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Sample records for agent combining hplc

  1. Cell extraction combined with off-line HPLC for screening active compounds from Coptis chinensis.

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    Tang, Cheng; Wu, Xiao-Dan; Yu, Ya-Ming; Duan, Hongquan; Zhou, Jing; Xu, Liang

    2016-04-01

    Cell membrane chromatography is a useful tool for screening active compounds from natural products. As the reason of separation mechanism, traditional cell membrane chromatography could not be used for screening the active compounds absorbed through the cell membrane and influencing the cell signal transduction pathway. In this work, we establish a new method named cell extraction combined with off-line HPLC for screening the compounds penetrating the cell membrane. This is the first time 3 T3-L1 adipocyte culture has been combined with HPLC technology. Compared with other cell membrane chromatography methods, there is good resolution and no further analysis by other chromatographic steps is required. On co-incubating crude extracts of Coptis chinensis with cells and analyzing the compounds extracted by the cells, active compounds such as berberine were detected. Glucose consumption tests showed that berberine could increase glucose consumption by insulin-resistant 3 T3-L1 adipocytes. The levels of intracellular berberine correlated with its activity. The results indicate that the developed method could be an alternative method for screening active compounds from natural products.

  2. Discrimination of red and white rice bran from Indonesia using HPLC fingerprint analysis combined with chemometrics.

    Science.gov (United States)

    Sabir, Aryani; Rafi, Mohamad; Darusman, Latifah K

    2017-04-15

    HPLC fingerprint analysis combined with chemometrics was developed to discriminate between the red and the white rice bran grown in Indonesia. The major component in rice bran is γ-oryzanol which consisted of 4 main compounds, namely cycloartenol ferulate, cyclobranol ferulate, campesterol ferulate and β-sitosterol ferulate. Separation of these four compounds along with other compounds was performed using C18 and methanol-acetonitrile with gradient elution system. By using these intensity variations, principal component and discriminant analysis were performed to discriminate the two samples. Discriminant analysis was successfully discriminated the red from the white rice bran with predictive ability of the model showed a satisfactory classification for the test samples. The results of this study indicated that the developed method was suitable as quality control method for rice bran in terms of identification and discrimination of the red and the white rice bran.

  3. Geographical classification of Epimedium based on HPLC fingerprint analysis combined with multi-ingredients quantitative analysis.

    Science.gov (United States)

    Xu, Ning; Zhou, Guofu; Li, Xiaojuan; Lu, Heng; Meng, Fanyun; Zhai, Huaqiang

    2017-05-01

    A reliable and comprehensive method for identifying the origin and assessing the quality of Epimedium has been developed. The method is based on analysis of HPLC fingerprints, combined with similarity analysis, hierarchical cluster analysis (HCA), principal component analysis (PCA) and multi-ingredient quantitative analysis. Nineteen batches of Epimedium, collected from different areas in the western regions of China, were used to establish the fingerprints and 18 peaks were selected for the analysis. Similarity analysis, HCA and PCA all classified the 19 areas into three groups. Simultaneous quantification of the five major bioactive ingredients in the Epimedium samples was also carried out to confirm the consistency of the quality tests. These methods were successfully used to identify the geographical origin of the Epimedium samples and to evaluate their quality.

  4. Combinative Method Using Multi-components Quantitation and HPLC Fingerprint for Comprehensive Evaluation of Gentiana crassicaulis

    Science.gov (United States)

    Song, Jiuhua; Chen, Fengzheng; Liu, Jiang; Zou, Yuanfeng; Luo, Yun; Yi, Xiaoyan; Meng, Jie; Chen, Xingfu

    2017-01-01

    Background: Gentiana crassicaulis () is an important traditional Chinese herb. Like other herbs, its chemical compounds vary greatly by the environmental and genetic factors, as a result, the quality is always different even from the same region, and therefore, the quality evaluation is necessary for its safety and effective use. In this study, a comprehensive method including HPLC quantitative analysis and fingerprints was developed to evaluate the quality of Cujingqinjiao and to classify the samples collected from Lijiang City of Yunnan province. A total of 30 common peaks including four identified peaks, were found, and were involved for further characterization and quality control of Cujingqinjiao. Twenty-one batches of samples from Lijiang City of Yunnan Province were evaluated by similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA) and factor analysis (FA) according to the characteristic of common peaks. Results: The obtained data showed good stability and repeatability of the chromatographic fingerprint, similarity values were all more than 0.90. This study demonstrated that a combination of the chromatographic quantitative analysis and fingerprint offered an efficient way to quality consistency evaluation of Cujingqinjiao. Consistent results were obtained to show that samples from a same origin could be successfully classified into two groups. Conclusion: This study revealed that the combinative method was reliable, simple and sensitive for fingerprint analysis, moreover, for quality control and pattern recognition of Cujingqinjiao. SUMMARY HPLC quantitative analysis and fingerprints was developed to evaluate the quality of Gentiana crassicaulisSimilarity analysis, hierarchical cluster analysis, principal component analysis and factor analysis were employed to analysis the chromatographic dataset.The results of multi-components quantitation analysis, similarity analysis, hierarchical cluster analysis, principal

  5. Ibuprofen metabolite profiling using a combination of SPE/column-trapping and HPLC-micro-coil NMR.

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    Djukovic, Danijel; Appiah-Amponsah, Emmanuel; Shanaiah, Narasimhamurthy; Gowda, G A Nagana; Henry, Ian; Everly, Mike; Tobias, Brian; Raftery, Daniel

    2008-06-09

    Solid-phase extraction and column-trapping preconcentration are combined to enhance HPLC-nuclear magnetic resonance (HPLC-NMR) and applied to metabolite profiling in biological samples. Combining the two signal enhancement techniques improved the NMR signal substantially such that we were able to identify 2-hydroxyibuprofen, carboxyibuprofen, and unmetabolized ibuprofen molecules from a small urine sample after a therapeutic dose of ibuprofen. The hyphenated SPE/column-trapping method resulted in an excellent overall signal enhancement of up to 90-fold.

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

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    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. 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.

  8. A novel fluorescence derivatization method combined with HPLC for determining the activities of endogenous caspase.

    Science.gov (United States)

    Liu, Jiachi; Lu, Ye; Liang, Jianying

    2012-11-07

    A novel fluorescence derivatization method combined with HPLC was developed to detect the activity of caspase-3 and -8 in two cell lines (Hela cells and A549 cells) which were activated by low temperature-assisted ultraviolet irradiation (LT-UV), mitomycin C (MMC) and camptothecin during the apoptosis, respectively. Two peptide substrates for either caspase-3 or -8 were designed, of which peptide fragments were obtained by enzymatic modification, followed by fluorescence derivatization. A single fluorescent product was formed when a peptide was heated at 120 °C for 10 min in a neutral aqueous medium (pH 7.0) containing catechol, sodium periodate and sodium borate. Commercial kits for detecting the activity of caspase-3 and -8 were used as a control. The relative activity of the caspases detected by fluorescence derivatization was similar to that obtained by commercial kits, which indicated that the novel method is reliable. The activity assays of recombinant human caspases showed that the novel method provided higher selectivity than that of commercial kits, which proved it to be more accurate for determining the activity of caspases in apoptosis.

  9. Mono- and combined antimicrobial agents efficiency in experimental wound infection

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    Наталія Ігорівна Філімонова

    2015-10-01

    Full Text Available Modern problems of antibiotic therapy are shown by wide range of side effects, both on organism and microbiological levels: the spread of allergies, toxic for organ systems reactions, dysbiosis development, and resistant pathogens formation and dissemination. Therefore the necessity of search for new effective drugs with significant antimicrobial activity applied for the wounds treatment arises. Development of combined remedies on the background of different origin antimicrobial agents’ derivatives is one of the fight directions against infectious diseases in the skin pathology. Recently among the existing antimicrobial agents one should focus on antiseptic drugs, due to degenerative and dysfunctional effect on microbial cell.Aim of research. The comparison of mono- and combined antimicrobial agents chemotherapeutic efficiency in the treatment of localized purulent infection under experimental conditions.Metods. The study of chemotherapeutic efficiency was carried out on the model of localized purulent Staphylococcus infection on albino mice weighting 14 – 16 g. S.aureus ATCC 25923 strains were used as infectious agents. The contamination was performed subcutaneously to the right side of mice’s skin after depilation. The animals were randomly divided into 4 groups: the 1st group – infected mice without treatment (control; the 2nd group – infected mice treated with a ciprofloxacin; the 3rd group – infected mice treated with a Ciprofloxacin and Decamethoxin combination; the 4th group – infected mice treated with a combined drug on the base of mutual prodrugs (Hexamethylenetetramine and Phenyl salicylate.Results. The efficiency of mono- and combined antimicrobial agents under experimental Staphylococcus wound infection conditions was studied. It was found that localized purulent staph center was formed more slowly in comparison with control and mono preparation use (2nd group of animals. The average index of skin lesions in comparison

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

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    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

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

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    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.

  12. Combination therapy with leflunomide and genetic engineering biological agents

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    Nataliya Vladimirovna Chichasova

    2011-06-01

    Full Text Available The paper gives data on the use of a combination of genetic engineering biological agents (GEBAs and leflunomide in patients with rheumatoid arthritis (RA. In accordance with the international guidelines, the majority of GEBAs should be given in a combination with methotrexate (MTX, which increases the efficacy of a number of GEBAs (tumor necrosis factor-α inhibitors, rituximab and affects tolerability (remikeid, humira. However, MTX cannot be always used in real practice. The data given in the paper on the efficiency and safety of the coadministration of leflunomide and a GEBA in patients with active RA, which are based on the results of randomized studies and national registers, including the Russian one, point to the compatibility of the results of treatment with this and GEBA-MTX combinations.

  13. 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

  14. Study on the Alkaloids in Tibetan Medicine Aconitum pendulum Busch by HPLC-MSn Combined with Column Chromatography.

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    Wang, Beibei; Dong, Jie; Ji, Jiaojiao; Yuan, Jiang; Wang, Jiali; Wu, Jiarui; Tan, Peng; Liu, Yonggang

    2016-01-01

    A rapid, convenient and effective identification method of alkaloids was established and an attempt on isolating and analyzing the alkaloids in Aconitum pendulum Busch was conducted successfully. In this article, four high-content components including deoxyaconitine, benzoylaconine, aconine and neoline were isolated by using column chromatography. HPLC-MS(n)was employed to deduce the regulations of fragmentation of diterpenoid alkaloids which displayed a characteristic behavior of loss of CO(28u), CH3COOH(60u), CH3OH(32u), H2O(18u) and C6H5COOH(122u). Then, according to fragmentation regulation of mass spectrometry, 42 alkaloids were found inA. pendulum Among them, 38 compounds were identified and 29 alkaloids were reported for the first time for this herb. Therefore, this means that HPLC-MS(n)combined with column chromatography could work as an effective and reliable tool for rapid identification of the chemical components of herbal medicine.

  15. 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).

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    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

  16. Sacubitril/Valsartan: A Novel Cardiovascular Combination Agent.

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    Sible, Alexandra M; Nawarskas, James J; Alajajian, David; Anderson, Joe R

    2016-01-01

    Sacubitril/valsartan [LCZ696 (Entresto), Novartis Pharmaceuticals Corp.] is the first in a new class of drugs that combines neprilysin inhibition with angiotensin II receptor antagonism, the combination of which acts to increase endogenous natriuretic peptides while inhibiting the renin-angiotensin-aldosterone system. Sacubitril/valsartan has been studied in the treatment of hypertension, heart failure with reduced ejection fraction (HFrEF), and heart failure with preserved ejection fraction (HFpEF) and has demonstrated clinical efficacy in blood pressure reduction in hypertensive patients with and without HFpEF and a reduction in hospitalizations and mortality for patients with HFrEF. Research to evaluate clinical outcomes in HFpEF is ongoing. Sacubitril/valsartan is approved to reduce hospitalization and risk of cardiovascular death for patients with HFrEF in New York Heart Association (NYHA) functional class II-IV. The product is as well tolerated as an angiotensin-converting enzyme inhibitor, with the most common side effect being hypotension. Expectedly, it is much more costly than generic angiotensin-converting enzyme inhibitors or angiotensin receptor antagonists, which will be a factor in determining how widespread the use of this agent will be. In summary, although the number of published studies evaluating its use is limited, sacubitril/valsartan represents a promising new treatment option for patients with HFrEF. Ongoing studies will continue to refine the role of this agent in clinical practice.

  17. Fingerprint analysis of polysaccharides from different Ganoderma by HPLC combined with chemometrics methods.

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    Sun, Xiaomei; Wang, Haohao; Han, Xiaofeng; Chen, Shangwei; Zhu, Song; Dai, Jun

    2014-12-19

    A fingerprint analysis method has been developed for characterization and discrimination of polysaccharides from different Ganoderma by high performance liquid chromatography (HPLC) coupled with chemometrics means. The polysaccharides were extracted under ultrasonic-assisted condition, and then partly hydrolyzed with trifluoroacetic acid. Monosaccharides and oligosaccharides in the hydrolyzates were subjected to pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone and HPLC analysis, which will generate unique fingerprint information related to chemical composition and structure of polysaccharides. The peak data were imported to professional software in order to obtain standard fingerprint profiles and evaluate similarity of different samples. Meanwhile, the data were further processed by hierarchical cluster analysis and principal component analysis. Polysaccharides from different parts or species of Ganoderma or polysaccharides from the same parts of Ganoderma but from different geographical regions or different strains could be differentiated clearly. This fingerprint analysis method can be applied to identification and quality control of different Ganoderma and their products.

  18. Stability indicating RP-HPLC method for simultaneous determination of amlodipine and benazepril hydrochloride from their combination drug product.

    Science.gov (United States)

    Naidu, K Raghu; Kale, Udhav N; Shingare, Murlidhar S

    2005-09-01

    A stability indicating reversed-phase HPLC method has been developed and subsequently validated for simultaneous estimation of amlodipine (AM) present as amlodipine besylate (AB), and benazepril hydrochloride (BH) from their combination product. The proposed RP-HPLC method utilizes a Zorbax SB C18, 5 microm, 250 mm x 4.6 mm i.d. column, mobile phase consisting of phosphate buffer and acetonitrile in the proportion of 65:35 (v/v) with apparent pH adjusted to 7.0, and UV detection at 240 nm using a photodiode array detector. AB, BH, and their combination drug product were exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were analysed by the proposed method. Peak homogeneity data of AM and BH peaks obtained using photodiode array detector, in the stressed sample chromatograms, demonstrated the specificity of the method for their estimation in presence of degradants. The described method was linear over a range of 6-14 microg/ml for AM and 12-28 microg/ml for BH. The mean recoveries were 99.91 and 100.53% for AM and BH, respectively. F-test and t-test at 95% confidence level were used to check the intermediate precision data obtained under different experimental setups; the calculated value was found to be less than critical value.

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

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    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. Chemical fingerprinting of Gardenia jasminoides Ellis by HPLC-DAD-ESI-MS combined with chemometrics methods.

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    Han, Yan; Wen, Jun; Zhou, Tingting; Fan, Guorong

    2015-12-01

    A fingerprint analysis method has been developed for characterization and discrimination of Gardenia jasminoides Ellis from different areas. The chemometrics methods including similarity evaluation, principal components analysis (PCA) and hierarchical clustering analysis (HCA) were introduced to identify more useful chemical markers for improving the quality control standard of dried ripe fruits of G. jasminoides Ellis. Then the selected chemical markers were analyzed by high performance liquid chromatography-diode array detection-electrospray ionization mass spectrometry (HPLC-DAD-ESI-MS) qualitatively and quantitatively. 23 characteristic peaks were assigned while 19 peaks of them were identified by comparing retention times, UV and MS spectra with authentic compounds or literature data. Moreover, 14 of them were determined quantitatively which could effectively evaluate the quality of G. jasminoides Ellis. This study was expected to provide comprehensive information for the quality evaluation of G. jasminoides Ellis, which would be a valuable reference for further study and development of this herb and related medicinal products.

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

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

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    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.

  3. Stability indicating RP-HPLC method for simultaneous determination of piroxicam and ofloxacin in binary combination.

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    John, Peter; Azeem, Waqar; Ashfaq, Muhammad; Khan, Islam Ullah; Razzaq, Syed Naeem

    2015-09-01

    A simple and precise RP-HPLC method was developed for simultaneous determination of piroxicam and ofloxacin in pharmaceutical formulations and human serum. Optimum separations of piroxicam, ofloxacin and stress-induced degradation products were achieved by use of Hypersil BDS C8 column (250 x 4.6mm, 5 μm). The mobile phase was a mixture of acetonitrile: 0.012M K2HPO4: 0.008M sodium citrate (both buffers mixed and pH adjusted to 2.8) (50:25:25 v/v/v) delivered at flow rate of 1.5 mL min⁻¹ using DAD at 254 nm. Response was linear function of concentration over the ranges of 70-130 mg mL⁻¹ for piroxicam and ofloxacin (r² ≥ 0.999). The method efficiently separated the analytical peaks from degradation products with acceptable tailing and resolution. The developed method was successfully used for concurrent analysis of piroxicam and ofloxacin in pharmaceutical formulations, human serum and in vitro drug interaction studies.

  4. Comparison of two ultrasound-enhanced microextractions combined with HPLC for determining acaricides in water.

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    Peng, Bing; Yang, Xiaoling; Zhang, Jiaheng; Du, Fengpei; Zhou, Wenfeng; Gao, Haixiang; Lu, Runhua

    2013-07-01

    An ultrasound-enhanced in situ solvent formation microextraction has been developed first time and compared with ultrasound-enhanced ionic-liquid-assisted dispersive liquid-liquid microextraction for the HPLC analysis of acaricides in environmental water samples. A ionic liquid ([C8MIM][PF6]) was used as the green extraction solvent through two pathways. The experimental parameters, such as the type and volume of both of the extraction solvent disperser solvent, ultrasonication time, and salt addition, were investigated and optimized. The analytical performance using the optimized conditions proved the feasibility of the developed methods for the quantitation of trace levels of acaricides by obtaining limits of detection that range from 0.54 to 3.68 μg/L. The in situ solvent formation microextraction method possesses more positive characteristics than the ionic-liquid-assisted dispersive liquid-liquid microextraction method (except for spirodiclofen determination) when comparing the validation parameters. Both methods were successfully applied to determining acaricides in real water samples.

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

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    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.

  6. Human-Agent Decision-making: Combining Theory and Practice

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    Sarit Kraus

    2016-06-01

    Full Text Available Extensive work has been conducted both in game theory and logic to model strategic interaction. An important question is whether we can use these theories to design agents for interacting with people? On the one hand, they provide a formal design specification for agent strategies. On the other hand, people do not necessarily adhere to playing in accordance with these strategies, and their behavior is affected by a multitude of social and psychological factors. In this paper we will consider the question of whether strategies implied by theories of strategic behavior can be used by automated agents that interact proficiently with people. We will focus on automated agents that we built that need to interact with people in two negotiation settings: bargaining and deliberation. For bargaining we will study game-theory based equilibrium agents and for argumentation we will discuss logic-based argumentation theory. We will also consider security games and persuasion games and will discuss the benefits of using equilibrium based agents.

  7. HPLC/FLD测定聚酯纤维纺织品中9种非离子荧光增白剂%Determination of nine non-ionic fluorescent whitening agent residues in polyester fibre textile by HPLC/FLD

    Institute of Scientific and Technical Information of China (English)

    吴晓琼; 丁友超; 汤娟; 徐海; 郑丹丹

    2016-01-01

    建立了纺织品中DT、SWN、OB、KSN、ER-Ⅰ、ER-Ⅱ、KCB、OB-Ⅰ、OB-Ⅱ9种非离子荧光增白剂(FWAs)的前处理方法以及高效色谱荧光检测(HPLC/FLD)方法。样品经二甲苯提取、浓缩、定容后,进行HPLC/FLD定性定量分析。采用Phenomenex Gemini 5u C18(150 mm×4.6 mm,5μm)色谱柱进行分离,以乙腈-2.5 mmol/L乙酸铵溶液为流动相,梯度洗脱。9种非离子FWAs的相关系数均不小于0.9993,定量下限(LOQs,S/N=10)为0.70~0.95 mg/kg。不同添加水平下,9种非离子FWAs的回收率为83.0%~100%,相对标准偏差(RSDs)为4.0%~8.8%。该方法简单、灵敏度高,具有一定的实际应用价值。%A sample pertreatment coupled to high performance with fluorescent detector (HPLC/FLD) method was developed for determination of nine non-ionic fluorescent whitening agents, including 1,2-bis(5-methyl-2-benzoxazole)ethylene (DT), 7-diethylamino-4-methylcoumarin (SWN), 2,2′-(2,5-thiophenedi⁃yl)bis[5-(1,1-dimethylethyl)-benzoxazol] (OB), 2-[4-[2-[4-(2-benzoxazolyl)phenyl]ethenyl]phenyl]-5-methyl-benzoxazol (KSN), 1,4-bis(2-cyano styryl)benzene (ER-Ⅰ), 1-(2-cyano styryl)-4-1-(2-cyano styryl)-4-(4-cy⁃ano styryl) benzene (ER-Ⅱ), 2,2′-(1,4-naphthalenediyl)bis-benzoxazol (KCB), 4,4′-bis[2-(2-methoxyphenyl) ethenyl]-1′-biphenyl (OB-Ⅰ), 2,2′-(1,2-ethenediyldi-4,1-phenylene)bis(5-methyl-benzoxazol) (OB-Ⅱ) in textile. The sample was extracted with xylene and concentrated, and then qualitatively and quantitatively ana⁃lyzed by HPLC/FLD. The separation of target compounds was performed on a phenomenex Gemini 5u C18 (150 mm × 4.6 mm,5 μm) column by gradient elution using acetonitrile/ammonium acetate solution (containing 2.5 mmol/L ammonium acetate) as mobile phase. The correlation coefficients of nine kinds of non-ionic fluo⁃rescent whitening agents was not less than 0.999 3. The limits of quantification of the nine compounds (LOQs, S/N=10) were 0

  8. 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)

  9. 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.

  10. 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.

  11. 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.

  12. Retention modeling in combined pH/organic solvent gradient reversed-phase HPLC.

    Science.gov (United States)

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

    2013-07-07

    An approach for retention modeling of double pH/organic solvent gradient data easily generated by automatically mixing two mobile phases with different pH and organic content according to a linear pump program is proposed. This approach is based on retention models arising from the evaluation of the retention data of a set of 17 OPA derivatives of amino acids obtained in 27 combined pH/organic solvent gradient runs performed between fixed initial pH/organic modifier values but different final ones and for different gradient duration. The derived general model is a ninth parameter equation easily manageable through a linear least-squares fitting but it requires eighteen initial pH/organic modifier gradient experiments for a satisfactory retention prediction in various double gradients of the same kind with those used in the fitting procedure. Two simplified versions of the general model, which were parameterized based on six only initial pH/organic modifier gradients, were also proposed, when one of the final double gradient conditions, pH or organic content was kept constant. The full and the simplified models allowed us to predict the experimental retention data in simultaneous pH/organic solvent double gradient mode very satisfactorily without the solution of the fundamental equation of gradient elution.

  13. Simultaneous Estimation of Gemcitabine Hydrochloride and Capecitabine Hydrochloride in Combined Tablet Dosage Form by RP-HPLC Method

    Directory of Open Access Journals (Sweden)

    V. Rajesh

    2011-01-01

    Full Text Available A new reverse phase high performance liquid chromatography (RP-HPLC method has been developed for the simultaneous estimation of gemcitabine hydrochloride and capecitabine hydrochloride in combined tablet dosage form. An inertsil ODS-3 C-18 column having dimensions of 250×4.6 mm and particle size of 5 µm, with mobile phase containing a mixture of acetonitrile : water : triethyelamine in the ratio of (70 : 28 : 2v/v was used. The pH of mobile phase was adjusted to 4.0 with ortho-phosphoric acid. The flow rate was 1 mL/min and the column effluents were monitored at 260 nm. The retention time for gemcitabine hydrochloride and capecitabine hydrochloride was found to be 2.76 and 2.3 min respectively. The proposed method was validated in terms of linearity, accuracy, precision, limit of detection, limit of quantitation and robustness. The method was found to be linear in the range of 10-50 µg/mL and 4-24 µg/mL for gemcitabine hydrochloride and capecitabine hydrochloride, with regression coefficient r = 0.999 and r = 0.999, respectively.

  14. Simultaneous determination of dorzolomide and timolol in aqueous humor: a novel salting out liquid-liquid microextraction combined with HPLC.

    Science.gov (United States)

    Mohamed, Abdel-Maaboud Ismail; Abdel-Wadood, Hanaa Mohammed; Mousa, Heba Salah

    2014-12-01

    A Snovel method for the simultaneous separation and determination of two antiglaucoma drugs namely, dorzolamide hydrochloride (DOR) and timolol maleate (TIM) in aqueous humor samples (AH) was developed by using salting-out assisted liquid-liquid microextraction (SALLME) combined with HPLC-UV method. Box-Behnken experimental design and response surface methodology were employed to assist the optimization of SALLME conditions, including salt concentration, the pH of sample solution and vortex time as variable factors. The optimal extraction conditions were as follows: to 50 µL of AH sample, 100 µL of phosphate buffer (100 mmol L(-1), pH 11.9), 90 µL of acetonitrile (ACN) and 0.11 g of (NH4)2SO4 salt were added into an Eppendorf vial (1 mL) then vortexed for 1.1 min. As an effort to miniaturize SALLE system, a 1 mL syringe adapted with a capillary tube was employed as the phase separation device. Once the phase separation occurred, the upper layer could be narrowed into the capillary tube by pushing the plunger; thus, the collection of the upper layer solvent was simple and convenient. By miniaturization, the consumption of the organic solvent was decreased as low as possible. The chromatographic separation was achieved on Gemini C18 column using a mobile phase of ACN: 30 mmol L(-1) potassium dihydrogen phosphate buffer containing 0.1% triethylamine, pH 3.5 (20:80, v/v) at a flow rate of 1 mL min(-1) and UV detection at 254 and 295 nm for DOR and TIM, respectively. Mepivacaine hydrochloride was used as an internal standard. The described method showed better separation with enhanced sensitivities than the previously reported methods with limits of quantitation of 8.75 and 10.32 ng mL(-1) in aqueous solution and 15.97 and 23.53 ng mL(-1) in AH for DOR and TIM, respectively. The simple, rapid and eco-friendly SALLME-HPLC method has been successfully applied for the simultaneous pharmacokinetic studies of DOR and TIM in rabbit AH.

  15. Combination of HPLC chromatogram and hypoglycemic effect identifies isoflavones as the principal active fraction of Belamcanda chinensis leaf extract in diabetes treatment.

    Science.gov (United States)

    Chen, Yan; Wu, Chong-Ming; Dai, Rong-Ji; Li, Liang; Yu, Yu-Hong; Li, Yan; Meng, Wei-Wei; Zhang, Liang; Zhang, Yongqian; Deng, Yu-Lin

    2011-02-15

    In previous study, we demonstrated the hypoglycemic effect of aqueous extract of Belamcanda chinensis leaves in rats. Here, we separated the aqueous extract of B. chinensis leaves and investigated the spectrum-effect relationships between HPLC chromatograms and hypoglycemic activities of different isolates from B. chinensis leaf extract. Sequential solvent extraction with petroleum ether, chloroform, acetic ester and n-butanol provided several isolates showing similar hypoglycemic activities, making it difficult to discriminate the active fractions. Stepwise elution through HP20 macroporous resin by water, 40% and 95% ethanol provided isolates with distinct hypoglycemic activities, representing a simple, rapid and efficient preparative separation method. Combination of HPLC chromatogram and pharmacological effect targeted a hypoglycemic activity-related region in HPLC chromatogram. Each peak in this region was analyzed by UV spectrum scan. Most of them were flavonoids in which tectoridin and swertisin were known flavonoids with anti-diabetic activities. In together, this work provides a general model of combination of HPLC chromatography and pharmacological effect to study the spectrum-effect relationships of aqueous extract from B. chinensis leaves, which can be used to find principle components of B. chinensis on pharmacological activity.

  16. Application of HPLC Combined with Laser Induced Fluorescence for Protein Profile Analysis of Tissue Homogenates in Cervical Cancer

    OpenAIRE

    Sujatha Bhat; Ajeetkumar Patil; Lavanya Rai; Kartha, V. B.; Santhosh Chidangil

    2012-01-01

    A highly objective method, High Performance Liquid Chromatography with Laser Induced Fluorescence (HPLC-LIF) technique was used to study the protein profiles of normal and cervical cancer tissue homogenates. A total of 44 samples including normal cervical biopsy samples from the hysterectomy patients and the patients suffering from different stages of the cervical cancer were recorded by HPLC-LIF and analysed by Principle Component Analysis (PCA) to get statistical information on different t...

  17. Use of biologic agents in combination with other therapies for the treatment of psoriasis.

    Science.gov (United States)

    Cather, Jennifer C; Crowley, Jeffrey J

    2014-12-01

    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)-α and interleukins (ILs)-12/23. While biologic agents have improved treatment outcomes, they are not effective in all individuals with psoriasis. The combination of biologic agents with traditional therapies may provide improved therapeutic options for patients who inadequately respond to a single drug or when efficacy may be increased with supplementation of another treatment. In addition, combination therapy may reduce safety concerns and cumulative toxicity, as lower doses of individual agents may be efficacious when used together. This article reviews the current evidence available on the efficacy and safety of combining biologic agents with systemic therapies (methotrexate, cyclosporine, or retinoids) or with phototherapy, and the combination of biologic agents themselves. Guidance is provided to help physicians identify situations and the characteristics of patients who would benefit from combination therapy with a biologic agent. Finally, the potential clinical impact of biologic therapies in development (e.g., those targeting IL-17A, IL-17RA, or IL-23 alone) is analyzed.

  18. Determination of Diclofenac Potassium Dry Suspension Agent by HPLC%HPLC测双氯芬酸钾干混悬剂的含量

    Institute of Scientific and Technical Information of China (English)

    隋丽丽; 孟祥军

    2015-01-01

    The high performance liquid chromatography ( HPLC) method for the content of diclofenac potassium dry suspension agent was established to study the high performance liquid chromatography ( HPLC) method for the content of diclofenac potassium dry suspension agent, using chromatographic column for Kromasil C18 ( 250 mm × 4. 6 mm, 2. 5 μm), mobile phase methanol-water-acetic acid glacial (80:20:0. 8), detection wavelength of 276 nm, flow rate of 1. 0 mL·min-1, sample amount to 20 μL. Results showed that 40999x+y=40999 (r=0. 9995, n=7) with linear range of 4. 0~6. 0 μg·mL-1, the minimum detection limit was 1. 66 ng, quantitative limit was 5. 56 ng. The average recovery was 99. 57%. The method is suitable for determination of the diclofenac potassium dry suspension agent, and it is convenient, accurate, simple and feasible.%建立了高效液相色谱法测定双氯芬酸钾干混悬剂含量的测定方法。色谱柱为 Kromasil C18(250 mm ×4.6 mm,2.5μm),流动相:甲醇-水-冰醋酸(80:20:0.8, V:V:V),检测波长为276 nm,流速为1.0 mL·min-1,进样量为20μL。结果表明: y=40999x+119667(r=0.9995, n=7)线性范围为4.0~6.0μg·mL-1;最低检测限为1.66 ng,定量限为5.56 ng;平均回收率为99.57%。该方法简便、准确、适用于双氯芬酸钾干混悬剂的含量测定。

  19. 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...

  20. 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.

  1. Validated Stability Indicating RP-HPLC Method for Simultaneous Estimation of Codeine Phosphate and Chlorpheniramine Maleate from Their Combined Liquid Dosage Form

    Directory of Open Access Journals (Sweden)

    Ramakrishna Kommana

    2013-01-01

    Full Text Available The present paper describes the development of quick stability indicating RP-HPLC method for the simultaneous estimation of codeine phosphate and chlorpheniramine maleate in the presence of its degradation products, generated from forced degradation studies. The developed method separates codeine phosphate and chlorpheniramine maleate in impurities/degradation products. Codeine phosphate and chlorpheniramine maleate and their combination drug product were exposed to acid, base, oxidation, dry heat, and photolytic stress conditions, and the stressed samples were analysed by proposed method. The proposed HPLC method utilizes the Shimadzu HPLC system on a Phenomenex C18 column (, 5 μ using a mixture of 1% o-phosphoric acid in water : acetonitrile : methanol (78 : 10 : 12 mobile phase with pH adjusted to 3.0 in an isocratic elution mode at a flow rate of 1 mL/min, at 23°C with a load of 20 μL. The detection was carried out at 254 nm. The retention time of codeine phosphate and chlorpheniramine maleate was found to be around 3.47 min and 9.45 min, respectively. The method has been validated with respect to linearity, robustness, precision, accuracy, limit of detection (LOD, and limit of quantification (LOQ. The developed validated stability indicating HPLC method was found to be simple, accurate, and reproducible for the determination of instability of these drugs in bulk and commercial products.

  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. Chemometrics-Assisted UV Spectrophotometric and RP-HPLC Methods for the Simultaneous Determination of Tolperisone Hydrochloride and Diclofenac Sodium in their Combined Pharmaceutical Formulation.

    Science.gov (United States)

    Gohel, Nikunj Rameshbhai; Patel, Bhavin Kiritbhai; Parmar, Vijaykumar Kunvarji

    2013-01-01

    Chemometrics-assisted UV spectrophotometric and RP-HPLC methods are presented for the simultaneous determination of tolperisone hydrochloride (TOL) and diclofenac sodium (DIC) from their combined pharmaceutical dosage form. Chemometric methods are based on principal component regression and partial least-square regression models. Two sets of standard mixtures, calibration sets, and validation sets were prepared. Both models were optimized to quantify each drug in the mixture using the information included in the UV absorption spectra of the appropriate solution in the range 241-290 nm with the intervals λ = 1 nm at 50 wavelengths. The optimized models were successfully applied to the simultaneous determination of these drugs in synthetic mixture and pharmaceutical formulation. In addition, an HPLC method was developed using a reversed-phase C18 column at ambient temperature with a mobile phase consisting of methanol:acetonitrile:water (60:30:10 v/v/v), pH-adjusted to 3.0, with UV detection at 275 nm. The methods were validated in terms of linearity, accuracy, precision, sensitivity, specificity, and robustness in the range of 3-30 μg/mL for TOL and 1-10 μg/mL for DIC. The robustness of the HPLC method was tested using an experimental design approach. The developed HPLC method, and the PCR and PLS models were used to determine the amount of TOL and DIC in tablets. The data obtained from the PCR and PLS models were not significantly different from those obtained from the HPLC method at 95% confidence limit.

  4. Use of combination of leflunomide with biological agents in treatment of rheumatoid arthritis.

    NARCIS (Netherlands)

    Kalden, J.R.; Antoni, C.; Alvaro-Gracia, J.M.; Combe, B.; Emery, P.; Kremer, J.M.J.; Strand, C.V.; Riel, P.L.C.M. van; Smolen, J.S.

    2005-01-01

    An Expert Panel Meeting was held in May 2004 to assess experience with combination therapy with leflunomide and biological agents in the treatment of rheumatoid arthritis (RA), to identify both optimal use of such combinations and precautions for use. Eleven published prospective or retrospective st

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

    Science.gov (United States)

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

    2015-10-01

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

  6. HPLC-MS-MS Method Development and Validation of Antileishmanial Agent, S010-0269, in Hamster Serum.

    Science.gov (United States)

    Sharma, Abhisheak; Jaiswal, Swati; Shukla, Mahendra; Sharma, Moni; Chauhan, Prem Man Singh; Rangaraj, Nagarjun; Vaghasiya, Kalpesh; Lal, Jawahar

    2015-10-01

    A rapid, sensitive and simple high-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of the antileishmanial agent, S010-0269, in hamster serum. A Discovery HS C-18 column (5 μm, 50 × 4.6 mm) maintained at 40°C was utilized for chromatographic separation with mobile phase [acetonitrile: aqueous ammonium acetate (0.01 M) buffer (85:15, v/v)] at a flow rate of 0.6 mL/min. The method requires low serum volume (20 µL) with a run time of 3.5 min. Excellent linear relationships (r ≥ 0.99) were obtained between the measured and added concentration over a range of 1-200 ng/mL. Validation parameters (accuracy, specificity, precision, recovery, matrix effect and stability) were assessed as per FDA guidelines. The precision and accuracy were acceptable as indicated by relative standard deviation ranging from 2.3 to 13.6% and bias values ranging from 1.5 to 6.5%, respectively. Moreover, the compound was found stable in hamster serum even after 30 days of storage at -80°C and being subjected to two freeze-thaw cycles. The validated method was successfully applied to the pharmacokinetic study after 10 mg/kg oral dose of S010-0269 in hamsters.

  7. 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).

  8. Determination of the Component of Fluorescent Whitening Agent CBS-127 by HPLC%HPLC法测定荧光增白剂CBS-127的含量

    Institute of Scientific and Technical Information of China (English)

    李自红; 魏悦; 范毅; 董建军

    2013-01-01

    The method for determinating the content of Fluorescent Whitening Agent CBS-127 by HPLC was established.Sunfire C18 column (4.6 mm×150 mm,5 μm) was used with methanol-water (90%:10%) as the mobile phase.The flow rate of the mobile phase was 1.0 mL/min.The detection wavelength was 356 nm.The column temperature was 40 C.There was good linear relationship in the range of 0.5~2.5 μg (r=0.999 9).The recovery rate was 99.78% and RSD value is 0.7% (n=6).This method is high accuracy,good reproducibility,reliable results,which is an effective method for the Fluorescent Whitening Agent CBS-127.%建立了高效液相色谱法测定荧光增白剂CBS-127含量的方法.采用Sunfire C18 (4.6 mm×150 mm,5μm)色谱柱,流动相为甲醇-水(90%:10%),流速为1.0 mL/min,紫外检测波长为356 nm,柱温40℃.CBS-127在0.5~2.5 μg范围内有良好线性关系(r=0.999 9);加样回收率为99.78%,RSD值为0.7%(n=6).该方法精密度高、重现性好、结果准确可靠,为荧光增白剂CBS-127的质量评价提供了有效的方法.

  9. 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.

  10. 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.

  11. Optimization of high pressure machine decocting process for Dachengqi Tang using HPLC fingerprints combined with the Box–Behnken experimental design

    Directory of Open Access Journals (Sweden)

    Rui-Fang Xie

    2015-04-01

    Full Text Available Using Dachengqi Tang (DCQT as a model, high performance liquid chromatography (HPLC fingerprints were applied to optimize machine extracting process with the Box–Behnken experimental design. HPLC fingerprints were carried out to investigate the chemical ingredients of DCQT; synthetic weighing method based on analytic hierarchy process (AHP and criteria importance through intercriteria correlation (CRITIC was performed to calculate synthetic scores of fingerprints; using the mark ingredients contents and synthetic scores as indicators, the Box–Behnken design was carried out to optimize the process parameters of machine decocting process under high pressure for DCQT. Results of optimal process showed that the herb materials were soaked for 45 min and extracted with 9 folds volume of water in the decocting machine under the temperature of 140 °C till the pressure arrived at 0.25 MPa; then hot decoction was excreted to soak Dahuang and Mangxiao for 5 min. Finally, obtained solutions were mixed, filtrated and packed. It concluded that HPLC fingerprints combined with the Box–Behnken experimental design could be used to optimize extracting process of traditional Chinese medicine (TCM.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ataman, Ozlem U., E-mail: ouataman@hotmail.com [Global Medicines Development, AstraZeneca, Alderley Park, Macclesfield, Cheshire (United Kingdom); Sambrook, Sally J. [Global Medicines Development, AstraZeneca, Alderley Park, Macclesfield, Cheshire (United Kingdom); Wilks, Chris [Innovative Medicines, AstraZeneca, Alderley Park, Macclesfield, Cheshire (United Kingdom); Lloyd, Andrew [Global Medicines Development, AstraZeneca, Alderley Park, Macclesfield, Cheshire (United Kingdom); Taylor, Amanda E. [Yellow Delaney Communications Ltd, Wilmslow, Cheshire (United Kingdom); Wedge, Stephen R. [Innovative Medicines, AstraZeneca, Alderley Park, Macclesfield, Cheshire (United Kingdom)

    2012-11-15

    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

  13. 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

  14. 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.

  15. 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.

  16. Combined blood pool and extracellular contrast agents for pediatric and young adult cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Joyce T. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Robinson, Joshua D. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Deng, Jie [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Rigsby, Cynthia K. [Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States)

    2016-12-15

    A comprehensive cardiac magnetic resonance (cardiac MR) study including both late gadolinium enhancement (LGE) and MR angiography may be indicated for patients with a history of acquired or congenital heart disease. To study the novel use of an extracellular agent for assessment of LGE combined with a blood pool contrast agent for detailed MR angiography evaluation to yield a comprehensive cardiac MR study in these patients. We reviewed clinical cardiac MR studies utilizing extracellular and blood pool contrast agents and noted demographics, clinical data and adverse events. We rated LGE image quality and MR angiography image quality for each vascular segment and calculated inter-rater variability. We also quantified contrast-to-noise ratio (CNR). Thirty-three patients (mean age 13.9 ± 3 years) received an extracellular contrast agent (10 gadobenate dimeglumine, 23 gadopentetate dimeglumine) and blood pool contrast agent (33 gadofosveset trisodium). No adverse events were reported. MRI indications included Kawasaki disease (8), cardiomyopathy and coronary anatomy (15), repaired congenital heart disease (8), and other (2). Mean LGE quality was 2.6 ± 0.6 with 97% diagnostic imaging. LGE quality did not vary by type of contrast agent given (P = 0.07). Mean MR angiography quality score was 4.7 ± 0.6, with high inter-rater agreement (k = 0.6-0.8, P < 0.002). MR angiography quality did not vary by type of contrast agent used (P = 0.6). Cardiac MR studies utilizing both extracellular and blood pool contrast agents are feasible and safe and provide excellent-quality LGE and MR angiography images. The use of two contrast agents allows for a comprehensive assessment of both myocardial viability and vascular anatomy during the same exam. (orig.)

  17. Assessment of powder blend uniformity: Comparison of real-time NIR blend monitoring with stratified sampling in combination with HPLC and at-line NIR Chemical Imaging.

    Science.gov (United States)

    Bakri, Barbara; Weimer, Marco; Hauck, Gerrit; Reich, Gabriele

    2015-11-01

    Scope of the study was (1) to develop a lean quantitative calibration for real-time near-infrared (NIR) blend monitoring, which meets the requirements in early development of pharmaceutical products and (2) to compare the prediction performance of this approach with the results obtained from stratified sampling using a sample thief in combination with off-line high pressure liquid chromatography (HPLC) and at-line near-infrared chemical imaging (NIRCI). Tablets were manufactured from powder blends and analyzed with NIRCI and HPLC to verify the real-time results. The model formulation contained 25% w/w naproxen as a cohesive active pharmaceutical ingredient (API), microcrystalline cellulose and croscarmellose sodium as cohesive excipients and free-flowing mannitol. Five in-line NIR calibration approaches, all using the spectra from the end of the blending process as reference for PLS modeling, were compared in terms of selectivity, precision, prediction accuracy and robustness. High selectivity could be achieved with a "reduced" approach i.e. API and time saving approach (35% reduction of API amount) based on six concentration levels of the API with three levels realized by three independent powder blends and the additional levels obtained by simply increasing the API concentration in these blends. Accuracy and robustness were further improved by combining this calibration set with a second independent data set comprising different excipient concentrations and reflecting different environmental conditions. The combined calibration model was used to monitor the blending process of independent batches. For this model formulation the target concentration of the API could be achieved within 3 min indicating a short blending time. The in-line NIR approach was verified by stratified sampling HPLC and NIRCI results. All three methods revealed comparable results regarding blend end point determination. Differences in both mean API concentration and RSD values could be

  18. Validated Stability-Indicating HPLC-DAD Method for the Simultaneous Determination of Diclofenac Sodium and Diflunisal in Their Combined Dosage Form.

    Science.gov (United States)

    Shaalan, Rasha A; Belal, Tarek S

    2013-01-01

    A simple, rapid, and highly selective HPLC-DAD method was developed for the simultaneous determination of diclofenac sodium (DIC) and diflunisal (DIF) in pure form and in their combined formulation. Effective chromatographic separation was achieved using a Zorbax SB-C8 (4.6×250 mm, 5 μm particle size) column with a mobile phase composed of 0.05 M phosphoric acid, acetonitrile, and methanol in the ratio of 40:48:12 (by volume). The mobile phase was pumped isocratically at a flow rate of 1 mL/min, and quantification of the analytes was based on measuring their peak areas at 228 nm. The retention times for diflunisal and diclofenac were about 7.9 and 9.5 min, respectively. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to system suitability, linearity, ranges, precision, accuracy, specificity, robustness, detection, and quantification limits. Calibration curves were linear in the ranges of 5-100 μg/mL for both drugs with correlation coefficients >0.9998. The proposed method proved to be selective and stability-indicating by the resolution of the two analytes from four of their related substances and potential impurities as well as from forced-degradation (hydrolysis, oxidation, photolysis, and dry heat) products. The validated HPLC method was successfully applied to the analysis of DIC and DIF in their combined dosage form (suppositories). The proposed method made use of the diode array detector (DAD) as a tool for peak identity and purity confirmation.

  19. The In Vitro Antimicrobial Effects of Lavandula angustifolia Essential Oil in Combination with Conventional Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Stephanie de Rapper

    2016-01-01

    Full Text Available The paper focuses on the in vitro antimicrobial activity of Lavandula angustifolia Mill. (lavender essential oil in combination with four commercial antimicrobial agents. Stock solutions of chloramphenicol, ciprofloxacin, nystatin, and fusidic acid were tested in combination with L. angustifolia essential oil. The antimicrobial activities of the combinations were investigated against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538 and Gram-negative Pseudomonas aeruginosa (ATCC 27858 and Candida albicans (ATCC 10231 was selected to represent the yeasts. The antimicrobial effect was performed using the minimum inhibitory concentration (MIC microdilution assay. Isobolograms were constructed for varying ratios. The most prominent interaction was noted when L. angustifolia essential oil was combined with chloramphenicol and tested against the pathogen P. aeruginosa (ΣFIC of 0.29. Lavendula angustifolia essential oil was shown in most cases to interact synergistically with conventional antimicrobials when combined in ratios where higher volumes of L. angustifolia essential oil were incorporated into the combination.

  20. Application of HPLC combined with laser induced fluorescence for protein profile analysis of tissue homogenates in cervical cancer.

    Science.gov (United States)

    Bhat, Sujatha; Patil, Ajeetkumar; Rai, Lavanya; Kartha, V B; Chidangil, Santhosh

    2012-01-01

    A highly objective method, High Performance Liquid Chromatography with Laser Induced Fluorescence (HPLC-LIF) technique was used to study the protein profiles of normal and cervical cancer tissue homogenates. A total of 44 samples including normal cervical biopsy samples from the hysterectomy patients and the patients suffering from different stages of the cervical cancer were recorded by HPLC-LIF and analysed by Principle Component Analysis (PCA) to get statistical information on different tissue components. Discrimination of different stages of the samples was carried out by considering three parameters--scores of factor, spectral residual, and Mahalanobis Distance. Diagnostic accuracy of the method was evaluated using Receiver Operating Characteristic (ROC) analysis, and Youden's index (J) plots. The PCA results showed high sensitivity and specificity (~100) for cervical cancer diagnosis. ROC and Youden's index curves for both normal and malignant standard sets show good diagnostic accuracy with high AUC values. The statistical analysis has shown that the differences in protein profiles can be used to diagnose biochemical changes in the tissue, and thus can be readily applied for the detection of cervical cancer, even in situations where a histopathology examination is not easy because of nonavailability of experienced pathologists.

  1. Application of HPLC Combined with Laser Induced Fluorescence for Protein Profile Analysis of Tissue Homogenates in Cervical Cancer

    Directory of Open Access Journals (Sweden)

    Sujatha Bhat

    2012-01-01

    Full Text Available A highly objective method, High Performance Liquid Chromatography with Laser Induced Fluorescence (HPLC-LIF technique was used to study the protein profiles of normal and cervical cancer tissue homogenates. A total of 44 samples including normal cervical biopsy samples from the hysterectomy patients and the patients suffering from different stages of the cervical cancer were recorded by HPLC-LIF and analysed by Principle Component Analysis (PCA to get statistical information on different tissue components. Discrimination of different stages of the samples was carried out by considering three parameters—scores of factor, spectral residual, and Mahalanobis Distance. Diagnostic accuracy of the method was evaluated using Receiver Operating Characteristic (ROC analysis, and Youden's index (J plots. The PCA results showed high sensitivity and specificity (∼100 for cervical cancer diagnosis. ROC and Youden's index curves for both normal and malignant standard sets show good diagnostic accuracy with high AUC values. The statistical analysis has shown that the differences in protein profiles can be used to diagnose biochemical changes in the tissue, and thus can be readily applied for the detection of cervical cancer, even in situations where a histopathology examination is not easy because of nonavailability of experienced pathologists.

  2. Analytical Method Development and Validation of Esomeprazole and Levosulpiride in their Combined Capsule Dosage Form by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Patel H

    2012-07-01

    Full Text Available A new simple, accurate, rapid and precise isocratic Reverse Phase High performance liquid chromatographic (HPLC method was developed and validated for the determination of Esomeprazole (ESO, and Levosulpiride (LEVO in capsule formulation. The Method employs Shimadzu HPLC system on Hypercil BDS C18 (25 cm × 4.6 mm i.e., 5 µm and flow rate of 1 ml/min with a load of 20µl. Acetonitrile and Phosphate buffer was used as mobile phase in the composition of 50:50 at 3.5 PH. The Detection was carried out at 240 nm. Linearity ranges for Esomeprazole and Levosulpiride were 20-60 µg/ml, 37.5-225 µg/ml respectively. Retention Time of Levosulpiride and Esomeprazole were found to be 3.367 min, 4.320 min respectively. Percent Recovery study values of Esomeprazole and Levosulpiride were found to be within 98-102%. This newly developed method was successfully utilized for the Quantitative estimation of Esomeprazole and Levosulpiride in pharmaceutical dosage forms. This method was validated for accuracy, precision, linearity and Robustness as per ICH guidelines.

  3. In vitro activities of antimicrobial agents, alone and in combination, against Acinetobacter baumannii isolated from blood.

    Science.gov (United States)

    Chang, S C; Chen, Y C; Luh, K T; Hsieh, W C

    1995-11-01

    In vitro activities of 15 antimicrobial agents against 90 strains of Acinetobacter baumannii isolated from blood cultures from hospitalized patients were determined using the agar dilution method. Imipenem, ofloxacin, and ciprofloxacin had the best antimicrobial activity with minimum inhibitory concentrations (MIC50s) of 0.25 mu g/ml and MIC90s of 0.5-1 mu g/ml. beta-lactam antibiotics other than imipenem had poor activity, with MIC50s ranging from 8 to 64 mu g/ml and MIC90s from 32 to > or = 256 mu g/ml. The checkerboard titration method was used to study the effects of combination of two antimicrobial agents. Combinations of ceftazidime, aztreonam, imipenem, or ciprofloxacin with amikacin showed either synergistic effects or partial synergistic effects for 40.9%-86.4% of 22 tested strains. The best in vitro activity was observed with the combination of imipenem and amikacin. No antagonistic effects were observed with the combination of imipenem and amikacin. Synergistic effects were confirmed by time-kill curve studies. In conclusion, imipenem, ofloxacin, and ciprofloxacin were the three most active agents against human blood isolates of A. baumannii. The combination of a beta-lactam or ciprofloxacin with amikacin was synergistic for some of the isolates.

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

    OpenAIRE

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

    2016-01-01

    Objective The objective of this study was to evaluate the antitumor effects of lurbinectedin as a single agent or in combination with existing anticancer agents for clear cell carcinoma (CCC) of the ovary, which is regarded as an aggressive, chemoresistant, histological subtype. Methods Using human ovarian CCC cell lines, the antitumor effects of lurbinectedin, SN-38, doxorubicin, cisplatin, and paclitaxel as single agents were assessed using the MTS assay. Then, the antitumor effects of comb...

  5. 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。

  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.

  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. 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.

  10. 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) C18 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

  11. Analysis of in vitro chemoprevention of genotoxic damage by phytochemicals, as single agents or as combinations.

    Science.gov (United States)

    Abraham, Suresh K; Eckhardt, Alexander; Oli, Rajaraman G; Stopper, Helga

    2012-05-15

    Cancer chemoprevention with low-dose combinations of bioactive phytochemicals instead of single agents has been suggested to induce less toxicity and improve efficacy. In this study, we selected four plant food-based phytochemicals, viz. chlorogenic acid (CLA), pelargonidin (PEL), resveratrol (RES) and epigallocatechin gallate (EGCG) to evaluate the in vitro chemoprevention of genotoxic damage in HL-60 cells. These agents were tested either individually or as a combination at two concentrations (with a 10-fold difference) against the genotoxins mitomycin C (MMC), diepoxybutane (DEB) and patulin (PAT). Our preliminary ferric reducing antioxidant power (FRAP) assay demonstrated additive effects when PEL, CLA, RES and EGCG were combined. Results of the cytokinesis-block micronucleus test showed significant protection against genotoxic damage induced by PAT, DEB and MMC when CLA, PEL, RES and EGCG were tested individually. This protective effect of the phytochemicals was not concentration-related. Both low- and high-concentration combinations of CLA, PEL, RES and EGCG showed significant reducing effects on the frequencies of micronuclei induced by PAT, DEB and MMC. However, the micronucleus test did not provide indications of additive or synergistic effects with this combination of phytochemicals. In conclusion, the chemo-preventive effects of PEL, CLA, RES and EGCG against genotoxic damage induced by MMC, DEB and PAT are indicative of a 'saturation effect' when higher concentrations and combinations of these phytochemicals are used.

  12. 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.

  13. 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...

  14. Synergistic combinations of antifungals and anti-virulence agents to fight against Candida albicans

    OpenAIRE

    Cui, Jinhui; Ren, Biao; Tong, Yaojun; Dai, Huanqin; Zhang, Lixin

    2015-01-01

    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-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 d...

  15. 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.

  16. 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.

  17. 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.

  18. Salting-out assisted liquid-liquid extraction combined with capillary HPLC for the determination of sulfonylurea herbicides in environmental water and banana juice samples.

    Science.gov (United States)

    Gure, Abera; Lara, Francisco J; Moreno-González, David; Megersa, Negussie; del Olmo-Iruela, Monsalud; García-Campaña, Ana M

    2014-09-01

    A salting-out assisted liquid-liquid extraction (SALLE) combined with capillary high performance liquid chromatography with diode array detector (capillary HPLC-DAD) was proposed for extraction and determination of residues of nine sulfonylurea herbicides (SUHs) in environmental water and banana juice samples. Various parameters affecting the extraction process such as the type and volume of the organic solvent, sample volume, type and amount of salt, pH of the sample and vortex time were optimized. Under optimum conditions, matrix matched calibration curves were established using river water and banana juice samples. Good linear relationships as well as low limits of detection, LODs (0.4-1.3 and 3-13 µg/L) and quantification, LOQs (1.3-4.3 and 10-43 µg/L) were obtained in water and banana juice samples, respectively. The precision (intra- and inter-day) of the peak areas expressed as relative standard deviations (%, RSD), at two concentration levels were below 10 % in both matrices. Recoveries obtained from spiked environmental waters (river water and groundwater) and banana juice samples, at two concentration levels, ranged from 72 to 115%. The results of the analysis revealed that the proposed SALLE-capillary HPLC method is simple, rapid, cheap and environmentally friendly, being successfully applicable for the determination of SUH residues in waters and banana juices.

  19. Multidrug Delivery Systems Based on Human Serum Albumin for Combination Therapy with Three Anticancer Agents.

    Science.gov (United States)

    Qi, Jinxu; Zhang, Yao; Gou, Yi; Lee, Philbert; Wang, Jun; Chen, Shifang; Zhou, Zuping; Wu, Xiaoyang; Yang, Feng; Liang, Hong

    2016-09-06

    When administering several anticancer drugs within a single carrier, it is important to regulate their spatial distribution so as to avoid possible mutual interference and to thus enhance the drugs' selectivity and efficiency. To achieve this, we proposed to develop human serum albumin (HSA)-based multidrug delivery systems for combination anticancer therapy. We used three anticancer agents (an organic drug [5-fluorouracil, or 5FU], a metallic agent [2-benzoylpyridine thiosemicarbazide copper II, or BpT], and a gene agent [AS1411]) to treat liver cancer and confirm our hypothesis. The structure of the HSA-palmitic acid (PA)-5FU-BpT complex revealed that 5FU and BpT, respectively, bind to the IB and IIA subdomains of HSA. Our MALDI-TOF-MS spectral data show that one AS1411 molecule is conjugated to Cys-34 of the HSA-5FU-BpT complex via a linker. Compared with unregulated three-drug combination therapy, the HSA-5FU-BpT-AS1411 complex enhances cytotoxicity in Bel-7402 cells approximately 7-fold in vitro; however, in normal cells it does not raise cytotoxicity levels. Importantly, our in vivo results demonstrate that the HSA-5FU-BpT-AS1411 complex is superior to the unregulated three-drug combination in enhancing targeting ability, inhibiting liver tumor growth, and causing fewer side effects.

  20. Antibacterial properties of the Vietnamese cajeput oil and ocimum oil in combination with antibacterial agents.

    Science.gov (United States)

    Jedlicková, Z; Mottl, O; Serý, V

    1992-01-01

    Main antibacterially active agents obtained from plants-Cajeput essential oil--1,8 cineol, linalool, alpha-terpineol and terpinen-4-ol, for example from Melalleuce leucadendron (Myrtaceae) as well as essential oil from Ocimum gratissimum (Labiatae) were combined in tests in vitro with selected antibiotics. Above mentioned plant products were found to be effective medicaments for local application in modern medical practice. Combinations with antibiotics potentiated their therapeutical action. On the basis of tests in vitro the synergistic action of these two kinds of medicaments, i.e., preparations traditionally used for a few last decades--antibiotics--might be well applied for therapeutical needs.

  1. 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...

  2. Stability-indicating RP-HPLC method for simultaneous estimation of levosalbutamol sulfate and theophylline in combined dosage form

    Directory of Open Access Journals (Sweden)

    Sagar Suman Panda

    2013-09-01

    Full Text Available A novel, simple, accurate and precise RP-HPLC method for simultaneous determination of levosalbutamol sulfate and theophylline has been developed and validated. Separation was achieved on a Phenomenex; C18 column (250 mm × 4.6 mm i.d., 5 µm using methanol: 10 mM TBAHS(tetrabutyl ammonium hydrogen sulfate (50:50, v/v as mobile phase at flow rate of 1.0 mL.min-1. The UV detection wavelength was 274 nm. The linearity is obeyed over a concentration range of 0.5-150 µg.mL-1 with correlation coefficient of 0.999 for both the drugs. The proposed method was validated by determining accuracy, precision, stability and system suitability parameters. The method was found to be robust. Specificity of the method was determined by subjecting the drugs to various stress conditions like acid, alkali, oxidation, thermal and photolytic degradation. The method was used successfully for the simultaneous determination of levosalbutamol sulfate and theophylline in syrup dosage form.

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

    Directory of Open Access Journals (Sweden)

    Rezaee Raheme

    2015-01-01

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

  4. Dosage and Dose Schedule Screening of Drug Combinations in Agent-Based Models Reveals Hidden Synergies.

    Science.gov (United States)

    Barros de Andrade E Sousa, Lisa C; Kühn, Clemens; Tyc, Katarzyna M; Klipp, Edda

    2015-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Lisa Corina Barros de Andrade e Sousa1

    2016-01-01

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

  6. 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

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

    Science.gov (United States)

    Oghabian, Zohreh; Mehrpour, Omid

    2016-01-01

    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

  8. 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.

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

    Directory of Open Access Journals (Sweden)

    Ryoko Takahashi

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

  10. 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.

  11. 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.

  12. Immobilized fusion protein affinity chromatography combined with HPLC-ESI-Q-TOF-MS/MS for rapid screening of PPARγ ligands from natural products.

    Science.gov (United States)

    Zhu, Junfeng; Yi, Xiaojiao; Liu, Wenhui; Xu, Yingchun; Chen, Shuqing; Wu, Yongjiang

    2017-04-01

    Screening agonists of peroxisome proliferator-activated receptor-γ (PPARγ) from natural products is particularly motivated by the need for effective anti-diabetic agents. However, method for direct identification of PPARγ ligands from a complex sample is rarely reported. Here we propose a novel immobilized fusion protein affinity chromatography (IFPAC) to achieve rapid multicomponent screening. First, functional human PPARγ ligand binding domain (hPPARγLBD) was bacterially produced by fusion to glutathione S-transferase (GST). The unpurified GST-hPPARγLBD was directly applied to a 96-well filter plate prepacked with glutathione sepharose. Due to the strong affinity between GST and glutathione, the fusion protein could selectively attach to the glutathione matrix with an oriented immobilization, which was rapidly purified under non-denaturing conditions. Experimental results indicated that the prepared 96-affinity column array exhibited excellent selectivity and sensitivity for fishing novel interacting compounds. The proposed approach was applied in the high-throughput screening of PPARγ ligands from natural products, followed by rapid characterization of active compounds using HPLC-ESI-Q-TOF-MS/MS. Isochlorogenic acid A in Dendranthema indicum flowers was found to be a PPARγ ligand. Our findings suggested the IFPAC could be a powerful tool for drug discovery from natural products.

  13. 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.

  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.

  15. Clinical trial success rates of anti-obesity agents: the importance of combination therapies.

    Science.gov (United States)

    Hussain, H T; Parker, J L; Sharma, A M

    2015-09-01

    The objective of this study was to construct a clinical trial profile assessing the risk of drug failure among anti-obesity agents. Research was conducted by looking at anti-obesity therapies currently on the market or in clinical trials (phases I to III) conducted from 1998 to September 2014, with the exclusion of any drugs whose phase I trial was conducted prior to January 1998. This was completed primarily through a search on http://clinicaltrials.gov where a total of 51 drugs met the search criteria. The transition probabilities were then calculated based on various classifications and compared against industry standards. The transition probability of anti-obesity agents was 8.50% whereas the transition probability of industry standards was 10.40%. Combination therapies had four times the transition probability than monotherapies, 40% and 4.75%, respectively. Therefore, it was determined that 92% of drugs fail during clinical trial testing for this indication and combination therapy appears to improve clinical trial success rates to 10-fold.

  16. 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.

  17. Treatment of cancer using pulsed electric field in combination with chemotherapeutic agents or genes.

    Science.gov (United States)

    Nishi, T; Dev, S B; Yoshizato, K; Kuratsu, J; Ushio, Y

    1997-03-01

    Electroporation is a standard laboratory technique originally developed for in vitro transfer of molecules into cells. It involves application of electrical pulses ranging from micro- to milliseconds that create transient pores in the cell membrane allowing intracellular access of exogenous molecules. This technique has been successfully applied to regress tumors in animal models by combining electroporation with chemotherapeutic agents--a process known as electrochemotherapy (ECT) which substantially enhance cytotoxicity of some antineoplastic agents. Recently ECT has moved into clinical arena and patients with cutaneous tumors and head and neck cancers have been treated very effectively with ECT. Parallel to ECT, a technique has also been developed which makes it possible to inject plasmid DNA and combine it with in vivo electroporation--electro--genetherapy (EGT)--to deliver in a highly efficient manner both marker and functional genes into target tissue and achieve gene expression. Thus, in vivo electroporation is contributing to the development of a new strategy for cancer treatment with both drugs and genes.

  18. 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.

  19. 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.

  20. 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.

  1. Simultaneous Estimation and Validation of Atorvastatin Calcium and Aspirin in Combined Capsule Dosage Form by RP HPLC Method

    Directory of Open Access Journals (Sweden)

    B. V. Suma

    2012-01-01

    Full Text Available A new simple, specific, precise and accurate revere phase liquid chromatography method has been developed for estimation of atorvastatin calcium (AST and ASPIRIN (ASP simultaneously in a combined capsule dosage forms. The chromatographic separation was achieved on a 5 – micron C 18 column (250x 4.6mm using a mobile phase consisting of a mixture of Acetonitrile: Ammonium Acetate buffer 0.02M (68:32 pH 4.5. The flow rate was maintained at 0.8 ml/min. The detection of the constituents was done using UV detector at 245 nm for AST and ASP. The retention time of AST and ASP were found be 4.5915 ± 0.0031 min and 3.282 ±0.0024 min respectively. The developed method was validated for accuracy, linearity, precision, limit of detection (LOD and limit of quantification (LOQ and robustness as per the ICH guidelines.

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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

    2014-07-15

    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.

  8. 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.

  9. 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.

  10. High-resolution bioactivity profiling combined with HPLC-HRMS-SPE-NMR: α-Glucosidase inhibitors and acetylated ellagic acid rhamnosides from Myrcia palustris DC. (Myrtaceae).

    Science.gov (United States)

    Wubshet, Sileshi G; Moresco, Henrique H; Tahtah, Yousof; Brighente, Inês M C; Staerk, Dan

    2015-08-01

    Type 2 diabetes (T2D) is an endocrine metabolic disease with a worldwide prevalence of more than 8%, and an expected increase close to 50% in the next 15-20years. T2D is associated with severe and life-threatening complications like retinopathy, neuropathy, nephropathy, and cardiovascular diseases, and therefore improved drug leads or functional foods containing α-glucosidase inhibitors are needed for management of blood glucose. In this study, leaves of Myrcia palustris were investigated by high-resolution α-glucosidase inhibition profiling combined with HPLC-HRMS-SPE-NMR. This led to identification of casuarinin, myricetin 3-O-β-d-(6″-galloyl)galactopyranoside, kaempferol 3-O-β-d-galactopyranoside, myricetin, and quercetin as α-glucosidase inhibitors. In addition, four acetylated ellagic acid rhamnosides, i.e., 4-O-(2″,4″-O-diacetyl-α-l-rhamnopyranosyl)ellagic acid, 4-O-(2″,3″-O-diacetyl-α-l-rhamnopyranosyl)ellagic acid, 4-O-(3″,4″-O-diacetyl-α-l-rhamnopyranosyl)ellagic acid, and 4-O-(2″,3″,4″-O-triacetyl-α-l-rhamnopyranosyl)ellagic acid were identified.

  11. Determination of Lutein and Zeaxanthin Esters and Their Geometric Isomers in Carotenoid Ester Concentrates Used as Ingredients in Nutritional Supplements: Validation of a Combined Spectrophotometric-HPLC Method.

    Science.gov (United States)

    Lombeida, Wagner O; Rubio, Fernando; Levy, Luis W

    2016-11-01

    A combined spectrophotometric-LC method is described for the determination of total lutein and zeaxanthin ester content in carotenoid ester concentrates, including their main geometrical isomers. The concept of composite-specific absorbance is introduced for this purpose. The method is applicable to carotenoid ester concentrates used as ingredients in oil suspensions and dosage forms. The sample is dissolved in a hexane-2-propanol mixture (95 + 5, v/v) for spectrophotometric measurement at a maximum absorption of ~445 nm. Subsequently, in parallel, a sample is saponified and chromatographed on a normal-phase HPLC column to determine the relative percentage profile of the main geometrical isomers of both carotenoid esters. This, in turn, is used to calculate the composite-specific absorbance of the sample for the final calculation of results. The method, which solely uses reference standards to validate chromatographic conditions, avoids the common error of applying the specific absorbance of only the trans isomer for the calculation of total carotenoid content when cis isomers are present.

  12. Combination HIV prevention among MSM in South Africa: results from agent-based modeling.

    Directory of Open Access Journals (Sweden)

    Ron Brookmeyer

    Full Text Available HIV prevention trials have demonstrated the effectiveness of a number of behavioral and biomedical interventions. HIV prevention packages are combinations of interventions and offer potential to significantly increase the effectiveness of any single intervention. Estimates of the effectiveness of prevention packages are important for guiding the development of prevention strategies and for characterizing effect sizes before embarking on large scale trials. Unfortunately, most research to date has focused on testing single interventions rather than HIV prevention packages. Here we report the results from agent-based modeling of the effectiveness of HIV prevention packages for men who have sex with men (MSM in South Africa. We consider packages consisting of four components: antiretroviral therapy for HIV infected persons with CD4 count <350; PrEP for high risk uninfected persons; behavioral interventions to reduce rates of unprotected anal intercourse (UAI; and campaigns to increase HIV testing. We considered 163 HIV prevention packages corresponding to different intensity levels of the four components. We performed 2252 simulation runs of our agent-based model to evaluate those packages. We found that a four component package consisting of a 15% reduction in the rate of UAI, 50% PrEP coverage of high risk uninfected persons, 50% reduction in persons who never test for HIV, and 50% ART coverage over and above persons already receiving ART at baseline, could prevent 33.9% of infections over 5 years (95% confidence interval, 31.5, 36.3. The package components with the largest incremental prevention effects were UAI reduction and PrEP coverage. The impact of increased HIV testing was magnified in the presence of PrEP. We find that HIV prevention packages that include both behavioral and biomedical components can in combination prevent significant numbers of infections with levels of coverage, acceptance and adherence that are potentially achievable

  13. Establishment of hepatocyte extraction combined with HPLC(HE-HPLC) and application in analysis of active components in the fruits of Gardenia jasminoides extract%肝细胞萃取-HPLC分析法的建立及其在栀子保肝效应物质初步分析中的应用

    Institute of Scientific and Technical Information of China (English)

    洪敏; 马宏宇; 朱荃

    2009-01-01

    目的:建立肝细胞萃取-HPLC分析法(HE-HPLC),并应用其分析栀子中保肝作用的活性成分.方法:应用肝细胞选择性地结合中药提取液中的活性成分,洗去未结合的其他成分后,使细胞靶点失活,被结合的活性成分从肝细胞中释放出来,用高效液相色谱法对这些成分进行分析.结果:可检测到栀子水提液的主要保肝效应成分,初步确定为2个,其中1个为栀子昔,另1个有待进一步鉴定.结论:肝细胞萃取-HPLC 分析法基本可以反映化合物与细胞生物靶点(受体、通道、酶等)的相互作用;该体系中的保留成分和其药理作用有显著的相关性,可用于中药复杂体系物质基础的分析.%To screen effective principles from traditional Chinese medicine, a method named hepatocyte extraction combined with HPLC (HE-HPLC) was establish in this study. The active principles in the fruits of Gardenia jasminoides Ellis extract were combined with the hepatocytes under imitated physiological environments. Then the unattached substances were washed off by PBS with pH 7.4. After that the conjugated compounds were eluted by PBS with pH 4.0. These compounds released from target sites were collected and handled through SPE to be condensed, and analyzed by HPLC. The results indicated that two characteristic active compounds in the fruits of G jasminoides extract binded to the hepatocytes. One of them is geniposide. The other is continued to be identified. It is showed that active principles which could bind to hepotocyte (through receptors, Channels, enzymes, etc.) could be detected, at least partly, by HE-HPLC analysis. There was a significant correlation between the retention properties of the active compounds which was obtained by HE-HPLC and their pharmacological effects on hepotocytes.

  14. 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.

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

    Science.gov (United States)

    Eitsuka, Takahiro; Tatewaki, Naoto; Nishida, Hiroshi; Nakagawa, Kiyotaka; Miyazawa, Teruo

    2016-01-01

    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. PMID:27669218

  16. 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

  17. 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

  18. Preclinical changes in weight of scrapie-infected mice as a function of scrapie agent-mouse strain combination.

    Science.gov (United States)

    Carp, R I; Callahan, S M; Sersen, E A; Moretz, R C

    1984-01-01

    Several inbred strains of mice were injected with different scrapie agents and their total body weight was monitored throughout the incubation period. As a control, mice were injected with normal mouse brain homogenate. For most combinations of scrapie agent and mouse strain, weights during the preclinical phase were similar to or lower than the average weight of controls. For some combinations there was a significant increase in weight (compared to controls) during the latter part of the preclinical phase of disease. The effect was dependent on both agent and mouse strain, i.e., in some cases a mouse strain showed the increase with one scrapie agent but not another and some scrapie agents caused the increase in one inbred strain of mouse but not in another strain. The increase in weight was due to accumulations of fat rather than a generalized increase in weight of various organs. With one mouse strain (SJL), there was increased vacuolation seen in the hypothalamus of mice injected with scrapie agents that showed the increase in weight compared to the lesion intensity with an agent which did not cause the weight increase.

  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. Gold nanoparticles combined with highly expressed amber suppressor tRNA: a future antibacterial agent

    Directory of Open Access Journals (Sweden)

    Xiaoda Song

    2010-10-01

    Full Text Available "nAmber suppressor tRNA is a mutant allele coding for a tRNA, whose anticodon is altered in such a way that the suppressor tRNA inserts an amino acid at an amber codon in translation which leads to suppressing (preventing termination. And some Amber suppressor tRNA strains were found. We propose that gold nanoparticles combined with highly expressed amber suppressor tRNA which can be uptake by cells and recognized by AARS (aminoacyl tRNA synthetase will lead to the formation of C-terminally extended proteins. These proteins probably will not work properly, leading bacteria's death. Because of the difference of tRNA between prokaryotic and eukaryotic cells, even between different bacteria species, this amber suppressor tRNA is orthogonal for other species and cannot be recognized by AARS, therefore has no toxicity to other species. May it be an excellent antibacterial agent in the future? In this article we provide a screening method for the highly expressed amber suppressor tRNA using randomly bases mutation, radioactive selection, activity test in vivo, and finally linkage of the amber suppressor tRNA to gold nanoparticles.

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

    Directory of Open Access Journals (Sweden)

    Gescher Andreas

    2003-01-01

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

  2. 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.

  3. 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.

  4. In vitro synergistic combinations of pentamidine, polymyxin B, tigecycline and tobramycin with antifungal agents against Fusarium spp.

    Science.gov (United States)

    Pozzebon Venturini, Tarcieli; Rossato, Luana; Chassot, Francieli; Tairine Keller, Jéssica; Baldissera Piasentin, Fernanda; Morais Santurio, Janio; Hartz Alves, Sydney

    2016-08-01

    The genus Fusarium is characterized by hyaline filamentous fungi that cause infections predominantly in immunocompromised patients. The remarkable primary resistance to antifungal agents of this genus requires a search for new therapeutic possibilities. This study assessed the in vitro susceptibility of 25 clinical isolates of Fusarium against antifungal agents (amphotericin B, caspofungin, itraconazole and voriconazole) and antimicrobials (pentamidine, polymyxin B, tigecycline and tobramycin) according to the broth microdilution method (M38-A2). The interactions between antifungal and antimicrobial agents were evaluated by the microdilution checkerboard method. Pentamidine and polymyxin B showed MIC values ≥4 µg ml-1 against Fusarium spp. The highest rates of synergism were observed when amphotericin B or voriconazole was combined with tobramycin (80 % and 76 %, respectively), polymyxin B (76 % and 64 %) and pentamidine (72 % and 68 %). The most significant combinations deserve in vivo evaluations in order to verify their potential in the treatment of fusariosis.

  5. 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.

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

    Science.gov (United States)

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

    2014-03-15

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

  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. In vitro and in vivo analysis of antimicrobial agents alone and in combination against multi-drug resistant Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    Songzhe eHE

    2015-05-01

    Full Text Available Objective To investigate the in vitro and in vivo antibacterial activities of tigecycline and other 13 common antimicrobial agents, alone or in combination, against multi-drug resistant Acinetobacter baumannii.MethodsAn in vitro susceptibility test of 101 Acinetobacter baumannii was used to detect minimal inhibitory concentrations (MICs. A mouse lung infection model of multi-drug resistant Acinetobacter baumannii,established by the ultrasonic atomization method, was used to define in vivo antimicrobial activities.Results Multi-drug resistant Acinetobacter baumannii showed high sensitivity to tigecycline (98% inhibition, polymyxin B (78.2% inhibition, and minocycline (74.2% inhibition. However, the use of these antimicrobial agents in combination with other antimicrobial agents produced synergistic or additive effects. In vivo data showed that white blood cell (WBC counts in drug combination groups C (minocycline + amikacin and D (minocycline + rifampicin were significantly higher than in groups A (tigecycline and B (polymyxin B (P < 0.05, after administration of the drugs 24h post-infection. Lung tissue inflammation gradually increased in the model group during the first 24h after ultrasonic atomization infection; vasodilation, congestion with hemorrhage were observed 48h post infection. After three days of anti-infective therapy in groups A, B, C and D, lung tissue inflammation in each group gradually recovered with clear structures. The mortality rates in drug combination groups (groups C and D were much lower than in groups A and B.ConclusionThe combination of minocycline with either rifampicin or amikacin is more effective against multidrug-resistant Acinetobacter baumannii than single-agent tigecycline or polymyxin B. In addition, the mouse lung infection by ultrasonic atomization is a suitable model for drug screening and analysis of infection mechanism.

  9. Combined microplate-ABTS and HPLC-ABTS analysis of tomato and pepper extracts reveals synergetic and antagonist effects of their lipophilic antioxidative components.

    Science.gov (United States)

    Le Grandois, Julie; Guffond, Delphine; Hamon, Erwann; Marchioni, Eric; Werner, Dalal

    2017-05-15

    The antioxidant capacity of 9 pure lipophilic compounds was examined by microplate-ABTS and HPLC-ABTS, using similar experimental conditions. Results obtained showed that HPLC-ABTS method can be used for a rapid determination of individual antioxidant capacity of compounds in standard solutions or complex mixtures. The application of both methods to real lipophilic extracts from tomato (Solanum lycopersicum L.), green and red peppers (Capsicum annuum) reveals possible interactions between antioxidants. Thus, synthetic mixtures of two compounds identified in tomato and peppers were measured using microplate-ABTS and HPLC-ABTS. Synergistic effects were observed between (β-carotene-capsanthin) (1:9) and (1:1), (α-tocopherol-capsanthin) (1:9), (lutein-lycopene) (9:1) and (capsanthin-δ-tocopherol) (9:1). On the contrary, antagonistic effects were observed for (lutein-δ-tocopherol) and (α-tocopherol-δ-tocopherol). The interactions observed with two-compound mixtures are not systematically observed in the natural lipophilic extracts from tomato, green and red peppers, probably since extracts are more complex and are susceptible to cause interferences.

  10. Percutaneous exposure to the nerve agent VX: Efficacy of combined atropine, obidoxime and diazepam treatment

    NARCIS (Netherlands)

    Joosen, M.J.A.; Schans, M.J. van der; Helden, H.P.M. van

    2010-01-01

    The nerve agent VX is most likely to enter the body via liquid contamination of the skin. After percutaneous exposure, the slow uptake into the blood, and its slow elimination result in toxic levels in plasma for a period of several hours. Consequently, this has implications for the development of t

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

    NARCIS (Netherlands)

    Silaghi, G.; Robu, V.

    2005-01-01

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

  12. 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.

  13. 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.

  14. A numerical study of combined use of two biocontrol agents with different biocontrol mechanisms in controlling foliar pathogens.

    Science.gov (United States)

    Xu, X-M; Jeffries, P; Pautasso, M; Jeger, M J

    2011-09-01

    Effective use of biocontrol agents is an important component of sustainable agriculture. A previous numerical study of a generic model showed that biocontrol efficacy was greatest for a single biocontrol agent (BCA) combining competition with mycoparasitism or antibiosis. This study uses the same mathematical model to investigate whether the biocontrol efficacy of combined use of two BCAs with different biocontrol mechanisms is greater than that of a single BCA with either or both of the two mechanisms, assuming that two BCAs occupy the same host tissue as the pathogen. Within the parameter values considered, a BCA with two biocontrol mechanisms always outperformed the combined use of two BCAs with a single but different biocontrol mechanism. Similarly, combined use of two BCAs with a single but different biocontrol mechanism is shown to be far less effective than that of a single BCA with both mechanisms. Disease suppression from combined use of two BCAs was very similar to that achieved by the more efficacious one. As expected, a higher BCA introduction rate led to increased disease suppression. Incorporation of interactions between two BCAs did not greatly affect the disease dynamics except when a mycoparasitic and, to a lesser extent, an antibiotic-producing BCA was involved. Increasing the competitiveness of a mycoparasitic BCA over a BCA whose biocontrol mechanism is either competition or antibiosis may lead to improved biocontrol initially and reduced fluctuations in disease dynamics. The present study suggests that, under the model assumptions, combined use of two BCAs with different biocontrol mechanisms in most cases only results in control efficacies similar to using the more efficacious one alone. These predictions are consistent with published experimental results, suggesting that combined use of BCAs should not be recommended without clear understanding of their main biocontrol mechanisms and relative competitiveness, and experimental evaluation.

  15. 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.

  16. 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.

  17. Characterization of taste-active fractions in red wine combining HPLC fractionation, sensory analysis and ultra performance liquid chromatography coupled with mass spectrometry detection.

    Science.gov (United States)

    Sáenz-Navajas, María-Pilar; Ferreira, Vicente; Dizy, Marta; Fernández-Zurbano, Purificación

    2010-07-19

    Five Tempranillo wines exhibiting marked differences in taste and/or astringency were selected for the study. In each wine the non-volatile extract was obtained by freeze-drying and further liquid extraction in order to eliminate remaining volatile compounds. This extract was fractionated by semipreparative C18-reverse phase-high performance liquid chromatography (C18-RP-HPLC) into nine fractions which were freeze-dried, reconstituted with water and sensory assessed for taste attributes and astringency by a specifically trained sensory panel. Results have shown that wine bitterness and astringency cannot be easily related to the bitter and astringent character of the HPLC fractions, what can be due to the existence of perceptual and physicochemical interactions. While the bitter character of the bitterest fractions may be attributed to some flavonols (myricetin, quercetin and their glycosides) the development of a sensitive UPLC-MS method to quantify astringent compounds present in wines has made it possible to demonstrate that proanthocyanidins monomers, dimers, trimers and tetramers, both galloylated or non-galloylated are not relevant compounds for the perceived astringency of the fractions, while cis-aconitic acid, and secondarily vainillic, and syringic acids and ethyl syringate, are the most important molecules driving astringency in two of the fractions (F5 and F6). The identity of the chemicals responsible for the astringency of the third fraction could be assigned to some proanthocyanidins (higher than the tetramer) capable to precipitate with ovalbumin.

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

    Science.gov (United States)

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

    2007-05-01

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

  19. Distributed Optimal Economic Dispatch Based on Multi-Agent System Framework in Combined Heat and Power Systems

    Directory of Open Access Journals (Sweden)

    Yu-Shuai Li

    2016-10-01

    Full Text Available In this paper, a novel distributed method is presented to solve combined heat and power economic dispatch problem, which is formulated as a distributed coupled optimization problem. The optimization goal is achieved by establishing two modified consensus protocols with two corresponding feedback parts while satisfying the electrical and heat supply–demand balance. Moreover, an alternating iterative method is proposed to handle the heat-electrical coupling problem existed in the objective function and the feasible operating regions. In addition, the proposed distributed method is implemented by a multi-agent system framework, which only requires local information exchange among neighboring agents. Simulation results obtained on a 16-bus test system are provided to illustrate the effectiveness of the proposed distributed method.

  20. 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.

  1. 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.

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

    Science.gov (United States)

    Mohd Hasan, Mohd Rosli

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

  3. Characteristic fingerprint based on gingerol derivative analysis for discrimination of ginger (Zingiber officinale) according to geographical origin using HPLC-DAD combined with chemometrics.

    Science.gov (United States)

    Yudthavorasit, Soparat; Wongravee, Kanet; Leepipatpiboon, Natchanun

    2014-09-01

    Chromatographic fingerprints of gingers from five different ginger-producing countries (China, India, Malaysia, Thailand and Vietnam) were newly established to discriminate the origin of ginger. The pungent bioactive principles of ginger, gingerols and six other gingerol-related compounds were determined and identified. Their variations in HPLC profiles create the characteristic pattern of each origin by employing similarity analysis, hierarchical cluster analysis (HCA), principal component analysis (PCA) and linear discriminant analysis (LDA). As results, the ginger profiles tended to be grouped and separated on the basis of the geographical closeness of the countries of origin. An effective mathematical model with high predictive ability was obtained and chemical markers for each origin were also identified as the characteristic active compounds to differentiate the ginger origin. The proposed method is useful for quality control of ginger in case of origin labelling and to assess food authenticity issues.

  4. 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.

  5. Anti-tumor effect of a novel soluble recombinant human endostatin: administered as a single agent or in combination with chemotherapy agents in mouse tumor models.

    Directory of Open Access Journals (Sweden)

    Zhihua Ren

    Full Text Available Angiogenesis has become an attractive target in cancer treatment. Endostatin is one of the potent anti-angiogenesis agents. Its recombinant form expressed in the yeast system is currently under clinical trials. Endostatin suppresses tumor formation through the inhibition of blood vessel growth. It is anticipated that combined therapy using endostatin and cytotoxic compounds may exert an additive effect. In the present study, we expressed and purified recombinant human endostatin (rhEndostatin that contained 3 additional amino acid residues (arginine, glycine, and serine at the amino-terminus and 6 histidine residues in its carboxyl terminus. The recombinant protein was expressed in E. Coli and refolded into a soluble form in a large scale purification process. The protein exhibited a potent anti-tumor activity in bioassays. Furthermore, rhEndostatin showed an additive effect with chemotherapy agents including cyclophosphamide (CTX and cisplatin (DDP.rhEndostatin cDNA was cloned into PQE vector and expressed in E. Coli. The protein was refolded through dialysis with an optimized protocol. To establish tumor models, nude mice were subcutaneously injected with human cancer cells (lung carcinoma A549, hepatocellular carcinoma QGY-7703, or breast cancer Bcap37. rhEndostatin and/or DDP was administered peritumorally to evaluate the rate of growth inhibition of A549 tumors. For the tumor metastasis model, mice were injected intravenously with mouse melanoma B16 cells. One day after tumor cell injection, a single dose of rhEndostatin, or in combination with CTX, was administered intravenously or at a site close to the tumor.rhEndostatin reduced the growth of A549, QGY-7703, and Bcap37 xenograft tumors in a dose dependent manner. When it was administered peritumorally, rhEndostatin exhibited a more potent inhibitory activity. Furthermore, rhEndostatin displayed an additive effect with CTX or DDP on the inhibition of metastasis of B16 tumors or growth of

  6. Combination therapy with biologic agents in rheumatic diseases: current and future prospects

    Science.gov (United States)

    Inui, Kentaro; Koike, Tatsuya

    2016-01-01

    Strategies in rheumatoid arthritis (RA) based on ‘treat to target’ aim to control disease activity, minimize structural damage, and promote longer life. Several disease-modifying antirheumatic drugs (DMARDs) have been shown to be effective including biological DMARDs (bDMARDs). Treatment guidelines and recommendations for RA have also been published. According to those guidelines, conventional synthetic DMARDs (csDMARDs), as monotherapy or combination therapy, should be used in DMARD-naïve patients, irrespective of the addition of glucocorticoids (GCs). Combination therapies with bDMARDs are also essential for conducting treatment strategies for RA, because in every recommendation or guideline for the management of RA, combination therapies of csDMARDs with bDMARDs are recommended for RA patients with moderate or high disease activity after failure of csDMARD treatment. bDMARDs are more efficacious if used concomitantly with methotrexate (MTX) than with MTX monotherapy or bDMARD monotherapy. Thus, retention has been reported to be longer when combined with MTX. The superior efficacy of combination therapy compared with MTX monotherapy or bDMARD monotherapy could be because: (1) it could help to minimize MTX toxicity by reducing the dose of MTX, thus retention rate of the same therapeutic regimen would become high; (2) anti-bDMARD antibodies are observed at lower concentrations when using MTX concomitantly, so less clearance of bDMARDs via less formation of bDMARD and an anti-bDMARD immune complex; (3) of the additive effects of MTX to bDMARD, especially the combination of tumor necrosis factor inhibitors (TNFis) with MTX. Hence, evidence suggests that combination therapy with bDMARDs is more efficacious than monotherapy using a csDMARD or bDMARD, and that MTX is the best drug for this purpose (if MTX is not contraindicated). Finding the most effective drug regimen at the lowest cost will be the aim of RA treatment in the future. PMID:27721905

  7. Bimodal Imaging Probes for Combined PET and OI: Recent Developments and Future Directions for Hybrid Agent Development

    Directory of Open Access Journals (Sweden)

    Uwe Seibold

    2014-01-01

    Full Text Available Molecular imaging—and especially positron emission tomography (PET—has gained increasing importance for diagnosis of various diseases and thus experiences an increasing dissemination. Therefore, there is also a growing demand for highly affine PET tracers specifically accumulating and visualizing target structures in the human body. Beyond the development of agents suitable for PET alone, recent tendencies aim at the synthesis of bimodal imaging probes applicable in PET as well as optical imaging (OI, as this combination of modalities can provide clinical advantages. PET, due to the high tissue penetration of the γ-radiation emitted by PET nuclides, allows a quantitative imaging able to identify and visualize tumors and metastases in the whole body. OI on the contrary visualizes photons exhibiting only a limited tissue penetration but enables the identification of tumor margins and infected lymph nodes during surgery without bearing a radiation burden for the surgeon. Thus, there is an emerging interest in bimodal agents for PET and OI in order to exploit the potential of both imaging techniques for the imaging and treatment of tumor diseases. This short review summarizes the available hybrid probes developed for dual PET and OI and discusses future directions for hybrid agent development.

  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. Fishing and knockout of bioactive compounds using a combination of high-speed counter-current chromatography (HSCCC) and preparative HPLC for evaluating the holistic efficacy and interaction of the components of Herba Epimedii.

    Science.gov (United States)

    Jin, Jing; Li, Yubo; Kipletting Tanui, Emmanuel; Han, Liwen; Jia, Yuan; Zhang, Lu; Wang, Yuming; Zhang, Xiuxiu; Zhang, Yanjun

    2013-05-20

    Due to the complex chemical compositions and pharmacological effects of traditional Chinese medicines, we developed a strategy based on fishing and knockout of bioactive compounds using a combination of high-speed counter-current chromatography (HSCCC) and preparative HPLC for evaluating the holistic activity and interaction of the components of Herba Epimedii. First, osteoblast target cell extraction was used for preliminary screening of the potential bioactive compounds of Herba Epimedii. Second, the bioactive compounds identified (epimedin A, epimedin B, epimedin C and icariin) were fished and knocked out using high-speed counter-current chromatography and preparative HPLC. Third, the bioactivity of resulting fractions was assessed by determining their influence on cell proliferation and differentiation, thereby allowing for an evaluation of their interaction.The pharmacodynamic contribution ratio of each bioactive compound to the efficacy of the herbal medicine could then be comprehensively and intuitively determined based on the spectra-activity correlations (VIP values) of the tested compositions using partial least-squares regression (PLS-R), through which the reliability of the screening and isolation of bioactive compounds by the target cell extraction technique were verified. The proposed strategy is a useful approach with potential application in other traditional Chinese medicines.

  10. 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.

  11. Canagliflozin: Efficacy and Safety in Combination with Metformin Alone or with Other Antihyperglycemic Agents in Type 2 Diabetes.

    Science.gov (United States)

    Qiu, Rong; Balis, Dainius; Capuano, George; Xie, John; Meininger, Gary

    2016-12-01

    Metformin is typically the first pharmacologic treatment recommended for type 2 diabetes mellitus (T2DM), but many patients do not achieve glycemic control with metformin alone and eventually require combination therapy with other agents. Canagliflozin, a sodium glucose co-transporter 2 (SGLT2) inhibitor, was assessed in a comprehensive Phase 3 clinical development program consisting of ~10,000 participants, of which ~80% were on background therapy that consisted of metformin alone or in combination with other antihyperglycemic agents (AHAs; e.g., pioglitazone, sulfonylurea, and insulin). In addition, the efficacy and safety of canagliflozin and metformin as the initial combination therapy and canagliflozin monotherapy were assessed versus metformin in treatment-naïve patients with T2DM. Across studies in patients with T2DM who were on metformin alone or in combination with other AHAs, canagliflozin 100 and 300 mg provided improvements in glycated hemoglobin for up to 104 weeks. Canagliflozin was also associated with reductions in body weight and systolic blood pressure when added to background therapy consisting of metformin alone or with other AHAs. Canagliflozin was generally well tolerated, with increased incidence of adverse events (AEs) related to the mechanism of SGLT2 inhibition (i.e., genital mycotic infections, urinary tract infections, and osmotic diuresis-related AEs). Consistent with its insulin-independent mechanism of action, canagliflozin was associated with low rates of hypoglycemia when background therapy did not include sulfonylurea or insulin. Due to its favorable efficacy and safety profile, these results suggest that adding canagliflozin to a background regimen consisting of metformin or implementing treatment with a fixed-dose regimen of canagliflozin and metformin would provide an effective and safe treatment regimen for T2DM management.

  12. Percutaneous exposure to the nerve agent VX: Efficacy of combined atropine, obidoxime and diazepam treatment.

    Science.gov (United States)

    Joosen, Marloes J A; van der Schans, Marcel J; van Helden, Herman P M

    2010-10-06

    The nerve agent VX is most likely to enter the body via liquid contamination of the skin. After percutaneous exposure, the slow uptake into the blood, and its slow elimination result in toxic levels in plasma for a period of several hours. Consequently, this has implications for the development of toxic signs and for treatment onset. In the present study, clinical signs, toxicokinetics and effects on respiration, electroencephalogram and heart rate were investigated in hairless guinea pigs after percutaneous exposure to 500 microg/kg VX. We found that full inhibition of AChE and partial inhibition of BuChE in blood were accompanied by the onset of clinical signs, reflected by a decline in respiratory minute volume, bronchoconstriction and a decrease in heart rate. Furthermore, we investigated the therapeutic efficacy of a single dose of atropine, obidoxime and diazepam, administered at appearance of first clinical signs, versus that of repetitive dosing of these drugs on the reappearance of signs. A single shot treatment extended the period to detrimental physiological decline and death for several hours, whereas repetitive administration remained effective as long as treatment was continued. In conclusion, percutaneous VX poisoning showed to be effectively treatable when diagnosed on time and when continued over the entire period of time during which VX, in case of ineffective decontamination, penetrates the skin.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. Residue and dissipation kinetics of thiamethoxam in a vegetable-field ecosystem using QuEChERS methodology combined with HPLC-DAD.

    Science.gov (United States)

    Abd-Alrahman, Sherif H

    2014-09-15

    The dissipation kinetics and residual levels of thiamethoxam in potato and soil under field ecosystem were determined using a QuEChERS method with HPLC-DAD. At fortification levels of 0.05, 0.1, 0.25, 0.5, 1.0 and 5.0 mg kg(-1), it was shown recovery was 99.4% (95.3-103.5%) for potato tubers, and 88.5% (86-91%) for soil with coefficient variation of the method (CV%) was less than 4% in potato tubers, and in soil less than 11%. For repeatability ranged from 1.27% to 4.77%. The LOD and LOQ were estimated to be 0.02 and 0.06 mg kg(-1), respectively. The half-lives were 2.92 and 1.4 days, respectively. The terminal residues of thiamethoxam were below the maximum residue limit (MRL 0.2 mg kg(-1)) after 6 days, which considered to be safe for human beings. These results contribute to establishing the scientific basis of the dosage of thiamethoxam for use in vegetable-field ecosystems.

  19. Characterization of flavonoids and phenolic acids in Myrcia bella Cambess. using FIA-ESI-IT-MS(n) and HPLC-PAD-ESI-IT-MS combined with NMR.

    Science.gov (United States)

    Saldanha, Luiz L; Vilegas, Wagner; Dokkedal, Anne L

    2013-07-16

    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-MS(n) 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.

  20. 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.

  1. 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.

  2. Application of differential scanning calorimetry (DSC), HPLC and pNMR for interpretation primary crystallisation caused by combined low and high melting TAGs.

    Science.gov (United States)

    Saadi, Sami; Ariffin, Abdul Azis; Ghazali, Hasanah Mohd; Miskandar, Mat Sahri; Boo, Huey Chern; Abdulkarim, Sabo Mohammed

    2012-05-01

    The main goal of the present work was to assess the mechanism of crystallisation, more precisely the dominant component responsible for primary crystal formations and fat agglomerations. Therefore, DSC results exhibited significant effect on temperature transition; peak sharpness and enthalpy at palm stearin (PS) levels more than 40wt.%. HPLC data demonstrated slight reduction in the content of POO/OPO at PS levels less than 40wt.%, while the excessive addition of PS more than 40wt.% increased significantly PPO/POP content. The pNMR results showed significant drop in SFC for blends containing PS less than 40wt.%, resulting in low SFC less than 15% at body temperature (37°C). Moreover, the values of viscosity (η) and shear stress (τ) at PS levels over 40wt.% expressed excellent internal friction of the admixtures. All the data reported indicate that PPO/POP was the major component of primary nucleus developed. In part, the levels of PS should be less than 40wt.%, if these blends are designed to be used for margarine production.

  3. 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.

  4. Microwave-assisted extraction in combination with HPLC-UV for quantitative analysis of six bioactive oxoisoaporphine alkaloids in Menispermum dauricum DC.

    Science.gov (United States)

    Wei, Jinxia; Chen, Jing; Liang, Xinlei; Guo, Xingjie

    2016-02-01

    A novel and reliable method based on microwave-assisted extraction (MAE) followed by HPLC-UV was developed and validated for the simultaneous quantification of six pharmacologically important oxoisoaporphine alkaloids in the total plants of Menispermum dauricum DC. The optimal MAE extraction condition was performed at 60°C for 11 min with ethanol-water (70:30, v/v) as the extracting solvent, and the solvent to solid ratio was 20:1. Chromatographic separation was achieved on a reversed-phase YMC C18 column (250 × 4.6 mm, i.d., 5 µm) with a gradient mobile phase consisting of A (1% aqueous formic acid) and B (acetonitrile containing 1% formic acid) at a flow rate of 1.5 mL/min. The detection wavelength was set at 422 nm. Excellent linearity over the investigated concentration ranges was observed with values of r >0.999 for all analytes. The method developed was validated with acceptable sensitivity, intra- and inter-day precision and extraction recoveries. It was successfully applied to the determination of six alkaloids in Menispermum dauricum DC from different sources and different parts of Menispermum dauricum DC. The results obtained indicated that the method is suitable for the quality control of Menispermum dauricum DC.

  5. 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.

  6. Determination of trace triclosan in environmental water by microporous bamboo-activated charcoal solid-phase extraction combined with HPLC-ESI-MS.

    Science.gov (United States)

    Sun, Jing; Yi, Chun-Liang; Zhao, Ru-Song; Wang, Xia; Jiang, Wen-Qiang; Wang, Xi-Kui

    2012-10-01

    A sensitive and efficient analytical method for triclosan (TCS) determination in water, which involves enrichment with bamboo-activated charcoal and detection with HPLC-ESI-MS, was developed. The influence of several operational parameters, including the eluant and its volume, the flow rate, the volume andacidity of the sample, and the amount of bamboo-activated charcoal, were investigated and optimized. Under the optimum conditions, linearity of the method was observed in the range of 0.02-20 μg/L, with correlation coefficients (r(2) ) >0.9990. The limit of detection was 0.002 μg/L based on the ratio of chromatographic signal to baseline noise (S/N = 3). The spiked recoveries of TCS in real water samples were achieved in the range of 97.6-112.5%. The proposed method was applied to analyze TCS in real aqueous samples. All the surface water samples collected in Xiaoqing River had detectable levels of TCS with concentrations of 42-197 ng/L.

  7. 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

  8. 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

  9. Combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with photodiode array detector (HPLC-DAD) in systematic toxicological analysis.

    Science.gov (United States)

    Broecker, Sebastian; Pragst, Fritz; Bakdash, Abdulsallam; Herre, Sieglinde; Tsokos, Michael

    2011-10-10

    Time of flight mass spectrometry provides new possibilities of substance identification by determination of the molecular formula from accurate molecular mass and isotope pattern. However, the huge number of possible isomers requires additional evidence. As a suitable way for routine performance of systematic toxicological analysis, a method for combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with diode array detector (HPLC-DAD) was developed and applied to blood samples from 77 death cases. The blood samples were prepared by extraction with CH(2)Cl(2) and by protein precipitation with acetonitrile (1:4 (v/v)). The evaporated extracts were reconstituted in 35% acetonitril/0.1% formic acid/H(2)O and aliquots were injected for analysis by LC-QTOF-MS (Agilent 6530) and HPLC-DAD (Agilent 1200). A valve switching system enabled simultaneous operation of both separated chromatographic lines under their respective optimal conditions using the same autosampler. The ESI-QTOF-MS instrument was run in data dependent acquisition mode with switching between MS and MS/MS (cycle time 1.1s) and measuring the full mass spectra and the collision induced dissociation (CID) fragment spectra of all essential [M+H](+) ions. Libraries of accurate mass CID spectra (~2500 substances) and of DAD-UV spectra (~3300 substances) of the authors were used for substance identification. The application of this procedure is demonstrated in detail at four examples with multiple drug intake or administration. In the 77 cases altogether 198 substances were identified (87 by DAD and 195 by QTOF-MS) with a frequency between 1 and 20. In practical application, the sample preparation proved to be suitable for both techniques and for a wide variety of substances with different polarity. The automatic performance of the measurements was efficient and robust. Mutual confirmation, decrease of false positive and

  10. Simultaneous investigation of sesquiterpenes, pyrrolizidine alkaloids and N-oxides in Butterbur (Petasites hybridus) with an offline 2D-combination of HPLC-UV and LC-MMI-ToF-MS.

    Science.gov (United States)

    Aydın, Ahmet Alper; Letzel, Thomas

    2013-11-01

    With the worldwide rapid increasing interest in the use of natural products as dietary supplements, medical remedies and functional foods, it has been accepted that omitting the plant constituents with potential adverse effects was a huge fault of the past. Several countries developed regulations to limit the consumption of such products in the markets. Among these natural products, butterbur (Petasites) has been used for years as herbal supplement for its anti-spasmodic and anti-inflammatory effects. However, its hepatotoxic alkaloid content limits the direct usage. In this study, investigation of sesquiterpenes and pyrrolizidine alkaloids (PAs) together with their N-oxide forms has been conducted with an offline 2D-combination using high-performance liquid chromatography with UV detection (HPLC-UV) and liquid chromatography - multi mode ionization - time-of-flight mass spectrometry (LC-MMI-ToF-MS) for plant screening. The content has been qualitatively investigated to provide information on the constituents of the plant rhizomes extracted using ethanol. Besides the reported hepatotoxic and medically bio-active plant constituents, a strategy has been suggested for estimating the retention order and retention times with respect to calculated logD (distribution coefficient) and hydrophobicity distributions on C18 reversed-phase column when all standard compounds are not available in laboratory. In this sense, the influence of calculated logD and hydrophobicity distributions on retention time has been clarified via available PA and PA-N-oxide standards. The ethanolic extract of Petasites hybridus has been used for examination of the strategy in a real-sample model. Additionally, the advantages of the developed HPLC-UV and LC-MMI-ToF-MS combination have been discussed with respect to the presented results.

  11. Miniaturized salting-out liquid-liquid extraction in a coupled-syringe system combined with HPLC-UV for extraction and determination of sulfanilamide.

    Science.gov (United States)

    Sereshti, Hassan; Khosraviani, Marzieh; Sadegh Amini-Fazl, Mohammad

    2014-04-01

    In salting-out liquid-liquid extraction (SALLE) technique, water-miscible organic solvents are used for extraction of polar analytes from saline solutions. In this study, for the first time, a coupled 1-mL syringes system was utilized to perform a miniaturized SALLE method. Sulfanilamide antibiotic was extracted and determined via the developed method followed by high performance liquid chromatography-ultraviolet detection (HPLC-UV). The extraction process was carried out by rapid shooting of acetonitrile as extraction solvent (syringe B) into saline aqueous sample solution (syringe A), and then the shooting was repeated several times at a rate of 1 cycles(-1). Thereby, an extremely large contact surface area was created between phases and led to a rapid equilibrium and mass transfer. In order to improve the efficiency of the method, the effect of extraction solvent (type and volume), shooting times, salt concentration, and pH on the extraction efficiency was investigated. The best performance of the method was achieved with 250 µL of acetonitrile, salt concentration of 250 mg mL(-1), pH of 7, and shooting times of 5. The linear dynamic range was 0.001-10 µg mL(-1) with the determination coefficient of 0.9999. The relative standard deviation (RSD; n=3, C=5 µg mL(-1)), and the limit of detection (LOD) were 1.55% and 0.3 ng mL(-1), respectively. The developed technique was successfully applied to genuine samples of tea, water, milk, honey, human urine, plasma and blood.

  12. The neurobiology of bipolar disorder: identifying targets for specific agents and synergies for combination treatment.

    Science.gov (United States)

    Andreazza, Ana C; Young, L Trevor

    2014-07-01

    Bipolar disorder (BD) is a chronic psychiatric illness described by severe changes in mood. Extensive research has been carried out to understand the aetiology and pathophysiology of BD. Several hypotheses have been postulated, including alteration in genetic factors, protein expression, calcium signalling, neuropathological alteration, mitochondrial dysfunction and oxidative stress in BD. In the following paper, we will attempt to integrate these data in a manner which is to understand targets of treatment and how they may be, in particular, relevant to combination treatment. In summary, the data suggested that BD might be associated with neuronal and glial cellular impairment in specific brain areas, including the prefrontal cortex. From molecular and genetics: (1) alterations in dopaminergic system, through catechol-O-aminotransferase; (2) decreased expression and polymorphism on brain-derived neurotrophic factor; (3) alterations cyclic-AMP responsive element binding; (4) dysregulation of calcium signalling, including genome-wide finding for voltage-dependent calcium channel α-1 subunit are relevant findings in BD. Future studies are now necessary to understand how these molecular pathways interact and their connection to the complex clinical manifestations observed in BD.

  13. 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.

  14. Combined Effect of Some Bio-Agents on the Grasshopper, Hetiracris littoralis Under Semi-Field Condition

    Directory of Open Access Journals (Sweden)

    Aziza Sharaby

    2013-06-01

    Full Text Available LC50 of the alchoholic-80% extract of Euphorbia pulchrrima (0.714%, essential oil of Garlic plant Allium sativum (0.067% and nematodes of Steinernima sp. and Heterorhabditis sp. (500 IJs/ml, were tested for their solely and/or combined toxic effects and for their effects on some biological aspects against the grasshopper, Heteracris littoralis 1st instar nymphs under semi-field condition. The joint action of the mixture of the most effective extract (E. pulchrrima and oil (Garlic oil exhibit an antagonistic effect with co-toxicity index of (–24, despite the increase the proportion of death in the mixture for all the tested groups the type of interaction were antagonism, all the tested materials had variable mode of action which resulted in significantly antagonistic effects. Euphorbia 80% methanol extract and Garlic oil may use separately or in combination as alternatives safe tools against H. littoralis grasshopper. Semi-field experiments cleared that nematodes in combination with the oil or extract increased the mortality percentage. The combination mixture of extract, oil and nematode significantly affected development, reproduction and life cycle of H. littoralis. Lethal effect varied with regard to the nematode species. Semi-field experiment of the plant extract, plant oil and their mixture revealed some changes on the biological aspects, an increase in the nymphal period, pre-oviposition, oviposition and post-oviposition periods. There is vigorous decrease in the female fecundity and fertility. The control of the insect by nematode and sub-lethal dose of plant extract or plant volatile oil as biological control may enhance their lethal effect on insect pest when applied simultaneously. Combination mixture of the tested bio-agent could be considered as possible means for use in programs of integrated pest management of H. littoralis grasshopper.

  15. Combining insulins with oral antidiabetic agents: effect on hyperglycemic control, markers of cardiovascular risk and disease

    Directory of Open Access Journals (Sweden)

    Kjeld Hermansen

    2008-06-01

    Full Text Available Kjeld Hermansen, Lene Sundahl Mortensen, Marie-Louise HermansenDepartment of Endocrinology and Metabolism C, Aarhus University Hospital, DK-8000 Aarhus, DenmarkAbstract: Patients with type 2 diabetes mellitus (T2DM have an increased risk of cardiovascular disease (CVD. Unfortunately, several potential barriers exist for CVD risk management in diabetes, including the need for significant lifestyle changes, potential problems with hypoglycemia, weight gain, injection tolerability, treatment complexity with current diabetes therapies and other, unmodifiable factors. Improving glycemic control may impact CVD risk. Treatment of T2DM usually starts with lifestyle changes such as diet and exercise. When these become insufficient, pharmacotherapy is required. Various oral antidiabetic drugs (OADs are available that reduce hyperglycemia. The first line of therapy is usually metformin, since it does not increase weight and seems to have a beneficial effect on CVD mortality and risk factors. As T2DM progresses, insulin treatment becomes necessary for the majority of patients. The last few years have seen the development of long-acting, rapid-acting, and premixed insulin analog formulations. The treat-to-target algorithms of recent studies combining OADs plus insulin analogs have demonstrated that patients can reach glycemic treatment targets with low risk of hypoglycemia, greater convenience, and – with some analogs – limited weight gain vs conventional insulins. These factors may possibly have a positive influence on CVD risk. Future studies will hopefully elucidate the benefits of this approach.Keywords: diabetes mellitus, type 2 diabetes, cardiovascular disease, hyperglycemia, insulin, oral antidiabetic drugs

  16. Solubilization of proteins in aqueous two-phase extraction through combinations of phase-formers and displacement agents.

    Science.gov (United States)

    Kress, Christian; Sadowski, Gabriele; Brandenbusch, Christoph

    2017-03-01

    The aqueous two-phase extraction (ATPE) of therapeutic proteins is a promising separation alternative to cost-intensive chromatography, still being the workhorse of nowadays downstream processing. As shown in many publications, using NaCl as displacement agent in salt-polymer ATPE allows for a selective purification of the target protein immunoglobulin G (IgG) from human serum albumin (HSA, represents the impurity). However a high yield of the target protein is only achievable as long as the protein is stabilized in solution and not precipitated. In this work the combined influence of NaCl and polyethylene glycol (Mw=2000g/mol) on the IgG-IgG interactions was determined using composition gradient multi-angle light scattering (CG-MALS) demonstrating that NaCl induces a solubilization of IgG in polyethylene glycol 2000 solution. Moreover it is shown that the displacement agent NaCl has a significant and beneficial influence on the IgG solubility in polyethyleneglycol2000-citrate aqueous two-phase system (ATPS) which can also be accessed by these advanced B22 measurements. By simultaneous consideration of IgG solubility data with results of the ATPS phase behavior (especially volume fraction of the respective phases) allows for the selection of process tailored ATPS including identification of the maximum protein feed concentration. Through this approach an ATPS optimization is accessible providing high yields and selectivity of the target protein (IgG).

  17. 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.

  18. 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.

  19. In vitro activity of lauric acid or myristylamine in combination with six antimicrobial agents against methicillin-resistant Staphylococcus aureus (MRSA).

    Science.gov (United States)

    Kitahara, Takashi; Aoyama, Yuko; Hirakata, Yoichi; Kamihira, Shimeru; Kohno, Shigeru; Ichikawa, Nobuhiro; Nakashima, Mikiro; Sasaki, Hitoshi; Higuchi, Shun

    2006-01-01

    The objective of this study was to investigate the in vitro activities of lauric acid and myristylamine in combination with six antimicrobial agents against methicillin-resistant Staphylococcus aureus (MRSA). The combination effect of lipids and antimicrobial agents was evaluated by the checkerboard method to obtain a fractional inhibitory concentration (FIC) index. The effects of lauric acid + gentamicin (GM) and lauric acid + imipenem (IPM) combinations were synergistic against the clinical isolates in 12 combinations. An antagonistic FIC index was observed only with the myristylamine + GM combination. We investigated in detail the antimicrobial activity for two combinations that showed a synergistic effect. The cytotoxicity of lauric acid was not enhanced by the addition of GM and IPM. In time-kill studies, lauric acid + GM and lauric acid + IPM combinations at one-eighth of the minimum inhibitory concentration produced a bacteriostatic effect.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

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

    DEFF Research Database (Denmark)

    Liu, Yueqiu; Nielsen, Mia; Stærk, Dan

    2014-01-01

    Bacillus subtilis, Staphylococcus aureus, Escherichia coli or Pseudomonas aeruginosa. The biochromatograms demonstrated that tannins play a main role for the bacterial growth inhibition observed for all above-mentioned plants except for Polygonum cuspidatum. Furthermore, the high-resolution bacterial...... growth inhibition profiling combined with HPLC–HRMS–SPE–NMR allowed fast identification of three non-tannin active compounds, i.e., piceid, resveratrol and emodin from ethanol extract of Polygonum cuspidatum. Conclusion The high-resolution bacterial growth inhibition profiling allowed fast pinpointing...... of constituents responsible for the bioactivity, e.g., either showing tannins being the main bacterial growth inhibitors as observed for the majority of the active plants, or combined with HPLC–HRMS–SPE–NMR for fast structural identification of non-tannin constituents correlated with antibacterial activity....

  5. Separation and direct detection of long chain fatty acids and their methylesters by the non-aqueous reversed phase HPLC and Silver Ion Chromotography, combined with CO laser pumped thermal lens spectrometry

    NARCIS (Netherlands)

    Bicanic, D.D.; Mocnik, G.; Franko, M.; Niederlander, H.A.G.; Bovenkamp, van de P.; Cozijnsen, J.L.; Klift, van der E.J.C.

    2006-01-01

    The potential of the CO laser pumped dual beam thermal lens spectrometer (TLS) used as the detector of infrared (IR) absorbance in non-aqueous reversed-phase high pressure liquid chromatography (NARP-HPLC) and argentation chromatography (Ag-HPLC-TLS) has been investigated. The linoleic acid C18:2 (9

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

    OpenAIRE

    Pinak M. Sanchaniya; Falgun A. Mehta; Uchadadiya, Nirav B.

    2013-01-01

    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 stati...

  7. Screening and identification of multiple components in Tanreqing injection using RP-HPLC combined with DAD and ESI-TOF/MS.

    Science.gov (United States)

    Liu, Shao-Yong; Xue, Dong-Sheng; Pan, Jian-Chao; Zhang, Wen-Ming; Li, Wen-Long; Qu, Hai-Bin

    2014-07-01

    A liquid chromatography coupled with diode array detector (DAD) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) method was developed for the screening and identification of the multiple components in Tanreqing injection, a well-known Chinese medicine injection in China. By combining the DAD spectrum and the accurate mass measurement of ESI-TOF/MS, twelve components in Tanreqing injection were identified. This study contributes to clarifying the nature of Tanreqing injection, and provides an effective and reliable process for the comprehensive and systematic characterization of complex traditional Chinese medicine preparations.

  8. Determination of clenbuterol in porcine tissues using solid-phase extraction combined with ultrasound-assisted dispersive liquid-liquid microextraction and HPLC-UV detection.

    Science.gov (United States)

    Liu, Baomi; Yan, Hongyuan; Qiao, Fengxia; Geng, Yuru

    2011-01-01

    A new pretreatment method, solid-phase extraction combined with dispersive liquid-liquid microextration (SPE-DLLME), was proposed in first time for the determination of clenbuterol (CLB) in porcine tissue samples. The tissue samples were firstly extracted by SPE, then its eluents were used as dispersant of the followed DLLME for further purification and enrichment of CLB. Various parameters (such as the type of SPE sorbent, the type and volume of elution solvent, the type and volume of extractant and dispersant, etc.) that affected the efficiency of the two steps were optimized. Good linearity of CLB was ranged from 0.19 μg/kg to 192 μg/kg with correlation coefficient (r²) of 0.9995. The limit of detection (LOD) was 0.07 μg/kg (S/N=3) and the recoveries at three spiked levels were ranged from 87.9% to 103.6% with the relative standard deviation (RSD) less than 3.9% (n=3). Under the optimized conditions, the enrichment factor (EF) for CLB could up to 62 folds. The presented method that combined the advantages of SPE and DLLME, had higher selectivity than SPE method and was successfully applied to the determination of CLB in tissue samples.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Novel Agent Based-approach for Industrial Diagnosis: A Combined use Between Case-based Reasoning and Similarity Measure

    Directory of Open Access Journals (Sweden)

    Fatima Zohra Benkaddour

    2016-12-01

    Full Text Available In spunlace nonwovens industry, the maintenance task is very complex, it requires experts and operators collaboration. In this paper, we propose a new approach integrating an agent- based modelling with case-based reasoning that utilizes similarity measures and preferences module. The main purpose of our study is to compare and evaluate the most suitable similarity measure for our case. Furthermore, operators that are usually geographically dispersed, have to collaborate and negotiate to achieve mutual agreements, especially when their proposals (diagnosis lead to a conflicting situation. The experimentation shows that the suggested agent-based approach is very interesting and efficient for operators and experts who collaborate in INOTIS enterprise.

  19. Determination of Free Choline in Citicoline Sodium Injection by HPLC with Electrochemical Detection Combined with a Post-Column Immobilized Enzyme Reactor%HPLC-电化学法测定胞磷胆碱钠注射液中游离胆碱含量

    Institute of Scientific and Technical Information of China (English)

    黄晓舞; 刘俊; 徐江; 沈娟

    2012-01-01

    目的 建立胞磷胆碱钠注射液中游离胆碱含量测定方法.方法 采用高效液相色谱电化学检测法,专用色谱柱(ESA ACH-3,250 mm×3 mm ID)和固相胆碱氧化酶反应器(ESA ACH-SPR,3 cm),M5040分析电极和5300型电化学检测器,柱温:35C,流速:0.35 m-1 ·min-1.结果 游离胆碱在0.12 ~2.89 μg.ml-1范围内呈良好线性关系,r=0.9999,平均回收率为100.0%,RSD为2.7%(n=6).结论 该方法简便可行,重复性好,可用于胞磷胆碱钠注射剂中游离胆碱含量测定.%Objective To determine free choline in citicoline sodium injection. Methods HPLC was used together with electrochemical detection combined with a post-column immobilized enzyme reactor (IMER). This assay was based on the separation of choline on a polymer gel column(ESA ACH-3,250 mm×3 mm ID) followed by the passage of the effluent through an IMER (ESA ACH-SPR,3 cm) ,on which the separated choline reacted respectively to give each stoichiometric yield of hydrogen peroxide, which was detected electrochemically at an electrode ( ESA M5040, E1: + 300 mV). The flow rate was 0. 35 ml·min-1 ,and the column temperature was 35℃. Results The linear range of free choline was 0. 12-2. 89 μg·ml-1 ( r =0. 9999) ,The average recovery was 100. 0% and RSD was 1.6%. Conclusion This method can be used for quality control of free choline in citicoline sodium injection.

  20. 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

  1. 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.

  2. 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

  3. Determination of three kinds of fluorescent whitening agents in disposable cups and containers by HPLC with fluorescence detector%高效液相色谱-荧光法测定一次性纸杯和餐盒中3种荧光增白剂的含量

    Institute of Scientific and Technical Information of China (English)

    孟怀山; 李雪莉; 张盼盼; 冉文生; 姚军

    2015-01-01

    A method for the determination of fluorescent whitening agents in disposable cups and contain-ers by high performance liquid chromatography ( HPLC) with fluorescence detector was developed. The HPLC method was performed on a column of Inertsil ODS-3(250 mm × 4. 6 mm,5 μm) by gradient elu-tion using 5 mmol/L ammonium acetate and acetonitrile as the mobile phases with a flow rate of 0. 5 mL/min,and detected by the fluorescence detector at an excitation wavelength of 350 nm and an emission wavelength of 430 nm. Results showed that the three fluorescent whitening agents( B2729,220, B2730) were separated well. The recovery were 77. 4% ~94. 6%,good linearities with RSD were not more than 10%. The method is simple,accurate,sensitive and can meet the requirements of the determi-nation of fluorescent whitening agents in disposable cups and containers.%建立测定一次性纸杯和餐盒中荧光增白剂含量的高效液相色谱-荧光方法。采用Inertsil ODS-3(250 mm ×4.6 mm,5μm)为分析柱,以5 mmol/L乙酸铵溶液和乙腈为流动相,梯度洗脱,流速为0.5 mL/min,荧光激发波长为350 nm,发射波长为430 nm。结果表明,所选用的3种荧光增白剂(B2729、220、B2730)可以较好地被分离,回收率为77.4%~94.6%,相对标准偏差<10%且线性关系良好。该法简便快捷、结果准确、灵敏度高,能够满足对一次性纸杯和餐盒中荧光增白剂含量的检测。

  4. Therapeutic potential and critical analysis of trastuzumab and bevacizumab in combination with different chemotherapeutic agents against metastatic breast/colorectal cancer affecting various endpoints.

    Science.gov (United States)

    Wahid, Mohd; Mandal, Raju K; Dar, Sajad A; Jawed, Arshad; Lohani, Mohtashim; Areeshi, Mohammad Y; Akhter, Naseem; Haque, Shafiul

    2016-08-01

    Researchers are working day and night across the globe to eradicate or at least lessen the menace of cancer faced by the mankind. The two very frequently occurring cancers faced by the human beings are metastatic breast cancer and metastatic colorectal cancer. The various chemotherapeutic agents like anthracycline, cyclophosphamide, paclitaxel, irinotecan, fluorouracil and leucovorin etc., have been used impressively for long. But the obstinate character of metastatic breast cancer and metastatic colorectal cancer needs more to tackle the threat. So, the scientists found the use of monoclonal antibodies trastuzumab (Herceptin(®)) and bevacizumab (Avastin(®)) for the same. The current study critically investigates the therapeutic potential of trastuzumab and bevacizumab in combination with various chemotherapeutic agents against metastatic breast cancer and metastatic colorectal cancer. To the best of our knowledge, this is the very first critical analysis showing percent wise increase in various positive endpoints like median time to disease progression, median survival, and progression free survival etc. for the treatment of metastatic breast/colorectal cancer using trastuzumab and bevacizumab in combination with different chemotherapeutic agents and provides the rational for the success and failure of the selected monoclonal antibodies.

  5. Theoretical modeling suggests that synergy may result from combined use of two biocontrol agents for controlling foliar pathogens under spatial heterogeneous conditions.

    Science.gov (United States)

    Xu, X-M; Jeger, M J

    2013-08-01

    There has been a trend for combined use of several biocontrol agents (BCAs) with an expectation of synergistic interactions among BCAs. However, previous modeling studies suggested that, under homogeneous and temporal-fluctuating conditions, combined use of two BCAs, in most cases, only results in efficacies similar to the more efficacious one used alone; a result consistent with published experimental data. The present modeling study investigated whether combined use of two mycoparasitic BCAs, two competitive BCAs, or a mycoparasitic and a competitive BCA leads to synergistic interactions under spatially heterogeneous conditions. In the model, there were two patches with varying relative sizes and two BCAs differentially adapted to the two patches. Within the range of model parameter values considered, combined use of two BCAs is more effective than the more efficacious BCA used alone in 72% of the simulated cases. There was also a considerable proportion (≈21%) of model simulations in which combined use of two BCAs led to synergy (i.e., efficacy was greater than expected under the assumption of Bliss independence, especially when each of the two BCAs can only survive in one [different] patch). Combined use of a mycoparasitic BCA with a competitive one is more likely to result in synergy than the other two BCA combinations. When biocontrol activities of individual BCAs are low or moderate, biocontrol efficacy arising from combined use of two BCAs does not depend greatly on biocontrol mechanisms. However, for high BCA activities, combined use with at least one competitive BCA resulted in better control than combined use of two mycoparasitic BCAs. The present modeling study emphasized the need for understanding the degree of spatial patchiness and quantitative relationships between biocontrol activities and external conditions in order to apply commercial BCAs effectively.

  6. 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

  7. 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)

  8. Enhanced bioavailability of a poorly water-soluble weakly basic compound using a combination approach of solubilization agents and precipitation inhibitors: a case study.

    Science.gov (United States)

    Li, Shu; Pollock-Dove, Crystal; Dong, Liang C; Chen, Jing; Creasey, Abla A; Dai, Wei-Guo

    2012-05-07

    Poorly water-soluble weakly basic compounds which are solubilized in gastric fluid are likely to precipitate after the solution empties from the stomach into the small intestine, leading to a low oral bioavailability. In this study, we reported an approach of combining solubilization agents and precipitation inhibitors to produce a supersaturated drug concentration and to prolong such a drug concentration for an extended period of time for an optimal absorption, thereby improving oral bioavailability of poorly water-soluble drugs. A weakly basic compound from Johnson and Johnson Pharmaceutical Research and Development was used as a model compound. A parallel microscreening precipitation method using 96-well plates and a TECAN robot was used to assess the precipitation of the tested compound in the simulated gastric fluid (SGF) and the simulated intestinal fluid (SIF), respectively, for lead solubilizing agents and precipitation inhibitors. The precipitation screening results showed vitamin E TPGS was an effective solubilizing agent and Pluronic F127 was a potent precipitation inhibitor for the tested compound. Interestingly, the combination of Pluronic F127 with vitamin E TPGS resulted in a synergistic effect in prolonging compound concentration upon dilution in SIF. In addition, HPMC E5 and Eudragit L100-55 were found to be effective precipitation inhibitors for the tested compounds in SGF. Furthermore, optimization DOE study results suggested a formulation sweet spot comprising HPMC, Eudragit L 100-55, vitamin E TPGS, and Pluronic F127. The lead formulation maintained the tested compound concentration at 300 μg/mL upon dilution in SIF, and more than 70% of the compound remained solubilized compared with the compound alone at <1 μg/mL of its concentration. Dosing of the solid dosage form predissolved in SGF in dogs resulted in 52% of oral bioavailability compared to 26% for the suspension control, a statistically significant increase (p = 0.002). The enhanced

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Combination use of medicines from two classes of renin–angiotensin system blocking agents: risk of hyperkalemia, hypotension, and impaired renal function

    Science.gov (United States)

    Esteras, Raquel; Perez-Gomez, Maria Vanessa; Rodriguez-Osorio, Laura; Ortiz, Alberto

    2015-01-01

    European and United States regulatory agencies recently issued warnings against the use of dual renin–angiotensin system (RAS) blockade therapy through the combined use of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs) or aliskiren in any patient, based on absence of benefit for most patients and increased risk of hyperkalemia, hypotension, and renal failure. Special emphasis was made not to use these combinations in patients with diabetic nephropathy. The door was left open to therapy individualization, especially for patients with heart failure, when the combined use of an ARB and ACEI is considered absolutely essential, although renal function, electrolytes and blood pressure should be closely monitored. Mineralocorticoid receptor antagonists were not affected by this warning despite increased risk of hyperkalemia. We now critically review the risks associated with dual RAS blockade and answer the following questions: What safety issues are associated with dual RAS blockade? Can the safety record of dual RAS blockade be improved? Is it worth trying to improve the safety record of dual RAS blockade based on the potential benefits of the combination? Is dual RAS blockade dead? What is the role of mineralocorticoid antagonists in combination with other RAS blocking agents: RAAS blockade? PMID:26301070

  14. Combination use of medicines from two classes of renin-angiotensin system blocking agents: risk of hyperkalemia, hypotension, and impaired renal function.

    Science.gov (United States)

    Esteras, Raquel; Perez-Gomez, Maria Vanessa; Rodriguez-Osorio, Laura; Ortiz, Alberto; Fernandez-Fernandez, Beatriz

    2015-08-01

    European and United States regulatory agencies recently issued warnings against the use of dual renin-angiotensin system (RAS) blockade therapy through the combined use of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs) or aliskiren in any patient, based on absence of benefit for most patients and increased risk of hyperkalemia, hypotension, and renal failure. Special emphasis was made not to use these combinations in patients with diabetic nephropathy. The door was left open to therapy individualization, especially for patients with heart failure, when the combined use of an ARB and ACEI is considered absolutely essential, although renal function, electrolytes and blood pressure should be closely monitored. Mineralocorticoid receptor antagonists were not affected by this warning despite increased risk of hyperkalemia. We now critically review the risks associated with dual RAS blockade and answer the following questions: What safety issues are associated with dual RAS blockade? Can the safety record of dual RAS blockade be improved? Is it worth trying to improve the safety record of dual RAS blockade based on the potential benefits of the combination? Is dual RAS blockade dead? What is the role of mineralocorticoid antagonists in combination with other RAS blocking agents: RAAS blockade?

  15. 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

  16. The relevance of the pharmacologic properties of a progestational agent to its clinical effects as a combination oral contraceptive.

    OpenAIRE

    Upton, G. V.; Corbin, A

    1989-01-01

    Levonorgestrel (LNg) is known for its marked progestational/contraceptive activity. As shown in animal experiments, however, high doses of LNg are required to elicit an androgenic response; in contrast, considerably lower doses of LNg are required for antiovulatory (contraceptive) action. Thus, a large dose separation exists between androgenic and contraceptive activity. When LNg is combined with an estrogen, as in the contraceptive formulations, the androgenic response is attenuated or negat...

  17. 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

    (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...

  18. 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

  19. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-04-01

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

  1. 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.

  2. 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

  3. Efficacy of dietary antioxidants combined with a chemotherapeutic agent on human colon cancer progression in a fluorescent orthotopic mouse model.

    Science.gov (United States)

    Ma, Huaiyu; Das, Tapas; Pereira, Suzette; Yang, Zhijian; Zhao, Ming; Mukerji, Pradip; Hoffman, Robert M

    2009-07-01

    We report here the efficacy of dietary antioxidants in combination with chemotherapy on tumor growth in the orthotopic COLO-205-green fluorescent protein (GFP) human colon cancer mouse model. The orthotopically-transplanted nude mice used for the study were randomly divided into 5 groups (A-E) after surgical orthotopic implantation (SOI) of tumor tissue. The following diets were given: Diet A, modified AIN-93M mature rodent diet with 4% fish oil; Diet B, modified AIN-93M which contains added antioxidants vitamin A, vitamin E, and selenium at levels present in the standard AIN-93M diet; Diet C, Diet A without added antioxidants vitamin A, vitamin E, or selenium; Diet D, Diet A with 5 times the amount of added antioxidants vitamin A, vitamin E, and selenium present in Diet B. Cisplatin, 7 mg/kg, was administered intraperitoneally on day 16 after SOI. Throughout the course of treatment, noninvasive whole-body imaging, based on the GFP expression of the tumor, permitted visualization of tumor progression. At sacrifice, the mean tumor weights showed significant statistical differences in all of the treated groups compared to the negative control (no cisplatin treatment) (p cisplatin efficacy by high-dose antioxidants in combination with fish oil for colon cancer progression and suggests the design of clinical trials for this regimen.

  4. 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.

  5. Enhanced antitumor efficacy of a vascular disrupting agent combined with an antiangiogenic in a rat liver tumor model evaluated by multiparametric MRI.

    Directory of Open Access Journals (Sweden)

    Feng Chen

    Full Text Available A key problem in solid tumor therapy is tumor regrowth from a residual viable rim after treatment with a vascular disrupting agent (VDA. As a potential solution, we studied a combined treatment of a VDA and antiangiogenic. This study was approved by the institutional ethical committee for the use and care of laboratory animals. Rats with implanted liver tumors were randomized into four treatment groups: 1 Zd6126 (Zd; 2 Thalidomide (Tha; 3 Zd in combination with Tha (ZdTha; and 4 controls. Multiparametric MRIs were performed and quantified before and after treatment. Circulating endothelial progenitor cells (EPCs and plasma stromal cell-derived factor-1α (SDF-1α were monitored. Tumor apoptosis, necrosis, and microvessels were verified by histopathology. A single use of Zd or Tha did not significantly delay tumor growth. The combined ZdTha showed enhanced antitumor efficacy due to synergistic effects; it induced a cumulative tumor apoptosis or necrosis, which resulted in significant delay in tumor growth and reduction in the viable tumor rim; it also reduced tumor vessel permeability; and it improved tumor hemodynamic indexes, most likely via a transient normalization of tumor vasculature induced by Tha. A stepwise linear regression analysis showed that the apparent diffusion coefficient was an independent predictor of tumor growth. We found no significant increases in Zd-induced circulating EPCs or plasma SDF-1α. ZdTha showed improved therapeutic efficacy in solid tumors compared to either agent alone. The therapeutic effects were successfully tracked in vivo with multiparametric MRI.

  6. Quantitative EEG and Current Source Density Analysis of Combined Antiepileptic Drugs and Dopaminergic Agents in Genetic Epilepsy: Two Case Studies.

    Science.gov (United States)

    Emory, Hamlin; Wells, Christopher; Mizrahi, Neptune

    2015-07-01

    Two adolescent females with absence epilepsy were classified, one as attention deficit and the other as bipolar disorder. Physical and cognitive exams identified hypotension, bradycardia, and cognitive dysfunction. Their initial electroencephalograms (EEGs) were considered slightly slow, but within normal limits. Quantitative EEG (QEEG) data included relative theta excess and low alpha mean frequencies. A combined treatment of antiepileptic drugs with a catecholamine agonist/reuptake inhibitor was sequentially used. Both patients' physical and cognitive functions improved and they have remained seizure free. The clinical outcomes were correlated with statistically significant changes in QEEG measures toward normal Z-scores in both anterior and posterior regions. In addition, low resolution electromagnetic tomography (LORETA) Z-scored source correlation analyses of the initial and treated QEEG data showed normalized patterns, supporting a neuroanatomic resolution. This study presents preliminary evidence for a neurophysiologic approach to patients with absence epilepsy and comorbid disorders and may provide a method for further research.

  7. 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)

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. HPLC-PDA指纹图谱结合主成分分析评价不同产地冬凌草药材的质量%Quality evaluation of Rabdosiae Rubescentis Herba from different areas by HPLC-PDA fingerprint combined with principle component analysis

    Institute of Scientific and Technical Information of China (English)

    靳怡然; 杜英峰; 田婷婷; 马英华; 刘彭玮; 许慧君; 张兰桐

    2015-01-01

    目的 研究并建立不同产地冬凌草药材的HPLC-PDA指纹图谱,并结合主成分分析法(PCA)评价不同产地的冬凌草药材质量,为科学评价与有效控制冬凌草药材质量提供可靠的方法.方法 采用HPLC-PDA法构建冬凌草药材的指纹图谱,同时应用PCA和相似度分析法对实验数据进行处理,以找出4个不同产地18批冬凌草样品间的相似性及差异性.色谱柱为DiamonsilTMC18柱(250mm×4.6 mm,5μm),柱温为30℃;检测波长为238nm,流动相为乙腈-0.05%磷酸水进行梯度洗脱,体积流量0.8mL/min.结果 标定了冬凌草药材HPLC指纹图谱的19个共有峰,并指认了其中的4个共有峰,分别为冬凌草甲素、冬凌草乙素、拉西多宁和迷迭香酸,18批冬凌草药材的相似度为0.421~0.984.PCA结果表明,前3个因子的累积贡献率达到87.3%,选择这3个因子对冬凌草药材进行综合评价.结论 HPLC指纹图谱结合PCA可以快速、客观地评价冬凌草药材的质量差异.

  13. HPLC profiling of Phellinus linteus.

    Science.gov (United States)

    Kojima, Kazuo; Ogihara, Yukio; Sakai, Yoshimichi; Mizukami, Hajime; Nagatsu, Akito

    2008-10-01

    HPLC chromatograms of MeOH extracts from a fruit body of the wild-grown P. linteus (natural fruit body), from cultivated fungus (cultivated fruit body), and from the cultured mycelia were compared. The extract prepared from the natural fruit bodies revealed a typical HPLC profile referred to as type 1 with a major peak corresponding to meshimakobnol A (1) together with two minor peaks of hypholomine B (3) and inoscavin A (4); the cultivated fruit bodies exhibited a profile referred to as type 2 with major peaks corresponding to 3 and 4 and a minor peak of 1, and the cultured mycelia showed a profile referred to as type 3 without any of these peaks. We also analyzed HPLC chromatograms of commercial products of P. linteus obtained in the markets. Most of the products claimed to be natural fruit bodies exhibited type 1 profiles, except for one product having an intermediate HPLC profile between type 1 and type 2. The products claimed to be cultivated fruit bodies and cultured mycelia revealed type 2 and type 3 profiles, respectively. The present results indicate that the HPLC chromatogram of the methanol extract of P. linteus can be used as a fingerprint to identify whether the product is from natural fruit bodies, cultivated fruit bodies, or cultured mycelia.

  14. 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

  15. Evolution of systemic treatment for hormone-sensitive breast cancer: from sequential use of single agents to the upfront administration of drug combinations

    Directory of Open Access Journals (Sweden)

    E. N. Imyanitov

    2016-01-01

    Full Text Available Current standards of treatment of endocrine-dependent cancers (breast cancer (BC, prostate cancer imply sequential use of endocrine therapy and cytotoxic agents: it is believed, that steroid hormone antagonists cease the division of transformed cells and therefore make them resistant to other therapeutic modalities. It is important to recognize that conceptual investigations in this field were carried out dozens of years ago, and often involved relatively non-efficient drugs, imperfect laboratory tests, etc. There are several recent examples of combined use of endocrine therapy and other compounds. The addition of docetaxel (6 cycles to androgen deprivation resulted in significant improvement of overall survival in men with metastatic prostate cancer. Clinical trial involving the combined use of exemestane and everolimus demonstrated promising results. There are ongoing studies on inhibitors of cycline-dependent kinases. Use of these drugs in the beginning of endocrine therapy may significantly delay resistance to the antagonists of estrogen signaling.

  16. 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.

  17. Fast and environmentally friendly quantitative analysis of active agents in anti-diabetic tablets by an alternative laser-induced breakdown spectroscopy (LIBS) method and comparison to a validated reversed-phase high-performance liquid chromatography (RP-HPLC) method.

    Science.gov (United States)

    Contreras, Victor Ulises; Meneses-Nava, Marco A; Ornelas-Soto, Nancy; Barbosa-García, Oracio; López-de-Alba, Pedro L; Maldonado, José L; Ramos-Ortiz, Gabriel; Acevedo-Aguilar, Francisco J; López-Martínez, Leticia

    2012-11-01

    Laser-induced breakdown spectroscopy (LIBS) is evaluated as a potential analytic technique for rapid screening and quality control of anti-diabetic tablets. This paper proposes a simple LIBS-based method for the quantitative analysis of two active pharmaceutical ingredients (APIs): metformin (Met) and glybenclamide (Gly). In order to quantify both APIs, chlorine (Cl) concentration was estimated by employing the Cl/Br optical emission ratio, where Br was introduced as internal standard. Calibration curves were prepared, achieving linearity higher than 99%. On the other hand, for comparison to the proposed method, an isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method was also developed for quantitative determination of the same analytes by ultraviolet (UV) detection. The chromatographic separation was achieved on a Phenomenex Hypersil C18, 250 mm × 4.6 mm, 5 μm column. The mobile phase was K(2)HPO(4)/H(3)PO(4)-CH(3)OH and flow rate was 1.0 mL min(-1). The method is linear over a range of 10-60 μg mL(-1) for Gly and 5-30 μg mL(-1) for Met and the correlation coefficients were ≥0.99. Recoveries were found to be in the range of 95-101%. Furthermore, four different commercial brands of each active agent were evaluated by both proposed LIBS and chromatographic methods and results were compared with each other. The comparison was satisfactorily validated by analysis of variance (ANOVA).

  18. 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.

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

    Science.gov (United States)

    Maulina, Dina; Anggraeni, Tjandra

    2014-03-01

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

  20. 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.

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    Xue C

    2016-03-01

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

  3. 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.

  4. The combined bacterial Lux-Fluoro test for the detection and quantification of genotoxic and cytotoxic agents in surface water: results from the "Technical Workshop on Genotoxicity Biosensing".

    Science.gov (United States)

    Baumstark-Khan, Christa; Rabbow, Elke; Rettberg, Petra; Horneck, Gerda

    2007-12-15

    The bioassay Lux-Fluoro test was developed for the rapid detection and quantification of environmental pollutants with genotoxic and/or cytotoxic potential. This bacterial test system uses two different reporter genes whose gene products and their reactions, respectively, can be measured easily and simultaneously by optical methods. Genotoxicity is measured by the increase of bioluminescence in genetically modified bacteria which carry a plasmid with a complete lux operon for the enzyme luciferase from the marine photobacterium P. leiognathi under the control of a DNA-damage dependent so-called SOS promoter. If the deoxyribonucleic acid in these bacteria is damaged by a genotoxic chemical, the SOS promoter is turned on and the lux operon is expressed. The newly synthesized luciferase reacts immediately with its substrate thereby producing bioluminescence in a damage-proportional manner. In the second part of the system, genetically modified bacteria carry the gene for the green fluorescent protein (gfp) from the jellyfish Aequora victoria downstream from a constitutively expressed promoter. These bacteria are fluorescent under common growth conditions. If their cellular metabolism is disturbed by the action of cytotoxic chemicals, the fluorescence decreases in a dose-proportional manner. The combined Lux-Fluoro test is shown to be well suited for the biological assessment of the geno- and cytotoxicity of a series of model agents and environmental samples at the Technical Workshop on Genotoxicity Biosensing (TECHNOTOX).

  5. 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.)

  6. 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.

  7. 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.

  8. Combined resection and multi-agent adjuvant chemotherapy for desmoplastic small round cell tumor arising in the abdominal cavity: Report of a case

    Institute of Scientific and Technical Information of China (English)

    Chang-Cheng Chang; Jun-Te Hsu; Jeng-Hwei Tseng; Tsann-Long Hwang; Han-Ming Chen; Yi-Yin Jan

    2006-01-01

    Desmoplastic small round cell tumor (DSRCT) is a rare,highly aggressive malignancy with distinctive histological features: a nesting pattern of cellular growth within dense desmoplastic stroma, occurring in young population with male predominance. The mean survival period is only about 1.5-2.5 years. The tumor has co-expressed epithelial, muscle, and neural markers in immunohistochemical studies. This work reports a 27-year-old man presenting with hematemesis and chronic constipation.Serial studies including endoscopy, upper gastrointestinal series, abdominal computed tomography and barium enema study showed disseminated involvement of visceral organs. The patient underwent aggressive surgery and received postoperative adjuvant chemotherapy consisting of 5-fluorouracil, cyclophosphamide,etoposide, doxorubicin, and cisplatin. He survived without any disease for 20 mo after the surgery. No standard treatment protocol has been established. Aggressive surgery combined with postoperative multi-agent adjuvant chemotherapy is justified not only to relieve symptoms but also to try to improve the outcome in this advanced DSRCT young patient.

  9. 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。

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

    Science.gov (United States)

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

    2016-05-01

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

  11. 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

  12. 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.

  13. Preparative chromatographic resolution of racemates using HPLC and SFC in a pharmaceutical discovery environment.

    Science.gov (United States)

    Miller, Larry; Potter, Matt

    2008-11-01

    The preparative chromatographic resolution of racemates has become a standard approach for the generation of enantiomers in pharmaceutical discovery laboratories. This paper will discuss the use of preparative HPLC and SFC to generate individual enantiomers for discovery activities. Analytical HPLC and SFC method development to rapidly screen chiral stationary phases and solvent combinations will be presented. The usefulness of preparative chromatographic resolution of racemates will be demonstrated through the presentation of numerous non-routine case studies from the laboratories at Amgen.

  14. 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

    DEFF Research Database (Denmark)

    Liu, Bingrui; Kongstad, Kenneth Thermann; Wiese, Stefanie;

    2016-01-01

    a Trolox equivalent antioxidant capacity of 135 and 108 mM Trolox mg−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......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...

  15. 低氧富氮结合脱氧剂储粮技术探索%Exploration of Grain Storage Technology Using Deoxidizing Agent Combined with Low Oxygen Nitrogen-rich

    Institute of Scientific and Technical Information of China (English)

    常亚飞; 孙俊; 陈彩根

    2014-01-01

    通过对不同粮堆分别进行低氧富氮、脱氧剂结合低氧富氮、脱氧剂等储藏效果的对比,脱氧剂结合低氧富氮技术相对于单独使用脱氧剂和低氧富氮更加经济有效。%For different grain piles, we use the different storage methods such as using low oxygen nitrogen-rich, deoxidizing agent combined with low oxygen nitrogen-rich and deoxidizer, the results show, deoxidizing agent combined with low oxygen nitrogen-rich storage technology is more effectively and economically than the storage technology using deoxidizers and low oxygen nitrogen-rich.

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

    Science.gov (United States)

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

    2016-01-01

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

  17. Antimycobacterial agents differ with respect to their bacteriostatic versus bactericidal activities in relation to time of exposure, mycobacterial growth phase, and their use in combination.

    NARCIS (Netherlands)

    I.A.J.M. Bakker-Woudenberg (Irma); W. van Vianen (Wim); D. van Soolingen (Dick); H.A. Verbrugh (Henri); M.A. Agtmael (Michiel)

    2005-01-01

    textabstractA number of antimycobacterial agents were evaluated with respect to their bacteriostatic activity (growth inhibition) versus the bactericidal activity against a clinical isolate of Mycobacterium avium (Mycobacterium avium complex [MAC] strain 101) in relation to the time of exposure and

  18. 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.

  19. 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.

  20. 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...

  1. Combining exploratory scenarios and participatory backcasting: using an agent-based model in participatory policy design for a multi-functional landscape.

    Science.gov (United States)

    Van Berkel, Derek B; Verburg, Peter H

    While the merits of local participatory policy design are widely recognised, limited use is made of model-based scenario results to inform such stakeholder involvement. In this paper we present the findings of a study using an agent based model to help stakeholders consider, discuss and incorporate spatial and temporal processes in a backcasting exercise for rural development. The study is carried out in the Dutch region called the Achterhoek. Region-specific scenarios were constructed based on interviews with local experts. The scenarios are simulated in an agent based model incorporating rural residents and farmer characteristics, the environment and different policy interventions for realistic projection of landscape evolution. Results of the model simulations were presented to stakeholders representing different rural sectors at a workshop. The results indicate that illustration of the spatial configuration of landscape changes is appreciated by stakeholders. Testing stakeholders' solutions by way of model simulations revealed that the effectiveness of local interventions is strongly related to exogenous processes such as market competition and endogenous processes like local willingness to engage in multifunctional activities. The integration of multi-agent modelling and participatory backcasting is effective as it offers a possibility to initiate discussion between experts and stakeholders bringing together different expertise.

  2. 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.

  3. 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.

  4. Multifunctional Poly(L-lactide)-Polyethylene Glycol-Grafted Graphene Quantum Dots for Intracellular MicroRNA Imaging and Combined Specific-Gene-Targeting Agents Delivery for Improved Therapeutics.

    Science.gov (United States)

    Dong, Haifeng; Dai, Wenhao; Ju, Huangxian; Lu, Huiting; Wang, Shiyan; Xu, Liping; Zhou, Shu-Feng; Zhang, Yue; Zhang, Xueji

    2015-05-27

    Photoluminescent (PL) graphene quantum dots (GQDs) with large surface area and superior mechanical flexibility exhibit fascinating optical and electronic properties and possess great promising applications in biomedical engineering. Here, a multifunctional nanocomposite of poly(l-lactide) (PLA) and polyethylene glycol (PEG)-grafted GQDs (f-GQDs) was proposed for simultaneous intracellular microRNAs (miRNAs) imaging analysis and combined gene delivery for enhanced therapeutic efficiency. The functionalization of GQDs with PEG and PLA imparts the nanocomposite with super physiological stability and stable photoluminescence over a broad pH range, which is vital for cell imaging. Cell experiments demonstrate the f-GQDs excellent biocompatibility, lower cytotoxicity, and protective properties. Using the HeLa cell as a model, we found the f-GQDs effectively delivered a miRNA probe for intracellular miRNA imaging analysis and regulation. Notably, the large surface of GQDs was capable of simultaneous adsorption of agents targeting miRNA-21 and survivin, respectively. The combined conjugation of miRNA-21-targeting and survivin-targeting agents induced better inhibition of cancer cell growth and more apoptosis of cancer cells, compared with conjugation of agents targeting miRNA-21 or survivin alone. These findings highlight the promise of the highly versatile multifunctional nanocomposite in biomedical application of intracellular molecules analysis and clinical gene therapeutics.

  5. 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.

  6. 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.

  7. HepG2 cells biospecific extraction and HPLC-ESI-MS analysis for screening potential antiatherosclerotic active components in Bupeuri radix.

    Science.gov (United States)

    Liu, Shuqiang; Tan, Zhibin; Li, Pingting; Gao, Xiaoling; Zeng, Yuaner; Wang, Shuling

    2016-03-20

    HepG2 cells biospecific extraction method and high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) analysis was proposed for screening of potential antiatherosclerotic active components in Bupeuri radix, a well-known Traditional Chinese Medicine (TCM). The hypothesis suggested that when cells are incubated together with the extracts of TCM, the potential bioactive components in the TCM should selectively combine with the receptor or channel of HepG2 cells, then the eluate which contained biospecific component binding to HepG2 cells was identified using HPLC-ESI-MS analysis. The potential bioactive components of Bupeuri radix were investigated using the proposed approach. Five compounds in the saikosaponins of Bupeuri radix were detected as these components selectively combined with HepG2 cells, among these compounds, two potentially bioactive compounds namely saikosaponin b1 and saikosaponin b2 (SSb2) were identified by comparing with the chromatography of the standard sample and analysis of the structural clearance characterization of MS. Then SSb2 was used to assess the uptake of DiI-high density lipoprotein (HDL) in HepG2 cells for antiatherosclerotic activity. The results have showed that SSb2, with indicated concentrations (5, 15, 25, and 40 μM) could remarkably uptake dioctadecylindocarbocyanine labeled- (DiI) -HDL in HepG2 cells (Vs control group, *Pcomponents in TCM and SSb2 may be a valuable novel drug agent for the treatment of atherosclerosis.

  8. 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.

  9. An In-Depth Comparison of Latency-Reversing Agent Combinations in Various In Vitro and Ex Vivo HIV-1 Latency Models Identified Bryostatin-1+JQ1 and Ingenol-B+JQ1 to Potently Reactivate Viral Gene Expression.

    Directory of Open Access Journals (Sweden)

    Gilles Darcis

    2015-07-01

    Full Text Available The persistence of latently infected cells in patients under combinatory antiretroviral therapy (cART is a major hurdle to HIV-1 eradication. Strategies to purge these reservoirs are needed and activation of viral gene expression in latently infected cells is one promising strategy. Bromodomain and Extraterminal (BET bromodomain inhibitors (BETi are compounds able to reactivate latent proviruses in a positive transcription elongation factor b (P-TEFb-dependent manner. In this study, we tested the reactivation potential of protein kinase C (PKC agonists (prostratin, bryostatin-1 and ingenol-B, which are known to activate NF-κB signaling pathway as well as P-TEFb, used alone or in combination with P-TEFb-releasing agents (HMBA and BETi (JQ1, I-BET, I-BET151. Using in vitro HIV-1 post-integration latency model cell lines of T-lymphoid and myeloid lineages, we demonstrated that PKC agonists and P-TEFb-releasing agents alone acted as potent latency-reversing agents (LRAs and that their combinations led to synergistic activation of HIV-1 expression at the viral mRNA and protein levels. Mechanistically, combined treatments led to higher activations of P-TEFb and NF-κB than the corresponding individual drug treatments. Importantly, we observed in ex vivo cultures of CD8+-depleted PBMCs from 35 cART-treated HIV-1+ aviremic patients that the percentage of reactivated cultures following combinatory bryostatin-1+JQ1 treatment was identical to the percentage observed with anti-CD3+anti-CD28 antibodies positive control stimulation. Remarkably, in ex vivo cultures of resting CD4+ T cells isolated from 15 HIV-1+ cART-treated aviremic patients, the combinations bryostatin-1+JQ1 and ingenol-B+JQ1 released infectious viruses to levels similar to that obtained with the positive control stimulation. The potent effects of these two combination treatments were already detected 24 hours post-stimulation. These results constitute the first demonstration of LRA

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  12. Probing of the combined effect of bisquaternary ammonium antimicrobial agents and acetylsalicylic acid on model phospholipid membranes: differential scanning calorimetry and mass spectrometry studies.

    Science.gov (United States)

    Kasian, N A; Pashynska, V A; Vashchenko, O V; Krasnikova, A O; Gömöry, A; Kosevich, M V; Lisetski, L N

    2014-12-01

    A model molecular biosystem of hydrated dipalmitoylphosphatidylcholine (DPPC) bilayers that mimics cell biomembranes is used to probe combined membranotropic effects of drugs by instrumental techniques of molecular biophysics. Differential scanning calorimetry reveals that doping of the DPPC model membrane with individual bisquaternary ammonium compounds (BQAC) decamethoxinum, ethonium, thionium and acetylsalicylic acid (ASA) leads to lowering of the membrane melting temperature (Tm) pointing to membrane fluidization. Combined application of the basic BQAC and acidic ASA causes an opposite effect on Tm (increase), corresponding to the membrane densification. Thus, modulation of the membranotropic effects upon combined use of the drugs studied can be revealed at the level of model membranes. Formation of noncovalent supramolecular complexes of the individual BQACs and ASA with DPPC molecules, which may be involved in the mechanism of the drug-membrane interaction at the molecular level, is demonstrated by electrospray ionization (ESI) mass spectrometry. In the ternary (DPPC + ASA + BQAC) model systems, the stable complexes of the BQAC dication with the ASA anion, which may be responsible for modulation of the membranotropic effects of the drugs, were recorded by ESI mass spectrometry. The proposed approach can be further developed for preliminary evaluation of the combined effects of the drugs at the level of model lipid membranes prior to tests on living organisms.

  13. 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.

  14. 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

    for the study. MVLN cells, stably transfected with an estrogen receptor (ER) luciferase reporter vector (ERE-CALUX), were exposed to the reconstituted SPE-HPLC extracts for determination of the integrated estrogenic activity. The effects of PCBs were analyzed by direct in vitro exposure of PCBs (138, 153...... 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...... measured by ERE-CALUX was validated and considered to be a valuable tool to assess the combined ER effect of lipophilic serum POPs where additive/synergistic and agonistic/antagonistic effects are integrated giving an overall estimate of exposure and bioactivity....

  15. 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.

  16. 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。

  17. [Uricosuric agent].

    Science.gov (United States)

    Ohno, Iwao

    2008-04-01

    Urate lowering treatment is indicated in patients with recurrent acute attacks, tophi, gouty arthropathy, radiographic changes of gout, multiple joint involvement, or associated uric acid nephrolithiasis. Uricosuric agents like benzbromarone and probenecid are very useful to treat hyperuricemia as well as allopurinol (xanthine oxidase inhibitor). Uricosuric agents act the urate lowering effect through blocking the URAT1, an urate transporter, in brush border of renal proximal tubular cells. In order to avoid the nephrotoxicity and urolithiasis due to increasing of urinary urate excretion by using uricosuric agents, the proper urinary tract management (enough urine volume and correction of aciduria) should be performed.

  18. 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.

  19. 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.

  20. Green synthesis and antibacterial effects of aqueous colloidal solutions of silver nanoparticles using camomile terpenoids as a combined reducing and capping agent.

    Science.gov (United States)

    Parlinska-Wojtan, Magdalena; Kus-Liskiewicz, Małgorzata; Depciuch, Joanna; Sadik, Omowunmi

    2016-08-01

    Green synthesis method using camomile extract was applied to synthesize silver nanoparticles to tune their antibacterial properties merging the synergistic effect of camomile and Ag. Scanning transmission electron microscopy revealed that camomile extract (CE) consisted of porous globular nanometer sized structures, which were a perfect support for Ag nanoparticles. The Ag nanoparticles synthesized with the camomile extract (AgNPs/CE) of 7 nm average sizes, were uniformly distributed on the CE support, contrary to the pure Ag nanoparticles synthesized with glucose (AgNPs/G), which were over 50 nm in diameter and strongly agglomerated. The energy dispersive X-ray spectroscopy chemical analysis showed that camomile terpenoids act as a capping and reducing agent being adsorbed on the surface of AgNPs/CE enabling their reduction from Ag(+) and preventing them from agglomeration. Fourier transform infrared and ultraviolet-visible spectroscopy measurements confirmed these findings, as the spectra of AgNPs/CE, compared to pure CE, did not contain the 1109 cm(-1) band, corresponding to -C-O groups of terpenoids and the peaks at 280 and 320 nm, respectively. Antibacterial tests using four bacteria strains showed that the AgNPs/CE performed five times better compared to CE AgNPs/G samples, reducing totally all the bacteria in 2 h.

  1. INDUCTION AND MAINTENANCE OF ANAESTHESIA BY TWO DIFFERENT INTRAVENOUS ANALGESIC AND SEDATIVE COMBINATION WITHOUT USE OF VOLATILE AGENTS- A CONTROLLED COMPARATIVE CLINICAL STUDY IN DIABETIC AND HYPERTENSIVE PATIENTS

    Directory of Open Access Journals (Sweden)

    Ajay

    2016-01-01

    Full Text Available BACKGROUND In developing country like India with limited resources we need to find ways and means of cutting the anaesthetic cost without compromising safety of patient. With the availability of various intravenous analgesics and sedatives drugs safe anaesthesia can be delivered without the use of costly volatile agents and vaporisers. METHODS 90 Adult diabetic and/or hypertensive patients were divided into three groups of 30 each. Group I patients received inj. Morphine followed by Midazolam. Group II patients received inj. Diazepam followed by Buprenorphine. Group III patients were induced with inj. Fentanyl followed by Thiopentone sodium while maintenance of anaesthesia was achieved using halothane. Hemodynamic parameters, induction and awakening time, postoperative analgesia, and cost were statistically analyzed. RESULTS Hemodynamic parameters showed no significant fluctuations and stayed within the acceptable sinus range in all three groups. Induction time was short but awakening time was longer in group III as compared to other two groups. Postoperative analgesia was longest in group II and this group was cost effective too.

  2. Antibiotic Agents

    Science.gov (United States)

    ... Superbugs and Drugs" Home | Contact Us General Background: Antibiotic Agents What is an antibacterial and how are ... with the growth and reproduction of bacteria. While antibiotics and antibacterials both attack bacteria, these terms have ...

  3. Vasoactive Agents

    OpenAIRE

    Husedzinovic, Ino; Bradic, Nikola; Goranovic, Tanja

    2006-01-01

    This article is a short review of vasoactive drugs which are in use in todays clinical practice. In the past century, development of vasoactive drugs went through several phases. All of these drugs are today divided into several groups, depending on their place of action, pharmacological pathways and/or effects on target organ or organ system. Hence, many different agents are today in clinical practice, we have shown comparison between them. These agents provide new directions in the treatmen...

  4. Preclinical evaluation of PI3K inhibitor BYL719 as a single agent and its synergism in combination with cisplatin or MEK inhibitor in nasopharyngeal carcinoma (NPC)

    Science.gov (United States)

    Wong, Chi Hang; Ma, Brigette Buig Yue; Cheong, Hio Teng; Hui, Connie Wun Chun; Hui, Edwin Pun; Chan, Anthony Tak Cheung

    2015-01-01

    Nasopharyngeal carcinoma (NPC) is endemic to Southeast Asia and over 40% of NPC tissues harbor PIK3CA amplifications. This study aims to study the preclinical activity of a novel PI3K inhibitor, BYL719, in 6 NPC cell lines: C666-1, CNE-2, HK1, HK1-EBV, HONE-1 and HONE-1-LMP1. Over 70% of growth inhibition was attained when NPC cell lines were exposed to increasing concentrations of BYL719, with IC50 values at the low micro-molar range. Two BYL719-sensitive cell lines that harbor PIK3CA mutations, CNE-2 and HONE-1, were selected for further analysis on the effect of BYL719 on cell cycle progression, apoptosis and PI3K signaling. BYL719 significantly reduced the phosphorylation of Akt, and the Akt-mTOR axis downstream effector S6 in these 2 cell lines, but a feedback activation of MAPK was observed at 72 hours post-treatment. BYL719 induced G0/G1 cell cycle arrest and apoptosis in both cell lines. In 3D cell culture models, the growth of NPC spheroids was significantly inhibited in a dose-depending manner. When BYL719 was combined with a MEK inhibitor (AZD6244) in a 3D cell culture system, strong synergism on NPC cell growth was observed with attenuation of MAPK activation. A synergistic inhibitory effect on growth was observed when BYL719 was combined with higher dose levels of cisplatin. These data suggest that BYL719 has preclinical activity in NPC cell lines especially in those which harbor PIK3CA mutation. Combination with a MEK inhibitor maybe a useful strategy that warrants further investigation. PMID:26101713

  5. 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.

  6. In-vivo luminescence model for the study of tumor regression and regrowth following combination regimens with differentiation-promoting agents and photodynamic therapy

    Science.gov (United States)

    Rollakanti, K.; Anand, S.; Maytin, E. V.

    2013-03-01

    Photodynamic therapy with aminolevulinic acid can be modified by pretreatment regimens with drugs such as 5- Fluorouracil (5-FU) or Vitamin D (calcitriol) that enhance accumulation of protoporphyrin IX (PpIX) within tumor tissue which presumably will enhance the therapeutic response to light. However, histological approaches for monitoring therapeutic responses are poorly suited for studying long term survival because large numbers of mice need to be sacrificed. To address this limitation, a non-invasive model to monitor tumor regression and regrowth has been established. Breast cancer cells, stably transfected with firefly luciferase (MDA-Luc cell line), are implanted orthotopically in nude mice (0.25 - 1 x 106 cells/site), and monitored 0-60 min after s.c. injection of luciferin, with Xenogen in-vivo imaging system. Luminescence is detectable at day 1 post-implantation. Tumors are suitable for experimentation on day 6, when daily injections of pretreatment agents (5-FU, 300 mg/kg; calcitriol, 1 μg/kg) begin. On day 9, ALA (75 mg/kg i.p.) is given for 4 hr, followed by illumination (633 nm, 100 J/cm2). Tumor luminescence post- PDT is monitored daily and compared with caliper measurements. Pretreatments (5-FU, calcitriol) by themselves do not inhibit luciferase expression, and all tumors grow at a similar rate during the pretreatment period. Results from in vivo survival experiments can be correlated to survival responses of MDA-Luc cells grown in monolayer cultures +/- PDT and +/- pretreatments, and additional mechanistic information (e.g. Ki67 and E-cadherin expression) obtained. In summary, this noninvasive model will permit testing of the therapeutic survival advantages of various pretreatments during cPDT.

  7. The effect of increasing the pore size of nanofibrous scaffolds on the osteogenic cell culture using a combination of sacrificial agent electrospinning and ultrasonication.

    Science.gov (United States)

    Aghajanpoor, Mahdiyeh; Hashemi-Najafabadi, Sameereh; Baghaban-Eslaminejad, Mohamadreza; Bagheri, Fatemeh; Mohammad Mousavi, Seyyed; Azam Sayyahpour, Foruogh

    2017-03-03

    One of the major problems associated with the electrospun scaffolds is their small pore size, which limits the cellular infiltration for bone tissue engineering. In this study, the effect of increasing the pore size on cellular infiltration was studied in poly/nanohydroxyapatite electrospun scaffolds, which were modified using ultrasonication, co-electrospinning with poly (ethylene oxide), and a combination of both. Ultrasonic process was optimized by central composite design. The ultrasonic output power and time of the process were considered as the effective parameters. The pore size of the scaffolds was evaluated by scanning electron microscope. The optimum conditions, according to the pore area and mechanical properties of the scaffolds were selected, and finally the groups that had the highest pore size and mechanical strength were selected for the combined method. Increasing the pore size enhanced the cellular proliferation, extension and infiltration, as well as the osteodifferentiation of stem cells. At the optimum condition, the average cellular infiltration was 36.51 µm compared to the control group with no cellular infiltration. In addition, alkaline phosphatase activity and the expression of osteocalcin and collagen I (COL I) were, respectively, 1.86, 2.54, and 2.16 fold compared to the control group on day 14. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2017.

  8. [Inotropic agents].

    Science.gov (United States)

    Sasayama, Shigetake

    2003-05-01

    Depression of myocardial contractility plays an important role in the development of heart failure and many inotropic agents were developed to improve the contractile function of the failing heart. Agents that increase cyclic AMP, either by increasing its synthesis or reducing its degradation, exerted dramatic short-term hemodynamic benefits, but these acute effects were not extrapolated into long-term improvement of the clinical outcome of heart failure patients. Administration of these agents to an energy starved failing heart would be expected to increase myocardial energy use and could accelerate disease progression. The role of digitalis in the management of heart failure has been controversial, however, the recent large scale clinical trial has ironically proved that digoxin reduced the rate of hospitalization both overall and for worsening heart failure. More recently, attention was paid to other inotropic agents that have a complex and diversified mechanism. These agents have some phosphodiesterase-inhibitory action but also possess additional effects, including cytokine inhibitors, immunomodulators, or calcium sensitizers. In the Western Societies these agents were again shown to increase mortality of patients with severe heart failure in a dose dependent manner with the long-term administration. However, it may not be the case in the Japanese population in whom mortality is relatively low. Chronic treatment with inotropic agent may be justified in Japanese, as it allows optimal care in the context of relief of symptoms and an improved quality of life. Therefore, each racial group should obtain specific evidence aimed at developing its own guidelines for therapy rather than translating major guidelines developed for other populations.

  9. 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

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

    Directory of Open Access Journals (Sweden)

    Parul Uppal Malhotra

    2016-01-01

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

  11. Evaluation of the potential of hexamethylenetetramine, compared with tirapazamine, as a combined agent with {gamma}-irradiation and cisplatin treatment in vivo.

    Science.gov (United States)

    Masunaga, S; Tano, K; Watanabe, M; Kashino, G; Suzuki, M; Kinashi, Y; Ono, K; Nakamura, J

    2009-05-01

    The purpose of this investigation was to compare the effect on intratumour quiescent (Q) cells in vivo of hexamethylenetetramine (HMTA) or tirapazamine (TPZ) in combination with gamma-irradiation and cisplatin treatment. Squamous cell carcinoma (SCC) VII tumour-bearing mice were administered 5-bromo-2'-deoxyuridine (BrdU) continuously to label all intratumour proliferating (P) cells. The mice then received HMTA or TPZ intraperitoneally or continuously with or without gamma-irradiation or cisplatin treatment. Other tumour-bearing mice received HMTA or TPZ intraperitoneally immediately after gamma-irradiation. Immediately after gamma-irradiation or cisplatin treatment following HMTA or TPZ, or 24 h after gamma-irradiation followed by HMTA or TPZ, the response of Q cells was assessed in terms of the micronucleus frequency using immunofluorescence staining for BrdU. The response of all tumour cells (P + Q) was determined from the BrdU-non-treated tumours. HMTA was more toxic to the subset of Q cells than to the population of tumour cells as a whole, similar to the findings for TPZ. The radiosensitising effect of HMTA was similar to that of TPZ in both all cells and Q cells. The recovery-inhibiting effect of HMTA was reliable, but not as great as that of TPZ. The cisplatin sensitivity-enhancing effect of HMTA was similar to or slightly greater than that of TPZ. Continuous administration of both HMTA and TPZ resulted in higher radiosensitivity- and cisplatin sensitivity-enhancing effects than did a single i.p. administration. We concluded that, in terms of the total tumour cell killing effect, including killing of Q cells, gamma-irradiation and cisplatin treatment combined with continuous HMTA administration is a promising strategy given that HMTA is used in clinics.

  12. Sunscreening Agents

    Science.gov (United States)

    Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B.R.

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents. PMID:23320122

  13. Comprehensive quality evaluation of Chishao by HPLC

    OpenAIRE

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

    2013-01-01

    Objective: The purpose of this paper is to comprehensively evaluate the quality of Chishao. Methods: In the experiment of this paper, the fingerprint spectrums of Chishao in all locations are established by RP-HPLC and the model of principle component analysis with the RP-HPLC peak areas is established. Results: The quality of Chishao in the northern part of China or that made of Paeonia lactiflora is better than that of these in others or that made of other species. The quality of Chishao co...

  14. 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

  15. 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.

  16. 植物诱导抗病剂组合应用对烟草花叶病的防控效果%Control Effects of Combination of Plant Induced Resistant Agents against Tobacco Mosaic Virus (TMV)

    Institute of Scientific and Technical Information of China (English)

    徐兴阳; 董家红; 端永明; 张廷金; 杨龙祥

    2011-01-01

    [Objective] The paper was explore the control effects of combination of plant induced resistant agents against tobacco mosaic virus (TMV). [ Method] The control effects of 6 different combinations of plant induced resistant agents against TMV of flue-cured tobacco cultivar HongDa were studied under the environment of simulated disease nursery. [ Result] The combination of two induced agents polypeptide-agents and 3-acetonyl-3-hydroxyoxindole (AHO) had good control effect against TMV, which could obviously delay the incidence time of TMV in infected tobacco plants. With water and Duxiao as control, their average control effects against TMV of tobacco plants during field period reached 69.64% and 43.25% after transplanting for 70 d. They also showed obvious superiority in the aspects of plant height and leaf number, and the growth and development condition of leaves was good. Tobacco seedlings carrying TMV virus had no direct correlation with whether the symptoms performed, the seedlings carrying virus would perform symptom only when the incidence condition was suitable. The peak period for the incidence of TMV in seedlings carrying virus was during 19 d after transplanting. Spraying effective agents during nursery stage and field period, as well as promoting early growth and quick tiller of tobacco seedlings after transplanting were the key measures to control its incidence. [Conclusion] The study provided theoretical basis for preparing the control measures against TMV.%[目的]探讨植物诱导抗病剂组合对烟草花叶病的防控效果.[方法]在模拟病圃环境下,研究了6种植物诱导抗病剂的不同组合对烤烟栽培品种红花大金元的烟草花叶病的防控效果.[结果]多肽保与AHO 2种诱导剂的组合应用对控制TMV有良好效果,能明显推迟带毒隐症烟株TMV的发病时间,移栽后70d对以清水和东旺毒消为对照的大田期烟株TMV的平均防效分别达到69.64%和43.25%,且

  17. Mobile Agents

    Science.gov (United States)

    Satoh, Ichiro

    Mobile agents are autonomous programs that can travel from computer to computer in a network, at times and to places of their own choosing. The state of the running program is saved, by being transmitted to the destination. The program is resumed at the destination continuing its processing with the saved state. They can provide a convenient, efficient, and robust framework for implementing distributed applications and smart environments for several reasons, including improvements to the latency and bandwidth of client-server applications and reducing vulnerability to network disconnection. In fact, mobile agents have several advantages in the development of various services in smart environments in addition to distributed applications.

  18. 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

    2016-08-21

    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.

  19. 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.

  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. HPLC-DAD and HPLC-ESI-MS analyses of Tiliae flos and its preparations.

    Science.gov (United States)

    Karioti, A; Chiarabini, L; Alachkar, A; Fawaz Chehna, M; Vincieri, F F; Bilia, A R

    2014-11-01

    In the present study extensive HPLC-DAD, HPLC-ESI-MS and NMR analyses were undertaken in the aqueous preparations (decoctions, infusions) and tinctures of Tilia platyphyllos Scop inflorescences. The aim of this work was to examine in depth the qualitative and quantitative profile of the investigated preparations, which find until today wide applications in pharmaceutical and cosmetic industry, and to propose a validated method for their quality control. An HPLC-DAD-ESI-MS method was developed and optimised for the quantitative determination of the constituents. Marker constituents of Tiliae flos are the flavonoids, while the volatile content is also used for the quality control. However, the analyses of the non-volatile fraction gave complex chromatographic fingerprints containing simple phenolics and low molecular weight procyanidins. The use of different HPLC columns permitted a good separation of the constituents and enabled their quantitation, while HPLC-MS analyses permitted the detection of procyanidin oligomers. Overall, 31 constituents were detected and identified. Extensive preparative chromatographic investigations and 2D-NMR analyses allowed the characterisation of procyanidins as epicatechin derivatives. Finally, the HPLC method was validated and complied with ICH guidelines. This is the first report of detailed analysis of the chemical composition of Tiliae flos.

  2. 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.

  3. 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...

  4. Radioprotective Agents

    Science.gov (United States)

    1982-01-01

    claimed to be effective are gallic acid derivatives, eg, sodium gallate 12053-21-61 (295-297) and propyl gallate 1121-79-91 (298). p...inhibition of a-adrenergic receptors can be achieved through the use of the antiradiation agents 2-(5-aminopentylamino)ethanephos- phorothioic acid ...tissue was ap- preciated immediately as a potential medical set, and they were put to use en- thusiastically. Early workers did notice an erythematous

  5. Simultaneous determination of DTPA, EDTA, and NTA by UV-visible spectrometry and HPLC.

    Science.gov (United States)

    Laine, Pirita; Matilainen, Rose

    2005-08-01

    In this study, UV-visible spectrophotometry (UV-Vis) and high-performance liquid chromatography (HPLC) were used for simultaneous analysis of chelating agents diethylenetriamine pentaacetic acid (DTPA), ethylenediamine tetraacetic acid (EDTA), and nitrilotriacetic acid (NTA), as their metal chelates in dishwashing detergents, natural waters, and pulp mill water. The total amounts of the chelating agents in dishwashing detergents were verified by potentiometric titration with Fe(III) solution. Nickel(II) chelates were determined by UV-Vis and iron(III)chelates by HPLC and titration. Recoveries of DTPA, EDTA, and NTA from a standard mixture of analytes by UV-Vis were 107+/-7, 101+/-12 and 94+/-13%, respectively, and the recovery of the total amount of complexing agents was 99+/-4%. The limits of detection for DTPA, EDTA, and NTA were 667, 324, and 739 micromol L(-1), respectively. In HPLC measurements the optimized mobile phase contained 0.03 mol L(-1) sodium acetate, 0.002 mol L(-1) tetrabutylammonium bromide, and 5% methanol at pH 3.15 and the detection was by UV-Vis detection at 254 nm. All three complexing agents could be separated from each other in a simultaneous analysis in less than 5 min. The limits of detection were 0.34, 0.27, and 0.62 micromol L(-1) for DTPA, EDTA, and NTA, respectively. The total amounts of the analytes measured in the dishwashing detergents by the three techniques were found to be highly comparable (ANOVA: F=0.04, P=0.96). R(2) values were 0.99 for EDTA, 0.99 for NTA, and 0.99 for all the results when UV-Vis and HPLC determinations were compared using regression lines. The UV-Vis and HPLC methods were proved to be viable also for analyses of natural and pulp mill waters. The absence of matrix interferences was verified by the standard addition technique.

  6. 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

    2016-08-05

    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.

  7. Orthogonality of SFC versus HPLC for small molecule library separation.

    Science.gov (United States)

    Weller, Harold N; Ebinger, Katalin; Bullock, William; Edinger, Kurt J; Hermsmeier, Mark A; Hoffman, Steven L; Nirschl, David S; Swann, Thomas; Zhao, Jiang; Kiplinger, Jeffrey; Lefebvre, Paul

    2010-11-08

    Preparative HPLC and HPLC-MS are well established as the methods of choice for purification of pharmaceutical library compounds. Recent advances in supercritical fluid chromatography (SFC) have now made SFC a viable alternative to HPLC for this application. One of the potential arguments for using SFC in place of, or in addition to, HPLC is that it may offer different selectivity and thus has the potential for improved separation success rates. In this paper, we examine relative success rates for SFC and HPLC in obtaining adequate selectivity for successful separation. Our results suggest that use of SFC in addition to HPLC may result in a slight (1-2%) improvement in success rate compared to use of HPLC alone.

  8. 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.

  9. [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.

  10. 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.

  11. 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.

  12. 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

  13. 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...

  14. 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.

  15. 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."

  16. Automatization for development of HPLC methods.

    Science.gov (United States)

    Pfeffer, M; Windt, H

    2001-01-01

    Within the frame of inprocess analytics of the synthesis of pharmaceutical drugs a lot of HPLC methods are required for checking the quality of intermediates and drug substances. The methods have to be developed in terms of optimal selectivity and low limit of detection, minimum running time and chromatographic robustness. The goal was to shorten the method development process. Therefore, the screening of stationary phases was automated by means of switching modules equipped with 12 HPLC columns. Mobile phase and temperature could be optimized by using Drylab after evaluating chromatograms of gradient elutions performed automatically. The column switching module was applied for more than three dozens of substances, e.g. steroidal intermediates. Resolution (especially of isomeres), peak shape and number of peaks turned out to be the criteria for selection of the appropriate stationary phase. On the basis of the "best" column the composition of the "best" eluent was usually defined rapidly and with less effort. This approach leads to savings in manpower by more than one third. Overnight, impurity profiles of the intermediates were obtained yielding robust HPLC methods with high selectivity and minimized elution time.

  17. 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)

    Jean-Christophe Castella

    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

  18. Application of Controlled Freezing Point Technique Combined with Biological Antistaling Agent in Preservation of Aquatic Products%冰温结合生物保鲜剂技术在水产品保鲜中的应用

    Institute of Scientific and Technical Information of China (English)

    杨胜平; 谢晶

    2009-01-01

    The effect of controlled freezing point technique on the quality of aquatic products and the antibacterial function of several common biological antistaling agents were analyzed. The application of food fresh keeping by means of combining these two technologies was also proposed. The review will provide important theoretical basis for the research and enhancement of the application of these two technologies in food industry.%阐述了冰温保鲜技术对水产品品质的影响,以及几种常见生物保鲜剂的抑菌作用.并介绍了冰温贮藏结合生物保鲜剂技术在食品保鲜中的应用,为进一步研究冰温及生物保鲜剂技术和扩大它们在食品工业中的应用提供重要的理论基础.

  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. 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...

  1. 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.

  2. A sensitive and robust HPLC assay with fluorescence detection for the quantification of pomalidomide in human plasma for pharmacokinetic analyses.

    Science.gov (United States)

    Shahbazi, Shandiz; Peer, Cody J; Polizzotto, Mark N; Uldrick, Thomas S; Roth, Jeffrey; Wyvill, Kathleen M; Aleman, Karen; Zeldis, Jerome B; Yarchoan, Robert; Figg, William D

    2014-04-01

    Pomalidomide is a second generation IMiD (immunomodulatory agent) that has recently been granted approval by the Food and Drug Administration for treatment of relapsed multiple myeloma after prior treatment with two antimyeloma agents, including lenalidomide and bortezomib. A simple and robust HPLC assay with fluorescence detection for pomalidomide over the range of 1-500ng/mL has been developed for application to pharmacokinetic studies in ongoing clinical trials in various other malignancies. A liquid-liquid extraction from human plasma alone or pre-stabilized with 0.1% HCl was performed, using propyl paraben as the internal standard. From plasma either pre-stabilized with 0.1% HCl or not, the assay was shown to be selective, sensitive, accurate, precise, and have minimal matrix effects (HPLC-FL assay allows a broader range of laboratories to measure pomalidomide for application to clinical pharmacokinetics.

  3. Development and Validation of Miglitol and Its Impurities by RP-HPLC and Characterization Using Mass Spectrometry Techniques

    OpenAIRE

    Kesavan Balakumaran; Mosesbabu Janagili; Nagaraju Rajana; Sureshbabu Papureddy; Jayashree Anireddy

    2016-01-01

    Alpha glucoside inhibitors used to treat type-2 diabetes mellitus (DM) are likely to be safe and effective. These agents are most effective for postprandial hyperglycemia. Miglitol is a type of drug used to treat type-2 DM. A simple, selective, linear, precise and accurate reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for a related substance of miglitol and its identification, and characterization was done by different mass spectrometry tec...

  4. Lefunomide in combination therapy

    NARCIS (Netherlands)

    Kalden, J.R.; Smolen, J.S.; Emery, P.; Riel, P.L.C.M. van; Dougados, M.; Strand, C.V.; Breedveld, F.C.

    2004-01-01

    In most studies of disease modifying antirheumatic drug therapy, in combination with either leflunomide or biological agents, patients are given an additional agent after they have failed treatment with methotrexate (MTX). This review of clinical studies shows that leflunomide is clinically efficaci

  5. 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.

  6. 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.

  7. HPLC determination of tolperisone in human plasma.

    Science.gov (United States)

    Bae, Jung-Woo; Park, Young-Seo; Sohn, Uy-Dong; Myung, Chang-Sun; Ryu, Byung-Kwon; Jang, Choon-Gon; Lee, Seok-Yong

    2006-04-01

    A simple high performance liquid chromatographic (HPLC) method was developed for the determination of tolperisone in human plasma. Tolperisone and internal standard (chlorphenesin) were isolated from 1 mL of plasma using 8 mL of dichlormethane. The organic phase was collected and evaporated under nitrogen gas. The residue was then reconstituted with 300 mL aliquot of mobile phase and a 100 mL aliquot was injected onto the C18 reverse-phased column. The mobile phase, 45% methanol containing 1% glacial acetic acid and 0.05% 1-hexanesulfonic acid was run at a flow rate of 1 mL/min. The column effluent was monitored using UV detector at 260 nm. The retention times for tolperisone and the internal standard were approximately 7.1 and 8.4 min, respectively. The standard curve was linear with minimal intra-day and inter-day variability. The quantification limit of tolperisone in human plasma was 10 ng/ mL. The proposed method has been applied to the determination of pharmacokinetic profile of tolperisone in Koreans. The Tmax of tolperisone in Koreans (0.94 +/- 0.42 h) was not significantly differ from that reported in Europeans (0.5-1 h), but the mean half-life in Koreans (1.14 +/- 0.27 h) was shorter than that in Europeans (2.56 +/- 0.2 h). The proposed HPLC method is simple, accurate, reproducible and suitable for pharmacokinetic study of tolperisone.

  8. The comparison of determination of ciprofloxacin by HPLC-UV and HPLC-ELSD%HPLC-UV与HPLC-ELSD测定环丙沙星含量之比较

    Institute of Scientific and Technical Information of China (English)

    乔成孝; 裴朝玉; 陈晓刚; 方国波

    2006-01-01

    目的:探讨利用HPLC-紫外检测器(UV)和HPLC-蒸发光散射检测器(Evaporative light scattering detector, ELSD )测定乳酸环丙沙星氯化钠注射液中环丙沙星含量,比较两种检测方法的优劣.方法:色谱条件为:色谱柱:Kromasil C-18,5μ,250×4.6mm;流动相:三氟乙酸∶乙腈=80∶20(V/V);流速:1mL/min;柱温:25℃;检测波长:277nm;蒸发光散射检测器条件:雾化温度30℃,漂移管温度65℃.结果:环丙沙星注射液中的各种成分在上述色谱条件下能完全分离,分析时间仅需20min;两种测定方法结果一致.结论:紫外检测器更加灵敏和稳定,而蒸发光散射检测器则适用于更多的物质.

  9. Comprehensive quality evaluation of Chishao by HPLC

    Directory of Open Access Journals (Sweden)

    Jian Zaiyou

    2013-10-01

    Full Text Available Objective: The purpose of this paper is to comprehensively evaluate the quality of Chishao. Methods: In the experiment of this paper, the fingerprint spectrums of Chishao in all locations are established by RP-HPLC and the model of principle component analysis with the RP-HPLC peak areas is established. Results: The quality of Chishao in the northern part of China or that made of Paeonia lactiflora is better than that of these in others or that made of other species. The quality of Chishao comes from P. veitchii is in the middle class and is better than those that comes from P. obovata, P. mairei and P. anomala. The results are consistent with traditional views of the quality of this plant. These results indicates that principal component analysis (PCA can be used as an effective and economic method to evaluate the quality of Chishao, and may be extended to other Chinese medicinal plants. Conclusions: Due to the complex basis of the efficacy of Traditional Chinese Medicine (TCM, the method such as PCA of several chemical components appears to be a more appropriate method for the quality evaluation of TCM in contrast to the determination of a single or few chemicals.

  10. Targeted natural products discovery from marine cyanobacteria using combined phylogenetic and mass spectrometric evaluation.

    Science.gov (United States)

    Salvador-Reyes, Lilibeth A; Engene, Niclas; Paul, Valerie J; Luesch, Hendrik

    2015-03-27

    Combined phylogenetic and HPLC-MS-based natural products dereplication methods aimed at identifying cyanobacterial collections containing the potent cytotoxins largazole, dolastatin 10, and symplostatin 1 were developed. The profiling of the phylogeny, chemical space, and antiproliferative activity of cyanobacterial collections served to streamline the prioritization of samples for the discovery of new secondary metabolites. The dereplication methods highlighted the biosynthetic potential and combinatorial pharmacology employed by marine cyanobacteria. We found that largazole was always coproduced with dolastatin 10 or with symplostatin 1 and consequently tested combinations of these agents against colon cancer cells. Combinatorial regimens of largazole and dolastatin 10 aimed at curbing the growth of HCT116 cancer cells showed cooperative activity.

  11. Screening and Analysis of the Potential Bioactive Components of Poria cocos (Schw.) Wolf by HPLC and HPLC-MS(n) with the Aid of Chemometrics.

    Science.gov (United States)

    Wu, Ling-Fang; Wang, Kun-Feng; Mao, Xin; Liang, Wen-Yi; Chen, Wen-Jing; Li, Shi; Qi, Qi; Cui, Ya-Ping; Zhang, Lan-Zhen

    2016-02-18

    The aim of the present study was to establish a new method based on Similarity Analysis (SA), Cluster Analysis (CA) and Principal Component Analysis (PCA) to determine the quality of different samples of Poria cocos (Schw.) Wolf obtained from Yunnan, Hubei, Guizhou, Fujian, Henan, Guangxi, Anhui and Sichuan in China. For this purpose 15 samples from the different habitats were analyzed by HPLC-PAD and HPLC-MS(n). Twenty-three compounds were detected by HPLC-MS(n), of which twenty compounds were tentatively identified by comparing their retention times and mass spectrometry data with that of reference compounds and reviewing the literature. The characteristic fragmentations were summarized. 3-epi-Dehydrotumulosic acid (F13), 3-oxo-16α,25-dihydroxylanosta-7,9(11),24(31)-trien-21-oic acid (F4), 3-oxo-6,16α-dihydroxylanosta-7,9(11),24(31)-trien-21-oic acid (F7) and dehydropachymic acid (F15) were deemed to be suitable marker compounds to distinguish between samples of different quality according to CA and PCA. This study provides helpful chemical information for further anti-tumor activity and active mechanism research on P. cocos. The results proved that fingerprint combined with a chemometric approach is a simple, rapid and effective method for the quality discrimination of P. cocos.

  12. Screening and Analysis of the Potential Bioactive Components of Poria cocos (Schw. Wolf by HPLC and HPLC-MSn with the Aid of Chemometrics

    Directory of Open Access Journals (Sweden)

    Ling-Fang Wu

    2016-02-01

    Full Text Available The aim of the present study was to establish a new method based on Similarity Analysis (SA, Cluster Analysis (CA and Principal Component Analysis (PCA to determine the quality of different samples of Poria cocos (Schw. Wolf obtained from Yunnan, Hubei, Guizhou, Fujian, Henan, Guangxi, Anhui and Sichuan in China. For this purpose 15 samples from the different habitats were analyzed by HPLC-PAD and HPLC-MSn. Twenty-three compounds were detected by HPLC-MSn, of which twenty compounds were tentatively identified by comparing their retention times and mass spectrometry data with that of reference compounds and reviewing the literature. The characteristic fragmentations were summarized. 3-epi-Dehydrotumulosic acid (F13, 3-oxo-16α,25-dihydroxylanosta-7,9(11,24(31-trien-21-oic acid (F4, 3-oxo-6,16α-dihydroxylanosta-7,9(11,24(31-trien-21-oic acid (F7 and dehydropachymic acid (F15 were deemed to be suitable marker compounds to distinguish between samples of different quality according to CA and PCA. This study provides helpful chemical information for further anti-tumor activity and active mechanism research on P. cocos. The results proved that fingerprint combined with a chemometric approach is a simple, rapid and effective method for the quality discrimination of P. cocos.

  13. Effects of EDTA Combining with Two Kinds of Antimicrobial Agents on Saprolegnia Biofilm%EDTA 联合抗菌药对水霉菌生物膜的影响

    Institute of Scientific and Technical Information of China (English)

    袁海兰; 欧仁建; 胡鲲; 杨先乐

    2015-01-01

    The clean-up effect of EDTA,a metal-chelator,was investigated when used alone or combined with antimicrobial agents on Saprolegnia biofilm.The minimal inhibitory concentration (MIC)of EDTA to Saprolegnia spore was measured by microdilution broth method.Saprolegnia biofilms were treated by common and 2 times dose of anti-Saprolegnia drugs.Meanwhile,Saprolegnia biofilms were treated by 1 MIC,4 MIC and 16 MIC EDTA combining with common dose of methylene blue and Mei Ting,respective-ly.And then all results were measured by the CCK-8 (Cell Counting Kit-8).Furthermore,the biofilm treated by EDTA was stained with calcofluor white M2R,observed by fluorescence microscope,to investi-gate the change of the extracellular maxtrix.The results showed that,compared with the control group,it played no significant role when the biofilms were treated by common dose of methylene blue and Mei Ting respectively(P >0.05),the same as 2 times dose of methylene blue,but it changed when combining with EDTA.And the extracellular maxtrix of Saprolegnia biofilm reduced after being treated by EDTA.In conclusion,EDTA could destroy the structure of biofilm.The combination of EDTA with anti-Saproleg-nia drugs had significant activity to remove Saprolegnia biofilm.%为探索金属离子螯合剂乙二胺四乙酸(EDTA)单独及联合抗菌药物对水霉菌生物膜的清除效应,采用微量稀释法测定 EDTA 对水霉菌游动孢子最小抑菌浓度(MIC)。用常用剂量和2倍剂量抗菌药亚甲基蓝、美婷及1、4、16倍 MIC 的 EDTA 联合二者常用剂量分别作用于水霉菌生物膜,CCK-8法检测药物作用后生物膜活力变化。并用 Calcofluor White M2R 染色 EDTA 处理后水霉菌生物膜,荧光显微镜观察胞外基质变化。结果显示,亚甲基蓝、美婷在常用剂量下作用于水霉菌生物膜效果不佳,与对照组无显著性差异(P >0.05),亚甲基蓝在2倍剂量下仍不能发挥较好的效果

  14. MOBILE AGENT: EMERGING TECHNOLOGY

    OpenAIRE

    RAJGURU P. V. DR. DESHMUKH S. D

    2011-01-01

    Mobile agent technology has been promoted as an emerging technology that makes it much easier to design, implement, and maintain distributed systems, introduction to basic concepts of mobile agents like agent mobility, agent types and places and agent communication. Then benefits of the usage of mobile agents are summarized and illustrated by selected applications. The next section lists requirements and desirable properties for mobile agent languages and systems. We study the main features, ...

  15. 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.)

  16. The effect of re-dissolution solvents and HPLC columns on the analysis of mycosporine-like amino acids in the eulittoral macroalgae Prasiola crispa and Porphyra umbilicalis

    Science.gov (United States)

    Karsten, Ulf; Escoubeyrou, Karine; Charles, François

    2009-09-01

    Many macroalgal species that are regularly exposed to high solar radiation such as the eulittoral green alga Prasiola crispa and the red alga Porphyra umbilicalis synthesize and accumulate high concentrations of mycosporine-like amino acids (MAAs) as UV-sunscreen compounds. These substances are typically extracted with a widely used standard protocol following quantification by various high performance liquid chromatography (HPLC) techniques. However, further preparation steps prior to HPLC analysis as well as different HPLC column types have not been systematically checked regarding separation quality and reproducibility. Therefore pure methanol, distilled water and HPLC eluent were evaluated as re-dissolution solvent for dried Prasiola and Porphyra extracts, which were subsequently analyzed on three reversed-phase C8 and C18 HPLC columns. The data indicate that distilled water and the HPLC eluent gave almost identical peak patterns and MAA contents on the C8 and C18 columns. In contrast, the application of the widely used methanol led to double peaks or even the loss of specific peaks as well as to a strong decline in total MAA amounts ranging from about 35% of the maximum in P. crispa to 80% of the maximum in P. umbilicalis. Consequently, methanol should be avoided as re-dissolution solvent for the HPLC sample preparation. An improved protocol for the MAA analysis in macroalgae in combination with a reliable C18 column is suggested.

  17. 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)

  18. 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…

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

    Institute of Scientific and Technical Information of China (English)

    LI Guo-chen; WANG Yan-hong; WU Ren-an; WANG Shi-cheng

    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 offiine 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.

  20. 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.

  1. 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.

  2. 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.

  3. Analytical Method Development and Validation for Simultaneous Estimation of Clotrimazole and Tinidazole by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Joshi S

    2015-12-01

    Full Text Available An isocratic reverse phase High Performance Liquid Chromatographic (RP-HPLC method was developed and validated for simultaneous determination of Clotrimazole and Tinidazole in combined pharmaceutical dosage form. The successful separation of Clotrimazole and Tinidazole was achieved using Purospher® C18 (250 mm x 4.6 mm i.d., 5 μm column, with mobile phase consisting Phosphate buffer (pH 3.5: Acetonitrile (45:55. The mobile phase flow rate was 1.0 ml/min and the detection wavelength was 240 nm. The developed RP-HPLC method was validated according to ICH guidelines with respect to linearity, accuracy, precision, specificity and robustness and also the LOD and LOQ values were determined.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. Traditional Chinese Medicine Combined with Antifungal Agents for Treating Fungal Keratitis in 53 Cases%中药联合抗真菌药物治疗真菌性角膜炎53例

    Institute of Scientific and Technical Information of China (English)

    邓显峰

    2015-01-01

    Objective To observe the clinical effect of traditional Chinese medicine combined with antifungal agents in treating fungal keratitis. Methods Totally 106 patients with fungal keratitis in the hospital were selected and divided into the experimental group and the control group,53 cases each. The control group adopted 5% Natamycin Eye Drops and 0. 2% Fluconazole Eye Drops for treatment, while on this basis the experimental group adopted oral Yupingfeng Powder and Yinhuatufuling Decoction,and traditional Chinese medicine fumigation eye treatment. The curative effect,vision,adverse reactions and cure time after 15 d treatment were evaluat-ed. Results The experimental group was significantly better than the control group in the curative effect,visual acuity and cure time ( P ﹤ 0. 05);the adverse reactions had no statistically significant difference between the two groups. Conclusion The integrated tradi-tional Chinese and Western medicine for treating fungal keratitis can obtain better curative effect,shorten the cure time and deserves to be promoted in clinic.%目的:观察中药联合抗真菌药物治疗真菌性角膜炎的临床疗效。方法选取医院诊治的真菌性角膜炎患者106例,按就诊先后顺序将其分为试验组和对照组,各53例。对照组患者采用5%那他霉素滴眼液和0.2%氟康唑滴眼液滴眼治疗,试验组患者在对照组基础上采用玉屏风散合银花土茯苓汤内服和中药熏蒸患眼治疗。治疗15 d后进行疗效、视力、不良反应、痊愈时间等评估。结果试验组的疗效、视力和痊愈时间均明显优于对照组( P﹤0.05),两组患者不良反应发生情况无显著性差异。结论中西医结合治疗真菌性角膜炎可取得较好疗效,能缩短痊愈时间,值得临床推广。

  10. 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

  11. Riot Control Agents

    Science.gov (United States)

    ... Submit What's this? Submit Button Facts About Riot Control Agents Interim document Recommend on Facebook Tweet Share Compartir FACT SHEET What riot control agents are Riot control agents (sometimes referred to ...

  12. 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.

  13. Agent-Oriented Probabilistic Logic Programming

    Institute of Scientific and Technical Information of China (English)

    Jie Wang; Shi-Er Ju; Chun-Nian Liu

    2006-01-01

    Currently, agent-based computing is an active research area, and great efforts have been made towards the agent-oriented programming both from a theoretical and practical view. However, most of them assume that there is no uncertainty in agents' mental state and their environment. In other words, under this assumption agent developers are just allowed to specify how his agent acts when the agent is 100% sure about what is true/false. In this paper, this unrealistic assumption is removed and a new agent-oriented probabilistic logic programming language is proposed, which can deal with uncertain information about the world. The programming language is based on a combination of features of probabilistic logic programming and imperative programming.

  14. HPLC retention thermodynamics of grape and wine tannins.

    Science.gov (United States)

    Barak, Jennifer A; Kennedy, James A

    2013-05-08

    The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality.

  15. Quality assessment of cortex cinnamomi by HPLC chemical fingerprint, principle component analysis and cluster analysis.

    Science.gov (United States)

    Yang, Jie; Chen, Li-Hong; Zhang, Qin; Lai, Mao-Xiang; Wang, Qiang

    2007-06-01

    HPLC fingerprint analysis, principle component analysis (PCA), and cluster analysis were introduced for quality assessment of Cortex cinnamomi (CC). The fingerprint of CC was developed and validated by analyzing 30 samples of CC from different species and geographic locations. Seventeen chromatographic peaks were selected as characteristic peaks and their relative peak areas (RPA) were calculated for quantitative expression of the HPLC fingerprints. The correlation coefficients of similarity in chromatograms were higher than 0.95 for the same species while much lower than 0.6 for different species. Besides, two principal components (PCs) have been extracted by PCA. PC1 separated Cinnamomum cassia from other species, capturing 56.75% of variance while PC2 contributed for their further separation, capturing 19.08% variance. The scores of the samples showed that the samples could be clustered reasonably into different groups corresponding to different species and different regions. The scores and loading plots together revealed different chemical properties of each group clearly. The cluster analysis confirmed the results of PCA analysis. Therefore, HPLC fingerprint in combination with chemometric techniques provide a very flexible and reliable method for quality assessment of traditional Chinese medicines.

  16. Biological warfare agents.

    Science.gov (United States)

    Pohanka, Miroslav; Kuca, Kamil

    2010-01-01

    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  17. 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.

  18. HPLC Quantification of Flavonoids and Biflavonoids in Cupressaceae Leaves

    OpenAIRE

    A. Romani; C. GALARDI; P. PINELLI; Mulinacci, N.; D. HEIMLER

    2002-01-01

    The aim of this investigation was to obtain qualitative and quantitative profiles of the flavonoid and biflavonoid composition of six cypress species - Cupressus funebris L., Cupressus semper- Wrens L., Cupressus glabra L., Cupressus arizonica L., Cupressus goveniana L., and Cupressus lusitanica L. HPLC-diode-array detection (DAD), HPLC-MS, and HPTLC were used to identify the individual compounds. A chromatographic method was optimized for identification and quantification of t...

  19. 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.

  20. Time-resolved SAXS measurements facilitated by online HPLC buffer exchange

    DEFF Research Database (Denmark)

    Jensen, Malene Hillerup; Toft, Katrine Nørgaard; David, Gabriel

    2010-01-01

    be possible to separate contributions from individual species present in solution. Hence, time-resolved SAXS (TR-SAXS) data of processes in development can be analyzed. Many reported TR-SAXS results are initialized by a sudden change in buffer conditions facilitated by rapid mixing combined with either...... continuous or stopped flow. In this paper a method for obtaining TR-SAXS data from systems where the reaction is triggered by removal of a species is presented. This method is based on fast buffer exchange over a short desalting column facilitated by an online HPLC (high-performance liquid chromatography...

  1. 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.

  2. 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.

  3. Determination of memantine in plasma and vitreous humour by HPLC with precolumn derivatization and fluorescence detection.

    Science.gov (United States)

    Puente, Belen; Hernandez, Esther; Perez, Susana; Pablo, Luis; Prieto, Esther; Garcia, Maria Angeles; Bregante, Miguel Angel

    2011-01-01

    A new HPLC procedure with precolumn derivatization and rimantadine as the internal standard for determining memantine, a candidate agent for the treatment of glaucoma in plasma and vitreous humour, has been developed and validated. Precolumn derivatization was performed with 9-fluorenylmethyl-chloroformate-chloride (FMOC-Cl) as the derivatization reagent and followed by a liquid-liquid extraction with n-hexane. Optimal conditions for derivatization were an FMOC-Cl concentration of 1.5 mM, a reaction time of 20 min, the temperature at 30°C, the borate buffer pH 8.5, and a borate buffer-acetonitrile ratio of 1:1. The derivatives were analyzed by isocratic HPLC with the fluorescence detector λex 260 nm λem 315 nm on a Novapack C(18) reversed-phase column with a mobile phase of acetonitrile-water (73:27, v/v), 40°C, and a flow rate of 1.2 mL/min. The linear range was 10-1000 ng/mL with a quantification limit of ∼ 10 ng/mL for both types of samples. This analytical method may be suitable for using in ocular availability studies.

  4. 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.

  5. Animal Capture Agents

    Science.gov (United States)

    1990-01-01

    agents and delivery systems reviewed . Questionnaires were sent to 137 Air Force bases to obtain information about the chemical agents and delivery systems...used by animal control personnel. A literature review included chemical agents, delivery methods, toxicity information and emergency procedures from...34-like agent. Users should familiarize themselves with catatonia in general and particularly that its successful use as an immobilizer doesn’t necessarily

  6. Quality Evaluation and Chemical Markers Screening of Salvia miltiorrhiza Bge. (Danshen Based on HPLC Fingerprints and HPLC-MSn Coupled with Chemometrics

    Directory of Open Access Journals (Sweden)

    Wenyi Liang

    2017-03-01

    Full Text Available Danshen, the dried root of Salvia miltiorrhiza Bge., is a widely used commercially available herbal drug, and unstable quality of different samples is a current issue. This study focused on a comprehensive and systematic method combining fingerprints and chemical identification with chemometrics for discrimination and quality assessment of Danshen samples. Twenty-five samples were analyzed by HPLC-PAD and HPLC-MSn. Forty-nine components were identified and characteristic fragmentation regularities were summarized for further interpretation of bioactive components. Chemometric analysis was employed to differentiate samples and clarify the quality differences of Danshen including hierarchical cluster analysis, principal component analysis, and partial least squares discriminant analysis. Consistent results were that the samples were divided into three categories which reflected the difference in quality of Danshen samples. By analyzing the reasons for sample classification, it was revealed that the processing method had a more obvious impact on sample classification than the geographical origin, it induced the different content of bioactive compounds and finally lead to different qualities. Cryptotanshinone, trijuganone B, and 15,16-dihydrotanshinone I were screened out as markers to distinguish samples by different processing methods. The developed strategy could provide a reference for evaluation and discrimination of other traditional herbal medicines.

  7. Intelligent Agents: A Primer.

    Science.gov (United States)

    Yu, Edmund; Feldman, Susan

    1999-01-01

    Provides an in-depth introduction to the various technologies that are bringing intelligent agents into the forefront of information technology, explaining how such agents work, the standards involved, and how agent-based applications can be developed. (Author/AEF)

  8. 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

  9. 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...

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION OF OFLOXACCIN AND SATRANIDAZOLE BY USING RP-HPLC

    Directory of Open Access Journals (Sweden)

    K. S. Nataraj

    2013-08-01

    Full Text Available A new simple, accurate, rapid and precise gradient High Performance Liquid Chromatographic (HPLC method was developed and validated for simultaneous estimation of Ofloxaccin and satranidazole in combined dosage form. The method employs waters HPLC system on Hypersil BDS C18 Column (250 mm X 4.6 mm, 5 µ, with a flow rate of 1.0 ml / min with a load of 10 µl. Water + OPA (Ortho Phosphoric Acid having pH 5.0 and acetonitrile was used as a mobile phase in the composition of 60:40 % v/v. The detection was carried out by PDA detector at 295 nm. Linearity ranges for Ofloxaccin and satranidazole were 100 – 300 g / ml for Ofloxaccin, 150 – 450 g / ml for satranidazole respectively. Retention time of Ofloxaccin and Satranidazole were found to be 2.881 minutes, 4.042 minutes respectively. Percent recovery study values of Ofloxaccin and Satranidazole were found to be 99.003 – 100.5 % and 98.6 – 100.4 % respectively. This newly developed method was successfully utilized for the quantitative estimation of Ofloxaccin and Satranidazole in combined pharmaceutical dosage forms. This method was validated as per ICH guidelines.

  15. 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.

  16. 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。

  17. 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.

  18. HarTAC– The Harvard TAC SCM'03 Agent

    OpenAIRE

    Dong, Rui; Tai, Terry; Yeung, Wilfred; Parkes, David C.

    2004-01-01

    The Trading Agent Competition (TAC) is an annual event in which teams from around the world compete in a given scenario concerning the trading agent problem. This paper describes some of the key features and strategies employed by HarTAC, the Harvard University TAC SCM 2003 agent. HarTAC was built to be a moderately aggressive, production-oriented agent, combining a semi-conservative component purchasing strategy with a highly aggressive cycle-based sell side.

  19. 复合生防菌群对连作大豆根际土壤可培养微生物区系的影响%Effects of combined biocontrol agents on soybean rhizosphere culturable microbial flora from continuous soybean cropping soil

    Institute of Scientific and Technical Information of China (English)

    范文艳; 陈瑾; 姜述君; 于涵; 张国庆; 刘朝

    2012-01-01

    Pot experiments were carried out to investigate the effect of combined biocontrol agents on rhizosphere microbial flora of soybean (Glycine max) in continuous cropping soil. Results showed thai combined biocontrol agents could effectively change soil microbial flora in soybean rhizosphere. Among different growth stages of soybean, the quantities of bacteria, fungi and actinomyces had changed evidently under combined biocontrol agents treatment. In euphylla period and compound leaf period, rhizosphere bacteria increased 71. 8% and 114. 3% , while fungus decreased 12.9% and 22. 3% respectively. Actinomyces decreased 9.9% in euphylla period, but increased 27.4% in compound leaf period. The results showed that combined biocontrol agents significantly reduced the proportions of soilborne pathogene of Fusarium and Rhizoctonia in soybean rhizosphere, and enhanced the proportions of beneficial microbes including Rhizobium, Azotobacter, Trichoderma, Pseudomonas and Bacillus.%采用盆栽试验,研究了复合生防菌群对大豆根际土壤可培养微生物区系的调节作用.结果表明,复合生防菌群可以明显改变大豆根际微生物区系组成.在大豆不同时期,复合生防菌群处理的大豆根际细菌、真菌和放线菌在数量上发生了较大改变.在大豆真叶期和复时期,复合生防菌群接种处理大豆根际细菌较对照增幅分别达到71.8%和114.3%,而根际真菌较对照减少12.9%和22.3%.在大豆真叶期,复合生防菌群接种处理大豆根际放线菌数量较对照减少9.9%,而在复叶期,根际放线菌数量较对照增加27.4%.此外,施用复合生防菌群可有效降低土传病原菌镰孢菌属(Fusarium)和丝核菌属(Rhizoctonia)的比例,并且提高根瘤菌(Rhtizobium)、固氮菌(Azotobacter)、木霉属(Trichoderma)、假单胞菌属(Pseudomonas)和芽孢杆菌属(Bacillus)等有益菌的比例.

  20. 舒必利联合质子泵抑制剂、黏膜保护剂治疗反流性胃炎的疗效分析%Curative effect analysis of sulpiride combined with proton pump inhibitor and mucosal protective agent in the treatment of reflux gastritis

    Institute of Scientific and Technical Information of China (English)

    何舟伦

    2015-01-01

    Objective:To explore the curative effect of sulpiride combined with proton pump inhibitor and mucosal protective agent in the treatment of reflux gastritis.Methods:95 cases of patients with reflux gastritis from April 2013 to April 2014 were randomly divided into the research group(48 cases) and the control group(47 cases).The control group were given domperidone combined with proton pump inhibitor and mucosal protective agent,and the research group were given sulpiride combined with proton pump inhibitor and mucosal protective agent.We analyzed the symptom scores and adverse reactions of the two groups. Results:The each symptom scores of the research group after treatment were lower than those of the control group(P0.05).Conclusion:Sulpiride combined with proton pump inhibitor and mucosal protective agent in the treatment of reflux gastritis has obvious curative effect and safety.%目的:探究舒必利联合质子泵抑制剂(PPI)、黏膜保护剂治疗反流性胃炎的效果。方法:2013年4月-2014年4月收治反流性胃炎患者95例,随机分为研究组48例和对照组47例。对照组予以吗丁啉联合PPI、黏膜保护剂治疗,研究组予以舒必利联合PPI、黏膜保护剂治疗,分析两组症状评分和不良反应情况。结果:治疗后研究组各症状评分均低于对照组(P<0.05)。两组不良反应发生率差异无统计学意义(P>0.05)。结论:舒必利联合PPI、黏膜保护剂治疗反流性胃炎疗效显著,安全性较好。

  1. 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...

  2. Empirically Based, Agent-based models

    Directory of Open Access Journals (Sweden)

    Elinor Ostrom

    2006-12-01

    Full Text Available There is an increasing drive to combine agent-based models with empirical methods. An overview is provided of the various empirical methods that are used for different kinds of questions. Four categories of empirical approaches are identified in which agent-based models have been empirically tested: case studies, stylized facts, role-playing games, and laboratory experiments. We discuss how these different types of empirical studies can be combined. The various ways empirical techniques are used illustrate the main challenges of contemporary social sciences: (1 how to develop models that are generalizable and still applicable in specific cases, and (2 how to scale up the processes of interactions of a few agents to interactions among many agents.

  3. 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.

  4. Analysis of limette and bergamot distilled essential oils by HPLC.

    Science.gov (United States)

    Buiarelli, Francesca; Cartoni, Giampaolo; Coccioli, Franco; Jasionowska, Renata; Mazzarino, Monica

    2002-04-01

    This work examines the distilled essential oils of limette and bergamot in order to assess the presence of low volatile substances such as coumarins (bergapten) which, being toxic, must be eliminated before using these oils in the food industry. The quantitative determination of coumarins was carried out by spectrofluorimetric detection. The substances present in the chromatograms, obtained by HPLC with UV detection at 254 nm, were then identified. Moreover, a new coumarin that is present in small quantities was identified using HPLC-MS.

  5. 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.

  6. Moral actor, selfish agent.

    Science.gov (United States)

    Frimer, Jeremy A; Schaefer, Nicola K; Oakes, Harrison

    2014-05-01

    People are motivated to behave selfishly while appearing moral. This tension gives rise to 2 divergently motivated selves. The actor-the watched self-tends to be moral; the agent-the self as executor-tends to be selfish. Three studies present direct evidence of the actor's and agent's distinct motives. To recruit the self-as-actor, we asked people to rate the importance of various goals. To recruit the self-as-agent, we asked people to describe their goals verbally. In Study 1, actors claimed their goals were equally about helping the self and others (viz., moral); agents claimed their goals were primarily about helping the self (viz., selfish). This disparity was evident in both individualist and collectivist cultures, attesting to the universality of the selfish agent. Study 2 compared actors' and agents' motives to those of people role-playing highly prosocial or selfish exemplars. In content (Study 2a) and in the impressions they made on an outside observer (Study 2b), actors' motives were similar to those of the prosocial role-players, whereas agents' motives were similar to those of the selfish role-players. Study 3 accounted for the difference between the actor and agent: Participants claimed that their agent's motives were the more realistic and that their actor's motives were the more idealistic. The selfish agent/moral actor duality may account for why implicit and explicit measures of the same construct diverge, and why feeling watched brings out the better angels of human nature.

  7. The application of HPLC with on-line coupled UV/MS-biochemical detection for isolation of an acetylcholinesterase inhibitor from narcissus 'Sir Winston Churchill'.

    Science.gov (United States)

    Ingkaninan, K; Hazekamp, A; de Best, C M; Irth, H; Tjaden, U R; van der Heijden, R; van der Greef, J; Verpoorte, R

    2000-06-01

    An HPLC with on-line coupled UV/MS-biochemical detection method for acetylcholinesterase (AChE) inhibitors in natural sources has been developed. The potential of this method is shown by the isolation of a new AChE inhibitor from the alcoholic extract of Narcissus 'Sir Winston Churchill'. Combining a prefractionation technique using centrifugal partition chromatography with the on-line HPLC-UV/MS-biochemical detection resulted in the isolation of the active compound that was identified as ungiminorine. This alkaloid shows a mild inhibitory effect on AChE.

  8. Mobile agent security using proxy-agents and trusted domains

    OpenAIRE

    Mitrovic, Nikola; Arronategui Arribalzaga, Unai

    2009-01-01

    Commercial or wide-network deployment of Mobile Agent Systems is not possible without satisfying security architecture. In this paper we propose architecture for secure Mobile Agent Systems, using Trusted Domains and Proxy agents. Existing approaches are based on security services at the level of an agent system, library or specific objects. Our concept uses proxy agents to enable transparent security services both to security-aware mobile agents and legacy agents. Per-agent and domain-level...

  9. 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.

  10. An Agent for the Prospect Presentation Problem

    Science.gov (United States)

    2014-05-01

    example is a medical system which assists a doc- tor or patient in deciding whether to use a certain medica - tion. The medication is associated with one...affects the users’ interaction with the agent. We chose the pie charts (combined and separate) in order to enhance com- prehension of the proposed...Z. Rabinovich, S. Kraus, C. V. Goldman, and Y. Gal. Strategic advice provision in repeated human-agent interactions . In AAAI, 2012. [5] A. Azaria, Z

  11. Pyridinium Oxime Compounds as Antimicrobial Agents

    Science.gov (United States)

    2007-08-01

    incident combinant les agents neurotoxiques et biologiques ne serait probablement pas efficace contre l’agent biologique, surtout s’il s’agit du charbon ...Nelson, K., and Beverley, S. M. (1993). Evolution of the nuclear ribosomal RNAs in kinetoplastid protozoa: perspectives on the age and origins of...indexing annotation must be entered when the overall document is classified) ORIGINATOR (The name and address of the organization preparing the document

  12. 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.

  13. 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.

  14. Agent Architectures for Compliance

    Science.gov (United States)

    Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua

    A Normative Multi-Agent System consists of autonomous agents who must comply with social norms. Different kinds of norms make different assumptions about the cognitive architecture of the agents. For example, a principle-based norm assumes that agents can reflect upon the consequences of their actions; a rule-based formulation only assumes that agents can avoid violations. In this paper we present several cognitive agent architectures for self-monitoring and compliance. We show how different assumptions about the cognitive architecture lead to different information needs when assessing compliance. The approach is validated with a case study of horizontal monitoring, an approach to corporate tax auditing recently introduced by the Dutch Customs and Tax Authority.

  15. 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.

  16. Application of 2D-HPLC/taste dilution analysis on taste compounds in aniseed (Pimpinella anisum L.).

    Science.gov (United States)

    Pickrahn, Stephen; Sebald, Karin; Hofmann, Thomas

    2014-09-24

    This is the first application of fully automated, preparative, two-dimensional HPLC combined with sensory analysis for taste compound discovery using a sweet and licorice-like bitter-tasting aniseed extract as an example. Compared to the traditional iterative fractionation of food extracts by sensory-guided sequential application of separation techniques, the fully automated 2D-HPLC allowed the comprehensive separation of the aniseed extract into 256 subfractions and reduced the fractionation time from about 1 week to <1day. Using a smart sensory strategy to locate high-impact fractions, e.g., by evaluating first-dimension fractions by reconstituting them from second-dimension subfractions, followed by straightforward application of the taste dilution analysis on the individual second-dimension subfractions revealed the sweet-tasting trans-anethole and the bitter-tasting trans-pseudoisoeugenol 2-methylbutyrate, showing recognition thresholds of 70 and 68 μmol/L, respectively, as the primary orosensory active compounds in aniseed. 2D-HPLC combined with smart sensory analysis seems to be a promising strategy to speed the discovery of the key players imparting the attractive taste of foods.

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. 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...

  2. 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.

  3. 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.

  4. Determination of Interfacial Parameters of Copolyamide Membrane Material by HPLC

    Institute of Scientific and Technical Information of China (English)

    张秀真; 高素莲; 陈均

    2003-01-01

    The High Performance Liquid Chromatography (HPLC) method is employed with copolyamide-170 (PA-170) membrane material as packing to determine the retention volume (V'R) and equilibrium distribution coefficient (K'A) of both inorganic solutes and organic solutes. Based on the experimental data, the interfacial parameters of the packing material are obtained.

  5. SCREENING CORD BLOOD FOR HEMOGLOBINOPATHIES AND THALASSEMIA BY HPLC

    NARCIS (Netherlands)

    VANDERDIJS, FPL; VANDENBERG, GA; SCHERMER, JG; MUSKIET, FD; LANDMAN, H; MUSKIET, FAJ

    1992-01-01

    We evaluated the use of an HPLC method for screening hemoglobins in cord blood. We studied the genotype frequencies of the structural hemoglobin variants HbS and HbC and the synthesis variants alpha- and beta+-thalassemia in babies born on Curacao. During three months, 67.2% of all (748) newborns we

  6. Ultratraces of carotenes in tomato purees : HPLC-TLS study

    NARCIS (Netherlands)

    Luterotti, S.; Markovic, K.; Franko, M.; Bicanic, D.D.; Vahcic, N.; Doka, O.

    2003-01-01

    The present study was designed to provide information about (i) the profile of carotene pigments and (ii) trace quantities of lycopene and -carotene left in tomato purées. The ultrasensitive method comprising HPLC and thermal lens spectrometric (TLS) detection enabled us to detect as low as 0.3 and

  7. Determination of trace diethylstilbestrol in urine by hollow fiber membrane/liquid-phase microextraction combined with HPLC%中空纤维膜液相微萃取-高效液相色谱联用技术测定尿液中痕量己烯雌酚

    Institute of Scientific and Technical Information of China (English)

    张玉; 刘雷英

    2012-01-01

    采用中空纤维液相微萃取与高效液相色谱联用技术测定了尿液样品中的痕量己烯雌酚;考察了样品相酸度、中间相种类、接收相浓度、搅拌速度、萃取时间等对液-液-液三相微萃取效率的影响,进而确定了最佳萃取条件.结果表明,当样品相pH为2.5,中间相为甲苯,接收相为3μL 0.25 mol/L氢氧化钠溶液,搅拌速度为800r/min,萃取时间为50 min时,萃取效率最佳.在最佳萃取条件下,样品的回收率为76.4%,相对标准偏差为3.8%.%Trace diethylstilbestrol in urine samples was determined by combining hollow fiber membrane/liquid-phase microextraction with high performance liquid chromatography. The effects of donor phase pH, intermediate type, acceptor phase concentration, stirring rate, and extraction time on liquid-liquid-liquid tri-phase microextraction efficiency were investigated, and the optimal microextraction condition was established accordingly. Results indicate that, when toluene is used as the intermediate phase and 3 μL of 0. 25 mol/L NaOH solution as the acceptor phase, the best microextraction efficiency is obtained after 50 min of extraction under a stirring rate of 800 r/min. The recovery of the tested urine samples is 76. 4% and the relative standard deviation is 3. 8% under the optimized microextraction condition.

  8. A Study of Method Development, Validation, and Forced Degradation for Simultaneous Quantification of Paracetamol and Ibuprofen in Pharmaceutical Dosage Form by RP-HPLC Method

    OpenAIRE

    Md. Sarowar Jahan; Md. Jahirul Islam; Rehana Begum; Ruhul Kayesh; Asma Rahman

    2014-01-01

    A rapid and stability-indicating reversed phase high-performance liquid chromatography (RP-HPLC) method was developed for simultaneous quantification of paracetamol and ibuprofen in their combined dosage form especially to get some more advantages over other methods already developed for this combination. The method was validated according to United States Pharmacopeia (USP) guideline with respect to accuracy, precision, specificity, linearity, solution stability, robustness, sensitivity, and...

  9. Toxicokinetics of the nerve agent (+/-)-VX in anesthetized and atropinized hairless guinea pigs and marmosets after intravenous and percutaneous administration.

    Science.gov (United States)

    van der Schans, Marcel J; Lander, Brenda J; van der Wiel, Herma; Langenberg, Jan P; Benschop, Hendrik P

    2003-08-15

    In continuation of our investigations on the toxicokinetics of the volatile nerve agents C(+/-)P(+/-)-soman and (+/-)-sarin, we now report on the toxicokinetics of the rather nonvolatile agent (+/-)-VX. A validated method was developed to determine blood levels of (+/-)-VX by means of achiral gas chromatography at blood levels > or =10 pg/ml. The ratio of the two enantiomers of VX in blood could be measured at levels > or =1 ng/ml by using chiral HPLC in combination with off-line gas chromatographic analysis. In order to obtain basic information on the toxicokinetics of (+/-)-VX, i.e., under conditions of 100% bioavailability, the blood levels of this agent were measured in hairless guinea pigs at iv doses corresponding with 1 and 2 LD50. The derived AUCs indicate a reasonable linearity of the toxicokinetics with dose. Also, the toxicokinetics in marmoset primates was studied at an absolute iv dose corresponding with 1 LD50 in the hairless guinea pig which led to approximately the same levels of (+/-)-VX in blood as observed at 2 LD50 in the hairless guinea pig. Finally, the toxicokinetics of (+/-)-VX were measured in hairless guinea pigs via the most relevant porte d' entrée for this agent, which is the percutaneous route at a dose corresponding with 1 LD50 (pc). Large variations were observed between individual animals in the rate of penetration of (+/-)-VX and in concomitant progression of AChE inhibition in blood of these animals. Blood levels of (+/-)-VX increased gradually over a 6-h period of time. After a 7-h penetration period, the total AUC corresponded with 2.5% bioavailability relative to iv administration. In contrast with the G-agents C(+/-)P(+/-)-soman and (+/-)-sarin, stereospecificity in the sequestration of the two enantiomers of (+/-)-VX is not a prominent phenomenon. It appears that (+/-)-VX is substantially more persistent in vivo than the two G-agents. This persistence may undermine the efficacy of pretreatment with carbamates of percutaneous

  10. Change Agent Survival Guide

    Science.gov (United States)

    Dunbar, Folwell L.

    2011-01-01

    Consulting is a rough racket. Only a tarantula hair above IRS agents, meter maids and used car sales people, the profession is a prickly burr for slings and arrows. Throw in education, focus on dysfunctional schools and call oneself a "change agent," and this bad rap all but disappears. Unfortunately, though, consulting/coaching/mentoring in…

  11. Agents in domestic environments

    NARCIS (Netherlands)

    Moergestel, Leo van; Langerak, Wouter; Meerstra, Glenn; Nieuwenburg, Niels van; Pape, Franc; Telgen, Daniël; Puik, Erik; Meyer, John-Jules

    2013-01-01

    Athor supplied : "This paper describes an agent-based architecture for domotics. This architecture is based on requirements about expandability and hardware independence. The heart of the system is a multi-agent system. This system is distributed over several platforms to open the possibility to ti

  12. 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

  13. 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: ...

  14. 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

    2015-08-13

    The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected.

  15. 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...

  16. 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

  17. 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.

  18. 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).

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

    Science.gov (United States)

    Tantawy, Mahmoud A; Hassan, Nagiba Y; Elragehy, Nariman A; Abdelkawy, Mohamed

    2013-03-01

    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 (D (1)) and derivative ratio (DD (1)) 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.

  20. Enantiomeric resolution of ibuprofen and flurbiprofen in human plasma by SPE-chiral HPLC methods.

    Science.gov (United States)

    Ali, Imran; Hussain, Iqbal; Saleem, Kishwar; Aboul-Enein, Hassan Y

    2012-07-01

    Chiral analysis of profens in human plasma is an important area of research due to different pharmaceutical activities of their enantiomers. The solid phase extraction of ibuprofen and flurbiprofen from human plasma was carried out on C18 cartridges by using phosphate buffer (50 mM, pH 6.0) followed by elution with methanol. Chiral-HPLC was performed on AmyCoat RP (150 mm x 46 mm, 3 μm particle size) column by using different combinations of water-acetonitrile-trifluoro acetic acid at 1.5 mLmin-1 flow rate. The detection was achieved at 236 and 254 nm for ibuprofen and flurbiprofen, respectively with 27±1°C as working temperature. The chromatographic parameters i.e. retention (k), separation (α) and resolution (Rs) factors ranged from 4.54-14.42, 1.10-1.30 and 1.01-1.49, respectively. The binding differences of enantiomers of ibuprofen and flurbiprofen were 4.4 and 5.2, respectively. These values suggest that S-(+)- enantiomer of flurbiprofen is more active than ibuprofen due to low enantiomeric difference of the later drug. The developed SPE-Chiral HPLC methods were validated, which are selective, efficient and reproducible.

  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. 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.

  3. 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

  4. 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.

  5. 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.

  6. 维生素D联合不同钙剂治疗婴幼儿佝偻病临床比较分析%Clinical Comparative Analysis of Vitamin D Combined with Different Calcium Agents in Treatment of Infantile Rachitis

    Institute of Scientific and Technical Information of China (English)

    车千红; 赵晴; 王福先

    2011-01-01

    目的 比较不同剂型维生素D与铁锌钙或单纯钙剂联合治疗婴幼儿佝偻病的临床疗效.方法 175例维生素D缺乏性佝偻病患儿随机分为大剂量维生素D3联合铁锌钙治疗组72例(Ⅰ)、大剂量维生素D3联合钙剂治疗组68例(Ⅱ)和小剂量维生素D2联合钙剂治疗组35例(Ⅲ),三组患儿治疗4、8周后进行疗效对比分析,治疗12周后比较三组血红蛋白浓度变化.结果 治疗4周后,Ⅰ组与Ⅱ组比较,治疗有效率差异无统计学意义(P>0.05);Ⅰ组与Ⅲ组比较,治疗有效率明显优于Ⅲ组,差异有统计学意义(P<0.05).治疗8周后,Ⅰ组有效率明显优于Ⅱ组、Ⅲ组,差异有统计学意义(P<0.05).治疗12周后,Ⅰ组平均血红蛋白浓度均明显高于Ⅲ组,差异有统计学意义(P<0.05).结论 婴幼儿佝偻病治疗初期应选用大剂量维生素D3联合铁锌钙治疗效果更佳,且长期铁锌钙合剂治疗不会造成血红蛋白浓度下降,宜作为婴幼儿佝偻病的首选治疗方法.%Objective To compare the clinical efficacy of different formulations of vitamin D and pure calcium or iron, zinc and calcium mixture combined treatment to infantile rachitis. Methods One hundred and seventy - five patients with vitamin D deficiency rachitis were divided into large- dose vitamin D3 combined iron, zinc and calcium mixture in the treatment group for 72 cases (I), large - dose vitamin D3 combined calcium in the treatment group for 68 cases (II) and small - dose vitamin D2 combined calcium in the treatment group for 35 cases (III). Take three groups of patients treated after 4 weeks, 8 weeks for the comparative analysis of efficacy. Compare the variation of hemoglobin concentration of three groups treated after 8 weeks. Results After 4 weeks of treatment, there was no statistically significant difference in the treatment efficiency compared group 1 with II (P >0.05). The efficiency of treatment in group 1 was obviously better than in group III

  7. 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

  8. New agents in HSC mobilization.

    Science.gov (United States)

    Domingues, Mélanie J; Nilsson, Susan K; Cao, Benjamin

    2017-02-01

    Mobilized peripheral blood (PB) is the most common source of hematopoietic stem cells (HSC) for autologous transplantation. Granulocyte colony stimulating factor (G-CSF) is the most commonly used mobilization agent, yet despite its widespread use, a considerable number of patients still fail to mobilize. Recently, a greater understanding of the interactions that regulate HSC homeostasis in the bone marrow (BM) microenvironment has enabled the development of new molecules that mobilize HSC through specific inhibition, modulation or perturbation of these interactions. AMD3100 (plerixafor), a small molecule that selectively inhibits the chemokine receptor CXCR4 is approved for mobilization in combination with G-CSF in patients with Non-Hodgkin's lymphoma and multiple myeloma. Nevertheless, identifying mobilization strategies that not only enhance HSC number, but are rapid and generate an optimal "mobilized product" for improved transplant outcomes remains an area of clinical importance. In recent times, new agents based on recombinant proteins, peptides and small molecules have been identified as potential candidates for therapeutic HSC mobilization. In this review, we describe the most recent developments in HSC mobilization agents and their potential impact in HSC transplantation.

  9. 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.

  10. An HPLC-UV method for determining plasma dimethylacetamide concentrations in patients receiving intravenous busulfan.

    Science.gov (United States)

    Cendana, Mildred; Lee, Samiuela; Upadhyay, Parth J; Byrne, Jennifer A; Shaw, Peter J; Earl, John; Nath, Christa E

    2016-12-07

    Dimethylacetamide (DMA) is a solvent used in the preparation of intravenous busulfan, an alkylating agent used in blood or marrow transplantation. DMA may contribute to hepatic toxicity, so it is important to monitor its clearance. The aim of this study was to develop an HPLC-UV assay for measurement of DMA in human plasma. After precipitation of plasma proteins with acetonitrile followed by dilution (1:4) with water, the extract was injected onto the HPLC and detected at 195 nm. Separation was performed using a Cogent-HPS 5 μm C18 column (250 × 4.6 mm) preceded by a Brownlee 7 μm RP18 , pre-column (1.5 cm × 3.2 mm). The mobile phase was 25 mm sodium phosphate buffer (pH 3), containing 2.5% (v/v) acetonitrile and 0.0005% (v/v) sodium-octyl-sulfonate. Using a flow rate of 1 mL/min, the retention times of DMA and the internal standard (IS), 2-chloroacetamide, were 9.5 and 3.5 min, respectively. Peak area ratio (DMA:IS) was a linear function of concentration from 1 to 1000 μg/mL. There was excellent intraday precision (<5% for 5-700 μg/mL DMA), accuracy (<3% deviation from the true concentration) and recovery (74-98%). The limits of detection and quantification were 1 and 5 μg/mL, respectively. In eight children who received intravenous busulfan, DMA concentrations ranged from 110 to 438 μg/mL.

  11. Determination of telaprevir in plasma of HCV-infected patients by HPLC-UV.

    Science.gov (United States)

    Tempestilli, Massimo; Milano, Elisa; D'Offizi, Gianpiero; Montalbano, Marzia; D'Avolio, Antonio; Gasperi, Tecla; Narciso, Pasquale; Ascenzi, Paolo; Pucillo, Leopoldo P

    2013-09-01

    Telaprevir is a direct acting antiviral agent, used with pegylated interferon and ribavirin for the management of chronic hepatitis C virus (HCV) genotype 1 infection, in patients not responding to therapy with pegylated interferon and ribavirin only. Although 75% of patients achieve a sustained virological response after treatment with telaprevir, adverse drug-drug interactions and undesirable events often occur. Therefore, telaprevir monitoring is pivotal to improve the management of HCV infection. Here, the first High-Performance Liquid Chromatography-Ultraviolet (HPLC-UV) method to quantify telaprevir in human plasma of HCV-genotype 1-infected patients is reported. The volume of the plasma sample was 700 μL. This method involved automated solid-phase extraction with Oasis HLB Cartridge 1 cc (divinylbenzene and N-vinylpyrrolidone). The extracted samples were reconstituted with 150 μL of 60/40 water/acetonitrile. Thirty microliters of these samples was injected into a HPLC-UV system, and the analytes were eluted on a X Terra(®) RP18 column (250 mm × 4.6 mm i.d.) with a particle size of 5 μm. The mobile phase (ammonium acetate buffer, 150 mM, pH 8.0, and methanol:acetonitrile 50:50) was delivered at 1.0 mL/min with linear gradient elution. The total run time for a single analysis was 16 min; telaprevir was detected by UV at 276 and 286 nm. The calibration curve was linear from 312.5 to 20,000 ng/mL (r(2) > 0.996). The absolute recovery of telaprevir ranged between 89 and 93% at concentrations of quality control samples of 800, 4,000, 8,000, and 16,000 ng/mL. Both precision and accuracy were always <15%. The HPLC-UV method reported here: (i) has been validated, (ii) is currently applied to monitor telaprevir in plasma of HCV-infected patients, and (iii) appears useful in a routine laboratory. ,

  12. 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.

  13. 局部晚期子宫颈鳞状细胞癌不同组合放化疗疗效的前瞻性比较研究%A randomized clinical trial in comparison of concurrent single agent cisplatin,cisplatin in combination with 5-fluorouracil and cisplatin in combination with taxel for locally advanced cervical squamous cell cancer

    Institute of Scientific and Technical Information of China (English)

    胡尔西旦·尼牙孜; 赵化荣; 忙尼沙·阿不都拉; 包永星

    2011-01-01

    目的 前瞻性比较3种不同化疗方案和根治性放射治疗的不同组合方式的同期放化疗疗效、不良反应及对生存的影响.方法 将261例ⅡB、ⅢA、ⅢB、ⅣA期的局部晚期宫颈鳞状细胞癌前瞻性随机分入3组:放疗加每周顺铂增敏化疗组(RT+DDP)、放疗加同期5-氟脲嘧啶和顺铂(RT+FC)化疗组、放疗加同期紫杉和顺铂(RT+TC)化疗组.放疗均是全程根治性放疗.放疗方法:盆腔外照射45~50 Gy,外照射30~40Gy时挡直肠区域;腔内高剂量率Iγ192后装治疗A点剂量25~36 Gy.RT+DDP组中每周顺铂30mg/m2、每周1次,共5~6次;RT+FC和RT+TC组中顺铂75mg/m2,分3 d静脉注射,RT+FC组每日缓慢静脉点滴5-氟脲嘧啶650 mg/m2,连用4 d;RT+TC组中紫杉醇135 mg/m2静脉点滴,两药联合化疗在每个患者的整个放疗中完成2周期.结果 完成计划的总病例数为261例,其中RT+DDP组88例、RT+FC组89例、RT+TC组84例.3组患者的一般临床特点差异无统计学意义.3组的总生存率差异、近期疗效、直肠和膀胱的3/4级晚期并发症发生率差异亦均无统计学意义(P>0.05);TC+RT组的无病生存率与DDP+RT组比较差异有统计学意义(P<0.017).结论 RT+DDP、RT+FC、RT+TC治疗局部晚期宫颈鳞状细胞癌疗效均可,患者均可耐受急性不良反应.RT+TC在无病生存方面可能使患者获益.%Objective To compare the outcome of the cisplatin-based chemotherapy with 5-fluoracil ( RT + FC), taxel ( RT + TC) two regimens concurrent chemo-radiotherapy with standard weekly single agent cisplatin and concurrent radiation therapy (RT + DDP). Methods Patients with locally advanced cervical squamous cell cancer of stage ⅡB, ⅡIA,ⅢB, and ⅣA with clinically negative aortic nodes were eligible. Pelvic RT dose was 45-50 Gy and high -dose rate intracavitary brachytherapy. The standard arm had weekly cisplatin 30 mg/m2 per week lasting 5-6 cycles during RT.The experimental arm had cisplatin 75 mg/m2/3wk

  14. Culturally Aware Agent Communication

    DEFF Research Database (Denmark)

    Rehm, Matthias; Nakano, Yukiko; Koda, Tomoko

    2012-01-01

    available for expressing not only task-relevant but also socially and psychologically relevant information makes it necessary to take influences into account that are not readily implemented like emotions or cultural heuristics. These influences have a huge impact on the success of an interaction......Agent based interaction in the form of Embodied Conversational Agents (ECAs) has matured over the last decade and agents have become more and more sophisticated in terms of their verbal and nonverbal behavior like facial expressions or gestures. Having such “natural” communication channels...

  15. 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.

  16. 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.

  17. 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.

  18. The observation of curative effect of combined with insulin therapy after failure treatment with oral hypoglycemic agents for type 2 diabetes%口服降糖药治疗2型糖尿病失效联合甘精胰岛素治疗疗效观察

    Institute of Scientific and Technical Information of China (English)

    熊东林

    2013-01-01

    目的:观察口服降糖药治疗2型糖尿病失效后,联合甘精胰岛素治疗糖尿病的疗效。方法筛选68例单用口服降糖药血糖控制不理想的2型糖尿病患者,睡前(2130)加用甘精胰岛素(来得时),治疗14周,比较前后空腹血糖(FPG)、餐后2h血糖(2hPG)、糖化血红蛋白(HbA1c)、空腹C肽、餐后2hC肽、体重变化及低血糖的发生。结果加用甘精胰岛素组治疗14周后,患者FPG、2hPG、HbA1c较治疗前明显下降(P<0.01),餐后2hC肽较治疗前明显升高(P<0.01),未见低血糖发生,体重指数影响不大。结论对单用口服药效果不佳的2型糖尿病,需及时加用甘精胰岛素治疗。%Objective To observe the curative effect of combined with insulin therapy after failure treatment with oral hypoglycemic agents for type 2 diabetes. Method Screening 68 cases with oral hypoglycemic agents alone with no ideal blood sugar control in type 2 diabetes, patients bedtime(9 30 pm) plus insulin glargine(Lantus) treatment with 14 weeks treatment, compared before and after FPG, 2hPG, HbA1c, fasting C peptide, 2h postprandial C-peptide, weight changes and the occurrence of low blood sugar. Results Combined with insulin treatment after 14 weeks , patients’s FPG, 2hPG, HbA1c significantly decreased than that before treatment(P<0.01), and with postprandial 2h C-peptide significantly higher(P<0.01). Conclusion It should be timely combined with insulin after failure treatment with oral hypoglycemic agents alone for type 2 diabetes.

  19. 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.

  20. 冷冻或外用药物联合光动力疗法治疗肛管内尖锐湿疣疗效观察%Observation of cryotherapy or externally applied agents combined with photodynamic therapy on treatment of condyloma acuminata in anal canal

    Institute of Scientific and Technical Information of China (English)

    李海燕; 程鸽; 刘凤娟; 韩靖; 翁文佳; 高艳青

    2014-01-01

    目的:观察局部冷冻或外用药物联合光动力治疗肛管内尖锐湿疣(CA)的疗效。方法采用局部冷冻或外用药物联合光动力治疗51例肛管内CA患者,光动力疗法7~10 d 治疗1次,共2~5次。于治疗结束后2、4、8、12周对疣体完全清除者进行随访,观察治疗情况。结果51例患者中47例疣体完全清除,疣体清除率为92.16%(47/51),其中41例痊愈,治愈率为87.23%(41/47)。随访疣体完全清除者中4例在治疗后8周复发,2例在12周内复发,复发率为12.77%(6/47)。结论局部冷冻或外用药物联合光动力治疗肛管内CA安全、有效。%Objective To observe the curative effect of cryotherapy or externally applied agents combined with photodynamic therapy in the treatment of anal canal condyloma acuminatum. Methods Fifty one patients who had condyloma acuminatum in anal canal were treated by cryotherapy or externally applied agents combined with photodynamic therapy, and the photodynamic therapy was given every 7 to 10 days, a total of 2 to 5 times. The patients who removed the verrucous body after the treatment were followed-up at 2, 4, 8, 12 weeks. Results Among the 51 cases, 47 cases’ verrucous body were completely removed, including recovery 41 cases. Follow-up the wart body completely removed patients, 4 cases relapsed in 8 weeks after treatment, 2 cases relapsed in 12 weeks. The wart body clearance rate was 92.16%(47/51), the cure rate was 87.23%(41/47), the recurrence rate was 12.76%(6/47). Conclusion Cryotherapy or externally applied agents combined with photodynamic therapy for the treatment of condyloma in anal canal is safe and effective.

  1. 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.

  2. A novel anti-alpha-fetoprotein single-chain variable fragment displays anti-tumor effects in HepG2 cells as a single agent or in combination with paclitaxel.

    Science.gov (United States)

    Ji, Xiaonan; Shen, Yanli; Sun, Hao; Gao, Xiangdong

    2016-08-01

    Human hepatocellular carcinoma (HCC) has a high rate of tumor recurrence and metastasis, resulting in shortened survival time. The function of alpha-fetoprotein (AFP) as a regulatory factor in the growth of HCC cells has been well defined. The aim of this study was to investigate the use of a novel AFP-specific single-chain variable fragment that blocked AFP and inhibited HCC cell growth. The results indicated that the anti-AFP single-chain variable fragment (scFv) induced growth inhibition of AFP-expressing HCC cell lines in vitro through induction of G1 cell cycle arrest and apoptosis. The mechanism of apoptosis probably involved with blocking AFP internalization and regulation of the PTEN/PI3K/Akt signaling network. Moreover, the anti-AFP-scFv also effectively sensitized the HepG2 cells to paclitaxel (PTX) at a lower concentration. The combination effect of PTX and anti-AFP-scFv displayed a synergistic effect on HepG2 cells both in vitro and in vivo. Our results demonstrated that targeting AFP by specific antibodies has potential immunotherapeutic efficacy in human HCC.

  3. 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.

  4. 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.

  5. Combined Pharmacologic Therapy in Postmenopausal Osteoporosis.

    Science.gov (United States)

    Shen, Yang; Gray, Dona L; Martinez, Dorothy S

    2017-03-01

    Antiresorptive agents for treating postmenopausal osteoporosis include selective estrogen receptor modulator (SERM), bisphosphonates and denoumab. Teriparatide is the only Food and Drug Administration-approved anabolic agent. Synergistic effects of combining teriparatide with an antiresorptive agent have been proposed and studied. This article reviews the trial designs and the outcomes of combination therapies. Results of the combination therapy for teriparatide and bisphosphonates were mixed; while small increases of bone density were observed in the combination therapy of teriparatide and estrogen/SERM and that of teriparatide and denosumab. Those clinical studies were limited by small sample sizes and lack of fracture outcomes.

  6. 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.

  7. Steroidal neuromuscular blocking agents

    NARCIS (Netherlands)

    Wierda, JMKH; Mori, K; Ohmura, A; Toyooka, H; Hatano, Y; Shingu, K; Fukuda, K

    1998-01-01

    Since 1964 approximately 20 steroidal neuromuscular blocking agents have been evaluated clinically. Pancuronium, a bisquaternary compound designed on the drawingboard, was the first steroidal relaxant introduced into clinical practice worldwide in the 1970's. Although a major improvement, pancuroniu

  8. 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...

  9. A Review on Method Development and Validation using HPLC

    Directory of Open Access Journals (Sweden)

    Rashmi Adhikari

    2016-09-01

    Full Text Available High performance liquid chromatography (HPLC is an analytical technique which is used to separate, detect and quantify various drugs and its related degradants. It is employed to separate manufactured drugs from drug related impurities, to detect and quantify synthesized drug and to reduce other impurities at the time of separation. A number of chromatographic parameters were evaluated in order to optimize the method. An appropriate mobile phase, column, column temperature, wavelength and gradient must be found that affords suitable compatibility and stability of drug as well as degradants and impurities. Validation of HPLC as per ICH guidelines covers all the performance characteristics of validation, likeaccuracy, precision, specificity, linearity, range, limit of detection, limit of quantification, robustness and system suitability testing.

  10. 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...

  11. Gradient Scouting in Reversed-Phase HPLC Revisited

    Science.gov (United States)

    Alcazar, A.; Jurado, J. M.; Gonzalez, A. G.

    2011-01-01

    Gradient scouting is the best way to decide the most suitable elution mode in reversed-phase high-performance liquid chromatography (RP-HPLC). A simple rule for this decision involves the evaluation of the ratio [delta]t/t[subscript G] (where [delta]t is the difference in the retention time between the last and the first peak and t[subscript G] is…

  12. 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......, and an acquisition time of 13 h resulted in spectra with adequate signal-to-noise ratios to detect all C-13 signals....

  13. 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.

  14. 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.

  15. Heterogeneity of caprine beta-casein elucidated by RP-HPLC/MS: genetic variants and phosphorylations.

    Science.gov (United States)

    Neveu, Carole; Mollé, Daniel; Moreno, Javier; Martin, Patrice; Léonil, Joëlle

    2002-11-01

    Casein variants occurring in milks from goats homozygous at the alpha(s1)-Cn locus were separated and identified by an RP-HPLC/ESI-MS method. Preferential haplotypes arose as well as some particularities in posttranslational modifications. A new variant of caprine beta-Cn, named C, as well as the phosphorylations pattern of the protein were characterized by the combined use of peptide mass fingerprinting and sequencing by tandem mass spectrometry. The molecular mass of the new variant in its 6P form was measured as 23854 Da and it differs in a mono amino acid substitution, A177 --> V177, from the variant A. The phosphorylation pattern of caprine beta-Cn is homologous to bovine beta-Cn concerning the 5P located on Ser15, 17, 18, 19, 35 but it presents a specific additional phosphorylation site on Thr12 that is comparable to human beta-Cn phosphorylation located on Thr3.

  16. 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

  17. Resonance Rayleigh scattering for detection of proteins in HPLC.

    Science.gov (United States)

    Lu, Xin; Luo, Zhihui; Liu, Chengwei; Zhao, Shulin

    2008-09-01

    An HPLC-resonance Rayleigh scattering (RRS) (HPLC-RRS) detection system is described for separation and detection of proteins. This system is based on the modification of a commercial HPLC instrument involving the addition of a pump and a T-shaped interface, and a common fluorescence detector was used for detection. The detection principle is based on the change of RRS intensity of the ion-association complex formed from biebrich scarlet (BS) and protein. The RRS signal was detected at lambdaex=lambdaem=376 nm. The utility of the presented method was demonstrated by the separation and determination of four proteins involving cytochrome (Cyt-c), lysozyme (Lys), HSA, and gamma-globulin (gamma-Glo). An LOD of 0.2-1.0 microg/mL was reached and a linear range was found between peak area and concentration in the range of 0.20-3.0 microg/mL for Cyt-c, 0.25-2.5 microg/mL for Lys, 1.5-10 microg/mL for HSA, and 2.0-15 microg/mL for gamma-Glo, with linear regression coefficients all above 0.99. The method presented has been applied to determine HSA and gamma-Glo in human serum samples synchronously.

  18. 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.

  19. 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

  20. 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.

  1. Toxicity in Sensitive Period to Teratogenic Agent of Artemisinin-piperaquine Combination in Rats%青蒿素哌喹复方对大鼠致畸敏感期毒性试验

    Institute of Scientific and Technical Information of China (English)

    万红平; 梁礼珍; 蔡五妹; 张宏涛; 卢琦华

    2008-01-01

    背景与目的:青蒿素哌喹复方(artemisinin-pipemquine combination,ATQ)是由青蒿素与哌喹组成的抗疟复方,本研究观察其对大鼠母体及胎仔的影响.材料与方法:将SD孕鼠随机分为6组,每组18只.设ATQ 35、70、120、200 ms/(ks·d)4个剂量组,另设溶剂对照和环磷酰胺阳性药物对照组.大鼠妊娠7~17d每天灌胃ATQ 1次,妊娠20 d处死,检查各项指标.结果:ATQ70 mg/(ks·d)及以上剂量延缓大鼠胎仔发育,胎仔体重及身长低于溶剂对照组(P0<0.01);ATQ 120 ms/(ks·d)和200 mg/(ks·d)剂量对大鼠胎仔有致死毒性,胚胎着床后损失率分别为25.5%和38.8%,高于溶剂对照组(P<0.01);ATQ 120 mg/(ks·d)和200 mg/(ks·d)剂量组出现胎仔骨骼畸形,主要表现为肋骨隆突、缺失、骨化不全及短多肋(14肋)等;ATQ 35 mg/(ks·d)剂量对母鼠及胎仔发育未表现出毒性.结论:ATQ对SD大鼠具有发育毒性;在本实验条件下,35 mg/(ks·d)剂量为孕鼠的最大安全剂量.

  2. 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.

  3. 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)

    Janssen, H.-G.; Swindells, C.; Gunning, P.; Wang, W.; Grün, C.; Mahabir, K.; Maharaj, V.J.; Apps, P.J.

    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

  4. Combination strategies for pain management.

    Science.gov (United States)

    Raffa, Robert B; Clark-Vetri, Rachel; Tallarida, Ronald J; Wertheimer, Albert I

    2003-10-01

    At least two factors relating to pain management using oral analgesics suggest that combination strategies merit consideration: many pains arise from more than one physiological cause and current analgesics have adverse effect profiles that might be reduced by combination with another agent in smaller doses or with less frequent dosing. In addition to increased convenience, combinations sometimes also result in the unexpected benefit of synergy. But not all pains, clinical settings or combinations merit the extra expense or other potential negative features of fixed-ratio products. This review examines the multiple basic science, clinical and pharmacoeconomic issues relating to analgesic combinations and the methodologies available for assessing these issues.

  5. 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.

  6. HPLC FOR CONTROL STABILITY OF QUERCETIN INJECTABLE DOSAGE FORM

    Directory of Open Access Journals (Sweden)

    Martynov AV

    2016-12-01

    Full Text Available Introduction. Quercetin is a flavone derivatives which known like a substances with vitamin activity, high antioxidant, antimutagenic and anticarcinogenic activity and many other types of biological activity. Wide usage of quercetin prevents their polyphenolic nature structure which does not allow a high bioavailability of pure quercetin when administered orally. This is associated with a wide spectrum variety of chemical reactions for the phenolic groups: from interaction with amino acid residues in proteins to reactions with amine heterocyclic alkaloids and polysaccharides. In our days Corvitin – one from the number of quercetin based drugs with sufficiently low levels all types toxicity, allergenic and has no irritating action on intravenous administration. In the same time quercetin cannot be used in full measure because of the limited number of publications with analysis methods, especially HPLC. Determining the stability over time of concentrate quercetin solution, as well as determining the stability of the concentrate to the original autoclave sterilization conditions is a promising direction in creating new drugs. Materials and methods The objective was to research quercetin soluble formulation samples in different conditions: 1 fresh dilute concentrate (0.9% sodium chloride; 2 the original dilute concentrate, which was stored at room temperature for 14 days in light and 3 similar to the first sample dilute concentrate, which went before breeding in autoclaving at 120 0 C for 20 minutes. The objects used in the studies were industrial drug-substance quercetin (Sinkea manufactured (China, the original pharmaceutical composition as the soluble form of quercetin for injection and aerosol applications, glycerol (Sigma, Polysorbat 80 (Merk, ethanol 96 %. For the HPLC – analysis, chromatograph "Milichrom A-02" (SiChrom, Knauer (Econova, Novosibirsk, Russia was used. Results and discussion Quercetin was identified using information on its

  7. Effect observation of swallowing therapy instrument combined with enteral nutrition agent on dysphagia after stroke%吞咽治疗仪联合肠内营养剂治疗卒中后吞咽障碍的疗效观察

    Institute of Scientific and Technical Information of China (English)

    田向阳; 赵卫东; 倪贵华; 杨梅

    2011-01-01

    目的 观察吞咽治疗仪联合肠内营养剂治疗对卒中后吞咽障碍的疗效.方法 将96例脑卒中后吞咽障碍的患者随机分为对照组、吞咽治疗仪组、肠内营养剂组及联合治疗组.各组均给予脑卒中常规药物治疗及鼻饲流质饮食;在此基础上,吞咽治疗仪组辅以吞咽治疗仪治疗,肠内营养剂组添加肠内营养制剂,联合治疗组同时辅以吞咽治疗仪治疗及添加肠内营制剂.分别于治疗前、治疗15 d后应用饮水试验及吞咽困难量表对患者吞咽功能评分,并评价疗效.结果 治疗15 d后各组饮水试验及吞咽困难量表评分较治疗前明显改善(均P<0.01),改善程度依次为联合治疗组、吞咽治疗仪组、肠内营养剂组、对照组;各组间评分差异有统计学意义(均P<0.05).各组总有效率分别为91.7%、79.2%~83.3%、66.7% ~ 70.8%及50%;联合治疗组显著高于其他3组(均P<0.01);其他3组间总有效率的差异有统计学意义(均P<0.05).结论 吞咽治疗仪联合肠内营养治疗对脑卒中后吞咽障碍患者的康复具有协同效应.%Objective To observe the effectiveness of swallowing therapy instrument combined with enteral nutrition agent on dysphagia after stroke. Methods Ninety-six patients with dysphagia after stroke were randomly divided into the control group, swallowing therapy instrument group, enteral nutrition gent group and combination therapy group. All the patients were treated with routine therapy of stroke, and liquid diet was nasal feeded. In addition, the swallowing therapy instrument group and enteral nutrition agent group were given appropriate treatment, respectively; and the combination therapy group was given swallowing therapy instrument combined with enteral nutrition agent. Repetitive water drinking test and dysphagia scale were used before and 15 d after treatment to evaluate swallowing function and the efficacy. Results After treatment, the

  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. 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...

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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…

  15. 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

  16. 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.

  17. Developing Enculturated Agents

    DEFF Research Database (Denmark)

    Rehm, Matthias

    2010-01-01

    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...... 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...

  18. Formulation factors affecting the isomerization rate of betamethasone-17-valerate in a developmental hydrophilic cream - a HPLC and microscopy based stability study.

    Science.gov (United States)

    Byrne, Jonathan; Wyraz, Anke; Velasco-Torrijos, Trinidad; Reinhardt, Robert

    2016-02-19

    The formulation of betamethasone-17-valerate (BV) into topical medicines presents a significant challenge for the formulation chemist. The substance is susceptible to acid and base catalyzed isomerization in aqueous environments, which results in valerate transesterification from carbon 17 to carbon 21 of the steroid ring system. This acyl migration process is of significant clinical importance since the 21-valerate ester possesses only a fraction of the potency of the 17-valerate parent compound. Isomerization of BV should therefore be reduced to a minimum through design of a suitable drug vehicle. In this study, the effect of varying the concentration of several excipient components on the isomerization rate of betamethasone valerate in a model hydrophilic cream has been investigated. These excipients include the emulsifier macrogolstearylether-20/21, the co-emulsifier cetylstearyl alcohol and the thickening agent hydroxyl propyl methylcellulose. Additionally, the influence of pH, the presence of the antioxidant, alpha-tocopherol, as well as the chelating agent, disodium edetate, on the stability of the formulation have been investigated. Trial drug product formulations, which were designed to investigate the influence of the above-mentioned components/parameters were manufactured and their stability was tested according to current ICH Guidelines. The content, purity and crystalline structure of the active substance in these formulations was analyzed by a combination of HPLC and microscopy techniques. The study demonstrates that the rate of isomerization of betamethasone valerate depends significantly on the concentration of emulsifier used in the cream formulation. At higher concentrations of emulsifier the isomerization proceeds rapidly with significant degradation over a period of weeks, whereas at lower concentrations significant degradation may not be observed, even after several years' storage. The influence of the emulsifier has been shown to be

  19. Agent Persuasion Mechanism of Acquaintance

    Science.gov (United States)

    Jinghua, Wu; Wenguang, Lu; Hailiang, Meng

    Agent persuasion can improve negotiation efficiency in dynamic environment based on its initiative and autonomy, and etc., which is being affected much more by acquaintance. Classification of acquaintance on agent persuasion is illustrated, and the agent persuasion model of acquaintance is also illustrated. Then the concept of agent persuasion degree of acquaintance is given. Finally, relative interactive mechanism is elaborated.

  20. 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....

  1. HPLC-MS/MS methods for the determination of 52 perfluoroalkyl and polyfluoroalkyl substances in aqueous samples.

    Science.gov (United States)

    Gremmel, Christoph; Frömel, Tobias; Knepper, Thomas P

    2017-02-01

    Two quantitative methods using high-performance liquid chromatography (HPLC) combined with triple quadrupole tandem mass spectrometry (MS/MS) were developed to determine perfluoroalkyl and polyfluoroalkyl substances (PFASs) in aqueous samples. The first HPLC-MS/MS method was applied to 47 PFASs of 12 different substance classes with acidic characteristics such as perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkane sulfonic acids (PFSAs), as well as precursor substances and biotransformation intermediates (e.g., unsaturated fluorotelomer carboxylic acids). In addition, 25 (13)C-, (18)O-, and (2)H-labeled PFASs were used as internal standards in this method. The second HPLC-MS/MS method was applied to fluorotelomer alcohols (FTOHs) and perfluorooctane sulfonamidoethanols as these compounds have physicochemical properties different from those of the previous ones. Accuracy between 82% and 110% and a standard deviation in the range from 2% to 22% depending on the substances were determined during the evaluation of repeatability and precision. The method quantification limit after solid-phase extraction ranged from 0.3 to 199 ng/L depending on the analyte and matrix. The HPLC-MS/MS methods developed were suitable for the determination of PFASs in aqueous samples (e.g., wastewater treatment plant effluents or influents after solid-phase extraction). These methods will be helpful in monitoring campaigns to evaluate the relevance of precursor substances as indirect sources of perfluorinated substances in the environment. In one exemplary application in an industrial wastewater treatment plant, FTOHs were found to be the major substance class in the influent; in particular, 6:2-FTOH was the predominant compound in the industrial samples and accounted for 74% of the total PFAS concentration. The increase in the concentration of the transformation products of FTOHs in the corresponding effluent, such as fluorotelomer carboxylic acids, unsaturated fluorotelomer

  2. Development and Validation of a Precise, Single HPLC Method for the Determination of Tolperisone Impurities in API and Pharmaceutical Dosage Forms

    OpenAIRE

    RAJU, Thummala; Seshadri, Raja; Arutla, Srinivas; MOHAN, Tharlapu; RAO, Ivaturi; NITTALA, Someswara

    2012-01-01

    A novel, sensitive, stability-indicating HPLC method has been developed for the quantitative estimation of Tolperisone-related impurities in both bulk drugs and pharmaceutical dosage forms. Effective chromatographic separation was achieved on a C18 stationary phase with a simple mobile phase combination delivered in a simple gradient programme, and quantitation was by ultraviolet detection at 254 nm. The mobile phase consisted of a buffer and acetonitrile delivered at a flow rate 1.0 ml/min. ...

  3. An HPLC-tandem mass spectrometry method for simultaneous detection of alkylated base excision repair products.

    Science.gov (United States)

    Mullins, Elwood A; Rubinson, Emily H; Pereira, Kevin N; Calcutt, M Wade; Christov, Plamen P; Eichman, Brandt F

    2013-11-01

    DNA glycosylases excise a broad spectrum of alkylated, oxidized, and deaminated nucleobases from DNA as the initial step in base excision repair. Substrate specificity and base excision activity are typically characterized by monitoring the release of modified nucleobases either from a genomic DNA substrate that has been treated with a modifying agent or from a synthetic oligonucleotide containing a defined lesion of interest. Detection of nucleobases from genomic DNA has traditionally involved HPLC separation and scintillation detection of radiolabeled nucleobases, which in the case of alkylation adducts can be laborious and costly. Here, we describe a mass spectrometry method to simultaneously detect and quantify multiple alkylpurine adducts released from genomic DNA that has been treated with N-methyl-N-nitrosourea (MNU). We illustrate the utility of this method by monitoring the excision of N3-methyladenine (3 mA) and N7-methylguanine (7 mG) by a panel of previously characterized prokaryotic and eukaryotic alkylpurine DNA glycosylases, enabling a comparison of substrate specificity and enzyme activity by various methods. Detailed protocols for these methods, along with preparation of genomic and oligonucleotide alkyl-DNA substrates, are also described.

  4. 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%.

  5. 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.

  6. 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.

  7. Simultaneous determination of clobazam and its major metabolite in human plasma by a rapid HPLC method.

    Science.gov (United States)

    Rouini, Mohammadreza; Ardakani, Yalda H; Hakemi, Lida; Mokhberi, Maryam; Badri, Gheise

    2005-09-05

    A rapid and specific HPLC method has been developed and validated for simultaneous determination of clobazam, the anticonvulsant agent, and its major metabolite in human plasma. The sample preparation was a liquid-liquid extraction with tuloene yielding almost near 100% recoveries of two compounds. Chromatographic separation was achieved with a Chromolith Performance RP-18e 100 mm x 4.6mm column, using a mixture of a phosphate buffer (pH 3.5; 10mM)-acetonitrile (70:30, v/v), in isocratic mode at 2 ml/min at a detection wave-length of 228 nm. The calibration curves were linear (r(2)>0.998) in the concentration range of 5-450 ng ml(-1). The lower limit of quantification was 5 ng ml(-1) for two compounds studied. The within- and between-day precisions in the measurement of QC samples at four tested concentrations were in the range of 0.89-9.1% and 2.1-10.1% R.S.D., respectively. The developed procedure was applied to assess the pharmacokinetics of clobazam and its major metabolite following administration of a single 10mg oral dose of clobazam to healthy volunteers.

  8. 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...

  9. 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...

  10. 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

  11. Remote Agent Experiment

    Science.gov (United States)

    Benard, Doug; Dorais, Gregory A.; Gamble, Ed; Kanefsky, Bob; Kurien, James; Millar, William; Muscettola, Nicola; Nayak, Pandu; Rouquette, Nicolas; Rajan, Kanna; Norvig, Peter (Technical Monitor)

    2000-01-01

    Remote Agent (RA) is a model-based, reusable artificial intelligence (At) software system that enables goal-based spacecraft commanding and robust fault recovery. RA was flight validated during an experiment on board of DS1 between May 17th and May 21th, 1999.

  12. Determination of Trace Level of cAMP in Locusta Migratoria Manilensis Meyen by HPLC with Fluorescence Derivation

    Directory of Open Access Journals (Sweden)

    Canping Pan

    2006-08-01

    Full Text Available A sensitive and rapid method was developed for the determination of cAMP inLocusta migratoria manilensis Meyen by high-performance liquid chromatography withfluorescence detection. The cAMP was derivatized using chloroacetaldehyde and TBASbuffer/methanol was used as the mobile phase. A detection quantification of 40 fmol/mlcould be achieved when using fluorescence detection. An HPLC-MS method using DMHAas an ion-pair agent to analyze cAMP was also demonstrated. We studied the effect ofdopamine and other stimulants on cAMP levels from isolated locust central nervoussystems. The new method is well suited for the analysis of cAMP in small biologicalsamples.

  13. 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.

  14. Determination of Selected Colored Smokes on Glass Fiber Discs by High Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    1991-05-01

    High Performance Liquid Chromatography (HPLC) 12. PERSONAL AUTHOR(S) F F_ n.ipl’prifl. Alan R...GROUP SUB-GROUP High Performance Liquid Chromatography (HPLC), Analytical IMethod, 1,4-diamino-2,3-dihydroanthraquinone, 2-(2 - _ quinolinyl)-1,3...weights, low vapor pressures and low thermal stability. High performance liquid chromatography (HPLC) appears to be the analytical method of choice

  15. Separation of antifungal chiral drugs by SFC and HPLC: a comparative study.

    Science.gov (United States)

    Bernal, J L; Toribio, L; del Nozal, M J; Nieto, E M; Montequi, M I

    2002-12-31

    The enantiomeric separation of several compounds, including an antifungal drug and several of its precursors, using HPLC and SFC is described in this work. The columns employed were based on polysaccharide derivatives and the results show that most of the separations obtained by SFC are better, in terms of high resolution and short analysis time, than those obtained by HPLC. Only one compound could not be resolved using SFC but, in this case, HPLC provided baseline resolution.

  16. 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.

  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. Hydrophobicity measurements by HPLC: A new approach to. pi. constants

    Energy Technology Data Exchange (ETDEWEB)

    Gago, F.; Alvarez-Builla, J.; Elguero, J.

    1987-01-01

    A classical HPLC method of measuring log P/sub o/w/ has been reevaluated and applied to 107 different mono- and disubstituted benzenes. The contribution of several functional groups has been estimated through multiple regression analysis, obtaining statistically significant mean ..pi../sup *//sub m/ values. Deviations of experimentally determined log P/sup */ values for a set of ortho-, meta-, and para- disubstituted isomers from the ''simple additive'' model have been evaluated, and interpretations are suggested.

  19. HPLC-Diode Array Detector Fingerprints of Various Mentha Species.

    Science.gov (United States)

    Hawrył, Mirosław A

    2014-01-01

    Gradient elution HPLC was applied to develop fingerprints of 12 extracts obtained from selected mint species. The gradient was optimized by use of Merck ChromSword computer software on the basis of retention data of some standard compounds occurring in the investigated plant material. Two column types (RP18 and pentafluorophenyl) and two mobile phases (methanol-water and acetonitrile-water) were used during the experiments. Fingerprints of all extracts were generated, and on the basis of the fingerprints identification of the mints was possible.

  20. Agent-Based Cloud Computing

    OpenAIRE

    Sim, Kwang Mong

    2012-01-01

    Agent-based cloud computing is concerned with the design and development of software agents for bolstering cloud service\\ud discovery, service negotiation, and service composition. The significance of this work is introducing an agent-based paradigm for\\ud constructing software tools and testbeds for cloud resource management. The novel contributions of this work include: 1) developing\\ud Cloudle: an agent-based search engine for cloud service discovery, 2) showing that agent-based negotiatio...