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Sample records for agent combining hplc

  1. 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.

  2. 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 ...

  3. 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

  4. 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...

  5. 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 ...

  6. 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.

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

    Science.gov (United States)

    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

    2015-07-01

    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 sensitive tool to quantitate LPS. The combination of the LAL and HPLC/MS/MS analyses provided new evidence for the intrinsic capacity of plasma lipoproteins and phospholipid transfer protein to neutralize the activity of LPS. In a subset of patients with systemic inflammatory response syndrome, with documented infection but with a negative plasma LAL test, significant amounts of LPS were measured by the HPLC/MS/MS method. Patients with the highest plasma LPS concentration were more severely ill. HPLC/MS/MS is a relevant method to quantitate endotoxin in a sample, to assess the efficacy of LPS neutralization, and to evaluate the proinflammatory potential of LPS in vivo. PMID:26023073

  8. 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.

  9. 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

  10. Quantitative analysis combined with chromatographic fingerprint for comprehensive evaluation of Xiaoer Chaigui Tuire granules by HPLC-DAD.

    Science.gov (United States)

    Liu, Hong-Ming; Nie, Lei

    2015-01-01

    Quantitative analysis of eight major components combined with chromatographic fingerprint based on high performance liquid chromatography coupled with diode array detector (HPLC-DAD) was developed for the quality evaluation of Xiaoer Chaigui Tuire granules (XCTG), a traditional Chinese medicine (TCM) preparation. Each compound was analyzed by comparing its retention time and UV spectrum of each chromatographic peak with the corresponding retention time and UV spectrum of each standard compound. Baseline separation was achieved on an Agilent Zorbax SB-C18 column with gradient elution of acetonitrile and 0.1% (v/v) phosphoric acid. The developed method was validated by linearity, precision, repeatability, stability and recovery and was subsequently applied to quality evaluation of 12 batches of XCTG with similarity analysis, principal component analysis and cluster analysis. Quantitative analysis combined with HPLC fingerprint could offer an efficient, reliable and practical approach for quality evaluation of XCTG.

  11. 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 ...

  12. 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 ...

  13. 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.

  14. Combining Targeted Agents With Modern Radiotherapy in Soft Tissue Sarcomas

    Science.gov (United States)

    Wong, Philip; Houghton, Peter; Kirsch, David G.; Finkelstein, Steven E.; Monjazeb, Arta M.; Xu-Welliver, Meng; Dicker, Adam P.; Ahmed, Mansoor; Vikram, Bhadrasain; Teicher, Beverly A.; Coleman, C. Norman; Machtay, Mitchell; Curran, Walter J.

    2014-01-01

    Improved understanding of soft-tissue sarcoma (STS) biology has led to better distinction and subtyping of these diseases with the hope of exploiting the molecular characteristics of each subtype to develop appropriately targeted treatment regimens. In the care of patients with extremity STS, adjunctive radiation therapy (RT) is used to facilitate limb and function, preserving surgeries while maintaining five-year local control above 85%. In contrast, for STS originating from nonextremity anatomical sites, the rate of local recurrence is much higher (five-year local control is approximately 50%) and a major cause of death and morbidity in these patients. Incorporating novel technological advancements to administer accurate RT in combination with novel radiosensitizing agents could potentially improve local control and overall survival. RT efficacy in STS can be increased by modulating biological pathways such as angiogenesis, cell cycle regulation, cell survival signaling, and cancer-host immune interactions. Previous experiences, advancements, ongoing research, and current clinical trials combining RT with agents modulating one or more of the above pathways are reviewed. The standard clinical management of patients with STS with pretreatment biopsy, neoadjuvant treatment, and primary surgery provides an opportune disease model for interrogating translational hypotheses. The purpose of this review is to outline a strategic vision for clinical translation of preclinical findings and to identify appropriate targeted agents to combine with radiotherapy in the treatment of STS from different sites and/or different histology subtypes. PMID:25326640

  15. 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

  16. 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

  17. HPLC and 31P NMR characterization of the reaction between antitumor platinum agents and the phosphorothioate chemoprotective agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721).

    Science.gov (United States)

    Thompson, D C; Wyrick, S D; Holbrook, D J; Chaney, S G

    1995-10-26

    In prior studies, we examined the effects of the radioprotective and chemoprotective agent WR-2721 [S-2-(3-aminopropylamino)ethylphosphorothioic acid] on the in vivo biotransformation of the cisplatin [cis-diamminedichloroplatinum(II)] analog ormaplatin [(d,I)trans-1,2-diaminocyclohexanetetrachloroplatinum(IV), Pt(dach)Cl4, (formerly called tetraplatin)]. Those data suggested that a direct interaction between WR-2721 and ormaplatin and/or the corresponding Pt(II) drug, Pt(dach)Cl2, may be occurring in vivo. This would be in contrast to the generally accepted hypothesis that WR-2721 is a prodrug that must first be converted by alkaline phosphatase to a free thiol compound, WR-1065, before any appreciable reactivity would be evident. However, the major biotransformation product observed in the peritoneal fluid, plasma, and all tissues was Pt(dach)(WR-1065). We report here on further investigations into the in vitro reactivity of Pt(dach) compounds with WR-2721 and WR-1065. Separation of reaction products resulting from incubation of Pt(dach)(malonato) with either WR-2721 or WR-1065 under physiological conditions gave profiles that were indistinguishable by reverse phase HPLC and cation exchange HPLC at two different pHs. 31P NMR characterization of the dephosphorylation of WR-2721 revealed essentially no loss of inorganic phosphate for up to 24 hr when incubated in unbuffered water at 30 degrees. In contrast, when incubated with a 1:1 molar ratio of cisplatin under the same conditions, the WR-2721 signal was decreased markedly in the first 5 min, and had disappeared almost completely by 1 hr. The signal corresponding to inorganic phosphate increased in parallel to the decrease in the WR-2721 signal. No intermediate formation of a complex containing both platinum and phosphate could be detected at any time. These data suggest that the reaction between WR-2721 and platinum complexes results in rapid dephosphorylation of WR-2721, and, consequently, that the reaction

  18. 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

  19. 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.

  20. 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...

  1. 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.

  2. 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

  3. Isolation and identification of arctiin and arctigenin in leaves of burdock (Arctium lappa L.) by polyamide column chromatography in combination with HPLC-ESI/MS.

    Science.gov (United States)

    Liu, Shiming; Chen, Kaoshan; Schliemann, Willibald; Strack, Dieter

    2005-01-01

    A simple method involving polyamide column chromatography in combination with HPLC-PAD and HPLC-ESI/MS for isolating and identifying two kinds of lignans, arctiin and arctigenin, in the leaves of burdock (Arctium lappa L.) has been established. After extraction of burdock leaves with 80% methanol, the aqueous phase of crude extracts was partitioned between water and chloroform and the aqueous phase was fractionated on a polyamide glass column. The fraction, eluting with 100% methanol, was concentrated and gave a white precipitate at 4 degrees C from which two main compounds were purified by semi-preparative HPLC. In comparison with the UV and ESI-MS spectra and the HPLC retention time of authentic standards, the compounds were determined to be arctiin and arctigenin. The extraction/separation technique was validated using an internal standard method.

  4. 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

  5. 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...

  6. 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.

  7. 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

  8. 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...

  9. 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.

  10. RP-HPLC method for the determination of losartan potassium and ramipril in combined dosage form

    Directory of Open Access Journals (Sweden)

    Rao K

    2010-01-01

    Full Text Available A simple, specific and accurate reverse phase liquid chromatographic method was developed for the simultaneous determination of losartan potassium and ramipril in table dosage forms. A hypersil ODS C18, 4.6×250 mm, 5 µm column in isocratic mode, with mobile phase acetonitrile:methanol:10 mM tetra butyl ammonium hydrogen sulphate in water in the ratio of 30:30:40% v/v/v was used. The flow rate was 1.0 ml/min and effluent was monitored at 210 nm. The retention times of losartan potassium and ramipril were 4.7 and 3.3 min, respectively. The linearity range for losartan potassium and ramipril were in the range of 0.04-100 µg/ml and 0.2-300 µg/ml, respectively. The proposed method was also validated and successfully applied to the estimation of losartan potassium and ramipril in combined tablet formulations.

  11. 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)

  12. 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.

  13. 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

  14. A new chiral derivatizing agent for the HPLC separation of α-amino acids on a standard reverse-phase column.

    Science.gov (United States)

    Kotthaus, A F; Altenbach, H-J

    2011-02-01

    A new chiral derivatizing agent for α-amino acids is described which leads to diastereomers that can be separated by reverse-phase HPLC with direct detection by a diode array detector. The main advantage of the presented procedure is the fact that an excess of the derivatizing reagent can be employed as the product exhibits an absorption maximum at 360 nm, while the reagent has its absorption maximum at 260 nm. Therefore, it is possible to suppress the reagent signal by a detection wavelength of 400 nm leading to an easy and general method for the enantioseparation of a mixture of DL-amino acids and the determination of the enantiomeric purity of α-amino acid as exemplified by 16 different α-amino acids.

  15. Validated RP-HPLC method development for the simultaneous estimation of Metformin and Glimepiride in combine tablet dosage form

    Directory of Open Access Journals (Sweden)

    Manoj Charde

    2016-12-01

    Full Text Available A force degradation profile of Metformin Hcl & Glimepiride in combine tablet dosage form on RP-HPLC was developed using Grace RP-C18 (4.6 x 150 mm, 5 µm in an gradient mode with mobile phase comprising  of Acetonitrile: Dihydrogen Pott.Phosphate (pH 2.5 using 0.1% OPA The flow rate was 0.7 mL/ min and effluent was monitored at 242 nm.. The retention times were found to be 2.06 min for MET and 5.80 min for GLIM. The assay shows a linear dynamic range of 250- 1250 µg/mL for MET and 1.0-5.0 µg/mL for GLIM. The calibration curves were linear (r2 = 0.999 for MET and r2 = 0.998 for GLIM over the entire linear range. Mean % recovery was found to be 99.80 % for MET and 98.93 % for  GLIM  with % RSD was NMT 2 for both estimations which fully agrees with system suitability which is in good agreement with labeled amount of formulation. The % RSD for Intra- Day & Inter-Day Precision was NMT than 2 for both the drugs. The developed method was validated as per ICH guidelines

  16. 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.

  17. 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

  18. Assessment of repeatability of composition of perfumed waters by high-performance liquid chromatography combined with numerical data analysis based on cluster analysis (HPLC UV/VIS - CA).

    Science.gov (United States)

    Ruzik, L; Obarski, N; Papierz, A; Mojski, M

    2015-06-01

    High-performance liquid chromatography (HPLC) with UV/VIS spectrophotometric detection combined with the chemometric method of cluster analysis (CA) was used for the assessment of repeatability of composition of nine types of perfumed waters. In addition, the chromatographic method of separating components of the perfume waters under analysis was subjected to an optimization procedure. The chromatograms thus obtained were used as sources of data for the chemometric method of cluster analysis (CA). The result was a classification of a set comprising 39 perfumed water samples with a similar composition at a specified level of probability (level of agglomeration). A comparison of the classification with the manufacturer's declarations reveals a good degree of consistency and demonstrates similarity between samples in different classes. A combination of the chromatographic method with cluster analysis (HPLC UV/VIS - CA) makes it possible to quickly assess the repeatability of composition of perfumed waters at selected levels of probability.

  19. 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)

  20. Combining biological agents and chemotherapy in the treatment of cholangiocarcinoma

    DEFF Research Database (Denmark)

    Jensen, Lars Henrik; Jakobsen, Anders

    2011-01-01

    is not always possible. Chemotherapy is effective and the combination of cisplatin and gemcitabine is considered a standard treatment of inoperable cholangiocarcinoma. Biological targeted treatment to date has minor effect when given as monotherapy, but some of the drugs hold promise as an adjunct...... to chemotherapy. It should, however, be noted that most of the trials are based on few patients, and thus far the literature does not allow for a conclusion as to the role of biological treatment on cholangiocarcinoma. This situation calls for well-designed randomized trials, and international cooperation as well...

  1. 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

  2. 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.

  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. 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

  5. Evaluation of stability and simultaneous determination of fimasartan and amlodipine by a HPLC method in combination tablets

    Directory of Open Access Journals (Sweden)

    Hyeon Woo Moon

    2014-06-01

    Full Text Available A simple, rapid, accurate, precise and robust HPLC method was developed for the simultaneous determination of fimasartan and amlodipine in tablet dosage form. Furthermore, stability of active ingredients was evaluated under normal and stress conditions. The isocratic elution was accomplished by Nucleosil C18 column (250 mm × 4.6 mm, 5 μm at 40 °C. The mobile phase consisted of acetonitrile and 0.02 M monopotassium phosphate buffer (pH 2.2 in the ratio of 50:50 (v/v was eluted at 1.0 ml/min. The eluent was monitored by the UV detector for fimasartan and amlodipine at 237 nm for 8 min, detection time. The validation of HPLC method was carried out in accordance with the ICH guidelines.

  6. Combination of TREF, high-temperature HPLC, FTIR and HPer DSC for the comprehensive analysis of complex polypropylene copolymers.

    Science.gov (United States)

    Cheruthazhekatt, Sadiqali; Pijpers, Thijs F J; Mathot, Vincent B F; Pasch, Harald

    2013-11-01

    A novel, powerful analytical technique, preparative temperature rising elution fractionation (prep TREF)/high-temperature (HT)-HPLC/Fourier transform infrared spectroscopy (FTIR)/high-performance differential scanning calorimetry (HPer DSC)), has been introduced to study the correlation between the polymer chain microstructure and the thermal behaviour of various components in a complex impact polypropylene copolymer (IPC). For the comprehensive analysis of this complex material, in a first step, prep TREF is used to produce less complex but still heterogeneous fractions. These chemically heterogeneous fractions are completely separated by using a highly selective chromatographic separation method--high-temperature solvent gradient HPLC. The detailed structural and thermal analysis of the HPLC fractions was conducted by offline coupling of HT-HPLC with FTIR spectroscopy and a novel DSC method--HPer DSC. Three chemically different components were identified in the mid-elution temperature TREF fractions. For the first component, identified as isotactic polypropylene homopolymer by FTIR, the macromolecular chain length is found to be an important factor affecting the melting and crystallisation behaviour. The second component relates to ethylene-propylene copolymer molecules with varying ethylene monomer distributions and propylene tacticity distributions. For the polyethylene component (last eluting component in all semi-crystalline TREF fractions), it was found that branching produced defects in the long crystallisable ethylene sequences that affected the thermal properties. The different species exhibit distinctively different melting and crystallisation behaviour, as documented by HPer DSC. Using this novel approach of hyphenated techniques, the chain structure and melting and crystallisation behaviour of different components in a complex copolymer were investigated systematically.

  7. 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.

  8. 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...

  9. Chemical Characteristics Combined with Bioactivity for Comprehensive Evaluation of Tumuxiang Based on HPLC-DAD and Multivariate Statistical Methods

    Institute of Scientific and Technical Information of China (English)

    Xia Gao; Yu-Ling Ma; Pei Zhang; Xiao-Ping Zheng; Bo-Lu Sun; Fang-Di Hu

    2016-01-01

    Background: The dried roots of Inula helenium L. (IH) and Inula racemosa Hook f. (IR) are used commonly as folk medicine under the name of “tumuxiang (TMX)”. Phenolic acid compounds and their derivatives, as main active constituents in IH and IR, exhibit prominent anti-inflammation effect. Objective: To develop a holistic method based on chemical characteristic and anti-inflammation effect for systematically evaluating the quality of twenty-seven TMX samples (including 18 IH samples and 9 IR samples) from different origins. Methods: HPLC fingerprints data of AL (Aucklandia lappa Decne.) whose dried root was similar with HR was added for classification analysis. The HPLC fingerprints of twenty-seven TMX samples and four AL samples were evaluated using hierarchical clustering analysis (HCA) and principle component analysis (PCA). The spectrum-efficacy model between HPLC fingerprints and anti-inflammatory activities was investigated by principal component regression (PCR) and partial least squares(PLS). Results: All samples were successfully divided into three main clusters and peaks 7, 9, 11, 22, 24 and 26 had a primary contribution to classify these medicinal herbs. The results were in accord with the appraisal results of herbs. The spectrum-efficacy relationship results indicated that citric acid, quinic acid, caffeic acid-β-D-glucopyranoside, chlorogenic acid, caffeic acid, 1,3-O-dicaffeoyl quinic acid, tianshic acid and 3β-Hydroxypterondontic acid had main contribution to anti-inflammatory activities. Conclusion: This comprehensive strategy was successfully used for identification of IH, IR and AL, which provided a reliable and adequate theoretical basis for the bioactivity relevant quality standards and studying the material basis of anti-inflammatory effect of TMX.

  10. Development of HPLC and UV spectrophotometric methods for the determination of ascorbic acid using hydroxypropyl-{beta}-cyclodextrin and triethanolamine as photostabilizing agents

    Energy Technology Data Exchange (ETDEWEB)

    Garnero, Claudia [Departamento de Farmacia, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, Ciudad Universitaria, 5000 Cordoba (Argentina); Longhi, Marcela, E-mail: mrlcor@fcq.unc.edu.ar [Departamento de Farmacia, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, Ciudad Universitaria, 5000 Cordoba (Argentina)

    2010-02-05

    In this study, the effect of complex formation with triethanolamine (TEA) alone and in combination with hydroxypropyl-{beta}-cyclodextrin (HP-{beta}-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.

  11. 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.

  12. HPLC-ELSD Assay of Terpene Lactones in Combinations of the Shuxuening Injection%HPLC-ELSD法测定舒血宁注射液配伍溶液中内酯含量

    Institute of Scientific and Technical Information of China (English)

    王海涛; 冯志琼; 蔡海燕; 王永利

    2011-01-01

    Objective:To develop an HPLC-ELSD for determination of ginkgolide A,B and C in combinations of the Shuxuening injection.Results:There was good linear relation-ship between the absorption area value and the concentration in the ranges of 2-32μL for ginkgolide A (r=0.9998),for ginkgolide B (r=1)and for ginkgolide C (r=0.9996)respectively.The HPLC method showed good repeat ability.The average recoveries of ginkgolide A,B and C were 97.08%, (RSD=2.53%) ,102.06% (RSD=2.91%), 101.6% (RSD=2.25 %) respectively. Conclusion:The method is specific,sensitive,accurate.It has been effectively method for assay combinations of the Shuxuening injection.%目的:建立高效液相色谱一蒸发光散射检测法(HPLC—ELSD)同时测定舒血宁注射液中银杏内酯A、B、C的含量。结果:舒血宁注射液中银杏内酯A进样量在2~32μL范围内线性关系良好,r=0.9998;银杏内酯B进样量在2~32μL范围内线性关系良好,r=1;银杏内酯C进样量在2~32μL范围内线性关系良好,r=0.9996。方法重复性良好。银杏内酯A、B、C平均回收率分别为97.08%、102.06%、101.6%;RSD分别为2.53%、2.91%、2.25%。结论:该法专属性强,灵敏、准确,可作为舒血宁注射液配伍溶液中内酯含量的检测方法。

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Gas release-based prescreening combined with reversed-phase HPLC quantitation for efficient selection of high-γ-aminobutyric acid (GABA)-producing lactic acid bacteria.

    Science.gov (United States)

    Wu, Qinglong; Shah, Nagendra P

    2015-02-01

    High γ-aminobutyric acid (GABA)-producing lactobacilli are promising for the manufacture of GABA-rich foods and to synthesize GRAS (generally recognized as safe)-grade GABA. However, common chromatography-based screening is time-consuming and inefficient. In the present study, Korean kimchi was used as a model of lactic acid-based fermented foods, and a gas release-based prescreening of potential GABA producers was developed. The ability to produce GABA by potential GABA producers in de Man, Rogosa, and Sharpe medium supplemented with or without monosodium glutamate was further determined by HPLC. Based on the results, 9 isolates were regarded as high GABA producers, and were further genetically identified as Lactobacillus brevis based on the sequences of 16S rRNA gene. Gas release-based prescreening combined with reversed-phase HPLC confirmation was an efficient and cost-effective method to identify high-GABA-producing LAB, which could be good candidates for probiotics. The GABA that is naturally produced by these high-GABA-producing LAB could be used as a food additive.

  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. 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

  2. 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.

  3. 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

  4. Dual High-Resolution α-Glucosidase and Radical Scavenging Profiling Combined with HPLC-HRMS-SPE-NMR for Identification of Minor and Major Constituents Directly from the Crude Extract of Pueraria lobata

    DEFF Research Database (Denmark)

    Liu, Bingrui; Kongstad, Kenneth Thermann; Qinglei, Sun;

    2015-01-01

    The crude methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the crude extract without preceding purification was facilitated by combining chromatograms...

  5. 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)

  6. 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

  7. 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.

  8. In vitro potency and combination testing of antimicrobial agents against Neisseria gonorrhoeae.

    Science.gov (United States)

    Bharat, Amrita; Martin, Irene; Zhanel, George G; Mulvey, Michael R

    2016-03-01

    Antimicrobial resistant Neisseria gonorrhoeae is a major concern to public health due to decreased susceptibility to frontline antimicrobials. To find agents that are active against N. gonorrhoeae, we tested antimicrobials alone or in combination by Etest gradient strips. The potencies (as assessed by minimum inhibitory concentrations) of twenty-five antimicrobials were evaluated against nine reference strains of N. gonorrhoeae (WHO F, G, K, L, M, N, O, P and ATCC 49226). Potency was greatest for netilmicin, quinupristin-dalfopristin, ceftriaxone, ertapenem and piperacillin-tazobactam. Combinations of azithromycin, moxifloxacin, or gentamicin with ceftriaxone, doripenem, or aztreonam were tested against reference isolates and the fractional inhibitory concentration index (FICI) was calculated. All nine combinations resulted in indifference (>0.5 FICI ≤ 4). Combinations with FICI gonorrhoeae. These data on antimicrobials with higher potency and combinations that did not show antagonism can help to guide larger scale susceptibility studies for antimicrobial resistant N. gonorrhoeae.

  9. 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

  10. Discovery of wall teichoic acid inhibitors as potential anti-MRSA β-lactam combination agents.

    Science.gov (United States)

    Wang, Hao; Gill, Charles J; Lee, Sang H; Mann, Paul; Zuck, Paul; Meredith, Timothy C; Murgolo, Nicholas; She, Xinwei; Kales, Susan; Liang, Lianzhu; Liu, Jenny; Wu, Jin; Santa Maria, John; Su, Jing; Pan, Jianping; Hailey, Judy; Mcguinness, Debra; Tan, Christopher M; Flattery, Amy; Walker, Suzanne; Black, Todd; Roemer, Terry

    2013-02-21

    Innovative strategies are needed to combat drug resistance associated with methicillin-resistant Staphylococcus aureus (MRSA). Here, we investigate the potential of wall teichoic acid (WTA) biosynthesis inhibitors as combination agents to restore β-lactam efficacy against MRSA. Performing a whole-cell pathway-based screen, we identified a series of WTA inhibitors (WTAIs) targeting the WTA transporter protein, TarG. Whole-genome sequencing of WTAI-resistant isolates across two methicillin-resistant Staphylococci spp. revealed TarG as their common target, as well as a broad assortment of drug-resistant bypass mutants mapping to earlier steps of WTA biosynthesis. Extensive in vitro microbiological analysis and animal infection studies provide strong genetic and pharmacological evidence of the potential effectiveness of WTAIs as anti-MRSA β-lactam combination agents. This work also highlights the emerging role of whole-genome sequencing in antibiotic mode-of-action and resistance studies.

  11. 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...

  12. 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.

  13. 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.

  14. 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

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

    Science.gov (United States)

    Dasgupta, Tina; Haas-Kogan, Daphne A

    2013-01-01

    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 pediatric gliomas is being exploited with the use of specific targeted inhibitors. These agents are additionally being combined with XRT to increase the efficacy and duration of local control. In this review, we discuss novel agents targeting three different pathways in gliomas, and their potential combination with XRT. BRAF is a serine/threonine kinase in the RAS/RAF/MAPK kinase pathway, which is integral to cellular division, survival, and metabolism. Two-thirds of pilocytic astrocytomas, a low-grade pediatric glioma, contain a translocation within the BRAF gene called KIAA1549:BRAF that causes an overactivation of the MEK/MAPK signaling cascade. In vitro and in vivo data support the use of MEK or mammalian target of rapamycin (mTOR) inhibitors in low-grade gliomas expressing this translocation. Additionally, 15-20% of high-grade pediatric gliomas express BRAF V600E, an activating mutation of the BRAF gene. Pre-clinical in vivo and in vitro data in BRAF V600E gliomas demonstrate dramatic cooperation between XRT and small molecule inhibitors of BRAF V600E. Another major signaling cascade that plays a role in pediatric glioma pathogenesis is the PI3-kinase (PI3K)/mTOR pathway, known to be upregulated in the majority of high- and low-grade pediatric gliomas. Dual PI3K/mTOR inhibitors are in clinical trials for adult high-grade gliomas and are poised to enter studies of pediatric tumors. Finally, many brain tumors express potent stimulators of angiogenesis that render them refractory to treatment. An analog of thalidomide, CC-5103 increases the secretion of critical cytokines of the tumor

  17. 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

  18. 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.

  19. Validation of RP-HPLC method and stress degradation for the combination of metformin HCl, atorvastatin calcium and glimepiride: application to nanoparticles.

    Science.gov (United States)

    Gite, Sandip; Patravale, Vandana

    2015-01-01

    A stability-indicating high-performance liquid chromatography (HPLC) procedure was developed for the determination of metformin HCl (MTH), atorvastatin calcium (AC) and glimepiride (GP) in combination and their main degradation products. The separation and quantization were achieved on a 5-µm Qualisil gold, C18 column (4.6 mm × 250 mm). The mobile phase selected was phosphate buffer (pH 2.9)-organic phase in proportion of 70:30. Organic phase consisted of methanol-acetonitrile (90:10) at a flow rate of 1 mL/min and detection of analytes was carried out at 230 nm. The method exhibited good linearity over the range of 10-60 µg/mL for MTH, 2-20 µg/mL for AC and 5-30 µg/mL for GP. Square of the correlation coefficients was found to be >0.999. Various stress degradation studies were carried out in combination as per International Conference of Harmonization (ICH) guidelines for 4 h. The recovery and precision were determined in terms of intraday and interday precisions and expressed as relative standard deviations. These were <1 and <2%, respectively. Finally, the applicability of the method was evaluated in nanoparticle analysis of MTH, AC and GP as well as in stability studies of nanoformulation. PMID:26071607

  20. 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.

  1. 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

  2. Renal cell carcinoma: review of novel single-agent therapeutics and combination regimens.

    Science.gov (United States)

    Amato, R J

    2005-01-01

    A search of the Medline database and ASCO 2003 conference proceedings was conducted to identify clinical trials currently underway using single-agent therapy for renal cell carcinoma (RCC). Combination trials were identified using the ASCO 2003 conference proceedings. Fourteen single-agent therapies employing different mechanisms of action were identified in the published literature: imatinib mesylate (Gleevec); bevacizumab (Avastin); thalidomide (Thalomid); gefitinib (ZD1839) (Iressa); cetuximab (IMC-C225) (Erbitux); bortezomib (PS-341) (Velcade); HSPPC-96 (Oncophage); BAY 59-8862; ABT-510; G250; CCI-779; SU5416; PTK/ZK; and ABX-EGF. Six distinct fields of clinical research have emerged: monoclonal antibodies, small molecules, vaccines, second-generation taxanes, nonapeptides and immunomodulators. Five combination regimens, primarily biological response modifiers (interleukin-2 or interferon-alpha), chemotherapy- or thalidomide-based, were identified. All therapies demonstrated acceptable toxicity profiles. Clinical benefit was assessed based on each study's reported criteria: antitumor response (regression or stability) ranged from 5% to 71%. In the past several years, significant advances in the underlying biological mechanisms of RCC, particularly the role of tumor angiogenesis, have permitted the design of molecularly targeted therapeutics. Based on preliminary and limited studies, combination therapies offer the greatest clinical benefit in the management of this malignancy, although additional basic research is still warranted.

  3. 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...

  4. 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

  5. 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

  6. 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

  7. 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......Candida albicans, one of the pathogenic Candida species, causes high mortality rate in immunocompromised and high-risk surgical patients. In the last decade, only one new class of antifungal drug echinocandin was applied. The increased therapy failures, such as the one caused by multi......-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....

  8. Analysis of 26 amino acids in human plasma by HPLC using AQC as derivatizing agent and its application in metabolic laboratory.

    Science.gov (United States)

    Sharma, Gaurav; Attri, Savita Verma; Behra, Bijaylaxmi; Bhisikar, Swapnil; Kumar, Praveen; Tageja, Minni; Sharda, Sheetal; Singhi, Pratibha; Singhi, Sunit

    2014-05-01

    The present study reports the simultaneous analysis of 26 physiological amino acids in plasma along with total cysteine and homocysteine by high-performance liquid chromatography (HPLC) employing 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) as precolumn derivatizing reagent. Separations were carried out using Lichrospher 100 RP-18e (5 μm) 250 × 4.0 mm column connected to 100 CN 4.0 × 4.0 mm guard column on a quaternary HPLC system and run time was 53 min. Linearity of the peak areas for different concentrations ranging from 2.5 to 100 pmol/μL of individual amino acids was determined. A good linearity (R (2) > 0.998) was achieved in the standard mixture for each amino acid. Recovery of amino acids incorporated at the time of derivatization ranged from 95 to 106 %. Using this method we have established the normative data of amino acids in plasma, the profile being comparable to the range reported in literature and identified cases of classical homocystinuria, cobalamin defect/deficiency, non-ketotic hyperglycinemia, hyperprolinemia, ketotic hyperglycinemia, urea cycle defect and maple syrup urine disease.

  9. 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.

  10. High-Resolution α-Glucosidase Inhibition Profiling Combined with HPLC-HRMS-SPE-NMR for Identification of Antidiabetic Compounds in Eremanthus crotonoides (Asteraceae).

    Science.gov (United States)

    Silva, Eder Lana E; Lobo, Jonathas Felipe Revoredo; Vinther, Joachim Møllesøe; Borges, Ricardo Moreira; Staerk, Dan

    2016-06-16

    α-Glucosidase inhibitors decrease the cleavage- and absorption rate of monosaccharides from complex dietary carbohydrates, and represent therefore an important class of drugs for management of type 2 diabetes. In this study, a defatted ethyl acetate extract of Eremanthus crotonoides leaves with an inhibitory concentration (IC50) of 34.5 μg/mL towards α-glucosidase was investigated by high-resolution α-glucosidase inhibition profiling combined with HPLC-HRMS-SPE-NMR. This led to identification of six α-glucosidase inhibitors, namely quercetin (16), trans-tiliroside (17), luteolin (19), quercetin-3-methyl ether (20), 3,5-di-O-caffeoylquinic acid n-butyl ester (26) and 4,5-di-O-caffeoylquinic acid n-butyl ester (29). In addition, nineteen other metabolites were identified. The most active compounds were the two regioisomeric di-O-caffeoylquinic acid derivatives 26 and 29, with IC50 values of 5.93 and 5.20 μM, respectively. This is the first report of the α-glucosidase inhibitory activity of compounds 20, 26, and 29, and the findings support the important role of Eremanthus species as novel sources of new drugs and/or herbal remedies for treatment of type 2 diabetes.

  11. High-Resolution α-Glucosidase Inhibition Profiling Combined with HPLC-HRMS-SPE-NMR for Identification of Antidiabetic Compounds in Eremanthus crotonoides (Asteraceae

    Directory of Open Access Journals (Sweden)

    Eder Lana e Silva

    2016-06-01

    Full Text Available α-Glucosidase inhibitors decrease the cleavage- and absorption rate of monosaccharides from complex dietary carbohydrates, and represent therefore an important class of drugs for management of type 2 diabetes. In this study, a defatted ethyl acetate extract of Eremanthus crotonoides leaves with an inhibitory concentration (IC50 of 34.5 μg/mL towards α-glucosidase was investigated by high-resolution α-glucosidase inhibition profiling combined with HPLC-HRMS-SPE-NMR. This led to identification of six α-glucosidase inhibitors, namely quercetin (16, trans-tiliroside (17, luteolin (19, quercetin-3-methyl ether (20, 3,5-di-O-caffeoylquinic acid n-butyl ester (26 and 4,5-di-O-caffeoylquinic acid n-butyl ester (29. In addition, nineteen other metabolites were identified. The most active compounds were the two regioisomeric di-O-caffeoylquinic acid derivatives 26 and 29, with IC50 values of 5.93 and 5.20 μM, respectively. This is the first report of the α-glucosidase inhibitory activity of compounds 20, 26, and 29, and the findings support the important role of Eremanthus species as novel sources of new drugs and/or herbal remedies for treatment of type 2 diabetes.

  12. 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.

  13. 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

  14. Tunable release of chemotherapeutic and vascular disrupting agents from injectable fiber fragments potentiates combination chemotherapy.

    Science.gov (United States)

    Luo, Xiaoming; Xu, Guisen; Wei, Jiaojun; Chen, Maohua; Zhang, Hong; Li, Xiaohong

    2016-06-15

    Cancer progression and metastasis relies much on vasculature networks in tumor microenvironment, and the combination treatment with chemotherapeutic drugs and vascular disrupting agents represents apparent clinical benefits. In the current study, fiber fragments with loadings of hydroxycamptothecin (HCPT) or combretastatin A-4 (CA4) were proposed for tumor inhibition and blood vessel disruption after local administration in tumors. To address challenges in balancing the disruption of tumor vessels and intratumoral uptake of chemotherapeutic agents, this study is focus on release tuning of HCPT and CA4 from the fiber fragment mixtures. Hydroxypropyl-β-cyclodextrin (HPCD) was blended at ratios from 0 to 10% into CA4-loaded fiber fragments (Fc) to modulate CA4 release durations from 0.5 to 24days, and HCPT-loaded fiber fragments (Fh) indicated a sustained release for over 35days. In vitro cytotoxicity tests indicated a sequential inhibition on the endothelial and tumor cell growth, and the growth inhibition of tumor cells was more significant after treatment with mixtures of Fh and Fc containing 2% HPCD (Fc2) than that of other mixtures. In an orthotopic breast tumor model, compared with those of free CA4, or Fc with a fast or slow release of CA4, Fh/Fc mixtures with CA4 release durations from 2 to 12days indicated a lower tumor growth rate, a prolonged animal survival, a lower vessel density in tumors, and a less significant tumor metastasis. In addition, the tumor cell proliferation rate, hypoxia-inducible factor-1α expression within tumors, and the number of surface metastatic nodules in lungs were significantly lower after treatment with Fh/Fc2 mixtures with a CA4 release duration of 5days than those of other mixtures. It demonstrates the advantages of fiber fragment mixtures in independently modulating the release of multiple drugs and the essential role of release tuning of chemotherapeutic drugs and vascular disrupting agents in improving the therapeutic

  15. Advances in drug deliver y system for platinum agents based combination therapy

    Institute of Scientific and Technical Information of China (English)

    Xiang Kang; Hai-Hua Xiao; Hai-Qin Song; Xia-Bin Jing; Le-San Yan; Ruo-Gu Qi

    2015-01-01

    Platinum-based anticancer agents are widely used as first-line drugs in cancer chemotherapy for various solid tumors. However, great side effects and occurrence of resistance remain as the major drawbacks for almost all the platinum drugs developed. To conquer these problems, new strategies should be adopted for platinum drug based chemotherapy. Modern nanotechnology has been widely employed in the delivery of various therapeutics and diagnostic. It provides the possibility of targeted delivery of a certain anticancer drug to the tumor site, which could minimize toxicity and optimize the drug effcacy. Here, in this review, we focused on the recent progress in polymer based drug delivery systems for platinum-based combination therapy.

  16. 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

  17. 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.

  18. 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

  19. 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。

  20. Synergistic Anticancer Effect of Tocotrienol Combined with Chemotherapeutic Agents or Dietary Components: A Review

    Directory of Open Access Journals (Sweden)

    Takahiro Eitsuka

    2016-09-01

    Full Text Available Tocotrienol (T3, unsaturated vitamin E, is gaining a lot of attention owing to its potent anticancer effect, since its efficacy is much greater than that of tocopherol (Toc. Various factors are known to be involved in such antitumor action, including cell cycle arrest, apoptosis induction, antiangiogenesis, anti-metastasis, nuclear factor-κB suppression, and telomerase inhibition. Owing to a difference in the affinity of T3 and Toc for the α-tocopherol transfer protein, the bioavailability of orally ingested T3 is lower than that of Toc. Furthermore, cellular uptake of T3 is interrupted by coadministration of α-Toc in vitro and in vivo. Based on this, several studies are in progress to screen for molecules that can synergize with T3 in order to augment its potency. Combinations of T3 with chemotherapeutic drugs (e.g., statins, celecoxib, and gefitinib or dietary components (e.g., polyphenols, sesamin, and ferulic acid exhibit synergistic actions on cancer cell growth and signaling pathways. In this review, we summarize the current status of synergistic effects of T3 and an array of agents on cancer cells, and discuss their molecular mechanisms of action. These combination strategies would encourage further investigation and application in cancer prevention and therapy.

  1. 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.

  2. 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...

  3. 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

  4. 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

  5. HPLC method development and validation of cytotoxic agent phenyl-heptatriyne in Bidens pilosa with ultrasonic-assisted cloud point extraction and preconcentration.

    Science.gov (United States)

    Trivedi, Priyanka; Kumar, Jonnala Kotesh; Negi, Arvind Singh; Shanker, Karuna

    2011-06-01

    Extraction and pre-concentration of a bioactive marker compound, phenyl-1,3,5-heptatriyne from Bidens pilosa, prior to HPLC has been demonstrated using both organic and ecofriendly solvents. Non-ionic surfactants, viz. Triton X-100, Triton X-114 and Genapol X-80, were used for extraction. No back-extraction or liquid chromatographic steps were required to remove the target phytochemical from the surfactant-rich extractant phase. The optimized cloud point extraction procedure has been shown to be a potentially useful methodology for the preconcentration of the target analyte, with a preconcentration factor of 4-99. Moreover, the method is simple, sensitive, rapid and consumes lesser solvent than traditional methods. An isocratic chromatographic separation and quantitation was accomplished on a C(18) column with acetonitrile-acidified aqueous as mobile phase at a flow rate of 1.0 mL/min, UV detection at 254 nm and specificity with photo diode-array detector (PDA) and MS. Under the optimum experimental conditions recovery was satisfactory (99.18-100.33%) without interference from the surfactant. The method seems to be reliable with intraday precision and interday precision below 2.0%. Good linearity was obtained in the working range from 7.5 to 30 µg/mL with correlation coefficient >0.99. The limits of detection and quantitation were 1.84 and 6.13 µg/mL, respectively. The method was validated following international guidelines and successfully applied for quantitative assays of cytotoxic compound phenyl-1,3,5-heptatriyne in Bidens pilosa.

  6. A nitric oxide-releasing heparin conjugate for delivery of a combined antiplatelet/anticoagulant agent.

    Science.gov (United States)

    Suchyta, Dakota J; Handa, Hitesh; Meyerhoff, Mark E

    2014-02-01

    Heparin is a widely used anticoagulant due to its ability to inhibit key components in the coagulation cascade such as Factor Xa and thrombin (Factor IIa). Its potential to preferentially bind to antithrombin (ATIII) results in a conformational change and activation that leads to the prevention of fibrin formation from fibrinogen and ultimately obstructs a hemostatic plug from forming. Nitric oxide (NO) exhibits potent antiplatelet activity attributed to its capacity to increase the amount of cyclic guanosine monophosphate (cGMP) within platelets, which decreases the Ca(2+) concentration required for platelet activation. Currently there is no single agent that combines the functions of both antiplatelet and anticoagulant (anti-Xa and anti-IIa) activities to effectively block both the extrinsic and the intrinsic coagulation pathways. The research reported herein demonstrates the ability to combine the physiological capabilities of both heparin and NO into one functional compound via use of a spermine derivative of heparin, thus enabling formation of a novel diazeniumdiolate (NONOate). The heparin-spermine NONOate has a half-life of 85 min at 25 °C (pH 7.4). The heparin backbone of the conjugate maintains its anticoagulant activity as demonstrated via an anti-Xa assay, providing an anticoagulant conversion of 3.6 μg/mL of the heparin-spermine-NONO conjugate being equivalent to 2.5 μg/mL (0.50 IU/mL) of underivatized heparin in terms of anti-Xa activity. Using standard platelet aggregometry, it is shown that the functionality of the NO release portion of the heparin conjugate prevents (nearly 100%) platelet aggregation in the presence of adenosine diphosphate (ADP, platelet agonist). PMID:24423090

  7. HPLC-MS and GC-MS analyses combined with orthogonal partial least squares to identify cytotoxic constituents from turmeric (Curcuma longa L.).

    Science.gov (United States)

    Jiang, Jianlan; Zhang, Huan; Li, Zidan; Zhang, Xiaohang; Su, Xin; Li, Yan; Qiao, Bin; Yuan, Yingjin

    2013-08-01

    We investigated the fingerprints of 48 batches of turmeric total extracts (TTE) by HPLC-MS-MS and GC-MS analyses and 43 characteristic peaks (22 constituents from HPLC-MS-MS; 21 from GC-MS) were analyzed qualitatively and quantitatively. An MTT {3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide} assay was implemented to measure the cytotoxicity of the TTE against HeLa cells. Then we utilized orthogonal partial least squares analysis, which correlated the chemical composition of the TTE to its cytotoxic activity, to identify potential cytotoxic constituents from turmeric. The result showed that 19 constituents contributed significantly to the cytotoxicity. The obtained result was verified by canonical correlation analysis. Comparison with previous reports also indicated some interaction between the curcuminoids and sesquiterpenoids in turmeric.

  8. 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.

  9. 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

  10. 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%.

  11. 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

  12. 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

  13. 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.

  14. 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...

  15. 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

  16. Content Determination of Cocaine Hydrochloride in Paraformaldehyde Dental Pulp Devitalizing Agent by HPLC%HPLC法测定多聚甲醛牙髓失活剂中盐酸可卡因含量

    Institute of Scientific and Technical Information of China (English)

    林瑶; 杨敏茹; 郭飞燕; 王荣; 王晓娟; 顾宜

    2011-01-01

    OBJECTIVE: To establish a method for the content determination of cocaine hydrochloride in Paraformaldehyde dental pulp devitalizing agent. METHODS: HPLC method was adopted. The determination was performed on Diamonsil-C18 column with mobile phase consisted of methanol -0.5% triethylamine (pH adjusted to 4.5 using phosphoric acid) (30 :70) at flow rate of 1.0 mL·min-1. The detection wavelength was set at 235 nm and the column temperature was 25℃. The sample size was 10 μL. RESULTS: The linear range of cocaine hydrochloride was 16.208-129.664 μg·mL-1 (r=0.999 7) ,the average recovery was 95.12% (RSD=1.15%). CONCLUSION: The method is simple, sensitive, rapid, accurate and reliable.%目的:建立测定多聚甲醛牙髓失活剂中盐酸可卡因含量的方法.方法:采用高效液相色谱法.色谱柱为Diamonsil C18,流动相为甲醇-0.5%三乙胺溶液(磷酸调pH值至4.5)=30∶70,检测波长为235 nm,流速为1.0mL·min-1,柱温为25℃,进样量为10 μL.结果:盐酸可卡因检测浓度线性范围为16.208~129.664 μg·mL-1(r=0.999 7);平均加样回收率为95.12%,RSD=1.15%.结论:所建立的方法简便、灵敏、快速,结果准确、可靠.

  17. Use of albendazole sulfoxide, albendazole sulfone, and combined solutions as scolicidal agents on hydatid cysts ( in vitro study)

    Institute of Scientific and Technical Information of China (English)

    Gokhan Adas; Soykan Arikan; Ozgur Kemik; Ali Oner; Nilgun Sahip; Oguzhan Karatepe

    2009-01-01

    AIM: To establish which scolicidal agents are superior and more suitable for regular use.METHODS: Echinococcus granulosus protoscoleces were obtained from 25 patients with liver hydatid cysts. Various concentrations of albendazole sulfone,albendazole sulfoxide, and albendazole sulfone and albendazole sulfoxide mixed together in concentrations of 50 μg/mL, and H2O2 in a concentration of 4%, NaCl 20%, and 1.5% cetrimide-0.15% chlorhexidine (10% Savlon-Turkey) were used to determine the scolicidal effects. Albendazole (ABZ) derivatives and other scolicidal agents were applied to a minimum of 100 scoleces for 5 and 10 min. The degree of viability was calculated according to the number of living scolices per field from a total of 100 scolices observed under the microscope.RESULTS: After 5 min, ABZ sulfone was 97.3% effective, ABZ sulfoxide was 98.4% effective, and the combined solution was 98.6% effective. When sulfone, sulfoxide and the combined solutions were compared,the combined solution seemed more effective than sulfone. However, there was no difference when the combined solution was compared with sulfoxide. After 10 min, hypertonic salt water, sulfone, sulfoxide, and the combined solution compared to other solutions looked more effective and this was statistically significant on an advanced level. When sulfone,sulfoxide, and the combined solutions were compared with each other, the combined solution appeared more effective than sulfone. When the combined solution was compared with sulfoxide, there was no difference.CONCLUSION: Despite being active, ABZ metabolites did not provide a marked advantage over 20% hypertonic saline. According to these results, we think creating a newly improved and more active preparation is necessary for hydatid cyst treatment.

  18. Cramer’s Rule, Tri Linear Regression and RP-HPLC Method Development for the Estimation of Combined Dosage Form of Anti Diabetic Drugs

    Directory of Open Access Journals (Sweden)

    Bhauvaneswara Rao C.

    2016-05-01

    Full Text Available In this study two simple, rapid, precise and accurate spectrophotometric methods and one RP – HPLC method were developed and validated for the estimation of Atorvastatin calcium, Metformin hydrochloride and Glimepiride in pure form and in tablet dosage form. Different aliquots of Atorvastatin calcium, Metformin hydrochloride and Glimepiride in methanol were prepared in the concentration range of 4 – 24, 3 – 15 and 1 - 5 µg/ml respectively. The percentage label claim present in tablet formulation was found to be 98.46 ± 1.2781, 102.29 ± 1.1598 and 99.67 ± 1.1832 % for Atorvastatin calcium, Metformin hydrochloride and Glimepiride, respectively. The accuracy of the method was confirmed by recovery studies. The % RSD value, percentage recovery for Atorvastatin calcium, Metformin hydrochloride and Glimepiride were calculated.

  19. 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)

  20. 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)

  1. Determination of the blood concentration of cyclosporine A alone and in combination with fluconazole by HPLC/MS%HPLC/MS测定环孢素A单用及联用氟康唑的血药浓度

    Institute of Scientific and Technical Information of China (English)

    易林高; 吴明钗; 黄鹏; 陈晓孩; 陆日鸣

    2016-01-01

    Objective:To establish a mass spectrometry method for determination of blood concentration of cyclosporine A (CsA), and determine the blood concentration of cyclosporine A alone and in combination with lfuconazole.Methods:The blood concentration of cyclosporine A in rats was detected and compared when cyclosporine alone and combined with lfuconazole by using liquid chromatography-mass spectrometry. Chromatographic column Agilent Zorbax SB-C18 was used. Column temperature was 50℃. Mobile phase was acetonitrile-0.1% formic acid. Flow rate was 0.5 mL·min-1. Mass spectrometry condition was as follows: ESI (electrospray ion source) was used, positive ion detection was used, atomizing gas pressure was set to 20 psi.Results:The linear relationship of CsA was good in the range of 100 – 20 000 ng·mL-1 (r = 0.999 6). Intra-day RSD and inter-day RSD were less than 5%. The average extraction recovery was 90%. The average blood trough concentration of CsA when CsA combined with lfuconazole was higher (by 178.0%) than just cyclosporine alone in ifve days, and the peak concentration in combined utilization was higher (by 161.3%) than that of alone use.Conclusion: The method is simple, specific, accurate and high sensitivity, which can also be used for the determination of CsA blood concentration and pharmacokinetics study. Patients who are using CsA and lfuconazole will obviously have high blood concentrations of CsA, should reduce the dosage of CsA, and monitor the blood concentration.%目的:建立质谱法测定环孢素A(CsA)的血药浓度,并用其测定CsA单/联用氟康唑的血药浓度。方法:采用液质联用法测定单/联用氟康唑时CsA的血药浓度,色谱柱:Agilent Zorbax SB-C18柱,柱温50℃,流动相为乙腈-0.1%甲酸,流速0.5 mL·min-1;质谱条件:ESI(电喷雾离子源),正离子检测,雾化气压力设为20 psi。结果:CsA在100~20000 ng·mL-1内线性关系良好(r =0.9996

  2. Event-triggered nonlinear consensus in directed multi-agent systems with combinational state measurements

    Science.gov (United States)

    Li, Huaqing; Chen, Guo; Xiao, Li

    2016-10-01

    Event-triggered sampling control is motivated by the applications of embedded microprocessors equipped in the agents with limited computation and storage resources. This paper studied global consensus in multi-agent systems with inherent nonlinear dynamics on general directed networks using decentralised event-triggered strategy. For each agent, the controller updates are event-based and only triggered at its own event times by only utilising the locally current sampling data. A high-performance sampling event that only needs local neighbours' states at their own discrete time instants is presented. Furthermore, we introduce two kinds of general algebraic connectivity for strongly connected networks and strongly connected components of the directed network containing a spanning tree so as to describe the system's ability for reaching consensus. A detailed theoretical analysis on consensus is performed and two criteria are derived by virtue of algebraic graph theory, matrix theory and Lyapunov control approach. It is shown that the Zeno behaviour of triggering time sequence is excluded during the system's whole working process. A numerical simulation is given to show the effectiveness of the theoretical results.

  3. 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

  4. 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

  5. Fluoroscopy guided instillation therapy in chyluria using combination of povidone iodine with contrast agent: is a single instillation sufficient?

    Directory of Open Access Journals (Sweden)

    Gyanendra Sharma

    2008-06-01

    Full Text Available PURPOSE: To evaluate the safety and efficacy of a single instillation in a combination of povidone iodine with contrast agent under fluoroscopy guidance for the treatment of chyluria. MATERIALS AND METHODS: From December 1999 to July 2006 a total of 40 patients with chyluria were treated by renal pelvic instillation therapy (RPIS. The sclerosing solution was prepared using povidone iodine with contrast agent diluted with sterile water in a ratio of 1:1:3. It was instilled on the side having chylous efflux using a bulb tip ureteric catheter. Unilateral instillation was done in 26 cases, 10 on the right side and 16 on left. Fourteen patients had bilateral chylous efflux and RPIS was performed on both sides in the same session. Fluoroscopy was used to evaluate the complete filling of the pelvic calyceal system. The sclerosing solution was kept in the system for 5 minutes and the ureteric catheter was then withdrawn. RESULTS: Immediate clearance was observed in 39 patients. Recurrence occurred in five patients. They were treated again using the same procedure with satisfactory results. The longest follow-up was five years and the shortest five months. CONCLUSION: RPIS of chyluria using a single instillation a combination of povidone iodine with contrast agent is safe and effective. Use of fluoroscopy helps to determine the exact amount of sclerosing solution required to completely fill the system and therefore overfilling is avoided. Moreover, the complications, which arise due to pyelointerstitial backflow, are prevented.

  6. 化妆品中5种禁用着色剂的高效液相色谱检测及质谱确证%Determination of Five Prohibited Coloring Agents in Cosmetics by HPLC and Their Verification by HPLC-MS/MS

    Institute of Scientific and Technical Information of China (English)

    王烨; 马强; 白桦; 王超; 丁岚; 孟宪双; 陈云霞

    2012-01-01

    An HPLC method was developed for the determination of acid yellow 36, pigment red 53 : 1, pigment orange 5, sudan Ⅱ and sudan Ⅳ in cosmetics. The extraction conditions of five prohibited coloring agents in cosmetic samples, including wax, powder and liquid, were investigated. Using tetrabutylammonium hydroxide as an ion-pair reagent, the optimum chromatographic conditions of the prohibited coloring agents were investigated. The optimal conditions were as the follows: stationary phase; Hypersil C18(4. 6 mm ×250 mm, 5 μm) , mobile phase: acetonitrile(A) -0.01 mol/L tetrabutylammonium hydroxide and 0.01 mol/L citric acid(pH 8.2, B) , flow rate; 1.0 mL/ min, column temperature; 30 ℃ and detection wavelengths; 416, 484, 514 nm. The calibration curves of five prohibited coloring agents showed good linearities in the range of 0. 2 - 50 mg/L with correlation coefficients more than 0. 999 and LODs(S/Af =3) of 0. 2 -0. 5 mg/L. The five prohibited coloring agents were verified by HPLC — MS/MS. At three spiked levels, the average recoveries were between 85% and 102% , with relative standard deviations of 0. 5% - 3. 6% . The method was accurate, simple and rapid, and could be used to determine acid yellow 36, pigment red 53 : 1, pigment orange 5, sudan Ⅱ and sudan Ⅳ in cosmetics.%建立了高效液相色谱测定化妆品中酸性黄36、颜料红53∶1、颜料橙5、苏丹红Ⅱ和苏丹红Ⅳ5种禁用着色剂的分析方法.考察了着色剂使用率较高的蜡质类、固体粉类和液体类基质化妆品中着色剂的最佳提取条件.在流动相中添加离子对试剂四丁基氢氧化铵调节着色剂的色谱保留,使之达到完全分离,最佳色谱条件为:以依利特Hypersil C18(4.6 mm×250 mm,5μm)色谱柱分离,流动相为乙腈-0.01 mol/L四丁基氢氧化铵/0.01 mol/L柠檬酸缓冲溶液(pH 8.2),梯度洗脱,流速1.0 mL/min,柱温30℃,检测波长416、484、514 nm.考察了蜡质类、固体粉类和液体类等不同基质化

  7. 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

  8. 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.

  9. 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

  10. 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...

  11. 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 ...

  12. 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

  13. 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

  14. 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.

  15. Three-phase hollow-fiber liquid-phase microextraction combined with HPLC-UV for the determination of isothiazolinone biocides in adhesives used for food packaging materials.

    Science.gov (United States)

    Rosero-Moreano, Milton; Canellas, Elena; Nerín, Cristina

    2014-02-01

    The present study deals with the development of a liquid microextraction procedure for enhancing the sensitivity of the determination of 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one in adhesives. The procedure involves a three-phase hollow-fiber liquid-phase microextraction using a semipermeable polypropylene membrane, which contained 1-octanol as the organic phase in the pores of the membrane. The donor and acceptor phases are aqueous acidic and alkaline media, respectively, and the final liquid phase (acceptor) is analyzed by HPLC coupled with diode array detection. The most appropriate conditions were extraction time 20 min, stirring speed 1400 rpm, extraction temperature 50°C. The quantification limits of the method were 0.123 and 0.490 μg/g for 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one, respectively. Three different adhesive samples were successfully analyzed. The procedure was compared to direct analysis using ultra high pressure liquid chromatography coupled with TOF-MS, where the identification of the compounds and the quantification values were confirmed.

  16. 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.

  17. 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

  18. Determination of bisphenol A in thermal printing papers treated by alkaline aqueous solution using the combination of single-drop microextraction and HPLC.

    Science.gov (United States)

    Gao, Leihong; Zou, Jing; Liu, Haihong; Zeng, Jingbin; Wang, Yiru; Chen, Xi

    2013-04-01

    A method for the quantitative determination of bisphenol A in thermal printing paper was developed and validated. Bisphenol A was extracted from the paper samples using 2% NaOH solution, then the extracted analyte was enriched using single-drop microextraction followed by HPLC analysis. Several parameters relating to the single-drop microextraction efficiency including extraction solvent, extraction temperature and time, stirring rate, and pH of donor phase were studied and optimized. Spiked recovery of bisphenol A at 20 and 5 mg/g was found to be 95.8 and 108%, and the method detection limit and method quantification limit was 0.03 and 0.01 mg/g, respectively. Under the optimized conditions, the proposed method was applied to the determination of bisphenol A in seven types of thermal printing paper samples, and the concentration of bisphenol A was found in the range of 0.53-20.9 mg/g. The considerably minimum usage of organic solvents (5 μL 1-octanol) and high enrichment factor (189-197) in the sample preparation are the two highlighted advantages in comparison with previously published works.

  19. 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

  20. 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

  1. 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...

  2. 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

  3. Pathophysiologic effects of vascular-targeting agents and the implications for combination with conventional therapies

    DEFF Research Database (Denmark)

    Horsman, Michael Robert; Siemann, D.W.

    2006-01-01

    successful in the clinic they will need to be combined with more conventional therapies. However, by affecting the tumor vascular supply, these VTAs should induce pathophysiologic changes in variables, such as blood flow, pH, and oxygenation. Such changes could have negative or positive influences......A functional vascular supply is critical for the continued growth and development of solid tumors. It also plays a major role in metastatic spread of tumor cells. This importance has led to the concept of targeting the vasculature of the tumor as a form of cancer therapy. Two major types...... on the tumor response to more conventional therapies. This review aims to discuss the pathophysiologic changes induced by VTAs and the implications of these effects on the potential use of VTAs in combined modality therapy....

  4. 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...

  5. 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

  6. 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

    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...... (n = 153) received weekly epirubicin (E) 20 mg/m2 until progression or until the cumulative dose of 1,000 mg/m2, followed by mitomycin (M) 8 mg/m2 every 4 weeks, and those in the combination chemotherapy arm (n = 150) were first given cyclophosphamide 500 mg/m2, E 60 mg/m2, and fluorouracil 500 mg/m2...... three times per week (CEF) followed by M 8 mg/m2 plus vinblastine (V) 6 mg/m2 every 4 weeks. Exclusion criteria included age greater than 70 years, World Health Organization (WHO) performance status greater than 2, prior chemotherapy for metastatic disease, and presence of liver metastases in patients...

  7. 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.

  8. 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.

  9. Sporothrix schenckii COMPLEX: SUSCEPTIBILITIES TO COMBINED ANTIFUNGAL AGENTS AND CHARACTERIZATION OF ENZYMATIC PROFILES

    Directory of Open Access Journals (Sweden)

    Daniele Carvalho OLIVEIRA

    2015-08-01

    Full Text Available SUMMARY Sporothrix schenckiiwas reclassified as a complex encompassing six cryptic species, which calls for the reassessment of clinical and epidemiological data of these new species. We evaluated the susceptibility of Sporothrix albicans (n = 1 , S. brasiliensis (n = 6 , S. globosa (n = 1, S. mexicana(n = 1 and S. schenckii(n = 36 to terbinafine (TRB alone and in combination with itraconazole (ITZ, ketoconazole (KTZ, and voriconazole (VRZ by a checkerboard microdilution method and determined the enzymatic profile of these species with the API-ZYM kit. Most interactions were additive (27.5%, 32.5% and 5% or indifferent (70%, 50% and 52.5% for TRB+KTZ, TRB+ITZ and TRB+VRZ, respectively. Antagonisms were observed in 42.5% of isolates for the TRB+VRZ combination. Based on enzymatic profiling, the Sporothrix schenckii strains were categorized into 14 biotypes. Leucine arylamidase (LA activity was observed only for S. albicans and S. mexicana. The species S. globosaand S. mexicanawere the only species without β-glucosidase (GS activity. Our results may contribute to a better understanding of virulence and resistance among species of the genus Sporothrixin further studies.

  10. Sporothrix schenckii COMPLEX: SUSCEPTIBILITIES TO COMBINED ANTIFUNGAL AGENTS AND CHARACTERIZATION OF ENZYMATIC PROFILES

    Science.gov (United States)

    OLIVEIRA, Daniele Carvalho; de LORETO, Érico Silva; MARIO, Débora Alves Nunes; LOPES, Paulo G. Markus; NEVES, Louise Vignolles; da ROCHA, Marta Pires; SANTURIO, Janio Morais; ALVES, Sydney Hartz

    2015-01-01

    SUMMARY Sporothrix schenckiiwas reclassified as a complex encompassing six cryptic species, which calls for the reassessment of clinical and epidemiological data of these new species. We evaluated the susceptibility of Sporothrix albicans (n = 1) , S. brasiliensis (n = 6) , S. globosa (n = 1), S. mexicana(n = 1) and S. schenckii(n = 36) to terbinafine (TRB) alone and in combination with itraconazole (ITZ), ketoconazole (KTZ), and voriconazole (VRZ) by a checkerboard microdilution method and determined the enzymatic profile of these species with the API-ZYM kit. Most interactions were additive (27.5%, 32.5% and 5%) or indifferent (70%, 50% and 52.5%) for TRB+KTZ, TRB+ITZ and TRB+VRZ, respectively. Antagonisms were observed in 42.5% of isolates for the TRB+VRZ combination. Based on enzymatic profiling, the Sporothrix schenckii strains were categorized into 14 biotypes. Leucine arylamidase (LA) activity was observed only for S. albicans and S. mexicana. The species S. globosaand S. mexicanawere the only species without β-glucosidase (GS) activity. Our results may contribute to a better understanding of virulence and resistance among species of the genus Sporothrixin further studies. PMID:26422151

  11. Sporothrix schenckii COMPLEX:SUSCEPTIBILITIES TO COMBINED ANTIFUNGAL AGENTS AND CHARACTERIZATION OF ENZYMATIC PROFILES.

    Science.gov (United States)

    Oliveira, Daniele Carvalho; de Loreto, Érico Silva; Mario, Débora Alves Nunes; Lopes, Paulo G Markus; Neves, Louise Vignolles; da Rocha, Marta Pires; Santurio, Janio Morais; Alves, Sydney Hartz

    2015-01-01

    Sporothrix schenckii was reclassified as a complex encompassing six cryptic species, which calls for the reassessment of clinical and epidemiological data of these new species. We evaluated the susceptibility of Sporothrix albicans(n = 1) , S. brasiliensis(n = 6) , S. globosa(n = 1), S. mexicana(n = 1) and S. schenckii(n = 36) to terbinafine (TRB) alone and in combination with itraconazole (ITZ), ketoconazole (KTZ), and voriconazole (VRZ) by a checkerboard microdilution method and determined the enzymatic profile of these species with the API-ZYM kit. Most interactions were additive (27.5%, 32.5% and 5%) or indifferent (70%, 50% and 52.5%) for TRB+KTZ, TRB+ITZ and TRB+VRZ, respectively. Antagonisms were observed in 42.5% of isolates for the TRB+VRZ combination. Based on enzymatic profiling, the Sporothrix schenckii strains were categorized into 14 biotypes. Leucine arylamidase (LA) activity was observed only for S. albicans and S. mexicana. The species S. globosa and S. Mexicana were the only species without β-glucosidase (GS) activity. Our results may contribute to a better understanding of virulence and resistance among species of the genus Sporothrix in further studies.

  12. PAXIP1 Potentiates the Combination of WEE1 Inhibitor AZD1775 and Platinum Agents in Lung Cancer.

    Science.gov (United States)

    Jhuraney, Ankita; Woods, Nicholas T; Wright, Gabriela; Rix, Lily; Kinose, Fumi; Kroeger, Jodi L; Remily-Wood, Elizabeth; Cress, W Douglas; Koomen, John M; Brantley, Stephen G; Gray, Jhanelle E; Haura, Eric B; Rix, Uwe; Monteiro, Alvaro N

    2016-07-01

    The DNA damage response (DDR) involves a complex network of signaling events mediated by modular protein domains such as the BRCA1 C-terminal (BRCT) domain. Thus, proteins that interact with BRCT domains and are a part of the DDR constitute potential targets for sensitization to DNA-damaging chemotherapy agents. We performed a pharmacologic screen to evaluate 17 kinases, identified in a BRCT-mediated interaction network as targets to enhance platinum-based chemotherapy in lung cancer. Inhibition of mitotic kinase WEE1 was found to have the most effective response in combination with platinum compounds in lung cancer cell lines. In the BRCT-mediated interaction network, WEE1 was found in complex with PAXIP1, a protein containing six BRCT domains involved in transcription and in the cellular response to DNA damage. We show that PAXIP1 BRCT domains regulate WEE1-mediated phosphorylation of CDK1. Furthermore, ectopic expression of PAXIP1 promotes enhanced caspase-3-mediated apoptosis in cells treated with WEE1 inhibitor AZD1775 (formerly, MK-1775) and cisplatin compared with cells treated with AZD1775 alone. Cell lines and patient-derived xenograft models expressing both PAXIP1 and WEE1 exhibited synergistic effects of AZD1775 and cisplatin. In summary, PAXIP1 is involved in sensitizing lung cancer cells to the WEE1 inhibitor AZD1775 in combination with platinum-based treatment. We propose that WEE1 and PAXIP1 levels may be used as mechanism-based biomarkers of response when WEE1 inhibitor AZD1775 is combined with DNA-damaging agents. Mol Cancer Ther; 15(7); 1669-81. ©2016 AACR. PMID:27196765

  13. Phase I trial evaluating the antiviral agent Cidofovir in combination with chemoradiation in cervical cancer patients

    Science.gov (United States)

    Deutsch, Eric; Haie-Meder, Christine; Bayar, Mohamed Amine; Mondini, Michele; Laporte, Mélanie; Mazeron, Renaud; Adam, Julien; Varga, Andrea; Vassal, Gilles; Magné, Nicolas; Chargari, Cyrus; Lanoy, Emilie; Pautier, Patricia; Levy, Antonin; Soria, Jean-Charles

    2016-01-01

    Purpose This phase I trial aimed to assess the safety and determine the recommended Phase II dose (RP2D) of Cidofovir combined with chemoradiotherapy in patients with stage IB2-IVA cervical cancer. Experimental design Incremental doses (1, 2.5, 5 and 6.5 mg/kg) of IV Cidofovir were administered weekly for two weeks, and then every 2 weeks from the start of chemoradiotherapy to the initiation of utero-vaginal brachytherapy. Biological expression of HPV was analyzed during treatment and tumor response was assessed according to RECIST v1.0 criteria. Results A total of 15 patients were treated with Cidofovir. Dose-limiting toxicities occurred in 2/6 patients at the 6.5 mg/kg dose level (G3 proteinuria, and G3 acute pyelonephritis with G3 febrile neutropenia). No toxicity occurred at the 5 mg/kg dose level, but only 3 patients received this dose due to trial interruption because of low accrual. The most frequent G3-4 adverse effects observed during the trial were: abdominal pain (n=3), infection (n=2), leuckoneutropenia (n=2), and others (n=6). No toxic death or major renal side effect occurred. The best response was that 8/9 evaluable patients achieved a complete response (89%). In the intention to treat population, the 2-year overall and progression-free survival rates were 93% and 76%, respectively. Biological monitoring of HPV-related markers (decreased p16 expression, and increased p53 and pRb levels) was possible on sequential tumor biopsy samples. The genomic alterations identified were PIK3CA (n=5; one also had a KRAS mutation), and HRAS (n=1) mutations. Conclusion Cidofovir at a dose of 5mg/kg combined with chemoradiotherapy appeared tolerable and yielded tumor regressions. Due to early trial interruption, the RP2D was not confirmed. PMID:27016411

  14. 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

  15. Combined perfusion and doppler imaging using plane-wave nonlinear detection and microbubble contrast agents.

    Science.gov (United States)

    Tremblay-Darveau, Charles; Williams, Ross; Milot, Laurent; Bruce, Matthew; Burns, Peter N

    2014-12-01

    Plane-wave imaging offers image acquisition rates at the pulse repetition frequency, effectively increasing the imaging frame rates by up to two orders of magnitude over conventional line-by-line imaging. This form of acquisition can be used to achieve very long ensemble lengths in nonlinear modes such as pulse inversion Doppler, which enables new imaging trade-offs that were previously unattainable. We first demonstrate in this paper that the coherence of microbubble signals under repeated exposure to acoustic pulses of low mechanical index can be as high as 204 ± 5 pulses, which is long enough to allow an accurate power Doppler measurement. We then show that external factors, such as tissue acceleration, restrict the detection of perfusion at the capillary level with linear Doppler, even if long Doppler ensembles are considered. Hence, perfusion at the capillary level can only be detected with ultrasound through combined microbubbles and Doppler imaging. Finally, plane-wave contrast-enhanced power and color Doppler are performed on a rabbit kidney in vivo as a proof of principle. We establish that long pulse-inversion Doppler sequences and conventional wall-filters can create an image that simultaneously resolves both the vascular morphology of veins and arteries, and perfusion at the capillary level with frame rates above 100 Hz.

  16. The Impact of Nonpolymerizable Swelling Agents On The Synthesis of Particles With Combined Geometric, Interfacial, and Compositional Anisotropy.

    Science.gov (United States)

    Wang, Sijia; Wu, Ning

    2015-07-28

    Seeded emulsion polymerization is by far the most successful synthetic method for making anisotropic particles with precise control and high throughput. However, this synthesis involves multiple steps and the types of anisotropic properties that have been made on particles are limited. Here, we demonstrate, by using two different types of nonpolymerizable swelling agents, that we can simplify this method while still producing colloidal dimers with combined anisotropic properties in geometry, interface, and composition. When we swell cross-linked polystyrene seed particles with a simple solvent toluene, without additional polymerization steps we can make dimers with asymmetric distribution of surface charges and roughness on two lobes by fast extraction of toluene. We further show that this toluene-swelling-extraction method can promote the surface modification of the second lobe selectively especially for hydrophilic and stimuli-responsive polymers, which was a significant challenge in dimer synthesis. When we change the swelling agent to a sol-gel precursor, that is, tetraethyl orthosilicate, we can make polystyrene-silica hybrid particles with different morphologies. Our method provides a facile synthetic platform for making colloidal particles with different types of anisotropic properties, which are expected to find important applications for colloidal surfactant, self-assembly, and artificial motors.

  17. Ferulic acid-carbazole hybrid compounds: Combination of cholinesterase inhibition, antioxidant and neuroprotection as multifunctional anti-Alzheimer agents.

    Science.gov (United States)

    Fang, Lei; Chen, Mohao; Liu, Zhikun; Fang, Xubin; Gou, Shaohua; Chen, Li

    2016-02-15

    In order to search for novel multifunctional anti-Alzheimer agents, a series of ferulic acid-carbazole hybrid compounds were designed and synthesized. Ellman's assay revealed that the hybrid compounds showed moderate to potent inhibitory activity against the cholinesterases. Particularly, the AChE inhibition potency of compound 5k (IC50 1.9μM) was even 5-fold higher than that of galantamine. In addition, the target compounds showed pronounced antioxidant ability and neuroprotective property, especially against the ROS-induced toxicity. Notably, the neuroprotective effect of 5k was obviously superior to that of the mixture of ferulic acid and carbazole, indicating the therapeutic effect of the hybrid compound is better than the combination administration of the corresponding mixture.

  18. 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...

  19. Capecitabine in combination with novel targeted agents in the management of metastatic breast cancer: underlying rationale and results of clinical trials.

    Science.gov (United States)

    Tripathy, Debu

    2007-04-01

    At present there is no established standard of care for metastatic breast cancer and prognosis remains poor, although the use of newer chemotherapeutic regimens has led to modest improvements in survival. Capecitabine, an oral prodrug of 5-fluorouracil, is a promising addition to these approaches, having already shown single-agent activity against metastatic breast cancer. Following a pivotal trial demonstrating that capecitabine confers increased survival when used in combination with docetaxel, it is being investigated intensively in combined regimens using other standard chemotherapeutic agents, as well as with novel molecularly targeted therapies. Among the novel agents, the most intensively studied in combination with capecitabine is trastuzumab. Despite preclinical data suggesting that these two agents might not show additive effects, clinical trials have been very encouraging for both heavily pretreated patients and for patients receiving first-line therapy in the metastatic setting. This work is being further extended in an ongoing trial in the neoadjuvant setting. An initial trial in combination with bevacizumab, enrolling heavily pretreated patients, was less successful, but following the example of the E2100 trial, this combination is being re-examined in less heavily treated patients. In addition, this review discusses ongoing trials with an array of newer molecularly targeted agents. Significant improvement in time to progression has already been demonstrated in the combination of lapatinib and capecitabine compared with capecitabine monotherapy; for the most part, however, these trials are still in early stages.

  20. Development and Validation of Stability-Indicating RP-HPLC Method for Simultaneous Determination of Metformin HCl and Glimepiride in Fixed-Dose Combination.

    Science.gov (United States)

    Vaingankar, Pradnya N; Amin, Purnima D

    2016-01-01

    A simple reversed-phase high-performance liquid chromatography method was developed and validated for simultaneous determination of Metformin hydrochloride (MET) and Glimepiride (GLM) in combination and estimation of their principal degradation products. The separation was achieved using JASCO Finepak SIL (250 mm × 4.6 mm i.d. 5 μm) at ambient temperature. The optimized mobile phase composed of an aqueous phase (20 mM phosphate buffer, adjusted to pH 3.0) and an organic phase (methanol:acetonitrile; 62.5:37.5) in the ratio of 80:20. The flow rate was 1 mL/minute, and the analytes were detected at 230 nm. The developed method was validated for accuracy, precision, specificity, linearity, and sensitivity. The chromatographic analysis time was approximately six minutes with the complete resolution of MET (Rt = 2.75 minutes) and GLM (Rt = 5.87 minutes). The method exhibited good linearity over the range of 5-30 μg/mL for MET and 1-10 μg/mL for GLM. The drugs in combination were subjected to various stress degradation studies as per the International Conference Harmonization (ICH) guidelines. Results obtained from the stress degradation studies revealed that the developed method is applicable for stability studies. PMID:26997866

  1. Postcolumn HPLC Detection of Mono- and Oligosaccharides with a Chemosensor

    Science.gov (United States)

    Kim, Kyu Kwang; Escobedo, Jorge O.; St. Luce, Nadia N.; Rusin, Oleksandr; Wong, Douglas; Strongin, Robert M.

    2012-01-01

    Novel chromophoric compound 1 promotes the HPLC postcolumn detection of mono- and oligosaccharides. The detection of chromatographic peaks in the visible region for glucose, fructose, maltodextrins, sialic acid, and a ganglioside can be accomplished with a standard UV–vis detector. The use of selective, reversible binding agents in automated HPLC assays should allow for improved monitoring of specific analytes as well as material recovery. PMID:14682751

  2. Combined use of high-resolution α-glucosidase inhibition profiling and HPLC-HRMS-SPE-NMR for investigation of antidiabetic principles in crude plant extracts

    DEFF Research Database (Denmark)

    Kongstad, Kenneth Thermann; Özdemir, Ceylan; Barzak, Asmah;

    2015-01-01

    Type 2 diabetes is a metabolic disorder affecting millions of people worldwide, and new drug leads or functional foods containing selective α-glucosidase inhibitors are needed. Crude extract of 24 plants were assessed for α-glucosidase inhibitory activity. Methanol extracts of Cinnamomum zeylanicum...... bark, Rheum rhabarbarum peel, and Rheum palmatum root and ethyl acetate extracts of C. zeylanicum bark, Allium ascalonicum peel, and R. palmatum root showed IC50 values below 20 μg/mL. Subsequently, high-resolution α-glucosidase profiling was used in combination with high-performance liquid...... chromatography–high-resolution mass spectrometry–solid-phase extraction–nuclear magnetic resonance spectroscopy for identification of metabolites responsible for the α-glucosidase inhibitory activity. Quercetin (1) and its dimer (2), trimer (3), and tetramer (4) were identified as main α-glucosidase inhibitors...

  3. 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.

  4. 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

  5. Combination of Estrogen and Immunosuppressive Agents to Establish a Mouse Model of Candidiasis with Concurrent Oral and Vaginal Mucosal Infection.

    Science.gov (United States)

    Wang, Le; Wang, Chong; Mei, Huan; Shen, Yongnian; Lv, Guixia; Zeng, Rong; Zhan, Ping; Li, Dongmei; Liu, Weida

    2016-02-01

    Mouse model is an appropriate tool for pathogenic determination and study of host defenses during the fungal infection. Here, we established a mouse model of candidiasis with concurrent oral and vaginal mucosal infection. Two C. albicans strains sourced from clinical candidemia (SC5314) and mucosal infection (ATCC62342) were tested in ICR mice. The different combinational panels covering estrogen and immunosuppressive agents, cortisone, prednisolone and cyclophosphamide were used for concurrent oral and vaginal candidiasis establishment. Prednisolone in combination with estrogen proved an optimal mode for concurrent mucosal infection establishment. The model maintained for 1 week with fungal burden reached at least 10(5) cfu/g of tissue. This mouse model was evaluated by in vivo pharmacodynamics of fluconazole and host mucosal immunity of IL-17 and IL-23. Mice infected by SC5314 were cured by fluconazole. An increase in IL-23 in both oral and vaginal homogenates was observed after infection, while IL-17 only had a prominent elevation in oral tissue. This model could properly mimic complicated clinical conditions and provides a valuable means for antifungal assay in vivo and may also provide a useful method for the evaluation of host-fungal interactions.

  6. 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.

  7. 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

  8. 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.

  9. 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

  10. Comparison of reversal and adverse effects of sugammadex and combination of -Anticholinergic-Anticholinesterase agents in pediatric patients

    Directory of Open Access Journals (Sweden)

    Çiğdem Özgün

    2014-01-01

    Full Text Available Background: We aimed to compare clinical effects of sugammadex versus combination of anticholinergic-anticholinesterase agents for reversing of nondepolarizing neuromuscular block in pediatric patients. Materials and Methods: A total of 60 pediatric patients whom should be performed general anesthesia in the supine position were enrolled to this randomized double-blinded clinical trial. Fentanyl 1 μg/kg, propofol 2 mg/kg, rocuronium 0.6 mg/kg were used in induction and sevofluran, 50% O 2 -50% N 2 O in maintenance of anesthesia. Neuromuscular conductions were assessed by train of four (TOF-Watch SX (Organon, Schering-Plough, Ireland acceleromyograph. Patients were intubated at the moment of TOF 0. At the end of the operation emergence of T2 point was replied by 2 mg/kg sugammadex administration in group 1 and 0.06 mg/kg neostigmine +0.02 mg/kg atropine in group 2. At the moment of T0.9 inhalation, gases were ceased, and patients were extubated. Hemodynamic alterations, access to T0.9, extubation time, recovery parameters, drug consumptions and adverse effects were recorded. Results: Train of four scores showed a lesser increase in group 2 than group 1 from 15 th s to 30 th min during post reverse period (from 6.9 ± 6.4 to 91.7 ± 7.2 in group 2 vs. from 35.4 ± 21.4 to 99.5 ± 1.0 in group 1 (p < 0.0004. Group 1 patients exhibited much more complete muscle strength rates than group 2 (P < 0.001. T0.9 and extubation times were significantly longer in group 2 than group 1 (P < 0.001. Comparison of adverse effects yielded no difference. Conclusion: Sugammadex can be considered as a safe agent in order to reverse neuromuscular block in pediatric patients.

  11. Methods and applications of HPLC-AMS

    Science.gov (United States)

    Buchholz, Bruce A.; Dueker, Stephen R.; Lin, Yumei; Clifford, Andrew J.; Vogel, John S.

    2000-10-01

    Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a 14C-labeled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the 14C 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 tentatively identified by co-elution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the 14C 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 14C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected 14C activity <0.17 Bq (4.5 pCi) on the HPLC column.

  12. 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

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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

  18. The comparison of removing plug by ultrasonic wave, chemical deplugging agent and ultrasound-chemical combination deplugging for near-well ultrasonic processing technology.

    Science.gov (United States)

    Wang, Zhenjun; Xu, Yuanming; Bajracharya, Suman

    2015-11-01

    Near-well ultrasonic processing technology is characterized by high adaptability, simple operation, low cost and zero pollution. The main plugs of oil production include paraffin deposition plug, polymer plug, and drilling fluid plug etc. Although some good results have been obtained through laboratory experiments and field tests, systematic and intensive studies are absent for certain major aspects, such as: effects of ultrasonic treatment for different kinds of plugs and whether effect of ultrasound-chemicals combination deplugging is better than that of ultrasonic deplugging. In this paper, the experiments of removing drilling fluid plug, paraffin deposition plug and polymer plug by ultrasonic wave, chemical deplugging agent and ultrasound-chemical combination deplugging respectively are carried out. Results show that the effect of ultrasound-chemical combination deplugging is clearly better than that of using ultrasonic wave and chemical deplugging agent separately, which indicates that ultrasonic deplugging and chemical deplugging can produce synergetic effects. On the one hand, ultrasonic treatment can boost the activity of chemical deplugging agent and turn chemical deplugging into dynamic chemical process, promoting chemical agent reaction speed and enhancing deplugging effect; on the other hand, chemical agent can reduce the adhesion strength of plugs so that ultrasonic deplugging effect can be improved significantly. Experimental results provide important reference for near-well ultrasonic processing technology. PMID:26186853

  19. The comparison of removing plug by ultrasonic wave, chemical deplugging agent and ultrasound-chemical combination deplugging for near-well ultrasonic processing technology.

    Science.gov (United States)

    Wang, Zhenjun; Xu, Yuanming; Bajracharya, Suman

    2015-11-01

    Near-well ultrasonic processing technology is characterized by high adaptability, simple operation, low cost and zero pollution. The main plugs of oil production include paraffin deposition plug, polymer plug, and drilling fluid plug etc. Although some good results have been obtained through laboratory experiments and field tests, systematic and intensive studies are absent for certain major aspects, such as: effects of ultrasonic treatment for different kinds of plugs and whether effect of ultrasound-chemicals combination deplugging is better than that of ultrasonic deplugging. In this paper, the experiments of removing drilling fluid plug, paraffin deposition plug and polymer plug by ultrasonic wave, chemical deplugging agent and ultrasound-chemical combination deplugging respectively are carried out. Results show that the effect of ultrasound-chemical combination deplugging is clearly better than that of using ultrasonic wave and chemical deplugging agent separately, which indicates that ultrasonic deplugging and chemical deplugging can produce synergetic effects. On the one hand, ultrasonic treatment can boost the activity of chemical deplugging agent and turn chemical deplugging into dynamic chemical process, promoting chemical agent reaction speed and enhancing deplugging effect; on the other hand, chemical agent can reduce the adhesion strength of plugs so that ultrasonic deplugging effect can be improved significantly. Experimental results provide important reference for near-well ultrasonic processing technology.

  20. Ceftolozane/tazobactam and ceftazidime/avibactam: two novel β-lactam/β-lactamase inhibitor combination agents for the treatment of resistant Gram-negative bacterial infections.

    Science.gov (United States)

    Liscio, Jordan L; Mahoney, Monica V; Hirsch, Elizabeth B

    2015-09-01

    The rise in resistant Gram-negative bacteria is a major concern and has led to difficulty in treating multidrug-resistant (MDR) infections. Two recently approved combination antibiotics, ceftolozane/tazobactam and ceftazidime/avibactam, may be effective in treating these resistant infections. Ceftolozane is a novel cephalosporin that has been developed in combination with tazobactam, a recognised β-lactamase inhibitor (BLI). Avibactam is a novel BLI combined with ceftazidime, a cephalosporin with an established history. Both of these β-lactam/BLI combination agents have been shown to retain in vitro activity against selected resistant Gram-negative pathogens, including Enterobacteriaceae and Pseudomonas aeruginosa; notably, ceftazidime/avibactam has demonstrated consistent activity against Klebsiella pneumoniae carbapenemase (KPC)-producing organisms. Both agents have been approved for the indications of complicated intra-abdominal infection (with metronidazole) and complicated urinary tract infection, and have ongoing phase 3 trials for the treatment of ventilator-associated and nosocomial pneumonia. This manuscript will review current data available regarding the spectrum of activity and clinical trials that led to the US Food and Drug Administration (FDA) approval of these agents. Both agents appear to be well tolerated and show promise in the treatment of MDR Gram-negative infections.

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. How should immunomodulators be optimized when used as combination therapy with anti-tumor necrosis factor agents in the management of inflammatory bowel disease?

    Science.gov (United States)

    Ward, Mark G; Irving, Peter M; Sparrow, Miles P

    2015-10-28

    In the last 15 years the management of inflammatory bowel disease has evolved greatly, largely through the increased use of immunomodulators and, especially, anti-tumor necrosis factor (anti-TNF) biologic agents. Within this time period, confidence in the use of anti-TNFs has increased, whilst, especially in recent years, the efficacy and safety of thiopurines has been questioned. Yet despite recent concerns regarding the risk: benefit profile of thiopurines, combination therapy with an immunomodulator and an anti-TNF has emerged as the recommended treatment strategy for the majority of patients with moderate-severe disease, especially those who are recently diagnosed. Concurrently, therapeutic drug monitoring has emerged as a means of optimizing the dosage of both immunomodulators and anti-TNFs. However the recommended therapeutic target levels for both drug classes were largely derived from studies of monotherapy with either agent, or studies underpowered to analyze outcomes in combination therapy patients. It has been assumed that these target levels are applicable to patients on combination therapy also, however there are few data to support this. Similarly, the timing and duration of treatment with immunomodulators when used in combination therapy remains unknown. Recent attention, including post hoc analyses of the pivotal registration trials, has focused on the optimization of anti-TNF agents, when used as either monotherapy or combination therapy. This review will instead focus on how best to optimize immunomodulators when used in combination therapy, including an evaluation of recent data addressing unanswered questions regarding the optimal timing, dosage and duration of immunomodulator therapy in combination therapy patients.

  8. 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

  9. Progress on the Studies of HPLC-MS-NMR Combined Techniques and Its Application in Active Principles of Natural Drugs%HPLC-MS-NMR联用技术及其在天然药物活性成分研究中的应用进展

    Institute of Scientific and Technical Information of China (English)

    陈执中

    2006-01-01

    综述HPLC-MS-NMR联用技术几种主要连接模式,HPLC-MS-NMR联用对天然提取物活性成分的高通量筛选(HTS)及在天然药物的分离和鉴定如天然药物贯叶连翘(Hypericum perforatum L.)提取物中的萘二恩酮、类黄酮类及其他成分的在线分离和结构鉴定、苹果皮中槲皮素糖苷类和根皮素糖苷类成分的鉴定和确认以及南非钩麻(Harpagophytum procambens DC)中萜苷异构体鉴定等方面的研究应用进展.

  10. 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.

  11. 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

  12. 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)

  13. Determination of Plasma Concentration of Fluconazol and Midazolam Combinations for Children by HPLC Method%氟康唑联用咪达唑仑血药浓度测定方法及相互作用

    Institute of Scientific and Technical Information of China (English)

    陆晓彤; 刘艳; 徐阿晶; 舒扬; 张春; 王芳; 林志燕

    2012-01-01

    Objective: To establish a biological sample pre-treatment method to extract fluconazole and midazolam simultaneously. HPLC methods were separately established to determine fluconazol, midazolam and 1 -hydroxymidazolam in serum. Whether the plasma concentration of midazolam affected by fluconzole and midazolam combinations was also investigated in this study. Methods: The blood samples ( 1 mL) were extracted with ethyl acetate (5 mL). The organic extract was concentrated to dryness under a mild nitrogen fumes stream. The residue was dissolved in methanol ( 100 μL) , and 20 μL of it was used for HPLC analyze under different conditions. Results: Fluconazol, midazolam and 1 -hydroxymidazolam could be extracted in the same condition. The calibration curves for fluconazol had a good linearity over the range of 0. 5 ~ 20 μg · mL-1 (r = 0. 9970, n = 6). The calibration curves for midazolam had a good linearity over the range of 0.03 ~7. 29 μg · mL-1 (r = 0. 9985, n= 16). The calibration curves for 1-hydroxymidazolam had a good linearity over the range of 0.09 ~7.29 μg · mL (r = 0.9993, n = 5). Compared to the children treated with single in midazolam, the plasma concentration of midazolam in children who were treated with combined fluconazole and midazolam increased significantly. Conclusions: The method is sensitive, accurate, simple, rapid and applicable for clinical plasma drug level monitoring of fluconazol, midazolam and its metabolites. The plasma concentration of midazolam in children who were treated with combined fluconazole and midazolam was higher than that in the children treated only with midazolam.%目的:建立可同时进行氟康唑和咪达唑仑生物样品前处理的方法,应用RP-HPLC法分别测定氟康唑、咪达唑仑、1-羟基咪达唑仑的血药浓度;同时考察氟康唑与咪达唑仑联用对咪达唑仑血药浓度的影响.方法:1 mL血清样品加入内标后以5 mL乙酸乙酯提取,有机相用氮气吹干,以100 μL甲

  14. 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...

  15. 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, ...

  16. 辐射防护药物的优化组合研究%Screen of Combination of Radioprotective Agents

    Institute of Scientific and Technical Information of China (English)

    邵帅; 谭洪玲; 肖成荣; 洪倩; 霍超; 王宇光; 梁乾德; 马增春; 高月

    2012-01-01

    目的 选择目前已有的辐射防护药物(包括化学药物、中药复方及细胞因子),研究联合用药的辐射防护活性,筛选最佳药物组合,为新的急性放射损伤治疗方案提供实验依据.方法 试验分为模型对照组,E0703+ rhG-CSF+新型四物合用组(组合Ⅰ),E0703+ rhIL-11+刺白胶囊合用组(组合Ⅱ),E0703+ rhG-CSF+新型四物合用组(组合Ⅲ),E0703+rhIL-11+刺白胶囊合用组(组合Ⅳ),523 +rhG-CSF+新型四物合用组(组合Ⅴ),523 +rhIL-11+刺白胶囊合用组(组合Ⅵ),523 +rhG-CSF+刺白胶囊合用组(组合Ⅶ),523+ rhIL-11+刺白胶囊合用组(组合Ⅷ),共9组药物组合.60Coγ射线7.5 Gy照射造模,照射前24 h按组分别给予化学药物预防,照后皮下注射细胞因子,并灌胃给予中药.照射前,照射后1、4、7、10、13、16、22 d检测小鼠外周血象.照射后第7天进行祖细胞集落培养实验.结果 与模型对照组比较,除组合Ⅶ外,其余各组合对外周血液成分在不同时间点呈现不同程度的促进恢复作用;而对各造血祖细胞集落的生长,组合Ⅰ、Ⅲ的作用最为显著;其中,组合Ⅲ尚有促外周血白细胞、红细胞、血红蛋白值恢复的作用;组合Ⅴ也有加速外周血液成分恢复和促进粒系生长的作用.结论 综合比较,组合Ⅲ对促进外周血液各成分恢复和造血祖细胞生长均有较好效果.%Objective To screen the best combination of radioprotectors by pretreating and curing cobalt-60 gamma irradiated mice with combined. Methods Synthetic compounds (E0703, 523) were used as preventive a-gents, cytokine ( rhG-CSF, rhIL-11) was used to cure early acute radiation damage, and tradiational Chinese medicine formulas (new si-wu capsules, ci-bai capsules) were used to reverse late radiation damage. Ninety mice were irradiated at a dose of 7. 5 Gy using cobalt-60 gamma resources. Blood samples were collected from the tail end and the number of peripheral blood cells was counted

  17. 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...

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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...

  3. 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.

  4. Comparative biorelease study of fluticasone in combination with antibacterial (Neomycin and or antifungal (coltrimazol, miconazole agents by histamine percutaneous reaction method in healthy volunteers

    Directory of Open Access Journals (Sweden)

    Shahani S

    1997-01-01

    Full Text Available Fluticasone propionate is a novel, potent and topically active synthetic corticosteroid preparation with a much reduced potential, in relation to its anti-inflammatory potency, for unwanted systemic side effects. It is indicated for the treatment of eczema, dermatitis etc. The objective of the present study was to evaluate and compare the biorelease of fluticassone with placebo (base formulation; its combination with antifungal (miconazole, clotrimazole and / or antibacterial agents based on the attenuation of histamine induced wheal and flare reaction and flare intensity (on visual analouge scale by McNemar test. In the present study, fluticasone alone and in combination with clotrimazole, miconazole and neomycin significantly reduced the wheal and flare response of histamine prick test. The flare intensity response was also significantly inhibited by these treatments. Furthermore, there was no difference in the anti-inflammatory activity of various treatment groups. It may, therefore, be concluded that antibacterial (neomycin and / or antifungal (miconazole, clotrimazole agents in combination with steroid (fluticasone do not alter the pharmacodynamic response of the latter.

  5. 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.

  6. 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)

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. Degradation of sunscreen agent p-aminobenzoic acid using a combination system of UV irradiation, persulphate and iron(II).

    Science.gov (United States)

    Xue, Yicen; Dong, Wenbo; Wang, Xiaoning; Bi, Wenlong; Zhai, Pingping; Li, Hongjing; Nie, Minghua

    2016-03-01

    Increased usage and discharge of sunscreens have led to ecological safety crisis, and people are developing the advanced oxidation processes (AOPs) to treat them. The present study aimed to determine the degradation efficiency and mechanism of the sunscreen agent p-aminobenzoic acid (PABA) using the UV/Fe(2+)/persulphate (PS) method. A series of irradiation experiments were conducted to optimise the system conditions and to study the impacts of the natural anion. Free radicals and degradation products were identified in order to clarify the degradation mechanism. Initial PS and Fe(2+) concentrations showed significant impacts on PABA degradation. Natural anions, such as Cl(-), NO3 (-), H2PO4 (-) and HCO3 (-), impeded PABA degradation because of ion (Fe(2+)) capture, radical scavenging or pH effects. Hydroxyl (HO·) and sulphate (SO4 (·-)) radicals were two main radicals observed in the UV/Fe(2+)/PS system; of these, SO4 (·-) showed greater effects on PABA degradation. Over 99 % of the available PABA was completely degraded into carbon dioxide (CO2) and water (H2O) by the UV/Fe(2+)/PS system, and the remaining PABA participated in complex radical reactions. By-products were identified by total ion chromatography and mass spectrometry. Our research provides a treatment process for PABA with high degradation efficiency and environmental safety and introduces a new strategy for sunscreen degradation.

  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. A quinoxaline derivative as a potent chemotherapeutic agent, alone or in combination with benznidazole, against Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    Jean Henrique da Silva Rodrigues

    Full Text Available BACKGROUND: Chagas' disease is a condition caused by the protozoan Trypanosoma cruzi that affects millions of people, mainly in Latin America where it is considered endemic. The chemotherapy for Chagas disease remains a problem; the standard treatment currently relies on a single drug, benznidazole, which unfortunately induces several side effects and it is not successful in the cure of most of the chronic patients. In order to improve the drug armamentarium against Chagas' disease, in the present study we describe the synthesis of the compound 3-chloro-7-methoxy-2-(methylsulfonyl quinoxaline (quinoxaline 4 and its activity, alone or in combination with benznidazole, against Trypanosoma cruzi in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Quinoxaline 4 was found to be strongly active against Trypanosoma cruzi Y strain and more effective against the proliferative forms. The cytotoxicity against LLCMK2 cells provided selective indices above one for all of the parasite forms. The drug induced very low hemolysis, but its anti-protozoan activity was partially inhibited when mouse blood was added in the experiment against trypomastigotes, an effect that was specifically related to blood cells. A synergistic effect between quinoxaline 4 and benznidazole was observed against epimastigotes and trypomastigotes, accompanied by an antagonistic interaction against LLCMK2 cells. Quinoxaline 4 induced several ultrastructural alterations, including formations of vesicular bodies, profiles of reticulum endoplasmic surrounding organelles and disorganization of Golgi complex. These alterations were also companied by cell volume reduction and maintenance of cell membrane integrity of treated-parasites. CONCLUSION/SIGNIFICANCE: Our results demonstrated that quinoxaline 4, alone or in combination with benznidazole, has promising effects against all the main forms of T. cruzi. The compound at low concentrations induced several ultrastructural alterations and led the

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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)

  20. 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.

  1. 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

  2. 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

  3. What role do combinations of interferon and targeted agents play in the first-line therapy of metastatic renal cell carcinoma?

    Science.gov (United States)

    Bukowski, Ronald M

    2008-12-01

    Interferons (IFNs) are a class of cytokines with pleotropic actions that regulate a variety of cellular activities. Clinical trials with recombinant IFNs (IFN-alpha2a and IFN-alpha2b) have demonstrated clinical activity in patients with advanced renal cell carcinoma (RCC). Their efficacy is characterized by a low overall tumor regression rate of < 15%, progression-free survival of 4-5 months, and overall median survival of 10-18 months. This cytokine became the standard of care for patients with metastatic RCC and was then used as the comparator arm in a series of phase II and III clinical trials that have defined a new treatment paradigm for patients with advanced RCC. This paradigm uses the tyrosine kinase inhibitors (TKIs) sorafenib and sunitinib, the mammalian target of rapamycin (mTOR) inhibitor temsirolimus, and the vascular endothelial growth factor monoclonal antibody bevacizumab. These 3 categories of agents were then investigated in combination with IFN-alpha in a series of preclinical and clinical studies. The collective data from these reports suggest the combination of IFN-alpha and bevacizumab is active and has a role in RCC therapy, whereas combinations with the TKIs or mTOR inhibitors have limited efficacy and/or excessive toxicity. The clinical and preclinical studies leading to these conclusions are reviewed herein.

  4. 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

    Directory of Open Access Journals (Sweden)

    Chao Lien Liu

    2016-06-01

    Full Text Available 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.

  5. 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.

  6. Determination of peroxide value in soft capsule containing coenzyme Q10 by titration combined with HPLC%HPLC辅助滴定法测定含辅酶Q10保健食品中过氧化值

    Institute of Scientific and Technical Information of China (English)

    何小稳; 黎承; 鲁燕妮; 曾德斌; 邢奇芬

    2013-01-01

    目的 通过研究含辅酶Q10软胶囊保健食品中过氧化值含量偏高的现象,建立了一种可排除辅酶Q10干扰的HPLC辅助滴定法测定该类样品中过氧化值的方法. 方法 采用GB/T5009.56中方法提取辅酶Q10软胶囊中的油脂,HPLC法测定油脂中辅酶Q10的含量,并采用GB/T5009.37中硫代硫酸钠滴定法分别滴定油脂和辅酶Q10的过氧化值,通过计算排除辅酶Q10的干扰达到测定含辅酶Q10软胶囊保健食品中过氧化值的目的. 结果 HPLC方法中辅酶Q10在2.00~32.0μg·mL-1(r=0.9998)的范围内线性关系良好.所建的HPLC辅助滴定法通过植物油中添加定量的辅酶Q10标准品验证了所建方法的可行性,含辅酶Q10软胶囊保健食品中过氧化值含量的加标回收率为98.4%,RSD为0.88%. 结论 该方法排除了辅酶Q10的干扰,解决了该类样品中过氧化值含量偏高的问题,结果准确,适用于含辅酶Q10软胶囊保健食品中过氧化值的测定.%Objective To determine peroxide value in soft capsule containing coenzyme Q10 by studying the high peroxide value in these samples. Methods The HPLC was used to determining the content of coenzyme Q10 in the grease in soft capsule containing coenzyme Q10 based on GB/T5009.56 and sodium thiosulfate titration method was used to determine the peroxide value in soft capsule coenzyme containing Q10 was obtained by getting rid of the interference based on GB/T5009.37. Results A good linear relation was obtained in the range of 2.00~32.0 μg·mL-l for coenzyme Q10 (r=0.9998)by HPLC. The feasibility of HPLC auxiliary titration method was verified by adding quantitative coenzyme Q10 in oil. The recovery was 98.4% with the relative standard deviations of 0.88%. Conclusions The proposed method is proved to be accurate with no interference of coenzyme Q10. It is suitable for the determination of peroxide value in soft capsule containing coenzyme Q10.

  7. Anti-cancer effects of novel flavonoid vicenin-2 as a single agent and in synergistic combination with docetaxel in prostate cancer.

    Science.gov (United States)

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

    2011-11-01

    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 with decreasing c-Myc, cyclin D1, cyclin B1, CDK4, PCNA and hTERT in vitro. VCN-2 reached a level of 2.6±0.3μmol/l in serum after oral administration in mice which reflected that VCN-2 is orally absorbed. The i.v. administration of docetaxel (DTL), current drug of choice in androgen-independent CaP, is associated with dose-limiting toxicities like febrile neutropenia which has lead to characterization of alternate routes of administration and potential combinatorial regimens. In this regard, VCN-2 in combination with DTL synergistically inhibited the growth of prostate tumors in vivo with a greater decrease in the levels of AR, pIGF1R, pAkt, PCNA, cyclin D1, Ki67, CD31, and increase in E-cadherin. VCN-2 has been investigated for radioprotection and anti-inflammatory properties. This is the first study on the anti-cancer effects of VCN-2. In conclusion, our investigations collectively provide strong evidence that VCN-2 is effective against CaP progression along with indicating that VCN-2 and DTL co-administration is more effective than either of the single agents in androgen-independent prostate cancer.

  8. 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

  9. Effect of high pressure, in combination with antilisterial agents, on the growth of Listeria monocytogenes during extended storage of cooked chicken.

    Science.gov (United States)

    Patterson, M F; Mackle, A; Linton, M

    2011-12-01

    A cocktail of Listeria monocytogenes strains was inoculated into cooked chicken (∼2.2 × 10³ CFU g⁻¹) which was then pressure-treated (600 MPa/2 min/20 °C) and stored for up to 105 days at 8 °C. In addition, sodium lactate (2% w/w) or a pressure-resistant Weissella viridescens strain, known to have antilisterial activity, were added to the meat prior to inoculation with the pathogen and pressure treatment, to investigate the effect on Listeria survival. Pressure treatment alone was not sufficient to eliminate all of the Listeria. Numbers of survivors were initially below the level of detection (50 CFU g⁻¹) but increased during storage to reach >10⁸ CFU g⁻¹ by day 21. The presence of W. viridescens significantly extended the lag phase of any Listeria that survived the initial pressure treatment by ∼35 days, but numbers then increased to reach ∼10⁷ CFU g⁻¹ by day 105. The addition of 2% sodium lactate in combination with pressure treatment was most effective at inhibiting the growth of L. monocytogenes and numbers remained below the limit of detection throughout the 105 day storage. The addition of antimicrobial agents, in combination with pressure, could be used to give additional food safety assurance without increasing pressure hold time.

  10. 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

  11. 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.

  12. [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

  13. 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。

  14. 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.

  15. 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.

  16. 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

  17. 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。

  18. 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

  19. 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

  20. A Theranostic Agent Combining a Two-Photon-Absorbing Photosensitizer for Photodynamic Therapy and a Gadolinium(III) Complex for MRI Detection.

    Science.gov (United States)

    Schmitt, Julie; Heitz, Valérie; Sour, Angélique; Bolze, Frédéric; Kessler, Pascal; Flamigni, Lucia; Ventura, Barbara; Bonnet, Célia S; Tóth, Éva

    2016-02-18

    The convergent synthesis and characterization of a potential theranostic agent, [DPP-ZnP-GdDOTA](-), which combines a diketopyrrolopyrrole-porphyrin component DPP-ZnP as a two-photon photosensitizer for photodynamic therapy (PDT) with a gadolinium(III) DOTA complex as a magnetic resonance imaging probe, is presented. [DPP-ZnP-GdDOTA](-) has a remarkably high longitudinal water proton relaxivity (19.94 mm(-1)  s(-1) at 20 MHz and 25 °C) for a monohydrated molecular system of this size. The Nuclear Magnetic Relaxation Dispersion (NMRD) profile is characteristic of slow rotation, related to the extended and rigid aromatic units integrated in the molecule and to self-aggregation occurring in aqueous solution. The two-photon properties were examined and large two-photon absorption cross-sections around 1000 GM were determined between 910 and 940 nm in DCM with 1 % pyridine and in DMSO. Furthermore, the new conjugate was able to generate singlet oxygen, with quantum yield of 0.42 and 0.68 in DCM with 1 % pyridine and DMSO, respectively. Cellular studies were also performed. The [DPP-ZnP-GdDOTA](-) conjugate demonstrated low dark toxicity and was able to induce high one-photon and moderate two-photon phototoxicity on cancer cells.

  1. Novel Role of Rural Official Organization in the Biomass-Based Power Supply Chain in China: A Combined Game Theory and Agent-Based Simulation Approach

    Directory of Open Access Journals (Sweden)

    Kaiyan Luo

    2016-08-01

    Full Text Available Developing biomass-based power generation is helpful for China to reduce the dependence on fossil fuels and to release the targets of carbon emission peak. The decentralized farming method leads to Chinese farmers’ weak willingness to collect and sell crop residues to biomass-based power plants. The purpose of this paper is to solve the issue by proposing a novel biomass feedstock supply model with China’s rural official organization—villagers’ committee, which has great influence on villagers’ decision making. Introducing it into the biomass-based power supply chain is beneficial to motivating farmers’ supplying enthusiasm. A combined game theory and agent-based simulation approach is applied to study the effectiveness of this new supply model. Multiple simulation scenarios are built to study impacts of different simulation parameters, and results show that farmers tend to supply more biomass material for electricity production in the proposed villagers’ committee model, compared with the two conventional supply models, direct-deal and broker models. The supply model incorporating the rural official organization can ensure the feedstock sufficiency for plants. A proper model design depends on the feed-in tariff subsidy for biomass-based electricity, feedstock shipping distance, performance appraisal system of the villagers’ committee, as well as farmers’ utility weights on net income and public service improvement.

  2. 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

  3. 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

  4. 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.)

  5. Comprehensive quality evaluation of Chishao by HPLC.

    Science.gov (United States)

    Zaiyou, Jian; Wenquan, Wang; Guifang, Xu; Li, Meng; Junling, Hou

    2013-01-01

    Objetivo: El propósito de este artículo es la evaluación cualitativa extensa de Chishao. Métodos: En el experimento de este trabajo, se establecen los espectros de identificación de Chishao en todas las localizaciones mediante RP-HPLC y el método del análisis de componentes principales con las áreas pico de RPHPLC. Resultados: La calidad de Chishao en el norte de China o del procedente de Paeonia lactiflora es mejor que la de otras localizaciones o procedente de P. obovata, P. mairei y P. anomala. Los resultados son congruentes con la impresión tradicional de la calidad de esta planta. Estos resultados indican que el análisis de los componentes principales (ACP) puede utilizarse como método eficaz y económico para evaluar la calidad de Chishao y podría aplicarse a otras plantas medicinales chinas. Conclusiones: Dada la complicada base de la eficacia de la Medicina tradicional china (MTC), un método como el ACP para diversos componentes químicos parece ser más adecuado para la evaluación de la calidad de la MTC en comparación con la determinación de un único o unos pocos agentes químicos.

  6. 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

  7. 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

  8. 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...

  9. 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.)

  10. 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

  11. A field survey of metal binding to metallothionein and other cytosolic ligands in liver of eels using an on-line isotope dilution method in combination with size exclusion (SE) high pressure liquid chromatography (HPLC) coupled to Inductively Coupled Plasma time-of-flight Mass Spectrometry (ICP-TOFMS).

    Science.gov (United States)

    Van Campenhout, Karen; Goenaga Infante, Heidi; Goemans, Geert; Belpaire, Claude; Adams, Freddy; Blust, Ronny; Bervoets, Lieven

    2008-05-15

    The effect of metal exposure on the accumulation and cytosolic speciation of metals in livers of wild populations of European eel with special emphasis on metallothioneins (MT) was studied. Four sampling sites in Flanders showing different degrees of heavy metal contamination were selected for this purpose. An on-line isotope dilution method in combination with size exclusion (SE) high pressure liquid chromatography (HPLC) coupled to Inductively Coupled Plasma time-of-flight Mass Spectrometry (ICP-TOFMS) was used to study the cytosolic speciation of the metals. The distribution of the metals Cd, Cu, Ni, Pb and Zn among cytosolic fractions displayed strong differences. The cytosolic concentration of Cd, Ni and Pb increased proportionally with the total liver levels. However, the cytosolic concentrations of Cu and Zn only increased above a certain liver tissue threshold level. Cd, Cu and Zn, but not Pb and Ni, were largely associated with the MT pool in correspondence with the environmental exposure and liver tissue concentrations. Most of the Pb and Ni and a considerable fraction of Cu and Zn, but not Cd, were associated to High Molecular Weight (HMW) fractions. The relative importance of the Cu and Zn in the HMW fraction decreased with increasing contamination levels while the MT pool became progressively more important. The close relationship between the cytosolic metal load and the total MT levels or the metals bound on the MT pool indicates that the metals, rather than other stress factors, are the major factor determining MT induction.

  12. 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

  13. 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.

  14. 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.

  15. 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...

  16. 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.

  17. METHODS ELABORATION ON DETECTION OF SOME ATYPICAL NEUROLYTIC AGENTS FOR CHEMICAL AND TOXICOLOGICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    I. P. Remezova

    2014-01-01

    Full Text Available It is necessary to elaborate methods of atypical neuroleptic agents detection as individual substances and in different combinations as well for diagnosis of poisoning by some of them: clozapine, risperidone, sertindole, olanzapine, aripiprazole. The purpose of this work is methods elaboration of detection of clozapine, risperidone, sertindole, olanzapine, aripiprazole, haloperidol, oxazepam, carbamazapine using TLC, HPLC and UV spectrophotometry methods. During this work we used tablet forms of clozapine, risperidone, sertindole, olanzapine, aripiprazole. It is possible to use solution systems like ethanol-water-25% ammonia solution (8:1:1, toluolacetone-ethanol-25% ammonia solution (45:45:7.5:2.5, dioxan-chloroform-acetone-25% ammonia solution (47.5:45:5:2.5 for preliminary examination of atypical neuroleptic agents under study in combination with typical neuroleptics and tranquilizers with undirected analysis (general screening. System of solvents ethyl-acetate-chloroform-25% ammonia solution (85:10:5 is recommended to use for individual screening of risperidone, sertindole, olanzapine, haloperidol, benzol-ethanol-25% ammonia solution (50:10:0.5 system to use for clozapine, sertindole, olanzapine. Ethanol-25% ammonia solution (100:1.5 system is reasonable to use for chromatographic clearance of extracts from biological substances under study. We recommend using HPLC method and UV spectrophotometry for carrying out of a principal examination of clozapine, risperidone, sertindole, olanzapine and aripiprazole in case one of the substances under study is determined in the object.

  18. Applying theoretical premises of binary toxicity mathematical modeling to combined impacts of chemical plus physical agents (A case study of moderate subchronic exposures to fluoride and static magnetic field).

    Science.gov (United States)

    Katsnelson, B A; Tsepilov, N A; Panov, V G; Sutunkova, M P; Varaksin, A N; Gurvich, V B; Minigalieva, I A; Valamina, I E; Makeyev, O H; Meshtcheryakova, E Y

    2016-09-01

    Sodium fluoride solution was injected i.p. to rats at a dose equivalent to 0.1 LD50 three times a week up to 18 injections. Two thirds of these rats and of the sham-injected ones were exposed to the whole body impact of a 25 mT static magnetic field for 2 or 4 h a day, 5 times a week. For mathematical analysis of the effects they produced in combination, we used a response surface model. This analysis demonstrated that (like in combined toxicity) the combined adverse action of a chemical plus a physical agent was characterized by a diversity of types depending not only on particular effects these types were assessed for but on their level as well. From this point of view, the indices for which at least one statistically significant effect was observed could be classified as identifying (1) single-factor action; (2) additivity; (3) synergism; (4) antagonism (both subadditive unidirectional action and all variants of contradirectional action). Although the classes (2) and (3) taken together encompass a smaller part of the indices, the biological importance of some of them renders the combination of agents studied as posing a higher health risk than that associated with each them acting alone.

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. Determination of Steviosin in Combine Bacillus Subtilis and Enterococcus Faecium Granules with Multivitamines,live By RP-HPLC%反相高效液相色谱法测定枯草杆菌二联活菌颗粒中甜菊糖苷的含量

    Institute of Scientific and Technical Information of China (English)

    孙菲; 孙欣

    2016-01-01

    Objective To establish RP-HPLC method for determination of Steviosin in Combine Bacilus Subtilis and Enterococcus Faecium Granules with Multivitamines,live.Methods Using a column packed with AgiLent Zobax SB-C18 (250 mm×4.6 mm,5μm);The mobile phase was acetonitrile-0.002 mol/L H3pO4 by gradient elution and the detection wavelength was 210 nm;the flow rate was 1.0ml/min,the injection volume was 10μl,the column temperature was 30℃.Results The Linear response of Steviosin range from 5.160~103.2μg/ml r=0.9999(n=7);The average recovery of Steviosin was 99.04%,RSD= 0.6%(n=6).Conclusion The method is convenient and accurate and can be used for the quality control of Combine Bacilus Subtilis and Enterococcus Faecium Granules with Multivitamines,live.%目的:建立反相高效液相色谱(RP-HPLC)法测定枯草杆菌二联活菌颗粒中甜菊糖苷的含量。方法选用AgiLent Zobax SB-C18(250 mm×4.6 mm,5μm)为色谱柱,线性梯度洗脱,流动相为乙腈-0.002 mol/L磷酸溶液;检测波长为210 nm;流速1.0 ml/min;进样量10μl;柱温30℃。结果甜菊糖苷的线性范围为5.160~103.2 g/ml(r=0.9999,n=7);提取回收率为99.04%(RSD为0.6%,n=6)。结论本法操作简便、准确,可用于枯草杆菌二联活菌颗粒的质量控制。

  5. 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

  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. Detection and characterization of hepatocellular carcinoma in rats with liver cirrhosis:diagnostic value of combined use of MR positive and negative contrast agents

    Institute of Scientific and Technical Information of China (English)

    Dong-Mei Guo; Tian-Shuang Qiu; Jie Bian; Shu-Feng Liu; Chang-Zheng Wang

    2009-01-01

    BACKGROUND:Gadolinium-enhanced multi-phase dynamic imaging has improved the accuracy of the diagnosis of hypervascular hepatocellular carcinoma (HCC), but using gadolinium-enhanced dynamic imaging alone is problematic in evaluating hypovascular HCC. This work aimed at evaluating the combined use of superparamagnetic iron oxide (SPIO)-enhanced and gadolinium set in distinguishing HCCs from regenerative nodules (RNs) in a rat model induced by diethylnitrosamine (DEN). METHODS:DEN-induced HCC model rats (n=40) and control rats (n=10) were studied. From weeks 16 to 19 after DEN administration, 4 animals were scanned every week. The hepatic changes were tested with a 1.5 Tesla magnet, and MR images of SPIO-enhanced and gadolinium set were obtained. According to the pathologic changes, the tumorigenesis was divided into HCC and RN (diameter of nodules≥3 mm). Diagnostic accuracy of the combined SPIO-enhanced and gadolinium set and the gadolinium set alone was evaluated using receiver-operating characteristic curves. Sensitivity and speciifcity of the combined SPIO-enhanced and gadolinium set and the gadolinium set alone were calculated.RESULTS:The listed tests were completed in 29 rats (21 treated and 8 controls). One hundred and six nodules (82 HCCs, 24 RNs) were analyzed. The Az value and sensitivity with the combined SPIO-enhanced and gadolinium set (Az 0.94, sensitivity 0.96) were higher than those with the gadolinium set alone (Az 0.92, sensitivity 0.89). Using the combined SPIO-enhanced and gadolinium set led to detection of 6 nodules which were negative in the gadolinium set alone and 3 nodules were correctly characterized. CONCLUSION:Using the combined SPIO-enhanced and gadolinium set improved the detectability of HCCs and the SPIO-enhanced imaging compensated for the gadolinium set in differentiating HCCs from RNs in a rat model.

  8. 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

  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. Clinical results obtained with a combination of an anti-inflammatory steroid, an antibacterial agent and an antifungal in dermatological outpatient practice.

    Science.gov (United States)

    Pazzaglia, A

    1985-07-01

    Forty outpatients with skin diseases were treated with an extempore combination of three creams, the respective bases of which were beclomethasone dipropionate, sodium fusidate and ketoconazole. Positive results were obtained in 97.5% of the cases with good relief of symptoms and excellent local tolerance in all cases treated.

  11. 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.

  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. 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

  14. 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

  15. 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

  16. In vitro cytotoxicity of novel pro-apoptotic agent DM-PIT-1 in PEG-PE-based micelles alone and in combination with TRAIL

    Science.gov (United States)

    Skidan, Igor; Miao, Benchun; Thekkedath, Ritesh V; Dholakia, Parita; Degterev, Alexei; Torchilin, Vladimir

    2011-01-01

    PURPOSE Develop and characterize a micellar formulations of N-{[(2-hydroxy-5-nitrophenyl)amino]carbonothioyl}-3,5-dimethylbenzamide (DM-PIT-1) – a new small molecule non-lipid antagonist of phopshotidylinositol-3.4.5-triphopshate and inhibitor of the PI3-kinase pathway. METHODS Micelle-forming PEG2000-PE was used to solubilize DM-PIT-1. To improve the specificity of the micellar DM-PIT-1, cancer-targeting anti-nucleosomal mAb2C5 antibodies as well as Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL) were attached to the surface of polymeric micelles. RESULTS DM-PIT-1 was effectively incorporated (>70%) into 14–16 nm micelles, which had a negative surface zeta potential of 4–5 mV. Micellar DM-PIT-1 demonstrated high in vitro cytotoxicity against various cancer cells. An improved potency of the dual-activity DM-PIT-1/TRAIL combination nanoparticles in inducing death of TRAIL-resistant cancer cells was shown. Efficacy of the TRAIL therapy was enhanced by combining it with the 2C5 antibody cancer-targeted micellar form of DM-PIT-1. CONCLUSIONS DM-PIT-1 micellar preparations can be used for targeted combination therapy against TRAIL-resistant cancers. PMID:19555308

  17. The combination of a low-dose chemotherapeutic agent, 5-fluorouracil, and an adenoviral tumor vaccine has a synergistic benefit on survival in a tumor model system.

    Directory of Open Access Journals (Sweden)

    Sean M Geary

    Full Text Available Standard cancer therapies, particularly those involving chemotherapy, are in need of modifications that both reduce short-term and long-term side effects as well as improve the overall survival of cancer patients. Here we show that combining low-dose chemotherapy with a therapeutic vaccination using an adenovirus encoding a model tumor-associated antigen, ovalbumin (Ad5-OVA, had a synergistic impact on survival in tumor-challenged mice. Mice that received the combinatorial treatment of Ad5-OVA plus low-dose 5-fluorouracil (5-FU had a 95% survival rate compared to 7% and 30% survival rates for Ad5-OVA alone and 5-FU alone respectively. The presence of 5-FU enhanced the levels of OVA-specific CD8(+ T lymphocytes in the spleens and draining lymph nodes of Ad5-OVA-treated mice, a phenomenon that was dependent on the mice having been tumor-challenged. Thus 5-FU may have enhanced survival of Ad5-OVA-treated mice by enhancing the tumor-specific immune response combined with eliminating tumor bulk. We also investigated the possibility that the observed therapeutic benefit may have been derived from the capacity of 5-FU to deplete MDSC populations. The findings presented here promote the concept of combining adenoviral cancer vaccines with low-dose chemotherapy.

  18. Differential effects of natural product microtubule stabilizers on microtubule assembly: single agent and combination studies with taxol, epothilone B, and discodermolide.

    Science.gov (United States)

    Gertsch, Jürg; Meier, Sarah; Müller, Martin; Altmann, Karl-Heinz

    2009-01-01

    A systematic comparison has been performed of the morphology and stability of microtubules (MTs) induced by the potent microtubule-stabilizing agents (MSAs) taxol, epothilone B (Epo B), and discodermolide (DDM) under GTP-free conditions. DDM-induced tubulin polymerization occurred significantly faster than that induced by taxol and Epo B. At the same time, tubulin polymers assembled from soluble tubulin by DDM were morphologically distinct (shorter and less ordered) from those induced by either taxol or Epo B, as demonstrated by electron microscopy. Exposure of MSA-induced tubulin polymers to ultrasound revealed the DDM-based polymers to be less stable to this type of physical stress than those formed with either Epo B or taxol. Interestingly, MT assembly in the presence of both DDM and taxol appeared to produce a distinct new type of MT polymer with a mixed morphology between those of DDM- and taxol-induced structures. The observed differences in MT morphology and stability might be related, at least partly, to differences in intramicrotubular tubulin isotype distribution, as DDM showed a different pattern of beta-tubulin isotype usage in the assembly process.

  19. 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.

  20. 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.…

  1. 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...

  2. 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

  3. Anti-CD20 as the B cells targeting agent in the combined therapy to modulate anti-factor VIII immune responses in hemophilia A inhibitor mice

    Directory of Open Access Journals (Sweden)

    Chao Lien eLiu

    2014-01-01

    Full Text Available Neutralizing antibody formation against transgene products can represent a major complication following gene therapy with treatment of genetic diseases, such as hemophilia A. Although successful approaches have been developed to prevent the formation of anti-factor VIII (FVIII antibodies, innovative strategies to overcome pre-existing anti-FVIII immune responses in FVIII-primed subjects are still lacking. Anti-FVIII neutralizing antibodies circulate for long periods in part due to persistence of memory B cells. Anti-CD20 targets a variety of B cells (pre-B cells to mature/memory cells; therefore, we investigated the impact of B cell depletion on anti-FVIII immune responses in hemophilia A mice using anti-CD20 combined with regulatory T (Treg cell expansion using IL-2/IL-2mAb complexes plus rapamycin. We found that anti-CD20 alone can partially modulate anti-FVIII immune responses in both unprimed and FVIII-primed hemophilia A mice. Moreover, in mice treated with anti-CD20 + IL-2/IL-2mAb complexes + rapamycin + FVIII, anti-FVIII antibody titers were significantly reduced in comparison to mice treated with regimens targeting only B or T cells. In addition, titers remained low after a second challenge with FVIII plasmid . Treg cells and activation markers were transiently and significantly increased in the groups treated with IL-2/IL-2mAb complexes ; however,significant B cell depletion was obtained in anti-CD20-treated groups. Importantly, both FVIII-specific antibody-secreting cells and memory B cells were significantly reduced in mice treated with combination therapy. This study demonstrates that a combination regimen is highly promising as a treatment option for modulating anti-FVIII antibodies and facilitating induction of long-term tolerance to FVIII in hemophilia A mice.

  4. 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

  5. Combined action of PSC 833 (Valspodar), a novel MDR reversing agent, with mitoxantrone, etoposide and cytarabine in poor-prognosis acute myeloid leukemia.

    Science.gov (United States)

    Visani, G; Milligan, D; Leoni, F; Chang, J; Kelsey, S; Marcus, R; Powles, R; Schey, S; Covelli, A; Isidori, A; Litchman, M; Piccaluga, P P; Mayer, H; Malagola, M; Pfister, C

    2001-05-01

    PSC 833 (Valspodar) can reverse multidrug resistance (MDR) in patients with hematologic malignancies, but alters the pharmacokinetics of concomitant anticancer agents. A phase I, dose-finding study was initiated to define a safe and effective regimen of mitoxantrone, etoposide, and cytarabine (MEC) when administered with PSC 833 to patients with early relapsed or refractory acute myeloid leukemia (AML). Poor-prognosis AML patients refractory to first-line induction therapy or relapsing within 9 months of attaining complete remission (CR) were treated with cytarabine (1.0 g/m2/day), etoposide (30 mg/m2/day), and mitoxantrone at a dose of either 3.0 mg/m2/day (cohort 1) or 4.5 mg/m2/day (cohorts 2 and 3) for 6 days plus continuous-infusion PSC 833 (10 mg/kg/24 h with a 2.0 mg/kg loading dose) for 6 or 7 days each 21-day cycle. Patients achieving CR were given a 4-day MEC plus PSC 833 consolidation cycle. Twenty-three patients were enrolled (eight with primary refractory AML and 15 in relapse). Dose-limiting toxicity occurred in one of six patients in cohort 2 (grade 4 mucositis) and one of seven patients in cohort 3 (grade 4 hyperbilirubinemia). The maximum tolerated dose of mitoxantrone was defined as 4.5 mg/m2/day. Clinically significant grade 4 hyperbilirubinemia, possibly related to PSC 833, occurred in four patients. Hematologic toxicities were as expected in this patient population, but were not dose limiting. Mild to moderate cerebellar ataxia and paresthesia occurred in six (26%) and five (22%) patients, respectively, but were not dose limiting. Overall, six of 23 (26%) patients achieved CR, including five patients with demonstrated P-glycoprotein expression and/or function. The median overall survival was 4 months. All six patients with a CR were alive and four (17%) patients were disease free at 12 months. Blood levels of PSC 833 were well above the target level of 1000 ng/ml, a concentration that is known to reverse MDR in vitro. PSC 833 reduced the

  6. 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.

  7. 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

    Science.gov (United States)

    Hodge, Rebecca J.; Paulik, Mark A.; Walker, Ann; Boucheron, Joyce A.; McMullen, Susan L.; Gillmor, Dawn S.; Nunez, Derek J.

    2016-01-01

    Background 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. Nonclinical Results 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. Clinical Results 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)]. Conclusions 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. Trial

  8. 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.

  9. 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

  10. 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

    with the combination of the two over 5-7 years of follow-up. We also assessed comparative safety. METHODS: In a multicentre, open-label trial, 4447 patients with type 2 diabetes on metformin or sulfonylurea monotherapy with mean haemoglobin A(1c) (HbA(1c)) of 7.9% were randomly assigned to addition of rosiglitazone (n.......80-1.63) for myocardial infarction, and 0.72 (0.49-1.06) for stroke. Heart failure causing admission to hospital or death occurred in 61 people in the rosiglitazone group and 29 in the active control group (HR 2.10, 1.35-3.27, risk difference per 1000 person-years 2.6, 1.1-4.1). Upper and distal lower limb fracture rates...... failure and of some fractures, mainly in women. Although the data are inconclusive about any possible effect on myocardial infarction, rosiglitazone does not increase the risk of overall cardiovascular morbidity or mortality compared with standard glucose-lowering drugs. FUNDING: GlaxoSmithKline plc, UK....

  11. 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.

  12. [Determination of azoxystrobin in tea by HPLC].

    Science.gov (United States)

    Chonan, T

    2001-08-01

    A determination method has been developed for azoxystrobin in tea by HPLC. Azoxystrobin was extracted from a sample with acetone, and the extract was passed through an alumina column to remove tannin. The eluate was concentrated to ca. 25 mL and passed through a Sep-Pak Vac tC18 to remove pigments. The eluate was cleaned-up by using liquid-liquid partition, and Florisil and silica-gel columns. The HPLC analysis for azoxystrobin was carried out on a C18 column with acetonitrile-water (9:11) as the mobile phase, with ultraviolet detection at 260 nm. The recovery of azoxystrobin fortified at the level of 0.4 microgram/g was 90.2% and the limit of determination was 0.2 microgram/g.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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."

  20. 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。

  1. 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...

  2. 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 ...

  3. 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 ...

  4. 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

  5. Spectrophotometric and HPLC methods for simultaneous estimation of pseudoephedrine hydrochloride and loratadine from tablets

    Directory of Open Access Journals (Sweden)

    Singhvi I

    2006-01-01

    Full Text Available Two simple, accurate, economical and reproducible UV spectrophotometric and one HPLC method for simultaneous estimation of two-component drug mixture of pseudoephedrine hydrochloride and loratadine in combined tablet dosage form have been developed. The first developed method employs multiwavelength spectroscopy using seven mixed standards and 257.0 nm and 283.0 nm as two wavelengths for estimation. The second method involves first derivative spectroscopy using 308.6 nm and 263.0 nm as zero crossing points for pseudoephedrine hydrochloride and loratadine respectively. For both spectrophotometric methods, 0.2 M hydrochloric acid was used as solvent. Linearity was observed in concentration range of 0-40 mg/ml of loratadine and 0-800 mg/ml of pseudoephedrine hydrochloride. Developed HPLC method is reverse-phase chromatographic method using Inertsil C 18 column and methanol:ammonium acetate buffer in ratio of 80:20 pH 7.5 as mobile phase. Nimesulide was used as internal standard for HPLC method. For HPLC method, linearity was observed in concentration range of 0-200 mg/ml of loratadine and 100-2000 mg/ml of pseudoephedrine hydrochloride. Results of analysis were validated statistically and by recovery studies.

  6. 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

  7. 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...

  8. Implementing Lego Agents Using Jason

    CERN Document Server

    Jensen, Andreas Schmidt

    2010-01-01

    Since many of the currently available multi-agent frameworks are generally mostly intended for research, it can be difficult to built multi-agent systems using physical robots. In this report I describe a way to combine the multi-agent framework Jason, an extended version of the agent-oriented programming language AgentSpeak, with Lego robots to address this problem. By extending parts of the Jason reasoning cycle I show how Lego robots are able to complete tasks such as following lines on a floor and communicating to be able to avoid obstacles with minimal amount of coding. The final implementation is a functional extension that is able to built multi-agent systems using Lego agents, however there are some issues that have not been addressed. If the agents are highly dependent on percepts from their sensors, they are required to move quite slowly, because there currently is a high delay in the reasoning cycle, when it is combined with a robot. Overall the system is quite robust and can be used to make simple...

  9. 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.

  10. 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.

  11. 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 ...

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  18. 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...

  19. Novel efficient combined method for the treatment of wastewater from fluorescent agent production%荧光剂生产废水新型高效组合处理方法

    Institute of Scientific and Technical Information of China (English)

    陶汶銘; 张蒙茜; 郭士明; 刘静; 杨燕菲; 曹琦; 高建峰

    2015-01-01

    荧光增白剂废水对人体和环境有很大危害。采用回收废酸、H 2O 2、石灰等廉价试剂,通过酸性净化—微波+Fenton氧化法—碱化—生物法联合方法,处理某化工厂的荧光废水,使其COD从5480 mg/L降至75 mg/L。该方法以废治废,生产成本低,净化效果显著。%The wastewater from fluorescent-whitening agent production is very harmful to the ecological environment and human health. The wastewater of a chemical plant has been treated with recovered waste acid,H2O2,lime and other inexpensive reagents by the combined process,acidulation purification-microwave+Fenton oxidation-alkaliza-tion-biological method. Its COD can be decreased from 5 480 mg/L to 75 mg/L. This process is characterized by treating waste with waste,low cost,and remarkable purification effect.

  20. 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...

  1. 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…

  2. 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...

  3. Application of low tube current combined with lower contrast agent in the head and neck dual-source CT angiography%双源CT双低扫描在头颈部血管成像中的应用

    Institute of Scientific and Technical Information of China (English)

    李姝琪; 郭君武

    2015-01-01

    developing strength in cerebral arteries angiography between group C and group A (P=0.236),but the image noise was sligbtly larger in group C than group A (P =0.212).Conclusions Application of low tube current combined with low concentration of contrast agent in the head and neck dual-source CT angiography is feasible in clinical diagnosis,with good clinical value.It can not only get better image quality,but also meet the needs of clinical diagnosis.

  4. 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

  5. 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.

  6. 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.)

  7. 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.

  8. 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

  9. 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.

  10. 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

    2016-03-11

    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.

  11. 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)

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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)

  18. 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.

  19. 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.

  20. Direct 13C NMR Detection in HPLC Hyphenation Mode

    DEFF Research Database (Denmark)

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

    2012-01-01

    Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments...... application of HPLC-SPE-NMR analysis using direct-detected (13)C NMR spectra. HPLC column loading, accumulative SPE trappings, and the effect of different elution solvents were evaluated and optimized. A column loading of approximately 600 mug of a prefractionated triterpenoid mixture, six trappings...

  1. 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.

  2. Determination of carbonyl compounds in air by HPLC; Determinacion de compuestos carbonilicos en aire por HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.; Perez, R.M.; Campos, A.; Gonzalez, D.

    1995-07-01

    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 acetoacetonitrile. Three different types of samples (rural, urban, petrol emission) were successfully analyzed. (Author) 12 refs.

  3. Multi-agent Justification Logic : communication and evidence elimination

    NARCIS (Netherlands)

    Renne, Bryan

    2012-01-01

    This paper presents a logic combining , a framework for reasoning about multi-agent communication, with a new multi-agent version of , a framework for reasoning about evidence and justification. This novel combination incorporates a new kind of that cleanly meshes with the multi-agent communications

  4. 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

  5. Interacting agents in finance

    NARCIS (Netherlands)

    C. Hommes

    2008-01-01

    Interacting agents in finance represent a behavioural, agent-based approach in which financial markets are viewed as complex adaptive systems consisting of many boundedly rational agents interacting through simple heterogeneous investment strategies, constantly adapting their behaviour in response t

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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 ...

  11. 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

  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. 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

  14. Determination of Trace Metal Impurities in Cerium Oxide by Fluorination-Assisted ETV-ICP-AES after HPLC Separation

    Institute of Scientific and Technical Information of China (English)

    Ruth Wanjau; Hu Bin(胡斌); Jiang Zucheng(江祖成); Qin Yongchao(秦永超); He Man(何蔓); Liang Pei(梁沛)

    2004-01-01

    A new method for the separation and detection of trace metal impurities in cerium oxide(CeO2)using HPLC combined with electrothermal vaporization(ETV)-ICP-AES was developed.This combination links the high separation power of HPLC and high sensitivity of ETV-ICP-AES.The 2-ethylhexyl hydrogen 2-ethylhexylphosphate(P507)resin was used as stationary phase for the separation of metallic impurities in order to eliminate severe spectral interferences of the matrix.The dilute nitric acid was adopted as mobile phase for eluting Cu,Mn,Ni and La.The separation process can be accomplished in about 30 min.After concentrating the eluate by evaporation,the trace impurities were determined by using ETV-ICP-AES with the addition of 6% PTFE slurry as chemical modifier.The proposed method was applied to the analysis of CeO2 with satisfactory recoveries.

  15. 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.

  16. UV- VIS Spectroscopic and HPLC Studies on Dictyota bartayresiana Lamour

    Institute of Scientific and Technical Information of China (English)

    Johnson Marimuthu Antonisamy; Krishnaveni Eahamban

    2012-01-01

    Objective: The present study was aimed to explore phytochemical constituents present in Dictyota bartayresiana Lamour and produce the UV-VIS and HPLC spectrum profile for Dictyotabartayresiana. Methods: Phytochemical screening of the extracts was carried out according to the standard methods. For the HPLC analysis, the methanol: water (45:55) was used as mobile phase. Results: The phytochemical results showed the presence of alkaloids, steroids, phenolic groups, saponins, tannins, glycosides and sugars. The UV- VIS profile of methanolic, petroleum ether, chloroform, isopropanol of D. bartayresiana extract showed various peaks with different functional groups. The HPLC profile of D. bartayresiana petroleum ether, chloroform and benzene extracts showed some prominent and moderate peaks with different retention time. Conclusions:The results of the present study showed that Dictyota bartayresiana Lamour may be rich sources of phytoconstituents which can be isolated and further screened for different kinds of biological activities, depending on their reported therapeutic uses.

  17. Direct Vasodilators and Sympatholytic Agents.

    Science.gov (United States)

    McComb, Meghan N; Chao, James Y; Ng, Tien M H

    2016-01-01

    Direct vasodilators and sympatholytic agents were some of the first antihypertensive medications discovered and utilized in the past century. However, side effect profiles and the advent of newer antihypertensive drug classes have reduced the use of these agents in recent decades. Outcome data and large randomized trials supporting the efficacy of these medications are limited; however, in general the blood pressure-lowering effect of these agents has repeatedly been shown to be comparable to other more contemporary drug classes. Nevertheless, a landmark hypertension trial found a negative outcome with a doxazosin-based regimen compared to a chlorthalidone-based regimen, leading to the removal of α-1 adrenergic receptor blockers as first-line monotherapy from the hypertension guidelines. In contemporary practice, direct vasodilators and sympatholytic agents, particularly hydralazine and clonidine, are often utilized in refractory hypertension. Hydralazine and minoxidil may also be useful alternatives for patients with renal dysfunction, and both hydralazine and methyldopa are considered first line for the treatment of hypertension in pregnancy. Hydralazine has also found widespread use for the treatment of systolic heart failure in combination with isosorbide dinitrate (ISDN). The data to support use of this combination in African Americans with heart failure are particularly robust. Hydralazine with ISDN may also serve as an alternative for patients with an intolerance to angiotensin antagonists. Given these niche indications, vasodilators and sympatholytics are still useful in clinical practice; therefore, it is prudent to understand the existing data regarding efficacy and the safe use of these medications. PMID:26033778

  18. 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

  19. Subunit Characteristics of Pig Pancreas Ferritin Revealed by MALDI-TOF MS and RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    HUANG Lin; LIN Zhi-cao; LIN Qing; LUO Lian-zhong; HUANG He-qing

    2008-01-01

    Pig pancreas ferritin(PPF) was purified by ultra-centrifugation,ion-exchange chromatography,and native gradient polyacrylamide gel electrophoresis(PAGENG).Sodium dodecyl sulfate(SDS)-PAGE indicates that PPF consists of two subunit types,namely,H(21000) and L(19000) subunits,and its core shows an average element composition of 1698 Fe3+ and 179 phosphate molecules within the hollow shell,giving a 9.5:1 ratio of Fe3+ to phosphate.An off line approach combining reversed-phase high-performance liquid chromatography(RP-HPLC) with matrix-assisted laser desorption ionization time of flight mass speetrometry(MALDI-TOF MS) made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry(MS),giving molecular weights of both H(21014.4) and L(18319.9)subunits.Both subunit types were further identified by an approach combining peptide mass fingerprint(PMF) with database search.A ratio of IH to 2L subunits in PPF was determined by SDS-PAGE,RP-HPLC,and MALDI-TOF MS,respectively.It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF,which may be further used to explain the unclear physiological function between H and L subunits in PPF.

  20. 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.

  1. 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.

  2. 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)

  3. 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...

  4. 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

  5. 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.

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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 ...

  11. 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

  12. 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.

  13. Agent Reward Shaping for Alleviating Traffic Congestion

    Science.gov (United States)

    Tumer, Kagan; Agogino, Adrian

    2006-01-01

    Traffic congestion problems provide a unique environment to study how multi-agent systems promote desired system level behavior. What is particularly interesting in this class of problems is that no individual action is intrinsically "bad" for the system but that combinations of actions among agents lead to undesirable outcomes, As a consequence, agents need to learn how to coordinate their actions with those of other agents, rather than learn a particular set of "good" actions. This problem is ubiquitous in various traffic problems, including selecting departure times for commuters, routes for airlines, and paths for data routers. In this paper we present a multi-agent approach to two traffic problems, where far each driver, an agent selects the most suitable action using reinforcement learning. The agent rewards are based on concepts from collectives and aim to provide the agents with rewards that are both easy to learn and that if learned, lead to good system level behavior. In the first problem, we study how agents learn the best departure times of drivers in a daily commuting environment and how following those departure times alleviates congestion. In the second problem, we study how agents learn to select desirable routes to improve traffic flow and minimize delays for. all drivers.. In both sets of experiments,. agents using collective-based rewards produced near optimal performance (93-96% of optimal) whereas agents using system rewards (63-68%) barely outperformed random action selection (62-64%) and agents using local rewards (48-72%) performed worse than random in some instances.

  14. 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

  15. COMPARATIVE LEVELS OF RIFAMPICIN IN SERUM AND SALIVA IN TUBERCULOSIS PATIENTS BY HPLC METHOD

    Directory of Open Access Journals (Sweden)

    Mandapakala Gopala Krishna

    2016-04-01

    Full Text Available BACKGROUND Tuberculosis is a deadly disease, which can be cured only by anti-tuberculosis therapy. Anti-tuberculosis therapy will be effective only when the drugs are given in ideal combinations and doses, which can achieve adequate Minimal Inhibitory Concentrations (MIC in the tissues. Slow response to Tuberculosis (TB therapy in spite of good adherence may lead to prolonged infectiousness or acquired drug resistance, which further burdens public health systems by extending treatment duration. Hence, there is a need for measuring therapeutic drug concentrations in patients on anti-tuberculosis therapy, at least in special comorbid conditions like diabetes mellitus and HIV. High Performance Liquid Chromatography (HPLC is a sensitive and specific method of measuring rifampicin levels. OBJECTIVE To measure the levels of rifampicin in serum and saliva by HPLC technique and look for their correlation. METHODS Twenty pulmonary tuberculosis patients were divided into two groups - Group 1 (14 patients who were given 600 mg of rifampicin orally in a single dose on the day of sampling and Group 2 (6 patients given 450 mg of rifampicin. Thirteen samples of saliva and seven samples of blood (serum were collected over a period of 24 hrs. at fixed intervals from the time of drug administration in each subject. Samples are subjected to HPLC to measure rifampicin levels. RESULTS The peak heights obtained at different concentrations of the drug were plotted against the drug concentration and looked for their statistical significance. CONCLUSION In the present study, the concentrations of the drug in serum and saliva after administering single oral dose of 600/450 mg of rifampicin were correlating well throughout the time period. The required minimal inhibitory concentration of rifampicin (0.5 µg/mL is achieved in serum and saliva in both groups. Thus monitoring of rifampicin levels in saliva can be recommended in place of serum drug monitoring whenever needed.

  16. 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

  17. 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...

  18. 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...

  19. Identification of ionic chloroacetanilide-herbicide metabolites in surface water and groundwater by HPLC/MS using negative ion spray

    Science.gov (United States)

    Ferrer, I.; Thurman, E.M.; Barcelo, D.

    1997-01-01

    Solid-phase extraction (SPE) was combined with high-performance liquid chromatography/high-flow pneumatically assisted electrospray mass spectrometry (HPLC/ESP/MS) for the trace analysis of oxanilic and sulfonic acids of acetochlor, alachlor, and metolachlor. The isolation procedure separated the chloroacetanilide metabolites from the parent herbicides during the elution from C18 cartridges using ethyl acetate for parent compounds, followed by methanol for the anionic metabolites. The metabolites were separated chromatographically using reversed-phase HPLC and analyzed by negative-ion MS using electrospray ionization in selected ion mode. Quantitation limits were 0.01 ??g/L for both the oxanilic and sulfonic acids based on a 100-mL water sample. This combination of methods represents an important advance in environmental analysis of chloroacetanilide-herbicide metabolites in surface water and groundwater for two reasons. First, anionic chloroacetanilide metabolites are a major class of degradation products that are readily leached to groundwater in agricultural areas. Second, anionic metabolites, which are not able to be analyzed by conventional methods such as liquid extraction and gas chromatography/mass spectrometry, are effectively analyzed by SPE and high-flow pneumatically assisted electrospray mass spectrometry. This paper reports the first HPLC/MS identification of these metabolites in surface water and groundwater.

  20. Detection of melamine in gluten, chicken feed, and processed foods using surface enhanced Raman spectroscopy and HPLC.

    Science.gov (United States)

    Lin, M; He, L; Awika, J; Yang, L; Ledoux, D R; Li, H; Mustapha, A

    2008-10-01

    Melamine, a nitrogen-rich chemical, was implicated in pet and human food recalls in 2007, which caused enormous economic losses to the food industry. In this study, melamine concentration in wheat gluten, chicken feed, and processed foods (that is, cake and noodle) was measured by surface enhanced Raman spectroscopy (SERS) in combination with SERS-active substrates. SERS was able to rapidly detect 0.1% melamine in wheat gluten, 0.05% in chicken feed, 0.05% in cakes, and 0.07% in noodle, respectively. A partial least squares (PLS) model was established for the quantification of melamine in foods by SERS: R= 0.90, RMSEP = 0.33. In addition, SERS results were verified by HPLC analysis based on a simplified FDA method. Compared with HPLC, the SERS method is much faster and simpler, requires minimum sample preparation, but still yields satisfactory qualitative and quantitative results. These results demonstrate that it is an applicable approach to use SERS to screen foods, eliminate presumptive negative samples of melamine contamination from the sample population, and then verify presumptive positive samples using HPLC protocols. Combining these 2 methods could provide a more rapid and cost-effective way for monitoring melamine contamination in increasingly large numbers of imported foods and feed products. PMID:19019134

  1. 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.

  2. 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

  3. 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.

  4. Immunoassay screening of lysergic acid diethylamide (LSD) and its confirmation by HPLC and fluorescence detection following LSD ImmunElute extraction.

    Science.gov (United States)

    Grobosch, T; Lemm-Ahlers, U

    2002-04-01

    In all, 3872 urine specimens were screened for lysergic acid diethylamide (LSD) using the CEDIA DAU LSD assay. Forty-eight samples, mainly from psychiatric patients or drug abusers, were found to be LSD positive, but only 13 (27%) of these could be confirmed by high-performance liquid chromatography with fluorescence detection (HPLC-FLD) following immunoaffinity extraction (IAE). Additional analysis for LSD using the DPC Coat-a-Count RIA was performed to compare the two immunoassay screening methods. Complete agreement between the DPC RIA assay and HPLC-FLD results was observed at concentrations below a cutoff concentration of 500 pg/mL. Samples that were LSD positive in the CEDIA DAU assay but not confirmed by HPLC-FLD were also investigated for interfering compounds using REMEDI HS drug-profiling system. REMEDI HS analysis identified 15 compounds (parent drugs and metabolites) that are believed to cross-react in the CEDIA DAU LSD assay: ambroxol, prilocaine, pipamperone, diphenhydramine, metoclopramide, amitriptyline, doxepine, atracurium, bupivacaine, doxylamine, lidocaine, mepivacaine, promethazine, ranitidine, and tramadole. The IAE/HPLC-FLD combination is rapid, easy to perform and reliable. It can reduce costs when standard, rather than more advanced, HPLC equipment is used, especially for labs that perform analyses for LSD infrequently. The chromatographic analysis of LSD, nor-LSD, and iso-LSD is not influenced by any of the tested cross-reacting compounds even at a concentration of 100 ng/mL.

  5. Simultaneous determination of seven bioactive components in Oolong tea Camellia sinensis: quality control by chemical composition and HPLC fingerprints.

    Science.gov (United States)

    Wang, Yixiang; Li, Qing; Wang, Qian; Li, Yujiao; Ling, Junhong; Liu, Lili; Chen, Xiaohui; Bi, Kaishun

    2012-01-11

    A simple and reliable method of high-performance liquid chromatography (HPLC) was developed for the quality control of oolong tea (the dry leaves of Camellia sinensis ): the quality control included the HPLC fingerprint and the quantitative determination of seven bioactive compounds chemicals, namely, (-)-gallocatechin, (-)-epigallocatechin, (-)-epigallocatechin gallate, caffeine, (-)-epicatechin, gallocatechin gallate, and (-)-epicatechin gallate. The developed analyses of the chemicals excelled in quantifying the chemicals in oolong tea. The chemical fingerprint of oolong tea was established using the raw materials of three main production sites in China, that is, Fujian (southern and northern parts), Taiwan, and Guangdong. The fingerprints from different cultivated sources were analyzed by hierarchical cluster analysis, similarity analysis, principal component analysis (PCA), analysis of variance (ANOVA), and discriminant analysis. The results indicated that the combination of chromatographic fingerprint and quantification analysEs could be used for the quality assessment of oolong tea and its derived products. PMID:22098505

  6. 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.

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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...

  12. 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.

  13. Experience of great saphenous varicose vein high ligation main stripping operation combined with foam hardening agent in the treatment of varicose vein of lower limb%大隐静脉曲张高位结扎主干剥除术联合泡沫硬化剂治疗下肢静脉曲张的体会

    Institute of Scientific and Technical Information of China (English)

    徐庆; 肖启明; 路鹏

    2016-01-01

    Objective:To explore the curative effect of great saphenous varicose vein high ligation main stripping operation combined with foam hardening agent in the treatment of varicose vein of lower limb.Methods:36 patients with varicose vein of lower limb were selected.They were given great saphenous varicose vein high ligation main stripping operation combined with foam hardening agent.The curative effects were observed.Results:1 case was postoperative limb numbness and pain,1 case had hematoma formation after great saphenous main stripping operation.No wound infection and deep vein thrombosis were found,and no recurrence was found.Conclusion:Great saphenous varicose vein high ligation main stripping operation combined with foam hardening agent in the treatment of varicose vein of lower limb has a better treatment effect.%目的:探讨大隐静脉曲张高位结扎主干剥除术联合泡沫硬化剂治疗下肢静脉曲张疗效。方法:收治下肢静脉曲张患者36例,给予大隐静脉高位结扎主干剥除术联合泡沫硬化剂治疗,观察疗效。结果:术后患肢麻木疼痛1例,大隐静脉主干剥除后血肿形成1例,无伤口感染及深静脉血栓形成,未发现复发病例。结论:大隐静脉曲张高位结扎主干剥除术联合泡沫硬化剂治疗下肢静脉曲张具有较好的疗效。

  14. 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

  15. 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

    with 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....

  16. 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...

  17. 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

  18. Combination of bio-soaping agent and its application for cotton fabric washing%皂洗酶复配及其在染色后处理中的应用

    Institute of Scientific and Technical Information of China (English)

    董治昌

    2014-01-01

    应用漆酶DeniliteIIS进行了染液脱色与棉染物酶洗试验,考察了不同助剂对漆酶处理效果的影响。结果表明:阴离子表面活性剂十二烷基硫酸钠、螯合剂EDTA等对漆酶酶活有一定的抑制作用;非离子表面活性剂平平加O和吐温-80能增加漆酶反应活性,使脱色率(数量、比例)增加。漆酶与吐温-80复配的皂洗酶对棉染物有较好的酶洗效果,处理后织物湿摩擦牢度有所增加。%The laccase of Denilite IIS was used for dye decolorization and bio-soaping in cotton fabric. Effects of different chemical additives on the treatment result of laccase were investigated. The results indicated that anionic surfactant of sodium dodecyl sulfate and the chelating agent of EDTA inhibited the enzyme activity of laccase, while nonionic surfactants of peregal O and Tween-80 increased the activity of laccase, and raise the decolorization efficiency. The bio-soaping agent formulated by laccase and Tween-80 showed high soaping efficacy for the dyed cotton fabric and the wet rubbing fastness of the treated fabric was improved as well.

  19. Interaction between some common genotoxic agents.

    Science.gov (United States)

    Beckman, L; Nordenson, I

    1986-01-01

    The clastogenic effects of arsenic, lead and sulphur dioxide and the protective effect of selenium were studied in short-term lymphocyte cultures. The three agents selected are the major toxic substances in emissions from copper smelters. Cells from non-smoking, healthy individuals were exposed to individual agents and combinations of the four agents (sodium arsenite, lead acetate, sodium sulphite and sodium selenite) and the cells were analysed for chromosome aberrations and sister chromatide exchanges. Selenium showed an antagonistic (protective) effect against the other agents. No synergistic effects were found, and the interactions between arsenic, lead and sulphur dioxide were mainly antagonistic. These rather unexpected findings indicate that mixed exposure from copper smelters, and other mixed exposures where arsenic, lead and sulphur dioxide are involved, may cause less genetic damage than expected and that an adequate dietary supplement of selenium may reduce the genotoxic effects of these agents. PMID:3793119

  20. 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

  1. Simultaneous Quantification of Ciprofloxacin, Quinine and 3-hyrdoxyquinine in Human Plasma using a HPLC Method

    Directory of Open Access Journals (Sweden)

    Adebanjo J. Adegbola, Julius O. Soyinka , Babatunde A. Adeagbo

    2016-02-01

    Full Text Available Malaria has been shown to strongly predispose patients in areas of malaria endemicity to bacteremia with severe outcomes, thus justifying the use of antibiotics in combination with antimalarial therapy in patients with severe malaria. This study describes a High-Performance Liquid Chromatographic (HPLC method for simultaneous determinations of Ciprofloxacin (CPN, Quinine (QN, and its major metabolite, 3-Hydroxyquinine (3-HQN, in human plasma. Following a simple precipitation with acetonitrile, chromatographic separation was achieved on a reversed-phase Agilent Zorbax (CN column (5 µm, 150 X 4.6 mm i.d using a mobile phase consisting of acetonitrile: potassium dihydrogen phosphate (pH = 2.8; 0.02 M (42:58, v/v. Retention times for CPN, 3-HQN, IS and QN were 2.7, 3.3, 3.6 and 4.9 minutes respectively. The limits of detection and validated lower limits of quantitation were 30 and 70 ng/ml for both QN and 3-HQN while the corresponding values were 50 and 100 ng/ml for CPN, respectively. The new HPLC method here developed, when compared with previous methods for the analysis of either or both drugs is simple, rapid, selective, reproducible and costeffective. It is also suitable for conducting a simultaneous therapeutic monitoring of quinine and ciprofloxacin in patients when concomittantly administered as demonstrated in five healthy volunteers.

  2. Simultaneous determination of prenylflavonoid and hop bitter acid in beer lee by HPLC-DAD-MS.

    Science.gov (United States)

    Kao, T H; Wu, G Y

    2013-11-15

    An HPLC-DAD-MS method with high accuracy and precision was developed for determination of prenylflavonoids and hop bitter acids in beer lee, a by-product from beer brewing process. Four prenylflavonoids and nine hop bitter acids can be simultaneously separated in 29 min using a Thermo HyPURITY C18 column in combination with diode array dectector and mass spectrometer with HPLC solvent gradient system of phosphoric acid aqueous solution at pH 1.6 and acetonitrile at a flow rate of 1.5 mL/min and detection wavelength at 314 nm. Beer lee is found to contain isoxanthohumol (36.2 μg/g), xanthohumol (29.6 μg/g), 8-prenylnaringenin (7.84 μg/g), 6-prenylnaringenin (19.2 μg/g), cohumulone (44.7 μg/g), humulone (123 μg/g), adhumulone (21.8 μg/g), colupulone (44.2 μg/g), lupulone (33.2 μg/g), and adlupulone (5.76 μg/g).

  3. 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.

  4. Simultaneous determination of olanzapine and fluoxetine hydrochloride in capsules by spectrophotometry, TLC-spectrodensitometry and HPLC

    Directory of Open Access Journals (Sweden)

    Mahmoud A. Tantawy

    2013-03-01

    Full Text Available This paper describes sensitive, accurate and precise spectrophotometric, TLC-spectrodensitometric and high performance liquid chromatographic (HPLC methods for simultaneous determination of olanzapine and fluoxetine HCl. Two spectrophotometric methods were developed, namely; first derivative (D1 and derivative ratio (DD1 methods. The TLC method employed aluminum TLC plates precoated with silica gel GF254 as the stationary phase and methanol:toluene:ammonia (7:3:0.1, by volume as the mobile phase, where the chromatogram was scanned at 235 nm. The developed HPLC method used a reversed phase C18 column with isocratic elution. The mobile phase composed of phosphate buffer pH 4.0:acetonitrile:triethylamine (53:47:0.03, by volume at flow rate of 1.0 mL min−1. Quantitation was achieved with UV detection at 235 nm. The methods were validated according to the International Conference on Harmonization (ICH guidelines. The selectivity of the proposed methods was tested using laboratory-prepared mixtures. The developed methods were successfully applied for the determination of olanzapine and fluoxetine HCl in bulk powder and combined capsule dosage form.

  5. THE INTEGRATED AGENT IN MULTI-AGENT SYSTEMS

    OpenAIRE

    Maleković, Mirko; Čubrilo, Mirko

    2000-01-01

    [n this paper, we characterize the integrated agent in multi-agent systems. The following result is proved: if a multi-agent system is reflexive (symmetric, transitive, Euclidean) then the integrated agent of the multi-agent system is reflexive (symmetric, transitive, Euclidean), respectively. We also prove that the analogous result does not hold for multi-agent system's serial ness. A knowledge relationship between the integrated agent and agents in a multiagent system is presented.

  6. 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.

  7. 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...

  8. Brahms Mobile Agents: Architecture and Field Tests

    Science.gov (United States)

    Clancey, William J.; Sierhuis, Maarten; Kaskiris, Charis; vanHoof, Ron

    2002-01-01

    We have developed a model-based, distributed architecture that integrates diverse components in a system designed for lunar and planetary surface operations: an astronaut's space suit, cameras, rover/All-Terrain Vehicle (ATV), robotic assistant, other personnel in a local habitat, and a remote mission support team (with time delay). Software processes, called agents, implemented in the Brahms language, run on multiple, mobile platforms. These mobile agents interpret and transform available data to help people and robotic systems coordinate their actions to make operations more safe and efficient. The Brahms-based mobile agent architecture (MAA) uses a novel combination of agent types so the software agents may understand and facilitate communications between people and between system components. A state-of-the-art spoken dialogue interface is integrated with Brahms models, supporting a speech-driven field observation record and rover command system (e.g., return here later and bring this back to the habitat ). This combination of agents, rover, and model-based spoken dialogue interface constitutes a personal assistant. An important aspect of the methodology involves first simulating the entire system in Brahms, then configuring the agents into a run-time system.

  9. 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

  10. 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...

  11. Cholecalciferol sulfate identification in human milk by HPLC.

    Science.gov (United States)

    Boulch, N L; Cancela, L; Miravet, L

    1982-04-01

    Synthetic vitamin D3 sulfate was prepared by reacting cholecalciferol with sulfamic acid in pyridine. Vitamin D3 sulfate ammonium salt was purified by crystallisation and transformed in sulfate sodium salt. Homogeneity was controlled by reverse phase high pressure liquid chromatography (HPLC). Purified synthetic vitamin D3 sulfate sodium salt was used as a reference. Milk whey was obtained after protein precipitation by adding ethanol. Vitamin D3 sulfoconjugate was identified in supernatant (lyophylized) after purification by Sephadex LH 20 and HPLC. Milk whey purified fraction obtained exhibited the same ultra-violet absorption (UV) as synthetic vitamin D3 sulfate; after solvolysis, cholecalciferol was liberated from natural and synthetic sulfoconjugate. The results confirmed that vitamin D3 sulfate was present in human milk. PMID:6294930

  12. 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…

  13. 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...

  14. 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...

  15. 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

  16. 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.

  17. 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

  18. Cyclic oligomers in polyamide for food contact material: quantification by HPLC-CLND and single-substance calibration.

    Science.gov (United States)

    Heimrich, M; Bönsch, M; Nickl, H; Simat, T J

    2012-01-01

    Cyclic oligomers are the major substances migrating from polyamide (PA) food contact materials. However, no commercial standards are available for the quantification of these substances. For the first time the quantification of cyclic oligomers was carried out by HPLC coupled with a chemiluminescence nitrogen detector (CLND) and single-substance calibration. Cyclic monomer (MW = 226 Da) and dimer (MW = 452 Da) of PA66 were synthesised and equimolar N detection of CLND to synthesised oligomers, caprolactam, 6-aminohexanoic acid (monomers of PA6) and caffeine (a typical nitrogen calibrant) was proven. Relative response factors (UVD at 210 nm) referring to caprolactam were determined for cyclic PA6 oligomers from dimer to nonamer, using HPLC-CLND in combination with a UVD. A method for quantification of cyclic oligomer content in PA materials was introduced using HPLC-CLND analysis and caffeine as a single nitrogen calibrant. The method was applied to the quantification of cyclic PA oligomers in several PA granulates. For two PA6 granulates from different manufacturers markedly different oligomer contents were analysed (19.5 versus 13.4 g kg⁻¹). The elution pattern of cyclic oligomers offers the possibility of identifying the PA type and differentiating between PA copolymers and blends.

  19. 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

  20. 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

  1. 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.

  2. Studies on Log Po/w of Quinoxaline di-N-Oxides: A Comparison of RP-HPLC Experimental and Predictive Approaches

    Directory of Open Access Journals (Sweden)

    James A. Platts

    2011-09-01

    Full Text Available As reported in our previous papers, a series of quinoxaline-2-carboxamide 1,4-di-N-oxide derivatives were synthesized and studied as anti-tuberculosis agents. Here, the capability of the shake-flask method was studied and the retention time (expressed as log K of 20 compounds were determined by RP-HPLC analysis. We found that the prediction of log P by the RP-HPLC analysis can result in a high accuracy and can replace the shake-flask method avoiding the experimental problems presented by quinoxaline di-N-oxides. The studied compounds were subjected to the ALOGPS module with the aim of comparing experimental log Po/w values and predicted data. Moreover, a preliminary in silico screening of the QSAR relationship was made confirming the influence of reduction peak potential, lipophilicity, H-bond donor capacity and molecular dimension descriptors on anti-tuberculosis activity.

  3. 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

  4. 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.

  5. Simultaneous RP-HPLC Estimation of Cefpodoxime Proxetil and Clavulanic Acid in Tablets

    Science.gov (United States)

    Malathi, S.; Dubey, R. N.; Venkatnarayanan, R.

    2009-01-01

    A new, simple, precise, rapid and accurate RP-HPLC method has been developed for the simultaneous estimation of cefpodoxime proxetil and clavulanic acid from pharmaceutical dosage forms. The method was carried out on a Zorbax Eclipse XDB 5 μ C 18 (150×4.6 mm) column with a mobile phase consisting of acetonitrile:50 mM potassium dihydrogen phosphate buffer (pH 3.0, 70:30 v/v) at a flow rate of 1.0 ml/min. Detection was carried out at 228 nm. Aspirin was used as an internal standard. The retention time of clavulanic acid, cefpodoxime proxetil and aspirin was 4.43, 6.44 and 5.6 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms. PMID:20177474

  6. Simultaneous RP-HPLC estimation of cefpodoxime proxetil and clavulanic acid in tablets

    Directory of Open Access Journals (Sweden)

    Malathi S

    2009-01-01

    Full Text Available A new, simple, precise, rapid and accurate RP-HPLC method has been developed for the simultaneous estimation of cefpodoxime proxetil and clavulanic acid from pharmaceutical dosage forms. The method was carried out on a Zorbax Eclipse XDB 5 µ C 18 (150x4.6 mm column with a mobile phase consisting of acetonitrile:50 mM potassium dihydrogen phosphate buffer (pH 3.0, 70:30 v/v at a flow rate of 1.0 ml/min. Detection was carried out at 228 nm. Aspirin was used as an internal standard. The retention time of clavulanic acid, cefpodoxime proxetil and aspirin was 4.43, 6.44 and 5.6 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms.

  7. Extraction optimization of coumarins from radix angelicae pubescentis by HPLC-DAD coupled with uniform design

    Institute of Scientific and Technical Information of China (English)

    GUO Fang-qiu; HUANG Lan-fang; ZHOU Huo-fei; JIANG Qiu-ju

    2006-01-01

    Uniform design was used to optimize extraction condition of direct refluence extraction of coumarins from the Chinese traditional medicine of radix angelicae pubescentis(Duhuo); the sum peak area of coumarins separated with high performance liquid chromatography(HPLC) at detection wavelength of 320 nm was considered as detection index, two factors of solvent concentration and extraction time were mainly studied at extraction temperature of 85 ℃ and a volume ratio of solvent to sample of 10: 1. Optimal subclass, quadric polynomial step by step aggression and neural network method were applied to process the experimental results. The results show that the first and second methods give the same factors combination (concentration of ethanol: 95 %, extraction time: 3.6 h) and the second method is much better than the first one. The extraction model is consequently developed.

  8. 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: ...

  9. 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.

  10. 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.

  11. 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

    -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.

  12. 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.

  13. 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...

  14. 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.

  15. 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

  16. 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.

  17. Comprehensive chemical analysis of Schisandra chinensis by HPLC-DAD-MS combined with chemometrics.

    Science.gov (United States)

    Liu, Haitao; Lai, Hongwu; Jia, Xinyue; Liu, Jiushi; Zhang, Zhao; Qi, Yaodong; Zhang, Jin; Song, Junbin; Wu, Chongming; Zhang, Bengang; Xiao, Peigen

    2013-09-15

    The fruit of Schisandra chinensis, namely "Wuweizi" in China, is a well-known herbal medicine and health food. In this paper, an accurate and reliable high performance liquid chromatography coupled with diode array detection and mass spectrometry was developed for quality evaluation of Wuweizi. Nine lignans, including schisandrol A, schisandrol B, angeloylgomisin H, gomisin G, schisantherin A, schisanhenol, schisandrin A, schisandrin B, and schisandrin C were determined simultaneously in forty-three batches of Wuweizi samples collected from different localities. Thirty-six common peaks were unequivocally identified or tentatively assigned by comparing their mass spectrometric data with reference compounds, self-established compound library and published literatures. And the thirty-six common peaks were selected as characteristic peaks to assess the similarity of chromatographic fingerprinting of these Wuweizi samples. Moreover, hierarchical clustering analysis and principal components analysis were successfully applied to demonstrate the variability of these Wuweizi samples. The results indicated the content of nine investigated lignans varied greatly among the samples, and samples collected from different localities could be discriminated. Furthermore, schisandrol A, schisandrol B, schisandrin B, and schisandrin C were found to chemical marker for evaluating the quality of Wuweizi.

  18. 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

  19. 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.

  20. Biological warfare agents

    Directory of Open Access Journals (Sweden)

    Duraipandian Thavaselvam

    2010-01-01

    Full Text Available The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  1. 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.

  2. 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....

  3. 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.

  4. Contrast Agent in Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Vu-Quang, Hieu

    2015-01-01

    for chemotherapy. The nanoparticles were 150 nm in size with spherical shape, which contained PFOB in the inner core and Dox and ICG in the polymeric shell. More importantly, they could target folate receptor expressing cancer cells, which provide positive in vitro and in vivo NIR and 19F MRI results. In project......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...

  5. Ontology-based multi-agent systems

    Energy Technology Data Exchange (ETDEWEB)

    Hadzic, Maja; Wongthongtham, Pornpit; Dillon, Tharam; Chang, Elizabeth [Digital Ecosystems and Business Intelligence Institute, Perth, WA (Australia)

    2009-07-01

    The Semantic web has given a great deal of impetus to the development of ontologies and multi-agent systems. Several books have appeared which discuss the development of ontologies or of multi-agent systems separately on their own. The growing interaction between agents and ontologies has highlighted the need for integrated development of these. This book is unique in being the first to provide an integrated treatment of the modeling, design and implementation of such combined ontology/multi-agent systems. It provides clear exposition of this integrated modeling and design methodology. It further illustrates this with two detailed case studies in (a) the biomedical area and (b) the software engineering area. The book is, therefore, of interest to researchers, graduate students and practitioners in the semantic web and web science area. (orig.)

  6. Competing intelligent search agents in global optimization

    Energy Technology Data Exchange (ETDEWEB)

    Streltsov, S.; Vakili, P. [Boston Univ., MA (United States); Muchnik, I. [Rutgers Univ., Piscataway, NJ (United States)

    1996-12-31

    In this paper we present a new search methodology that we view as a development of intelligent agent approach to the analysis of complex system. The main idea is to consider search process as a competition mechanism between concurrent adaptive intelligent agents. Agents cooperate in achieving a common search goal and at the same time compete with each other for computational resources. We propose a statistical selection approach to resource allocation between agents that leads to simple and efficient on average index allocation policies. We use global optimization as the most general setting that encompasses many types of search problems, and show how proposed selection policies can be used to improve and combine various global optimization methods.

  7. 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.)

  8. Insights on the mechanism for synthesis of methylenedianiline from aniline and formaldehyde through HPLC-MS and isotope tracer studies

    Institute of Scientific and Technical Information of China (English)

    Chen Ye Wang; Hui Quan Li; Li Guo Wang; Yan Cao; Hai Tao Liu; Yi Zhang

    2012-01-01

    The mechanism for synthesis of 4,4-methylenedianiline (MDA) via condensation reaction of aniline with formaldehyde has been studied extensively in this paper.The intermediate and by-products were isolated and identified.The combination of isotope labeling and HPLC-MS characterizations disclosed that the reaction proceeded through an SN2 reaction mechanism.Moreover,the effect of aniline/formaldehyde molar ratio on the formation of MDA was investigated.This work would be of significance to understand the reaction mechanism deeply and provide valuable information for further improving the yield of desired product.

  9. 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

  10. Authentication of Cassia seeds on the basis of two-wavelength HPLC fingerprinting with the use of chemometrics

    Institute of Scientific and Technical Information of China (English)

    Serge; Kokot

    2010-01-01

    High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets were combined into one matrix.The application of principal component analysis(PCA) for this data matrix showed that the samples were clustered into four groups in accordance with the plant sources and preparation procedures.Furthermore,partial least squares(PLS),back propagation artificial neu...

  11. 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.

  12. Clinical Evaluation of Mesalamine Combined with Live Bacterial Agent of Bifidobacterium, Lactobacillus, Enterococcus and Bacillus Cereus for Ulcerative Colitis%美沙拉嗪联合双歧杆菌四联活菌治疗溃疡性结肠炎的临床效果评价

    Institute of Scientific and Technical Information of China (English)

    歧红阳; 王云溪; 肖占宇

    2011-01-01

    目的 研究美沙拉嗪联合双歧杆菌四联活菌在治疗溃疡性结肠炎中的临床效果。方法 选取50例溃疡性结肠炎病人,分为2组,试验组27例,给予美沙拉嗪及双歧杆菌四联活菌;对照组23例,给予美沙拉嗪。观察2组患者治愈率及治疗前后的患者血清中自细胞介素-8(IL-8)水平。结果 试验组治愈率(92.6%)明显高于对照组(78.3%),经比较差异有统计学意义(P<0.05),试验组和对照组治疗14 d后,IL-8水平明显低于治疗前,两者相比,差异有统计学意义(P<0.05)。结论 美沙拉嗪联合双歧杆菌四联活菌可提高溃疡性结肠炎的治愈率,且不良反应少,为临床治疗提供思路。%[Objective]To study the clinical effect of mesalamine combined with live bacterial agent of bifidobacterium, lactobacil-lus, enterococcus and bacillus cereus for ulcerative colitis. [ Methods ] 50 patients with ulcerative colitis were randomly divided into the research group (27 cases) and the control group (23 cases). The research group was given mesalamine combined with live bacterial agent of bifidobacterium, lactobacillus, enterococcus and bacillus cereus, and the control group was treated with mesalamine. The cure rate and IL-8 level in serum of patients before and after treatment were observed. [ Results ] The cure rate of the research group (92.6% ) was higher than that of the control group (78.3% ) significantly (P<0.05). After 14 days of treatment, and the IL-8 level of two groups was significantly lower than before treatment (P <0.05). [ Conclusion] Mesalamine combined with live bacterial agent of bifidobacterium, lactobacillus, enterococcus and bacillus cereus can improve the cure rate of ulcerative colitis, and with less adverse reaction, which provides a new idea for clinical therapy.

  13. Agent Standards Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation of the work herein proposed is the development of standards for software autonomous agents. These standards are essential to achieve software...

  14. Development and Validation of an HPLC Method for Simultaneous Determination of Rifampicin, Isoniazid, Pyrazinamide, and Ethambutol Hydrochloride in Pharmaceutical Formulations.

    Science.gov (United States)

    Chellini, Paula R; Lages, Eduardo B; Franco, Pedro H C; Nogueira, Fernando H A; César, Isabela C; Pianetti, Gerson A

    2015-01-01

    Tuberculosis treatment consists of a fixed dose combination of rifampicin (RIF), isoniazid (INH), pyrazinamide (PYZ), and ethambutol hydrochloride (EMB). The combined treatment using various drugs is necessary for patient curing, without recrudescence, and for prevention of drug-resistant mutants, which may occur during treatment. An HPLC-diode array detector (DAD) method for the simultaneous determination of RIF, INH, PYZ, and EMB in fixed dose combination tablets was developed and validated. Chromatographic experiments were performed on an Agilent 1200 HPLC system, and the separation was carried out on a Purospher STAR RP18e (250×4.6 mm id, 5 μm, Merck) analytical column. Gradient elution was carried out with a mobile phase of 20 mM monobasic sodium phosphate buffer with 0.2% triethylamine (pH 7.0) and acetonitrile at a flow rate of 1.5 mL/min. The total run time was 12 min, and the re-equilibration time was 5 min. EMB detection was performed at 210 nm, and RIF, INH, and PYZ were detected at 238 nm, using a DAD. The method proved to be specific, linear (r2>0.99), precise (RSD<2%), accurate, and robust and may be applied to the QC analysis of pharmaceutical formulations. PMID:26525241

  15. Development and validation of RP-HPLC method to determine anti-allergic compound in Thai traditional remedy called Benjalokawichien.

    Science.gov (United States)

    Sakpakdeejaroen, Intouch; Juckmeta, Thana; Itharat, Arunporn

    2014-08-01

    Benjalokawichien (BLW) or Ya-Ha-Rak (HR) is a traditional remedy in the Nationaldrug list of herbal medicinal products AD 2012 of Thailand. For traditional use, BLW is used as antipyretic agent. It also has anti-allergic effect, particularly treating allergic rash. The ethanolic extract of BLW exhibited anti-allergic activity via inhibitory effect against a release ofbeta-hexosaminidase in RBL-2H3 cell line. Pectolinarigenin has been identified as the active compound ofBLW extract. In this study, a reversed-phase high performance liquid chromatography (RP-HPLC) method was developed in order to control quality ofpreparation in three aspects such as chemical fingerprint, quantification and stability of the ethanolic extract. The RP-HPLC was performed with a gradient mobile phase composed of 0.1% ortho phosphoric acid and acetronitrile, and peaks were detected at 331 nm. Based on validation results, this analytical method is precise, accurate and stable for quantitative determination ofpectolinarigenin. The amount ofpectolinarigenin in Benjalokawichien extract determined by this method was 18.50 mg/g ofextract. Therefore, this method could be consideredfor quality control ofBLWextract. PMID:25518297

  16. 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) ...

  17. 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.

  18. 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 ...

  19. 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

  20. 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.

  1. 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%.

  2. 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

  3. HPLC analysis of phenolics compounds and antioxidant capacity of leaves of Vitex megapotamica (Sprengel) Moldenke.

    Science.gov (United States)

    de Brum, Thiele Faccim; Zadra, Marina; Piana, Mariana; Boligon, Aline Augusti; Fröhlich, Janaina Kieling; de Freitas, Robson Borba; Stefanello, Sílvio Terra; Froeder, Amanda Luana Forbrig; Belke, Bianca Vargas; Nunes, Letícia Teixeira; da Silva Jesus, Roberta; Machado, Michel Mansur; da Rocha, João Batista Teixeira; Soares, Félix Alexandre Antunes; Athayde, Margareth Linde

    2013-07-16

    Vitex megapotamica (Sprengel) Moldenke belongs to the Verbenaceae family and is popularly known as "tarumã". The antioxidant capacity of fractions and crude extract from the leaves of V. megapotamica were determined in this study through the capacity to remove reactive species and phenolic compounds were quantified in the various fractions. The IC50 (DPPH) ranged from 14.17 ± 0.76 to 37.63 ± 0.98 µg/mL. The ethyl acetate fraction might contain the strongest lipid peroxidation inhibitory compounds with an IC50 of 16.36 ± 5.09 µg/mL, being also the one with the highest content of polyphenols (522.4 ± 1.12 mg/g), flavonoids (220.48 ± 0.30 mg/g) and condensed tannins (3.86 ± 0.53 mg/g). Compounds quantified by HPLC/DAD in the crude extract and fractions were chlorogenic and rosmarinic acids. Higher dosages of the extracts were more effective in reducing levels of plasma protein carbonyls and were also shown to be able to remove reactive species by a 2',7'-dichlorofluorescein diacetate assay, reducing oxidative stress in all tested fractions. Results obtained indicated that V. megapotamica exhibits good potential to prevent diseases caused by the overproduction of free radicals and it might also be used as a potential source of natural antioxidant agents.

  4. HPLC Analysis of Phenolics Compounds and Antioxidant Capacity of Leaves of Vitex megapotamica (Sprengel Moldenke

    Directory of Open Access Journals (Sweden)

    Félix Alexandre Antunes Soares

    2013-07-01

    Full Text Available Vitex megapotamica (Sprengel Moldenke belongs to the Verbenaceae family and is popularly known as “tarumã”. The antioxidant capacity of fractions and crude extract from the leaves of V. megapotamica were determined in this study through the capacity to remove reactive species and phenolic compounds were quantified in the various fractions. The IC50 (DPPH ranged from 14.17 ± 0.76 to 37.63 ± 0.98 µg/mL. The ethyl acetate fraction might contain the strongest lipid peroxidation inhibitory compounds with an IC50 of 16.36 ± 5.09 µg/mL, being also the one with the highest content of polyphenols (522.4 ± 1.12 mg/g, flavonoids (220.48 ± 0.30 mg/g and condensed tannins (3.86 ± 0.53 mg/g. Compounds quantified by HPLC/DAD in the crude extract and fractions were chlorogenic and rosmarinic acids. Higher dosages of the extracts were more effective in reducing levels of plasma protein carbonyls and were also shown to be able to remove reactive species by a 2',7'-dichlorofluorescein diacetate assay, reducing oxidative stress in all tested fractions. Results obtained indicated that V. megapotamica exhibits good potential to prevent diseases caused by the overproduction of free radicals and it might also be used as a potential source of natural antioxidant agents.

  5. 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

  6. 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

  7. 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

  8. 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.

  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. HPLC-DAD-MS identification of bioactive secondary metabolites from Ferula communis roots.

    Science.gov (United States)

    Arnoldi, Lolita; Ballero, Mauro; Fuzzati, Nicola; Maxia, Andrea; Mercalli, Enrico; Pagni, Luca

    2004-06-01

    A simple HPLC method was developed to distinguish between 'poisonous' and 'non-poisonous' chemotypes of Ferula communis. The method was performed on a C8 reverse phase analytical column using a binary eluent (aqueous TFA 0.01%-TFA 0.01% in acetonitrile) under gradient condition. The two chemotypes showed different fingerprints. The identification of five coumarins and eleven daucane derivatives by HPLC-diode array detection (HPLC-DAD) and HPLC-MS is described. A coumarin, not yet described, was detected.

  11. 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...

  12. 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...

  13. 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

  14. 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...

  15. 应用HPLC-FLD法测定食品中的糖精钠%Determining saccharin sodium by HPLC -FLD

    Institute of Scientific and Technical Information of China (English)

    费贤明; 张红梅

    2007-01-01

    目的:建立一种准确测定食品中糖精钠的方法.方法:采用HPLC-FLD法测定.结果:糖精钠的最低检测限为1.1 ng,回收率为97%,浓度为0.005~0.20 mg/ml时线性良好.结论:方法简单灵敏、准确度高,更适于糖精钠的测定.

  16. Multi-agent based cooperative search in combinatorial optimisation

    OpenAIRE

    Martin, Simon

    2013-01-01

    Cooperative search provides a class of strategies to design more effective search methodologies by combining (meta-) heuristics for solving combinatorial optimisation problems. This area has been little explored in operational research. This thesis proposes a general agent-based distributed framework where each agent implements a (meta-) heuristic. An agent continuously adapts itself during the search process using a cooperation protocol based on reinforcement learning and pattern matching. G...

  17. Study on synergy of fosfomycin combined with 4 kinds of antimicrobial agents against Pseudomonas aeruginosa strains i-solated from urinary system%磷霉素与4种抗菌药物对泌尿系统分离铜绿假单胞菌的协同作用研究

    Institute of Scientific and Technical Information of China (English)

    黄正谷; 苏世芳

    2015-01-01

    Objective To study the in vitro antibacterial activity of fosfomycin combined with other 4 kinds of antimicrobial agents against 40 clinically isolated strains of Pseudomonas aeruginosa .Methods The bacteria were i‐solated and identified by the conventional culture and the microbiological analyzer .The drug sensitive test was per‐formed by using Kirby‐Bauer disk diffusion test and the minimal inhibitory concentration (MIC) was examined by u‐sing the agar double dilution test and the micrdilution checkerboard technique .The fractional inhibitory concentration index(FICI) was calculated .Results A total of 40 strains of Pseudomonas aeruginosa were resistant to most of anti‐bacterial agents .The fosfomycin exclusive use had a good antibacterial activity to Pseudomonas aeruginosa and the re ‐sistance rate was 37 .5% ;the combination use of fosfomycin with 4 kinds of antimicrobial agent showed the addictive action and independent action ,little synergic effect and no antagonism .Conclusion Fosfomycin is still a choice of an‐tibacterial drugs to treat the urinary tract infection induced by Pseudomonas aeruginosa .%目的:研究磷霉素与4种抗菌药物分别联合应用对40株临床分离铜绿假单胞菌的体外抗菌活性。方法采用常规培养方法和微生物分析仪对细菌进行分离、鉴定。采用 K‐B 纸片扩散法进行药敏试验。采用琼脂倍比稀释法和微量棋盘法测定最低抑菌浓度(MIC),计算部分抑菌浓度指数(FICI)。结果40株铜绿假单胞菌对大多数抗菌药物具有耐药性。磷霉素单独使用对铜绿假单胞菌具有较好的抗菌活性,耐药率为37.5%;磷霉素与4种抗菌药物联用后,对铜绿假单胞菌表现为相加和无关作用,协同作用较少,未见拮抗作用。结论治疗铜绿假单胞菌引起的泌尿系统感染,磷霉素仍是一个可供选择的抗菌药物。

  18. Pungency Quantitation of Hot Pepper Sauces Using HPLC

    Science.gov (United States)

    Betts, Thomas A.

    1999-02-01

    A class of compounds known as capsaicinoids are responsible for the "heat" of hot peppers. To determine the pungency of a particular pepper or pepper product, one may quantify the capsaicinoids and relate those concentrations to the perceived heat. The format of the laboratory described here allows students to collectively develop an HPLC method for the quantitation of the two predominant capsaicinoids (capsaicin and dihydrocapsaicin) in hot-pepper products. Each small group of students investigated one of the following aspects of the method: detector wavelength, mobile-phase composition, extraction of capsaicinoids, calibration, and quantitation. The format of the lab forced students to communicate and cooperate to develop this method. The resulting HPLC method involves extraction with acetonitrile followed by solid-phase extraction clean-up, an isocratic 80:20 methanol-water mobile phase, a 4.6 mm by 25 cm C-18 column, and UV absorbance detection at 284 nm. The method developed by the students was then applied to the quantitation of capsaicinoids in a variety of hot pepper sauces. Editor's Note on Hazards in our April 2000 issue addresses the above.

  19. 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.

  20. 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

  1. Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    Dev Vrat Kamboj

    2006-10-01

    Full Text Available There is a long historic record of use of biological warfare (BW agents by warring countriesagainst their enemies. However, the frequency of their use has increased since the beginningof the twentieth century. World war I witnessed the use of anthrax agent against human beingsand animals by Germans, followed by large-scale field trials by Japanese against war prisonersand Chinese population during world war II. Ironically, research and development in biologicalwarfare agents increased tremendously after the Geneva Protocol, signed in 1925, because ofits drawbacks which were overcome by Biological and Toxin Weapons Convention (BTWC in1972. Biological warfare programme took back seat after the 1972 convention but biologicalagents regained their importance after the bioterrorist attacks of anthrax powder in 2001. In thelight of these attacks, many of which turned out to be hoax, general awareness is required aboutbiological warfare agents that can be used against them. This review has been written highlightingimportant biological warfare agents, diseases caused by them, possible therapies and otherprotection measures.

  2. Agent Oriented Programming进展%Advances in Agent Oriented Programming

    Institute of Scientific and Technical Information of China (English)

    王一川; 石纯一

    2002-01-01

    Agent-oriented programming (AOP) is a framework to develop agents, and it aims to link the gap betweentheory and practical in agent research. The core of an AOP framework is its language and semantics. In this paper,we propose the necessary properties which agents should have, and then give a summary and analysis about differentAOP languages based on these properties.

  3. Developing Enculturated Agents

    DEFF Research Database (Denmark)

    Rehm, Matthias

    2010-01-01

    on our cultural profiles that provide us with heuristics of behavior and interpretation. Thus, integrating cultural aspects of communicative behaviors in virtual agents and thus enculturating such systems seems to be inevitable. But culture is a multi-defined domain and thus a number of pitfalls arise......Embodied Conversational Agents (ECAs) are complex multimodal systems with rich verbal and nonverbal repertoires. There human-like appearance raises severe expectations regarding natural communicative behaviors on the side of the user. But what is regarded as “natural” is to a large degree dependent...... that have to be avoided in the endeavor. This chapter presents some of the pitfalls for enculturating interactive systems and presents strategies on how to avoid these pitfalls in relation to the standard development process of Embodied Conversational Agents....

  4. Agents unleashed a public domain look at agent technology

    CERN Document Server

    Wayner, Peter

    1995-01-01

    Agents Unleashed: A Public Domain Look at Agent Technology covers details of building a secure agent realm. The book discusses the technology for creating seamlessly integrated networks that allow programs to move from machine to machine without leaving a trail of havoc; as well as the technical details of how an agent will move through the network, prove its identity, and execute its code without endangering the host. The text also describes the organization of the host's work processing an agent; error messages, bad agent expulsion, and errors in XLISP-agents; and the simulators of errors, f

  5. Agent-oriented Single Token and Colored Transition Petri Net

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Petri net is a kind of effective graphic modeling tool. The agent technology is combined with petri net in order to enhance flexibility and extendibility, and the agent-oriented single token and colored transition petri net is proposed. Some characteristics such as liveness, fairness and safety are analyzed. Finally, an example in mould agile manufacturing is given to illustrate the use of it.

  6. Access Control for Agent-based Computing: A Distributed Approach.

    Science.gov (United States)

    Antonopoulos, Nick; Koukoumpetsos, Kyriakos; Shafarenko, Alex

    2001-01-01

    Discusses the mobile software agent paradigm that provides a foundation for the development of high performance distributed applications and presents a simple, distributed access control architecture based on the concept of distributed, active authorization entities (lock cells), any combination of which can be referenced by an agent to provide…

  7. El agente encubierto

    OpenAIRE

    Anaya Marcos, María del Carmen

    2015-01-01

    [ES] El trabajo versa sobre la figura del agente encubierto. Debemos enmarcar tal medida de investigación dentro del ámbito de la criminalidad organizada. Actualmente, estamos asistiendo a una proliferación de la delincuencia organizada. La sociedad ha evolucionado, y con ella la delincuencia. Fruto de tal evolución fue necesario incluir en nuestra Ley de Enjuiciamiento Criminal medidas extraordinarias de investigación, y una de ellas es el agente encubierto. Se trata de una medida muy polémi...

  8. Determination of anthocyanins from camu-camu (Myrciaria dubia) by HPLC-PDA, HPLC-MS, and NMR.

    Science.gov (United States)

    Zanatta, Cinthia Fernanda; Cuevas, Elyana; Bobbio, Florinda O; Winterhalter, Peter; Mercadante, Adriana Z

    2005-11-30

    Camu-camu [Myrciaria dubia (HBK) McVaugh] is a small fruit native to the Amazonian rain forest. Its anthocyanin profile has now been investigated for the first time. Fruits from two different regions of the São Paulo state, Brazil, were analyzed. The major anthocyanins were isolated by high-speed countercurrent chromatography. HPLC-PDA, HPLC-MS/MS, and 1H NMR were used to confirm the identity of the main anthocyanins of camu-camu. Cyanidin-3-glucoside was identified as the major pigment in the fruits from both regions, representing 89.5% in the fruits produced in Iguape and 88.0% in those from Mirandópolis, followed by the delphinidin-3-glucoside, ranging between 4.2 and 5.1%, respectively. Higher total anthocyanin contents were detected in the fruits from Iguape (54.0 +/- 25.9 mg/100 g) compared to those from Mirandópolis (30.3 +/- 6.8 mg/100 g), most likely because of the lower temperatures in the Iguape region. PMID:16302773

  9. Programming multi-agent systems

    NARCIS (Netherlands)

    Dastani, Mehdi

    2015-01-01

    With the significant advances in the area of autonomous agents and multi-agent systems in the last decade, promising technologies for the development and engineering of multi-agent systems have emerged. The result is a variety of agent-oriented programming languages, development frameworks, executio

  10. Software Agent Techniques in Design

    DEFF Research Database (Denmark)

    Hartvig, Susanne C

    1998-01-01

    This paper briefly presents studies of software agent techniques and outline aspects of these which can be applied in design agents in integrated civil engineering design environments.......This paper briefly presents studies of software agent techniques and outline aspects of these which can be applied in design agents in integrated civil engineering design environments....

  11. Trading Agents for Roaming Users

    OpenAIRE

    Boman, Magnus; Bylund, Markus; Espinoza, Fredrik; Danielson, Mats; Lyback, David

    2002-01-01

    Some roaming users need services to manipulate autonomous processes. Trading agents running on agent trade servers are used as a case in point. We present a solution that provides the agent owners with means to upkeeping their desktop environment, and maintaining their agent trade server processes, via a briefcase service.

  12. 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

  13. Analysis of brominated and phosphate-based flame retardants in polymer samples by HPLC-UV/MS and online-GPC-HPLC-UV

    Energy Technology Data Exchange (ETDEWEB)

    Schlummer, M.; Brandl, F. [Fraunhofer-Institut fuer Verfahrenstechnik und Verpackung (IVV), Freising (Germany); Maeurer, A.

    2004-09-15

    Here we present two analytical approaches for the identification and quantification of brominated and phosphate-based flame retardants. The first is an HPLC-UV/MS approach, which allows the separation and unequivocal identification and quantification of at least 15 different technical flame retardants. The second approach was set-up as a screening tool, consisting of a GPC separation coupled to an HPLC-UV device.

  14. 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

  15. Agents of Change

    DEFF Research Database (Denmark)

    Hansen, Jens Aage; Lehmann, Martin

    2004-01-01

    at large, it emphasises universities as key change agents and providers in new learning, including tools such as project based and problem oriented learning (PBL) as well as information and communication technology (ICT); as providers of competent and motivated graduates to fill key positions in society...

  16. Programming Agents with Emotions

    NARCIS (Netherlands)

    Dastani, Mehdi; Floor, Chr.; Meyer, John-Jules Charles

    2014-01-01

    In this paper we show how a cognitive agent programming language can be endowed with ways to program emotions. In particular we show how the programming language 2APL can be augmented so that it can work together with the computational emotion model ALMA to deal with appraisal, emotion/mood generati

  17. The need for agents

    DEFF Research Database (Denmark)

    Abolfazlian, Ali Reza Kian

    1996-01-01

    I denne artikel arbejder vi med begrebet Intelligent Software Agents (ISAs), som autonomous, social, reactive, proactive og subservient computer systemer. Baseret på socialt psykologiske argumenter viser jeg endvidere, hvordan både den menneskelige natur og det teknologiske stadium, som mennesket...

  18. SECOND BUYING AGENT

    CERN Multimedia

    SPL - SERVICES ACHATS

    2000-01-01

    Last year the buying agent LOGITRADE started operations on the CERN site, processing purchasing requests for well-defined families of products up to a certain value. It was planned from the outset that a second buying agent would be brought in to handle the remaining product families. So, according to that plan, the company CHARLES KENDALL will be commencing operations at CERN on 8 May 2000 in Building 73, 1st floor, offices 31 and 35 (phone and fax numbers to be announced).Each buying agent will have its own specific list of product families and will handle purchasing requests up to 10'000 CHF.Whenever possible they will provide the requested supplies at a price (including the cost of their own services) which must be equivalent to or lower than the price mentioned on the purchasing request, changing the supplier if necessary. If a lower price cannot be obtained, agents will provide the necessary administrative support free of charge.To ensure that all orders are processed in the best possible conditions, us...

  19. Identification and Determination of Nicorandil and its Degradation Products by HPLC and GC/MS

    Institute of Scientific and Technical Information of China (English)

    Zhong Zhou CHENG; Ze Hui JIA; Yan CHEN; Li Ying CHEN; Hua LI

    2006-01-01

    A rapid and sensitive HPLC-DAD method is developed for simultaneous determination of nicorandil and its degradation products, N-(2-hydroxyethyl) nicotinamide, nitrate ion and nicotinic acid, using nicotinamide (NT) as internal standard, at wavelength 204 nm. Nicotinic acid is identified by HPLC and GC/MS. The method can also be applied to study kinetic of degradation processes of nicorandil in storage.

  20. 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 ...