insulin glargine plus oral therapy may provide better post-dinner glucose control as well as less symptomatic and nocturnal hypoglycemia than oral therapy combined with NPH insulin. The studies reviewed in the present article support the conclusion that combination therapy with insulin glargine combined with one or more oral antidiabetic agents may be the treatment of choice for achieving glycemic control in patients with type 2 diabetes. PMID:12324990

  7. Enteric-coated tablet of risedronate sodium in combination with phytic acid, a natural chelating agent, for improved oral bioavailability.

    Science.gov (United States)

    Kim, Jeong S; Jang, Sun W; Son, Miwon; Kim, Byoung M; Kang, Myung J

    2016-01-20

    The oral bioavailability (BA) of risedronate sodium (RS), an antiresorptive agent, is less than 1% due to its low membrane permeability as well as the formation of non-absorbable complexes with multivalent cations such as calcium ion (Ca(2+)) in the gastrointestinal tract. In the present study, to increase oral BA of the bisphosphonate, a novel enteric-coated tablet (ECT) dosage form of RS in combination with phytic acid (IP6), a natural chelating agent recognized as safe, was formulated. The chelating behavior of IP6 against Ca(2+), including a stability constant for complex formulation was characterized using the continuous variation method. Subsequently, in vitro dissolution profile and in vivo pharmacokinetic profile of the novel ECT were evaluated comparatively with that of the marketed product (Altevia, Sanofi, US), an ECT containing ethylenediaminetetraacetic acid (EDTA) as a chelating agent, in beagle dogs. The logarithm of stability constant for Ca(2+)-IP6 complex, an equilibrium constant approximating the strength of the interaction between two chemicals to form complex, was 19.05, which was 3.9-fold (p<0.05) and 1.7-fold (p<0.05) higher than those of Ca(2+)-RS and Ca(2+)-EDTA complexes. The release profile of RS from both enteric-coated dosage forms was equivalent, regardless of the type of chelating agent. An in vivo absorption study in beagle dogs revealed that the maximum plasma concentration and area under the curve of RS after oral administration of IP6-containing ECT were approximately 7.9- (p<0.05) and 5.0-fold (p<0.05) higher than those of the marketed product at the same dose (35mg as RS). Therefore, our study demonstrates the potential usefulness of the ECT system in combination with IP6 for an oral therapy with the bisphosphonate for improved BA. PMID:26594027

  8. Assessments of low emission asphalt mixtures produced using combinations of foaming agents

    Science.gov (United States)

    Mohd Hasan, Mohd Rosli

    The asphalt foaming techniques have been used over the last couple of decades as an alternative to the traditional method of preparing asphalt mixtures. Based on positive feedback from the industry, this study was initiated to explore and evaluate the performance of the Warm Mix Asphalt (WMA) mixture produced through a foaming process using physical and chemical foaming agents, which are ethanol and sodium bicarbonate (NaHCO3), respectively. The success of this project may lead to new theories and provide an environmentally friendly technique to produce asphalt mixtures. This may advance the understanding of the foaming process and improve the performance of WMA to support sustainable development. Theoretically, ethanol can function in the same manner as water but requires less energy to foam due to its lower boiling point, 78°C. During the asphalt foaming process, numerous bubbles were generated by the vaporized ethanol, which significantly increased the volume of the asphalt binder, hence the coating potential of aggregates improves. The sodium bicarbonate was incorporated to enhance the quantity of bubbles and its stability. Therefore, understanding foaming agents, their solubility, chemical reactions, chemical function groups and rheological properties of the foamed binder are essential to help control the foam structure and final properties of the foamed WMA mixture. In order to understand the overall performance of newly developed foaming WMA, this material was evaluated for moisture susceptibility, rutting potential, and resistance to fracture and thermal cracking. The coatability, workability and compactability of foamed asphalt mixtures during production were also evaluated. Based on the results, it was found that the newly proposed foaming WMA has high potential to promote sustainable development by lowering the energy consumption and impacts on the environment. The ethanol is efficient in lowering the viscosity of asphalt binders, enhancing the

  9. Immunological changes following a combined effect of chromic small dose γ-irradiation and toxic agents

    International Nuclear Information System (INIS)

    Immunologic changes under conditions of durable effect of low dose γ-radiation on people in the case of combining radiation with the effect of low concentrations of toxic substances, are studied. Under the above effect, the appearance of deviations from the side of immunologic status is possible. Taking into account the important role of the immunity system in homeostasis preservation and the formation of a series of pathological states it is advisable to use figures, and characteristics inherent in the state of the cell immunity to autoallergic processes to estimate a combined effect of radiation and toxic substances on the organism of people

  10. Photosensitizer decorated iron oxide nanoparticles: bimodal agent for combined hyperthermia and photodynamic therapy

    Science.gov (United States)

    Yang, Zhimou; Xu, Keming; Zhang, Bei; Xu, Bing; Zhang, Xixiang; Chang, Chi K.

    2006-02-01

    As the PDT effect may be enhanced by localized hyperthermia (HT), it would be logical to find a single agent that could bring about these two modalities at precisely the target site for synergism. Since highly localized HT can be induced by magnetic field excitation of superparamagnetic nanoparticles, we report here the design and synthesis of photosensitizer-decorated iron oxide nanoparticles and their tumoricidal effect. Thus, a porphyrin is covalently anchored on the iron oxide nanoparticle via dihydroxybenzene which binds tightly on the surface of the nanoparticle by M-O bond. The morphology of the resultant nanoparticle was studied to show that the crystallinality is not changed and the nanoparticle remains superparamagnetic at room temperature. The conjugate is also strongly fluorescent indicating that the iron oxide hardly affects the optical properties of the surface bound porphyrin moieties. The conjugate is readily taken by cancer cell (Hela cell line) and is able to trigger apoptosis after excitation by light.

  11. Combination effect of recombinant human interleukin-1 alpha with antimicrobial agents.

    OpenAIRE

    Nakamura, S.; Minami, A.; Fujimoto, K; Kojima, T.

    1989-01-01

    Combination effects of recombinant human interleukin-1 alpha with ceftazidime, moxalactam, gentamicin, enoxacin, amphotericin B, miconazole, or an immunoglobulin preparation were evaluated in systemic infections with Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candida albicans in normal mice and systemic infection with P. aeruginosa in mice with leukopenia induced by preadministration of cyclophosphamide. Synergistic effects were generally observed at interleukin-1 alpha doses as low a...

  12. Combined effect of gamma radiation and some fungal control agents on the greasy cut- worm

    International Nuclear Information System (INIS)

    The greasy cut worm, Agrotis ipsilon (Lepidoptera- Noctuidae) is widely distributed all over the world, particularly in moderate and subtropical countries of the northern and southern hemispheres (Kononenko ,2003). The greasy cut worm causes damage to vegetables, cucurbitaceous and industrial crops. The greatest damage is caused to cotton, essential-oil cultures, maize, tobacco, sunflower, tomatoes, sugar beet and potato. The pest can strongly harm vegetables, and also damage seedlings of tree species (pine, maple, and nut). This pest has solitary habits. They commonly feed on seedlings at ground level, cutting off the stem and sometimes dragging the plants into their burrows. The continuous use of chemical pesticides against pests, resistance to the action of pesticides had dramatically evolved. Also, the extensive use of these chemicals has given rise to problems such as residual toxicity (pollution) and harmful effects on beneficial insects, which are natural enemies of target or nontarget pest species. Such problems have become a cause of search for safety pesticides including microbial agents as fungi, bacteria and viruses (Rashed, 1993). The use of radiation to induce dominate lethal mutations in the sterile insect technique (SIT) is now as the major component of many large and successful programs for pest suppression and eradication. Adult insects, and their different developmental stages, differ in their sensitivity to the induction of dominate lethal mutation. Care has to be taken to identify the appropriate dose of radiation that produces the required level of sterility without impairing the overall fitness of the released insects.(Sawires, 2005). This technique would be successful control device for suppressing and combating many lepidopteraus insect pests, including A. Ipsilon has been studied (EL- kady et al., 1983, EL-Naggar et al., 1984, Abd El -Hamid 2004 and Gabarty, 2008). Entomopathogenic fungi that infect insects have received considerable

  13. Tinospora cordifolia as a protective and immunomodulatory agent in combination with cisplatin against murine visceral leishmaniasis.

    Science.gov (United States)

    Sachdeva, Heena; Sehgal, Rakesh; Kaur, Sukhbir

    2014-02-01

    Effect of pure herb, Tinospora cordifolia was studied for its hepatoprotective, nephroprotective and immunomodulatory activity against high dose cisplatin treatment in Leishmania donovani infected BALB/c mice. Administration of cisplatin (5mg/kg b.wt. daily for 5 days, i.p.) reduced the parasite load in L. donovani infected BALB/c mice but produced damage in liver and kidney as manifested biochemically by an increase in serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), serum urea, serum creatinine and various electrolytes etc. These biochemical analyses were further supported by cisplatin induced morphological changes in kidney, liver and spleen. To combat this pure herb, T. cordifolia (100mg/kg b.wt. for 15 days daily) was used in combination with cisplatin in L. donovani infected BALB/c mice and it was found that all the aforementioned changes were effectively attenuated by T. cordifolia when administered in combination with cisplatin. Moreover, flow cytometric analysis of lymphocyte surface markers of T cells (CD3+, CD4+ and CD8+), NK1.1 and B cells (CD19) indicated prominent enhancement in proliferation and differentiation of lymphocytes. T. cordifolia in combination with cisplatin selectively induced Th1 type of immune response as depicted by enhanced levels of IFN-γ and IL-2 whereas Th2 specific cytokines IL-4 and IL-10 observed a moderate decline. Confirmation of Th1 polarization was further obtained from augmented levels of IgG2a over IgG1 and heightened DTH (delayed type hypersensitivity) response. Thus, our results suggest that treatment by T. cordifolia may be a critical remedy for the amelioration of adverse effects of cisplatin. Thus, this might serve as a novel combination against visceral leishmaniasis in future. PMID:24370645

  14. Combining Exception Handling and Replication for Improving the Reliability of Agent Software

    OpenAIRE

    Dony, Christophe; Kchir, Selma; Tibermacine, Chouki; Urtado, Christelle; Vauttier, Sylvain; Ductor, Sylvain; GUESSOUM, Zahia

    2010-01-01

    Exception handling and replication are two complementary mechanisms that increase software reliability. Exception handling helps programmers in controlling situations in which the normal execution flow of a program cannot continue. Replication handles system fail- ures through redundancy. Combining both techniques is a first step to- wards building a trustworthy software engineering framework. This paper presents some of the results from the Facoma project. It proposes the specification of an...

  15. A rapid stability-indicating, fused-core HPLC method for simultaneous determination of β-artemether and lumefantrine in anti-malarial fixed dose combination products

    OpenAIRE

    Wega, Sultan Suleman; Vandercruyssen, Kirsten; Wynendaele, Evelien; D'Hondt, Matthias; Bracke, Nathalie; Duchateau, Luc; Burvenich, Christian; Peremans, Kathelijne; De Spiegeleer, Bart

    2013-01-01

    Background: Artemisinin-based fixed dose combination (FDC) products are recommended by World Health Organization (WHO) as a first-line treatment. However, the current artemisinin FDC products, such as beta-artemether and lumefantrine, are inherently unstable and require controlled distribution and storage conditions, which are not always available in resource-limited settings. Moreover, quality control is hampered by lack of suitable analytical methods. Thus, there is a need for a rapid and s...

  16. In vitro interaction of certain antimicrobial agents in combination with plant extracts against some pathogenic bacterial strains

    Institute of Scientific and Technical Information of China (English)

    Kalpna Rakholiya; Sumitra Chanda

    2012-01-01

    Objective: To evaluate the in vitro interaction between methanolic extracts of Terminalia catappa (Combretaceae) (T. catappa) and Carica papaya (caricaceae) (C. papaya) leaves and certain known antimicrobial drugs like penicillin G (P), ampicillin (AMP), amoxyclav (AMC), cephalothin (CEP), polymyxin B (PB), rifampicin (RIF), amikacin (AK), nilidixic acid (NA), gentamicin (GEN), chloramphenicol (C), ofloxacin (OF) against five Gram positive and five Gram negative bacteria.Methods:Evaluation of synergy interaction between plant extracts and antimicrobial agents was carried out using disc diffusion method. Results: The results of this study showed that there is an increased activity in case of combination of methanolic plant extracts and test antimicrobial agents. The more potent result was that the synergism between methanolic extract of C. papaya and antibiotics showed highest and strong synergistic effect against tested bacterial strains;though methanolic extract of C. papaya alone was not showing any antibacterial activity.Conclusions:These results indicate that combination between plant extract and the antibiotics could be useful in fighting emerging drug-resistance microorganisms.

  17. In vitro interaction of certain antimicrobial agents in combination with plant extracts against some pathogenic bacterial strains

    Institute of Scientific and Technical Information of China (English)

    Kalpna Rakholiya; Sumitra Chanda

    2012-01-01

    Objective: To evaluate the in vitro interaction between methanolic extracts of Terminalia catappa (T. catappa) (Combretaceae) and Carica papaya (C. papaya) (caricaceae) leaves and certain known antimicrobial drugs like penicillin G (P), ampicillin (AMP), amoxyclav (AMC), cephalothin (CEP), polymyxin B (PB), rifampicin (RIF), amikacin (AK), nilidixic acid (NA), gentamicin (GEN), chloramphenicol (C), ofloxacin (OF) against five Gram positive and five Gram negative bacteria. Methods: Evaluation of synergy interaction between plant extracts and antimicrobial agents was carried out using disc diffusion method. Results: The results of this study showed that there is an increased activity in case of combination of methanolic plant extracts and test antimicrobial agents. The more potent result was that the synergism between methanolic extract of C. papaya and antibiotics showed highest and strong synergistic effect against tested bacterial strains;though methanolic extract of C. papaya alone was not showing any antibacterial activity. Conclusions: These results indicate that combination between plant extract and the antibiotics could be useful in fighting emerging drug-resistance microorganisms.

  18. Combined radiation-protective and radiation-sensitizing agents. IV. Measurement of intracellular protector concentrations

    International Nuclear Information System (INIS)

    Radiosensitization of hypoxic V79 Chinese hamster cells by 0.5 mM misonidazole at approximately 0-4 degrees C is substantially enhanced by pretreating the cells overnight with 0.1 mM buthionine sulfoximine, which lowers the cellular glutathione content to 5% of control values (from 4 mM to approximately 0.2 mM). The enhanced sensitization is reversed by concentrations of exogenous cysteine that are much lower (0.02 mM) than the original glutathione content. Reduced Co-enzyme A affords reversal of the enhancing effect at concentrations of about 1 mM. Sodium ascorbate gives no protection at all even at concentrations of 2 mM. The intracellular concentration of the reducing agents was measured using a spin-through oil technique. There was no diffusion of Co-A (MW greater than 750) or ascorbate (excluded by charge) into the cells. In contrast, cysteine was rapidly concentrated by factors of 4-10, even at the low temperatures used. Extracellular ascorbate's inability to radioprotect argues against electron transfer across the cell membrane as a mechanism for radioprotection. This mechanism could have explained the ability of exogenous thiols to radioprotect in former studies using glutathione, and in the present studies using Co-A. The potential of cysteine to be concentrated by cells poses a problem in the interpretation of exogenous protection by non-diffusing thiols, since trace contamination by cysteine could lead to the actual protection observed. Cysteine could also be formed by exchange reactions of exogenous thiols with the disulfide of cysteine, present in all media formulations

  19. Development and Validation of a New Rp-Hplc Method For Simultaneous Estimation of N-Acetylcysteine And L – Arginine In Combined Dosage form

    Directory of Open Access Journals (Sweden)

    Nalluri Naga Jyothi

    2014-09-01

    Full Text Available An isocratic, reversed phase-liquid chromatographic method was developed for quantitative determination of N-acetylcysteine and L-Arginine in combined dosage form. A Waters Xterra Rp8, (150*4.6*5µm column with a mobile phase containing a Phosphate Buffer (pH 4.5 and Methanol (90: 10 v/v was used. The flow rate was maintained at 0.8 ml/min, column temperature at 30°C and effluents were monitored at 248 nm. The retention times of N-acetylcysteine and L-Arginine were found to be 2.697 min and 3.156 min, respectively. The correlation co-efficient for N-acetylcysteine and L-Arginine was found to be 0.99 and 0.99, respectively. The proposed method was validated with respect to linearity, accuracy, precision, specificity, and robustness. Recovery of N-acetylcysteine and L-Arginine in formulations was found to be in the range of 97-103% and 97-103% respectively confirms the non-interferences of the excipients in formulation. Due to its simplicity, rapidness and high precision, this method can be successfully applied for estimation of N-acetylcysteine and L-Arginine in combined pharmaceutical dosage forms.

  20. Glucan–Resveratrol–Vitamin C Combination Offers Protection against Toxic Agents

    Directory of Open Access Journals (Sweden)

    Jana Vetvickova

    2012-11-01

    Full Text Available Biological immunomodulators are routinely evaluated as a natural source of molecules with profound effects on the immune system. They belong to a group of physiologically active compounds, collectively termed biological response modifiers. Most of the studies were focused on immune system stimulation. Recently, they have become the focus of studies seeking molecules that are able to overcome negative effects of various immunotoxins. This paper concentrates on the effects of a glucan/resveratrol/vitamin C combination on immunosuppressive effects of mercury and perfluorinated hydrocarbons. Effects described in this review have strong clinical potential, as environmental contaminants have adverse effects on all aspects of the immune system and represent a serious threat to the health of both humans and animals.

  1. Development and Validation of an RP-HPLC Method for Estimation of Chlorpheniramine Maleate, Ibuprofen, and Phenylephrine Hydrochloride in Combined Pharmaceutical Dosage Form

    Directory of Open Access Journals (Sweden)

    Pinak M. Sanchaniya

    2013-01-01

    Full Text Available The objective of this paper is to develope a simple, precise, accurate, and reproducible reversed phase high performance liquid chromatographic method for the quantitative determination of chlorpheniramine maleate, ibuprofen, and phenylephrine hydrochloride in combined pharmaceutical dosage form. Analysis was carried out using acetonitrile : mathanol : phoshphate buffer (50 : 20 : 30, v/v/v, pH 5.6 mobile phase at 1.0 mL/min flow rate and Sunfire C 18 column (5 μm × 250 mm × 4.6 mm as stationary phase with detection wavelength of 220 nm. The retention times of chlorpheniramine maleate (CPM, ibuprofen (IBU, and phenylephrine hydrochloride (PHE were 4.2 min, 13.6 min, and 2.7 min, respectively. The proposed method was validated with respect to linearity, accuracy, precision, specificity, and robustness. The linearity for chlorpheniramine maleate, ibuprofen, and phenylephrine hydrochloride was in the range of 0.5–2.5 μg/mL, 25–125 μg/mL, and 1.25–6.25 μg/mL, respectively. The % recoveries of all the three drugs were found to be 99.44–101.61%, 99.39–101.79%, and 98.66–101.83%. LOD were found to be 32, 120, and 68 ng/mL for CPM, IBU, and PHE, respectively. The method was successfully applied to the estimation of chlorpheniramine maleate, ibuprofen, and phenylephrine hydrochloride in combined pharmaceutical dosage form.

  2. Combined intra-arterial thrombolysis and neuprotectant agents reduce cerebral infarction in rabbits with experimental acute cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Pei Shi

    2006-01-01

    BACKGROUND:The intra-arterial thrombolytic therapy is one of main methods for more patients to obtain bene-fits.The percentage of arterial recanalization treated with intre-arterial therapy is higher than with intra-venous therapy.next,the dose of thrombolytic medicines is lower and the therapeutic time window may be possibly longer.Related researches are focus on intra-artedal thrombolysis combining with neuprotectant agents to treat acute ischemic stroke.The results show that combination of them can further prolong the therapeutic time window.improve the percentage of arterial recanalization and reduce cerebral infarction volume.OBJECTIVE:To observe the effect of single thmmbolitic therapy combined with neuroprotectant agents in the treatment of acute ischemic stroke.DESIGN:Randomized block design.SETTING:Xinhua Hospital of Xixiang City.Henan Province.MATERIALS:Thirty-six adult male white rabbits.weighing 1.5-2.0 kg.dean grade.were provided by Expedmental Animal Center of Xinxiang Medical College.All rabbits were randomly divided into three groups:intra-arterial thrombolysis control group.corenalin control group and combination group with 12 in each group.Urekinase was provided by Beijing Saisheng Pharmaceutical Co.,Ltd.(batch number:020923);corenalin by Sanjing Pharmaceutical Co.,Ltd.of Harbin Pharmacautical Group(batch number:021106):nimodipine by Shandong Xihua Pharmaceutical Co.,Ltd.(batch number:020611):contrast medium IOPAMlR0300 by Bracco s.P.a.Milano italian (batch number:0584);2,3,5-triphenyltetrazolium chloride(TTC)by Beijing Mashi Fine ChemicaL Product Co.,Ltd.(batch number:020926).METHODS: The experiment was camed out in the Department of Intervention. Second People's Hospital of Xinxiang from September 2002 to May 2003.①According to techniques of Benes et al and Zhu et al,animal models with acute ischemia were established.Two hours later.the therapy began.Intra-artedal thrombolysis control group:5 000 U/kg urokinase was dripped in Ieft common

  3. HPLC Neurotransmitter Analysis.

    Science.gov (United States)

    Holm, Thomas Hellesøe; Isaksen, Toke Jost; Lykke-Hartmann, Karin

    2016-01-01

    High performance liquid chromatography (HPLC) is a powerful tool to measure neurotransmitter levels in specific tissue samples and dialysates from patients and animals. In this chapter, we list the current protocols used to measure neurotransmitters in the form of biogenic amines from murine brain samples. PMID:26695044

  4. HPLC of Steroids

    Czech Academy of Sciences Publication Activity Database

    Dinan, L.; Harmatha, Juraj; Lafont, R.

    Boca Raton : CRC Press, 2010, s. 679-708 ISBN 9781420092608. - (Chromatographic Science Series. 102) Institutional research plan: CEZ:AV0Z40550506 Keywords : HPLC * sterols * ecdysteroids * steroidal saponins Subject RIV: CC - Organic Chemistry http://www.crcpress.com/product/isbn/9781420092608

  5. Rapid analysis of aflatoxins B1, B2, and ochratoxin A in rice samples using dispersive liquid-liquid microextraction combined with HPLC.

    Science.gov (United States)

    Lai, Xian-Wen; Sun, Dai-Li; Ruan, Chun-Qiang; Zhang, He; Liu, Cheng-Lan

    2014-01-01

    A novel, simple, and rapid method is presented for the analysis of aflatoxin B1, aflatoxin B2, and ochratoxin A in rice samples by dispersive liquid-liquid microextraction combined with LC and fluorescence detection. After extraction of the rice samples with a mixture of acetonitrile/water/acetic acid, mycotoxins were rapidly partitioned into a small volume of organic solvent (chloroform) by dispersive liquid-liquid microextraction. The three mycotoxins were simultaneously determined by LC with fluorescence detection after precolumn derivatization for aflatoxin B1 and B2. Parameters affecting both extraction and dispersive liquid-liquid microextraction procedures, including the extraction solvent, the type and volume of extractant, the volume of dispersive solvent, the addition of salt, the pH and the extraction time, were optimized. The optimized protocol provided an enrichment factor of approximately 1.25 and with detection of limits (0.06-0.5 μg/kg) below the maximum levels imposed by current regulations for aflatoxins and ochratoxin A. The mean recovery of three mycotoxins ranged from 82.9-112%, with a RSD less than 7.9% in all cases. The method was successfully applied to measure mycotoxins in commercial rice samples collected from local supermarkets in China. PMID:24243826

  6. Comparative Assessment of Complex Stabilities of Radiocopper Chelating Agents by a Combination of Complex Challenge and in vivo Experiments.

    Science.gov (United States)

    Litau, Shanna; Seibold, Uwe; Vall-Sagarra, Alicia; Fricker, Gert; Wängler, Björn; Wängler, Carmen

    2015-07-01

    For (64) Cu radiolabeling of biomolecules to be used as in vivo positron emission tomography (PET) imaging agents, various chelators are commonly applied. It has not yet been determined which of the most potent chelators--NODA-GA ((1,4,7-triazacyclononane-4,7-diyl)diacetic acid-1-glutaric acid), CB-TE2A (2,2'-(1,4,8,11-tetraazabicyclo[6.6.2]hexadecane-4,11-diyl)diacetic acid), or CB-TE1A-GA (1,4,8,11-tetraazabicyclo[6.6.2]hexadecane-4,11-diyl-8-acetic acid-1-glutaric acid)--forms the most stable complexes resulting in PET images of highest quality. We determined the (64) Cu complex stabilities for these three chelators by a combination of complex challenge and an in vivo approach. For this purpose, bioconjugates of the chelating agents with the gastrin-releasing peptide receptor (GRPR)-affine peptide PESIN and an integrin αv β3 -affine c(RGDfC) tetramer were synthesized and radiolabeled with (64) Cu in excellent yields and specific activities. The (64) Cu-labeled biomolecules were evaluated for their complex stabilities in vitro by conducting a challenge experiment with the respective other chelators as challengers. The in vivo stabilities of the complexes were also determined, showing the highest stability for the (64) Cu-CB-TE1A-GA complex in both experimental setups. Therefore, CB-TE1A-GA is the most appropriate chelating agent for *Cu-labeled radiotracers and in vivo imaging applications. PMID:26011290

  7. Revitalization of pioglitazone: the optimum agent to be combined with a sodium-glucose co-transporter-2 inhibitor.

    Science.gov (United States)

    DeFronzo, R A; Chilton, R; Norton, L; Clarke, G; Ryder, R E J; Abdul-Ghani, M

    2016-05-01

    The recently completed EMPA-REG study showed that empagliflozin significantly decreased the major adverse cardiac events (MACE) endpoint, which comprised cardiovascular death, non-fatal myocardial infarction (MI) and stroke, in patients with high-risk type 2 diabetes (T2DM), primarily through a reduction in cardiovascular death, without a significant decrease in either MI or stroke. In the PROactive study, pioglitazone decreased the MACE endpoint by a similar degree to that observed in the EMPA-REG study, through a marked reduction in both recurrent MI and stroke and a modest reduction in cardiovascular death. These observations suggest that pioglitazone might be an ideal agent to combine with empagliflozin to further reduce cardiovascular events in patients with high-risk diabetes as empagliflozin also promotes salt/water loss and would be expected to offset any fluid retention associated with pioglitazone therapy. In the present paper, we provide an overview of the potential benefits of combined pioglitazone/empagliflozin therapy to prevent cardiovascular events in patients with T2DM. PMID:26919068

  8. Effect of Combination of Steel Fiber and MgO-type Expansive Agent on Properties of Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Aiguo; DENG Min; SUN Daosheng; MO Liwu; WANG Jun; TANG Mingshu

    2011-01-01

    The effect of combination of steel fiber and MgO-type expansive agent(MEA)on strength,air-permeability and porosity of concrete was investigated.The porosity and air-permeability of concrete were determined by method of evaporated water and Torrent permeability tester,respectively.Pore structures of mortars in concrete were analyzed using mercury intrusion porosimetry(MIP).Interfacial structures between steel fibers and matrix were examined by use of optical microscope.The experimental results show that improvement of pore structures of mortar and fiber-matrix interfacial structure in concrete by combination of steel fiber and MEA may remarkably increase properties of concrete.In comparison with plain concrete,compressive strength and splitting tensile strength of steel fiber reinforced expansive concrete increased by 15.3% and 38.1%,permeability coefficient K(t),penetration depth L and porosity of concrete decreased by 41.1%,21.3% and 13.1% at 28 days,respectively.

  9. Simultaneous analysis of ellagic acid and coenzyme Q(10) by derivative spectroscopy and HPLC.

    Science.gov (United States)

    Ratnam, D Venkat; Bhardwaj, V; Kumar, M N V Ravi

    2006-09-15

    Antioxidants are gaining tremendous interest as chemopreventive as well as chemotherapeutic agents. Ellagic acid (EA) is a plant derived compound with very poor solubility in water and very low octanol/water partition coefficient and coenzyme Q(10) (CoQ(10)) is a highly lipophilic compound, which is synthesized in the body and can be derived from food supplements as well. The new insights in the combination therapy are promising a better future in many challenging diseases. Synergism is among the key advantages of combination therapy apart from decreased intensity of unwanted effects of a compound, increased patient compliance and reduction in cost of therapy. EA and CoQ(10) supplementation in combination will be beneficial in strengthening the weakened antioxidant defense system in many diseases related to oxidative stress. Here we report first derivative UV spectroscopic and HPLC methods for the simultaneous analysis of these two agents in pharmaceutical preparations. Results obtained indicate that the derivative spectroscopy is as efficient as HPLC method in quantitative analysis. Retention of ellagic acid can be increased using PEG bonded column which is poorly retained on C(18) column. PEG column can be used for rapid simultaneous analysis of EA and CoQ(10), which are having diverse physicochemical properties. PMID:18970780

  10. Combination of Vessel-Targeting Agents and Fractionated Radiation Therapy: The Role of the SDF-1/CXCR4 Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Fang-Hsin; Fu, Sheng-Yung [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Taiwan (China); Yang, Ying-Chieh [Department of Radiation Oncology, National Taiwan University Hospital Hsin-Chu Branch, Taiwan (China); Wang, Chun-Chieh [Department of Radiation Oncology, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Department of Medical Imaging and Radiological Science, Chang Gung University, Taiwan (China); Chiang, Chi-Shiun, E-mail: cschiang@mx.nthu.edu.tw [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Taiwan (China); Hong, Ji-Hong, E-mail: jihong@adm.cgmh.org.tw [Department of Radiation Oncology, Chang Gung Memorial Hospital-LinKou, Taiwan (China); Department of Medical Imaging and Radiological Science, Chang Gung University, Taiwan (China)

    2013-07-15

    Purpose: To investigate vascular responses during fractionated radiation therapy (F-RT) and the effects of targeting pericytes or bone marrow-derived cells (BMDCs) on the efficacy of F-RT. Methods and Materials: Murine prostate TRAMP-C1 tumors were grown in control mice or mice transplanted with green fluorescent protein-tagged bone marrow (GFP-BM), and irradiated with 60 Gy in 15 fractions. Mice were also treated with gefitinib (an epidermal growth factor receptor inhibitor) or AMD3100 (a CXCR4 antagonist) to examine the effects of combination treatment. The responses of tumor vasculatures to these treatments and changes of tumor microenvironment were assessed. Results: After F-RT, the tumor microvascular density (MVD) was reduced; however, the surviving vessels were dilated, incorporated with GFP-positive cells, tightly adhered to pericytes, and well perfused with Hoechst 33342, suggesting a more mature structure formed primarily via vasculogenesis. Although the gefitinib+F-RT combination affected the vascular structure by dissociating pericytes from the vascular wall, it did not further delay tumor growth. These tumors had higher MVD and better vascular perfusion function, leading to less hypoxia and tumor necrosis. By contrast, the AMD3100+F-RT combination significantly enhanced tumor growth delay more than F-RT alone, and these tumors had lower MVD and poorer vascular perfusion function, resulting in increased hypoxia. These tumor vessels were rarely covered by pericytes and free of GFP-positive cells. Conclusions: Vasculogenesis is a major mechanism for tumor vessel survival during F-RT. Complex interactions occur between vessel-targeting agents and F-RT, and a synergistic effect may not always exist. To enhance F-RT, using CXCR4 inhibitor to block BM cell influx and the vasculogenesis process is a better strategy than targeting pericytes by epidermal growth factor receptor inhibitor.

  11. Effects of combined treatment with rapamycin and cotylenin A, a novel differentiation-inducing agent, on human breast carcinoma MCF-7 cells and xenografts

    OpenAIRE

    Kasukabe, Takashi; Okabe-Kado, Junko; Kato, Nobuo; Sassa, Takeshi; Honma, Yoshio

    2005-01-01

    Introduction Rapamycin, an inhibitor of the serine/threonine kinase target of rapamycin, induces G1 arrest and/or apoptosis. Although rapamycin and its analogues are attractive candidates for cancer therapy, their sensitivities with respect to growth inhibition differ markedly among various cancer cells. Using human breast carcinoma cell line MCF-7 as an experimental model system, we examined the growth-inhibitory effects of combinations of various agents and rapamycin to find the agent that ...

  12. A highly sensitive HPLC-MS/MS method for quantification of 20(S)-protopanaxadiol in human plasma and its application in phase IIa clinical trial of a novel antidepressant agent.

    Science.gov (United States)

    Ling, Jin; Yu, Yingjia; Zhu, Jiajun; Li, Yan; Ling, Li; Wang, Liping; Xu, Changjiang; Duan, Gengli

    2016-09-15

    A highly sensitive HPLC-MS/MS assay method was established to quantify 20(S)-protopanaxadiol (PPD) in human plasma with dexamethasone as an internal standard. The electrospray ion mass spectrometry (ESI-MS) was operated under the multiple reactions monitoring mode (MRM) using positive ion mode. PPD was extracted from 500μL plasma samples by liquid-liquid extraction then separated by a C18 analytical column with gradient elution. The concentration of PPD could be determined by this HPLC-MS/MS method over the range of 0.05-20ng/mL with the lower limit of quantification (LLOQ) of 0.05ng/mL. The method was successfully applied to phase IIa clinical trial of Yuxintine (PPD capsule) in which plasma samples of 87 subjects were analyzed following 6 weeks of oral administration of placebo or PPD capsules in 5 different doses. In this study, the measured concentration was linearly related to the oral dosage with R=0.9901. The minimum and maximum values of measured concentration were 0.06 and 11.60ng/mL, respectively. In addition, plasma concentrations of PPD in depression patients were reported for the first time in our study. PMID:27507666

  13. Combined intra-arterial thrombolysis and neuprotectant agents reduce cerebral infarction in rabbits with experimental acute cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Pei Shi

    2006-01-01

    BACKGROUND:The intra-arterial thrombolytic therapy is one of main methods for more patients to obtain bene-fits.The percentage of arterial recanalization treated with intre-arterial therapy is higher than with intra-venous therapy.next,the dose of thrombolytic medicines is lower and the therapeutic time window may be possibly longer.Related researches are focus on intra-artedal thrombolysis combining with neuprotectant agents to treat acute ischemic stroke.The results show that combination of them can further prolong the therapeutic time window.improve the percentage of arterial recanalization and reduce cerebral infarction volume.OBJECTIVE:To observe the effect of single thmmbolitic therapy combined with neuroprotectant agents in the treatment of acute ischemic stroke.DESIGN:Randomized block design.SETTING:Xinhua Hospital of Xixiang City.Henan Province.MATERIALS:Thirty-six adult male white rabbits.weighing 1.5-2.0 kg.dean grade.were provided by Expedmental Animal Center of Xinxiang Medical College.All rabbits were randomly divided into three groups:intra-arterial thrombolysis control group.corenalin control group and combination group with 12 in each group.Urekinase was provided by Beijing Saisheng Pharmaceutical Co.,Ltd.(batch number:020923);corenalin by Sanjing Pharmaceutical Co.,Ltd.of Harbin Pharmacautical Group(batch number:021106):nimodipine by Shandong Xihua Pharmaceutical Co.,Ltd.(batch number:020611):contrast medium IOPAMlR0300 by Bracco s.P.a.Milano italian (batch number:0584);2,3,5-triphenyltetrazolium chloride(TTC)by Beijing Mashi Fine ChemicaL Product Co.,Ltd.(batch number:020926).METHODS: The experiment was camed out in the Department of Intervention. Second People's Hospital of Xinxiang from September 2002 to May 2003.①According to techniques of Benes et al and Zhu et al,animal models with acute ischemia were established.Two hours later.the therapy began.Intra-artedal thrombolysis control group:5 000 U/kg urokinase was dripped in Ieft common

  14. Sofalcone, a mucoprotective agent, increases the cure rate of Helicobacter pyloriinfection when combined with rabeprazole, amoxicillin and clarithromycin

    Institute of Scientific and Technical Information of China (English)

    Hajime Isomoto; Hisashi Furusu; Ken Ohnita; Chun-Yang Wen; Kenichiro Inoue; Shigeru Kohno

    2005-01-01

    AIM: The mucoprotective agents, sofalcone and polaprezinc have anti-Helicobacter pylori ( H pylori)activities. We determined the therapeutic effects of sofalcone and polaprezinc when combined with rabeprazole,amoxicillin and clarithromycin for Helicobacter pylori infection.METHODS: One hundred and sixty-five consecutive outpatients with peptic ulcer and H pylori infection were randomly assigned to one of the following three groups and medicated for 7 d. Group A: triple therapy with rabeprazole (10 mg twice daily), clarithromycin (200 mg twice daily) and amoxicillin (750 mg twice daily). Group B: sofalcone (100 mg thrice daily) plus the triple therapy.Group C: polaprezinc (150 mg twice daily) plus the triple therapy. Eradication was considered successful if 13C-urea breath test was negative at least 4 wk after cessation of eradication regimens or successive famotidine in the cases of active peptic ulcer.RESULTS: On intention-to-treat basis, H pyloricure wasachieved in 43 of 55 (78.2%) patients, 47 of 54 (87.0%)and 45 of 56 (80.4%) for the groups A, B and Crespectively. Using per protocol analysis, the eradication rates were 81.1% (43/53), 94.0% (47/50) and 84.9% (45/53) respectively. There was a significant difference in the cure rates between group A and B. Adverse events occurred in 10, 12 and 11 patients, from groups A, B and C respectively, but the events were generally mild.CONCLUSION: The addition of sofalcone, but not polaprezinc, significantly increased the cure rate of H pylori infection when combined with the rabeprazole-amoxicillinclarithromycin regimen.

  15. Floating tablets for controlled release of ofloxacin via compression coating of hydroxypropyl cellulose combined with effervescent agent.

    Science.gov (United States)

    Qi, Xiaole; Chen, Haiyan; Rui, Yao; Yang, Fengjiao; Ma, Ning; Wu, Zhenghong

    2015-07-15

    To prolong the residence time of dosage forms within gastrointestinal trace until all drug released at desired rate was one of the real challenges for oral controlled-release drug delivery system. Herein, we developed a fine floating tablet via compression coating of hydrophilic polymer (hydroxypropyl cellulose) combined with effervescent agent (sodium bicarbonate) to achieve simultaneous control of release rate and location of ofloxacin. Sodium alginate was also added in the coating layer to regulate the drug release rate. The effects of the weight ratio of drug and the viscosity of HPC on the release profile were investigated. The optimized formulations were found to immediately float within 30s and remain lastingly buoyant over a period of 12 h in simulated gastric fluid (SGF, pH 1.2) without pepsin, indicating a satisfactory floating and zero-order drug release profile. In addition, the oral bioavailability experiment in New Zealand rabbits showed that, the relative bioavailability of the ofloxacin after administrated of floating tablets was 172.19%, compared to marketed common release tablets TaiLiBiTuo(®). These results demonstrated that those controlled-released floating tables would be a promising gastro-retentive delivery system for drugs acting in stomach. PMID:25956047

  16. Internal surface reverse phase HPLC

    International Nuclear Information System (INIS)

    Two recent goals in the field o nuclear medicine have been the development of 99m-Technetium radiopharmaceuticals for diagnostic perfusion imaging of the heart and brain. The neutral seven coordinate technetium compounds known as the BATOs (boronic acid adducts of technetium dioximes) with the general formula TcCl(dioxime)3BR (BR = Boronic Acid Adduct) have shown their utility as both myocardial and cerebral perfusion agents. Variability in serum binding and metabolism between animal models and humans is of major concern when determining the potential clinical utility of 99m-Tc radiopharmaceuticals from animal data. This paper introduces an in vitro method that has been developed which permits interspecies comparisons of serum binding and metabolism of the TcCl(dioxime)3BR radiopharmaceuticals. The method involves the HPLC analysis of TcCl(dioxime)3BR samples incubated in sera using a two column system. Sera samples are injected directly onto an Internal Surface Reverse Phase ISRP precolumn, which separates free from protein bound material. Non-protein bound material is passed through an analytical reverse phase column of separation of metabolites. With this method of analysis, significant species variation in both the rate of serum binding and metabolism of different TcCl(dioxime)3BR complexes can be demonstrated. The method allows for the prescreening of potential 99m-Tc radiopharmaceuticals prior to extensive animal testing

  17. Dark Blood Magnetic Resonance Lymphangiography Using Dual-Agent Relaxivity Contrast (DARC-MRL): A Novel Method Combining Gadolinium and Iron Contrast Agents.

    Science.gov (United States)

    Maki, Jeffrey H; Neligan, Peter C; Briller, Noah; Mitsumori, Lee M; Wilson, Gregory J

    2016-01-01

    The objective of this study was to develop and demonstrate a technique to eliminate venous enhancement in contrast-enhanced magnetic resonance lymphangiography through shortening T2(⁎) in the blood pool, thus allowing for a lymphatic-only map. Administration of the blood-pool iron agent ferumoxtyol in addition to intracutaneous gadolinium during contrast-enhanced magnetic resonance lymphangiography allows for suppression of vascular structures to achieve venous-free lymphatic mapping. PMID:26460054

  18. Synthesis of silver nanoparticles using Dioscorea bulbifera tuber extract and evaluation of its synergistic potential in combination with antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Ghosh S

    2012-02-01

    -positive bacteria. Beta-lactam (piperacillin and macrolide (erythromycin antibiotics showed a 3.6-fold and 3-fold increase, respectively, in combination with silver nanoparticles selectively against multidrug-resistant Acinetobacter baumannii. Notable synergy was seen between silver nanoparticles and chloramphenicol or vancomycin against Pseudomonas aeruginosa, and was supported by a 4.9-fold and 4.2-fold increase in zone diameter, respectively. Similarly, we found a maximum 11.8-fold increase in zone diameter of streptomycin when combined with silver nanoparticles against E. coli, providing strong evidence for the synergistic action of a combination of antibiotics and silver nanoparticles.Conclusion: This is the first report on the synthesis of silver nanoparticles using D. bulbifera tuber extract followed by an estimation of its synergistic potential for enhancement of the antibacterial activity of broad spectrum antimicrobial agents.Keywords: Dioscorea bulbifera tuber extract, silver nanoparticles, antimicrobial synergy

  19. Efficacy and safety of combining intra-articular methylprednisolone and anti-TNF agent to achieve prolonged remission in patients with recurrent inflammatory monoarthritis.

    LENUS (Irish Health Repository)

    Haroon, Muhammad

    2012-02-01

    OBJECTIVE: To control local inflammation, the role of intra-articular corticosteroid is well established; similarly, with time there are more reports on the experience of intra-articular anti-TNF agent for localized joint inflammation. The aim of this study was to assess the safety, local tolerability and clinical response after combining intra-articular administration of corticosteroids and anti-TNF agents for recurrent inflammatory monoarthritis. METHODS: Patients with recurrent monoarthritis of the knee were recruited from our inflammatory arthritis clinics. These patients required intra-articular corticosteroids every 8-12 weeks, with good short-term results. Five such consecutive patients were invited to partake in this study. Patients were maintained on their baseline immunosuppressive therapy. After aspiration of knee joint, the involved joint was injected with 80mg of methylprednisolone mixed with 5ml of lignocaine 1%; this was followed by the injection of an anti-TNF agent. RESULTS: In majority of our patients (three out of five), combining anti-TNF agent and methylprednisolone led to prolonged anti-inflammatory response, and these patients remain in remission to date (mean follow-up of 12 months). These responders were noted to be naive to anti-TNF therapy. Conversely, the remaining two patients were found to be on baseline systemic anti-TNF therapy, and both of them failed to respond either partly or completely. CONCLUSION: Combining intra-articular corticosteroid and anti-TNF agent has proved to be safe in our cohort of patients. We conclude that in particular subset of patients who suffer from recurrent inflammatory monoarthritis or oligoarthritis, combination therapy of intra-articular corticosteroids and anti-TNF agents appears attractive and promising.

  20. A novel single walled carbon nanotube (SWCNT) functionalization agent facilitating in vivo combined chemo/thermo therapy

    Science.gov (United States)

    Zhang, Liwen; Rong, Pengfei; Chen, Minglong; Gao, Shi; Zhu, Lei

    2015-10-01

    Carbon nanotubes (CNTs) have shown intriguing applications in biotechnological and biomedical fields due to their unique shape and properties. However, the fact that unmodified CNTs are prone to aggregation, stunts CNTs applications under physiological conditions. In this research, we found that as little as 1/5th the single walled carbon nanotube (SWCNT) weight of Evans Blue (EB) is capable of dispersing SWCNT as well as facilitating SWCNT functionalization. In view of the binding between EB and albumin, the yielding product (SWCNT/EB) demonstrated extreme stability for weeks under physiological conditions and it can be endowed with a therapeutic ability by simply mixing SWCNT/EB with an albumin based drug. Specifically, the formed SWCNT/EB/albumin/PTX nanocomplex exhibits strong near-infrared (NIR) absorbance, and can serve as an agent for chemo/thermal therapeutic purposes. Our in vivo result reveals that SWCNT/EB/albumin/PTX after being administered into the MDA-MB-435 tumor would effectively ablate the tumor by chemo and photothermal therapy. Such a combined treatment strategy provides remarkable therapeutic outcomes in restraining tumor growth compared to chemo or photothermal therapy alone. Overall, our strategy of dispersing SWCNTs by EB can be used as a platform for carrying other drugs or functional genes with the aid of albumin to treat diseases. The present study opens new opportunities in surface modification of SWCNTs for future clinical disease treatment.Carbon nanotubes (CNTs) have shown intriguing applications in biotechnological and biomedical fields due to their unique shape and properties. However, the fact that unmodified CNTs are prone to aggregation, stunts CNTs applications under physiological conditions. In this research, we found that as little as 1/5th the single walled carbon nanotube (SWCNT) weight of Evans Blue (EB) is capable of dispersing SWCNT as well as facilitating SWCNT functionalization. In view of the binding between EB and

  1. Two-dimensional separation of peptides using RP-RP-HPLC system with different pH in first and second separation dimensions.

    Science.gov (United States)

    Gilar, Martin; Olivova, Petra; Daly, Amy E; Gebler, John C

    2005-09-01

    Two-dimensional high performance liquid chromatography is a useful tool for proteome analysis, providing a greater peak capacity than single-dimensional LC. The most popular 2D-HPLC approach used today for proteomic research combines strong cation exchange and reversed-phase HPLC. We have evaluated an alternative mode for 2D-HPLC of peptides, employing reversed-phase columns in both separation dimensions. The orthogonality of 2D separation was investigated for selected types of RP stationary phases, ion-pairing agents and mobile phase pH. The pH appears to have the most significant impact on the RP-LC separation selectivity; the greatest orthogonality was achieved for the system with C18 columns using pH 10 in the first and pH 2.6 in the second LC dimension. Separation was performed in off-line mode with partial fraction evaporation. The achievable peak capacity in RP-RP-HPLC and overall performance compares favorably to SCX-RP-HPLC and holds promise for proteomic analysis. PMID:16224963

  2. HPLC: Early and Recent Perspectives.

    Science.gov (United States)

    Karger, Barry L.

    1997-01-01

    Provides a perspective on what it was like in the early days of high-performance liquid chromatography (HPLC) and several of the key developments. Focuses on the advances in HPLC generally, and more specifically for the biological sciences, that were necessary for the method to reach the preeminent stage of today. Contains 20 references. (JRH)

  3. Quantitative analysis of the anti-proliferative activity of combinations of selected iron-chelating agents and clinically used anti-neoplastic drugs.

    Directory of Open Access Journals (Sweden)

    Eliska Potuckova

    Full Text Available Recent studies have demonstrated that several chelators possess marked potential as potent anti-neoplastic drugs and as agents that can ameliorate some of the adverse effects associated with standard chemotherapy. Anti-cancer treatment employs combinations of several drugs that have different mechanisms of action. However, data regarding the potential interactions between iron chelators and established chemotherapeutics are lacking. Using estrogen receptor-positive MCF-7 breast cancer cells, we explored the combined anti-proliferative potential of four iron chelators, namely: desferrioxamine (DFO, salicylaldehyde isonicotinoyl hydrazone (SIH, (E-N'-[1-(2-hydroxy-5-nitrophenylethyliden] isonicotinoyl hydrazone (NHAPI, and di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT, plus six selected anti-neoplastic drugs. These six agents are used for breast cancer treatment and include: paclitaxel, 5-fluorouracil, doxorubicin, methotrexate, tamoxifen and 4-hydroperoxycyclophosphamide (an active metabolite of cyclophosphamide. Our quantitative chelator-drug analyses were designed according to the Chou-Talalay method for drug combination assessment. All combinations of these agents yielded concentration-dependent, anti-proliferative effects. The hydrophilic siderophore, DFO, imposed antagonism when used in combination with all six anti-tumor agents and this antagonistic effect increased with increasing dose. Conversely, synergistic interactions were observed with combinations of the lipophilic chelators, NHAPI or Dp44mT, with doxorubicin and also the combinations of SIH, NHAPI or Dp44mT with tamoxifen. The combination of Dp44mT with anti-neoplastic agents was further enhanced following formation of its redox-active iron and especially copper complexes. The most potent combinations of Dp44mT and NHAPI with tamoxifen were confirmed as synergistic using another estrogen receptor-expressing breast cancer cell line, T47D, but not estrogen receptor

  4. Quantitative analysis of the anti-proliferative activity of combinations of selected iron-chelating agents and clinically used anti-neoplastic drugs.

    Science.gov (United States)

    Potuckova, Eliska; Jansova, Hana; Machacek, Miloslav; Vavrova, Anna; Haskova, Pavlina; Tichotova, Lucie; Richardson, Vera; Kalinowski, Danuta S; Richardson, Des R; Simunek, Tomas

    2014-01-01

    Recent studies have demonstrated that several chelators possess marked potential as potent anti-neoplastic drugs and as agents that can ameliorate some of the adverse effects associated with standard chemotherapy. Anti-cancer treatment employs combinations of several drugs that have different mechanisms of action. However, data regarding the potential interactions between iron chelators and established chemotherapeutics are lacking. Using estrogen receptor-positive MCF-7 breast cancer cells, we explored the combined anti-proliferative potential of four iron chelators, namely: desferrioxamine (DFO), salicylaldehyde isonicotinoyl hydrazone (SIH), (E)-N'-[1-(2-hydroxy-5-nitrophenyl)ethyliden] isonicotinoyl hydrazone (NHAPI), and di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT), plus six selected anti-neoplastic drugs. These six agents are used for breast cancer treatment and include: paclitaxel, 5-fluorouracil, doxorubicin, methotrexate, tamoxifen and 4-hydroperoxycyclophosphamide (an active metabolite of cyclophosphamide). Our quantitative chelator-drug analyses were designed according to the Chou-Talalay method for drug combination assessment. All combinations of these agents yielded concentration-dependent, anti-proliferative effects. The hydrophilic siderophore, DFO, imposed antagonism when used in combination with all six anti-tumor agents and this antagonistic effect increased with increasing dose. Conversely, synergistic interactions were observed with combinations of the lipophilic chelators, NHAPI or Dp44mT, with doxorubicin and also the combinations of SIH, NHAPI or Dp44mT with tamoxifen. The combination of Dp44mT with anti-neoplastic agents was further enhanced following formation of its redox-active iron and especially copper complexes. The most potent combinations of Dp44mT and NHAPI with tamoxifen were confirmed as synergistic using another estrogen receptor-expressing breast cancer cell line, T47D, but not estrogen receptor-negative MDA

  5. A meta-analysis of combination therapy versus single-agent therapy in anthracycline- and taxane-pretreated metastatic breast cancer: results from nine randomized Phase III trials

    Science.gov (United States)

    Xu, Liang; Wu, Xiaobo; Hu, Chun; Zhang, Zhiying; Zhang, Le; Liang, Shujing; Xu, Yingchun; Zhang, Fengchun

    2016-01-01

    Nowadays, the philosophy of treating metastatic breast cancer (MBC) is slowly evolving. Especially for the anthracycline- and taxane-pretreated MBC patients, no standard therapy exists in this setting. Whether to choose doublet agents or single agent as salvage treatment remains fiercely debated. Thus, we conducted a meta-analysis to resolve this problem. Databases including PubMed, EMBASE, and Cochrane library were searched for Phase III randomized clinical trials (published before August 2015) comparing the efficacy and adverse effects between the combination therapy and single-agent therapy in anthracycline- and taxane-pretreated MBC patients. The primary end point was the overall survival (OS), and the secondary end points were the progression-free survival (PFS), overall response rate (ORR), and grade 3 or 4 toxicities. The pooled hazard ratio (HR) and pooled risk ratio (RR) were used to evaluate the efficacy. Analyses were also performed to estimate the side effects and safety of both groups. In all, nine eligible randomized clinical trials were included in this meta-analysis. Improvements were proven in the doublet agents group on OS (HR 0.90, 95% confidence interval [CI] 0.84–0.96, P=0.002), PFS (HR 0.81, 95% CI 0.76–0.88, P<0.001), and ORR (RR 1.72, 95% CI 1.34–2.21, P<0.001). Notably, subgroup analysis failed to favor the targeted agent-based combination in terms of OS (HR 1.08, 95% CI 0.89–1.31, P=0.365), PFS (HR 1.09, 95% CI 0.88–1.35, P=0.433), and ORR (RR 1.60, 95% CI 0.69–3.71, P=0.278) compared with single agent. In addition, although more hematological and gastrointestinal toxicities were observed in the doublet agents group, they were acceptable and manageable. Taken together, when compared with single-agent therapy, doublet agents should be considered a treatment option because of the superior efficacy and the manageable safety profile for the prior anthracycline- and taxane-treated MBC patients. PMID:27445497

  6. Competing intermolecular interactions of artemisinin-type agents and aspirin with membrane phospholipids: Combined model mass spectrometry and quantum-chemical study

    International Nuclear Information System (INIS)

    Highlights: • Competitive binding of artemisinin agents and aspirin with phospholipids is shown. • Complexation between the antimalarial drugs and aspirin molecules is also found. • Energetically favorable structures of the model complexes are identified by DFT. • Membranotropic activity of the studied drugs can be modified under joint usage. - Abstract: Study of intermolecular interactions of antimalarial artemisinin-type drugs and aspirin with membrane phospholipids is important in term of elucidation of the drugs activity modification under their joint usage. Combined experimental and computational study of the interaction of dihydroartemisinin, α-artemether, and artesunate with aspirin (ASP) and dipalmitoylphosphatidylcholine (DPPC) is performed by electrospray ionization (ESI) mass spectrometry and by DFT B3LYP/aug-cc-pVDZ methods. The results of the ESI investigation of systems containing artemisinin-type agent, ASP and DPPC, reveal a competition between the antimalarial agents and ASP for binding with DPPC molecules. The complexation between the antimalarial drugs and ASP is also found. Observed phenomena suggest that membranotropic activity of artemisin-type agents and aspirin is modified under their combined usage. To elucidate structure-energy characteristics of the non-covalent complexes studied the model DFT calculations are performed for dihydroartemisinin · ASP complex and complexes of the each drug with phosphatidylcholine head of DPPC in neutral and cationized forms

  7. Competing intermolecular interactions of artemisinin-type agents and aspirin with membrane phospholipids: Combined model mass spectrometry and quantum-chemical study

    Energy Technology Data Exchange (ETDEWEB)

    Pashynska, Vlada, E-mail: vlada@vl.kharkov.ua [B.Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, Lenin Ave., 47, 61103 Kharkov (Ukraine); Stepanian, Stepan [B.Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, Lenin Ave., 47, 61103 Kharkov (Ukraine); Gömöry, Agnes; Vekey, Karoly [Institute of Organic Chemistry of Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Magyar tudosok korutja, 2, Budapest H-1117 (Hungary); Adamowicz, Ludwik [University of Arizona, Department of Chemistry and Biochemistry, Tucson, AZ 85721 (United States)

    2015-07-09

    Highlights: • Competitive binding of artemisinin agents and aspirin with phospholipids is shown. • Complexation between the antimalarial drugs and aspirin molecules is also found. • Energetically favorable structures of the model complexes are identified by DFT. • Membranotropic activity of the studied drugs can be modified under joint usage. - Abstract: Study of intermolecular interactions of antimalarial artemisinin-type drugs and aspirin with membrane phospholipids is important in term of elucidation of the drugs activity modification under their joint usage. Combined experimental and computational study of the interaction of dihydroartemisinin, α-artemether, and artesunate with aspirin (ASP) and dipalmitoylphosphatidylcholine (DPPC) is performed by electrospray ionization (ESI) mass spectrometry and by DFT B3LYP/aug-cc-pVDZ methods. The results of the ESI investigation of systems containing artemisinin-type agent, ASP and DPPC, reveal a competition between the antimalarial agents and ASP for binding with DPPC molecules. The complexation between the antimalarial drugs and ASP is also found. Observed phenomena suggest that membranotropic activity of artemisin-type agents and aspirin is modified under their combined usage. To elucidate structure-energy characteristics of the non-covalent complexes studied the model DFT calculations are performed for dihydroartemisinin · ASP complex and complexes of the each drug with phosphatidylcholine head of DPPC in neutral and cationized forms.

  8. Simultaneous determination of triclosan and triclocarban in environmental water samples by liquid extration combined with HPLC - ESI - MS%液液萃取-HPLC-ESI-MS法同步测定环境水样中的三氯卡班和三氯生

    Institute of Scientific and Technical Information of China (English)

    孙静; 赵汝松; 王霞; 王晨; 王西奎

    2011-01-01

    建立了LLE-HPLC-ESI-MS同步测定环境水样中三氯卡班(TCC)和三氯生(TCS)的分析方法.用40 mL二氯甲烷液-液萃取400 mL水样两次,合并萃取液后旋蒸至2-3 mL,在室温下用柔和的N2吹干,1 mL甲醇复溶,进行HPLC-ESI-MS检测.考察了方法的线性参数、最低检出限以及回收率.该方法的检出限分别为TCC 5 ng/L,TCS 15 ng/L,在10-1000 ng/L和50-1000 ng/L范围内有良好的线性关系,相对标准偏差(RSD)分别为TCC 3.4%,TCS 4.7%.该方法可应用于实际环境水样的检测.

  9. 中草药凉茶中甜味剂的液相色谱测定法%Determination of sweetening agents in Chinese medicinal herb tea by HPLC

    Institute of Scientific and Technical Information of China (English)

    罗海英; 杨毅兰; 李荔; 陈亚精

    2013-01-01

    [Objective] To establish a new monitoring method for simultaneous determination of the content of 3 sweeteners contained in Chinese medicinal herb tea by applying HPLC. [Methods]The sample was diluted by mobile phase which was 20 mmoL sodium dihydrogen phosphate dihydrate and acetonitrile; gradient elution was adopted on the sample. [Results] The 3 sweeteners (Acesul-fame-K , Saccharin Sodium , Aspartame) could be completely separated. With the linearity range within 8-200 μg/ml, the recovery rate was between 90.5% -107.4% , and RSD was under 1.81% ( n = 6). The minimum detection limits were 2. 46 × 10 -4, 2. 41 × 10 -4, 7.09 × 10 -4 respectively, while the minimum limits of quantitation were 2.46 × 10 -3, 1. 20 × 10 -3, 3. 55 × 10 -3, respectively. [ Conclusion ] This methodology can satisfy the requirements of simultaneously determining Acesulfame K, Sodium Saccharin and Aspartame in herbal tea. It is can be extended in other drugs and food inspection.%目的 建立一种应用高效液相色谱法同时测定中草药凉茶中3种甜味剂含量的监测方法.方法 样品经流动相稀释,以20 mmol/L磷酸二氢钠与乙腈为流动相,进行梯度洗脱.结果 可将3种甜味剂安赛蜜、糖精钠、阿斯巴甜完全分离,在8~200 μg/ml线性范围内(r均大于0.999 9),回收率在90.5% ~ 107.4%之间,RSD在1.81%以下(n=6).最低检出限分别为4.93×10-4、2.4×10-4和7.09×10-4mg/kg,最低定量限分别为2.46×10.3、1.20×10-3和3.55×10-3mg/kg.结论 该方法能满足中草药凉茶中同时测定安赛蜜、糖精钠、阿斯巴甜的要求,该方法可推广至药物及其他食品检验.

  10. Prevention of enzymatic browning of yacon flour by the combined use of anti-browning agents and the study of its chemical composition

    OpenAIRE

    Oscar Romero Lopes Rodrigues; Eduardo Ramirez Asquieri; Daniela Castilho Orsi

    2014-01-01

    Yacon roots present functional properties because of the high levels of fructooligosaccharides (FOS), which are considered as prebiotic fibers. In addition, yacon roots are rich in phenolic compounds. During the processing of yacon, the freshly cut surface undergoes rapid enzymatic browning. Control of enzymatic browning during processing is very important to preserve the appearance of yacon flour. In this study, it was evaluated the combined effect of anti-browning agents (ascorbic acid, cit...

  11. Quantitative Analysis of the Anti-Proliferative Activity of Combinations of Selected Iron-Chelating Agents and Clinically Used Anti-Neoplastic Drugs

    OpenAIRE

    Eliska Potuckova; Hana Jansova; Miloslav Machacek; Anna Vavrova; Pavlina Haskova; Lucie Tichotova; Vera Richardson; Kalinowski, Danuta S.; Richardson, Des R.; Tomas Simunek

    2014-01-01

    Recent studies have demonstrated that several chelators possess marked potential as potent anti-neoplastic drugs and as agents that can ameliorate some of the adverse effects associated with standard chemotherapy. Anti-cancer treatment employs combinations of several drugs that have different mechanisms of action. However, data regarding the potential interactions between iron chelators and established chemotherapeutics are lacking. Using estrogen receptor-positive MCF-7 breast cancer cells, ...

  12. Effects of Coptis extract combined with chemotherapeutic agents on ROS production, multidrug resistance, and cell growth in A549 human lung cancer cells

    Directory of Open Access Journals (Sweden)

    He Chengwei

    2012-04-01

    Full Text Available Abstract Background Non–small cell lung cancer is associated with high expression of multidrug resistance (MDR proteins and low production of reactive oxygen species (ROS. Coptis extract (COP, a Chinese medicinal herb, and its major constituent, berberine (BER, have anticancer properties. This study aims to investigate the effects of COP and BER combined with chemotherapeutic agents, including fluorouracil (5-FU, camptothecin (CPT, and paclitaxel (TAX, on cell proliferation, ROS production, and MDR in A549 human non-small cell lung cancer cells. Methods A549 cells were treated with different doses of COP and BER, combined with 5-FU, CPT, and TAX. Cell viability was measured by an XTT (2,3-bis-(2-methoxy-4- nitro-5-sulfophenyl-2 H-tetrazolium-5-carboxanilide assay. Intracellular ROS levels were determined by measuring the oxidative conversion of cell permeable 2′,7′-dichlorofluorescein diacetate to fluorescent dichlorofluorescein. MDR of A549 cells was assessed by rhodamine 123 retention assay. Results Both COP and BER significantly inhibited A549 cell growth in a dose-dependent manner. Combinations of COP or BER with chemotherapeutic agents (5-FU, CPT, and TAX exhibited a stronger inhibitory effect on A549 cell growth. In addition, COP and BER increased ROS production and reduced MDR in A549 cells. Conclusion As potential adjuvants to chemotherapy for non–small cell lung cancer, COP and BER increase ROS production, reduce MDR, and enhance the inhibitory effects of chemotherapeutic agents on A549 cell growth.

  13. The efficacy and tolerability of the slow-acting combined agent glucosamine and chondroitin sulfate in gonarthrosis patients tacking no nonsteroidal anti-inflammatory drugs

    OpenAIRE

    A P Rebrov; Romanova, I.A.; I. Z. Gaydukova

    2015-01-01

    Objective: to evaluate the efficacy and tolerability of the combined symptomatic slow-acting combined agent Theraflex in gonarthrosis patients untreated with nonsteroidal antiinflammatory drugs (NSAIDs).Patients and methods. The investigation enrolled 84 patients (78 women and 6 men) aged 55.23±7.36 years with knee arthritis lasting 6.2±0.98 years who were blindly randomized into 2 groups. A study group took Theraflex (chondroitin sulfate 400 mg and glucosamine sulfate 500 mg) with or without...

  14. Evaluation of antifungal activity of carbonate and bicarbonate salts alone or in combination with biocontrol agents in control of citrus green mold.

    Science.gov (United States)

    Zamani, M; Sharifi Tehrani, A; Ali Abadi, A Alizadeh

    2007-01-01

    The aim of this research was to determine if the attacks of green mold on orange could be reduced by edible salts alone or in combination with biocontrol agent. For this purpose toxicity to Pantoea digitatum and practical use of sodium carbonate (SC), sodium bicarbonate (SBC) and potassium carbonate, and potassium bicarbonate alone or in combination with antagonistic bacteria (Pseudomonas fluorescens isolate PN, Bacillus subtilis isolate VHN, Pantoea agglomerans isolate CA) to control green mold were determined. All were fungistatic. SC and SBC were equal and superior to the other salts for control of green mold on oranges inoculated 6h before treatment and were chosen for subsequent trails under cold storage conditions. The biocontrol agents were found completely tolerant to 3% sodium bicarbonate and sodium carbonate at room temperature; although their culturability was reduced by > 1000-fold after 60 min in 1% other salt solutions. Satisfactory results were also obtained with the combined treatment for control of green mold. A significant increase in biocontrol activity of all isolate was observed when combined with sodium carbonate and sodium bicarbonate. The treatments comprising CA combined with SB was as effective as fungicide treatment. Thus, use of sodium bicarbonate treatment at 3% followed by the antagonist P. agglomerans CA could be an alternative to chemical fungicides for control of green mold on oranges. PMID:18396809

  15. A meta-analysis of combination therapy versus single-agent therapy in anthracycline- and taxane-pretreated metastatic breast cancer: results from nine randomized Phase III trials

    Directory of Open Access Journals (Sweden)

    Xu L

    2016-07-01

    Full Text Available Liang Xu,1,2,* Xiaobo Wu,3,* Chun Hu,1,2 Zhiying Zhang,4 Le Zhang,1,2 Shujing Liang,1,2 Yingchun Xu,5 Fengchun Zhang1,2 1Department of Oncology, Suzhou Kowloon Hospital, Shanghai Jiaotong University School of Medicine, Suzhou, 2Department of Oncology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 3Prevention and Cure Center of Breast Disease, Third Hospital of Nanchang, Nanchang, 4Graduate School, Xuzhou Medical College, Xuzhou, 5Department of Oncology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Nowadays, the philosophy of treating metastatic breast cancer (MBC is slowly evolving. Especially for the anthracycline- and taxane-pretreated MBC patients, no standard therapy exists in this setting. Whether to choose doublet agents or single agent as salvage treatment remains fiercely debated. Thus, we conducted a meta-analysis to resolve this problem. Databases including PubMed, EMBASE, and Cochrane library were searched for Phase III randomized clinical trials (published before August 2015 comparing the efficacy and adverse effects between the combination therapy and single-agent therapy in anthracycline- and taxane-pretreated MBC patients. The primary end point was the overall survival (OS, and the secondary end points were the progression-free survival (PFS, overall response rate (ORR, and grade 3 or 4 toxicities. The pooled hazard ratio (HR and pooled risk ratio (RR were used to evaluate the efficacy. Analyses were also performed to estimate the side effects and safety of both groups. In all, nine eligible randomized clinical trials were included in this meta-analysis. Improvements were proven in the doublet agents group on OS (HR 0.90, 95% confidence interval [CI] 0.84–0.96, P=0.002, PFS (HR 0.81, 95% CI 0.76–0.88, P<0.001, and ORR (RR 1.72, 95% CI 1.34–2.21, P<0.001. Notably, subgroup analysis

  16. Trabectedin as a single agent and in combination with pegylated liposomal doxorubicin – activity against ovarian cancer cells

    OpenAIRE

    Marczak, Agnieszka; Denel, Marta

    2014-01-01

    Over 225 000 new cases of ovarian cancer are diagnosed each year. Symptoms are often vague, so most cases are detected when the disease is at an advanced stage. There is a need to find new drugs which will be able to treat ovarian cancer effectively. One of the most promising antineoplastic agents is trabectedin (Yondelis), derived from the marine tunicate Ecteinascidia turbinata, approved by the European Union in July 2007 for the treatment of soft-tissue sarcomas. This drug shows a mechanis...

  17. Postcolumn reaction detectors for HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Frei, R.W.; Jansen, H.; Brinkman, U.A.T.

    1985-12-01

    Currently, the best and most reliable HPLC (high-performance liquid chromatography) detectors are UV-VIS absorbance, fluorescence, and electrochemical detectors. It is attractive to try to expand their range of application by using suitable chemical derivatization techniques to convert the analytes of interest with their originally poor detection properties into compounds that can be detected with high sensitivity with these detectors. Besides an improvement of the detection properties, the chemical reaction can also enhance the selectivity of the total analytical method. The derivatization can be carried out either prior to the HPLC separation or by doing the reaction in an on-line postcolumn mode. Comparative advantages and disadvantages of these two approaches have been discussed previously. This paper will discuss on-line postcolumn derivatization. A general scheme of an HPLC system equipped with an on-line postcolumn reaction detector is given. 40 references, 6 figures, 2 tables.

  18. A sensitive and practical RP-HPLC-FLD for determination of the low neuroactive amino acid levels in body fluids and its application in depression.

    Science.gov (United States)

    Wu, Juan-Li; Yu, Si-Yang; Wu, Shi-Hua; Bao, Ai-Min

    2016-03-11

    Ion-exchange high performance liquid chromatography (HPLC) generally fails as a method to determine low levels of free amino acids (AAs) in body fluids. Here we present a modified reversed-phase HPLC (RP-HPLC) protocol for the determination of AAs in body fluids and its application in mood disorder patients. We improved a previous research protocol by modifying i) sample preparation, including deproteination, ii) derivitization, including derivating agent and condition, and iii) sample separation, which is mainly determined by the pH value, the components and the additives of the mobile phases. The combination of these modifications, together with fluorescence detection (FLD), allows sensitive and practical determination of free AA levels in body fluids of depressive patients. This protocol was validated by determining the postmortem cerebrospinal fluid (CSF) glutamic acid (Glu) and γ-aminobutyric acid (GABA) levels of 8 major depressive disorder (MDD) patients, 9 bipolar disorder (BD) patients, and 19 well-matched controls, while also testing the plasma and CSF AA levels of living MDD patients. CSF Glu and GABA levels were both significantly decreased in MDD but not in BD patients. The data indicate that this RP-HPLC-FLD protocol is applicable for detection of low levels of neuroactive AAs in body fluids, as well as for routine clinical applications. PMID:26808642

  19. Enhanced vesicular stomatitis virus (VSVΔ51 targeting of head and neck cancer in combination with radiation therapy or ZD6126 vascular disrupting agent

    Directory of Open Access Journals (Sweden)

    Alajez Nehad M

    2012-06-01

    Full Text Available Abstract Background Head and neck squamous cell carcinoma (HNSCC is the 5th most common cancer worldwide. Locally advanced HNSCC are treated with either radiation or chemo-radiotherapy, but still associated with high mortality rate, underscoring the need to develop novel therapies. Oncolytic viruses have been garnering increasing interest as anti-cancer agents due to their preferential killing of transformed cells. In this study, we evaluated the therapeutic potential of mutant vesicular stomatitis virus (VSVΔ51 against the human hypopharyngeal FaDu tumour model in vitro and in vivo. Results Our data demonstrated high toxicity of the virus against FaDu cells in vitro, which was associated with induction of apoptosis. In vivo, systemic injection of 1 × 109 pfu had minimal effect on tumour growth; however, when combined with two doses of ionizing radiation (IR; 5 Gy each or a single injection of the vascular disrupting agent (ZD6126, the virus exhibited profound suppression of tumour growth, which translated to a prolonged survival in the treated mice. Concordantly, VSVΔ51 combined with ZD6126 led to a significant increase in viral replication in these tumours. Conclusions Our data suggest that the combinations of VSVΔ51 with either IR or ZD6126 are potentially novel therapeutic opportunities for HNSCC.

  20. Induction of apoptosis in osteogenic sarcoma cells by combination of tumor necrosis factor-related apoptosis inducing ligand and chemotherapeutic agents

    Institute of Scientific and Technical Information of China (English)

    SUN Jie; FU Zhi-min; FANG Chang-qing; LI Jian-hua

    2007-01-01

    Background Osteosarcoma is one of the most common primary malignant tumors of bone with poor prognosis.TNF-related apoptosis inducing ligand (TRAIL) is a member of the tumor necrosis factor (TNF) cytokine family. TRAIL induces apoptosis in various tumor cell lines but is not found to be cytotoxic to many normal cell types in vitro. We investigated the cytotoxic activity of TRAIL and chemotherapeutic agents, including methotrexate (MTX), doxorubicin(DOX) and cisplatin (CDDP), on established osteosarcoma cell line-OS-732.Methods OS-732 cells were incubated with chemotherapeutic agents MTX,DOX and CDDP at various peak plasma concentrations(PPC), 0.1PPC,1PPC and 10PPC, alone or with 100 ng/ml of TRAIL for 24 hours or 48 hours. MTT was used to evaluate the cytotoxic activity of different agents on OS-732. The apoptosis proportion was assayed by flow cytometry. Cellular morphologic changes were observed by phase contrast microscope, scan electron microscope, and transmission electron microscope.Results The inhibitory rate was (24.438±3.414)% with TRAIL of 100 ng/ml for 24 hours. The cells were responsive to DOX and CDDP with a dose-effect relationship (P<0.05). In OS-732 cells, DOX and CDDP cooperated synergistically with TRAIL when incubated the cells with them for 24 hours (the combined inhibitory rate is (58.360±2.146)% and (54.101 ±2.721)%, respectively). TRAIL alone or drugs alone induced the apoptosis rate was less than 25% (P<0.05).However, the combination of TRAIL and MTX did not present synergistic effects on OS-732 cells (P>0.05, compared with TRAIL alone).Conclusions Osteosarcoma OS-732 cells were not responsive to TRAIL-induced apoptosis. DOX and CDDP sensitize osteosarcoma OS-732 cells to TRAIL-induced apoptosis. The combination of TRAIL and MTX presented no synergistic effects on killing OS-732 cells.

  1. Usefulness of tirapazamine as a combined agent in chemoradiation and thermo-chemoradiation therapy at mild temperatures. Reference to the effect on intratumor quiescent cells

    International Nuclear Information System (INIS)

    C3H/He mice bearing SCC VII tumors received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received one of six different DNA-damaging agents with or without mild temperature hyperthermia (40 deg C, 30 min, MTH). These agents were adriamycin (ADM), mitomycin C (MMC), cyclophosphamide (CPA), bleomycin (BLM), cisplatin (CDDP), and tirapazamine (TPZ). After the drug treatment, the tumor-bearing mice were irradiated with a series of doses of γ-rays. Immediately after irradiation, the tumors were excised, minced and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (=quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P+Q) tumor cells was determined from the tumors that had not been pretreated with BrdU. MTH significantly increased the MN frequency of total cells in tumors irradiated with γ-rays combined with CPA, BLM, CDDP or TPZ, and that of Q cells in tumors irradiated with γ-rays combined with BLM or TPZ. The sensitivity difference in the MN frequency between total and Q tumor cells was significantly decreased by the combination with TPZ. TPZ combined with radiotherapy and TPZ combined with thermo-radiotherapy at mild temperatures appear to be promising modalities for sensitizing tumor cells in vivo, including Q tumor cells. (author)

  2. Anti-cancer Effects of Novel Flavonoid Vicenin-2 as a Single Agent and in Synergistic Combination with Docetaxel in Prostate Cancer

    OpenAIRE

    Nagaprashantha, Lokesh Dalasanur; Vatsyayan, Rit; Singhal, Jyotsana; Fast, Spence; Roby, Rhonda; Awasthi, Sanjay; SINGHAL, SHARAD S.

    2011-01-01

    The present study was conducted to determine the efficacy of novel flavonoid vicenin-2 (VCN-2), an active constituent of the medicinal herb Ocimum Sanctum Linn or Tulsi, as a single agent and in combination with docetaxel (DTL) in carcinoma of prostate (CaP). VCN-2 effectively induced anti-proliferative, anti-angiogenic and pro-apoptotic effect in CaP cells (PC-3, DU-145 and LNCaP) irrespective of their androgen responsiveness or p53 status. VCN-2 inhibited EGFR/Akt/mTOR/ p70S6K pathway along...

  3. Amino acid PET tracers are reliable markers of treatment responses to single-agent or combination therapies including temozolomide, interferon-β, and/or bevacizumab for glioblastoma

    International Nuclear Information System (INIS)

    Introduction: We examined whether the amino acid PET tracers, trans-1-amino-3-18F-fluorocyclobutanecarboxylic acid (anti-18F-FACBC) and 11C-methyl-L-methionine (11C-Met), are suitable for detecting early responses to combination therapies including temozolomide (TMZ), interferon-β (IFN), and bevacizumab (Bev) in glioblastoma. Methods: Human glioblastoma U87MG (U87) cells were incubated with low dose TMZ to induce chemoresistance. Both trans-1-amino-3-fluoro-1-14C-cyclobutanecarboxylic acid (anti-14C-FACBC) and 3H-methyl-L-methionine (3H-Met) uptake were quantified using triple-label accumulation assays to examine the relationship between tracer uptake and proliferation (3H-thymidine (TdR) accumulation) in vitro. U87 and U87R (TMZ-resistant subculture) cells were inoculated into the right and left basal ganglia, respectively, of F344/N-rnu rats. The efficacy of single-agent (TMZ, Bev) and combination therapy (TMZ/IFN, TMZ/Bev, TMZ/IFN/Bev) was examined in orthotopic gliomas using MRI, Evans blue extravasation, anti-14C-FACBC, and 3H-Met autoradiography, and MIB-1 immunostaining. Results: TMZ treatment decreased 3H-TdR accumulation and the volume distribution of anti-14C-FACBC and 3H-Met in U87 but not U87R cells. TMZ/IFN combination therapy significantly decreased these parameters in U87R cells; however, Bev had no additional effect in vitro. In vivo, U87R-derived gliomas were observed as equivocal tumors on MRI and T2-high intensity lesions. Bev treatment, either alone or in combination, markedly decreased U87 enhancing lesions. By contrast, autoradiographic images using anti-14C-FACBC and 3H-Met clearly delineated tumor extent, which spread widely beyond T2-high intensity lesions and enhancing lesions. TMZ therapy significantly decreased tracer accumulation and proliferation of U87- but not U87R-derived tumors. TMZ/IFN combination treatment significantly decreased these parameters in U87R tumors, which were further reduced (in both tumor types) by Bev addition

  4. The design and synthesis of novel heterodinuclear complexes combining a DNA-cleaving agent and a DNA-targeting moiety

    NARCIS (Netherlands)

    Hoog, Paul de

    2008-01-01

    Cancer is a leading cause of death worldwide. Nowadays, the treatment of cancer by chemotherapy can consist of a combination of antitumor drugs. Nevertheless, chemotherapy is accompanied by serious side effects and intrinsic and acquired resistance to the drugs. This thesis describes the design and

  5. A hybrid FIA/HPLC system incorporating monolithic column chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Adcock, Jacqui L. [School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217 (Australia); Francis, Paul S. [School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217 (Australia)], E-mail: psf@deakin.edu.au; Agg, Kent M. [School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217 (Australia); Marshall, Graham D. [GlobalFIA, Fox Island, WA 98333 (United States); Barnett, Neil W. [School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217 (Australia)

    2007-09-26

    We have combined the generation of solvent gradients using milliGAT pumps, chromatographic separations with monolithic columns and chemiluminescence detection in an instrument manifold that approaches the automation and separation efficiency of HPLC, whilst maintaining the positive attributes of flow injection analysis (FIA), such as manifold versatility, speed of analysis and portability. As preliminary demonstrations of this hybrid FIA/HPLC system, we have determined six opiate alkaloids (morphine, pseudomorphine, codeine, oripavine, ethylmorphine and thebaine) and four biogenic amines (vanilmandelic acid, serotonin, 5-hydroxyindole-3-acetic acid and homovanillic acid) in human urine, using tris(2,2'-bipyridyl)ruthenium(III) and acidic potassium permanganate chemiluminescence detection.

  6. A hybrid FIA/HPLC system incorporating monolithic column chromatography

    International Nuclear Information System (INIS)

    We have combined the generation of solvent gradients using milliGAT pumps, chromatographic separations with monolithic columns and chemiluminescence detection in an instrument manifold that approaches the automation and separation efficiency of HPLC, whilst maintaining the positive attributes of flow injection analysis (FIA), such as manifold versatility, speed of analysis and portability. As preliminary demonstrations of this hybrid FIA/HPLC system, we have determined six opiate alkaloids (morphine, pseudomorphine, codeine, oripavine, ethylmorphine and thebaine) and four biogenic amines (vanilmandelic acid, serotonin, 5-hydroxyindole-3-acetic acid and homovanillic acid) in human urine, using tris(2,2'-bipyridyl)ruthenium(III) and acidic potassium permanganate chemiluminescence detection

  7. Effect of MR contrast agents on quantitative accuracy of PET in combined whole-body PET/MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lois, Cristina [University of Santiago de Compostela, Department of Particle Physics, Santiago de Compostela (Spain); Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela (Spain); Imaging Science Institute, Tuebingen (Germany); Bezrukov, Ilja [Eberhard Karls University, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens Foundation, Department of Preclinical Imaging and Radiopharmacy, Tuebingen (Germany); Max Plank Institute for Intelligent Systems, Department of Empirical Inference, Tuebingen (Germany); Schmidt, Holger [Eberhard Karls University, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens Foundation, Department of Preclinical Imaging and Radiopharmacy, Tuebingen (Germany); Eberhard Karls University, Diagnostic and Interventional Radiology, Department of Radiology, Tuebingen (Germany); Schwenzer, Nina; Werner, Matthias K. [Eberhard Karls University, Diagnostic and Interventional Radiology, Department of Radiology, Tuebingen (Germany); Kupferschlaeger, Juergen [Eberhard Karls University, Nuclear Medicine, Department of Radiology, Tuebingen (Germany); Beyer, Thomas [Imaging Science Institute, Tuebingen (Germany); cmi-experts GmbH, Zuerich (Switzerland)

    2012-11-15

    Clinical PET/MR acquisition protocols entail the use of MR contrast agents (MRCA) that could potentially affect PET quantification following MR-based attenuation correction (AC). We assessed the effect of oral and intravenous (IV) MRCA on PET quantification in PET/MR imaging. We employed two MRCA: Lumirem {sup registered} (oral) and Gadovist {sup registered} (IV). First, we determined their reference PET attenuation values using a PET transmission scan (ECAT-EXACT HR+, Siemens) and a CT scan (PET/CT Biograph 16 HI-REZ, Siemens). Second, we evaluated the attenuation of PET signals in the presence of MRCA. Phantoms were filled with clinically relevant concentrations of MRCA in a background of water and {sup 18}F-fluoride, and imaged using a PET/CT scanner (Biograph 16 HI-REZ, Siemens) and a PET/MR scanner (Biograph mMR, Siemens). Third, we investigated the effect of clinically relevant volumes of MRCA on MR-based AC using human pilot data: a patient study employing Gadovist {sup registered} (IV) and a volunteer study employing two different oral MRCA (Lumirem {sup registered} and pineapple juice). MR-based attenuation maps were calculated following Dixon-based fat-water segmentation and an external atlas-based and pattern recognition (AT and PR) algorithm. IV and oral MRCA in clinically relevant concentrations were found to have PET attenuation values similar to those of water. The phantom experiments showed that under clinical conditions IV and oral MRCA did not yield additional attenuation of PET emission signals. Patient scans showed that PET attenuation maps are not biased after the administration of IV MRCA but may be biased, however, after ingestion of iron oxide-based oral MRCA when segmentation-based AC algorithms are used. Alternative AC algorithms, such as AT and PR, or alternative oral contrast agents, such as pineapple juice, can yield unbiased attenuation maps. In clinical PET/MR scenarios MRCA are not expected to lead to markedly increased attenuation

  8. Effect of MR contrast agents on quantitative accuracy of PET in combined whole-body PET/MR imaging

    International Nuclear Information System (INIS)

    Clinical PET/MR acquisition protocols entail the use of MR contrast agents (MRCA) that could potentially affect PET quantification following MR-based attenuation correction (AC). We assessed the effect of oral and intravenous (IV) MRCA on PET quantification in PET/MR imaging. We employed two MRCA: Lumirem registered (oral) and Gadovist registered (IV). First, we determined their reference PET attenuation values using a PET transmission scan (ECAT-EXACT HR+, Siemens) and a CT scan (PET/CT Biograph 16 HI-REZ, Siemens). Second, we evaluated the attenuation of PET signals in the presence of MRCA. Phantoms were filled with clinically relevant concentrations of MRCA in a background of water and 18F-fluoride, and imaged using a PET/CT scanner (Biograph 16 HI-REZ, Siemens) and a PET/MR scanner (Biograph mMR, Siemens). Third, we investigated the effect of clinically relevant volumes of MRCA on MR-based AC using human pilot data: a patient study employing Gadovist registered (IV) and a volunteer study employing two different oral MRCA (Lumirem registered and pineapple juice). MR-based attenuation maps were calculated following Dixon-based fat-water segmentation and an external atlas-based and pattern recognition (AT and PR) algorithm. IV and oral MRCA in clinically relevant concentrations were found to have PET attenuation values similar to those of water. The phantom experiments showed that under clinical conditions IV and oral MRCA did not yield additional attenuation of PET emission signals. Patient scans showed that PET attenuation maps are not biased after the administration of IV MRCA but may be biased, however, after ingestion of iron oxide-based oral MRCA when segmentation-based AC algorithms are used. Alternative AC algorithms, such as AT and PR, or alternative oral contrast agents, such as pineapple juice, can yield unbiased attenuation maps. In clinical PET/MR scenarios MRCA are not expected to lead to markedly increased attenuation of the PET emission signals. MR

  9. Efficacy and safety of travoprost alone or in combination with other agents for glaucoma and ocular hypertension: patient considerations

    Directory of Open Access Journals (Sweden)

    Emilio Rintaro Suzuki Jr

    2010-10-01

    Full Text Available Emilio Rintaro Suzuki Jr, Cibele Lima Belico SuzukiInstituto de Olhos Pampulha, Belo, Horizonte, Minas Gerais, BrazilAbstract: Travoprost is a prostaglandin analog used in the management of glaucoma and ocular hypertension for reducing intraocular pressure (IOP. The IOP-lowering efficacy of travoprost has been shown to be similar to that of other prostaglandins, including latanoprost and bimatoprost. When compared with fixed combinations of timolol and either latanoprost or dorzolamide, travoprost alone can reduce mean IOP in a similar or superior manner. Concomitant therapy of travoprost and timolol can reach even greater IOP reductions than fixed combinations at some time points, but with no difference in the early morning, when IOP is usually higher. In addition, the long duration of action of travoprost can also provide better control of IOP fluctuation, probably due to its stronger prostaglandin F receptor mechanism. The side effects of travoprost do not represent a risk to the vision or health of the patient. The proven efficacy and safety combined with convenient once-daily dosing for travoprost increases patient compliance with treatment for glaucoma.Keywords: travoprost, prostaglandin, glaucoma

  10. Quantitative analysis of citric acid/sodium hypophosphite modified cotton by HPLC and conductometric titration.

    Science.gov (United States)

    Ye, Tao; Wang, Bijia; Liu, Jian; Chen, Jiangang; Yang, Yiqi

    2015-05-01

    Isocratic HPLC was used in conjunction with conductometric titration to quantitatively examine the modification of cotton cellulose by citric acid (CA)/sodium hypophosphite (SHP). CA/SHP had been extensively used as a green crosslinking agent for enhancement of cellulose and other carbohydrate polymers without in-depth understanding of the mechanisms. The current study investigated all identifiable secondary polycarboxylic acids from CA decomposition in the CA/SHP-cellulose system under various curing conditions. It was found that CA decomposition was more sensitive to temperature compared with the desirable esterification reaction. Two crosslinking mechanisms, namely ester crosslinking and SHP crosslinking were responsible for the observed improvement in crease resistance of CA/SHP treated cotton fabrics. An oligomer of citraconic acid (CCA) and/or itaconic acid (IA) was identified as a possible contributor to fabric yellowing. Finally, the crease resistance of fabrics correlated strongly with CA preservation in polyol-added CA/SHP crosslinking systems. The dosage of polyol should be held below an inflexion point to keep the undesirable competition against cellulose minimum. The combination of HPLC and conductometric titration was demonstrated to be useful in studying the CA/SHP-cellulose crosslinking system. The findings have implications for better application of CA/SHP in polysaccharide modifications in general. PMID:25659676

  11. Combination Approach of YSA Peptide Anchored Docetaxel Stealth Liposomes with Oral Antifibrotic Agent for the Treatment of Lung Cancer.

    Science.gov (United States)

    Patel, Ketan; Doddapaneni, Ravi; Sekar, Vasanthakumar; Chowdhury, Nusrat; Singh, Mandip

    2016-06-01

    Therapeutic efficacy of nanocarriers can be amplified by active targeting and overcoming the extracellular matrix associated barriers of tumors. The aim of the present study was to investigate the effect of oral antifibrotic agent (telmisartan) on tumor uptake and anticancer efficacy of EphA2 receptor targeted liposomes. Docetaxel loaded PEGylated liposomes (DPL) functionalized with nickel chelated phospholipid were prepared using a modified hydration method. DPL were incubated with various concentrations of histidine tagged EphA2 receptor specific peptide (YSA) to optimize particle size, zeta potential, and percentage YSA binding. Cellular uptake studies using various endocytosis blockers revealed that a caveolae dependent pathway was the major route for internalization of YSA anchored liposomes of docetaxel (YDPL) in A549 lung cancer cell line. Hydrodynamic diameter and zeta potential of optimized YDPL were 157.3 ± 11.8 nm and -3.64 mV, respectively. Orthotopic lung tumor xenograft (A549) bearing athymic nude mice treated with oral telmisartan (5 mg/kg) for 2 days showed significantly (p cancer. PMID:27070720

  12. Contrast agent and radiation dose reduction in abdominal CT by a combination of low tube voltage and advanced image reconstruction algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Buls, Nico; Gompel, Gert van; Nieboer, Koenraad; Willekens, Inneke; Mey, Johan de [Universitair Ziekenhuis Brussel (UZ Brussel), Department of Radiology, Brussels (Belgium); Vrije Universiteit Brussel (VUB), Research group LABO, Brussel (Belgium); Cauteren, Toon van [Vrije Universiteit Brussel (VUB), Research group LABO, Brussel (Belgium); Verfaillie, Guy [Universitair Ziekenhuis Brussel (UZ Brussel), Department of Radiology, Brussels (Belgium); Evans, Paul; Macholl, Sven; Newton, Ben [GE Healthcare, Department of Medical Diagnostics, Amersham, Buckinghamshire (United Kingdom)

    2015-04-01

    To assess image quality in abdominal CT at low tube voltage combined with two types of iterative reconstruction (IR) at four reduced contrast agent dose levels. Minipigs were scanned with standard 320 mg I/mL contrast concentration at 120 kVp, and with reduced formulations of 120, 170, 220 and 270 mg I/mL at 80 kVp with IR. Image quality was assessed by CT value, dose normalized contrast and signal to noise ratio (CNRD and SNRD) in the arterial and venous phases. Qualitative analysis was included by expert reading. Protocols with 170 mg I/mL or higher showed equal or superior CT values: aorta (278-468 HU versus 314 HU); portal vein (205-273 HU versus 208 HU); liver parenchyma (122-146 HU versus 115 HU). In the aorta, all 170 mg I/mL protocols or higher yielded equal or superior CNRD (15.0-28.0 versus 13.7). In liver parenchyma, all study protocols resulted in higher SNRDs. Radiation dose could be reduced from standard CTDI{sub vol} = 7.8 mGy (6.2 mSv) to 7.6 mGy (5.2 mSv) with 170 mg I/mL. Combining 80 kVp with IR allows at least a 47 % contrast agent dose reduction and 16 % radiation dose reduction for images of comparable quality. (orig.)

  13. The combination of BH3-mimetic ABT-737 with the alkylating agent temozolomide induces strong synergistic killing of melanoma cells independent of p53.

    Directory of Open Access Journals (Sweden)

    Steven N Reuland

    Full Text Available Metastatic melanoma has poor prognosis and is refractory to most conventional chemotherapies. The alkylating agent temozolomide (TMZ is commonly used in treating melanoma but has a disappointing response rate. Agents that can act cooperatively with TMZ and improve its efficacy are thus highly sought after. The BH3 mimetic ABT-737, which can induce apoptosis by targeting pro-survival Bcl-2 family members, has been found to enhance the efficacy of many conventional chemotherapeutic agents in multiple cancers. We found that combining TMZ and ABT-737 induced strong synergistic apoptosis in multiple human melanoma cell lines. When the drugs were used in combination in a mouse xenograft model, they drastically reduced tumor growth at concentrations where each individual drug had no significant effect. We found that TMZ treatment elevated p53 levels, and that the pro-apoptotic protein Noxa was elevated in TMZ/ABT-737 treated cells. Experiments with shRNA demonstrated that the synergistic effect of TMZ and ABT-737 was largely dependent on Noxa. Experiments with nutlin-3, a p53 inducer, demonstrated that p53 induction was sufficient for synergistic cell death with ABT-737 in a Noxa-dependent fashion. However, p53 was not necessary for TMZ/ABT-737 synergy as demonstrated by a p53-null line, indicating that TMZ and ABT-737 together induce Noxa in a p53-independent fashion. These results demonstrate that targeting anti-apoptotic Bcl-2 members is a promising method for treating metastatic melanoma, and that clinical trials with TMZ and Bcl-2 inhibitors are warranted.

  14. Efficacy of Lysophosphatidylcholine in Combination with Antimicrobial Agents against Acinetobacter baumannii in Experimental Murine Peritoneal Sepsis and Pneumonia Models.

    Science.gov (United States)

    Parra Millán, R; Jiménez Mejías, M E; Sánchez Encinales, V; Ayerbe Algaba, R; Gutiérrez Valencia, A; Pachón Ibáñez, M E; Díaz, C; Pérez Del Palacio, J; López Cortés, L F; Pachón, J; Smani, Y

    2016-08-01

    Immune response stimulation to prevent infection progression may be an adjuvant to antimicrobial treatment. Lysophosphatidylcholine (LPC) is an immunomodulator involved in immune cell recruitment and activation. In this study, we aimed to evaluate the efficacy of LPC in combination with colistin, tigecycline, or imipenem in experimental murine models of peritoneal sepsis and pneumonia. We used Acinetobacter baumannii strain Ab9, which is susceptible to colistin, tigecycline, and imipenem, and multidrug-resistant strain Ab186, which is susceptible to colistin and resistant to tigecycline and imipenem. Pharmacokinetic and pharmacodynamic parameters for colistin, tigecycline, and imipenem and the 100% minimal lethal dose (MLD100) were determined for both strains. The therapeutic efficacies of LPC, colistin (60 mg/kg of body weight/day), tigecycline (10 mg/kg/day), and imipenem (180 mg/kg/day), alone or in combination, were assessed against Ab9 and Ab186 at the MLD100 in murine peritoneal sepsis and pneumonia models. The levels of pro- and anti-inflammatory cytokines, i.e., tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10), were determined by enzyme-linked immunosorbent assay (ELISA) for the same experimental models after inoculating mice with the MLD of both strains. LPC in combination with colistin, tigecycline, or imipenem markedly enhanced the bacterial clearance of Ab9 and Ab186 from the spleen and lungs and reduced bacteremia and mouse mortality rates (P colistin, tigecycline, and imipenem monotherapies. Moreover, at 4 h post-bacterial infection, Ab9 induced higher TNF-α and lower IL-10 levels than those with Ab186 (4 μg/ml versus 3 μg/ml [P colistin, tigecycline, or imipenem modestly reduced the severity of infection by A. baumannii strains with different resistance phenotypes compared to LPC monotherapy in both experimental models. PMID:27161639

  15. Methods and applications of HPLC-AMS (WBio 5)

    Energy Technology Data Exchange (ETDEWEB)

    Bucholz, B A; Clifford, A J; Duecker, S R; Lin, Y; Vogel, J S

    1999-09-29

    Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a {sup 14}C-labelled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the {sup 14}C content above the control predose tissue and converting to equivalents of the parent compound. High Performance Liquid Chromatography (HPLC) is an excellent method for the chemical separation of complex mixtures whose profiles afford estimation of biochemical pathways of metabolism. Compounds elute from the HPLC systems with characteristic retention times and can be collected in fractions that can then be graphitized for AMS measurement. Unknowns are identified by coelution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the {sup 14}C signal. Thoroughly accounting for the carbon inventory in the LC solvents, ion-pairing agents, samples, and carriers adds some complexity to the analysis. In most cases the total carbon inventory is dominated by carrier. Baseline background and stability need to be carefully monitored. Limits of quantitation near 10 amol of {sup 14}C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected {sup 14}C activity <0.17 Bq (4.5 pCi) on the HPLC column.

  16. Effect of insulin-sensitizing agents in combination with ezetimibe, and valsartan in rats with non-alcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    Nimer Assy; Masha Grozovski; Ilana Bersudsky; Sergio Szvalb; Osamah Hussein

    2006-01-01

    AIM: To assess whether treatment with insulinsensitizing agents (ISAs) in combination with ezetimibe and valsartan have greater effect on hepatic fat content and lipid peroxidation compared to monotherapy in the methionine choline-deficient diet (MCDD) rat model of non-alcoholic fatty liver disease (NAFLD).METHODS: Rats (n = 6 per group) were treated with different drugs, including MCDD only, MCDD diet with either metformin (200 mg/kg), rosiglitazone (3 mg/kg),metformin plus rosiglitazone (M+R), ezetimibe (2 mg/kg), valsartan (2 mg/kg), or combination of all drugs for a total of 15 wk. Liver histology, lipids, parameters of oxidative stress and TNF-alpha were measured.RESULTS: Fatty liver (FL) rats demonstrated severe hepatic fatty infiltration (> 91% fat), with an increase in hepatic TG (+1263%, P < 0.001), hepatic cholesterol (+245%, P < 0.03), hepatic MDA levels (+225%, P <0.001), serum TNF-alpha (17.8 ± 10 vs 7.8 ± 0.0, P < 0.001), but a decrease in hepatic alpha tocopherol (-74%, P < 0.001) as compared to the control rats.Combination therapy with all drugs produced a significant decrease in liver steatosis (-54%), hepatic TG (-64%), hepatic cholesterol (-31%) and hepatic MDA (-70%), but increased hepatic alpha tocopherol (+443%)as compared to FL rats. Combination therapy with ISA alone produced a smaller decrease in liver steatosis (-32% vs -54%, P < 0.001) and in hepatic MDA levels (-55% vs -70%, P < 0.01), but a similar decrease in hepatic lipids when compared with the all drugs combination.TNF-alpha levels decreased significantly in all treatment groups except in ISA group.CONCLUSION: Combination therapies have a greater effect on liver fat content as compared to monotherapy.Rosiglitazone appears to improve hepatic steatosis to a greater extent than metformin.

  17. Low-cost fabrication of ternary CuInSe{sub 2} nanocrystals by colloidal route using a novel combination of volatile and non-volatile capping agents

    Energy Technology Data Exchange (ETDEWEB)

    Chawla, Parul; Narain Sharma, Shailesh, E-mail: shailesh@nplindia.org; Singh, Son

    2014-11-15

    Wet-route synthesis of CuInSe{sub 2} (CISe) nanocrystals has been envisaged with the utilization of the unique combination of coordinating ligand and non coordinating solvent. Our work demonstrates the formation of a single-phase, nearly stoichiometric and monodispersive, stable and well-passivated colloidal ternary CISe nanocrystals (band gap (E{sub g})∼1.16 eV) using a novel combination of ligands; viz. volatile arylamine aniline and non-volatile solvent 1-octadecene. The synthesis and growth conditions have been manoeuvred using the colligative properties of the mixture and thus higher growth temperature (∼250 °C) could be attained that promoted larger grain growth. The beneficial influence of the capping agents (aniline and 1-octadecene) on the properties of chalcopyrite nanocrystals has enabled us to pictorally model the structural, morphological and optoelectronic aspects of CISe nanoparticles. - Graphical abstract: Without resorting to any post-selenization process and using the colligative properties of the mixture comprising of volatile aniline and non-volatile 1-octadecene to manoeuvre the growth conditions to promote Ostwald ripening, a single phase, monodispersive and nearly stoichiometric ternary CISe nanocrystals are formed by wet-synthesis route. - Highlights: • Wet-route synthesis of CISe nanocrystals reported without post-selenization process. • Single-phase, stable and well-passivated colloidal ternary CISe nanocrystals formed. • Novel combination of capping agents: volatile aniline and non-volatile 1-octadecene. • Higher growth temperature attained using the colligative properties of the mixture. • Metallic salts presence explains exp. and theoretical boiling point difference.

  18. Low-cost fabrication of ternary CuInSe2 nanocrystals by colloidal route using a novel combination of volatile and non-volatile capping agents

    International Nuclear Information System (INIS)

    Wet-route synthesis of CuInSe2 (CISe) nanocrystals has been envisaged with the utilization of the unique combination of coordinating ligand and non coordinating solvent. Our work demonstrates the formation of a single-phase, nearly stoichiometric and monodispersive, stable and well-passivated colloidal ternary CISe nanocrystals (band gap (Eg)∼1.16 eV) using a novel combination of ligands; viz. volatile arylamine aniline and non-volatile solvent 1-octadecene. The synthesis and growth conditions have been manoeuvred using the colligative properties of the mixture and thus higher growth temperature (∼250 °C) could be attained that promoted larger grain growth. The beneficial influence of the capping agents (aniline and 1-octadecene) on the properties of chalcopyrite nanocrystals has enabled us to pictorally model the structural, morphological and optoelectronic aspects of CISe nanoparticles. - Graphical abstract: Without resorting to any post-selenization process and using the colligative properties of the mixture comprising of volatile aniline and non-volatile 1-octadecene to manoeuvre the growth conditions to promote Ostwald ripening, a single phase, monodispersive and nearly stoichiometric ternary CISe nanocrystals are formed by wet-synthesis route. - Highlights: • Wet-route synthesis of CISe nanocrystals reported without post-selenization process. • Single-phase, stable and well-passivated colloidal ternary CISe nanocrystals formed. • Novel combination of capping agents: volatile aniline and non-volatile 1-octadecene. • Higher growth temperature attained using the colligative properties of the mixture. • Metallic salts presence explains exp. and theoretical boiling point difference

  19. Characterization of mechanical properties of hybrid contrast agents by combining atomic force microscopy with acoustic/optic assessments.

    Science.gov (United States)

    Guo, Gepu; Tu, Juan; Guo, Xiasheng; Huang, Pintong; Wu, Junru; Zhang, Dong

    2016-02-01

    Multi-parameter fitting algorithms, which are currently used for the characterization of coated-bubbles, inevitably introduce uncertainty into the results. Therefore, a better technique that can accurately determine the microbubbles׳ mechanical properties is urgently needed. A comprehensive technology combining atomic force microscopy, optical, and acoustic measurements with simulations of coated-bubble dynamics was developed. Using this technique, the mechanical parameters (size distribution, shell thickness, elasticity, and viscosity) of hybrid (ultrasound/magnetic-resonance-imaging) contrast microbubbles and their structure-property relationship were determined. The measurements indicate that when more superparamagnetic iron oxide nanoparticles are embedded in the microbubbles׳ shells, their mean diameter and effective viscosity increase, and their elastic modulus decreases. This reduces the microbubbles׳ resonance frequency and thus enhances acoustic scattering and attenuation effects. PMID:26726783

  20. Electrochemically Pretreated Carbon Microfiber Electrodes as Sensitive HPLC-EC Detectors

    Directory of Open Access Journals (Sweden)

    Zdenka Bartosova

    2012-01-01

    Full Text Available The paper focuses on the analysis and detection of electroactive compounds using high-performance liquid chromatography (HPLC combined with electrochemical detection (EC. The fabrication and utilization of electrochemically treated carbon fiber microelectrodes (CFMs as highly sensitive amperometric detectors in HPLC are described. The applied pretreatment procedure is beneficial for analytical characteristics of the sensor as demonstrated by analysis of the model set of phenolic acids. The combination of CFM with separation power of HPLC technique allows for improved detection limits due to unique electrochemical properties of carbon fibers. The CFM proved to be a promising tool for amperometric detection in liquid chromatography.

  1. Electrochemically Pretreated Carbon Microfiber Electrodes as Sensitive HPLC-EC Detectors

    Science.gov (United States)

    Bartosova, Zdenka; Riman, Daniel; Jakubec, Petr; Halouzka, Vladimir; Hrbac, Jan; Jirovsky, David

    2012-01-01

    The paper focuses on the analysis and detection of electroactive compounds using high-performance liquid chromatography (HPLC) combined with electrochemical detection (EC). The fabrication and utilization of electrochemically treated carbon fiber microelectrodes (CFMs) as highly sensitive amperometric detectors in HPLC are described. The applied pretreatment procedure is beneficial for analytical characteristics of the sensor as demonstrated by analysis of the model set of phenolic acids. The combination of CFM with separation power of HPLC technique allows for improved detection limits due to unique electrochemical properties of carbon fibers. The CFM proved to be a promising tool for amperometric detection in liquid chromatography. PMID:22654586

  2. [Determination of amanitatoxins by HPLC].

    Science.gov (United States)

    Nishizawa, Chiemi; Yamaura, Yoshio

    2003-10-01

    High-performance liquid chromatographic (HPLC) assay has been developed for the simultaneous determination of alpha-amanitin, beta-amanitin and phalloidin in serum. Three toxins were extracted by reflux in a water bath at 80 degrees C for one hour and purified by Sep-Pak Plus tC18 cartridges. The HPLC assay was performed under gradient conditions using Develosil RP AQUEOUS column. The moble phase consisted with a mixture of acetonitorile containing 0.01 M ammonium acetate(pH 5.0). The column effluence was monitored at 295 nm, 302 nm and 230 nm for 35 min. Detection limit of three toxins in serum were 0.2 microgram/ml respectively. High recovery yields in the range of 81.5-88.1% for toxins were obtained by using this method. PMID:14740566

  3. Combined effects of radiation and other agents on the stomach cancer incidence among Mayak Atomic Plant workers

    International Nuclear Information System (INIS)

    The gravity of a problem of the combined action of radiation and other factors again was confirmed sessions UNSCEAR in May, 1998. It especially is important at study of cancer diseases in connection with the polyetiology and multistage of them development. The estimation of radiation, medico-biological factors and condition of life in occurrence of a stomach cancer among Mayak personnel was specified by case-cohort research. For a quota 503 men (157 cases of a stomach cancer, 346 men of the healthy personnel) attributive risk of the radiation factors was 8.8%, medico-biological - 57,2% (from them by greatest was influence chronic gastritis with secreting insufficiency - 35.4%), tobacco consumption - 31,6%. At an estimation of risk of a stomach cancer depending on external γ-irradiation best fitting was received at use of square-law model. The excess relative risk was 0,27 Gr-2 (F=44,5; P=0,007). For 239Pu incorporation was not revealed of distinct connection with stomach cancer incidences. Interaction of the radiation and non-radiation factors also was appreciated. The interaction of gastritis with external γ-irradiation or 239Pu was multiplicate. The interaction of smoking with γ-irradiation or 239Pu incorporation was multiplicate also. The distribution histological types of a stomach cancer among the workers of Mayak plant differed in comparison with not working. Among the workers the increase poorly differentiated adenocarcinoma was observed. (author)

  4. Safety of an oral anticancer agent (trifluridine/tipiracil combination tablet) in patients with advanced and recurrent colorectal cancer.

    Science.gov (United States)

    Kimura, M; Go, M; Iwai, M; Ito, D; Asano, H; Usami, E; Teramachi, H; Yoshimura, T

    2016-04-01

    We retrospectively studied the safety of trifluridine/tipiracil combination tablet (TAS-102) monotherapy in patients with advanced and recurrent colorectal cancer. Adverse events to TAS-102 monotherapy were observed in 22 out of 23 cases (95.7%). The most frequent adverse events were neutropenia (69.6%), nausea (53.2%), and malaise (30.4%). Treatment was postponed in 54 (59.3%) out of 91 courses, and in 34 (66.7%) of these 54 courses, the delay in treatment was due to bone marrow suppression. Seven patients with peritoneal metastases suffered from nausea, whilst none of the patients without peritoneal metastases had nausea (p = 0.0139). Nausea and vomiting during a previous chemotherapy cycle was significantly associated with nausea after TAS-102 treatment (p = 0.0007), and the treatment cycles were significantly longer in patients with grade 3 or 4 neutropenia (p = 0.0061). Our results suggest that the incidence of nausea was higher in patients treated with TAS-102. Therefore, it is important to inform patients of the risk of these toxicities and to provide enhanced supportive care. Moreover, we recommend that, for patients with repeated treatment postponement due to neutropenia, the dosage should be fixed based on therapeutic efficacy and prognosis. PMID:27209703

  5. Combined effects of radiation and other agents on the stomach cancer incidence among Mayak Atomic Plant workers

    Energy Technology Data Exchange (ETDEWEB)

    Zhuntova, G.V.; Tokarskaya, Z.B.; Belyaeva, Z.D. [Branch No 1 of State Research Center of Public Health Ministry of the Russian Federation, Ozyorsk (Russian Federation). Biophysics Inst.; Rovny, S.I.; Sirchikov, V.A.

    2000-05-01

    The gravity of a problem of the combined action of radiation and other factors again was confirmed sessions UNSCEAR in May, 1998. It especially is important at study of cancer diseases in connection with the polyetiology and multistage of them development. The estimation of radiation, medico-biological factors and condition of life in occurrence of a stomach cancer among Mayak personnel was specified by case-cohort research. For a quota 503 men (157 cases of a stomach cancer, 346 men of the healthy personnel) attributive risk of the radiation factors was 8.8%, medico-biological - 57,2% (from them by greatest was influence chronic gastritis with secreting insufficiency - 35.4%), tobacco consumption - 31,6%. At an estimation of risk of a stomach cancer depending on external {gamma}-irradiation best fitting was received at use of square-law model. The excess relative risk was 0,27 Gr{sup -2} (F=44,5; P=0,007). For {sup 239}Pu incorporation was not revealed of distinct connection with stomach cancer incidences. Interaction of the radiation and non-radiation factors also was appreciated. The interaction of gastritis with external {gamma}-irradiation or {sup 239}Pu was multiplicate. The interaction of smoking with {gamma}-irradiation or {sup 239}Pu incorporation was multiplicate also. The distribution histological types of a stomach cancer among the workers of Mayak plant differed in comparison with not working. Among the workers the increase poorly differentiated adenocarcinoma was observed. (author)

  6. 葡聚糖凝胶微柱-HPLC测定氯雷他定二元醇质体包封率%Determination of Entrapment Efficiency of Loratadine Binary Ethosomes by Sephadex Microcolumn Com-bined with HPLC

    Institute of Scientific and Technical Information of China (English)

    柴俊; 陈鹰; 李凯

    2015-01-01

    Objective:To establish a method to determine the entrapment efficiency of loratadine binary ethosomes. Methods:The gel microcolumn centrifugation method was employed to separate the free drug from loratadine binary ethosomes. The content of lorata-dine was determined by HPLC to calculate the entrapment efficiency. Results: A calibration linear curve of loratadine concentration was within the range of 10. 2-102. 0 μg·ml-1(r=0. 999 5). The average entrapment efficiencies of three batches of loratadine binary ethosomes were 86. 75%, 87. 26% and 86. 00%, respectively. Conclusion:The method is simple and rapid, and can be used to de-termine the entrapment efficiency of loratadine binary ethosomes accurately.%目的::建立氯雷他定二元醇质体包封率的测定方法。方法:采用凝胶微柱离心法分离游离药物与二元醇质体,以HPLC测定氯雷他定的药物含量,计算二元醇质体的包封率。结果:氯雷他定浓度在10.2~102.0μg·ml-1内线性关系良好(r=0.9995)。3批次氯雷他定二元醇质体的包封率分别为86.75%,87.26%,86.00%。结论:该方法简便、迅速,可准确测定氯雷他定二元醇质体的包封率。

  7. The dataset from administration of single or combined immunomodulation agents to modulate anti-FVIII antibody responses in FVIII plasmid or protein primed hemophilia A mice.

    Science.gov (United States)

    Liu, Chao Lien; Lyle, Meghan J; Shin, Simon C; Miao, Carol H

    2016-06-01

    Hemophilia A mice with pre-existing inhibitory antibodies against factor VIII (FVIII) were treated with single agents, AMD3100 and GCS-F, respectively. Inhibitor titers in treated mice and control HemA inhibitors mice were followed over time. Total B cells and plasma cells (PCs) were characterized by flow cytometry. HemA inhibitor mice were then treated with a combination regimen of IL-2/IL-2mAb complexes plus rapamycin and AMD3100. Finally, HemA inhibitor mice were treated with a new combination therapy using include IL-2/IL-2mAb complexes + Anti-CD20+AMD3100+G-CSF. The timeline of combination therapy was illustrated. Inhibitor titers following treatment in FVIII plasmid or protein induced inhibitor mice were evaluated overtime. A representative figure and gating strategies to characterize the subsets of Treg cells and B cells are presented. Please see http://dx.doi.org/10.1016/j.cellimm.2016.01.005 [1] for interpretation and discussion of these data and results. PMID:27081675

  8. Prevention of enzymatic browning of yacon flour by the combined use of anti-browning agents and the study of its chemical composition

    Directory of Open Access Journals (Sweden)

    Oscar Romero Lopes Rodrigues

    2014-06-01

    Full Text Available Yacon roots present functional properties because of the high levels of fructooligosaccharides (FOS, which are considered as prebiotic fibers. In addition, yacon roots are rich in phenolic compounds. During the processing of yacon, the freshly cut surface undergoes rapid enzymatic browning. Control of enzymatic browning during processing is very important to preserve the appearance of yacon flour. In this study, it was evaluated the combined effect of anti-browning agents (ascorbic acid, citric acid and L-cysteine on the inhibition of enzymatic browning of yacon, using Response Surface Methodology. The yacon pre-treated with anti-browning agents in concentrations of 15.0 mM for ascorbic acid, 7.5 mM for citric acid and 10.0 mM for L-cysteine was used for the processing of flour. Yacon flour presented an attractive color and good sensory properties, without residual aroma. The contents of FOS and phenolic compounds obtained in yacon flour were 28.60 g.100 g- 1 and 1.35 g.100 g- 1. Yacon flour can be considered as a potential functional food, especially due to high levels of FOS, which allows for its use in formulation of various foods.

  9. Chromatographic separation of simulants of nerve and blister agents by combining one- and two-channel columns with different stationary phases.

    Science.gov (United States)

    Yuan, Huan; Du, Xiaosong; Li, Yi; Zhao, Xulan; Xu, Ming

    2016-04-01

    A two-channel gas chromatography column and a single-channel column were made by deep reactive-ion etching technology. The two short columns were coated with different stationary phases, and then linked without a modulator. This is to aim at increasing the sample capacity and achieving a higher separation efficiency in complex environments. The results show that the capacity of the connected column is approximately 4 and 1.5 times larger than that of the single- and two-channel columns, respectively. The linked column was utilized to separate a six-component mixture, composed of three simulants of nerve and blister agents and three interfering vapors. The results demonstrate that the combined column has a remarkably higher separation efficiency than the individual columns, and an acceptable resolution is achieved although the total length of the linked column is only 1.5 m. PMID:26843525

  10. A fully automated and fast method using direct sample injection combined with fused-core column on-line SPE-HPLC for determination of ochratoxin A and citrinin in lager beers.

    Science.gov (United States)

    Lhotská, Ivona; Šatínský, Dalibor; Havlíková, Lucie; Solich, Petr

    2016-05-01

    A new fast and sensitive method based on on-line solid-phase extraction on a fused-core precolumn coupled to liquid chromatography with fluorescence detection has been developed for ochratoxin A (OTA) and citrinin (CIT) determination in lager beer samples. Direct injection of 100 μL filtered beer samples into an on-line SPE-HPLC system enabled fast and effective sample extraction including separation in less than 6 min. Preconcentration of OTA and CIT from beer samples was performed on an Ascentis Express RP C18 guard column (5 × 4.6 mm), particle size 2.7 μm, with a mobile phase of methanol/0.5 % aqueous acetic acid pH 2.8 (30:70, v/v) at a flow rate of 2.0 mL min(-1). The flow switch from extraction column to analytical column in back-flush mode was set at 2.0 min and the separation was performed on the fused-core column Ascentis Express Phenyl-Hexyl (100 × 4.6 mm), particle size 2.7 μm, with a mobile phase acetonitrile/0.5 % aqueous acetic acid pH 2.8 in a gradient elution at a flow rate of 1.0 mL min(-1) and temperature of 50 °C. Fluorescence excitation/emission detection wavelengths were set at 335/497 nm. The accuracy of the method, defined as the mean recoveries of OTA and CIT from light and dark beer samples, was in the range 98.3-102.1 %. The method showed high sensitivity owing to on-line preconcentration; LOQ values were found to be 10 and 20 ng L(-1) for OTA and CIT, respectively. The found values of OTA and CIT in all tested light, dark and wheat beer samples were significantly below the maximum tolerable limits (3.0 μg kg(-1) for OTA and 2000 μg kg(-1) for CIT) set by the European Union. Graphical Abstract The beer contamination - potential sources of mycotoxins. PMID:26993307

  11. Management of symptomatic erosive-ulcerative lesions of oral lichen planus in an adult Egyptian population using Selenium - ACE combined with topical corticosteroids plus antifungal agent

    Directory of Open Access Journals (Sweden)

    Mahmoud Helmy Belal

    2015-01-01

    Full Text Available Aim: Oral lichen planus (OLP is a chronic mucocutaneous disease with an immunological etiology. This study was conducted to evaluate the effect of selenium combined with Vitamins A, C & E (Selenium-ACE in the treatment of erosive-ulcerative OLP as an adjunctive to topical corticosteroids plus antifungal agent. Subjects and Methods: Thirty patients with a confirmed clinical and histopathologic diagnosis of OLP participated in this clinical trial. Patients were randomly allocated into one of three groups and treated as follows: (I Topical corticosteroids, (II topical corticosteroids plus antifungal, and (III SE-ACE combined with topical corticosteroids plus antifungal. The patients were followed for 6 weeks. The pain and severity of the lesions were recorded at the initial and follow-up visits. All recorded data were analyzed using paired t-test and ANOVA test. A P ≤ 0.05 was considered significant. Results: The experimental groups showed a marked reduction in pain sensation and size of lesions, particularly in the final follow-up period, but there was no significant difference between the first two Groups I and II. However, healing of lesions and improvement of pain sensation was effective in Group III since a significant difference was found favoring Group III over both Groups I and II. Conclusion: No significant difference was found in treating erosive-ulcerative lesions of OLP by topical corticosteroids alone or combined with antifungal. However, when using SE-ACE in combination with topical corticosteroids plus antifungal, this approach may be effective in managing ulcerative lesions of OLP; but more research with a larger sample size and a longer evaluation period may be recommended.

  12. Serotonin neurotoxicity in rats after combined treatment with a dopaminergic agent followed by a nonneurotoxic 3,4-methylenedioxymethamphetamine (MDMA) analogue.

    Science.gov (United States)

    Johnson, M P; Huang, X M; Nichols, D E

    1991-12-01

    There is increasing evidence linking dopamine (DA) to the long-term serotonergic (5-HT) neurotoxic effects of certain substituted amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA). The present study was undertaken to examine the importance of DA metabolism, uptake inhibition and release in the long-term effects of these drugs by combining various dopaminergic agents with an analogue of MDMA that had low neurotoxic liability, namely 5,6-methylenedioxy-2-aminoindan (MDAI). Monoamine and metabolite levels and the number of 5-HT uptake sites (using [3H]paroxetine binding) were determined 3 hours or 1 week after treatments. Combining the monoamine oxidase inhibitors, clorgyline (MAOA selective) or deprenyl (MAOB selective) with MDAI did not result in any long-term reductions of serotonergic markers. Similarly, combining the DA uptake inhibitor GBR-12909 with MDAI did not result in any long-term changes in monoamine levels at 1 week. In contrast, a single pretreatment of posttreatment with the nonvesicular DA releaser S-amphetamine and MDAI resulted in small but significant long-term changes in monoamine levels. More importantly, if a subacute dosing regimen (every 12 hours for 4 days) was utilized, the combination of S-amphetamine with MDAI resulted in a marked long-term decrease in the levels of cortical, hippocampal and striatal 5-HT, 5-HIAA and the number of 5-HT uptake sites. The results are discussed in terms of the significance of DA and especially nonvesicular DA release in the long-term effects of MDMA-like drugs. PMID:1726189

  13. Phase IB study of doxorubicin in combination with the multidrug resistance reversing agent S9788 in advanced colorectal and renal cell cancer.

    Science.gov (United States)

    Punt, C J; Voest, E E; Tueni, E; Van Oosterom, A T; Backx, A; De Mulder, P H; Hecquet, B; Lucas, C; Gerard, B; Bleiberg, H

    1997-01-01

    S9788 is a new triazineaminopiperidine derivate capable of reversing multidrug resistance (MDR) in cells resistant to chemotherapeutic agents such as doxorubicin. It does not belong to a known class of MDR revertants, but its action involves the binding of P-glycoprotein. Thirty-eight evaluable patients with advanced colorectal or renal cell cancer were treated with doxorubicin alone (16 patients) followed after disease progression with combination treatment of doxorubicin plus S9788 (12 patients) or upfront with the combination of doxorubicin plus S9788 (22 patients). S9788 was given i.v. as a loading dose of 56 mg m-2 over 30 min followed by doxorubicin given at 50 mg m-2 as a bolus infusion. Thereafter, a 2-h infusion of S9788 was administered at escalating doses ranging from 24 to 120 mg m-2 in subsequent cohorts of 4-10 patients. Pharmacokinetic analysis demonstrated that concentrations of S9788 that are known to reverse MDR in vitro were achieved in patients at non-toxic doses. Compared with treatment with doxorubicin alone, treatment with the combination of doxorubicin and S9788 produced a significant increase in the occurrence of WHO grade 3-4 granulocytopenia. Treatment with S9788 was cardiotoxic as it caused a dose-dependent and reversible increase in corrected QT intervals as well as clinically non-significant arrhythmias on 24- or 48-h Holter recordings. Although clinically relevant cardiac toxicities did not occur, the study was terminated as higher doses of S9788 may increase the risk of severe cardiac arrhythmias. Twenty-nine patients treated with S9788 plus doxorubicin were evaluable for response, and one patient, who progressed after treatment with doxorubicin alone, achieved a partial response. We conclude that S9788 administered at the doses and schedule used in this study results in relevant plasma concentrations in humans and can safely be administered in combination with doxorubicin. PMID:9374386

  14. Clinical outcomes of tigecycline alone or in combination with other antimicrobial agents for the treatment of patients with healthcare-associated multidrug-resistant Acinetobacter baumannii infections.

    Science.gov (United States)

    Lee, Y-T; Tsao, S-M; Hsueh, P-R

    2013-09-01

    Tigecycline (TG) has been shown to be active in vitro against Acinetobacter baumannii, although data on the clinical efficacy of TG alone or in combination for the treatment of infections due to multidrug-resistant A. baumannii (MDRAB) remain limited. The purpose of this study was to investigate the clinical outcomes of patients with healthcare-associated infections (HAIs) caused by MDRAB who were treated with imipenem/cilastatin and sulbactam, and TG alone or in combination with other antibiotics. A total of 386 patients with HAIs caused by MDRAB were retrospectively analyzed and grouped into TG and non-TG groups, depending on whether they received TG treatment. Of the 266 patients in the TG group, 108 were treated with TG alone and 158 were treated with TG in combination with ceftazidime, ceftriaxone, piperacillin/tazobactam, or a carbapenem. All 120 patients in the non-TG group were treated with imipenem/cilastatin and sulbactam. The primary outcome measure was 30-day mortality after TG treatment and the secondary outcome was clinical outcome. There were no significant differences in survival rates between the two groups. However, the rate of unfavorable outcome was significantly lower (p < 0.05) among patients in the TG group than among patients in the non-TG group. The most significant predictor of unfavorable outcome was sepsis, whereas TG treatment and microbial eradication were the most significant predictors of favorable outcomes. Our study represents the largest study of patients with MDRAB infection treated with TG and expands our understanding of the role of TG therapy alone or in combination with other agents for the treatment of HAI caused by MDRAB. PMID:23553594

  15. The use of injectable alphaxalone as a single agent and in combination with ketamine, xylazine, and morphine in the Chilean rose tarantula, Grammostola rosea.

    Science.gov (United States)

    Gjeltema, Jenessa; Posner, Lysa P; Stoskopf, Michael

    2014-12-01

    This study evaluated the use of the injectable anesthetic, alphaxalone, as a single agent and in combination with ketamine, xylazine, and morphine in the Chilean rose tarantula, Grammostola rosea. Between two and four animals were evaluated for each anesthetic protocol, and two unanesthetized animals were evaluated for comparative purposes. Anesthetic duration, depth, and quality were assessed by scoring responses to tactile and trichobothria stimulation, muscle tone, purposeful movement, righting response, and heart rate throughout each anesthetic event. Alphaxalone administered into the dorsal opisthosoma in the location of the heart at 200 mg/kg produced moderate anesthetic effect with a median duration of 28 min (n = 3; range 25-50). A combination of 200 mg/kg of alphaxalone and 20 mg/kg of ketamine induced a deep anesthetic state with a median anesthetic duration of 27 min (n = 4; range 16-42). The combination of 200 mg/kg of alphaxalone and 20 mg/kg of xylazine produced deep anesthesia with a median duration of 70 min (n = 4; range 37-207). Morphine administered at 5 mg/kg 30 min prior to injection with 200 mg/kg alphaxalone had anesthetic durations of 9 and 30 min (n = 2). Heartbeats could not be detected for periods of 7-27 min following anesthetic induction for the majority of animals receiving the alphaxalone/ketamine and alphaxalone/xylazine anesthetic combinations. No mortality was associated with any of the anesthetic protocols used; however, ambient temperature and ecdysis were identified as important factors that may alter response to anesthetics in these animals. PMID:25632665

  16. Rare earth element determination by HPLC method with postcolumn derivatization

    International Nuclear Information System (INIS)

    Standard rare earth element solutions were prepared from the oxides of the elements. HPLC was used for the element separation and determination. Three complex-forming agents were used for derivation. The best results were achieved when arsenazo III was used. With Chromazurol S at pH = 9.5, the results were significantly dependent on the agent age while chlorophosphonazo III showed significantly lower sensitivity. The optimum values were determined of pH, agent concentration, capillary length and flow rate. The suitability of the method developed was tested on standard materials. Accuracy of determination for the individual elements ranged within 1.6% (Nd) and 7.4% (Eu). The duration of analysis was 25 minutes for a sample containing all lanthanoids. (M.D.). 1 fig., 1 tab., 28 refs

  17. The efficacy and tolerability of the slow-acting combined agent glucosamine and chondroitin sulfate in gonarthrosis patients tacking no nonsteroidal anti-inflammatory drugs

    Directory of Open Access Journals (Sweden)

    A. P. Rebrov

    2015-01-01

    Full Text Available Objective: to evaluate the efficacy and tolerability of the combined symptomatic slow-acting combined agent Theraflex in gonarthrosis patients untreated with nonsteroidal antiinflammatory drugs (NSAIDs.Patients and methods. The investigation enrolled 84 patients (78 women and 6 men aged 55.23±7.36 years with knee arthritis lasting 6.2±0.98 years who were blindly randomized into 2 groups. A study group took Theraflex (chondroitin sulfate 400 mg and glucosamine sulfate 500 mg with or without acetaminophen. A comparison group received acetaminophen only. At baseline and 3 and 6 months after treatment, the investigators assessed changes in the magnitude of osteoarthritis (OA using WOMAC and Lequen's indices, evaluated the therapeutic efficiency rated by a patient and a physician according to the visual analogue scale, and took into account adverse reactions (AR.Results. All the patients taking Theraflex for 6 months showed a positive effect in substantially lowering WOMAC and Lequen's indices and reducing pain and needs for analgesics as compared to both the values at baseline and those obtained in the patients receiving acetaminophen only.Conclusion. In osteoarthritis patients untreated with NSAIDs, Theraflex treatment was associated with a reduction in pain syndrome and stiffness and with better function and lower needs for analgesics. Six-month Theraflex therapy did not cause serious ARs, as well as in patients having controlled gastrointestinal and renal diseases and hypertension

  18. A new method of inhibiting pollutant release from source water reservoir sediment by adding chemical stabilization agents combined with water-lifting aerator

    Institute of Scientific and Technical Information of China (English)

    Beibei Chai; Tinglin Huang; Weihuang Zhu; Fengying Yang

    2011-01-01

    Source water reservoirs easily become thermally and dynamically stratified.Internal pollution released from reservoir sediments is the main cause of water quality problems.To mitigate the internal pollution more effectively,a new method,which combined chemical stabilization with water lifting aerator (WLA) technology,was proposed and its efficiency in inhibiting pollutant release was studied by controlled sediment-water interface experiments.The results showed that this new method can inhibit pollutant release from sediment effectively.The values of mean efficiency (E) in different reactors 2#-5# (1# with no agent,2# 10 mg/L polymeric aluminum chloride (PAC) was added,3# 20 mg/L PAC was added,4# 30 mg/L PAC was added,5# 20 mg/L PAC and 0.2 mg/L palyacrylamide (PAM)were added) for PO43- were 35.0%,43.9%,50.4% and 63.6%,respectively.This showed that the higher the PAC concentration was,the better the inhibiting efficiency was,and PAM addition strengthened the inhibiting efficiency significantly.For Fe2+,the corresponding values of E for the reactors 2#-5# were 22.9%,47.2%,34.3% and 46.2%,respectively.The inhibiting effect of PAC and PAM on Mn release remained positive for a relatively short time,about 10 days,and was not so effective as for PO43- and Fe2+.The average efliciencies in inhibiting the release of UV254 were 35.3%,25.9%,35.5%,38.9% and 39.5% for reactors 2#-5#,respectively.The inhibiting mechanisms of the agents for different pollutants varied among the conditions and should be studied further.

  19. The effect of the combination of two biological control agents, Mirabilis jalapa and Bacillus thuringiensis, to Spodoptera litura's immune response and their mortality

    Science.gov (United States)

    Maulina, Dina; Anggraeni, Tjandra

    2014-03-01

    Biological control provides a safer alternative to reduce the population of agricultural pest. Mirabilis jalapa is one of many promising biopesticides which contains chemical substances that have a feeding deterrent property against insects. This biopesticide may not kill insect directly but will weaken their overall physiological condition. In this study, we investigated the immune response of common pestSpodoptera litura after exposure of M. jalapa extract. We also used Bacillus thuringiensis (Bt) delta endotoxin (LC50) on 3 hours after exposure of M. jalapa extract to see the synergism properties of both biopesticide agents. Microscopic observation revealed that at least 5 types of haemocyte were found in S. litura. In control group, plasmatocyte were found at 59.98%, prohaemocyte 20.73%, granullar cell 12.74%, oenocytoid 3.33% and spherule cell 3.20%. These proportion was differ significantly in the treatment group. Exposure to 0.1% and 0.2%(w/v) of M. jalapa extract increased the total number of haemocytes as much as 38.08% and 64.15% respectively. In contrast, exposure to 0.4% and 0.8%(w/v) reduced the number of haemocytes to 37.02% and 51.04% respectively. In term of phagocytic activity, the proportion of phagocytosing cells were 47.62% in control group, and in 0.1% and 0.2% (w/v) M. jalapa treatment group the proportion decreased to 28% and 26.88% respectively. In the concentration of 0.4% and 0.8%, phagocytic activity did not occur. Addition of biological agents Bt (LC50 concentration) to see mortality 3 hours after M. jalapa application did not show significant differences. S. litura mortality rate were found only 50%; this suggests that the combination of M. jalapa and Bt biopesticides in 3-hour intervals within 24 hours showed no increase in mortality.

  20. Normal tissue toxicity of upper hemibody irradiation (UHBI) when used as a non-cross resistant agent in combination with chemotherapy in the treatment of small cell lung cancer (SCLC)

    International Nuclear Information System (INIS)

    Previous studies at this Institute have investigated the use of HBI as a consolidation agent in the treatment of SCLC. The present Phase I-II study investigates the toxicity and efficacy of UHBI used as a non-cross resistant alternating agent with chemotherapy early in the induction phase of treatment of all stages of SCLC. Toxicity due to the combined effects of chemotherapy plus UHBI is reported as well as effects on bone marrow, lungs and GI tract. The increased incidence of pneumonitis observed in the present study points to a possible interaction of these modalities when HBI is being used as an alternating agent with Cisplatin and Adriamycin

  1. Development Trend of Green and Eco-friendly Biomass Leather Tanning Agent and its Combination Tanning%生物质皮革鞣剂及其结合鞣应用的发展趋势

    Institute of Scientific and Technical Information of China (English)

    杨文强; 贺亚亚; 邓丽娟

    2015-01-01

    In this paper, the research progress of biomass tanning agents such as amino acids tanning a-gents and plant biomass green tanning agent was reviewed. And their utilization in combination tanning process was also introduced briefly.%综述了氨基酸类鞣剂和植物类鞣剂等生物质类皮革鞣剂的研究进展,简述了生物质鞣剂在结合鞣中的应用。

  2. Comparison of the protective effects of various antiulcer agents alone or in combination on indomethacin-induced gastric ulcers in rats.

    Science.gov (United States)

    Izzettin, Fikret Vehbi; Sancar, Mesut; Okuyan, Betul; Apikoglu-Rabus, Sule; Cevikbas, Ugur

    2012-05-01

    The aim of this study which was structured with the objective of determination of the optimum protective therapy against the long term NSAID therapy-induced ulcers was to compare the gastro-protective effects of various antiulcer drugs (ranitidine, omeprazole, bismuth and misoprostol) alone or in combination with each other in different doses on indomethacin-induced gastric ulcers in rats. In this experimental study the protective effect of misoprostol (100 μg/kg/day and 10 μg/kg/day i.g.), omeprazole (5 mg/kg/day and 1.5 mg/kg/day i.p.), ranitidine (40 mg/kg/day and 10 mg/kg/day i.p.), bismuth (70 mg/kg/day and 15 mg/kg/day i.g.), combinations of misoprostol (10 μg/kg/day i.g.) plus omeprazole (1.5mg/kg/day i.p.) and misoprostol (10 μg/kg/day i.g.) plus ranitidine (10 mg/kg/day i.p.) are investigated on indomethacin (50 mg/kg/day s.c.) induced gastric ulcers. Half an hour before indomethacin administration, each group received the above treatment regimens for 5 days. After 5-day treatment, the rats were sacrificed and histopathological and hematological examinations were performed. The following regimens were found to be effective in the prevention of indomethacin-induced gastric lesions: 100 μg/kg misoprostol, 10 μg/kg misoprostol, 5mg/kg omeprazole, combination of 10 μg/kg misoprostol plus 1.5 mg/kg omeprazole and 10 μg/kg misoprostol plus 10 mg/kg ranitidine. The prevention rates achieved by these treatments were 71.4%, 50%, 47.6%, 52.4% and 50%, respectively. As a result of this study, misoprostol and omeprazol were found to be effective in protection against NSAID-induced gastric problems; while, ranitidine and bismuth were not. Also, the combinations of these agents were not found to have additive or synergistic effects. PMID:21030227

  3. Polyphenolic profile characterization of Agrimonia eupatoria L. by HPLC with different detection devices

    OpenAIRE

    Correia, Helena; González-Paramás, Ana; Amaral, Maria Teresa; Santos-Buelga, Celestino; Batista, Maria Teresa

    2006-01-01

    Liquid chromatography coupled to diode array and electrospray ionization mass spectrometry detection was used to establish the polyphenolic profile of an ethyl acetate fraction from Agrimonia eupatoria L. aqueous-alcoholic extract. Additionally, an HPLC technique with post-column derivatization by p-dimethylaminocinnamaldehyde was employed for the selective detection and quantification of flavan-3-ols. Important information was obtained by combining the data of these two HPLC techniques. Flav...

  4. In vitro and in vivo efficacy of afatinib as a single agent or in combination with gemcitabine for the treatment of nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Xue C

    2016-03-01

    Full Text Available Cong Xue,1 Ying Tian,2 Jing Zhang,3 Yuanyuan Zhao,1 Jianhua Zhan,2 Wenfeng Fang,1 Li Zhang1 1Department of Medical Oncology, 2Department of Research, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, 3Department of Medical Oncology, The First Affiliated Hospital of Guangzhou Traditional Chinese Medicine University, Guangzhou, Guangdong, People’s Republic of China Purpose: Epidermal growth factor receptor (EGFR is usually overexpressed in nasopharyngeal carcinoma (NPC. We tested the antitumor effects of irreversible ErbB family inhibitor afatinib on human NPC using in vitro and in vivo models.Materials and methods: The effect of afatinib on NPC cells was evaluated using the Cell Counting Kit 8 (CCK8 assay, flow cytometry, and Western blot analyses. The effect of afatinib, as either a single agent or in combination with gemcitabine (GEM, on tumor growth was determined using NPC tumor xenografts in mice.Results: Afatinib inhibited cell growth in all three NPC cell lines tested in a dose-dependent manner. Afatinib promoted cell cycle arrest at the S and G2/M phases, and it significantly inhibited epidermal growth factor (EGF-induced activation of EGFR and its downstream signaling factors. Co-treatment with afatinib and GEM more effectively inhibited tumor growth than either drug alone but was associated with increased toxicity.Conclusion: Afatinib induced cell cycle arrest and inhibited the proliferation of NPC cell lines. Afatinib in combination with GEM demonstrated significant antitumor effect in an NPC xenograft model. The administration of afatinib with GEM in NPC needs to be modified in order to be effective and tolerable. Keywords: nasopharyngeal carcinoma, EGFR, afatinib, gemcitabine, preclinical

  5. The treatment of advanced stage favorable histology non-Hodgkin's lymphoma: a preliminary report of a randomized trial comparing single agent chemotherapy, combination chemotherapy, and whole body irradiation

    International Nuclear Information System (INIS)

    Between 1975 and 1978, 51 patients with favorable histology non-Hodgkin's lymphomas, pathologic stage III-IV, were treated prospectively on a randomized treatment protocol. Treatment options were single alkylating agent chemotherapy, combination chemotherapy with cyclophosphamide, vincristine, and prednisone (CVP), or fractionated whole body irradiation followed by low dose involved field irradiation. The median follow-up interval in this group of patients is not 41 mo. Actuarial survival is excellent, 84% at 4 yr for the entire group, with similar survival observed for each of the three treatment options. Initial complete remission rates (64%, 88%, and 71%) were not significantly different in the three treatment arms. Frequent relapse after initial remission induction was noted, however, with a freedom from relapse at 4 yr of only 25%. The toxicities of the three therapies were acceptable. Acute complications of therapy were most numerous in the group of patients treated with CVP; however, long-term hematologic depression was most commonly observed in patients treated with whole body irradiation. In general, hematologic complications were more frequent among patients who had marrow involvement and intact spleens at the time of initial therapy. The relationship of this study to other clinical trials in the management of patients with advanced stage favorable histology lymphomas and its implications for future clinical trials are discussed

  6. Combined magnetic resonance imaging of deep venous thrombosis and pulmonary arteries after a single injection of a blood pool contrast agent

    Energy Technology Data Exchange (ETDEWEB)

    Hansch, Andreas; Neumann, Steffi; Baltzer, Pascal; Waginger, Matthias; Kaiser, Werner A.; Mentzel, Hans-Joachim [Friedrich-Schiller-University Jena, Institute of Diagnostic and Interventional Radiology, Jena (Germany); Betge, Stefan; Poehlmann, Gunther [Friedrich-Schiller-University Jena, Department of Internal Medicine I, Jena (Germany); Pfeil, Alexander; Wolf, Gunter [Friedrich-Schiller-University Jena, Department of Internal Medicine III, Jena (Germany); Boettcher, Joachim [SRH Klinikum Gera, Institute of Diagnostic and Interventional Radiology, Gera (Germany)

    2011-02-15

    Agreement rate between magnetic resonance imaging (MRI) and Doppler ultrasound (DUS) for the detection of deep vein thrombosis (DVT) in the lower extremities was attempted by using the intravascular MRI contrast agent gadofosveset trisodium. The potential of this method to detect pulmonary embolism (PE) was also evaluated. Forty-three consecutive inpatients with ultrasound-confirmed DVT but no clinical signs of PE were prospectively enrolled in this feasibility study. MRI was performed after a single injection of gadofosveset trisodium. The pulmonary arteries were imaged using a 3D Fast Low Angle Shot (FLASH) gradient recalled echo sequence. Additionally, pulmonary arteries, abdominal veins, pelvic and leg veins were imaged using a fat-suppressed 3D gradient echo Volume Interpolated Breath-hold Examination (VIBE FS). Gadofosveset trisodium-enhanced MRI detected more thrombi in the pelvic region, upper leg and lower leg than the initial DUS. In addition, PE was detected in 16 of the 43 DVT patients (37%). This study shows the feasibility of a combined protocol for the MRI diagnosis of DVT and PE using gadofosveset trisodium. This procedure is not only more sensitive in detecting DVT compared to standard DUS, but is also able to detect PE in asymptomatic patients. (orig.)

  7. Non-surgical treatment of deep wounds triggered by harmful physical and chemical agents: a successful combined use of collagenase and hyaluronic acid.

    Science.gov (United States)

    Onesti, Maria G; Fino, Pasquale; Ponzo, Ida; Ruggieri, Martina; Scuderi, Nicolò

    2016-02-01

    Some chronic ulcers often occur with slough, not progressing through the normal stages of wound healing. Treatment is long and other therapies need to be performed in addition to surgery. Patients not eligible for surgery because of ASA class (American Society of Anesthesiologists class) appear to benefit from chemical therapy with collagenase or hydrocolloids in order to prepare the wound bed, promoting the healing process. We describe four cases of traumatic, upper limb deep wounds caused by different physical and chemical agents, emphasising the effectiveness of treatment based on topical application of collagenase and hyaluronic acid (HA) before standardised surgical procedures. We performed careful disinfection of lesions combined with application of topical cream containing hyaluronic acid, bacterial fermented sodium hyaluronate (0·2%w/w) salt, and bacterial collagenase obtained from non-pathogenic Vibrio alginolyticus (>2·0 nkat1/g). In one patient a dermo-epidermal graft was used to cover the wide loss of substance. In two patients application of a HA-based dermal substitute was done. We obtained successful results in terms of wound healing, with satisfactory aesthetic result and optimal recovery of the affected limb functionality. Topical application of collagenase and HA, alone or before standardised surgical procedures allows faster wound healing. PMID:24698215

  8. Evaluation of the synergistic potential of vancomycin combined with other antimicrobial agents against methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus spp strains

    Directory of Open Access Journals (Sweden)

    Lívia Viganor da Silva

    2011-02-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA and coagulase-negative Staphylococcus spp (CNS are the most common pathogens that cause serious long term infections in patients. Despite the existence of new antimicrobial agents, such as linezolid, vancomycin (VAN remains the standard therapy for the treatment of infections caused by these multidrug-resistant strains. However, the use of VAN has been associated with a high frequency of therapeutic failures in some clinical scenarios, mainly with decreasing concentration of VAN. This work aims to evaluate the synergic potential of VAN plus sulfamethoxazole/trimethoprim (SXT, VAN plus rifampin (RIF and VAN plus imipenem (IPM in sub-minimum inhibitory concentrations against 22 clinical strains of MRSA and CNS. The checkerboard method showed synergism of VAN/RIF and VAN/SXT against two and three of the 22 strains, respectively. The combination of VAN with IPM showed synergistic effects against 21 out of 22 strains by the E-test method. Four strains were analyzed by the time-kill curve method and synergistic activity was observed with VAN/SXT, VAN/RIF and especially VAN/IPM in sub-inhibitory concentrations. It would be interesting to determine if synergy occurs in vivo. Evidence of in vivo synergy could lead to a reduction of the standard VAN dosage or treatment time.

  9. An ezetimibe-policosanol combination has the potential to be an OTC agent that could dramatically lower LDL cholesterol without side effects.

    Science.gov (United States)

    McCarty, Mark F

    2005-01-01

    Although many risk factors influence atherogenesis, LDL appears to play a primary role in this process. In prospective epidemiology, coronary risk increases as LDL cholesterol increases, throughout the entire range of concentrations encountered in healthy humans. Coronary risk is minimal in individuals and populations whose serum cholesterol remains quite low throughout life. Thus, practical strategies for achieving large reductions of LDL cholesterol in the general population could have a dramatic impact on coronary mortality rates. Dietary measures have limited potential in this regard; modest restriction of saturated fat has a rather trivial effect on LDL cholesterol, and the very-low-fat quasi-vegan diets that do have a notable effect in this regard currently have little appeal to the majority of the population. With respect to pharmacotherapy, most available hypolipidemic agents with reasonably potent activity entail side effects or compliance difficulties that would render their use too expensive or impractical for population-wide application. However, two agents may have great potential in this regard: policosanol and ezetimibe. The former, a mixture of long-chain alcohols derived from sugar cane wax, has effects on serum lipids comparable to those of statins, and may work by down-regulating expression of HMG-CoA reductase. However, unlike statins, policosanol appears to be devoid of side effects or risks. Ezetimibe is a newly approved drug that is a potent and highly specific inhibitor of an intestinal sterol permease; in daily doses as low as 10 mg, it suppresses intestinal absorption of cholesterol and decreases serum LDL cholesterol by approximately 18%. No side effects have been seen in clinical doses, and the fact that its hypolipidemic activity is additive to that of statins has generated considerable interest. Both policosanol and ezetimibe can be administered once daily. Future studies should determine whether policosanol, like statins, interacts

  10. Measurements of urinary kinins by HPLC-radioimmunoassay

    International Nuclear Information System (INIS)

    In this paper the authors describe a method for the individual determination of urinary kinins. Extraction from the urine is performed on an Amberlite CG-50 column and kinins are eluted with formic acid. The samples are further purified and kinins are separated by reversed phase HPLC. Bradykinin and lysylbradykinin are quantified by a sensitive radioimmunoassay capable of detecting 0.1 fmol of either peptide. Procedural losses are monitored by measuring the recovery of [3H]bradykinin and [3H]lysylbradykinin. Simple methods for labeling of bradykinin and lysylbradykinin with tritium are also presented. Recoveries of [3H]bradykinin and [3H]lysylbradykinin from biological material ranged between 77 and 91%. The combination of HPLC with radioimmunoassay makes it possible to determine kinin concentrations of biological samples with a higher sensitivity and greater specificity than previous methods. (Auth.)

  11. Development and Validation of a Novel Stability-Indicating RP-HPLC Method for the Simultaneous Determination of Related Substances of Ketoprofen and Omeprazole in Combined Capsule Dosage Form.

    Science.gov (United States)

    Koppala, Srinivasarao; Ranga Reddy, V; Anireddy, Jaya Shree

    2016-05-01

    A novel, simple, sensitive, selective and reproducible stability-indicating high performance liquid chromatographic method was developed for the quantitative determination of degradation products and process-related impurities of ketoprofen (KET) and omeprazole (OMZ) in combined oral solid dosage form. Chromatographic separation was achieved on a Phenomenex Luna C18 (2) column (150 × 4.6 mm, 5 μm) under gradient elution by using a binary mixture of potassium dihydrogen phosphate buffer and acetonitrile at a flow rate of 0.8 mL/min. Chromatogram was monitored at 233 nm for KET impurities and at 305 nm for OMZ impurities using a dual wavelength UV detector. Resolution for KET and OMZ and 14 impurities was found to be >1.5 for any pair of components. Typical retention behaviors of impurities at various pH values were depicted graphically. To prove the stability-indicating power of the method, the drug product was subjected to hydrolytic, oxidative, photolytic, humidity and thermal stress conditions as per ICH. The developed method was validated according to the current ICH guidelines for specificity, limit of detection, limit of quantification, linearity, accuracy, precision, ruggedness and robustness. PMID:26860397

  12. New micromethod to study the effect of antimicrobial agents on Toxoplasma gondii: comparison of sulfadoxine and sulfadiazine individually and in combination with pyrimethamine and study of clindamycin, metronidazole, and cyclosporin A.

    OpenAIRE

    Mack, D G; McLeod, R.

    1984-01-01

    An in vitro method by which reagents, cells, and Toxoplasma gondii trophozoites are conserved (micromethod) was developed to quantitate the effect of antimicrobial agents on T. gondii. Sulfadoxine alone had no effect on T. gondii in vitro when evaluated with a macromethod, the new micromethod, or visual inspection of Giemsa-stained preparations. Sulfadoxine combined with pyrimethamine inhibited T. gondii more than did pyrimethamine alone, but the combination of sulfadoxine plus pyrimethamine ...

  13. Development and application of a novel, dual-mode gradient, stability-indicating HPLC-DAD method for the simultaneous determination and purity assessment of mebeverine hydrochloride, diloxanide furoate and their corresponding major degradation products in combination with some gastrointestinal drugs in the form of oral doses.

    Science.gov (United States)

    Mabrouk, Mokhtar; El-Fatatry, Hamed; Hewala, Ismail; Emam, Ehab

    2013-09-01

    A simple, precise, rapid, stability-indicating reversed phase high performance liquid chromatographic method with photodiode array detection was developed and validated for the determination of mebeverine hydrochloride in combination with sulpiride or with diloxanide furoate and metronidazole in the presence of their corresponding degradation products. Optimum separation was achieved in less than 10 min using an X-Bridge C18 column (150 mm × 4.6 mm i.d., 3.5 μm particle size); elution was accomplished via the application of a dual-mode solvent and flow rate gradient system. This elution system enables the separation of nine components within a cycle time of 15 min and with a resolution greater than 2.5. Detection was conducted at 230 nm, and purity assessment was performed using a photodiode array detector. The method has been validated with respect to specificity, linearity, accuracy, precision, limit of quantitation, limit of detection, robustness and ruggedness. The validation criteria were met in all cases. The developed HPLC method was successfully applied to commercial tablets. It was shown that this method is very sensitive to the determination of the degradation products, downward to 0.1 w/w% levels, which is far below the limits for testing these degradation products within their corresponding intact drugs. PMID:23770637

  14. Feasibility Study of EndoTAG-1, a Tumor Endothelial Targeting Agent, in Combination with Paclitaxel followed by FEC as Induction Therapy in HER2-Negative Breast Cancer

    Science.gov (United States)

    Lemort, Marc; Wilke, Celine; Vanderbeeken, Marie-Catherine; D’Hondt, Veronique; De Azambuja, Evandro; Gombos, Andrea; Lebrun, Fabienne; Dal Lago, Lissandra; Bustin, Fanny; Maetens, Marion; Ameye, Lieveke; Veys, Isabelle; Michiels, Stefan; Paesmans, Marianne; Larsimont, Denis; Sotiriou, Christos; Nogaret, Jean-Marie; Piccart, Martine; Awada, Ahmad

    2016-01-01

    Background EndoTAG-1, a tumor endothelial targeting agent has shown activity in metastatic triple-negative breast cancer (BC) in combination with paclitaxel. Methods HER2-negative BC patients candidates for neoadjuvant chemotherapy were scheduled to receive 12 cycles of weekly EndoTAG-1 22mg/m2 plus paclitaxel 70mg/m2 followed by 3 cycles of FEC (Fluorouracil 500mg/m2, Epirubicin 100mg/m2, Cyclophosphamide 500mg/m2) every 3 weeks followed by surgery. Primary endpoint was percent (%) reduction in Magnetic Resonance Imaging (MRI) estimated Gadolinium (Gd) enhancing tumor volume at the end of EndoTAG-1 plus paclitaxel administration as compared to baseline. Safety, pathological complete response (pCR) defined as no residual tumor in breast and axillary nodes at surgery and correlation between % reduction in MRI estimated tumor volume and pCR were also evaluated. Results Fifteen out of 20 scheduled patients were included: Six patients with estrogen receptor (ER)-negative/HER2-negative and 9 with ER-positive/HER2-negative BC. Nine patients completed treatment as per protocol. Despite premedication and slow infusion rates, grade 3 hypersensitivity reactions to EndoTAG-1 were observed during the 1st, 2nd, 3rd and 6th weekly infusion in 4 patients, respectively, and required permanent discontinuation of the EndoTAG-1. Moreover, two additional patients stopped EndoTAG-1 plus paclitaxel after 8 and 9 weeks due to clinical disease progression. Two patients had grade 3 increases in transaminases and 1 patient grade 4 neutropenia. pCR was achieved in 5 of the 6 ER-/HER2- and in none of the 9 ER+/HER2- BC patients. The mean % reduction in MRI estimated tumor volume at the end of EndoTAG-1 plus paclitaxel treatment was 81% (95% CI, 66% to 96%, p<0.001) for the 15 patients that underwent surgery; 96% for patients with pCR and 73% for patients with no pCR (p = 0.04). Conclusions The EndoTAG-1 and paclitaxel combination showed promising preliminary activity as preoperative treatment

  15. Feasibility Study of EndoTAG-1, a Tumor Endothelial Targeting Agent, in Combination with Paclitaxel followed by FEC as Induction Therapy in HER2-Negative Breast Cancer.

    Directory of Open Access Journals (Sweden)

    Michail Ignatiadis

    Full Text Available EndoTAG-1, a tumor endothelial targeting agent has shown activity in metastatic triple-negative breast cancer (BC in combination with paclitaxel.HER2-negative BC patients candidates for neoadjuvant chemotherapy were scheduled to receive 12 cycles of weekly EndoTAG-1 22mg/m2 plus paclitaxel 70mg/m2 followed by 3 cycles of FEC (Fluorouracil 500mg/m2, Epirubicin 100mg/m2, Cyclophosphamide 500mg/m2 every 3 weeks followed by surgery. Primary endpoint was percent (% reduction in Magnetic Resonance Imaging (MRI estimated Gadolinium (Gd enhancing tumor volume at the end of EndoTAG-1 plus paclitaxel administration as compared to baseline. Safety, pathological complete response (pCR defined as no residual tumor in breast and axillary nodes at surgery and correlation between % reduction in MRI estimated tumor volume and pCR were also evaluated.Fifteen out of 20 scheduled patients were included: Six patients with estrogen receptor (ER-negative/HER2-negative and 9 with ER-positive/HER2-negative BC. Nine patients completed treatment as per protocol. Despite premedication and slow infusion rates, grade 3 hypersensitivity reactions to EndoTAG-1 were observed during the 1st, 2nd, 3rd and 6th weekly infusion in 4 patients, respectively, and required permanent discontinuation of the EndoTAG-1. Moreover, two additional patients stopped EndoTAG-1 plus paclitaxel after 8 and 9 weeks due to clinical disease progression. Two patients had grade 3 increases in transaminases and 1 patient grade 4 neutropenia. pCR was achieved in 5 of the 6 ER-/HER2- and in none of the 9 ER+/HER2- BC patients. The mean % reduction in MRI estimated tumor volume at the end of EndoTAG-1 plus paclitaxel treatment was 81% (95% CI, 66% to 96%, p<0.001 for the 15 patients that underwent surgery; 96% for patients with pCR and 73% for patients with no pCR (p = 0.04.The EndoTAG-1 and paclitaxel combination showed promising preliminary activity as preoperative treatment, especially in ER-/HER2

  16. Expermental Studies of quantitative evaluation using HPLC

    Directory of Open Access Journals (Sweden)

    Ki Rok Kwon

    2005-06-01

    Full Text Available Methods : This study was conducted to carry out quantitative evaluation using HPLC Content analysis was done using HPLC Results : According to HPLC analysis, each BVA-1 contained approximately 0.36㎍ melittin, and BVA-2 contained approximately 0.54㎍ melittin. But the volume of coating was so minute, slight difference exists between each needle. Conclusion : Above results indicate that the bee venom acupuncture can complement shortcomings of syringe usage as a part of Oriental medicine treatment, but extensive researches should be done for further verification.

  17. HPLC for quality control of polyimides

    Science.gov (United States)

    Young, P. R.; Sykes, G. F.

    1979-01-01

    High Pressure Liquid Chromatography (HPLC) as a quality control tool for polyimide resins and prepregs are presented. A data base to help establish accept/reject criteria for these materials was developed. This work is intended to supplement, not replace, standard quality control tests normally conducted on incoming resins and prepregs. To help achieve these objectives, the HPLC separation of LARC-160 polyimide precursor resin was characterized. Room temperature resin aging effects were studied. Graphite reinforced composites made from fresh and aged resin were fabricated and tested to determine if changes observed by HPLC were significant.

  18. HPLC-SPE-NMR for combinatorial biosynthetic investigations – Expanding the landscape of diterpene structural diversity

    DEFF Research Database (Denmark)

    Kongstad, Kenneth Thermann; Andersen-Ranberg, Johan; Hamberger, Björn Robert;

    In this work, the analytical technique, HPLC-HRMS-SPE-NMR was used for the first time in combination with combinatorial biosynthetic investigations in N. benthamiana. This efficient setup allowed for identification of several diterpene synthase (diTPS) combinations responsible for stereospecific...

  19. Bioreductive alkylating agent porfiromycin in combination with radiation therapy for the management of squamous cell carcinoma of the head and neck.

    Science.gov (United States)

    Haffty, B G; Son, Y H; Wilson, L D; Papac, R; Fischer, D; Rockwell, S; Sartorelli, A C; Ross, D; Sasaki, C T; Fischer, J J

    1997-01-01

    Porfiromycin (methyl mitomycin C) has been shown in laboratory studies to have increased preferential cytotoxicity to hypoxic cells and therefore may provide enhanced therapeutic efficacy over mitomycin C when used in combination with radiation therapy (RT). The purpose of the two clinical studies reported here is to evaluate the concomitant use of porfiromycin with RT in the management of squamous cell carcinoma of the head and neck. Between October 1989 and July 1992, 21 patients presenting with locally advanced stage III/IV squamous cell carcinoma of the head and neck were entered into a phase I toxicity trial evaluating porfiromycin as an adjunct to RT. Patients were eligible if they had biopsy documented squamous cell carcinoma of the head and neck with a low probability of cure by conventional means. Patients were treated with standard fractionated daily RT to a total median dose of 63 Gy, with porfiromycin administered on days 5 and 47 of the course of RT. Upon completion of this phase I trial, a phase III trial was initiated in November 1992 randomizing patients with squamous cell carcinoma of the head and neck to RT with mitomycin C vs. RT with porfiromycin. There is no radiation only arm in this current trial. To date, 75 patients have been entered on this trial and acute toxicity data are available on 67 patients (34 porfiromycin, 31 mitomycin C) who have completed their entire course of treatment. Median follow-up of the 21 patients enrolled in the phase I porfiromycin trial is 58.5 months. Of the 21 patients, 5 were treated at a dose of 50 mg/M2, 4 at 45 mg/M2, and the final 12 at 40 mg/M2, which appeared to result in acceptable acute hematological and nonhematological toxicities. As of December 1995, 14 of the 21 patients have died with disease and 7 remain alive and free of disease, resulting in a 5-year actuarial survival of 32%. Of the patients enrolled to date in the phase III randomized trial of mitomycin C vs. porfiromycin, there have been no

  20. TLC and HPLC methods to follow the synthesis of vinorelbine.

    Science.gov (United States)

    Chunfang, Zhao; Yin, Xiong; Longjiang, Yu; Shuo, Li; Zeqiang, Wu

    2010-09-01

    The thin-layer chromatography (TLC) combined with high-performance liquid chromatography (HPLC) has been proved to be a quick and valid method to detect the intermediates and the end-product created during the chemosynthesis process of vinorelbine (VB). This paper gives a detailed investigation on the results of two determination methods when the condition of the detection changed. It shows that when TLC developer is consisted of petroleum ether, chloroform, acetone, and diethyl amine (23.5:12:2:2.5, v/v/v/v), vinblastine sulfate (VBS), anhydrovinblastine (AHVB), and VB can be separated specifically. When the mobile phase of HPLC is a mixture of methyl alcohol, acetonitrile, diethyl amine, and high purity water (420:252:3:225; v/v/v/v), adjusted with orthophosphoric acid to pH 6.5, the intermediates and the resultants of the chemosynthesis of VB can be determined effectively. It can also be used to fix quantify of the resultants. The calibration curve for VB shows good linearity in the two mass concentration ranges of 0.0100-0.0500 mg/mL (r = 0.9956) and 0.00600-0.0100 mg/mL (r = 0.9978), respectively. The limit of detection of HPLC for VB is 0.200 microg/mL. PMID:20819300

  1. Radiographic scintiscanning agent

    International Nuclear Information System (INIS)

    A new technetium-based scintiscanning agent has been prepared comprising a water soluble sup(99m)Tc-methanehydroxydiphosphonate in combination with a reducing agent selected from stannous, ferrous, chromous and titanous salts. As an additional stabilizer salts and esters of gentisic or ascorbic acids have been used. (E.G.)

  2. Uncertainty Determination of Sugar in Pepsin by HPLC-RI%HPLC-RI法测定胃蛋白酶中糖的不确定度评定

    Institute of Scientific and Technical Information of China (English)

    谢贞建; 颜军; 何钢; 苟小军

    2011-01-01

    A mathematic model using HPLC-RI for the uncertainty determination of sugar content in pepsin was established to analyze the factors which affect the uncertainty.Each component of factors was evaluated to calculate combined uncertainty.The combined standard uncertainty and the expanded uncertainty were finally obtained by synthesizing the uncertainties of various component variables.The findings show that the combined standard uncertainty is 1.92% and the expanded uncertainty is 4.1%.It is concluded that this method is applicable to the uncertainty analysis in the determination of sugar in pepsin by HPLC-RI method.%通过建立HPLC-RI法测定胃蛋白酶中糖含量的数学模型,找出影响不确定度的因素,并对各个影响不确定度的因素进行评估、计算,由此计算出合成标准不确定度和扩展不确定度.实验结果的合成标准不确定度为1.92%,扩展不确定度为4.1%,表明HPLC-RI法测定胃蛋白酶中糖的不确定度评定结果可靠.

  3. Hyperthermia and chemotherapy agent

    International Nuclear Information System (INIS)

    The use of chemotherapeutic agents for the treatment of cancer dates back to the late 19th century, but the modern era of chemotherapy drugs was ushered in during the 1940's with the development of the polyfunctional alkylating agent. Since then, numerous classes of drugs have evolved and the combined use of antineoplastic agents with other treatment modalities such as radiation or heat, remains a large relatively unexplored area. This approach, combining local hyperthermia with chemotherapy agents affords a measure of targeting and selective toxicity not previously available for drugs. In this paper, the effects of adriamycin, bleomycin and cis-platinum are examined. The adjuvant use of heat may also reverse the resistance of hypoxic cells noted for some chemotherapy agents

  4. An improved extraction method for the HPLC determination of morphine and its metabolites in plasma.

    Science.gov (United States)

    Pawula, M; Barrett, D A; Shaw, P N

    1993-01-01

    A new, simple and rapid extraction procedure coupled with a combined coulometric-fluorescence HPLC assay is described for the simultaneous determination of morphine (M) and morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G), and normorphine (NM) in plasma. The effect of concentration and pH of selected ion-pairing agents on the extraction of these compounds from plasma by solid-phase extraction was investigated. The extraction procedure was optimized in terms of recovery, reproducibility and lack of interference from endogenous materials. The optimized method uses tetrabutylammonium hydrogen sulphate (TBAHS) at pH 10 followed by separation on a single C18 solid-phase extraction cartridge. For routine analysis the procedure provides high and reproducible recoveries over a concentration range of 1.0-1000 ng ml-1 for morphine, M6G and normorphine and 20-1000 ng ml-1 for M3G. The method was used successfully to analyse plasma samples from a pharmacokinetic study in which sheep had received an intravenous dose of 0.015 mg kg-1 of M6G. PMID:8357878

  5. Determination of Bisphenol A in Infusion Used Combined Cover and Bisphenol A Migration into Infusion by HPLC%输液袋用聚碳酸酯组合盖中双酚A含量及双酚A向输液中迁移量的测定

    Institute of Scientific and Technical Information of China (English)

    王丹丹; 金宏

    2012-01-01

    目的 建立输液袋用聚碳酸酯组合盖中双酚A含量及双酚A向输液中迁移量的高效液相色谱测定法.方法 采用Diamosil-C18(4.6 mm×250 mm,5μm)色谱柱;流动相为甲醇-水(80∶20),检测波长为227 nm,流速1.0 mL·min-1.结果 双酚A在1.354~27.08 ng内呈良好的线性关系(r=0.9999);聚碳酸酯组合盖中双酚A含量和双酚A向输液中迁移量测定的平均回收率分别为91.7%(RSD=2.3%)和93.9%(RSD=1.8%).结论 该方法准确、灵敏、简便,适用于对输液袋用聚碳酸酯组合盖中双酚A含量及双酚A向输液中迁移量的测定.%OBJECTIVE To develop a method for determination of bisphenol A in Infusion Used Combined Cover and bisphenol A migration into infusion by HPLC. METHODS A Diamosil-C18column(4.6 mm×250 mm, 5 μm) and a DAD detector was adopted with methanol and water(80 : 20) as mobile phase. The wavelength was 227 nm, the flow rate was 1.0 mL·min‐1. RESULTS The method had a linear range in 1.354-27.08 ng (r=0.999 9). The average recovery of bisphenol A and bisphenol A migration was 91.7%(RSD=2.3%) and 93.9%(RSD=1.8%), respectively. CONCLUSION This method is accurate, sensitive, simple, and can be used for determination of bisphenol A and bisphenol A migration into infusion from Infusion Used Combined Cover.

  6. Determination of CMPO using HPLC -UV

    Energy Technology Data Exchange (ETDEWEB)

    Gracy Elias; Gary S. Groenewold; Bruce J. Mincher; Stephen P. Mezyk

    2012-06-01

    Octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) is an extractant proposed for selective separation of radionuclide metals from used nuclear fuel solutions using solvent extraction. Radiolysis reactions can degrade CMPO and reduce separation performance and hence methods for measuring concentration of CMPO and identifying degradation products are needed. A novel high performance liquid chromatography (HPLC) method employing ultraviolet detection (UV) was developed to detect and quantitate CMPO in dodecane. Some radiolysis products in gamma and alpha irradiated CMPO solutions were identified using HPLC/electrospray ionization-mass spectrometry (ESI-MS). Validation data indicated that the HPLC-UV method for CMPO determination provided good linearity, sensitivity, procedure accuracy and system precision. CMPO-nitric acid complexes were also identified, that account for the apparent loss of CMPO in acidic environment, independent of irradiation.

  7. Antistaphylococcal Activity of ACHN-490 Tested Alone and in Combination with Other Agents by Time-Kill Assay ▿ † ‡

    OpenAIRE

    Lin, Gengrong; Ednie, Lois M.; Appelbaum, Peter C.

    2010-01-01

    Synergy time-kill studies of 47 methicillin-resistant Staphylococcus aureus strains with differing resistance phenotypes showed that combinations of subinhibitory concentrations of ACHN-490 and daptomycin yielded synergy against 43/47 strains at 24 h, while the combination was indifferent against the remaining 4 strains. ACHN-490 and ceftobiprole showed synergy in 17/47 strains tested at 24 h, while 6/47 strains showed synergy for subinhibitory combinations of ACHN-490 and linezolid.

  8. 植物鞣剂与非铬金属鞣剂结合鞣制的研究%Vegetable and Non-chromium Metal Tanning Agent Combination Tannage

    Institute of Scientific and Technical Information of China (English)

    李闻欣; 王勇

    2013-01-01

    用栲胶、铝鞣剂、钛鞣剂对浸酸猪皮进行结合鞣制,在最佳工艺的基础上,选取与铝鞣剂和钛鞣剂搭配最佳的栲胶,考察栲胶用量和改变结合鞣不同鞣制阶段pH值对Ts的影响.结果表明:使用水解类栲胶的效果一般情况下比用缩合类栲胶好,且用栗木栲胶的效果更好.在植铝钛结合鞣中,栗木栲胶用量15%,当植鞣pH值为4.8、铝鞣pH值为3.0、钛鞣pH值为1.5时,结合鞣制革的Ts达到93℃.%The pickling pigskins were tanned with vegetable tannin, aluminium tanning agent and titanium tanning agent ( self - made). On the basis of the optimum, the best collocation of tannin extracts was selected with aluminium tanning agent and titanium tanning agent. The effect of tannin extract dosage and different pH value in combination tanning process on Ts were investigated. The results show the tanning properties of the pelts by hydrolysable tannin are better than that by the condensed tannin on general circumstances, and chestnut extract tannin has a better tanning effect than other tannins. In the vegetable - alumium - titanium combination tanning process, the amount of chestnut extract is 15% , when the pH value of vegetable tannage is 4. 8, the pH value of the aluminum tannage is 3. 0, the pH value of the titanium tannage is 1. 5, the maximum Ts value of the combination tanned leather can be up to 931.

  9. Determination of amphetamine by HPLC after acetylation.

    Science.gov (United States)

    Veress, T

    2000-01-01

    An analytical procedure has been developed for the HPLC determination of amphetamine by off-line pre-column derivatization. The proposed procedure consists of sample preparation by acetylation of amphetamine with acetic anhydride and a subsequent reversed-phase HPLC separation on an octadecyl silica stationary phase with salt-free mobile phase (tetrahydrofuran, acetonitrile, 0.1% triethylamine in water, 15:15:70 v/v) applying UV-detection. The applicability of the elaborated procedure is demonstrated with results obtained by analysis of real samples seized in the Hungarian black market. PMID:10641931

  10. A novel enzymatically-mediated drug delivery carrier for bone tissue engineering applications: combining biodegradable starch-based microparticles and differentiation agents

    OpenAIRE

    Balmayor, Elizabeth Rosado; Tuzlakoglu, K.; Marques, A.P.; Azevedo, Helena S.; Reis, R.L.

    2008-01-01

    In many biomedical applications, the performance of biomaterials depends largely on their degradation behavior. For instance, in drug delivery applications, the polymeric carrier should degrade under physiological conditions slowly releasing the encapsulated drug. The aim of this work was, therefore, to develop an enzymaticmediated degradation carrier system for the delivery of differentiation agents to be used in bone tissue engineering applications. For that, a polym...

  11. Agent engineering

    CERN Document Server

    Liu, Jiming; Zhong, Ning; Wang, Patrick S P

    2001-01-01

    Agent engineering concerns the development of autonomous computational or physical entities capable of perceiving, reasoning, adapting, learning, cooperating and delegating in a dynamic environment. It is one of the most promising areas of research and development in information technology, computer science and engineering. This book addresses some of the key issues in agent engineering: What is meant by "autonomous agents"? How can we build agents with autonomy? What are the desirable capabilities of agents with respect to surviving (they will not die) and living (they will furthermore enjoy

  12. ISOCRATIC SEPARATION OF FOUR BETA BLOCKERS WITH AMLODIPINE BY C18 RP-HPLC: APPLICATION TO AMLODIPINE DETERMINATION IN PHARMACEUTICAL DOSAGE FORMS

    OpenAIRE

    Panchumarthy Ravisankar; Garikapati Devala Rao

    2013-01-01

    This method described for the successful separation of a beta blockers with amlodipine by RP-HPLC on a C18 column with UV detection. One of the key goals of High Performance Liquid Chromatography technique is to achieve a consistent and reproducible separation. A simple, precise, selective and sensitive HPLC method was developed and validated for determination of five anti-hypertensive agents, atenolol hydrochloride, metoprolol succinate, propranolol hydrochloride, amlodipine besylate and neb...

  13. Multi-components determination by single reference standard and HPLC fingerprint analysis for Lamiophlomis rotata Pill.

    Science.gov (United States)

    Chen, Jing; Wang, Yang; Sun, Guoxiang; Ma, Yongfu; Guo, Xingjie

    2016-07-01

    A validated HPLC method was developed to evaluate the quality of Lamiophlomis rotata Pill combining the multi-components analysis by single reference standard with HPLC fingerprint analysis. Five bioactive components (shanzhiside methyl ester, loganin, 8-O-acetylshanzhiside methyl ester, forsythoside B and luteolin-7-O-β-D-glucopyranoside) were selected as markers to control the quality of L. rotata Pill. The results revealed that the chromatographic fingerprint method coupled with multi-components analysis provides an effective and feasible way to determine the components in L. rotata Pill. PMID:26595778

  14. An Inexpensive Digital Gradient Controller for HPLC.

    Science.gov (United States)

    Brady, James E.; Carr, Peter W.

    1983-01-01

    Use of gradient elution techniques in high performance liquid chromatography (HPLC) is often essential for direct separation of complex mixtures. Since most commercial controllers have features that are of marginal value for instructional purposes, a low-cost controller capable of illustrating essential features of gradient elution was developed.…

  15. Combined radiation-protective and radiation-sensitizing agents. II. Radiosensitivity of hypoxic or aerobic Chinese hamster fibroblasts in the presence of cysteamine and misonidazole: implications for the oxygen effect with Appendix on calculation of dose-modifying factors

    International Nuclear Information System (INIS)

    Experiments have been done to test whether a hypoxic cell radiosensitizing agent (misonidazole) can be combined with a radioprotecting agent (cysteamine) to equalize partially the radiation response of hypoxic and aerobic mammalian cells in tissue culture. The results indicate that cysteamine will protect against the radiosensitization of a hypoxic cell sensitizing drug (2.5 mM misonidazole) at much lower concentration than it will protect against the radiosensitization of oxygen (350 μM). Thus the addition of a radiation-protective drug tends to cancel the drug benefit of the radiosensitizer and therefore increases the differential response of hypoxic and aerobic cells rather than equalizing this response. The data suggest that even in situations where tumor tissue absorbs far less radioprotective drug than normal tissue (e.g., WR 2721), one might expect difficulties with the simultaneous administration of radiosensitizing and radioprotecting drugs

  16. Single-agent therapy with sorafenib or 5-FU is equally effective in human colorectal cancer xenograft—no benefit of combination therapy

    OpenAIRE

    Wehler, Thomas C.; Hamdi, Swaantje; Maderer, Annett; Graf, Claudine; Gockel, Ines; Schmidtmann, Irene; Hainz, Michael; Berger, Martin R; Theobald, Matthias; Galle, Peter R.; Moehler, Markus; Schimanski, Carl C

    2012-01-01

    Background We initiated this preclinical study in order to analyze the impact of sorafenib single treatment versus combination treatment in human colorectal cancer. Methods The effect of increasing sorafenib doses on proliferation, apoptosis, migration, and activation of signal cascades was analyzed in vitro. The effect of sorafenib single treatment versus 5-fluorouracil (5-FU) single treatment and combination therapy on in vivo proliferation and target cytokine receptor/ligand expression was...

  17. Radioactive scanning agents with stabilizer

    International Nuclear Information System (INIS)

    Stable compositions useful as technetium 99-based scintigraphic agents comprise gentisyl alcohol or a pharmaceutically-acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in pertechnetate-99m (sup(99m)TcOsub(4)sup(-)) solution. The compositions are especially useful in combination with a phosphate or phosphonate material that carries the radionuclide to bone, thus providing a skeletal imaging agent

  18. Chemical fingerprint analysis for quality control and identification of Ziyang green tea by HPLC.

    Science.gov (United States)

    He, Xiaoye; Li, Jianke; Zhao, Wei; Liu, Run; Zhang, Lin; Kong, Xianghong

    2015-03-15

    A simple and reliable HPLC fingerprint method was developed and validated for the quality control and identification of Ziyang green tea. Ten batches of Ziyang green tea collected from different plantations in Shaanxi Ziyang of China were used to establish the fingerprint. The feasibility and advantages of the used HPLC fingerprint were verified for its similarity evaluation by systematically comparing chromatograms with professional analytical software recommended by State Food and Drug Administration (SFDA) of China. The similarities of the fingerprints of 10 batches of tea samples were all more than 0.981. Additionally, simultaneous quantification of 10 major bioactive ingredients in the tea samples was conducted to interpret the consistency of the quality test. The results indicated that the HPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantification analysis can be successfully used to assess the quality and to identify the authenticity of Ziyang green tea. PMID:25308687

  19. SPE-HPLC purification of endocrine disrupting compounds from human serum for assessment of xenoestrogenic activity

    DEFF Research Database (Denmark)

    Hjelmborg, P.S.; Ghisari, Mandana; Bonefeld-Jørgensen, Eva

    2006-01-01

    Assessment of xenoestrogenic activity in human serum samples requires the removal of endogenous sex hormones to assure that the activity measured originates from xenobiotic compounds only. Serum samples representing high, medium and lower accumulation of persistent organic pollutants (POPs) were...... extracted using solid-phase extraction (SPE) followed by normal-phase high-performance liquid chromatography (NP-HPLC) for separation of POPs from endogenous hormones. The recovery of polychlorinated biphenyl (PCB) congeners in spiked serum samples was up to 86 %, making the extraction method suitable...... response curve. 17β-Estradiol titrations showed that the xenoestrogenic effects were mediated via ER. Moreover, our SPE-HPLC-ERE-CALUX assay was demonstrated to elicit high interlaboratory correlation. In the present study the combination of SPE-HPLC purification and the ex vivo estrogenic responses...

  20. Programming Service Oriented Agents

    OpenAIRE

    Hirsch, Benjamin; Konnerth, Thomas; Burkhardt, Michael; Albayrak, Sahin

    2010-01-01

    This paper introduces a programming language for service-oriented agents. JADL++ combines the ease of use of scripting-languages with a state-of-the-art service oriented approach which allows the seamless integration of web-services. Furthermore, the language includes OWL-based ontologies for semantic descriptions of data and services, thus allowing agents to make intelligent decisions about service calls.

  1. A randomised, phase II trial of the DNA-hypomethylating agent 5-aza-2′-deoxycytidine (decitabine) in combination with carboplatin vs carboplatin alone in patients with recurrent, partially platinum-sensitive ovarian cancer

    Science.gov (United States)

    Glasspool, R M; Brown, R; Gore, M E; Rustin, G J S; McNeish, I A; Wilson, R H; Pledge, S; Paul, J; Mackean, M; Hall, G D; Gabra, H; Halford, S E R; Walker, J; Appleton, K; Ullah, R; Kaye, S

    2014-01-01

    Background: Our previous laboratory and clinical data suggested that one mechanism underlying the development of platinum resistance in ovarian cancer is the acquisition of DNA methylation. We therefore tested the hypothesis that the DNA hypomethylating agent 5-aza-2′-deoxycytodine (decitabine) can reverse resistance to carboplatin in women with relapsed ovarian cancer. Methods: Patients progressing 6–12 months after previous platinum therapy were randomised to decitabine on day 1 and carboplatin (AUC 6) on day 8, every 28 days or carboplatin alone. The primary objective was response rate in patients with methylated hMLH1 tumour DNA in plasma. Results: After a pre-defined interim analysis, the study closed due to lack of efficacy and poor treatment deliverability in 15 patients treated with the combination. Responses by GCIG criteria were 9 out of 14 vs 3 out of 15 and by RECIST were 6 out of 13 vs 1 out of 12 for carboplatin and carboplatin/decitabine, respectively. Grade 3/4 neutropenia was more common with the combination (60% vs 15.4%) as was G2/3 carboplatin hypersensitivity (47% vs 21%). Conclusions: With this schedule, the addition of decitabine appears to reduce rather than increase the efficacy of carboplatin in partially platinum-sensitive ovarian cancer and is difficult to deliver. Patient-selection strategies, different schedules and other demethylating agents should be considered in future combination studies. PMID:24642620

  2. Combined effects of tirapazamine and mild hyperthermia on anti-angiogenic agent (TNP-470) treated tumors--reference to the effect on intratumor quiescent cells

    International Nuclear Information System (INIS)

    Purpose: To evaluate the efficacy of the use of tirapazamine (TPZ), especially combined with mild hyperthermia (40 deg. C, 60 min), in the treatment of solid tumors following an anti-angiogenic treatment with TNP-470. In addition, we assessed the effect of TPZ and/or mild hyperthermia (MHT) combined with conventional radiotherapy or chemotherapy on TNP-470 treated tumors. Materials and Methods: C3H/He mice bearing SCC VII tumors subcutaneously received TNP-470 at two doses of 100 mg/kg after tumor cell inoculation. At the same time, the tumor-bearing mice received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received TPZ administration combined with or without MHT, no. gammano. -ray irradiation combined with or without TPZ and/or MHT, or cisplatin injection with or without TPZ and/or MHT. Another group of mice received a series of test doses of no. gammano. -rays while alive or after being killed to obtain hypoxic fractions (HFs) in the tumors at various time points after the above-mentioned cytotoxic treatment point. After each treatment, the tumors were excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (or quiescent [Q] cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P + Q) tumor cells was determined from the tumors that were not pretreated with BrdU. For the measurement of the HFs, the MN frequency of BrdU-unlabeled cells was then used to calculate the surviving fraction of the unlabeled cells from the regression line for the relationship between the MN frequency and the surviving fraction of total tumor cells. Results: TPZ administration combined with TNP-470 treatment and MHT increased the MN frequency more markedly than treatment with TPZ alone, and this tendency was

  3. Decomposition dynamic of higher plant pigments by HPLC analysis

    Institute of Scientific and Technical Information of China (English)

    LUO Yi; ZHANG Ting-zhou; ZHOU Qi-xing; MAO Da-qing; WAN Dong-mei

    2004-01-01

    The fate of the litter of dominant vegetation(willows and reeds) is one of the aspects studied in the frame of the project "Onderzoek Milieu Effecten Sigmaplan". One of the questions to be considered is how long the litter stays within the estuary. In this paper, the time the leaf litter(Salix triandra and Phragmites australis) stayed in the Schelde estuary was studied by using plant pigment as biomarkers with HPLC application. After analyzing the original data from the incubation experiment described by Dubuison and Geers(1999), the decomposition dynamics patterns of pigments were analyzed and described, and these decomposition dynamics patterns were used as calibration patterns. By using Spearman Rank Order Correlation, the calibration patterns of the pigments which were significant(p<0.05) were grouped. In this way, several groups of the calibration patterns of pigment decomposition were achieved. The presence or absence of these groups of pigments (whether they can be detected or not from HPLC) was shown to be useful in determining the time the litter has stayed in the water. Combining data of DW and POC, more precise timing can be obtained.

  4. Rosiglitazone evaluated for cardiovascular outcomes in oral agent combination therapy for type 2 diabetes (RECORD): a multicentre, randomised, open-label trial

    DEFF Research Database (Denmark)

    Home, Philip D; Pocock, Stuart J; Beck-Nielsen, Henning;

    2009-01-01

    BACKGROUND: Rosiglitazone is an insulin sensitiser used in combination with metformin, a sulfonylurea, or both, for lowering blood glucose in people with type 2 diabetes. We assessed cardiovascular outcomes after addition of rosiglitazone to either metformin or sulfonylurea compared with the comb...

  5. Eicosapentaenoic Acid Inhibits Oxidation of ApoB-containing Lipoprotein Particles of Different Size In Vitro When Administered Alone or in Combination With Atorvastatin Active Metabolite Compared With Other Triglyceride-lowering Agents.

    Science.gov (United States)

    Mason, R Preston; Sherratt, Samuel C R; Jacob, Robert F

    2016-07-01

    Eicosapentaenoic acid (EPA) is a triglyceride-lowering agent that reduces circulating levels of the apolipoprotein B (apoB)-containing lipoprotein particles small dense low-density lipoprotein (sdLDL), very-low-density lipoprotein (VLDL), and oxidized low-density lipoprotein (LDL). These benefits may result from the direct antioxidant effects of EPA. To investigate this potential mechanism, these particles were isolated from human plasma, preincubated with EPA in the absence or presence of atorvastatin (active) metabolite, and subjected to copper-initiated oxidation. Lipid oxidation was measured as a function of thiobarbituric acid reactive substances formation. EPA inhibited sdLDL (IC50 ∼2.0 μM) and LDL oxidation (IC50 ∼2.5 μM) in a dose-dependent manner. Greater antioxidant potency was observed for EPA in VLDL. EPA inhibition was enhanced when combined with atorvastatin metabolite at low equimolar concentrations. Other triglyceride-lowering agents (fenofibrate, niacin, and gemfibrozil) and vitamin E did not significantly affect sdLDL, LDL, or VLDL oxidation compared with vehicle-treated controls. Docosahexaenoic acid was also found to inhibit oxidation in these particles but over a shorter time period than EPA. These data support recent clinical findings and suggest that EPA has direct antioxidant benefits in various apoB-containing subfractions that are more pronounced than those of other triglyceride-lowering agents and docosahexaenoic acid. PMID:26945158

  6. Antibiotic Agents

    Science.gov (United States)

    ... either as public health or as non-public health antimicrobial agents. What is the difference between bacteriostats, sanitizers, disinfectants ... bacteria, however, there is considerable controversy surrounding their health benefits. The ... producing agents (Table of Antibacterials) have been used for many ...

  7. Determination of some psychotropic drugs in serum and saliva samples by HPLC-DAD and HPLC MS.

    Science.gov (United States)

    Petruczynik, A; Wróblewski, K; Szultka-Młyńska, M; Buszewski, B; Karakuła-Juchnowicz, H; Gajewski, J; Morylowska-Topolska, J; Waksmundzka-Hajnos, M

    2016-08-01

    A simple, rapid and sensitive HPLC-DAD method has been developed and validated for the simultaneous determination of seven psychotropic drugs (risperidone, citalopram, clozapine,quetiapine, levomepromazine, perazine and aripiprazole) in human serum or saliva samples. The chromatographic analyses were performed on a XSELECT CSH Phenyl-Hexyl column with a mobile phase containing methanol, acetate buffer at pH 3.5 and 0.025mL(-1) diethylamine. The influence of concentration of methanol in injection samples and injection volume on peak symmetry and system efficiency was examined.The full separation of all investigated drugs, good peaks' symmetry and simultaneously high systems efficiency were obtained in applied chromatographic system. The method is suitable for the analysis of investigated drugs in human plasma or saliva for psychiatric patients for control of pharmacotherapy, particularly in combination therapy. HPLC-MS was applied for verification of the presence of drugs and their metabolites in serum and saliva samples from patients. PMID:26809494

  8. STABILITY INDICATING HPLC METHOD DEVELOPMENT: A REVIEW

    Directory of Open Access Journals (Sweden)

    Bhoomi P. Shah*, Suresh Jain, Krishna K. Prajapati and Nasimabanu Y. Mansuri

    2012-09-01

    Full Text Available High performance liquid chromatography is one of the most accurate methods widely used for the quantitative as well as qualitative analysis of drug product and is used for determining drug product stability. Stability indicating HPLC methods are used to separate various drug related impurities that are formed during the synthesis or manufacture of drug product. This article discusses the strategies and issues regarding the development of stability indicating HPLC system for drug substance. A number of key chromatographic factors were evaluated in order to optimize the detection of all potentially relevant degradants. The method should be carefully examined for its ability to distinguish the primary drug components from the impurities. New chemical entities and drug products must undergo forced degradation studies which would be helpful in developing and demonstrating the specificity of such stability indicating methods. At every stage of drug development practical recommendations are provided which will help to avoid failures.

  9. HPLC/MS Fingerprint Analysis of Tangshenosides

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Radix codonopsis(党参),which is derived fromCodonopsis pilosula, C.pilosula subsp. Modesta andC. Tangshen(ChP,2000),has been used as a remedy fora decrease of appetite, psychoneurosis, fatigue, dyspepsiaetc.or as a substitute for Panax ginseng in traditionalChinese medicine. Relating to the constituents of theseherbs, triterpenes, phytosterols, furaldehyde, sesquitesand some phenolic glycosides have been reported, butnone of these compounds seems to be responsible for thebiological activities of this drug. As regards the quality evaluation of Radix Codonopsis, a HPLC analysis of atractylenolide Ⅲ has been described, but this sesquiterpene lactone exists in a very low content and is difficultfor conventional analysis. The determination of polysaccharide also met limitation because of its non-specialization. In this paper, we report the HPLC/MS fingerprintsanalysis of phelolic glycosides from Radix Codonopsis including three species.

  10. Effectiveness and mode of action of a combination therapy for heterotopic ossification with a retinoid agonist and an anti-inflammatory agent.

    Science.gov (United States)

    Sinha, Sayantani; Uchibe, Kenta; Usami, Yu; Pacifici, Maurizio; Iwamoto, Masahiro

    2016-09-01

    Heterotopic ossification (HO) consists of ectopic cartilage and bone formation following severe trauma or invasive surgeries, and a genetic form of it characterizes patients with Fibrodysplasia Ossificans Progressiva (FOP). Recent mouse studies showed that HO was significantly inhibited by systemic treatment with a corticosteroid or the retinoic acid receptor γ agonist Palovarotene. Because these drugs act differently, the data raised intriguing questions including whether the drugs affected HO via similar means, whether a combination therapy would be more effective or whether the drugs may hamper each other's action. To tackle these questions, we used an effective HO mouse model involving subcutaneous implantation of Matrigel plus rhBMP2, and compared the effectiveness of prednisone, dexamathaosone, Palovarotene or combination of. Each corticosteroid and Palovarotene reduced bone formation at max doses, and a combination therapy elicited similar outcomes without obvious interference. While Palovarotene had effectively prevented the initial cartilaginous phase of HO, the steroids appeared to act more on the bony phase. In reporter assays, dexamethasone and Palovarotene induced transcriptional activity of their respective GRE or RARE constructs and did not interfere with each other's pathway. Interestingly, both drugs inhibited the activity of a reporter construct for the inflammatory mediator NF-κB, particularly in combination. In good agreement, immunohistochemical analyses showed that both drugs markedly reduced the number of mast cells and macrophages near and within the ectopic Matrigel mass and reduced also the number of progenitor cells. In sum, corticosteroids and Palovarotene appear to block HO via common and distinct mechanisms. Most importantly, they directly or indirectly inhibit the recruitment of immune and inflammatory cells present at the affected site, thus alleviating the effects of key HO instigators. PMID:26891836

  11. RadioHPLC for pesticide ecotoxicity assay

    Czech Academy of Sciences Publication Activity Database

    Tykva, Richard; Vlasáková, Věra; Novák, Jaroslav

    Nice, 2003. s. 100. [Symposium on High Performance Liquid Phase Separations and Related Techniques /27./. 15.06.2003-19.06.2003, Nice] R&D Projects: GA ČR GA203/02/0247; GA ČR GA203/99/1447 Institutional research plan: CEZ:AV0Z5038910; CEZ:AV0Z4055905 Keywords : RadioHPLC Subject RIV: CC - Organic Chemistry

  12. Retinoid quantification by HPLC/MS(n)

    Science.gov (United States)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  13. HPLC Determination of Taurine in Sports Drinks

    Science.gov (United States)

    Orth, Dale L.

    2001-06-01

    The amino acid taurine (2-aminoethanesulfonic acid) is present as a nutritional supplement in many sports drinks. An experiment, suitable for a junior-senior level instrumental analysis course, is described to measure the amount of taurine in these sports drinks. A pre-column derivatization with Sanger's reagent, 2,4-dinitrofluorobenzene, is followed by an HPLC separation utilizing a gradient elution, and detection at 360 nm.

  14. Extensive extraosseous localization of bone imaging agent in a patient with renal failure and rhabdomyolysis accompanied by combined hypercalcemia and hyperphosphatemia

    Energy Technology Data Exchange (ETDEWEB)

    Shih, W.J.; Flueck, J.; O' Connor, W.; Domstad, P.A.

    1989-03-01

    Four sequential Tc-99m pyrophosphate (PYP) imaging studies were performed in a 28-year-old man with high fever and exudate pharyngitis associated with renal failure. Radiotracer localization in the left ventricle (LV), lungs, kidneys, and skeletal muscles were seen in two, initial imaging studies. In the second and third imaging studies, area of increase in activity was seen in the left-sided bowel. In studies done two months later (in the third study), the radioactivity in the skeletal muscles was no longer seen. Studies obtained nine months (in the fourth study) after the first imaging showed less radiotracer localization in the LV, lungs, and kidneys as compared to that seen in the initial study. Myocardial necrosis and microcalcification were proved by LV biopsy. The exact mechanism of extraosseous bone-imaging agent localization is unknown. However, this phenomenon may be related to renal failure, rhabdomyolysis, hypercalcemia, hyperphosphatemia, or elevated parathyroid hormone. The Tc-99m PYP imaging study is useful and sensitive in the detection of extraosseous tissue calcification and monitoring of the disease process.

  15. Agents Play Mix-game

    CERN Document Server

    Gou, C

    2005-01-01

    In mix-game which is an extension of minority game, there are two groups of agents; group1 plays the majority game, but the group2 plays the minority game. This paper studies the change of the average winnings of agents and volatilities vs. the change of mixture of agents in mix-game model. It finds that the correlations between the average winnings of agents and the mean of local volatilities are different with different combinations of agent memory length when the proportion of agents in group 1 increases. This study result suggests that memory length of agents in group1 be smaller than that of agent in group2 when mix-game model is used to simulate the financial markets.

  16. An Investigation Into HPLC Data Quality Problems

    Science.gov (United States)

    Hooker, Stanford B.; VanHeukelem, Laurie

    2011-01-01

    This report summarizes the analyses and results produced by a five-member investigative team of Government, university, and industry experts, established by NASA HQ. The team examined data quality problems associated with high performance liquid chromatography (HPLC) analyses of pigment concentrations in seawater samples produced by the San Diego State University (SDSU) Center for Hydro-Optics and Remote Sensing (CHORS). This report shows CHORS did not validate the methods used before placing them into service to analyze field samples for NASA principal investigators (PIs), even though the HPLC literature contained easily accessible method validation procedures, and the importance of implementing them, more than a decade ago. In addition, there were so many sources of significant variance in the CHORS methodologies, that the HPLC system rarely operated within performance criteria capable of producing the requisite data quality. It is the recommendation of the investigative team to a) not correct the data, b) make all the data that was temporarily sequestered available for scientific use, and c) label the affected data with an appropriate warning, e.g., "These data are not validated and should not be used as the sole basis for a scientific result, conclusion, or hypothesis--independent corroborating evidence is required."

  17. Discovery of Novel Tricyclic Thiazepine Derivatives as Anti-Drug-Resistant Cancer Agents by Combining Diversity-Oriented Synthesis and Converging Screening Approach.

    Science.gov (United States)

    Xiang, Jinbao; Zhang, Zhuoqi; Mu, Yan; Xu, Xianxiu; Guo, Sigen; Liu, Yongjin; Russo, Daniel P; Zhu, Hao; Yan, Bing; Bai, Xu

    2016-05-01

    An efficient discovery strategy by combining diversity-oriented synthesis and converging cellular screening is described. By a three-round screening process, we identified novel tricyclic pyrido[2,3-b][1,4]benzothiazepines showing potent inhibitory activity against paclitaxel-resistant cell line H460TaxR (EC50 100 μM against normal human fibroblasts). The most active hits also exhibited drug-like properties suitable for further preclinical research. This redeployment of antidepressing compounds for anticancer applications provides promising future prospects for treating drug-resistant tumors with fewer side effects. PMID:27082930

  18. Radioactive scanning agents with hydroquinone stabilizer

    International Nuclear Information System (INIS)

    Stable compositions useful as technetium 99m-based scintigraphic agents comprise hydroquinone in combination with a pertechnetate reducing agent or dissolved in pertechnetate-99m (sup(99m)TcOsub(4)sup(-)) solution. The compositions are especially useful in combination with a phosphate or phosphonate material which carries the radionuclide to bone, thus providing a skeletal imaging agent

  19. Evaluation of Drug-Drug Interactions between Direct-Acting Anti-Hepatitis C Virus Combination Regimens and the HIV-1 Antiretroviral Agents Raltegravir, Tenofovir, Emtricitabine, Efavirenz, and Rilpivirine.

    Science.gov (United States)

    Khatri, Amit; Dutta, Sandeep; Dunbar, Martin; Podsadecki, Thomas; Trinh, Roger; Awni, Walid; Menon, Rajeev

    2016-05-01

    The three direct-acting antiviral agent (3D) regimen is a novel combination of direct-acting antiviral agents (DAAs) that has proven effective for the treatment of hepatitis C virus (HCV) infection. Given the potential for coadministration in patients with human immunodeficiency virus infection, possible drug interactions with antiretroviral drugs must be carefully considered. Four phase 1, multiple-dose pharmacokinetic studies were conducted in healthy volunteers (n = 66). The 3D regimen of 150/100 mg daily paritaprevir/ritonavir, 25 mg daily ombitasvir, and 400 mg twice-daily dasabuvir was administered alone or in combination with 200 mg daily of emtricitabine and 300 mg daily of tenofovir disoproxil fumarate (tenofovir DF), 25 mg daily of rilpivirine, or 400 mg of raltegravir twice daily. A 2-DAA regimen of 150/100 mg daily paritaprevir/ritonavir and 400 mg of dasabuvir twice daily was also studied in combination with efavirenz/emtricitabine/tenofovir DF at 600/200/300 mg daily, respectively (Atripla; Bristol-Myers Squibb). Pharmacokinetic parameters were determined from plasma drug concentrations. No clinically significant drug interactions were observed (≤32% change in exposure) between the 3D regimen and that of emtricitabine plus tenofovir DF. Raltegravir exposure was increased up to 134% when the drug was coadministered with the 3D regimen. Although coadministration with rilpivirine was well tolerated in healthy volunteers, observed elevations in rilpivirine exposures may increase the potential for adverse drug reactions. Concomitant use of the 2-DAA regimen and efavirenz/emtricitabine/tenofovir DF was discontinued owing to poor tolerability and adverse events. No dose adjustment is required during coadministration of raltegravir, tenofovir DF, or emtricitabine with the 3D regimen. Rilpivirine is not recommended and efavirenz is contraindicated for coadministration with the 3D regimen. PMID:26953200

  20. Comparative evaluation of dexmedetomidine and midazolam-ketamine combination as sedative agents in pediatric dentistry: A double-blinded randomized controlled trial

    Science.gov (United States)

    Malhotra, Parul Uppal; Thakur, Seema; Singhal, Parul; Chauhan, Deepak; Jayam, Cheranjeevi; Sood, Ritu; Malhotra, Yagyeshwar

    2016-01-01

    Background: Pharmacological methods have been used as an adjunct to enhance child cooperativeness and facilitate dental treatment. Objective: Purpose of this study was to evaluate and compare the effect of sedation by intranasal dexmedetomidine and oral combination drug midazolam–ketamine in a group of children with uncooperative behavior requiring dental treatment. Materials and Methods: This was a prospective, randomized, double-blind study that included patients 3–9 years old with American Society of Anesthesiologists-I status. About 36 children presenting early childhood caries were randomly assigned to one of three groups studied: Group MK received intranasal saline and oral midazolam (0.5 mg/kg) with ketamine (5 mg/kg) mixed in mango juice; Group DX received intranasal dexmedetomidine (1 μg/kg) and oral mango juice; and Group C received intranasal saline and oral mango juice. Patients' heart rate, blood pressure, and oxygen saturation were recorded before, during, and at the end of the procedure. Patients' behavior, sedation status, and wake up behavior were evaluated with modified observer assessment of alertness and sedation scale. Ease of treatment completion was evaluated according to Houpt scale. Results: Hemodynamic changes were statistically insignificant in Group MK and Group DX. About 75% patients in Group MK were successfully sedated as compared to 53.9% Group DX and none of the patients in Group C. Ease of treatment completion was better with Group MK as compared to Group DX and least with Group C. Around 50% patients in Group MK had postoperative complications. Conclusion: Oral midazolam–ketamine combination and intranasal dexmedetomidine evaluated in the present study can be used safely and effectively in uncooperative pediatric dental patients for producing conscious sedation. PMID:27307665

  1. HPLC METHOD DEVELOPMENT OF AMLODIPINE BY RP-HPLC IN ITS BULK DOSAGE FORMS

    OpenAIRE

    V. Naveen Kumar, K. Kiran kumar, P. Ramesh Babu, K. Anilkumar

    2012-01-01

    A new, simple, precise, sensitive, accurate and reproducible Reverse phase HPLC method was developed and validated for the analysis of amlodipine in bulk dosage forms. The separation was conducted by using c-18 RP-HPLC coloumn, which was maintained at ambient temperature. The mobile phase consisting of Phosphate buffer and Acetonitrile (90:10v/v) was delivered at a rate of 1.5 ml/min. The analysis was detected by using UV detector at the wave length of 225nm.The method is validated for its ...

  2. Weight and Glucose Reduction Observed with a Combination of Nutritional Agents in Rodent Models Does Not Translate to Humans in a Randomized Clinical Trial with Healthy Volunteers and Subjects with Type 2 Diabetes.

    Directory of Open Access Journals (Sweden)

    Rebecca J Hodge

    Full Text Available Nutritional agents have modest efficacy in reducing weight and blood glucose in animal models and humans, but combinations are less well characterized. GSK2890457 (GSK457 is a combination of 4 nutritional agents, discovered by the systematic assessment of 16 potential components using the diet-induced obese mouse model, which was subsequently evaluated in a human study.In the diet-induced obese mouse model, GSK457 (15% w/w in chow given with a long-acting glucagon-like peptide -1 receptor agonist, exendin-4 AlbudAb, produced weight loss of 30.8% after 28 days of treatment. In db/db mice, a model of diabetes, GSK457 (10% w/w combined with the exendin-4 AlbudAb reduced glucose by 217 mg/dL and HbA1c by 1.2% after 14 days.GSK457 was evaluated in a 6 week randomized, placebo-controlled study that enrolled healthy subjects and subjects with type 2 diabetes to investigate changes in weight and glucose. In healthy subjects, GSK457 well tolerated when titrated up to 40 g/day, and it reduced systemic exposure of metformin by ~ 30%. In subjects with diabetes taking liraglutide 1.8 mg/day, GSK457 did not reduce weight, but it slightly decreased mean glucose by 0.356 mmol/L (95% CI: -1.409, 0.698 and HbAlc by 0.065% (95% CI: -0.495, 0.365, compared to placebo. In subjects with diabetes taking metformin, weight increased in the GSK457-treated group [adjusted mean % increase from baseline: 1.26% (95% CI: -0.24, 2.75], and mean glucose and HbA1c were decreased slightly compared to placebo [adjusted mean glucose change from baseline: -1.22 mmol/L (95% CI: -2.45, 0.01; adjusted mean HbA1c change from baseline: -0.219% (95% CI: -0.910, 0.472].Our data demonstrate remarkable effects of GSK457 in rodent models of obesity and diabetes, but a marked lack of translation to humans. Caution should be exercised with nutritional agents when predicting human efficacy from rodent models of obesity and diabetes.ClinicalTrials.gov NCT01725126.

  3. Investigation of mechanism of bone regeneration in a porous biodegradable calcium phosphate (CaP) scaffold by a combination of a multi-scale agent-based model and experimental optimization/validation

    Science.gov (United States)

    Zhang, Le; Qiao, Minna; Gao, Hongjie; Hu, Bin; Tan, Hua; Zhou, Xiaobo; Li, Chang Ming

    2016-08-01

    Herein, we have developed a novel approach to investigate the mechanism of bone regeneration in a porous biodegradable calcium phosphate (CaP) scaffold by a combination of a multi-scale agent-based model, experimental optimization of key parameters and experimental data validation of the predictive power of the model. The advantages of this study are that the impact of mechanical stimulation on bone regeneration in a porous biodegradable CaP scaffold is considered, experimental design is used to investigate the optimal combination of growth factors loaded on the porous biodegradable CaP scaffold to promote bone regeneration and the training, testing and analysis of the model are carried out by using experimental data, a data-mining algorithm and related sensitivity analysis. The results reveal that mechanical stimulation has a great impact on bone regeneration in a porous biodegradable CaP scaffold and the optimal combination of growth factors that are encapsulated in nanospheres and loaded into porous biodegradable CaP scaffolds layer-by-layer can effectively promote bone regeneration. Furthermore, the model is robust and able to predict the development of bone regeneration under specified conditions.

  4. Determination of racecadotril by HPLC in capsules

    OpenAIRE

    Prabu S; Singh T; Joseph A; Kumar C; Shirwaikar A

    2007-01-01

    A simple, precise and rapid RP-HPLC method was developed for the determination of racecadotril in a pharmaceutical formulation using gemfibrozil as internal standard. Ratio of the peak area of analyte to internal standard was used for quantification. The chromatographic separation was carried out by using a Reverse Phase C18 column (BDS-Hypersil). The mobile phase consisting of a mixture of 20 mM phosphate buffer (pH 3.5) and acetonitrile in the ratio of (40:60) with detection at 230 nm at a ...

  5. Solution-based colloidal synthesis of hybrid P3HT: Ternary CuInSe2 nanocomposites using a novel combination of capping agents for low-cost photovoltaics

    Science.gov (United States)

    Sharma, Shailesh Narain; Chawla, Parul; Akanksha; Srivastava, A. K.

    2016-06-01

    In this work, ternary CuInSe2 (CISe) chalcopyrite nanocrystallites efficiently passivated by a novel combination of capping agents viz: aniline and 1-octadecene during chemical route synthesis were dispersed in conducting polymer matrix poly(3-hexylthiophene) (P3HT). By varying the composition and concentration of the ligands, the properties of the resulting CISe nanocrystallites and its corresponding polymer nanocomposites thus could be tailored. The structural, morphological and optical studies accomplished by various complimentary techniques viz. Transmission Electron Microscopy (TEM), Contact angle, Photoluminescence (PL) and Raman have enabled us to compare the different hybrid organic (polymer)-inorganic nanocomposites. On the basis of aniline-octadecene equilibrium phase diagram, the polydispersity of the CISe nanocrystals could be tuned by using controlled variations in the reaction conditions of nucleation and growth such as composition of the solvent and temperature. To the best of author's knowledge, the beneficial effects of both the capping agents; aniline and octadecene contributing well in tandem in the development of large-sized (100-125 nm) high quality, sterically- and photo-oxidative stable polycrystalline CISe and its corresponding polymer (P3HT):CISe composites with enhanced charge transfer efficiency has been reported for the first time. The low-cost synthesis and ease of preparation renders this method of great potential for its possible application in low-cost hybrid organic-inorganic photovoltaics. The figure shows the Temperature vs Mole fraction graph of two different phases (aniline and 1-octadecene) in equilibrium.

  6. HPLC-MS technique for radiopharmaceuticals research and control

    International Nuclear Information System (INIS)

    A liquid chromatography/refractive index detector/radiometric detector/ mass spectrometric detector combination (Agilent 1100 HPLC/RAD/DAD/RID/MSD system) is used as a complex technique for quality assessment of radiopharmaceuticals such as 2-deoxy-2-[18F]fluoro-D-glucose (FDG). Optimisation of HPLC/MS analysis was performed investigating the electrospray ionisation (ESI) analytical signal of the mass spectrometer as a function of solvent composition. The anion-exchange eluents applied as specified by the pharmacopoeia are not suitable for ESI detection due to high ion concentrations. Therefore, solutions of glucose in methanol/water and acetonitrile/water solutions of various semi-volatile electrolytes (ammonium chloride, formic acid, ammonium formate) were analysed by flow injection analysis (FIA) and chromatographically. The best analytical response was obtained with acetonitrile : 0.25% ammonium formate = 80:20 solutions. The most intense MSD signals of FDG in ammonium formate were obtained for the following complex ions: (i) positive ions: fdg.NH4+, fdg.Na+ and (fdg2-CH3O).Na+ (m/z = 200, 205 and 344); (ii) negative ions: fdg.Cl- and fdg.HCOO- (m/z= 217 and 227). The HPLC-MS analysis with Zorbax C-18 and Asahipak-NH2P50 columns gave evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloro-glucose, erythrose, erythritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[19F]FDG, sorbitol/[19F]FDG, xylitol, and other compounds. However, radiometric analysis of expired samples of [18F]FDG gave evidence of a very high radiation stability of its water-ethanol solutions at the point of output of radioactive products. Remarkable is the exceedingly high complexity of the mass spectra of FDG as compared to glucose. Therefore, further research concerns the influence of sodium chloride, linearity of signal response, impurities (mannitol, mannose etc.) interference, and robustness of the MS analysis, with special attention to the ratio of

  7. HPLC-NMR revisited: Using time-slice HPLC-SPE-NMR with database assisted dereplication

    DEFF Research Database (Denmark)

    Johansen, Kenneth; Wubshet, Sileshi Gizachew; Nyberg, Nils

    2013-01-01

    Time based trapping of chromatographically separated compounds on to solid-phase extraction cartridges (SPE) and subsequent elution to NMR-tubes was done to emulate the function of HPLC–NMR for dereplication purposes. Sufficient mass sensitivity was obtained by the use of a state-of-the-art HPLC...

  8. An improved HPLC method for determination of colocynthin in colocynth

    Directory of Open Access Journals (Sweden)

    M. Shekarchi

    2015-10-01

    Full Text Available Background and objectives: Colocynthin is the major active secondary metabolite of colocynth, Citrullus colocynthis (L. Schrad, which has been used in traditional and ethno medicine of many countries.  It could be considered as an active marker for quality control of colocynth and its herbal products. Analysis and standardization of colocynth and its herbal preparations are a critical issue for their safe applications in phytotherapy and traditional medicine. In the present work, a simple and efficient sample preparation was developed and optimized through combination of matrix solid phase dispersion and ultrasonic assisted extraction. In addition, analytical reversed-phase HPLC method was optimized for analyzing the concentration of colocynthin in colocynth pulp. Methods: Powdered colocynth pulp was grinded with diatomaceous earth to obtain a homogenous mixture. The blend was mixed with methanol and extracted by sonication, followed by centrifugation and filtration. The analytical chromatographic separation was carried out using Luna C18 in isocratic elution with methanol: isopropanol: water: triflouroacetic acid (30:10:60:0.1 v/v. The method was validated as well.  Results: The validation parameters were determines as follows, linear range (r2 = 0.999, 75-500 μg/mL, precision (intra-day < 2.7%, inter-day = 4.4% and accuracy measured via determination of recovery (90-107%. The limit of detection and quantization were calculated 8.5 and 25.7 μg/mL, respectively. Conclusion: Regarding the relatively high content of colocynthin in colocynth pulp, the validated HPLC method could be applied for quality control of colocynth pulp used in Traditional Persian Medicine.

  9. 碱性清洗剂联合超声清洗机在妇科器械清洗中的应用%Application of alkaline cleaning agent combined with ultrasonic cleaning machine in cleaning equipment in gynecology

    Institute of Scientific and Technical Information of China (English)

    冉茂勤

    2015-01-01

    Objective:To explore the effect of alkaline cleaning agent combined with ultrasonic cleaning machine in cleaning equipment in gynecology.Methods:300 suction head and vaginal speculum were selected.They were randomly divided into A group,B group,C group.A group was given the medical soft brush washing and rinsing with water cannons,and then they were putted into the automatic cleaning machine.B group was soaked for 10 minutes with pH neutral potent multi enzyme cleaning agent,and then washed with A method.C group was shaked for 10 minutes in the ultrasonic vibration machine with alkaline cleaning agent,and then washed with A method.We compared the cleaning effect.Results:After cleaning,the qualified rate of A group was 58%;the qualified rate of B group was 90%;the qualified rate of C group was 100%.Conclusion:Cleaning effect was the best of ultrasound machine vibration plus alkaline cleaning agent plus high-pressure water washing brush.%目的:探讨碱性清洗剂联合超声清洗机清洗妇科复用器械的效果。方法:选择吸引头、窥阴器共300个,随机分成A、B、C 3个组,A组用医用软毛刷刷洗后用高压水枪冲洗,然后放入全自动清洗机清洗;B组用pH值中性的强效多酶清洗剂浸泡10 min后再用A组方法清洗;C组放入已加碱性清洗剂的超声机震动10 min再用A组方法清洗,比较清洗效果。结果:清洗后,A组合格率58%,B组合格率90%,C组合格率100%。结论:采用超声机震动+碱性清洗剂+毛刷+高压水枪冲洗,其清洗消毒效果最佳。

  10. Comparison of Two Species of Notopterygium by GC-MS and HPLC

    OpenAIRE

    Yaping Wang; Linfang Huang

    2015-01-01

    Notopterygii Rhizoma et Radix (Qianghuo), including Notopterygium incisum Ting ex H. T. Chang (NI) and Notopterygium franchetii H. de Boiss (NF), is an important traditional Chinese medicine. Of these two plants, NI, is more commonly used and has a much higher price in the marketplace. To compare these two plants, a combination of gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC) was carried out, thus obtaining an overall characterization for both ...

  11. Agent Assignment for Process Management: Pattern Based Agent Performance Evaluation

    Science.gov (United States)

    Jablonski, Stefan; Talib, Ramzan

    In almost all workflow management system the role concept is determined once at the introduction of workflow application and is not reevaluated to observe how successfully certain processes are performed by the authorized agents. This paper describes an approach which evaluates how agents are working successfully and feed this information back for future agent assignment to achieve maximum business benefit for the enterprise. The approach is called Pattern based Agent Performance Evaluation (PAPE) and is based on machine learning technique combined with post processing technique. We report on the result of our experiments and discuss issues and improvement of our approach.

  12. Determination of CMPO using HPLC-UV.

    Science.gov (United States)

    Elias, Gracy; Groenewold, Gary S; Mincher, Bruce J; Mezyk, Stephen P

    2012-06-22

    Octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) is an extractant proposed for selective separation of radionuclide metals from used nuclear fuel solutions using solvent extraction. Radiolysis reactions can degrade CMPO and reduce separation performance and hence methods for measuring the concentration of CMPO are needed. A novel high performance liquid chromatography (HPLC) method was developed for measuring CMPO in dodecane that featured a low pH buffer, octanol as a co-solvent with 2-propanol, and ultraviolet (UV) detection. Validation data indicated that the HPLC-UV method for CMPO determination provided good linearity, sensitivity, accuracy and precision. Method performance was evaluated using CMPO samples that had undergone radiolysis, and the results showed a decrease in CMPO concentration and the appearance of degradation products. The degradation products were identified using electrospray ionization mass spectrometry, which also showed formation of CMPO-nitric acid complexes that account for the apparent loss of CMPO in an acidic environment, independent of irradiation. PMID:22595518

  13. Preliminary study of the transcatheter arterial chemoembolization in combination of percutaneous injection of chemoembolization agent intra-portal vein tumor thrombosis in treatment of primary hepatic carcinoma accompanied by portal vein tumor thrombosis

    International Nuclear Information System (INIS)

    Objective: To assess the therapeutic outcomes of transcatheter arterial chemoembolization combined with percutaneous injection of chemoembolization agent intra-portal vein tumor thrombosis for primary hepatic carcinoma accompanied by portal vein tumor thrombus. Methods: Thirty patients with primary hepatic carcinoma accompanied by portal vein tumor thrombosis of type II and type III were randomly divided into two groups. The Child-Pugh ratings (class A and B) of group A and B were 9 vs 9 (class A) and 5 vs 7 (class B) respectively (χ2=0.201, P>0.05). The constitution of Type II and type III portal vein tumor thrombus in group A and B were 8 vs 9 and 6 vs 7 respectively (χ2= 0.002, P>0.05). The median values of ALT, TBIL, ALB and AFP in group A and B were 58.7U/L vs 70.5 U/L (W=191.5, P>0.05), 21.4 μmol/L vs 21.7 μmol/L (W=203, P>0.05), 35.3 g/L vs 37.5 g/L (W=214,P>0.05) and 680 μg/L vs 873 μg/L (W=179.00, P>0.05) respectively. Group A was treated with transcatheter arterial chemoembolization (TACE) using emulsion made up of adriamycin, cisplatin, mitomycin and ultraliquidlipiodol plus percutaneous injection of chemoembolization agent intra- portal vein tumor thrombosis using emulsion consisted of cisplatin and ultraliquidlipiodol, while group B was treated with TACE only as a control group. Survival analyses were performed via the Kaplan-Meier test in SPSS11.5 with the log-rank tests with an threshold of 0.05. Results: The 3, 6 and 12 months survival cases of group A and B were 11 vs 10, 10 vs 3, and 7 vs 0 respectively. The median survival time of group A and group B were 14.0 months and 4.0 months respectively. The difference of the two groups was significantly (χ2=11.728, P<0.01). There was no severe side-effect related to therapy in both groups. Conclusion: Comparing with the control group, TACE combined with percutaneous injection of chemoembolization agent intra-portal vein tumor thrombosis could significantly prolong the median survival time of

  14. Agent, autonomous

    OpenAIRE

    Luciani, Annie

    2007-01-01

    The expression autonomous agents, widely used in virtual reality, computer graphics, artificial intelligence and artificial life, corresponds to the simulation of autonomous creatures, virtual (i.e. totally computed by a program), or embodied in a physical envelope, as done in autonomous robots.

  15. Quantitative determination of a-Arbutin, ß-Arbutin, Kojic acid, nicotinamide, hydroquinone, resorcinol, 4-methoxyphenol, 4-ethoxyphenol and ascorbic acid from skin whitening Products by HPLC-UV

    Science.gov (United States)

    Development of an analytical method for the simultaneous determination of multifarious skin whitening agents will provide an efficient tool to analyze skin whitening cosmetics. An HPLC-UV method was developed for quantitative analysis of six commonly used whitening agents, a-arbutin, ß-arbutin, koji...

  16. Identification, synthesis and characterization of process related desfluoro impurity of ezetimibe and HPLC method validations

    Institute of Scientific and Technical Information of China (English)

    Esen Bellur Atici; Bekir Karlığa

    2015-01-01

    Ezetimibe, which selectively inhibits cholesterol absorption across the intestinal wall and is used as an antihyperlipidemic agent, is synthesized for commercial use as a drug substance in highly pure form. During the synthetic process development studies of ezetimibe, an impurity was detected in the final product at levels ranging from 0.05% to 0.15% in reverse phase gradient high performance liquid chro-matography (HPLC) method and its molecular weight was determined by LC–MS analysis. The impurity was identified as (3R,4S)-3-((S)-3-(4-fluorophenyl)-3-hydroxypropyl)-4-(4-hydroxyphenyl)-1-phenyla-zetidin-2-one which is called desfluoro ezetimibe (lactam-related) impurity, synthesized and char-acterized, the mechanism of its formation was discussed in detail. After all standardization procedures, it was used as a reference standard during validation of HPLC method and routine analyses. In addition, content of Eze-1 desfluoro impurity in Eze-1 intermediates was specified as 0.10%to keep the formation of desfluoro ezetimibe impurity under control and the related substances HPLC method was validated accordingly.

  17. Qualitative analysis of MDR-reversing Anastasia Black (Russian black sweet pepper, Capsicum annuum, Solanaceae) extracts and fractions by HPLC and LC-MS-MS methods

    OpenAIRE

    Schelz, Zsuzsanna; Molnar, Joseph; Fogliano, Vincenzo; Ferracane, Rosalia; Pernice, Rita; 白瀧, 義明; 本橋, 登

    2006-01-01

    In earlier experiments, the MDR (multidrug resistance)-reversal activities of Anastasia Black (Russian black sweet pepper) extracts had been analysed. Recently, the most effective MDR reversing extracts and fractions have been separated by HPLC (high-performance liquid chromatography, for carotenoids) and LC-MS-MS (HPLC combined with mass spectrometry, for phenolic compounds) methods. As a result of the analytical studies, the following flavonoids had been identified: feruloyl glucopyranoside...

  18. Agent-Based Health Monitoring System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose combination of software intelligent agents to achieve decentralized reasoning, with fault detection and diagnosis using PCA, neural nets, and maximum...

  19. Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator

    Science.gov (United States)

    Shalliker, R. A.; Kayillo, S.; Dennis, G. R.

    2008-01-01

    Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

  20. Off-line 2D HPLC of aliphatic hydrocarbons

    Czech Academy of Sciences Publication Activity Database

    Vrkoslav, Vladimír; Vít, M.; Cvačka, Josef

    Geneva : -, 2014. s. 260. [IMSC 2014. International Mass Spectrometry Conference /20./. 24.08.2014-29.08.2014, Geneva] R&D Projects: GA ČR GAP206/12/1093 Institutional support: RVO:61388963 Keywords : RP-HPLC * Ag-HPLC * long chain hydrocarbons Subject RIV: CB - Analytical Chemistry, Separation

  1. [Analysis of porphyrin photosensitizers using HPLC method].

    Science.gov (United States)

    Jia, Min-ge; Wu, Hai-yan; Sun, Li-li; Yao, Chun-suo; Zhang, Shao-liang; Li, Ya-wei; Fang, Qi-cheng

    2015-08-01

    Photodynamic therapy (PDT), because of its good targeting, minimal invasion, and safety, is becoming a very active area in cancer prevention and treatment, in which the photosensitizers have proved to be the core element for PDT. We developed a new HPLC method for analyzing porphyrin photosensitizers using Shiseido Capcell PAK C18 (150 mm x 4.6 mm, 5 µm) as the column at 30 °C, methanol-1% aqueous solution of acetic acid as the mobile phase in a flow rate of 1.0 mL · min(-1) in a gradient elution mode, and the detection wavelength at 380 nm. This method, showing good specificity, precision, accuracy and robusty via methodology validations, can be applied to the purity test and assay of porphyrin photosensitizers, and has played a key guide role in the R&D of the new porphyrin photosensitizer--sinoporphyrin sodium. PMID:26669003

  2. Characterization of zirconized silica supports for HPLC

    International Nuclear Information System (INIS)

    The preparation and characterization of zirconized silica has been investigated. The material was prepared via the reaction of silica with zirconium tetrabutoxide, optimized by a central composite design and response surface methodology. The new material was characterized by nitrogen adsorption-desorption investigations (BET/BJH) showing specific surface areas adequate for use as a chromatographic support. DRUVS, FTIR, XPS, XAS, XRF and SEM methods also were used to characterize the new material. It was shown that silica networks were not significantly modified with the introduction of zirconium. Surface analyses show that there is appreciable element enrichment at the surface, while significant changes in binding energies of Zr 3d, Si 2p, and O 1s have been detected. The above observations indicate that Si-O-Zr bonds were formed, with zirconium grafted onto the silica surface, yielding a support suitable for HPLC

  3. Determination of racecadotril by HPLC in capsules

    Directory of Open Access Journals (Sweden)

    Prabu S

    2007-01-01

    Full Text Available A simple, precise and rapid RP-HPLC method was developed for the determination of racecadotril in a pharmaceutical formulation using gemfibrozil as internal standard. Ratio of the peak area of analyte to internal standard was used for quantification. The chromatographic separation was carried out by using a Reverse Phase C18 column (BDS-Hypersil. The mobile phase consisting of a mixture of 20 mM phosphate buffer (pH 3.5 and acetonitrile in the ratio of (40:60 with detection at 230 nm at a flow rate of 1 ml/min was employed. The method was statistically validated for linearity, accuracy and precision. The elution time was 6.9 min for racecadotril and 9.8 min for gemfibrozil. The simplicity and accuracy of the proposed method ensures its use in routine quality control analysis of pharmaceutical formulations.

  4. [Antipsychotic agents and stimulants: a judicious combination?].

    Science.gov (United States)

    de Jong, M H; Eussen, M L J M; van Gool, A R

    2010-01-01

    A 31-year-old male, diagnosed with schizophrenia and receiving maintenance treatment with olanzapine, was prescribed methylphenidate for comorbid attention deficit hyperactivity disorder (adhd). The adhd symptoms diminished and there were hardly any side-effects. No increase in psychotic symptoms occurred. The patient used far fewer amphetamines and benzodiazepines. In theory, stimulants and antipsychotics produce opposite effects. Relevant literature on the subject is discussed. PMID:20054798

  5. Development and validation of an HPLC-MS/MS analytical method for quantitative analysis of TCBA-TPQ, a novel anticancer makaluvamine analog, and application in a pharmacokinetic study in rats

    OpenAIRE

    Jun-Xian, YU; Voruganti, Sukesh; Dan-Dan, LI; Qin, Jiang-Jiang; Nag, Subhasree; Xu, Su; Velu, Sadanandan E.; Wang, Wei; Zhang, Ruiwen

    2015-01-01

    We have recently designed and synthesized several novel iminoquinone anticancer agents that have entered preclinical development for the treatment of human cancers. Herein we developed and validated a quantitative HPLC-MS/MS analytical method for one of the lead novel anticancer makaluvamine analog, TCBA-TPQ, and conducted a pharmacokinetic study in laboratory rats. Our results indicated that the HPLC-MS/MS method was precise, accurate, and specific. Using this method, we carried out in vitro...

  6. HPLC METHOD DEVELOPMENT OF AMLODIPINE BY RP-HPLC IN ITS BULK DOSAGE FORMS

    Directory of Open Access Journals (Sweden)

    V. Naveen Kumar, K. Kiran kumar, P. Ramesh Babu, K. Anilkumar

    2012-06-01

    Full Text Available A new, simple, precise, sensitive, accurate and reproducible Reverse phase HPLC method was developed and validated for the analysis of amlodipine in bulk dosage forms. The separation was conducted by using c-18 RP-HPLC coloumn, which was maintained at ambient temperature. The mobile phase consisting of Phosphate buffer and Acetonitrile (90:10v/v was delivered at a rate of 1.5 ml/min. The analysis was detected by using UV detector at the wave length of 225nm.The method is validated for its specificity, precision, accuracy, linearity and robustness. The method was found to be linear over the concentration range 10-100 g/ml (r2 =0.999. The retention time for amlodipine was found to be 3.34min. Limit of quantification of the method is 0.179g/ml and limit of detection is 0.054 g/ml.

  7. HPLC and HPLC/MS analysis of red ink on counterfeit 100-yuan notes.

    Science.gov (United States)

    Xu, Ying-jian; Zhou, Xin-xin; Shi, Xiao-fan

    2016-02-01

    Counterfeiting is a significant problem for most major currencies and has high social and economic costs. Chemical and physical identifiers that are unique to counterfeit currency are critical to forensic analysis. The 100-yuan Chinese note is mostly red. Here, we analyzed the red ink used in 100-yuan Chinese notes and developed a method to extract and analyze these dyes via high performance liquid chromatography (HPLC) and HPLC/mass spectrometry (MS). We used this approach to analyze the chemical structures of the adulterated colorants from 46 counterfeit 100-yuan notes seized from different locations. The results showed that a variety of inks were found among the seized counterfeit notes from different sources. The chromatographic data signature could be used to clearly discriminate authentic from counterfeit notes, but could also potentially be used to trace the notes to the counterfeiter. To the best of our knowledge, this is the first report to use HPLC/MS to profile red dyes in Chinese currency with important implications for the forensics and law enforcement communities. PMID:26750988

  8. Testing of radiopharmaceuticals by HPLC: continuation and end; Control des radiopharmaceutiques par HPLC: suite et fin

    Energy Technology Data Exchange (ETDEWEB)

    Prangere, T.; Fialdes, P.; Douja, N.; Marchandise, X.; Steiling, M. [Unite de Radiopharmacie, Institut de Medecine Nucleaire, CHRU Lille, 59037 Lille Cedex (France)

    1997-12-31

    We presented last year a new testing technique of radiochemical purity by HPLC applicable in numerous radiopharmaceuticals. But, it was not efficient for usual tracers such as the HMDP or DTPA. We have developed a new method for these molecules. As materials we made use of: - the HPLC Waters system equipped with the code Millenium; - the U.V.Waters 486 detector set to 300 nm; - the Flow count-Bioscan (Wallac) radioactivity detector; - the column Waters Nova-pak, C18 60A 4{mu}m, 3.9 x 150 mm. Concerning the method, we made use of gradient separation method as follows: for 0{yields}3 min: 100% butanol-1, 0.7 ml/min; for 3{yields} 17 min: passage by 100% water by linear gradient; and for 7 {yields} 15 min: gradual flow-rate augmentation to 2 ml/min. We obtained for the retention time (RT) of pertechnetate the value 2 min. This method allows separating the HMDP, the Phytate, the DTPA and the DMSA which present an identical RT of 10.5 min. The hydrolyzed and reduced Tc was not made evident. In conclusion, due to its facility, rapidity and low cost this methodology may be used on a routine base to test the radiochemical purity of these four tracers in a service equipped by a HPLC

  9. HPLC and HPLC-MS as tools to monitor the quality of vegetable oils, nutraceuticals, and functional foods

    Science.gov (United States)

    HPLC and HPLC-MS have become valuable tools to analyze the “functional lipids” in vegetable oils, nutraceuticals, functional foods, and conventional foods. These functional lipids include phytosterols, tocopherols, tocotrienols, and carotenoids. These analytical methods have provided a means to id...

  10. Comparison of Two Species of Notopterygium by GC-MS and HPLC

    Directory of Open Access Journals (Sweden)

    Yaping Wang

    2015-03-01

    Full Text Available Notopterygii Rhizoma et Radix (Qianghuo, including Notopterygium incisum Ting ex H. T. Chang (NI and Notopterygium franchetii H. de Boiss (NF, is an important traditional Chinese medicine. Of these two plants, NI, is more commonly used and has a much higher price in the marketplace. To compare these two plants, a combination of gas chromatography-mass spectrometry (GC-MS and high performance liquid chromatography (HPLC was carried out, thus obtaining an overall characterization for both volatile and none-volatile compounds. Combined with hierarchical cluster analysis (HCA and principal component analysis, GC-MS was successfully applied to distinguish NF and NI. The chemical constitutes of volatile oil in NI and NF were firstly compared in detail, and 1R-alpha-pinene, beta-pinene and 4-isopropyl-1-methyl-1,4-cyclohexadiene had great contribution to the discrimination. Fingerprints of 14 batches of Qinghuo samples were also established based on HPLC, and an obvious difference was found between the two species. The chromatographic fingerprints were further analyzed by similarity analysis and HCA. The present study is the first reported evaluation of two origins of Notopterygii Rhizoma et Radix by GC-MS and HPLC, which will facilitate quality control and its clinical application.

  11. Identification of a Panax ginseng fruit fingerprint by HPLC-ESI-MS.

    Science.gov (United States)

    Zhao, H F; Xu, F F; Guo, Y T; Mi, H

    2016-01-01

    Over many years, parts of Panax ginseng (root and rhizome) have been identified and applied for medical purposes as traditional Chinese herbal medicine. Recently, research has indicated that ginseng fruit also contains similar compounds and is as rich as the other parts of the ginseng. This discovery may dramatically improve the efficient of outputs derived from ginseng products. Here, a new technique combining high-performance liquid chromatography (HPLC) with electrospray ionization tandem mass spectrometry (ESI-MS) was employed to identify the fingerprint of P. ginseng fruit. Using HPLC, compounds that are important for medical purposes were extracted and purified. Combined with ESI-MS, the characteristic peaks (nine common peaks) of those compounds were identified, and the accuracy was confirmed by analysis using the Chromatographic Fingerprint Similarity Evaluation System (2004A edition). Overall, 15 batches of ginseng fruit had a similarity of more than 0.80, 13 batches of samples had a similarity between 0.97 and 0.99, and two batches had a similarity less than 0.90. The test solution and mobile phase selection was discussed. The HPLC-ESI-MS method can produce repeatable and reliable results and can be applied in the quality control of P. ginseng fruit. PMID:26985953

  12. Participatory Simulation of Land-Use Changes in the Northern Mountains of Vietnam: the Combined Use of an Agent-Based Model, a Role-Playing Game, and a Geographic Information System

    Directory of Open Access Journals (Sweden)

    Tran Ngoc Trung

    2005-06-01

    Full Text Available In Vietnam, the remarkable economic growth that resulted from the doi moi (renovation reforms was based largely on the rural households that had become the new basic unit of agricultural production in the early 1990s. The technical, economic, and social changes that accompanied the decollectivization process transformed agricultural production, resource management, land use, and the institutions that defined access to resources and their distribution. Combined with the extreme biophysical, technical, and social heterogeneity encountered in the northern mountains, these rapid changes led to the extreme complexity of the agrarian dynamics that today challenges traditional diagnostic approaches. Since 1999, a participatory simulation method has been developed to disentangle the cause-and-effect relationships between the different driving forces and changes in land use observed at different scales. Several tools were combined to understand the interactions between human and natural systems, including a narrative conceptual model, an agent-based spatial computational model (ABM, a role-playing game, and a multiscale geographic information system (GIS. We synthesized into an ABM named SAMBA-GIS the knowledge generated from the above tools applied to a representative sample of research sites. The model takes explicitly into account the dynamic interactions among: (1 farmers' strategies, i.e., the individual decision-making process as a function of the farm's resource profile; (2 the institutions that define resource access and usage; and (3 changes in the biophysical and socioeconomic environment. The next step consisted of coupling the ABM with the GIS to extrapolate the application of local management rules to a whole landscape. Simulations are initialized using the layers of the GIS, e.g., land use in 1990, accessibility, soil characteristics, etc., and statistics available at the village level, e.g., population, ethnicity, livestock, etc. At each

  13. Analysis of Phospholipids in Crucian Carp(Carassius auratus) Muscle by Offline HPLC-MALDI-TOF MS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The interest in the analysis of phospholipids(PLs), especially phosphatidylcholine(PC), has been increasing due to the importance of them in biochemistry as well as in industry. A method was reported based on the offline combination of MALDI-TOF MS and normal-phase HPLC for analyzing PLs extracted from crucian carp. Total PLs of crucian carp were extracted and then separated by HPLC before the collected subfractions were analyzed by MALDI-TOF MS. The mass spectra obtained show peaks of H+, Na+ and K+ adducts of PC molecules. It is shown that the prior separation of PLs by HPLC is highly necessary to remove the signal suppressing and to avoid the possible overlapping. With this method, 9 possible PC molecules in crucian carp and the corresponding fatty acid compositions were given from the well-resolved mass spectra.

  14. Determination of vegetable tannins in tannery wastewater using RP-HPLC-technique with UV- and EC-detection; Bestimmung vegetabiler Gerbstoffe in Gerbereiabwasser unter Einsatz der RP-HPLC-Technik mit UV- und EC-Detektion

    Energy Technology Data Exchange (ETDEWEB)

    Zywicki, B.; Reemtsma, T.; Jekel, M. [Technische Univ. Berlin (Germany). Fachgebiet Wasserreinhaltung

    2001-07-01

    Numerous types of inorganic and organic environmental pollutants are encountered in leather tannery effluents. For reduction of the environmental impact of leather tanneries the substitution of chromium tanning agents by natural organic tanning agents (vegetable tannins) is discussed. The use of vegetable tannins leads to an elevated dissolved organic carbon content (DOC) in tannery effluent, even after biological treatment. Vegetable tannins may also be used as retanning agents, but they may, then interfere with precipitation of chromium. Therefore, an analytical method had to be established to estimate the total amount of vegetable tanning agents in the complex matrix of tannery wastewater. The analytical strategy for the determination of vegetable tannins in tannery effluents is to degrade the polyphenolic compounds by acid hydrolysis and to detect the resulting specific monomeric subunit gallic acid by RP-HPLC-technique with UV- and electrochemical detection (EC-detection). (orig.)

  15. Development of an HPLC post-column antioxidant assay for Solidago canadensis radical scavengers.

    Science.gov (United States)

    Marksa, Mindaugas; Radušienė, Jolita; Jakštas, Valdas; Ivanauskas, Liudas; Marksienė, Rūta

    2016-01-01

    The aim of this work was to modify and validate the post-column high-performance liquid chromatography (HPLC)-ABTS and DPPH methods for evaluating the antioxidant activity of the methanolic extracts of Solidago canadensis (Canadian goldenrod) leaves and flowers. Separation of the analytes was performed via the HPLC-PDA method on a YMC analytical column using a gradient elution program. Three compounds with antioxidant properties - chlorogenic acid, rutin and isoquercitrin - and two unidentified antioxidants were established. The research showed that the coil temperature regimes and loop length combinations influence the optimised post-column assay method for detecting the antioxidant activity of goldenrod radical scavengers. Investigations established that the temperature in the reaction coil was a substantial factor contributing to the signal strength of the analytes after reacting with the DPPH and ABTS radicals. PMID:25835071

  16. Discrimination of Black Ball-point Pen Inks by High Performance Liquid Chromatography (HPLC)

    International Nuclear Information System (INIS)

    In this study, thirteen types of black ball-point pen inks of three major brands were analyzed using high performance liquid chromatography (HPLC). Separation of the ink components was achieved using Bondapak C-18 column with gradient elution using water, ethanol and ethyl acetate. The chromatographic data obtained at wavelength 254.8 nm was analyzed using agglomerative hierarchical clustering (AHC) and principle component analysis (PCA). AHC was able to group the inks into three clusters. This result was supported by PCA, whereby distinct separation of the three different brands was achieved. Therefore, HPLC in combination with chemometric methods may be a valuable tool for the analysis of black ball-point pen inks for forensic purposes. (author)

  17. Chemical fingerprint and quantitative analysis for quality control of polyphenols extracted from pomegranate peel by HPLC.

    Science.gov (United States)

    Li, Jianke; He, Xiaoye; Li, Mengying; Zhao, Wei; Liu, Liu; Kong, Xianghong

    2015-06-01

    A simple and efficient HPLC fingerprint method was developed and validated for quality control of the polyphenols extracted from pomegranate peel (PPPs). Ten batches of pomegranate collected from different orchards in Shaanxi Lintong of China were used to establish the fingerprint. For the fingerprint analysis, 15 characteristic peaks were selected to evaluate the similarities of 10 batches of the PPPs. The similarities of the PPPs samples were all more than 0.968, indicating that the samples from different areas of Lintong were consistent. Additionally, simultaneous quantification of eight monophenols (including gallic acid, punicalagin, catechin, chlorogenic acid, caffeic acid, epicatechin, rutin, and ellagic acid) in the PPPs was conducted to interpret the consistency of the quality test. The results demonstrated that the HPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantitative analysis can be successfully used to assess the quality and to identify the authenticity of the PPPs. PMID:25624199

  18. SIMULTANEOUS ESTIMATION OF SAXAGLIPTIN HYDROCHLORIDE AND METFORMIN HYDROCHLORIDE IN ACTIVE PHARMACEUTICAL INGRIDENT BY RP-HPLC

    Directory of Open Access Journals (Sweden)

    NYOLA NARENDRA, GOVINDASAMY JEYABALAN

    2013-09-01

    Full Text Available A new simple, accurate, precise and reproducible RP-HPLC method has been developed for the simultaneousestimation of Saxagliptin and Metformin in bulk drug form using C18 column (Phenomenex, 250 x 4.6 mm, 5 μm inisocratic mode. The mobile phase consisted of 0.02M Potassium dihydrogen phosphate (KH2PO4, Acetonitrile,Methanol in the ratio of 50:25:25 (v/v/v at pH 4.3. The detection wavelength was carried out at 240 nm. Themethod was linear over the concentration range for Saxagliptin 10-50μg/ml and for Metformin 5-25 μg/ml. Therecoveries of Saxagliptin and Metformin were found to be 100.48and 101.1% respectively. The validation of methodwas carried out utilizing ICH-guidelines. The described HPLC method was successfully employed for the analysisof pharmaceutical formulations containing combined dosage form.

  19. Protein profile study of the cervical cancer using HPLC-LIF

    Science.gov (United States)

    Sujatha; Rai, Lavanya; Krishnanand, B. R.; Mahato, K. K.; Kartha, V. B.; C, Santhosh

    2006-02-01

    Optical methods and proteomics investigations are becoming promising approaches for early detection of many diseases, which remain clinically silent for long periods. We have used efficient High Performance Liquid Chromatography (HPLC) separation combined with highly sensitive laser induced fluorescence detection of proteins present in clinical samples for diagnostic applications in cervical cancer. The protein profile and the fluorescence of individual proteins were simultaneously recorded using our HPLC-LIF system. Protein profiles (Chromatogram) of serum from normal male and female volunteers with and without tobacco habits, and malignant serum samples were studied. Protein profiles were also recorded for lysates of exfoliated cells collected from Pap smear of normal and cancer patients. The protein profile patterns were subjected to Principal component Analysis. Discrimination of normal and malignant samples were achieved with very high sensitivity and specificity.

  20. RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF SEXAGLIPTIN AND PIOGLITAZONE IN TABLETS

    Directory of Open Access Journals (Sweden)

    M.Sarat

    2012-05-01

    Full Text Available A simple, selective, accurate high Performance Liquid Chromatographic (HPLC method was developed and validated for the analysis of Sexagliptin and Pioglitazone. Chromatographic separation achieved isocratically on a C18 column [Use Inertsil C18, 5m , 150 mm x 4.6 mm] utilizing a mobile phase of acetonitrile/phosphate buffer (60:40, v/v, pH 7.0 at a flow rate of 0.8 ml/min with UV detection at 260nm.Aceclofenac was used as an internal standard. The retention time of Sexagliptin, pioglitazone and aceclofenac was 2.48, 4.45 and 6.34 min respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantitation.This study aimed at developing and validating an HPLC method, being simple, accurate and selective, and the proposed method can be used for the estimation of these drugs in combined dosage forms.

  1. Analytical Method Development and Validation for Simultaneous Estimation of Clotrimazole and Tinidazole by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Joshi S

    2015-12-01

    Full Text Available An isocratic reverse phase High Performance Liquid Chromatographic (RP-HPLC method was developed and validated for simultaneous determination of Clotrimazole and Tinidazole in combined pharmaceutical dosage form. The successful separation of Clotrimazole and Tinidazole was achieved using Purospher® C18 (250 mm x 4.6 mm i.d., 5 μm column, with mobile phase consisting Phosphate buffer (pH 3.5: Acetonitrile (45:55. The mobile phase flow rate was 1.0 ml/min and the detection wavelength was 240 nm. The developed RP-HPLC method was validated according to ICH guidelines with respect to linearity, accuracy, precision, specificity and robustness and also the LOD and LOQ values were determined.

  2. High performance liquid chromatography (HPLC) applied to determination of oligosaccharides in irradiated beans (Vigna unguiculata (L.) Walp)

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Keila S. Cople; Souza, Luciana B.; Coelho, Maysa J.; Lima, Antonio L. Santos; Vital, Helio C. [Instituto Militar de Engenharia IME, Rio de Janeiro, RJ (Brazil). Secao de Engenharia Nuclear]. E-mail: keila@ime.eb.br; maysa@ime.eb.br; santoslima@ime.eb.br; Godoy, Ronoel L.O. [EMBRAPA Agroindustria de Alimentos, Rio de Janeiro, RJ (Brazil)]. E-mail: ronoel@ctaa.embrapa.br

    2007-07-01

    Beans are important components of Brazilian diet, especially for less affordable people. They have in their composition proteins, vitamins, carbohydrates, minerals and fibers. Despite of their high nutritional value, nonnutritive elements from natural origin are present in leguminous plants, such as raffinose and stachyose. The oligosaccharides are flatulence agents due to bacterial anaerobic fermentation at the intestines. The aim of this study is to evaluate the effect of combined boiling and gamma irradiation treatments on fradinho-beans (Vigna unguiculata (L.) Walp) with respect to oligosaccharide contents. The irradiation process was performed at the Nuclear Defense Section of Brazilian Army, using a cavity type research irradiator, which has a Cs-137 radiation source and maximum dose rate of 1.8 kGy/h. The oligosaccharides were evaluated by HPLC technique, at 'EMBRAPA Agroindustria de Alimentos', using a SHIMADZU liquid chromatography system, with a refraction index detector Waters 2421. The mobile phase was acetonitrile 70% in water for raffinose and stachyose and 80% for saccharose. The flux and the running time were 1 mL/min and 18 minutes for raffinose and stachyose, and 1.3 mL/min and 20 minutes for saccharose. The injection volume was 20 {mu}L and the column used (Waters 250 x 4,6 mm; 4 mm) was kept at room temperature. The evaluation of unboiled irradiated beans showed that there was no significant difference between the different irradiation doses and control sample, keeping the oligosaccharide contents. However, the combination of the boiling and the irradiation processes turned out to reduce of non-nutritive factors that may cause flatulence, meaning a real benefit to the consumers. (author)

  3. High performance liquid chromatography (HPLC) applied to determination of oligosaccharides in irradiated beans (Vigna unguiculata (L.) Walp)

    International Nuclear Information System (INIS)

    Beans are important components of Brazilian diet, especially for less affordable people. They have in their composition proteins, vitamins, carbohydrates, minerals and fibers. Despite of their high nutritional value, nonnutritive elements from natural origin are present in leguminous plants, such as raffinose and stachyose. The oligosaccharides are flatulence agents due to bacterial anaerobic fermentation at the intestines. The aim of this study is to evaluate the effect of combined boiling and gamma irradiation treatments on fradinho-beans (Vigna unguiculata (L.) Walp) with respect to oligosaccharide contents. The irradiation process was performed at the Nuclear Defense Section of Brazilian Army, using a cavity type research irradiator, which has a Cs-137 radiation source and maximum dose rate of 1.8 kGy/h. The oligosaccharides were evaluated by HPLC technique, at 'EMBRAPA Agroindustria de Alimentos', using a SHIMADZU liquid chromatography system, with a refraction index detector Waters 2421. The mobile phase was acetonitrile 70% in water for raffinose and stachyose and 80% for saccharose. The flux and the running time were 1 mL/min and 18 minutes for raffinose and stachyose, and 1.3 mL/min and 20 minutes for saccharose. The injection volume was 20 μL and the column used (Waters 250 x 4,6 mm; 4 mm) was kept at room temperature. The evaluation of unboiled irradiated beans showed that there was no significant difference between the different irradiation doses and control sample, keeping the oligosaccharide contents. However, the combination of the boiling and the irradiation processes turned out to reduce of non-nutritive factors that may cause flatulence, meaning a real benefit to the consumers. (author)

  4. Antifungal agents.

    Science.gov (United States)

    Ryder, N S

    1999-12-01

    At this year's ICAAC Meeting, new data on approximately 20 different antifungal agents were presented, while no new agents were disclosed. Drugs in late development include the triazoles, voriconazole (Pfizer Ltd) and Sch-56592 (Schering-Plough Corp), and the echinocandins, caspofungin (Merck & Co Inc) and FK-463 (Fujisawa Pharmaceutical Co Ltd). In contrast to previous years, presentations on these and earlier developmental compounds were relatively modest in scope, with few significant new data. Little new information appeared on the most recent novel class of agents, the sordarins (Glaxo Wellcome plc). Early clinical results were presented for FK-463, showing acceptable tolerability and dose-dependent efficacy in AIDS-associated esophageal candidiasis. A new liposomal formulation of nystatin (Nyotran; Aronex Pharmaceuticals Inc) was shown to be equivalent to conventional amphotericin B in empiric therapy of presumed fungal infection in neutropenic patients, but with reduced toxicity. Intravenous itraconazole (Janssen Pharmaceutica NV) was an effective prophylactic therapy in invasive pulmonary aspergillosis, while oral itraconazole was discussed as a treatment for fungal infection in heart and liver transplant patients. The allylamine compound, terbinafine (Novartis AG), showed good clinical efficacy against fungal mycetoma, a serious tropical infection. A major highlight was the first presentation of inhibitors of fungal efflux pumps as a strategy for overcoming resistance. MC-510027 (milbemycin alpha-9; Microcide Pharmaceuticals Inc) and its derivatives, potentiated the antifungal activity of triazoles and terbinafine in a number of Candida spp. Another pump inhibitor, MC-005172 (Microcide Pharmaceuticals Inc) showed in vivo potentiation of fluconazole in a mouse kidney infection model. Microcide Pharmaceuticals Inc also presented inhibitors of bacterial efflux pumps. PMID:16113946

  5. Topical agents in burn care

    Directory of Open Access Journals (Sweden)

    Momčilović Dragan

    2002-01-01

    Full Text Available Introduction Understanding of fluid shifts and recognition of the importance of early and appropriate fluid replacement therapy have significantly reduced mortality in the early post burn period. After the bum patient successfully passes the resuscitation period, the burn wound represents the greatest threat to survival. History Since the dawn of civilization, man has been trying to find an agent which would help burn wounds heal, and at the same time, not harm general condition of the injured. It was not until the XX century, after the discovery of antibiotics, when this condition was fulfilled. In 1968, combining silver and sulfadiazine, fox made silver-sulfadiazine, which is a 1% hydro-soluble cream and a superior agent in topical treatment of burns today. Current topical agents None of the topical antimicrobial agents available today, alone or combined, have the characteristics of ideal prophylactic agents, but they eliminate colonization of burn wound, and invasive infections are infrequent. With an excellent spectrum of activity, low toxicity, and ease of application with minimal pain, silver-sulfadiazine is still the most frequently used topical agent. Conclusion The incidence of invasive infections and overall mortality have been significantly reduced after introduction of topical burn wound antimicrobial agents into practice. In most burn patients the drug of choice for prophylaxis is silver sulfadiazine. Other agents may be useful in certain clinical situations.

  6. Determination of boron in nuclear materials at subppm levels by high pressure liquid chromatography (HPLC)

    International Nuclear Information System (INIS)

    Experiments were conducted for the determination of boron in U3O8 powder, aluminium metal and milliQ water using dynamically modified Reversed Phase High Pressure Liquid Chromatography (RP-HPLC) and using two precolumn chromogenic agents viz. chromotropic acid and curcumin for complexing boron. The complex was separated from the excess of reagent and determined by HPLC. When present in subppm levels, chromotropic acid was used successfully only for determination boron in water samples. For determination of boron at subppm levels in uranium and aluminium samples, curcumin was used as the precolumn chromogenic agent. The boron curcumin complex (rosocyanin) was formed after extraction of boron with 2-ethyl-l, 3-hexane diol (EHD). The rosocyanin complex was then separated from excess curcumin by displacement chromatography. Linear calibration curves for boron amounts in the range of 0.02 μg to 0.5 μg were developed with correlation coefficients varying from 0.997 to 0.999 and were used for the determination of boron in aluminium and uranium samples. Precision of about 10% was achieved in samples containing less than 1 ppmw of boron. Detection limit of this method is 0.01 μg boron. (author)

  7. Trading Agents

    CERN Document Server

    Wellman, Michael

    2011-01-01

    Automated trading in electronic markets is one of the most common and consequential applications of autonomous software agents. Design of effective trading strategies requires thorough understanding of how market mechanisms operate, and appreciation of strategic issues that commonly manifest in trading scenarios. Drawing on research in auction theory and artificial intelligence, this book presents core principles of strategic reasoning that apply to market situations. The author illustrates trading strategy choices through examples of concrete market environments, such as eBay, as well as abst

  8. Interaction Protocols in Multi-Agent Systems based on Agent Petri Nets Model

    Directory of Open Access Journals (Sweden)

    Kamel Barkaoui

    2013-08-01

    Full Text Available This paper deals with the modeling of interaction between agents in Multi Agents System (MAS based on Agent Petri Nets (APN. Our models are created based on communicating agents. Indeed, an agent initiating a conversation with other can specify the interaction protocol wishes to follow. The combination of APN and FIPA Protocols schemes leads to a set of deployment formal rules for points where model interaction can be successfully implemented. We introduce some models FIPA standard protocols.

  9. Agent planning in AgScala

    Science.gov (United States)

    Tošić, Saša; Mitrović, Dejan; Ivanović, Mirjana

    2013-10-01

    Agent-oriented programming languages are designed to simplify the development of software agents, especially those that exhibit complex, intelligent behavior. This paper presents recent improvements of AgScala, an agent-oriented programming language based on Scala. AgScala includes declarative constructs for managing beliefs, actions and goals of intelligent agents. Combined with object-oriented and functional programming paradigms offered by Scala, it aims to be an efficient framework for developing both purely reactive, and more complex, deliberate agents. Instead of the Prolog back-end used initially, the new version of AgScala relies on Agent Planning Package, a more advanced system for automated planning and reasoning.

  10. Intelligent Farmer Agent for Multi-Agent Ecological Simulations Optimization

    OpenAIRE

    Filipe Cruz; António Pereira; Pedro Valente; Pedro Duarte; Luis Paulo Reis

    2007-01-01

    This paper presents the development of a bivalve farmer agent interacting with a realistic ecological simulation system. The purpose of the farmer agent is to determine the best combinations of bivalve seeding areas in a large region, maximizing the production without exceeding the total allowed seeding area. A system based on simulated annealing, tabu search, genetic algorithms and reinforcement learning, was developed to minimize the number of iterations required to unravel a semi-optimum s...

  11. Radioprotective Agents

    Directory of Open Access Journals (Sweden)

    Ilker Kelle

    2008-01-01

    Full Text Available Since1949, a great deal of research has been carried out on the radioprotective activity of various chemical substances. Thiol compounds, compounds which contain –SH radical, different classes of pharmacological agents and other compounds such as vitamine C and WR-2721 have been shown to reduce mortality when administered prior to exposure to a lethal dose of radiation. Recently, honey bee venom as well as that of its components melittin and histamine have shown to be valuable in reduction of radiation-induced damage and also provide prophylactic alternative treatment for serious side effects related with radiotherapy. It has been suggested that the radioprotective activity of bee venom components is related with the stimulation of the hematopoetic system.

  12. Fingerprint of Hedyotis diffusa Willd. by HPLC-MS.

    Science.gov (United States)

    Yang, Ting; Yang, Yi-Hua; Yang, Ju-Yun; Chen, Ben-Mei; Duan, Ju-Ping; Yu, Shu-Yi; Ouyang, Hong-Tao; Cheng, Jun-Ping; Chen, Yu-Xiang

    2008-01-01

    A HPLC-MS fingerprint method has been developed based on the consistent chromatographic features of the major chemical constituents among 10 batches of Hedyotis diffusa Willd. Chromatographic separation was conducted on a Hypersil-Keystone Hypurity C(18) column using methanol:water:acetic acid as the mobile phase. Major compounds, including oleanolic acid, ursolic acid and ferulic acid, were analysed by HPLC-MS. Their analysis was ascertained by comparison with data derived from the standard compounds. The HPLC-MS fingerprint was successfully applied to analyse and differentiate samples from different geographical origins, or processing methods. H. diffusa was well distinguished from Hedyotis chrysotricha by HPLC-MS. Therefore the establishment of fingerprint of H. diffusa is critical in assessing and controlling its overall quality. PMID:18446772

  13. Automated HPLC monitoring of broth components on bioreactors

    OpenAIRE

    Favre, Eric; Pugeaud, Patrick; Raboud, Jean Philippe; Péringer, Paul

    1989-01-01

    Under proper operating conditions, a low dead volume continuous filtration module operated on biological broths (yeast and bacteria suspensions in stirred reactors) still fulfills the flow-rate requirements of an analytical apparatus (for example HPLC or FIA) without membrane regeneration. The filtrate stream has been successfully connected to a bioreactor in order to perform the automated HPLC analysis of broth components. The monitoring of the carbon source (lactose), and minor products (gl...

  14. An agent framework for dynamic agent retraining: Agent academy

    OpenAIRE

    Mitkas, P.; A. Symeonidis; Kechagias, D.; Athanasiadis, I.N.; Laleci, G.; KURT, G.; Kabak, Y.; Acar, A.; Dogac, A.

    2004-01-01

    Agent Academy (AA) aims to develop a multi-agent society that can train new agents for specific or general tasks, while constantly retraining existing agents in a recursive mode. The system is based on collecting information both from the environment and the behaviors of the acting agents and their related successes/failures to generate a body of data, stored in the Agent Use Repository, which is mined by the Data Miner module, in order to generate useful knowledge about the application domai...

  15. Vergelijking van HPLC-methoden voor de bepaling van pentachloorfenol in houtmonsters

    OpenAIRE

    Goewie; C.E.; Berkhoff; Der, C J

    1986-01-01

    Een vergelijkend onderzoek is verricht naar de bruikbaarheid van verschillende detectiemethoden in combinatie met HPLC voor de analyse van pentachloorfenol in hout. In het onderzoek wordt RP-HPLC met UK en amperometrische detectie beschreven, evenals NP-HPLC met elektroneninvangdetectie. In verschillende houtmonsters kon m.b.v. de NP-HPLC met electroneninvangdetectie 1-50 ppm pentachloorfenol worden aangetoond.

  16. Engagement driven Topic Selection for an Information-Giving Agent

    OpenAIRE

    Glas, Nadine; Prepin, Ken; Pelachaud, Catherine

    2015-01-01

    International audience We propose a model for conversational agents to select the topic of interaction in agent-initiated information-giving chat. By taking into account the agent's dynamically updated perception of the user's engagement, the agent's own preferences and its associations between topics, the agent tries to select the topic that max-imises the agent and user's combined engagement. The model offers engagement driven dialogue management on the topic level.

  17. Secure Mobile Trade Agent

    Directory of Open Access Journals (Sweden)

    Musbah M. Aqe

    2007-01-01

    Full Text Available E-commerce on the internet has the ability to produce millions of transactions and a great number of merchants whose supply merchandise over the internet. As a result, it is difficult for entities to roam over every site on the internet and choose the best merchandise to trade. So, in this paper we introduced a mobile trade agent that visit the sites to gather and evaluate the information from merchant servers and decide to trade goods on behalf of the user. We observed that the combination of public key cryptosystem with distributed object technology make this proposed scheme more secure and efficient than the already existed schemes.

  18. RP-HPLC method for the simultaneous determination of Atorvastatin and Amlodipine in tablet dosage form

    Directory of Open Access Journals (Sweden)

    Rajeswari K

    2006-01-01

    Full Text Available A simple, precise, accurate, and rapid HPLC method has been developed, and validated for the determination of atorvastatin and amlodipine simultaneously, in combined tablet dosage form. The mobile phase used was a mixture of acetonitrile and 0.03M phosphate buffer pH 2.9 (55:45% v/v. The detection of atorvastatin and amlodipine was carried out on dual g absorbance detector at 240 nm and 362 nm, respectively. Results of the analysis were validated statistically, and by recovery studies. The proposed method can be successfully used to determine the drug contents of marketed formulation.

  19. Learning other agents` preferences in multiagent negotiation

    Energy Technology Data Exchange (ETDEWEB)

    Bui, H.H.; Kieronska, D.; Venkatesh, S. [Curtin Univ. of Technology, Perth, WA (Australia)

    1996-12-31

    In multiagent systems, an agent does not usually have complete information about the preferences and decision making processes of other agents. This might prevent the agents from making coordinated choices, purely due to their ignorance of what others want. This paper describes the integration of a learning module into a communication-intensive negotiating agent architecture. The learning module gives the agents the ability to learn about other agents` preferences via past interactions. Over time, the agents can incrementally update their models of other agents` preferences and use them to make better coordinated decisions. Combining both communication and learning, as two complement knowledge acquisition methods, helps to reduce the amount of communication needed on average, and is justified in situations where communication is computationally costly or simply not desirable (e.g. to preserve the individual privacy).

  20. Analysis of natural red dyes (cochineal) in textiles of historical importance using HPLC and multivariate data analysis.

    Science.gov (United States)

    Serrano, Ana; Sousa, Micaela M; Hallett, Jessica; Lopes, João A; Oliveira, M Conceição

    2011-08-01

    A new analytical approach based on high-performance liquid chromatography with diode array detector (HPLC-DAD) and multivariate data analysis was applied and assessed for analyzing the red dye extracted from cochineal insects, used in precious historical textiles. The most widely used method of analysis involves quantification of specific minor compounds (markers), using HPLC-DAD. However, variation in the cochineal markers concentration, use of aggressive dye extraction methods and poor resolution of HPLC chromatograms can compromise the identification of the precise insect species used in the textiles. In this study, a soft extraction method combined with a new dye recovery treatment was developed, capable of yielding HPLC chromatograms with good resolution, for the first time, for historical cochineal-dyed textiles. After principal components analysis (PCA) and mass spectrometry (MS), it was possible to identify the cochineal species used in these textiles, in contrast to the accepted method of analysis. In order to compare both methodologies, 7 cochineal species and 63 historical cochineal insect specimens were analyzed using the two approaches, and then compared with the results for 15 historical textiles in order to assess their applicability to real complex samples. The methodology developed here was shown to provide more accurate and consistent information than the traditional method. Almost all of the historical textiles were dyed with Porphyrophora sp. insects. These results emphasize the importance of adopting the proposed methodology for future research on cochineal (and related red dyes). Mild extraction methods and HPLC-DAD/MS(n) analysis yield distinctive profiles, which, in combination with a PCA reference database, are a powerful tool for identifying red insect dyes. PMID:21626194

  1. Isolation and quantification of a new tuliposide (tuliposide D) by HPLC in Alstroemeria.

    Science.gov (United States)

    Christensen, L P; Kristiansen, K

    1995-09-01

    From aqueous extracts of flowers, stems and leaves of 1 Brazilian and 15 Chilean Alstroemeria species, the content of a new tuliposide, named tuliposide D, was determined by isocratic reversed-phase high-performance liquid chromatography (RP-HPLC), using distilled water:methanol (80:20) as mobile phase. The compound was detected by a UV-detector at 208 nm. Tuliposide D was found in almost all Alstroemeria species investigated, although in very different amounts. Most species contained relatively small amounts of tuliposide D, especially in the leaves. However, A. hookeri ssp. cummingiana, A. presliana ssp. presliana, A. pseudospathulata and A. revoluta contained large amounts of tuliposide D in all plant parts. Tuliposide D was identified as 1,6-di-(4-hydroxy-2-methylenebutanoate)-beta-D-glucopyranose by UV, FAB-MS, 1H- and 13C-NMR. The content of the allergens 6-tuliposide A and tulipalin A was also determined by RP-HPLC and the possibility that tuliposide D is a further causative agent of allergic contact dermatitis in Alstroemeria is discussed. PMID:8565461

  2. HPLC study on the stability of bendamustine hydrochloride immobilized onto polyphosphoesters.

    Science.gov (United States)

    Pencheva, Ivanka; Bogomilova, Anita; Koseva, Neli; Obreshkova, Danka; Troev, Kolio

    2008-12-01

    Novel water soluble polymer complexes of bendamustine hydrochloride, a bifunctional alkylating agent with antimetabolic and cytotoxic activity, were developed using biodegradable polymer carriers-poly(oxyethylene H-phosphonate), poly(methyloxyethylene phosphate) and poly(hydroxyoxyethylene phosphate). Bendamustine hydrochloride was immobilized onto polyphosphoesters via covalent, ionic and hydrogen bonding. The structure of the complexes formed was elucidated by (1)H, (13)C, (31)P NMR and FT-IR spectroscopy. The chemical stability of bendamustine hydrochloride in the novel complexes was studied by HPLC analysis based on a validated method with appointed analytical parameters such as specificity, repeatability, limit of quantitation, limit of detection and linearity. The results from the HPLC indicate that in neutral (pH 7) and alkaline (pH 9) media bendamustine hydrochloride in the polymer complexes is more stable than the pure bendamustine hydrochloride. The enhanced stability of the immobilized drug is explained with the drug interaction with the polymer carriers or their degradation products. PMID:18926656

  3. Possible interferences of mercury sulfur compounds with ethylated and methylated mercury species using HPLC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Wilken, R.D.; Nitschke, F.; Falter, R. [ESWE-Institute for Water Research Water Technology at Mainz University, Kurfuerstenstr. 6, 65203, Wiesbaden (Germany)

    2003-09-01

    The HPLC-ICP-MS coupling technique is able to separate and detect methyl, ethyl and inorganic mercury isotopes specifically. An identification of ethyl mercury(+) is not possible when the widely used sodium tetraethylborate derivatisation method in combination with GC-AFS/AAS or ICP-MS techniques is performed because it contains ethyl groups. An unidentified compound with the same retention time as ethyl mercury was found in the HPLC chromatograms of industrial sewage samples and humic-rich soils of microcosm experiments after applying water vapour distillation. We also observed such unidentified peaks in samples of heavily contaminated sites in Eastern Germany, separated by HPLC fractionation only. In the experiments described, different mercury sulfur adducts were synthesised and tested for their retention times in the HPLC-ICP-MS system. It was found that the compound CH{sub 3}-S-Hg{sup +} showed the same retention time as the ethyl mercury standard. It is therefore possible that ethyl mercury detected in chromatography by comparison of the retention time could also be due to an adduct of a sulfur compound and a mercury species. CH{sub 3}-S-Hg{sup +}should be tested in other chromatographic mercury speciation methods for this effect. This work can also be regarded as a contribution to the discussion of artificially occurring methyl mercury in sediments during sample preparation. (orig.)

  4. Possible interferences of mercury sulfur compounds with ethylated and methylated mercury species using HPLC-ICP-MS

    International Nuclear Information System (INIS)

    The HPLC-ICP-MS coupling technique is able to separate and detect methyl, ethyl and inorganic mercury isotopes specifically. An identification of ethyl mercury(+) is not possible when the widely used sodium tetraethylborate derivatisation method in combination with GC-AFS/AAS or ICP-MS techniques is performed because it contains ethyl groups. An unidentified compound with the same retention time as ethyl mercury was found in the HPLC chromatograms of industrial sewage samples and humic-rich soils of microcosm experiments after applying water vapour distillation. We also observed such unidentified peaks in samples of heavily contaminated sites in Eastern Germany, separated by HPLC fractionation only. In the experiments described, different mercury sulfur adducts were synthesised and tested for their retention times in the HPLC-ICP-MS system. It was found that the compound CH3-S-Hg+ showed the same retention time as the ethyl mercury standard. It is therefore possible that ethyl mercury detected in chromatography by comparison of the retention time could also be due to an adduct of a sulfur compound and a mercury species. CH3-S-Hg+should be tested in other chromatographic mercury speciation methods for this effect. This work can also be regarded as a contribution to the discussion of artificially occurring methyl mercury in sediments during sample preparation. (orig.)

  5. Application of artificial neural networks for response surface modelling in HPLC method development

    Directory of Open Access Journals (Sweden)

    Mohamed A. Korany

    2012-01-01

    Full Text Available This paper discusses the usefulness of artificial neural networks (ANNs for response surface modelling in HPLC method development. In this study, the combined effect of pH and mobile phase composition on the reversed-phase liquid chromatographic behaviour of a mixture of salbutamol (SAL and guaiphenesin (GUA, combination I, and a mixture of ascorbic acid (ASC, paracetamol (PAR and guaiphenesin (GUA, combination II, was investigated. The results were compared with those produced using multiple regression (REG analysis. To examine the respective predictive power of the regression model and the neural network model, experimental and predicted response factor values, mean of squares error (MSE, average error percentage (Er%, and coefficients of correlation (r were compared. It was clear that the best networks were able to predict the experimental responses more accurately than the multiple regression analysis.

  6. Agent Chameleons: Virtual Agents Real Intelligence

    OpenAIRE

    O'Hare, Gregory; Duffy, Brian; Schoen-Phelan, Bianca; Martin, Alan; Bradley, John

    2003-01-01

    Agent Chameleons provides virtual agents powered by real intelligence, delivering next generation autonomic entities that can seamlessly migrate, mutate and evolve on their journey between and within physical and digital information spaces.

  7. HPLC-DAD Method for the Pharmacokinetic Interaction Study of Atorvastatin with Pioglitazone and Cholestyramine in Wistar Rats

    OpenAIRE

    SHARMA, RITESH N.; Pancholi, Shyam S.

    2014-01-01

    Abstract Carotid intima-media thickness is used as a surrogate marker for cardiovascular complications in diabetes mellitus. The combination of atorvastatin and pioglitazone was found to be effective in reducing the thickness of the carotid intima-media layer. The method of RP-HPLC coupled with a diode array detector (DAD) was developed for the pharmacokinetic interaction study of atorvastatin with pioglitazone and cholestyramine, respectively, in Wistar rats. Atorvastatin (ATR) and pioglitaz...

  8. In vitro duodenal lipolysis of lipid-based drug delivery systems studied by HPLC-UV and HPLC-MS.

    Science.gov (United States)

    Wulff-Pérez, Miguel; Barrajón-Catalán, Enrique; Micol, Vicente; Martín-Rodríguez, Antonio; de Vicente, Juan; Gálvez-Ruíz, María J

    2014-04-25

    Oral drug delivery systems based on lipids are biodegraded in a process called lipolysis to release free fatty acids and monoglycerides. The rate of this lipolysis is usually measured by pH titration. Nevertheless, this technique has some limitations, such as not providing any information about the actual composition of the lipolytic products. In this study, we propose a method to analyze these products during and after lipolysis using HPLC. For the first time, HPLC-UV and HPLC-MS have been used to investigate in vitro duodenal lipolysis of long- and medium-chain triglycerides nanoemulsions. These results have been compared with pH titration, revealing the complementarity of both techniques. The main free fatty acids and monoglycerides produced were effectively identified and quantified as they were formed and after the lipolysis experiment and subsequent ultracentrifugation. The release of fatty acids during lipolysis was qualitatively similar between the compared techniques, although a partial precipitation of medium chain fatty acids could be revealed with HPLC-MS. In addition, the release of two hydrophobic compounds with health benefits, oleoylethanolamide and carnosic acid, was investigated. In conclusion, this study may serve as a starting point for subsequent investigations regarding biodegradation and absorption of lipid-based drug delivery systems using HPLC. PMID:24560636

  9. Mercury speciation analysis in marine samples by HPLC-ICPMS

    DEFF Research Database (Denmark)

    Rasmussen, Rie Romme; Svendsen, Maja Erecius; Herbst, M. Birgitte Koch;

    exposure to methylmercury is mainly from fish and other seafood consumption. A simple method for the determination of methylmercury in marine based foods and feeds has been developed and in-house validated. The applied HPLC-ICPMS method was inspired by Vallant et al (2007). Samples were extracted with 5 M...... the mobile phase and filtering prior to analysis. Analysis of mercury species were performed using HPLC-ICPMS equipped with a MicroMist nebuliser. Typical plasma conditions were 1500 W RF power, 15 l/min, 0.97 l/min and 0.17 l/min for plasma, carrier and makeup gas, respectively, Analysis was...

  10. A New HPLC Method to Determine Carbonyl Compounds in Air

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper, a new HPLC method was established to determine the carbonyl compounds in air. As the absorbent, 2, 4-dinitrophenylhydrazine (2, 4-DNPH) reacted with carbonyls specifically, which form the corresponding 2,4-dinitrophenylhydrazones, then analyzed by HPLC. The chromatographic conditions, the recovery rate, stability of samples, reagent blank, sampling efficiency were all studied systematically. The results showed that this established method had high sensitivity and good selectivity compared with other analytical methods, and it can determine ten carbonyl compounds in air in 26 min simultaneously.

  11. HPLC ANALYSIS Of Adhatoda Vasica OBTAINED FROM DIFFERENT GEOGRAPHICAL SOURCES

    Directory of Open Access Journals (Sweden)

    Smriti Muralidhar

    2010-12-01

    Full Text Available Vasicine is one of the important alkaloid obtained from the plant Adhatoda vasica. In the present study, the drug was collected from five accessions namely Bangalore, Shimoga, Trichy, Kolhapur and Palakkad (Kerala between August and November. The Methanolic extracts were used for HPLC analysis. The results of the HPLC analysis showed variations in all the accessions. The extract from Bangalore accession showed significantly higher amount of Vasicine (0.93% and that of Palakkad (Kerala showed least amount (0.59% of Vasicine.

  12. Immunological detection and quantification of DNA components structurally modified by alkylating carcinogens, mutagens and chemotherapeutic agents

    International Nuclear Information System (INIS)

    The detection and quantification of defined reaction products of chemical mutagens and carcinogens (and of many cancer chemotherapeutic agents) with DNA require highly sensitive analytical techniques. The exceptional capability of immunoglobulins to recognize subtle alterations of molecular structure (especially when monoclonal antibodies are used to maximize specificity), outstanding sensitivity of immunoanalysis by high-affinity antibodies, and the fact that radioactively-labelled agents are not required suggest the utility of a radioimmunoassay to recognize and quantitate alkylated DNA products. We have recently developed a set of high-affinity monoclonal antibodies (secreted by mouse x mouse as well as by rat x rat hybridomas; antibody affinity constants, 109 to > 1010 lmol) specifically directed against several DNA alkylation products with possible relevance in relation to both mutagenesis and malignant transformation of mammalian cells. These alkylation products include 06-N-butyldeoxyguanosine, and 04-ethyldeoxythymidine. When used in a radioimmunassay, an antibody specific for 06-ethyldeoxyguanosine, for example, will detect this product at an 06-ethyldeoxyguanosine/deoxyguanosine molar ratio of approx. 3 x 10-7 in a hydrolysate of 100 ug of DNA. The limit of detection can be lowered further if the respective alkyldeoxynucleosides are separated by HPLC from the DNA hydrolysate prior to the RIA. The anti-alkyldeoxynucleoside monoclonal antibodies can also be used to visualize, by immunostaining and fluorescence microscopy combined with electronic image intensification, specific alkylation products in the nuclear DNA of individual cells, and to localize structurally modified bases in double-stranded DNA molecules by transmission electron microscopy

  13. Agent-Oriented Probabilistic Logic Programming

    Institute of Scientific and Technical Information of China (English)

    Jie Wang; Shi-Er Ju; Chun-Nian Liu

    2006-01-01

    Currently, agent-based computing is an active research area, and great efforts have been made towards the agent-oriented programming both from a theoretical and practical view. However, most of them assume that there is no uncertainty in agents' mental state and their environment. In other words, under this assumption agent developers are just allowed to specify how his agent acts when the agent is 100% sure about what is true/false. In this paper, this unrealistic assumption is removed and a new agent-oriented probabilistic logic programming language is proposed, which can deal with uncertain information about the world. The programming language is based on a combination of features of probabilistic logic programming and imperative programming.

  14. An Agent Framework of Tourism Recommender System

    Directory of Open Access Journals (Sweden)

    Jia Zhi Yang

    2016-01-01

    Full Text Available This paper proposes the development of an Agent framework for tourism recommender system. The recommender system can be featured as an online web application which is capable of generating a personalized list of preference attractions for tourists. Traditional technologies of classical recommender system application domains, such as collaborative filtering, content-based filtering and content-based filtering are effectively adopted in the framework. In the framework they are constructed as Agents that can generate recommendations respectively. Recommender Agent can generate recommender information by integrating the recommendations of Content-based Agent, collaborative filtering-based Agent and constraint-based Agent. In order to make the performance more effective, linear combination method of data fusion is applied. User interface is provided by the tourist Agent in form of webpages and mobile app.

  15. HPLC-MS technique in radiopharmaceutical research (the quality control of 18F-2-fluorodeoxyglucose as an example)

    International Nuclear Information System (INIS)

    Application of radiopharmaceuticals puts increasing demands on their quality control, considering the short half-times, high specific activities (auto-radiolytic effects), and general quality (chemical purity, apyrogenity and sterility) of pharmacy. Mostly, the radioanalytical control consists of application of several separation and instrumental analytical techniques. In this paper, perspective of the hyphenated HPLC and MS techniques is demonstrated on the example of one of the most spread radiopharmaceutical, 2-[18F]fluoro-2-deoxy-D-glucose (further as FDG). In this work, a liquid chromatography/refractive index detector/radiometric detector/mass spectrometric detector combination (HPLC/RID/RAD/MSD) was used for development of a complex routine technique. Optimization of HPLC/MS analysis was performed investigating the electrospray ionization (ESI) analytical signal of mass spectrometer as a function of various eluent composition (see this book, p. 39). Some results, illustrating the glucose and FDG ESI-MS, and also composition of FDG after autoradiolysis, which were obtained either by a TOF Mariner (Perkin Elmer) mass-spectrometer and Agilent 1100 HPLC-MS equipment with quadrupole MS detector are discussed. They give evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloroglucose, erythrose, erytritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[19F]FDG, xylitol, and also univalent ions of C6H10O7F.H2O and C6H12O8 compounds. The results indicate that the emerging demands on radiopharmaceuticals quality control can be fulfilled in-time only by the radio-HPLC technique developed by the help of a tandem mass-spectrometric detector. (authors)

  16. Chemical fingerprinting and quantitative analysis of a Panax notoginseng preparation using HPLC-UV and HPLC-MS

    Directory of Open Access Journals (Sweden)

    Shao Qing

    2011-02-01

    Full Text Available Abstract Background Xuesaitong (XST injection, consisting of total saponins from Panax notoginseng, was widely used for the treatment of cardio- and cerebro-vascular diseases in China. This study develops a simple and global quality evaluation method for the quality control of XST. Methods High performance liquid chromatography-ultraviolet detection (HPLC-UV was used to identify and quantify the chromatographic fingerprints of the XST injection. Characteristic common peaks were identified using HPLC with photo diode array detection/electrospray ionization tandem mass spectrometry (HPLC-PDA/ESI-MSn. Results Representative fingerprints from ten batches of samples showed 27 'common saponins' all of which were identified and quantified using ten reference saponins. Conclusion Chemical fingerprinting and quantitative analysis identified most of the common saponins for the quality control of P. notoginseng products such as the XST injection.

  17. Identification and quantification of coumarins in Peucedanum ostruthium (L.) Koch by HPLC-DAD and HPLC-DAD-MS.

    Science.gov (United States)

    Vogl, Sylvia; Zehl, Martin; Picker, Paolo; Urban, Ernst; Wawrosch, Christoph; Reznicek, Gottfried; Saukel, Johannes; Kopp, Brigitte

    2011-05-11

    The rhizomes of Peucedanum ostruthium (L.) Koch (masterwort) are traditionally used in the alpine region as ingredient of liqueurs and bitters, and as a herbal drug. A sensitive and specific high-performance liquid chromatography-diode-array detection-mass spectrometry (HPLC-DAD-MS) method has been developed for the simultaneous identification and quantification of its main coumarins, oxypeucedanin hydrate, oxypeucedanin, ostruthol, imperatorin, osthole, isoimperatorin, and ostruthin. Fast HPLC separation could be achieved on an Acclaim C18 column (150 mm × 2.1 mm i.d., 3 μm) using a mobile phase gradient of acetonitrile-water modified with 0.01% acetic acid. The quantification by HPLC-DAD was performed with imperatorin as external standard and validated to demonstrate selectivity, linearity, precision, and accuracy. The content of the main coumarins was quantitated in various batches of commercial and field-collected rhizomes of Peucedanum ostruthium, as well as in beverages prepared thereof. PMID:21425828

  18. Comparison of direct injection nebulizer and desolvating microconcentric nebulizer for analysis of chlorine-, bromine- and iodine-containing compounds by reversed phase HPLC with ICP-MS detection

    DEFF Research Database (Denmark)

    Jensen, B.P.; Gammelgaard, Bente; Hansen, S.H.;

    2003-01-01

    With the purpose of finding ways to combine micro-bore reversed phase HPLC with ICP-MS detection for analysis of drug substances containing chlorine, bromine and iodine, the suitability of a direct injection nebulizer and an Aridus desolvating microconcentric nebulizer was compared. Using the...

  19. Development of a triple hyphenated HPLC-radical scavenging detection-DAD-SPE-NMR system for the rapid identification of antioxidants in complex plant extracts

    NARCIS (Netherlands)

    Pukalskas, A.; Beek, van T.A.; Waard, de P.

    2005-01-01

    A rapid method for the simultaneous detection and identification of radical scavenging compounds in plant extracts was developed by combining an HPLC with on-line radical scavenging using DPPH as a model radical and an HPLC¿DAD¿SPE¿NMR system. Using this method a commercial rosemary extract was inve

  20. High performance liquid chromatography (HPLC) fingerprints and primary structure identification of corn peptides by HPLC-diode array detection and HPLC-electrospray ionization tandem mass spectrometry

    OpenAIRE

    Chi Wang; Hui He; Jiu-liang Zhang; Xing Li; Zhi-li Ma

    2016-01-01

    Corn peptides (CPs) are reported to have many biological functions, such as facilitating alcohol metabolism, antioxidation, antitumor, antihypertension, and hepatoprotection. To develop a method for quality control, the high-performance liquid chromatography (HPLC) system was applied. Twenty-eight common peaks were found in all the CPs of corn samples from Enshi, China, based on which, a fingerprinting chromatogram was established for use in quality control in future research. Subsequently, t...

  1. Qualitative and Quantitative Analysis of Lignan Constituents in Caulis Trachelospermi by HPLC-QTOF-MS and HPLC-UV

    OpenAIRE

    Xiao-Ting Liu; Xu-Guang Wang; Rui Xu; Fan-Hua Meng; Neng-Jiang Yu; Yi-Min Zhao

    2015-01-01

    A high-performance liquid chromatography coupled with quadrupole tandem time-of-flight mass (HPLC-QTOF-MS) and ultraviolet spectrometry (HPLC-UV) was established for simultaneous qualitative and quantitative analysis of the major chemical constituents in Caulis Trachelospermi, respectively. The analysis was performed on an Agilent Zorbax Eclipse Plus C18 column (4.6 mm × 150 mm, 5 μm) using a binary gradient system of water and methanol, with ultraviolet absorption at 230 nm. Based on high-re...

  2. Rapid analysis of components in Rhizoma Anemarrhenae by HPLC-DAD-MS and HPLC-DAD-TOFMS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A global quality control method based on high performance liquid chromatography(HPLC)coupled with diode array detection(DAD),single quadrupole mass spectrometry(MS)and time-of-flight mass spectrometry(TOFMS)was developed for simultaneous determination of seven major components(mangiferin,neomangiferin,timosaponin E1,timosaponin E,timosaponin BⅡ,timosaponin BⅢ,and timosaponin AⅢ)and identification of most components in extracts of Rhizoma Anemarrhenae(RA).HPLC analysis was performed on an Agilent SB-C18 colu...

  3. An Economic Approach to the Self : the Dual Agent

    OpenAIRE

    Lotz, Aïleen

    2011-01-01

    This paper extends the notion of the rational agent in economics by acknowledging the role of the unconscious in the agent�s decision-making process. It argues that the unconscious can be modelled by a rational agent with his own objective function and set of information. The combination of both the conscious and unconscious agents is called the "dual agent". This dual agent presents rationally biased behaviors that may not disappear through aggregation, and could be potentially measured. It ...

  4. Differentiation of tannin-containing herbal drugs by HPLC fingerprints.

    Science.gov (United States)

    He, Yu; Wu, Qiaofeng; Hansen, S H; Cornett, C; Møller, C; Lai, Pingfan

    2013-03-01

    A new HPLC system coupled with multiple detectors - Diode array detector (DAD), fluorescence detector (FLD), electrochemical amperometric detector (ADC) and mass spectrometry detector (MSD) was developed for the characterization and differentiation of tannin-containing herbal drugs included in The European Pharmacopoeia. The HPLC separation system consisted of an Agilent ZORBAX Eclipse XDB C18 column and a gradient water and methanol as the mobile phase which was kept at a flow rate of 0.3 mL x min(-1). Four kinds of detectors were connected by a micro-splitter valve and simultaneously recorded the response of each analytical sample. Thirty-one samples from eight kinds of tannin-containing drugs were measured using this HPLC system and their signals from all detectors were comprehensively processed via principal component analysis (PCA). The statistic result demonstrates that thirty-one batches from different herbal drugs can be reasonably identified and systematically classified by their chemical fingerprints. The proposed multi-detector HPLC method aided by chemometrics not only offers a new pattern for the study of tannin-containing herbs, but also provides a useful foundation for quality control of herbal medicines. PMID:23556331

  5. Efficient post HPLC column generation of arsanes for speciation analysis

    Czech Academy of Sciences Publication Activity Database

    Marschner, Karel; Musil, Stanislav; Rychlovský, P.; Dědina, Jiří

    2015. s. 69-70. [Colloquium Spectroscopicum Internationale /39./. 30.08.2015-03.09.2015, Figueira da Foz] R&D Projects: GA ČR GA14-23532S Grant ostatní: GA AV ČR(CZ) M200311202 Institutional support: RVO:68081715 Keywords : arsenic speciation analysis * hydride generation * HPLC Subject RIV: CB - Analytical Chemistry, Separation

  6. Separation of complex oligosaccharides from wort and beer using HPLC

    Czech Academy of Sciences Publication Activity Database

    Cabálková, Jana; Bobálová, Janette

    2008-01-01

    Roč. 102, č. 15 (2008), s608-s609. ISSN 1803-2389. [Meeting on Chemistry and Life /4./. Brno, 09.09.2008-11.09.2008] R&D Projects: GA MŠk 2B06037 Institutional research plan: CEZ:AV0Z40310501 Keywords : oligosacharides * beer * HPLC Subject RIV: CB - Analytical Chemistry , Separation

  7. HPLC ANALYSIS OF VINCLOZOLIN AND ITS METABOLITES IN SERUM

    Science.gov (United States)

    HPLC ANALYSIS OF VINCLOZOLIN AND ITS METABOLITES IN SERUM. A Sierra-Santoyo1,2, H A Barton1 and M F Hughes1. 1US EPA, ORD, NHEERL, ETD, RTP, NC; 2Toxicology Section, CINVESTAV-IPN, Mexico City, Mexico. The fungicide vinclozolin (V) is used predominantly for treatment...

  8. Determination of Biogenic Amines with HPLC-APCI-MS

    Science.gov (United States)

    Determination of biogenic amines in fish samples can be used as a quality attribute and are commonly performed using a derivatization step followed by high pressure liquid chromatography (HPLC) and UV detection. Over estimation and misidentification of biogenic amines can occur when interfering comp...

  9. Intelligent agent support for automated radiology exam

    Science.gov (United States)

    Shang, Yi; Popescu, Mihail

    2000-10-01

    A difficult problem in automatic medical image understanding is that for every image type such as x-ray and every body organ such as heart, there exist specific solutions that do not allow for generalization. Just collecting all the specific solutions will not achieve the vision of a computerized physician. To address this problem, we propose an intelligent agent approach that is based on agent-oriented programming is that it combines the benefits of object-oriented programming and expert system. For radiology image understanding, we present a multi- agent system that is composed of two major types of intelligent agents: radiologist agents and patient agents. A patient agent asks for multiple opinions from radiologists agents in interpreting a given set of images and then integrates the opinions. A radiologist agent decomposes the image recognition task into smaller problems that are solved collectively by multiple intelligent sub-agents. Finally, we present a preliminary implementation and running examples of the multi-agent system.

  10. High performance thin layer chromatography (HPTLC) and high performance liquid chromatography (HPLC) for the qualitative and quantitative analysis of Calendula officinalis-advantages and limitations.

    Science.gov (United States)

    Loescher, Christine M; Morton, David W; Razic, Slavica; Agatonovic-Kustrin, Snezana

    2014-09-01

    Chromatography techniques such as HPTLC and HPLC are commonly used to produce a chemical fingerprint of a plant to allow identification and quantify the main constituents within the plant. The aims of this study were to compare HPTLC and HPLC, for qualitative and quantitative analysis of the major constituents of Calendula officinalis and to investigate the effect of different extraction techniques on the C. officinalis extract composition from different parts of the plant. The results found HPTLC to be effective for qualitative analysis, however, HPLC was found to be more accurate for quantitative analysis. A combination of the two methods may be useful in a quality control setting as it would allow rapid qualitative analysis of herbal material while maintaining accurate quantification of extract composition. PMID:24880991

  11. Control de pigmentos clorofílicos y carotenoides por HPLC en el aceite de oliva virgen

    Directory of Open Access Journals (Sweden)

    Gandul Rojas, B.

    1991-02-01

    Full Text Available The use of solid phase extraction columns of octadecyl (C18 to get a fat free pigment extract in combination with reversed phase ion pair HPLC permits the separation of chlorophylls and its derivates, carotenoids, xantophylis and metalochlorophyllic complexes in a maximum period of one hour.

    El uso de columnas de extracción en fase sólida (EFS de octadecyl (C18 para obtener un extracto de pigmentos exento de materia grasa en combinación con la HPLC en fase reversa de pares iónicos, permite la separación de clorofilas y derivados, carotenos, xantofilas y complejos metaloclorofílicos en un tiempo máximo de una hora.

  12. HPLC-DAD-ESI-MS analysis of phenolic compounds during ripening in exocarp and mesocarp of tomato fruit.

    Science.gov (United States)

    Carrillo-López, Armando; Yahia, Elhadi

    2013-12-01

    Identification of phenolic compounds was done by means of liquid chromatography (HPLC) coupled to mass spectrometry (MS) using the electrospray ionization interface (ESI). Quantification of phenolic compounds was carried out by using HPLC with diode array detector (DAD) in exocarp and mesocarp of tomato fruit at 6 different ripeness stages (mature-green, breakers, turning, pink, light-red, and red). Several phenolic compounds were identified including chlorogenic acid, caffeic acid, p-coumaric acid, ferulic acid, and rutin and some combined phenolic acids were tentatively identified, mainly glycosides, such as caffeoyl hexose I, caffeoyl hexose II, caffeoylquinic acid isomer, dicaffeoylquinic acid, p-coumaroyl hexose I, p-coumaroyl hexose II, feruloyl hexose I, feruloyl hexose II, siringyl hexose, and caffeoyl deoxyhexose hexose. Fruit exocarp had higher quantities of total soluble phenolics (TSP) compared to mesocarp. During ripening, TSP increased in both exocarp and mesocarp, mainly in exocarp. While rutin increased, chlorogenic acid decreased in both tissues: exocarp and mesocarp. PMID:24171765

  13. Analysis of taxines in Taxus plant material and cell cultures by hplc photodiode array and hplc-electrospray mass spectrometry

    NARCIS (Netherlands)

    Theodoridis, G.; Laskaris, G.; Rozendaal, E.L.M.; Verpoorte, R.

    2001-01-01

    A semi-purified Taxus baccata needles extract was analysed by RP-HPLC. More than 18 taxines and cinnamates were detected by photodiode array detection and LC-MS, 10 of them being positively identified. Furthermore, 10-deacetyl baccatin III (paclitaxel's main precursor) and other taxanes were also fo

  14. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS

    Directory of Open Access Journals (Sweden)

    Maria Tasioula-Margari

    2015-08-01

    Full Text Available The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO, from different Greek olive varieties. Sufficient recoveries (90% of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected.

  15. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS.

    Science.gov (United States)

    Tasioula-Margari, Maria; Tsabolatidou, Eleftheria

    2015-01-01

    The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected. PMID:26783843

  16. Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

    Science.gov (United States)

    Analytical methods for selenium (Se) speciation were developed using high performance liquid chromatography (HPLC) coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionization tandem mass spectrometry (ESI-MS/MS). Separations of selenomethionine (Se-Met) and sel...

  17. In vitro antibacterial activity of fosfomycin combined with nine antimicrobial agents against acinetobacter%磷霉素与9种抗菌药物分别联用对不动杆菌的体外抗菌活性研究

    Institute of Scientific and Technical Information of China (English)

    杨莹莹; 王镇山; 薛欣; 聂大平; 李玉中

    2011-01-01

    [ Objective] To study the antibacterial activity of fosfomycin combined with other 9 antimicrobial agents against 47 strains of Acinetobacter in vitro, in order to provide laboratory data for clinical combination application. [ Methods] The 47 strains of acinetobacter isolated from sputum samples were treated by 10 antimicrobial agents alone and by fosfomycin combined with other 9 antimicrobial agents. Through the minimal inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) index, using a two -fold agar dilution method, we could evaluate the antibacterial activity of fosfomycin combined with other 9 antimicrobial agents in vitro. [ Results] All the 47 strains of acinetobacter were resistant to fosfomycin, levofloxacin, ciprofloxacin, cefuroxime, ceftazidime, cefepime, cefoperazone/sulbactam, amikacin, and were intermedium to meropenem and imipenem/cilastatin. The ratio of antimicrobial agents was 1: 1. The MICs of fosfomycin combined with other 9 antimicrobial agents were lower than those of 10 antimicrobial agents alone and FIC index≤2. The primary action was synergistic/additional effect. There was no antagonistic effect observed. [ Conclusion] Synergistic/additional effect was observed in fosfomycin combined with levofloxacin, ciprofioxacin, cefuroxime, ceftazidime, cefepime, cefoperazone/sulbactam, amikacin, meropenem and imipenem/cilastatin against acinetobacter in vitro. The antimicrobial activities of combination were increased.%[目的]研究磷霉素与其它9种临床常用抗菌药物分别联合应用对47株不动杆菌的体外抗菌活性.[方法]收集痰标本中分离出的不动杆菌47株,将磷霉素与其它9种抗菌药物在体外单独以及联合应用,采用琼脂二倍稀释法,测定最低抑菌浓度(MIC)、计算部分抑菌浓度(FIC)指数,评价磷霉素与其它9种抗菌药物分别联合应用的体外抗菌活性.[结果]磷霉素、左氧氟沙星、环丙沙星、头孢呋辛、头孢他啶、头孢

  18. Application of directly coupled HPLC MMR to separation and characterization of lipoproteins from human serum

    DEFF Research Database (Denmark)

    Daykin, C. A.; Corcoran, O.; Hansen, S. H.;

    2001-01-01

    plasma proteins such as albumin occurred, and this clearly limits quantitation of that species by HPLC peak integration. We also show, for the first time, the application of directly coupled HPLC H-1 NMR spectroscopy to confirm the identification of the three major lipoproteins, The full chromatographic...... by the HPLC separation and that their gross supramolecular organization was intact....

  19. Vergelijking van HPLC-methoden voor de bepaling van pentachloorfenol in houtmonsters

    NARCIS (Netherlands)

    Goewie; C.E.; Berkhoff; C.J.

    1986-01-01

    Een vergelijkend onderzoek is verricht naar de bruikbaarheid van verschillende detectiemethoden in combinatie met HPLC voor de analyse van pentachloorfenol in hout. In het onderzoek wordt RP-HPLC met UK en amperometrische detectie beschreven, evenals NP-HPLC met elektroneninvangdetectie. In vers

  20. VERIFICATION HPLC METHOD OF QUANTITATIVE DETERMINATION OF AMLODIPINE IN TABLETS

    Directory of Open Access Journals (Sweden)

    Khanin V. A

    2014-10-01

    Full Text Available Introduction. Amlodipine ((±-2-[(2-aminoetoksimethyl]-4-(2-chlorophenyl-1,4-dihydro-6-methyl-3,5-pyridine dicarboxylic acid 3-ethyl 5-methyl ester as besylate and small tally belongs to the group of selective long-acting calcium channel blockers, dihydropyridine derivatives. In clinical practice, as antianginal and antihypertensive agent for the treatment of cardiovascular diseases. It is produced in powder form, substance and finished dosage forms (tablets of 2.5, 5 and 10 mg. The scientific literature describes methods of quantitative determination of the drug by spectrophotometry – by his own light absorption and by reaction product with aloksan, chromatography techniques, kinetic-spectrophotometric method in substances and preparations and methods chromatomass spectrometry and stripping voltammetry. For the quantitative determination of amlodipine besylate British Pharmacopoeia and European Pharmacopoeia recommend the use of liquid chromatography method. In connection with the establishment of the second edition of SPhU and when it is comprised of articles on the finished product, we set out to analyze the characteristics of the validation of chromatographic quantitative determination of amlodipine besylate tablets and to verify the analytical procedure. Material & methods. In conducting research using substance amlodipine besylate series number AB0401013. Analysis subject pill “Amlodipine” series number 20113 manufacturer of “Pharmaceutical company “Zdorovye”. Analytical equipment used is: 2695 chromatograph with diode array detector 2996 firms Waters Corp. USA using column Nova-Pak C18 300 x 3,9 mm with a particle size of 4 μm, weight ER-182 company AND Japan, measuring vessel class A. Preparation of the test solution. To accurately sample powder tablets equivalent to 50 mg amlodipine, add 30 ml of methanol, shake for 30 minutes, dilute the solution to 50.0 ml with methanol and filtered. 5 ml of methanol solution adjusted to

  1. HPLC Analysis, Optimization of Extraction Conditions and Biological Evaluation of Corylopsis coreana Uyeki Flos

    Directory of Open Access Journals (Sweden)

    Ji-Hye Seo

    2016-01-01

    Full Text Available A method for the separation and quantification of three flavonoids and one isocoumarin by reverse-phase high performance liquid chromatography (HPLC has been developed and validated. Four constituents present in a crude ethanolic extract of the flowers of Coryloposis coreana Uyeki, were analyzed. Bergenin, quercetin, quercitrin and isosalipurposide were used as calibration standards. In the present study, an excellent linearity was obtained with an r2 higher than 0.999. The chromatographic peaks showed good resolution. In combination with other validation data, including precision, specificity, and accuracy, this method demonstrated good reliability and sensitivity, and can be conveniently used for the quantification of bergenin, quercetin, quercitrin and isosalipurposide in the crude ethanolic extract of C. coreana Uyeki flos. Furthermore, the plant extracts were analyzed with HPLC to determine the four constituents and compositional differences in the extracts obtained under different extraction conditions. Several extracts of them which was dependent on the ethanol percentage of solvent were also analyzed for their antimicrobial and antioxidant activities. One hundred % ethanolic extract from C. coreana Uyeki flos showed the best antimicrobial activity against the methicillin-resistant Staphylococcus aureus (MRSA strain. Eighty % ethanolic extract showed the best antioxidant activity and phenolic content. Taken of all, these results suggest that the flower of C. coreana Uyeki flos may be a useful source for the cure and/or prevention of septic arthritis, and the validated method was useful for the quality control of C. coreana Uyeki.

  2. A global seasonal surface ocean climatology of phytoplankton types based on CHEMTAX analysis of HPLC pigments

    Science.gov (United States)

    Swan, Chantal M.; Vogt, Meike; Gruber, Nicolas; Laufkoetter, Charlotte

    2016-03-01

    Much advancement has been made in recent years in field data assimilation, remote sensing and ecosystem modeling, yet our global view of phytoplankton biogeography beyond chlorophyll biomass is still a cursory taxonomic picture with vast areas of the open ocean requiring field validations. High performance liquid chromatography (HPLC) pigment data combined with inverse methods offer an advantage over many other phytoplankton quantification measures by way of providing an immediate perspective of the whole phytoplankton community in a sample as a function of chlorophyll biomass. Historically, such chemotaxonomic analysis has been conducted mainly at local spatial and temporal scales in the ocean. Here, we apply a widely tested inverse approach, CHEMTAX, to a global climatology of pigment observations from HPLC. This study marks the first systematic and objective global application of CHEMTAX, yielding a seasonal climatology comprised of ~1500 1°×1° global grid points of the major phytoplankton pigment types in the ocean characterizing cyanobacteria, haptophytes, chlorophytes, cryptophytes, dinoflagellates, and diatoms, with results validated against prior regional studies where possible. Key findings from this new global view of specific phytoplankton abundances from pigments are a) the large global proportion of marine haptophytes (comprising 32±5% of total chlorophyll), whose biogeochemical functional roles are relatively unknown, and b) the contrasting spatial scales of complexity in global community structure that can be explained in part by regional oceanographic conditions. The results are publically accessible via

  3. HPLC Analysis, Optimization of Extraction Conditions and Biological Evaluation of Corylopsis coreana Uyeki Flos.

    Science.gov (United States)

    Seo, Ji-Hye; Kim, Jung-Eun; Shim, Jung-Hyun; Yoon, Goo; Bang, Mi-Ae; Bae, Chun-Sik; Lee, Kyung-Jin; Park, Dae-Hun; Cho, Seung-Sik

    2016-01-01

    A method for the separation and quantification of three flavonoids and one isocoumarin by reverse-phase high performance liquid chromatography (HPLC) has been developed and validated. Four constituents present in a crude ethanolic extract of the flowers of Coryloposis coreana Uyeki, were analyzed. Bergenin, quercetin, quercitrin and isosalipurposide were used as calibration standards. In the present study, an excellent linearity was obtained with an r² higher than 0.999. The chromatographic peaks showed good resolution. In combination with other validation data, including precision, specificity, and accuracy, this method demonstrated good reliability and sensitivity, and can be conveniently used for the quantification of bergenin, quercetin, quercitrin and isosalipurposide in the crude ethanolic extract of C. coreana Uyeki flos. Furthermore, the plant extracts were analyzed with HPLC to determine the four constituents and compositional differences in the extracts obtained under different extraction conditions. Several extracts of them which was dependent on the ethanol percentage of solvent were also analyzed for their antimicrobial and antioxidant activities. One hundred % ethanolic extract from C. coreana Uyeki flos showed the best antimicrobial activity against the methicillin-resistant Staphylococcus aureus (MRSA) strain. Eighty % ethanolic extract showed the best antioxidant activity and phenolic content. Taken of all, these results suggest that the flower of C. coreana Uyeki flos may be a useful source for the cure and/or prevention of septic arthritis, and the validated method was useful for the quality control of C. coreana Uyeki. PMID:26784157

  4. HPLC-NMR在化学品检测中的应用前景%APPLICATION PROSPECTS OF HPLC-NMR IN CHEMICAL DETECTIONS

    Institute of Scientific and Technical Information of China (English)

    潘瑞花; 陈建华; 张剑锋

    2007-01-01

    简要介绍高效液相色谱-核磁共振(HPLC-NMR)联用技术.综述了目前HPLC-NMR联用技术在药物代谢研究,天然产物分析以及食品分析等方面的应用.展望了HPLC-NMR在化学品分类鉴定中的应用前景.

  5. Combination Chemotherapy for Influenza

    Directory of Open Access Journals (Sweden)

    Robert G. Webster

    2010-07-01

    Full Text Available The emergence of pandemic H1N1 influenza viruses in April 2009 and the continuous evolution of highly pathogenic H5N1 influenza viruses underscore the urgency of novel approaches to chemotherapy for human influenza infection. Anti-influenza drugs are currently limited to the neuraminidase inhibitors (oseltamivir and zanamivir and to M2 ion channel blockers (amantadine and rimantadine, although resistance to the latter class develops rapidly. Potential targets for the development of new anti-influenza agents include the viral polymerase (and endonuclease, the hemagglutinin, and the non-structural protein NS1. The limitations of monotherapy and the emergence of drug-resistant variants make combination chemotherapy the logical therapeutic option. Here we review the experimental data on combination chemotherapy with currently available agents and the development of new agents and therapy targets.

  6. HPLC analysis of methanolic extract of herbs for quercetin content

    Directory of Open Access Journals (Sweden)

    Nitu Trehan

    2013-05-01

    Full Text Available Herbs are rich source of flavonoids. Flavonoids are polyphenolic compounds that are ubiquitous in nature and are categorized according to their chemical structure, into flavones, isoflavonoes and flavon-3-ol, anthocyanidins. They have aroused considerable interest because of their potential beneficial effect on human health. They have been reported to have antiviral, anti allergic, anti platelet, anti inflammatory, antitumor, anti carcinogenic and anti ageing properties. HPLC analysis can be used for classification of herbs based upon secondary metabolites. Extract yield at optimum condition was then analyzed by high performance liquid chromatography (HPLC for quantifying bioactive flavonoid compounds. It was observed that mint contains the highest concentration of quercetin i.e. about 10.8mg/g.

  7. AgentChess : An Agent Chess Approach

    OpenAIRE

    Fransson, Henric

    2003-01-01

    The game of chess has many times been discussed and used for test purpose by science departments of Artificial Intelligence (AI). Although the technique of agent and as well multi-agent systems is quite old, the use of these offspring of AI within chess is limited. This report describes the project performed applying the use of agents to a chess program. To measure the performance of the logic has tests between the developed program main parts been performed. Further tests against a tradition...

  8. HPLC-DAD determination of imidacloprid in onion

    OpenAIRE

    Mandić Aljoša; Lazić Sanja; Inđić Dušanka

    2003-01-01

    Imidacloprid is an insecticide most commonly used on vegetables, potato sugar beet, fruit, cereal, maize and rice. Imidacloprid residue has been determined in spiked onion and in onion samples. Sample preparation consisted of dichlormethane extraction of imidacloprid from onion, followed by purification of the obtained extract on a LC-Florisil disposable cartridge. The HPLC-DAD method bas been developed on reversed-phase for separation of imidacloprid with a mixture of 0.01 M phosphate buffer...

  9. Chromatographic Properties of Silica-Based Monolithic HPLC Columns

    OpenAIRE

    Smith, Jennifer Houston

    2002-01-01

    Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of porous silica. The main advantage of such a network is decreased backpressure due to macropores (2 μm) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The Chromolith SpeedROD⠢ (EM Science, Gibbstown NJ) is a commercia...

  10. Determination of sugars in royal jelly by HPLC

    OpenAIRE

    Sesta, Giulio

    2006-01-01

    A HPLC method with refractive index detection (RID) was developed for sugar determination in royal jelly (RJ). The method enables the determination of the three main sugars of royal jelly (fructose, glucose and sucrose), and maltose, which is sometimes present in RJ. The method ensures adequate sensitivity, quantitative recoveries, does not suffer from matrix interferences and shows good repeatability. It was used for the analysis of 97 RJ samples of different origin and the results were foun...

  11. Gradient Scouting in Reversed-Phase HPLC Revisited

    Science.gov (United States)

    Alcazar, A.; Jurado, J. M.; Gonzalez, A. G.

    2011-01-01

    Gradient scouting is the best way to decide the most suitable elution mode in reversed-phase high-performance liquid chromatography (RP-HPLC). A simple rule for this decision involves the evaluation of the ratio [delta]t/t[subscript G] (where [delta]t is the difference in the retention time between the last and the first peak and t[subscript G] is…

  12. HPLC analysis of methanolic extract of herbs for quercetin content

    OpenAIRE

    Nitu Trehan

    2013-01-01

    Herbs are rich source of flavonoids. Flavonoids are polyphenolic compounds that are ubiquitous in nature and are categorized according to their chemical structure, into flavones, isoflavonoes and flavon-3-ol, anthocyanidins. They have aroused considerable interest because of their potential beneficial effect on human health. They have been reported to have antiviral, anti allergic, anti platelet, anti inflammatory, antitumor, anti carcinogenic and anti ageing properties. HPLC analysis can be ...

  13. Agents in domestic environments

    OpenAIRE

    van Moergestel, Leo; Langerak, Wouter; Meerstra, Glenn; Nieuwenburg, Niels van; Pape, Franc; Telgen, Daniël; Puik, Erik; meyer, john-jules

    2013-01-01

    Athor supplied : "This paper describes an agent-based architecture for domotics. This architecture is based on requirements about expandability and hardware independence. The heart of the system is a multi-agent system. This system is distributed over several platforms to open the possibility to tie the agents directly to the actuators, sensors and devices involved. This way a level of abstraction is created and all intelligence of the system as a whole is related to the agents involved. A pr...

  14. HPLC analysis of closed, open, and reflex eye tear proteins

    Directory of Open Access Journals (Sweden)

    Sitaramamma T

    1998-01-01

    Full Text Available Changes in the closed, open and reflex eye tear proteins of normal subjects were compared and analysed. Tear proteins were resolved by high-performance liquid chromatography (HPLC utilising both gel filtration (P-300 SW and reverse-phase (C-18 columns and the HPLC fractions were further analysed by sodium dodecyl sulphate - polyacrylamide gel electrophoresis (SDS-PAGE under reducing and non-reducing conditions. The protein composition of the closed-eye tear was significantly different from that of the open and reflex-eye tear. Secretory IgA (sIgA was the predominant protein in closed eye tears constituting 49% of the total protein compared to 11% in reflex tears, whereas lysozyme was the predominant protein (53% in reflex tears. Levels of lactoferrin, lipocalin and lysozyme were relatively constant in both open and reflex tears. HPLC profiles of the closed-eye tears, upon continuous stimulation of lacrimal glands indicated that sIgA was significantly reduced whereas lactoferrin, lipocalin, and lysozyme were significantly increased. These results indicate that the tear composition upon waking attains that of the open eye within 4 to 5 minutes, and upon continuous stimulation this reflects the reflex-eye tear composition. It also indicates that mechanisms responsible for changes in concentration of constitutive and regulated tear protein with stimulus can be studied successfully using non-invasive methods to collect human tears.

  15. Testing of radiopharmaceuticals by HPLC: continuation and end

    International Nuclear Information System (INIS)

    We presented last year a new testing technique of radiochemical purity by HPLC applicable in numerous radiopharmaceuticals. But, it was not efficient for usual tracers such as the HMDP or DTPA. We have developed a new method for these molecules. As materials we made use of: - the HPLC Waters system equipped with the code Millenium; - the U.V.Waters 486 detector set to 300 nm; - the Flow count-Bioscan (Wallac) radioactivity detector; - the column Waters Nova-pak, C18 60A 4μm, 3.9 x 150 mm. Concerning the method, we made use of gradient separation method as follows: for 0→3 min: 100% butanol-1, 0.7 ml/min; for 3→ 17 min: passage by 100% water by linear gradient; and for 7 → 15 min: gradual flow-rate augmentation to 2 ml/min. We obtained for the retention time (RT) of pertechnetate the value 2 min. This method allows separating the HMDP, the Phytate, the DTPA and the DMSA which present an identical RT of 10.5 min. The hydrolyzed and reduced Tc was not made evident. In conclusion, due to its facility, rapidity and low cost this methodology may be used on a routine base to test the radiochemical purity of these four tracers in a service equipped by a HPLC

  16. Quality evaluation of Perillae Folium by HPLC/PDA.

    Science.gov (United States)

    Zhao, Bing Tian; Lee, Kang Ro; Lee, Je Hyun; Min, Byung Sun; Son, Jong Keun; Woo, Mi Hee

    2015-08-01

    To establish a standard of quality control for Perillae Folium (Lamiaceae Family), four standard compounds including rosmarinic acid, elemicin, perillaldehyde, and dillapiole were evaluated by high-performance liquid chromatography (HPLC)/photodiode array (PDA). The four standards were analyzed with a Phenomenex Kinetex C18 (250 × 4.6 mm, 5 μm) column by gradient elution using 0.1 % formic acid in water and methanol as the mobile phase. The standards were quantified by HPLC/PDA from Perillae Folium, which included the leaf and twig of Perilla frutescens L. Britton var. acuta (Thunb.) Kudo or Perilla frutescens Britton var. crispa Decne. The method was successfully used in the analysis of Perillae Folium, and the linearity, recovery, precision, accuracy, stability, and robustness were satisfactory according to the validation results. In Perillae Folium samples, the average contents (wt%) of rosmarinic acid, elemicin, perillaldehyde, and dillapiole were 0.540, 0.059, 0.050, and 0.056 %, respectively. The results indicate that the established HPLC/PDA method is suitable for the quantitation and quality evaluation of Perillae Folium. PMID:25716430

  17. Extraction and Purification of Depigmenting Agents from Chinese Plants

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Depigmenting agents were solvent-extracted and purified by preparative and analytical HPLC from three Chinese plants; Chrysanthemum morifolium Ramat( Xizang Caijuhua), Rhodiola sachalinensis, and Terminalia chebula Retzius. Four fractions obtained from the ethyl ether layer of C. m. Rama and two fractions from the ethyl acetate layer of Rhodiola salientness show depigmenting effects. At δ 200, the ethyl acetate layers of Chrysanthemum morifolium Ramat, Rhodiola sachalinensis and the methanol extract of Terminalia chebula Retzius, can inhibit the melanin production of mouse B16 melanoma cells by 92%, 60% and 90%, respectively, whereas 46% inhibition was observed by commercially available depigmenting agents(arbutin). These results show the potential of these three Chinese plants as a novel resource for depigmenting agents in the cosmetic industry.

  18. An Interactive Tool for Creating Multi-Agent Systems and Interactive Agent-based Games

    DEFF Research Database (Denmark)

    Lund, Henrik Hautop; Pagliarini, Luigi

    2011-01-01

    Utilizing principles from parallel and distributed processing combined with inspiration from modular robotics, we developed the modular interactive tiles. As an educational tool, the modular interactive tiles facilitate the learning of multi-agent systems and interactive agent-based games. The...

  19. A Plan Fusion Algorithm for Multi-Agent Systems

    NARCIS (Netherlands)

    De Weerdt, M.M.; Bos, A.; Tonino, J.F.M.; Witteveen, C.

    2000-01-01

    We introduce an algorithm for cooperative planning in multi-agent systems. The algorithm enables the agents to combine (fuse) their plans in order to increase their joint profits. A computational resources and skills framework is developed for representing the planned activities of an agent under ti

  20. Culturally Aware Agent Communication

    DEFF Research Database (Denmark)

    Rehm, Matthias; Nakano, Yukiko; Koda, Tomoko;

    2012-01-01

    Agent based interaction in the form of Embodied Conversational Agents (ECAs) has matured over the last decade and agents have become more and more sophisticated in terms of their verbal and nonverbal behavior like facial expressions or gestures. Having such “natural” communication channels...

  1. Riot Control Agents

    Science.gov (United States)

    ... a person has been exposed to riot control agents. Long-term health effects of exposure to riot control agents Prolonged ... person is removed from exposure to riot control agents, long-term health effects are unlikely to occur. How you can ...

  2. Reasoning about emotional agents

    NARCIS (Netherlands)

    Meyer, J.-J.

    2008-01-01

    In this paper we discuss the role of emotions in artificial agent design, and the use of logic in reasoning about the emotional or affective states an agent can reside in. We do so by extending the KARO framework for reasoning about rational agents appropriately. In particular we formalize in this f

  3. Evaluation of mixture effects in a crude extract of compost using the CALUX bioassay and HPLC fractionation

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, G.; Takigami, H.; Sakai, S.I. [National Inst. for Environmental Studies, Yatabe, Ibaraki (Japan). Research Center for Material Cycles and Waste Management; Kushi, Y. [Obihiro Univ. of Agriculture and Veternary Medicine (Japan). Dept. of Bioresource Science

    2004-09-15

    In general, crude extracts and polyaromatic hydrocarbon (PAC)-containing fractions of environmental samples show high activities in the AHR-based bioassay. Although many studies have tried to determine which compounds contribute to this activity based on additivity theory, these values are higher than the corresponding chemically calculated IEQs or TEQ values. These compounds in environmental samples exist as mixtures, and interactions between compounds must be considered in chemical risk assessments. In particular, if synergistic interactions occur in environmental samples, application of the additivity assessment would underestimate real chemical risk. In this study, we investigated mixture effects in an extract of an environmental sample. First we established a simple fractionation procedure for the sample, and then we examined the retention characteristics of PACs using RP-HPLC on an octadecylsilica (ODS) column. Then we applied HPLC fractionation and combined CALUX (DR-CALUX {sup registered}: Dioxin-Responsive Chemical- Activated Luciferase gene expression)/chemical analysis to a night soil sludge (NSS) compost extract to determine which compounds contributed to the CALUX-TEQ (2,3,7,8-TCDD equivalent) of the crude extract. Finally, to assess the mixture effects, we exposed the HPLC fractions to CALUX cells in the presence of 2,3,7,8-TCDD at concentration levels similar to those in the original compost sample and determined whether there was a synergistic interaction between the sample fraction and 2,3,7,8-TCDD in terms of CALUX activity.

  4. Quality evaluation and pattern recognition analyses of marker compounds from five medicinal drugs of Rutaceae family by HPLC/PDA.

    Science.gov (United States)

    Zhao, Bing Tian; Kim, Eun Jung; Son, Kun Ho; Son, Jong Keun; Min, Byung Sun; Woo, Mi Hee

    2015-08-01

    To establish a standard of quality control and to identify different origins for the Rutaceae family [Citri Unshiu Peel (CU), Citri Unshiu Immature Peel (CI), Ponciri Immature Fructus (PI), Aurantii Immature Fructus (AI), and Aurantii Fructus (AU)], 13 standards including rutin (1), narirutin (2), naringin (3), hesperidin (4), neohesperidin (5), neoponcirin (6), poncirin (7), naringenin (8), isosinensetin (9), sinensetin (10), nobiletin (11), heptamethoxyflavone (12), and tangeretin (13) were determined by high performance liquid chromatography (HPLC)/photo-diode array (PDA) analysis. A YMC ODS C18 (250 × 4.6 mm, 5 µm) column was used and the ratio of mobile phases of water (A) and acetonitrile (B) delivered to the column for gradient elution was applied. This method was fully validated with respect to linearity, accuracy, precision, stability, and robustness. The HPLC/PDA method was applied successfully to quantify 13 major compounds in the extracts of CU, CI, PI, AI, and AU. The pattern recognition analysis combined with LC chromatographic data was performed by repeated analysis of 27 reference samples in the above five Rutaceae oriental medicinal drugs. The established HPLC method was rapid and reliable for quantitative analysis and quality control of multiple components in five Rutaceae species with different origins. PMID:25732613

  5. Method development and validation for the analysis of a new anti-cancer infusion solution via HPLC.

    Science.gov (United States)

    Donnarumma, Fabrizio; Schober, Margot; Greilberger, Joachim; Matzi, Veronika; Lindenmann, Jörg; Maier, Alfred; Herwig, Ralf; Wintersteiger, Reinhold

    2011-01-01

    A fast and simple HPLC method has been developed and validated for the quantification of a completely new anti-cancer drug during the manufacturing process. The combination of four compounds including α-ketoglutaric acid, hydroxymethylfurfural, N-acetyl-L-methionine and N-acetyl-L-selenomethionine, administered intravenously, is still in test phase but has already shown promising results in cancer therapy. HPLC separation was achieved on an RP-18 column with a gradient system. However, the highly different concentrations of the compounds required a variation in the detection wavelength within one run. In order to produce a chromatogram where peaks were comparable on a similar range scale, detection at absorption maxima for the two most concentrated components was avoided. After optimization of the gradient program it was possible to detect all four substances within 14 min in spite of their strongly different chemical structure. The method developed was validated for accuracy, repeatability, reproducibility and robustness in relation to temperature and pH of buffer. Linearity as well as the limit of detection and quantification were determined. This HPLC method was found to be precise, accurate and reproducible and can be easily used for in-line process control during the manufacture of the anti-tumour infusion solution. PMID:21246718

  6. Agents modeling agents in information economies

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, J.M.; Durfee, E.H. [Univ. of Michigan, Ann Arbor, MI (United States)

    1996-12-31

    Our goal is to design and build agents that act intelligently when placed in an agent-based information economy, where agents buy and sell services (e.g. thesaurus, search, task planning services, etc.). The economy we are working in is the University of Michigan Digital Library (UMDL), a large scale multidisciplinary effort to build an infrastructure for the delivery of library services. In contrast with a typical economy, an information economy deals in goods and services that are often derived from unique sources (authors, analysts, etc.), so that many goods and services are not interchangeable. Also, the cost of replicating and transporting goods is usually negligible, and the quality of goods and services is difficult to measure objectively: even two sources with essentially the same information might appeal to different audiences. Thus, each agent has its own assessment of the quality of goods and services delivered.

  7. Identification and evaluation of radiolysis products of irradiated chloramphenicol by HPLC-MS and HPLC-DAD

    International Nuclear Information System (INIS)

    The radiolysis products of chloramphenicol under γ-radiation sterilization were investigated systematically in the present study. Eight main radiolysis products were identified and quantified by HPLC-MS and HPLC-DAD, including two compounds that have never been reported. The minor radiolysis products were quantified, which shows that they are at the concentration levels below the threshold for identification. Carbon-carbon rupture reaction and oxidation reaction were proposed as the main radiolysis reactions of chloramphenicol powder. The applicability of γ-sterilization for chloramphenicol products was quantitatively evaluated with qualitative and quantitative data and the data were compared to the threshold requirements of international regulations for identification. It was concluded that toxicities of the radiolysis products of chloramphenicol produced by γ-radiation sterilization can be neglected, the radiolysis products are safe for human health from chemical view. (author)

  8. Qualitative and quantitative analysis of chemical constituents of Centipeda minima by HPLC-QTOF-MS & HPLC-DAD.

    Science.gov (United States)

    Chan, Chi-On; Jin, Deng-Ping; Dong, Nai-Ping; Chen, Si-Bao; Mok, Daniel Kam Wah

    2016-06-01

    A high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) method in both positive and negative ion modes was established to investigate the major constituents in the ethanolic extract of Centipeda minima (EBSC). Twelve common components including flavones and their glycosides, phenolic and polyphenolic acids, and sesquiterpene lactone were identified in ten batches of samples based on comparison with the retention time and accurate mass of external standards (mass accuracy within 3ppm) or the fragmentation patterns of tandem MS. Meanwhile, a simple, accurate and reliable HPLC-DAD method was also developed to determine the content of 10 chemical markers simultaneously. Results obtained from method validations including linearity, accuracy and precision showed that this new method is reliable and robust. Isochlorogenic acid A and brevilin A were found to be the most abundant in the ethanol extract of EBSC and could be served as markers for quality control of EBSC. PMID:27131150

  9. A RP-HPLC method for simultaneous estimation of paracetamol and aceclofenac in tablets

    Directory of Open Access Journals (Sweden)

    Gopinath R

    2007-01-01

    Full Text Available A simple, selective, rapid, precise and economical reverse phase HPLC method has been developed for the simultaneous estimation of paracetamol and aceclofenac from pharmaceutical dosage forms. The method was carried out on a Hichrom C18 (25 cmx4.6 mm i.d., 5 µ column with a mobile phase consisting of acetonitrile:20 mM phosphate buffer (pH 5.0 (60:40 v/v at a flow rate of 0.8 ml/min. Detection was carried out at 265 nm. Etoricoxib was used as an internal standard. The retention time of paracetamol, aceclofenac and etoricoxib was 4.75, 6.44 and 8.83 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantitation and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms.

  10. Determination of lead, cadmium, and mercury by on-line enrichment followed by RP-HPLC

    International Nuclear Information System (INIS)

    A new method for the simultaneous determination of lead, cadmium, and mercury ions as metal tetra-(4-chlorophenyl)-porphyrin (T4CPP) chelates was developed using reversed-phase-high performance liquid chromatography (RP-HPLC) and combined with on-line enrichment technique. The linearity ranges are 0.01 - 120 μg/L for each metal chelate. The detection limits (S/N = 3) of lead, cadmium, and mercury are 2.0 ng/L, 1.5 ng/L, and 2.0 ng/L, respectively. This method was applied to the determination of the μg/L level of lead, cadmium, and mercury ions in a water sample with good results

  11. Size-exclusion HPLC provides a simple, rapid, and versatile alternative method for quality control of vaccines by characterizing the assembly of antigens.

    Science.gov (United States)

    Yang, Yanli; Li, Hao; Li, Zhengjun; Zhang, Yan; Zhang, Songping; Chen, Yi; Yu, Mengran; Ma, Guanghui; Su, Zhiguo

    2015-02-25

    The assembly of antigen structure is often crucial to the potency of vaccines. Currently adopted methods like animal testing and ultracentrifugation take long time and are difficult to automate for multiple samples. Here we develop a size-exclusion high-performance liquid chromatography (SE-HPLC) method to characterize the assembly of antigen structure during both manufacturing process and storage. Three important vaccine antigens including inactivated foot and mouth disease virus (FMDV), which is a virus vaccine; and two virus-like particles (VLPs) vaccines involving hepatitis B core antigen (HBcAg) VLPs, and hepatitis B surface antigen (HBsAg) VLPs, were successfully analyzed using commercially available TSK gel columns with pore size above 45nm. Combined with other analytical methods including SDS-PAGE, dynamic light scattering, wavelength scan, and multi-angle laser light scattering, the SE-HPLC method was proven to be a simple, rapid, and reliable tool for antigen particles assembly analysis. Specifically, for FMDV whole virus particle, SE-HPLC was used to analyze 146S content in vaccine preparations and the thermal dissociation of the 146S. For HBcAg-VLPs that are expressed in recombinant Escherichia coli, its expression level during cell culture process was quantitatively monitored by SE-HPLC. The SE-HPLC also showed applicability for quality check of HBsAg vaccine preparations by monitoring the product consistency of different lot number and the product stability during storage. Results shown in this work clearly demonstrated that SE-HPLC method has potential as a versatile alternative technology for control of the final product by both manufacturers and the regulatory agencies. PMID:25604799

  12. Chemical fingerprinting and quantitative analysis of a Panax notoginseng preparation using HPLC-UV and HPLC-MS

    OpenAIRE

    Shao Qing; Shi Peiying; Yao Hong; Fan Xiaohui

    2011-01-01

    Abstract Background Xuesaitong (XST) injection, consisting of total saponins from Panax notoginseng, was widely used for the treatment of cardio- and cerebro-vascular diseases in China. This study develops a simple and global quality evaluation method for the quality control of XST. Methods High performance liquid chromatography-ultraviolet detection (HPLC-UV) was used to identify and quantify the chromatographic fingerprints of the XST injection. Characteristic common peaks were identified u...

  13. Qualitative and Quantitative Analysis of Lignan Constituents in Caulis Trachelospermi by HPLC-QTOF-MS and HPLC-UV

    Directory of Open Access Journals (Sweden)

    Xiao-Ting Liu

    2015-05-01

    Full Text Available A high-performance liquid chromatography coupled with quadrupole tandem time-of-flight mass (HPLC-QTOF-MS and ultraviolet spectrometry (HPLC-UV was established for simultaneous qualitative and quantitative analysis of the major chemical constituents in Caulis Trachelospermi, respectively. The analysis was performed on an Agilent Zorbax Eclipse Plus C18 column (4.6 mm × 150 mm, 5 μm using a binary gradient system of water and methanol, with ultraviolet absorption at 230 nm. Based on high-resolution ESI-MS/MS fragmentation behaviors of the reference standards, the characteristic cleavage patterns of lignano-9, 9'-lactones and lignano-8'-hydroxy-9, 9'-lactones were obtained. The results demonstrated that the characteristic fragmentation patterns are valuable for identifying and differentiating lignano-9,9'-lactones and lignano-8'-hydroxy-9,9'-lactones. As such, a total of 25 compounds in Caulis Trachelospermi were unambiguously or tentatively identified via comparisons with reference standards or literature. In addition, 14 dibenzylbutyrolatone lignans were simultaneously quantified in Caulis Trachelospermi by HPLC-UV method. The method is suitable for the qualitative and quantitative analyses of dibenzylbutyrolatone lignans in Caulis Trachelospermi.

  14. Quantification of appetite suppressing steroid glycosides from Hoodia gordonii in dried plant material, purified extracts and food products using HPLC-UV and HPLC-MS methods

    NARCIS (Netherlands)

    H.-G. Janssen; C. Swindells; P. Gunning; W. Wang; C. Grün; K. Mahabir; V.J. Maharaj; P.J. Apps

    2008-01-01

    High-performance liquid chromatography (HPLC)-UV and HPLC-Mass Spectrometry (MS) methods were developed for the quantitative analysis of the family of Hoodia gordonii steroid glycosides with appetite suppressing properties in dried plant material, in purified and enriched extracts and in various pro

  15. Combined HPLC analysis of organic acids and furans formed during organosolv pulping of fiber hemp

    NARCIS (Netherlands)

    Gosselink, R.J.A.; Dam, van J.E.G.; Zomers, F.H.A.

    1995-01-01

    During organosolv pulping of fiber hemp (Cannabis sativa L) with a mixture of ethanol/water, delignification is catalyzed by released acetic acid and formic acid in the effluent. The major sources of acetic acid are the acetyl groups, as determined by means of the acetyl balance, whereas formic acid

  16. RP-HPLC determination of atorvastatin calcium and amlodipine besylate combination in tablets

    Directory of Open Access Journals (Sweden)

    Shah D

    2006-01-01

    Full Text Available A simple, specific, accurate and precise reverse-phase high-performance liquid chromatographic method was developed for the simultaneous determination of atorvastatin calcium and amlodipine besylate in tablet dosage forms. A phenomenex Luna C-18, 5 µm column having 250 x 4.6 mm i.d. in isocratic mode, with mobile phase containing methanol: acetonitrile: 50 mM KH 2 PO 4 (20:50:30; pH 3.5 was used. The flow rate was 1.0 ml/min and effluent was monitored at 240 nm. The retention time of atorvastatin calcium and amlodipine besylate was 7.6 min and 3.2 min respectively. The linearity for atorvastatin calcium and amlodipine besylate was in the range of 5-120 µg/ml and 5-100 µg/ml respectively. The proposed method is accurate, precise, specific and rapid for simultaneous estimation of atorvastatin calcium and amlodipine besylate in tablets.

  17. RP-HPLC analysis of aspirin and clopidogrel bisulphate in combination

    Directory of Open Access Journals (Sweden)

    Anandakumar K

    2007-01-01

    Full Text Available A reverse phase high performance liquid chromatography method was developed for the simultaneous estimation of aspirin and clopidogrel bisulphate in formulation. The separation was achieved by octadecyl column (C 18 and acetonitrile:methanol:20 mM phosphate buffer at pH 3 (50:7:43 v/v as eluent, at a flow rate of 1 ml/min. Detection was carried out at 240 nm. Quantitation was done by external standard calibration method. The retention time of aspirin and clopidogrel bisulphate was found to be 2.40 and 9.27 min, respectively. The method has been validated for linearity, accuracy and precision. Linearity for aspirin and clopidogrel bisulphate were in the range of 10-50 µg/ml for both the drugs. The mean recoveries obtained for aspirin and clopidogrel bisulphate were 100.86% and 100.20%, respectively. The developed method was found to be accurate, precise, selective and rapid for the simultaneous estimation of aspirin and clopidogrel bisulphate in capsules.

  18. RP-HPLC estimation of tizanidine HCl and valdecoxib in combined dosage forms

    Directory of Open Access Journals (Sweden)

    Bhavsar A

    2006-01-01

    Full Text Available A reverse phase high performance liquid chromatography method was developed for simultaneous estimation of tizanidine HCl and valdecoxib in tablet formulation. The separation was achieved by Luna C 18 column and acetonitrile: phosphate buffer pH 3.5 (50:50 v/v as eluent, at a flow rate of 0.5 ml/min. Detection was carried out at 227 nm. Etoricoxib was used as an internal standard. The retention time of tizanidine and valdecoxib was found to be 4.43 and 16.60 min, respectively. The method was validated for linearity, accuracy and precision. Linearity for tizanidine and valdecoxib were in the range 0.4-2.0 µg/ml and 4-20 µg/ml, respectively. The developed method was found to be accurate, precise and selective for simultaneous estimation of tizanidine and valdecoxib in tablets.

  19. RP-HPLC estimation of paracetamol and valdecoxib in combined dosage form

    Directory of Open Access Journals (Sweden)

    Bhavsar A

    2006-01-01

    Full Text Available A reverse phase high performance liquid chromatography method was developed for simultaneous estimation of paracetamol and valdecoxib in tablet formulation. The separation was achieved by Luna C 18 column and methanol: phosphate buffer pH 3.5 (60:40 v/v as eluent, at a flow rate of 1.0 ml/min. Detection was carried out at 242 nm. Etoricoxib was used as an internal standard. The retention time of PAR and VAL was found to be 3.01 and 8.51 min, respectively. The method was validated for linearity, accuracy and precision. Linearity for paracetamol and valdecoxib were in the range 25-150 µg/ml and 1-6 µg/ml, respectively. The developed method was found to be accurate, precise, and selective for simultaneous estimation of paracetamol and valdecoxib in tablets.

  20. An Interactive Tool for Creating Multi-Agent Systems and Interactive Agent-based Games

    DEFF Research Database (Denmark)

    Lund, Henrik Hautop; Pagliarini, Luigi

    2011-01-01

    Utilizing principles from parallel and distributed processing combined with inspiration from modular robotics, we developed the modular interactive tiles. As an educational tool, the modular interactive tiles facilitate the learning of multi-agent systems and interactive agent-based games. The...... modular and physical property of the tiles provides students with hands-on experience in exploring the theoretical aspects underlying multi-agent systems which often appear as challenging to students. By changing the representation of the cognitive challenging aspects of multi-agent systems education to a...

  1. A Sensitive and Robust Ultra HPLC Assay with Tandem Mass Spectrometric Detection for the Quantitation of the PARP Inhibitor Olaparib (AZD2281 in Human Plasma for Pharmacokinetic Application

    Directory of Open Access Journals (Sweden)

    Jeffrey Roth

    2014-06-01

    Full Text Available Olaparib (AZD2281 is an orally active PARP-1 inhibitor, primarily effective against cancers with BRCA1/2 mutations. It is currently in Phase III development and has previously been investigated in numerous clinical trials, both as a single agent and in combination with chemotherapy. Despite this widespread testing, there is only one published method that provides assay details and stability studies for olaparib alone. A more sensitive uHPLC-MS/MS method for the quantification of olaparib in human plasma was developed, increasing the range of quantification at both ends (0.5–50,000 ng/mL compared to previously published methods (10–5,000 ng/mL. The wider range encompasses CMAX levels produced by typical olaparib doses and permits better pharmacokinetic modeling of olaparib elimination. This assay also utilizes a shorter analytical runtime, allowing for more rapid quantification and reduced use of reagents. A liquid-liquid extraction was followed by chromatographic separation on a Waters UPLC® BEH C18 column (2.1 × 50 mm, 1.7 µm and mass spectrometric detection. The mass transitions m/z 435.4→281.1 and m/z 443.2→281.1 were used for olaparib and the internal standard [2H8]-olaparib, respectively. The assay proved to be accurate (<9% deviation and precise (CV < 11%. Stability studies showed that olaparib is stable at room temperature for 24 h. in whole blood, at 4 °C for 24 h post-extraction, at −80 °C in plasma for at least 19 months, and through three freeze-thaw cycles. This method proved to be robust for measuring olaparib levels in clinical samples from a Phase I trial.

  2. Evaluation of Synergistic Antibacterial and Antioxidant Efficacy of Essential Oils of Spices and Herbs in Combination

    Science.gov (United States)

    Bag, Anwesa; Chattopadhyay, Rabi Ranjan

    2015-01-01

    as p-coumaric acid (7.14%) by DART-MS and HPLC analyses. The coriander/cumin seed oil combination did not show any cytotoxic effect both in brine shrimp lethality as well as human normal colon cell line assays. The LC50 in brine shrimp lethality assay was found to be 4945.30 μg/ml and IC50 in human normal colon cell line was > 1000 μg/ml. The results provide evidence that coriander/cumin seed oil combination might indeed be used as a potential source of safe and effective natural antimicrobial and antioxidant agents in pharmaceutical and food industries. PMID:26132146

  3. Evaluation of Synergistic Antibacterial and Antioxidant Efficacy of Essential Oils of Spices and Herbs in Combination.

    Directory of Open Access Journals (Sweden)

    Anwesa Bag

    identified as p-coumaric acid (7.14% by DART-MS and HPLC analyses. The coriander/cumin seed oil combination did not show any cytotoxic effect both in brine shrimp lethality as well as human normal colon cell line assays. The LC50 in brine shrimp lethality assay was found to be 4945.30 μg/ml and IC50 in human normal colon cell line was > 1000 μg/ml. The results provide evidence that coriander/cumin seed oil combination might indeed be used as a potential source of safe and effective natural antimicrobial and antioxidant agents in pharmaceutical and food industries.

  4. An Agent-Based Data Mining System for Ontology Evolution

    Science.gov (United States)

    Hadzic, Maja; Dillon, Darshan

    We have developed an evidence-based mental health ontological model that represents mental health in multiple dimensions. The ongoing addition of new mental health knowledge requires a continual update of the Mental Health Ontology. In this paper, we describe how the ontology evolution can be realized using a multi-agent system in combination with data mining algorithms. We use the TICSA methodology to design this multi-agent system which is composed of four different types of agents: Information agent, Data Warehouse agent, Data Mining agents and Ontology agent. We use UML 2.1 sequence diagrams to model the collaborative nature of the agents and a UML 2.1 composite structure diagram to model the structure of individual agents. The Mental Heath Ontology has the potential to underpin various mental health research experiments of a collaborative nature which are greatly needed in times of increasing mental distress and illness.

  5. Studies of dynamics of physical agent ecosystems

    OpenAIRE

    Muñoz Moreno, Israel

    2002-01-01

    This thesis addresses the problem of learning in physical heterogeneous multi-agent systems(MAS) and the analysis of the benefits of using heterogeneous MAS with respect tohomogeneous ones. An algorithm is developed for this task; building on a previous work on stability in distributed systems by Tad Hogg and Bernardo Huberman, and combining two phenomena observed in natural systems, task partition and hierarchical dominance. This algorithm is devised for allowing agents to learn which are th...

  6. Agent-Based Data Integration Framework

    OpenAIRE

    Łukasz Faber

    2014-01-01

    Combining data from diverse, heterogeneous sources while facilitating a unified access to it is an important (albeit difficult) task. There are various possibilities of performing it. In this publication, we propose and describe an agent-based framework dedicated to acquiring and processing distributed, heterogeneous data collected from diverse sources (e.g., the Internet, external software, relational, and document databases). Using this multi-agent-based approach in the aspects of the gener...

  7. Participatory simulation of land-use changes in the northern mountains of Vietnam : the combined use of an agent-base model, a role-playing game, and a geographic information system

    OpenAIRE

    Tran Ngoc Trung; Jean-Christophe Castella; Stanislas Boissau

    2005-01-01

    In Vietnam, the remarkable economic growth that resulted from the doi moi (renovation) reforms was based largely on the rural households that had become the new basic unit of agricultural production in the early 1990s. The technical, economic, and social changes that accompanied the decollectivization process transformed agricultural production, resource management, land use, and the institutions that defined access to resources and their distribution. Combined with the extreme biophysical, t...

  8. Determination of the chemical and radiochemical purity and specific radioactivity of [18F]FDG by HPLC

    International Nuclear Information System (INIS)

    High performance liquid chromatography (HPLC) in combination with the radioactivity detection is the best control method for the radiochemical purity of [18F]FDG. An anion exchange separation mechanism allows isocratic separation of carbohydrates. Using a strong basic eluent, the weakly acid carbohydrates form anions and are therefore retained on the anion exchange resin. The chemical and radiochemical purity and specific radioactivity can be determined simultaneously by including in the chromatographic system a mass detector sensitive, enough for quantitative determination of the product species. (orig.)

  9. Enantioselective semi-preparative HPLC separation of PCB metabolites and their absolute structures determined by electronic and vibrational circular dichroism

    Energy Technology Data Exchange (ETDEWEB)

    Tuan, H.P.; Larsson, C.; Huehnerfuss, H. [Hamburg Univ. (Germany). Inst. fuer Organische Chemie; Hoffmann, F.; Froeba, M. [Giessen Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Bergmann, Aa. [Stockholm Univ. (Sweden). Dept. of Environmental Chemistry

    2004-09-15

    The present paper represents a first result of an ongoing systematic study of atropisomeric methylsulfonyl, methylthionyl, hydroxy, and methoxy metabolites of environmentally most relevant PCBs. This involves semi-preparative enantioselective HPLC separation to obtain pure atropisomers from synthesized PCB metabolite standards, their configuration estimation using the electronic circular dichroism (UV-CD) method and the determination / confirmation of these absolute configurations applying the combined vibrational circular dichroism (VCD) / ab initio approach. The following substances have been investigated: 4-HO-, 4-MeO-, 4-MeS-, 4-MeSO2-, 3-MeS- and 3-MeSO{sub 2}-CB149.

  10. Determination of 10 ginsenosides in Panax ginseng of different harvest times based on HPLC fingerprints and principal component analysis.

    Science.gov (United States)

    Chen, Fengqin; Luo, Jianguang; Kong, Lingyi

    2013-01-01

    A combinative method of HPLC fingerprinting and quantitative determination was successfully applied to monitor dynamic accumulation of ginsenosides in five-year-old Panax ginseng roots from different harvest times. The optimal chromatographic conditions were achieved on a C18 column with gradient elution using acetonitrile and 1 mmol · L(-1) KH2PO4 buffer solution at 203 nm. The result indicated that the contents of total ginsenosides showed significant variations, and a decrease tendency appeared in the growth period of the fifth year. PMID:22871218

  11. Urinary antimony speciation by HPLC-ICP-MS

    OpenAIRE

    Krachler, M; Emons, H

    2001-01-01

    This is the first study to report on the determination of Sb species in urine. To this end, HPLC was coupled online to an ICP-MS instrument using ultrasonic nebulization (USN) or hydride generation (HG) for sample introduction into the ICP-MS. The high chloride concentration in urine seriously hampered the chromatographic separation of Sb(v) and Sb(III) on the Dionex AS14 anion exchange column. Distinct signal suppression, shifting of retention times and severe peak broadening did not allow t...

  12. Enzymatic hydrolysis of whey protein concentrates : peptide HPLC profiles

    OpenAIRE

    Mota, M. V. T.; Ferreira, I. M. P. L. V. O.; Oliveira, M. B. P.; Rocha, Cristina M. R.; J. A. Teixeira; Torres, D; M. P. Gonçalves

    2004-01-01

    Hydrolysis of whey protein concentrates (WPCs) at different temperatures and pHs, using three enzymes: pepsin, trypsin, and Alcalase®, was monitored during more than 5 hr by reversed phase HPLC/UV, using a column containing a polystyrene-divinylbenzene copolymer-based packing, and an elution gradient from 8% to 80% acetonitrile containing 0.1% TFA. Peptides were separated according to their polarity and size, and degradation of α-lactalbumin (α-la) and β-lactoglobulin (β-lg) ...

  13. Determination of selectivity of HPLC systems by correspondence factor analysis

    Institute of Scientific and Technical Information of China (English)

    Yuan Wang; Jun Yang; Xin Lu; Guo Wang Xu

    2007-01-01

    Correspondence factor analysis (CFA) was employed to study the selectivity of 14 HPLC systems, The tested LC systems were classified as reversed-phase (RP), ion-exchange (IE) and hydrophilic interaction chromatography (HILIC) modes. It was found that the retentions of the hydrophilic solutes on HILIC column were significantly influenced by the second-order effects besides their hydrophilic properties. Organic modifiers and residue silanol groups on silica surface both participated in retention. HypersilTM amino column performed separation in the HILIC mode at appropriate conditions, and its retention mechanism was more similar to that of HILIC silica column than that of HILIC column coating poly(aspartamide) groups.

  14. HPLC identification of isoniazid residues in bovine milk

    OpenAIRE

    Leite R.M.H.; Leite R.C.; Lima J.A.; Fóscolo C.B.; Mota P.M.P.C.; Lobato F.C.F.; Lage A.P.

    2000-01-01

    The high pressure liquid chromatography (HPLC) was used for the identification of isoniazid (isonicotinic acid hydrazide) in the milk of cattle treated with a dose of 25 mg/kg/day in alternated days. The effect of milk pasteurization on the isoniazid residue concentration was also studied. The drug excretion presented a cyclic variation, with higher levels in the first day after administration (aa), a mean of 1104.48µg/l, and a decrease two days aa, with a mean of 104.12µg/l. Four days after ...

  15. Determination of doxazosin mesylate in tablets by RP-HPLC

    Directory of Open Access Journals (Sweden)

    B Dhanya

    2011-01-01

    Full Text Available A simple, precise and rapid RP-HPLC method was developed for the determination of doxazosin mesylate in pharmaceutical formulations. The method was carried out on a Chromolith RP-C 18 column using a mixture of potassium phosphate buffer and methanol (40:60 v/v and detection was done at 251 nm. The linearity range was 1-5 μg/ml. The retention time of the drug was 3.8 min. The LOD and LOQ were found to be 0.1 μg/ml and 0.5 μg/ml, respectively.

  16. Determination of carbonyl compounds in air by HPLC

    International Nuclear Information System (INIS)

    A method for the determination of seven carbonyl compounds in air is presented. The procedure involve sampling of air by a Sep-Pak cartridge impregnated with 2,4-dinitrophenylhydrazine. Elution was done with 3 mL of acetonitrile and the eluate was diluted to 5 mL. The analysis was done by HPLC with UV detection and external standard method quantification. It has been achieved relative standard deviations about 5% and detection limits of 80 ng/cartridge for formaldehyde, acetaldehyde and acetone+acrolein. Three different types of samples (rural, urban, petrol emission) were successfully analyzed

  17. Coral Pigments: Quantification Using HPLC and Detection by Remote Sensing

    Science.gov (United States)

    Cottone, Mary C.

    1995-01-01

    Widespread coral bleaching (loss of pigments of symbiotic dinoflagellates), and the corresponding decline in coral reef health worldwide, mandates the monitoring of coral pigmentation. Samples of the corals Porites compressa and P. lobata were collected from a healthy reef at Puako, Hawaii, and chlorophyll (chl) a, peridinin, and Beta-carotene (Beta-car) were quantified using reverse-phase high performance liquid chromatography (HPLC). Detailed procedures are presented for the extraction of the coral pigments in 90% acetone, and the separation, identification, and quantification of the major zooxanthellar pigments using spectrophotometry and a modification of the HPLC system described by Mantoura and Llewellyn (1983). Beta-apo-8-carotenal was found to be inadequate as in internal standard, due to coelution with chl b and/or chl a allomer in the sample extracts. Improvements are suggested, which may result in better resolution of the major pigments and greater accuracy in quantification. Average concentrations of peridinin, chl a, and Beta-car in corals on the reef were 5.01, 8.59, and 0.29, micro-grams/cm(exp 2), respectively. Average concentrations of peridinin and Beta-car did not differ significantly between the two coral species sampled; however, the mean chl a concentration in P. compressa specimens (7.81 ,micro-grams/cm(exp 2) was significantly lower than that in P. lobata specimens (9.96 11g/cm2). Chl a concentrations determined spectrophotometrically were significantly higher than those generated through HPLC, suggesting that spectrophotometry overestimates chl a concentrations. The average ratio of chl a-to-peridinin concentrations was 1.90, with a large (53%) coefficient of variation and a significant difference between the two species sampled. Additional data are needed before conclusions can be drawn regarding average pigment concentrations in healthy corals and the consistency of the chl a/peridinin ratio. The HPLC pigment concentration values

  18. Monitoring method for surface contamination caused by selected antineoplastic agents.

    Science.gov (United States)

    Larson, R R; Khazaeli, M B; Dillon, H Kenneth

    2002-02-01

    A method of evaluating surface contamination caused by selected antineoplastic agents was studied. The antineoplastic agents tested were cyclophosphamide, ifosfamide, doxorubicin hydrochloride, fluorouracil, and paclitaxel. Each agent was reconstituted and prepared as a stock solution. A 0.1-mL portion of each solution was spread evenly over a 600-cm2 area of a stainless steel surface, a resin countertop surface, and a vinyl flooring surface. After drying, the surfaces were wiped with each of two types of commercially available wiping materials (What-man no. 42 filters and Kimberly-Clark Kimwipes). A blend of methanol, acetonitrile, and buffered water was used both as the wetting agent for wiping the surfaces and as a desorbing solution. The desorbate was analyzed for drug concentration by reverse-phase high-performance liquid chromatography (HPLC). Mean +/- S.D. percent total recovery ranged from 72.4% +/- 17.6% to 95.3% +/- 2.9% for the vinyl surface wiped with filters, 91.5% +/- 5.4% to 104.7% +/- 0.8% for the resin surface wiped with filters, 73.9% +/- 2.3% to 95.3% +/- 1.7% for the stainless steel surface wiped with filters, and 18.2% +/- 1.4% to 372.8% +/- 8.0% for the stainless steel surface wiped with Kimwipes. Results were best for ifosfamide and cyclophosphamide. Kimwipes were deemed ineffective for this monitoring method because an ingredient interfered with the quantitative analytical tests. A wipe-sampling, desorption, and HPLC method for monitoring surface contamination by selected antineoplastic agents was sufficiently accurate and sensitive to evaluate surfaces typically found in both the pharmacy and drug administration areas of oncology treatment facilities. PMID:11862639

  19. Chemical crowd control agents.

    Science.gov (United States)

    Menezes, Ritesh G; Hussain, Syed Ather; Rameez, Mansoor Ali Merchant; Kharoshah, Magdy A; Madadin, Mohammed; Anwar, Naureen; Senthilkumaran, Subramanian

    2016-03-01

    Chemical crowd control agents are also referred to as riot control agents and are mainly used by civil authorities and government agencies to curtail civil disobedience gatherings or processions by large crowds. Common riot control agents used to disperse large numbers of individuals into smaller, less destructive, and more easily controllable numbers include chloroacetophenone, chlorobenzylidenemalononitrile, dibenzoxazepine, diphenylaminearsine, and oleoresin capsicum. In this paper, we discuss the emergency medical care needed by sufferers of acute chemical agent contamination and raise important issues concerning toxicology, safety and health. PMID:26658556

  20. Decontamination Data - Blister Agents

    Data.gov (United States)

    U.S. Environmental Protection Agency — Decontamination efficacy data for blister agents on various building materials using various decontamination solutions This dataset is associated with the following...

  1. Multi-Analyte Separation Methods for HPLC Determination of the Active Ingredients of Pesticides

    International Nuclear Information System (INIS)

    The practical quality control of selected pesticides, such as carbamates, organophosphorous compounds, phthalimides, pyrethroids, with HPLC is described. Detailed descriptions are given of materials and methods used, including sample preparation and HPLC operating conditions. The relationship between pH value of the HPLC eluent and the logPow is discussed, illustrated by chromatograms, graphics and tables. The results are also compared with those elaborated by. E. Dudar and presented above. (author)

  2. RP-HPLC Determination of 1,3-Dideoxygalactonojirimycin in Bombycis Faeces

    Institute of Scientific and Technical Information of China (English)

    QI Hui; ZHAO Hui; DING Zhen-ying; ZHU Yuan-yuan

    2011-01-01

    Objective To establish a simple and rapid method for the determination of 1,3-dideoxygalactonojirimycin in Bombycis Faeces, a potent glucosidase inihibitor, by HPLC. Methods A RP-HPLC method with fluorescence detection has been developed. Results The HPLC method developed in this research has a good reliability including accuracy and precision. The detection limit was less than 72 ng. Conclusion This method is sufficiently sensitive for determining 1,3-dideoxygalactonojirimycin in Bombycis Faeces and other related products.

  3. Immobilized lipodisks as model membranes in high-throughput HPLC-MS analysis

    OpenAIRE

    Meiby, Elinor; Morin Zetterberg, Malin; Ohlson, Sten; Agmo Hernández, Víctor; Edwards, Katarina

    2013-01-01

    Lipodisks, also referred to as polyethylene glycol (PEG)-stabilized bilayer disks, have previously been demonstrated to hold great potential as model membranes in drug partition studies. In this study, an HPLC-MS system with stably immobilized lipodisks is presented. Functionalized lipodisks were immobilized on two different HPLC support materials either covalently by reductive amination or by streptavidin-biotin binding. An analytical HPLC column with immobilized lipodisks was evaluated by a...

  4. Isolation of 163Ho from dysprosium target material by HPLC for neutrino mass measurements

    International Nuclear Information System (INIS)

    The rare earth isotope 163Ho is of interest for neutrino mass measurements. This report describes the isolation of 163Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, 163Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm-3 α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized by MC-ICP-MS to determine the 163Ho/165Ho ratio, 163Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4 x 105 for Dy. The isolated Ho fraction contained 24.8 ± 1.3 ng of 163Ho corresponding to holmium recovery of 72 ± 3%.

  5. A rapid HPLC method for simultaneous determination of tretinoin and isotretinoin in dermatological formulations.

    Science.gov (United States)

    Tashtoush, Bassam M; Jacobson, Elaine L; Jacobson, Myron K

    2007-02-19

    A rapid method using an isocratic high-pressure liquid chromatography and UV detection for determination of both all-trans retinoic acid (tretinoin) and 13-cis retinoic acid (isotretinoin) in dermatological preparations is presented. Tretinoin and isotretinoin samples were extracted with acetonitrile by a procedure that can be completed in less than 10 min. Subsequent separation and quantification of amounts as low as 10 pmol was accomplished in less than 15 min using reversed-phase HPLC with isocratic elution with 0.01% trifluoroacetic acid (TFA)/acetonitrile (15:85, v/v). Validation experiments confirmed the precision and accuracy of the method. When applied to commercial tretinoin samples, recoveries of 104.9% for cream formulations and 107.7% for gel formulations were obtained. Application of the method for analysis of a tretinoin cream exposed to solar simulated light (SSL) demonstrated detection of the major photoisomerization product isotretinoin as well as 9-cis retinoic acid, demonstrating the utility of the method for studies of tretinoin photostability. The method should also facilitate studies of the formulation compatibility and photocompatibility of tretinoin with agents that may improve its clinical tolerability. PMID:17045442

  6. Isolation of {sup 163}Ho from dysprosium target material by HPLC for neutrino mass measurements

    Energy Technology Data Exchange (ETDEWEB)

    Mocko, Veronika; Taylor, Wayne A.; Nortier, Francois M.; Engle, Jonathan W.; Pollington, Anthony D.; Kunde, Gerd J.; Rabin, Michael W.; Birnbaum, Eva R. [Los Alamos National Laboratory, Los Alamos, NM (United States). Chemistry Div.; Barnhart, Todd E.; Nickles, Robert J. [Univ. Wisconsinn, Madison, WI (United States). Dept. of Medical Physics

    2015-07-01

    The rare earth isotope {sup 163}Ho is of interest for neutrino mass measurements. This report describes the isolation of {sup 163}Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, {sup 163}Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm{sup -3} α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized by MC-ICP-MS to determine the {sup 163}Ho/{sup 165}Ho ratio, {sup 163}Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4 x 10{sup 5} for Dy. The isolated Ho fraction contained 24.8 ± 1.3 ng of {sup 163}Ho corresponding to holmium recovery of 72 ± 3%.

  7. Development and validation of an HPLC method to determine metabolites of 5-hydroxymethylfurfural (5-HMF).

    Science.gov (United States)

    Hardt-Stremayr, Magdalena; Bernaskova, Marketa; Hauser, Stefanie; Kunert, Olaf; Guo, Xinghua; Stephan, Janette; Spreitz, Josef; Lankmayr, Ernst; Schmid, Martin G; Wintersteiger, Reinhold

    2012-10-01

    The food component 5-hydroxymethylfurfural is supposed to have antioxidative properties and is therefore used as an acting agent in a novel anticancer infusion solution, named Karal®, and an oral supplementation. Previous studies showed that after oral and intravenous application, the substance is completely decomposed to its metabolites: 5-hydroxymethylfuroic acid, 2,5-furandicarboxylic acid, and N-(hydroxymethyl)furoyl glycine. The formation of a fourth metabolite, namely 5-sulphoxymethylfurfural, is still not clarified according to literature. Due to commercial unavailability, synthesis of 5-sulphoxymethylfurfural was conducted and a synthesis procedure for N-(hydroxymethyl)furoyl glycine had to be developed. Identification of the synthesised compounds was proven by LC-MS and NMR. An appropriate HPLC method was established to obtain good separation of the four possible metabolic substances and 5-hydroxymethylfurfural within 12 min via a HILIC column (150 × 4.6 mm, 5 μm) using a gradient grade system switching from mobile phase A (ACN/ammonium formate 100 mM, pH 2.35, 95:5, v/v) to mobile phase B (ACN/ammonium formate 100 mM, pH 2.35, 85:15, v/v). The procedure was afterward validated following ICH guidelines in terms of selectivity, linearity, precision, LOD, and LOQ. PMID:22941583

  8. Simultaneous analysis of eight bioactive compounds in Danning tablet by HPLC-ESI-MS and HPLC-UV.

    Science.gov (United States)

    Liu, Runhui; Zhang, Jiye; Liang, Mingjin; Zhang, Weidong; Yan, Shikai; Lin, Min

    2007-02-19

    A high performance liquid chromatography (HPLC) coupled with electrospray tandem mass spectrometry (ESI-MS) and ultraviolet detector (UV) has been developed for the simultaneous analysis of eight bioactive compounds in Danning tablet (including hyperin, hesperidin, resveratrol, nobiletin, curcumine, emodin, chrysophanol, and physcion), a widely used prescription of traditional Chinese medicine (TCM). The chromatographic separation was performed on a ZORBAX Extend C(18) analytical column by gradient elution with acetonitrile and formate buffer (containing 0.05% formic acid, adjusted with triethylamine to pH 5.0) at a flow rate of 0.8 ml/min. The eight compounds in Danning tablet were identified and their MS(n) fractions were elucidated by using HPLC-ESI-MS, and the contents of these compounds were determined by using HPLC-UV method. The standard calibration curves were linear between 5.0 and 100 microg/ml for hyperin, 10-200 microg/ml for hesperidin, 1.0-150 microg/ml for resveratrol, 2.0-120 microg/ml for nobiletin, 2.0-225 microg/ml for curcumine, 20-300 microg/ml for emodin, 2.0-200 microg/ml for chrysophanol, and 20-250 microg/ml for physcion with regression coefficient r(2)>0.9995. The intra-day and inter-day precisions of this method were evaluated with the R.S.D. values less than 0.7% and 1.3%, respectively. The recoveries of the eight investigated compounds were ranged from 99.3% to 100.2% with R.S.D. values less than 1.5%. This method was successfully used to determine the 8 target compounds in 10 batches of Danning tablet. PMID:17079108

  9. HPLC-MS Analysis of Chloramphenicol Residues in Milk and Powdered Milk Products

    Directory of Open Access Journals (Sweden)

    Bošnir, J.

    2007-02-01

    Full Text Available Chloramphenicol (CAP is a broad-spectrum antibiotic with bacteriostatic action but also has toxic properties, which is why its presence in food and feed is prohibited in Croatia and the European Union.In the aim of consumer protection it is essential to develop a sensitive analytical method for detection of CAP fractions lower than w = 0.3 µg kg-1. For the efficient control and monitoring of CAP, a rapid, sensitive, and selective method for its identification and quantification, using highperformance liquid chromatography in combination with mass spectrometry LC-MS, has been developed.The cleaning procedure was based on the AOAC official method 993.32. HPLC-MS analysis used the ODS Hypersile column and the water/acetonitrile gradient. Electrospray negative ionization (neg ESI was used before single ion monitoring (SIM detection of three m/z 321, 323 and 325. As additional criteria, the ratio between these masses in real and spiked milk samples was also investigated in accordance with theoretical values of the isotope pattern for 2 chlorine atoms present in the analyte.The detection limit of 0.1 µg kg-1 was achieved. The mean value of recovery was 94 %, the correlation coefficient of the calibration curves calculated for 2 m/z values was higher than 0.99.Fourty samples of milk and milk products were tested with the HPLC-MS method, and obtained results showed that samples had CAP 0.37, 0.29, 0.39 µg kg-1, respectively. All the other analysed samples contained CAP concentrations below the detection limit.

  10. Analysis of ochratoxin A in pig tissues using high pressure liquid chromatography (HPLC) and liquid chromatography tandem mass spectrometry (LC/MS/MS) as confirmative methods

    OpenAIRE

    Milićević Dragan R.; Jurić Verica B.; Stefanović Srđan M.; Vesković-Moračanin Slavica M.; Janković Saša I.

    2009-01-01

    Two different analytical methods for the determination and confirmation of ochratoxin A (OTA) in blood serum, kidney and liver of pigs have been compared. Sample clean-up was based on liquid-liquid phase extraction. The detection of OTA was accomplished with high-performance liquid chromatography (HPLC) combined either with fluorescence detection (FL) or electro spray ionization (ESI+) tandem mass spectrometry (MS-MS). Comparative method evaluation was based on the investigation of 82 samples...

  11. A double-cartridge SPE-HPLC-UV method for monitoring a humanfriendly anticancer in plasma: Ketoglutarate levels in metastatic carcinoma

    OpenAIRE

    Michail, K.; Rozet, Eric; HUBERT, Philippe; Wintersteiger, R.

    2010-01-01

    We present a fully validated HPLC-UV assay for the concurrent quantification of ketoglutaric acid and hydroxymethylfurfural, a ‘targeted therapy’ composition inducing a synergistic metabolic distress to the tumoral microenvironment. The analytes were exclusively extracted from the biomatrix via a combined-cartridge solid phase extraction assembly. The method is based on derivatizing both analytes with 2-nitrophenylhydrazine directed to their chemically divergent but commonly oc...

  12. Selenite biotransformation during brewing. Evaluation by HPLC-ICP-MS.

    Science.gov (United States)

    Sánchez-Martínez, Maria; da Silva, Erik Galvão P; Pérez-Corona, Teresa; Cámara, Carmen; Ferreira, Sergio L C; Madrid, Yolanda

    2012-01-15

    Yeast (Saccharomyces cerevisiae) and lactic bacteria have shown their ability to accumulate and transform inorganic selenium into organo Se compounds. The objective of this work was to evaluate selenium biotransformation during brewing by using S. cerevisiae and Saccharomyces uvarum for Ale and Lager fermentation, respectively. Se-enriched beer was produced by the addition of sodium selenite (0, 0.2, 1.0, 2.0, 10.0, 20.0 μg Se mL(-1), respectively) to the fermentation media composed of yeast, malt extract and water. The alcoholic fermentation process was not affected by the presence of selenium regardless of the type of Saccharomyces being used. The percentage of selenium incorporated into beer, added between 1.0 and 10 μg mL(-1) was 55-60% of the selenium initially present. Se-compounds in post-fermentation (beer and yeast) products were investigated by using an analytical methodology based on HPLC-ICP-MS. For this purpose, several sample treatments, including ultrasonic-assisted enzymatic hydrolysis, in conjunction with different separation mechanisms like dialysis and anion exchange HPLC chromatography were applied for unambiguously identifying Se-species that produce during brewing. Selenomethionine was the main selenium compound identified in beer and yeast, being this species in the only case of the former not associated to peptides or proteins. PMID:22265498

  13. Determination of capsinoids by HPLC-DAD in capsicum species.

    Science.gov (United States)

    Singh, Satyavan; Jarret, Robert; Russo, Vincent; Majetich, George; Shimkus, Joel; Bushway, Rodney; Perkins, Brian

    2009-05-13

    Capsicum fruits contain a newly discovered phytochemical called capsinoids. Because little is known about the quantities of these compounds in both sweet and pungent pepper fruits, a high-performance liquid chromatography (HPLC) method was developed to identify and quantify the capsinoids (naturally present E-capsiate and dihydrocapsiate) utilizing fruit obtained from a variety of Capsicum spp. in the U.S. Department of Agriculture's Capsicum germplasm collection. Capsinoids were extracted with acetonitrile, filtered, and analyzed using an HPLC system equipped with a C(18) monolithic column, gradient pump, and diode array detector. The elution solvents were acetonitrile and water (60:40) with an isocratic flow rate of 1.0 mL/min. Forty-nine samples representing distinct morphotypes of four cultivated species ( C. annuum var. annuum, C. annuum var. glabriusculum, C. baccatum , C. chinense , and C. frutescens ) contained detectable levels (11-369 microg/g) of E-capsiate quantified at a wavelength of 280 nm. Nine of the E-capsiate-containing samples also had dihydrocapsiate (18-86 micro/g). Gas chromatography with a mass spectrometry detector (GC-MS) confirmed the presence of these compounds in the Capsicum spp. PMID:19415923

  14. Determination of ethylene thiourea in urine by HPLC-DAD.

    Science.gov (United States)

    El Balkhi, Souleiman; Sandouk, Pierre; Galliot-Guilley, Martine

    2005-01-01

    Ethylene thiourea (ETU) is a metabolite of ethylenebisdithiocarbamates (EBDCs); it is the best indicator of exposure to these fungicides. Therefore, high-performance liquid chromatography with photodiode-array detection (HPLC-DAD) was optimized and validated for the determination of ETU in human urines. Urine samples were extracted by solid-phase extraction using Extrelut and analyzed using HPLC-DAD set at 231 nm. The analyses were carried out using a mobile phase of 0.01 M phosphate buffer (pH 4.5) on a C18 Uptisphere NEC-5-20, 250- x 4.6-mm x 5-microm column. The internal standard used was 4-pyridinecarboxylic acid hydrazide. The method was successfully validated in compliance with requirements set by the International Committee on Harmonization 1996. The lower limit of quantitation was at 1 microg/L, and the linearity was studied from 1 to 100 microg/L. There were 272 urine samples collected from farmers exposed to EBDCs in different regions in France analyzed in this study. PMID:15975251

  15. HPLC assisted Raman spectroscopic studies on bladder cancer

    Science.gov (United States)

    Zha, W. L.; Cheng, Y.; Yu, W.; Zhang, X. B.; Shen, A. G.; Hu, J. M.

    2015-04-01

    We applied confocal Raman spectroscopy to investigate 12 normal bladder tissues and 30 tumor tissues, and then depicted the spectral differences between the normal and the tumor tissues and the potential canceration mechanism with the aid of the high-performance liquid chromatographic (HPLC) technique. Normal tissues were demonstrated to contain higher tryptophan, cholesterol and lipid content, while bladder tumor tissues were rich in nucleic acids, collagen and carotenoids. In particular, β-carotene, one of the major types of carotenoids, was found through HPLC analysis of the extract of bladder tissues. The statistical software SPSS was applied to classify the spectra of the two types of tissues according to their differences. The sensitivity and specificity of 96.7 and 66.7% were obtained, respectively. In addition, different layers of the bladder wall including mucosa (lumps), muscle and adipose bladder tissue were analyzed by Raman mapping technique in response to previous Raman studies of bladder tissues. All of these will play an important role as a directive tool for the future diagnosis of bladder cancer in vivo.

  16. Monitoring the chemical and physical stability for tromethamine excipient in a lipid based formulation by HPLC coupled with ELSD.

    Science.gov (United States)

    Rodríguez, Shirley A; Qiu, Fenghe; Mulcey, Michael; Weigandt, Karen; Tamblyn, Toby

    2015-11-10

    Tromethamine, a UV-transparent amine base excipient, was used in the liquid phase of a self-emulsifying drug delivery system-soft gelatin capsule (SEDDS-SGC) formulation as an emulsification agent and to improve solubilization of the active drug. The level of this excipient was found to be decreasing in aged and stressed drug product capsules. The decrease could potentially affect oral bioavailability of the drug; should the amount of solubilizer decrease enough to lead to precipitation of the active drug from the formulation. Therefore, further investigation was warranted. HPLC coupled with evaporative light scattering detection (ELSD) was used to monitor the physical and chemical stability of tromethamine in the SEDDS-SGC formulation. Confirmation of the tromethamine interaction products was done by LC-MS. PMID:26254033

  17. Quantification of 4'-geranyloxyferulic acid (GOFA) in honey samples of different origin by validated RP-HPLC-UV method.

    Science.gov (United States)

    Genovese, Salvatore; Taddeo, Vito Alessandro; Fiorito, Serena; Epifano, Francesco

    2016-01-01

    Natural honey has been employed as a nutraceutical agent with benefits and therapeutic promises for humans for many centuries. It has been largely used as food and medicine by all generations, traditions, and civilizations, both ancient and modern. Several chemicals having beneficial effects for human health have been reported as components of natural honey and these include sugars, organic acids, aminoacids, minerals, and vitamins. Also some important phytochemicals have been described and these comprise tannins, flavonoids, terpenes, saponins, and alkaloids. In this note it is described the successful application of a RP HPLC-UV-vis method for the separation and quantification of 4'-geranyloxyferulic acid (GOFA) in four honey samples of different origin. Concentration values showed a great variation between the four samples tested, being chestnut honey the one richest in GOFA (7.87 mg/g). The findings described herein represent the first example reported in the literature of the characterization of an oxyprenylated phenylpropanoid in honey. PMID:26421962

  18. Agent Development Toolkits

    CERN Document Server

    Singh, Aarti; Sharma, A K

    2011-01-01

    Development of agents as well as their wide usage requires good underlying infrastructure. Literature indicates scarcity of agent development tools in initial years of research which limited the exploitation of this beneficial technology. However, today a wide variety of tools are available, for developing robust infrastructure. This technical note provides a deep overview of such tools and contrasts features provided by them.

  19. Asimovian Adaptive Agents

    CERN Document Server

    Gordon, D F

    2011-01-01

    The goal of this research is to develop agents that are adaptive and predictable and timely. At first blush, these three requirements seem contradictory. For example, adaptation risks introducing undesirable side effects, thereby making agents' behavior less predictable. Furthermore, although formal verification can assist in ensuring behavioral predictability, it is known to be time-consuming. Our solution to the challenge of satisfying all three requirements is the following. Agents have finite-state automaton plans, which are adapted online via evolutionary learning (perturbation) operators. To ensure that critical behavioral constraints are always satisfied, agents' plans are first formally verified. They are then reverified after every adaptation. If reverification concludes that constraints are violated, the plans are repaired. The main objective of this paper is to improve the efficiency of reverification after learning, so that agents have a sufficiently rapid response time. We present two solutions: ...

  20. How do agents represent?

    Science.gov (United States)

    Ryan, Alex

    Representation is inherent to the concept of an agent, but its importance in complex systems has not yet been widely recognised. In this paper I introduce Peirce's theory of signs, which facilitates a definition of representation in general. In summary, representation means that for some agent, a model is used to stand in for another entity in a way that shapes the behaviour of the agent with respect to that entity. Representation in general is then related to the theories of representation that have developed within different disciplines. I compare theories of representation from metaphysics, military theory and systems theory. Additional complications arise in explaining the special case of mental representations, which is the focus of cognitive science. I consider the dominant theory of cognition — that the brain is a representational device — as well as the sceptical anti-representational response. Finally, I argue that representation distinguishes agents from non-representational objects: agents are objects capable of representation.

  1. Simultaneous Determination of Different Polyamines and their Mono-Acetylated Derivatives in Gastric Tissue by HPLC with Post-Column Derivatization

    OpenAIRE

    Raza, Muhammad; Al-Shabanah, Othman A

    2010-01-01

    A simple and highly sensitive procedure is described enabling the simultaneous determination of biogenic polyamines (PAs) and their related monoacetyl derivatives in stomach tissue. The method is based on HPLC using octane sulfonate as an ion-pairing agent employed in acetate buffers at pH 4.5. The application is accompanied with fluorescence detection followed by post-column derivatization with o-phthaldialdehyde at room temperature (20±0.5°C). N1- and N8-acetylspermidines (ASPD) can be dete...

  2. The role of dopamine transporter imaging agent [99mTc]TRODAT-1 in hemi-parkinsonism rat brain

    International Nuclear Information System (INIS)

    This study aims to investigate the relationship between the determination of dopamine level by high performance liquid chromatography (HPLC) with electrochemical detection (ECD) and the detection of dopamine transporter (DAT) counts using autoradiography with DAT image agent [99mTc]TRODAT-1. For striatal lesions, pretreatment of 6-hydroxydopamine (6-OHDA) in the medial forebrain bundle shows that autoradiogaphic labeling of striatum region is reduced to near-background level. Using HPLC with ECD, unilateral 6-OHDA treatment is associated with significant (p99mTc]TRODAT-1 for the evaluation of animal DAT

  3. Determination of cadmium and lead species and phytochelatins in pea (Pisum sativum) by HPLC-ICPMS and HPLC-ESIMSn

    International Nuclear Information System (INIS)

    Full text: Trace elements play an important role in the functioning of life on our planet. Some of them can be highly toxic, whereas others can be essential. These effects are very often related to particular form in which the element is present. Often these different chemical forms of a particular element or its compounds are referred to as 'species'. Cadmium and lead are widespread heavy metal pollutants released into the environment by human activities. The presence of Pb2+ and Cd2+ in the environment leads to a numerous disturbances in many metabolic processes in plants. Inhibition of growth is a major symptom. Hyphenated techniques, such as HPLC-ICPMS and HPLC-ESIMSn seem to be the best analytical instruments to study metal speciation in plants. In our study, we used hyphenated techniques to identify compounds engaged in Cd and Pb metabolism and to perform analysis of metal complexes induced in Pisum sativum exposed to cadmium and lead. These identified compounds might be valuable source of information to study metal accumulation mechanism for bioremediation processes. (author)

  4. Development of Tc-99m Imaging Agents for Abeta Plaques

    International Nuclear Information System (INIS)

    Development of SPECT imaging agents based on Tc-99m targeting Aβ plaques is useful for diagnosis of Alzheimer's disease (AD). A stilbene derivative, [11C]SB-13, showing promise in detecting senile plaques present in AD patients has been reported previously. Based on the 4(prime)-amino-stilbene core structure we have added substituted groups through which a chelating group, N2S2, was conjugated. We report herein a series of Tc-99m labeled stilbene derivative conjugated with a TcO[N2S2] core. The syntheses of stilbenes containing a N2S2 chelating ligand are achieved by a scheme shown. Lipophilic 99mTc stilbene complexes were successfully prepared and purified through HPLC. Preliminary results of in vitro labeling of brain sections from transgenic mice showed very promising plaque labeling. These 99mTc stilbene derivatives are warranted for further evaluations as potential imaging agents targeting amyloid plaques.

  5. Spectrophotometric and HPLC determination of deflazacort in pharmaceutical dosage forms

    Directory of Open Access Journals (Sweden)

    Amarilis Scremin

    2010-06-01

    Full Text Available Deflazacort (DFZ is a glucocorticoid used as an anti-inflammatory and immunosuppressant drug. No official methods are available for DFZ determination in pharmaceutical formulations. The objective of this study was to develop, validate and compare spectrophotometric (UV and colorimetric and high-performance liquid chromatography (HPLC methods, for the quantitative determination of DFZ in tablets and oral suspension. For the UV method, ethanol was used as the solvent, with detection at 244 nm. The colorimetric method was based on the redox reaction with blue tetrazolium in alkaline medium, with detection at 524 nm. The method by HPLC was carried out using a C18 column, mobile phase consisting of acetonitrile:water (80:20, v/v with a flow rate of 1.0 mL min-1 and detection at 244 nm. The methods proved linear (r > 0.999, precise (RSD 97%. Statistical analysis of the results indicated that the UV and HPLC methods were statistically equivalent, while the values obtained for the colorimetric method differed significantly from the other methods.O deflazacorte (DFZ é um fármaco glicocorticóide usado como antiinflamatório e imunossupressor. Métodos oficiais não estão disponíveis para a determinação de DFZ em formas farmacêuticas. Este estudo teve como objetivo desenvolver, validar e comparar métodos por espectrofotometria (UV e colorimetria e cromatografia líquida de alta eficiência (CLAE, na determinação quantitativa de DFZ em comprimidos e suspensão oral. O método por UV utilizou etanol como solvente, com detecção em 244 nm. O método colorimétrico foi baseado na reação de redução com azul de tetrazólio em meio alcalino, com detecção em 524 nm. O método por CLAE utilizou coluna C18; fase móvel constituída de acetonitrila:água (80:20, v/v, com fluxo de 1,0 mL min-1 e detecção em 244 nm. Os métodos foram lineares (r > 0,999; precisos (RSD 97%. As análises estatísticas dos resultados obtidos indicaram que os m

  6. Contrast Agent in Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Vu-Quang, Hieu

    2015-01-01

    Nanoparticles have been employed as contrast agent in magnetic resonance imaging (MRI) in order to improve sensitivity and accuracy in diagnosis. In addition, these contrast agents are potentially combined with other therapeutic compounds or near infrared bio-imaging (NIR) fluorophores to obtain...... theranostic or dual imaging purposes, respectively. There were two main types of MRI contrast agent that were synthesized during this PhD project including fluorine containing nanoparticles and magnetic nanoparticles. In regard of fluorine containing nanoparticles, there were two types contrast agent...... cancer cells for cancer diagnosis in MRI. F127-Folate coated SPION were stable in various types of suspension medium for over six months. They could specifically target folate receptor of cancer cells in vitro and in vivo thus enhancing the contrast in MRI T2/T2* weighted images. These are preliminary...

  7. Behavior-based dual dynamic agent architecture

    Institute of Scientific and Technical Information of China (English)

    仵博; 吴敏; 曹卫华

    2003-01-01

    The objective of the architecture is to make agent promptly and adaptively accomplish tasks in the real-time and dynamic environment. The architecture is composed of elementary level behavior layer and high level be-havior layer. In the elementary level behavior layer, the reactive architecture is introduced to make agent promptlyreact to events; in the high level behavior layer, the deliberation architecture is used to enhance the intelligence ofthe agent. A confidence degree concept is proposed to combine the two layers of the architecture. An agent decisionmaking process is also presented, which is based on the architecture. The results of experiment in RoboSoccer simu-lation team show that the proposed architecture and the decision process are successful.

  8. Users, Bystanders and Agents

    DEFF Research Database (Denmark)

    Krummheuer, Antonia Lina

    2015-01-01

    Human-agent interaction (HAI), especially in the field of embodied conversational agents (ECA), is mainly construed as dyadic communication between a human user and a virtual agent. This is despite the fact that many application scenarios for future ECAs involve the presence of others. This paper...... the construction of the agent’s identity, and (3) how HAI, as a mediated interaction, is framed by an asymmetric participation framework. The paper concludes by suggesting various participation roles, which may inform development of ECAs....

  9. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  10. Chemical Profiling (HPLC-NMR & HPLC-MS, Isolation, and Identification of Bioactive Meroditerpenoids from the Southern Australian Marine Brown Alga Sargassum paradoxum

    Directory of Open Access Journals (Sweden)

    Robert Brkljača

    2014-12-01

    Full Text Available A phytochemical investigation of a southern Australian marine brown alga, Sargassum paradoxum, resulted in the isolation and identification of four new (5, 9, 10, and 15 and nine previously reported (1, 2, 6–8, and 11–14 bioactive meroditerpenoids. HPLC-NMR and HPLC-MS were central to the identification of a new unstable compound, sargahydroquinal (9, and pivotal in the deconvolution of eight (1, 2, 5–7, and 10–12 other meroditerpenoids. In particular, the complete characterization and identification of the two main constituents (1 and 2 in the crude dichloromethane extract was achieved using stop-flow HPLC-NMR and HPLC-MS. This study resulted in the first acquisition of gHMBCAD NMR spectra in the stop-flow HPLC-NMR mode for a system solely equipped with a 60 μL HPLC-NMR flow cell without the use of a cold probe, microcoil, or any pre-concentration.

  11. Separation, purification and identification of flavonoid glycosides using reversed phase hplc

    International Nuclear Information System (INIS)

    Optimal high performance liquid chromatography (HPLC) separation conditions and semi-preparative scale isolation of flavonoid glycosides from three plant species namely Vitex nagunda, Rubus ulmifolious and Malotus philipensis is reported. Identification of purified flavonoid glycoside was achieved using spiking technique in HPLC. (author)

  12. Theoretische en practische aspecten van het gebruik van micro-HPLC

    NARCIS (Netherlands)

    de Fluiter P; Jansen EHJM

    1992-01-01

    A practical and theoretical approach for the implementation of micro high performance liquid chromatography (HPLC) is described. A new simple and rapid test procedure was developed in wich a HPLC system can be validated for its suitability for micro-bore columns. It appeared that the detector flow

  13. Size exclusion HPLC of proteins for evaluation of durum wheat quality

    Science.gov (United States)

    The present research aimed to assess size exclusion HPLC (SE-HPLC) in protein molecular weight distribution determination for quality evaluation of durum semolina. Semolina samples were milled from 13 durum genotypes grown at 7 locations in 2009 and 2010 in ND. Sodium dodecyl sulfate (SDS) buffer ...

  14. [Skin tanning and light protection-theory, agents and analytic aspects. 1. Skin tanning and skin tanning agents].

    Science.gov (United States)

    Matissek, R

    1984-10-01

    The different approaches to achieving skin tanning with emphasis on natural tanning, due to UV radiation of the sun or solaria, and artificial tanning through tannings agents are described. In contrast to the artificial tan the natural tan is a protection against UV radiation and is caused by pigmentation (melanin formation). The artificial tanning is based on a chemical reaction usually by means of dihydroxy acetone (melanoidin formation). Reaction mechanisms by both agents are reported. The determination of dihydroxy acetone in cosmetic tanning preparations by TLC, GC, HPLC, enzymatic tests and by a new method for capillary GC including sample preparation is described. When exceeding the natural protection mechanisms the skin should be protected by physico-chemical measures. The active principles in sunscreens are the UV filtering substances. UV filters permitted in the EG are listed. 2-Hydroxy benzophenone is used as an example to explain the mechanism of UV filtering substances. Analysis of UV filtering substances in cosmetic sunscreens by TLC, GC, HPLC is described as well as a fast and simple method for separation of lipophilic UV filters followed by capillary GC determination. PMID:6506884

  15. HPLC Measurement of the DNA Oxidation Biomarker, 8-oxo-7,8-dihydro-2'-deoxyguanosine, in Cultured Cells and Animal Tissues.

    Science.gov (United States)

    Chepelev, Nikolai L; Kennedy, Dean A; Gagné, Remi; White, Taryn; Long, Alexandra S; Yauk, Carole L; White, Paul A

    2015-01-01

    Oxidative stress is associated with many physiological and pathological processes, as well as xenobiotic metabolism, leading to the oxidation of biomacromolecules, including DNA. Therefore, efficient detection of DNA oxidation is important for a variety of research disciplines, including medicine and toxicology. A common biomarker of oxidatively damaged DNA is 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo; often erroneously referred to as 8-hydroxy-2'-deoxyguanosine (8-OH-dGuo or 8-oxo-dG)). Several protocols for 8-oxo-dGuo measurement by high pressure liquid chromatography with electrochemical detection (HPLC-ED) have been described. However, these were mainly applied to purified DNA treated with pro-oxidants. In addition, due to methodological differences between laboratories, mainly due to differences in analytical equipment, the adoption of published methods for detection of 8-oxo-dGuo by HPLC-ED requires careful optimization by each laboratory. A comprehensive protocol, describing such an optimization process, is lacking. Here, a detailed protocol is described for the detection of 8-oxo-dGuo by HPLC-ED, in DNA from cultured cells or animal tissues. It illustrates how DNA sample preparation can be easily and rapidly optimized to minimize undesirable DNA oxidation that can occur during sample preparation. This protocol shows how to detect 8-oxo-dGuo in cultured human alveolar adenocarcinoma cells (i.e., A549 cells) treated with the oxidizing agent KBrO3, and from the spleen of mice exposed to the polycyclic aromatic hydrocarbon dibenzo(def,p)chrysene (DBC, formerly known as dibenzo(a,l)pyrene, DalP). Overall, this work illustrates how an HPLC-ED methodology can be readily optimized for the detection of 8-oxo-dGuo in biological samples. PMID:26273842

  16. HPLC estimation of berberine in Tinospora cordifolia and Tinospora sinensis

    Directory of Open Access Journals (Sweden)

    Srinivasan G

    2008-01-01

    Full Text Available A high-performance liquid chromatographic method for the estimation of berberine in the stem of Tinospora cordifolia (Willd. Miers. ex Hook.f. and Thoms. and Tinospora sinensis (Lour. Merrill is described. The dried stems of T. cordifolia and T. sinensis were defatted with petroleum ether (60-80°. The marc was dried and further extracted with methanol. The concentration of berberine in methanol extract was determined using a C-18 reverse phase column with a mobile phase of acetonitrile:water (10:90 v/v at a flow rate of 0.6 ml/min and with UV detection at 266 nm. TLC and HPLC comparison of both the species revealed significant variation in the chemical constitution of the two species. This observation becomes important in the context of the use of T. sinensis in place of the genuine drug T. cordifolia .

  17. HPLC Estimation of berberine in Tinospora cordifolia and Tinospora sinensis.

    Science.gov (United States)

    Srinivasan, G V; Unnikrishnan, K P; Rema Shree, A B; Balachandran, Indira

    2008-01-01

    A high-performance liquid chromatographic method for the estimation of berberine in the stem of Tinospora cordifolia (Willd.) Miers. ex Hook.f. and Thoms. and Tinospora sinensis (Lour.) Merrill is described. The dried stems of T. cordifolia and T. sinensis were defatted with petroleum ether (60-80 degrees ). The marc was dried and further extracted with methanol. The concentration of berberine in methanol extract was determined using a C-18 reverse phase column with a mobile phase of acetonitrile:water (10:90 v/v) at a flow rate of 0.6 ml/min and with UV detection at 266 nm. TLC and HPLC comparison of both the species revealed significant variation in the chemical constitution of the two species. This observation becomes important in the context of the use of T. sinensis in place of the genuine drug T. cordifolia. PMID:20390090

  18. Fatty acids in erythrocytes measured by isocratic HPLC.

    Science.gov (United States)

    Abushufa, R; Reed, P; Weinkove, C

    1994-09-01

    We developed an isocratic reversed-phase HPLC method to measure arachidonic, palmitoleic, linoleic, eicosatrienoic, oleic, palmitic, and stearic acids from hydrolyzed erythrocytes. Washed erythrocytes were heated in methanol:HCl and the fatty acids extracted into hexane:amyl alcohol. After derivatization with 4-bromomethyl-7-methoxycoumarin, samples diluted in mobile phase (acetonitrile:water, 85:15 by vol) were injected onto a 250 x 4.6 mm C18 column, and the eluted fatty acids were detected fluorometrically. For all analytes, the mean within-batch CV was 8.2% (5.5-10.8%), the mean limit of detection was 7.0 mumol/L, a linear response was maintained up to 400 mumol/L, and results agreed well with those by gas chromatography. The addition of antioxidant (butylated hydroxytoluene) was essential for sample stability. We discuss hydrolysis and extraction times, derivatization temperature, critical steps in chromatography, and concentration units. PMID:8070079

  19. Quantitative and qualitative HPLC analysis of thermogenic weight loss products.

    Science.gov (United States)

    Schaneberg, B T; Khan, I A

    2004-11-01

    An HPLC qualitative and quantitative method of seven analytes (caffeine, ephedrine, forskolin, icariin, pseudoephedrine, synephrine, and yohimbine) in thermogenic weight loss preparations available on the market is described in this paper. After 45 min the seven analytes were separated and detected in the acetonitrile: water (80:20) extract. The method uses a Waters XTerra RP18 (5 microm particle size) column as the stationary phase, a gradient mobile phase of water (5.0 mM SDS) and acetonitrile, and a UV detection of 210 nm. The correlation coefficients for the calibration curves and the recovery rates ranged from 0.994 to 0.999 and from 97.45% to 101.05%, respectively. The qualitative and quantitative results are discussed. PMID:15587578

  20. Arsenic speciation. HPLC followed by ICP-MS or INAA

    International Nuclear Information System (INIS)

    Sensitivities for the measurement of four arsenic species, AsIII, AsV, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), in environmental waters and rice extracts by a new neutron activation analysis (NAA) method using pre-separation of the species by liquid chromatography were determined. A manual fraction collection was used to isolate the species, followed by instrumental neutron activation analysis procedures. The sensitivities determined for arsenic species in the samples varied from 1.21 to 1.47 ng per vial or about 30 μg x L-1 in sample solutions which translates to about 900 ng arsenic per gram of rice for our HPLC-NAA experiments. (author)