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Denis Mulleman - One of the best experts on this subject based on the ideXlab platform.

Yanping Shi - One of the best experts on this subject based on the ideXlab platform.

  • uplc ms ms analysis for antioxidant components of lycii fructus based on spectrum Effect Relationship
    Talanta, 2018
    Co-Authors: Xianfei Zhang, Juan Chen, Junli Yang, Yanping Shi
    Abstract:

    Lycii Fructus is widely cultivated in the Northwest China. It is well-known for its antiaging Effect in traditional Chinese medicines (TCMs), but the Effective components are not clear. In this work, the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was used to study the antioxidant components of Lycii Fructus through analyzing the spectrum-Effect Relationship, and the positive correlation components with antioxidant activity were partially identified. The extractums of Lycii Fructus were adsorbed with macroporous resin, and then eluted with water and 30%, 60%, 90% ethanol in turn. The extract fraction eluted with 60% ethanol was determined as the best, and was taken for subsequent experiments. With the above separation method, UPLC fingerprints of thirty batches of Lycii Fructus (from different areas) were obtained, and thirty common peaks were selected through similarity analysis (SA). Combined with the data of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays, the spectrum-Effect Relationship was studied. The results showed that the main peaks with antioxidant activity were P14, P26, P8, and P21 for DPPH, and P26, P14, P21, and P19 for ABTS. Using the UPLC-MS/MS data, peaks P14, P19, P21, and P30 were respectively identified as chlorogenic acid, quercetin, kaempferol, and isorhamnetin, and then the results were confirmed through comparison with the standards and other references. Finally, their strong antioxidant activities were validated experimentally.

David Ternant - One of the best experts on this subject based on the ideXlab platform.

  • Pharmacokinetics and concentration–Effect Relationship of adalimumab in rheumatoid arthritis
    British Journal of Clinical Pharmacology, 2015
    Co-Authors: David Ternant, Emilie Ducourau, Piéra Fuzibet, Céline Vignault, Xavier Le Loët, Olivier Vittecoq, Thierry Lequerre, Philippe Goupille, Herve Watier, Denis Mulleman
    Abstract:

    Aims This study aimed at describing adalimumab pharmacokinetics (PK) and the concentration–Effect Relationship of adalimumab using pharmacokinetic–pharmacodynamic (PK–PD) modelling in patients with rheumatoid arthritis (RA).

  • Pharmacokinetics and concentration-Effect Relationship of adalimumab in rheumatoid arthritis.
    British journal of clinical pharmacology, 2015
    Co-Authors: David Ternant, Emilie Ducourau, Piéra Fuzibet, Céline Vignault, Xavier Le Loët, Olivier Vittecoq, Thierry Lequerre, Philippe Goupille, Herve Watier, Denis Mulleman
    Abstract:

    Aims This study aimed at describing adalimumab pharmacokinetics (PK) and the concentration–Effect Relationship of adalimumab using pharmacokinetic–pharmacodynamic (PK–PD) modelling in patients with rheumatoid arthritis (RA).

  • Interindividual variability in the concentration–Effect Relationship of antilymphocyte globulins—a possible influence of FcγRIIIa genetic polymorphism
    British Journal of Clinical Pharmacology, 2007
    Co-Authors: David Ternant, Maud Beneton, Marc Ohresser, Guy Touchard, Gunnar Alvan, Matthias Büchler, Bruno Hurault De Ligny, Olivier Toupance, Herve Watier, Yvon Lebranchu
    Abstract:

    WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • There is interindividual variability in the antilymphocyte globulin (ALG) Effect, but there is no pharmacokinetic–pharmacodynamic study of this subject. • In addition, a time dependence of the pharmacokinetics of some therapeutic antibodies has been described. • ALGs may partly act by antibody-dependent cellular cytotoxicity (ADCC), but their mechanism of action in humans is not known. WHAT THIS STUDY ADDS • Horse ALG pharmacokinetics can be described using a two-compartment model with time-dependent central volume of distribution. • After an initial concentration-independent lymphocyte depletion, the concentration–Effect Relationship can be described using a physiological indirect response model. • The genetic polymorphism of FcγRIIIa at position 158 may influence the ALG concentration–Effect Relationship and these polyclonal antibodies may therefore act by ADCC. AIMS Polyclonal antilymphocyte globulins (ALGs) are currently used in transplantation, but the sources of interindividual variability of their Effect are poorly understood. No pharmacokinetic–pharmacodynamic (PK–PD) study of ALG is available. Moreover, the genetic polymorphism of FcγRIIIa, a receptor for the Fc portion of immunoglobulins involved in antibody-dependent cellular cytotoxicity (ADCC), may influence their concentration–Effect Relationship. METHODS Fourteen kidney transplant patients treated by horse ALG were included in a prospective, noncomparative study. A population two-compartment PK model including a time dependence of the central volume of distribution was developed. Total lymphocyte count was used as biomarker of Effect. Concentration–Effect data were described using a physiological indirect response model, combining concentration-dependent and -independent inhibitions of lymphocyte input into the circulation. In addition, six kidney transplant patients in whom ALG concentrations were not available were included retrospectively. All patients were genotyped for FCGR3A. RESULTS Both the PK and the PK–PD model described the data satisfactorily and showed high interindividual variability. Asymptotic T1/2-α and T1/2-β-values were 1.3 and 25 days, respectively. The concentration of ALG leading to a 50% inhibition of lymphocyte input (IC50) was lower in FCGR3A-V carriers than in FCGR3A-F/F patients (383 ± 199 vs. 593 ± 209 mg l−1, P = 0.008). CONCLUSIONS This is the first description of the ALG Effect on lymphocyte count using PK–PD modelling. Our results show that part of the variability in their concentration–Effect Relationship may be explained by FcγRIIIa genetic polymorphism and therefore that horse ALG may deplete lymphocytes by ADCC.

Herve Watier - One of the best experts on this subject based on the ideXlab platform.

  • Pharmacokinetics and concentration–Effect Relationship of adalimumab in rheumatoid arthritis
    British Journal of Clinical Pharmacology, 2015
    Co-Authors: David Ternant, Emilie Ducourau, Piéra Fuzibet, Céline Vignault, Xavier Le Loët, Olivier Vittecoq, Thierry Lequerre, Philippe Goupille, Herve Watier, Denis Mulleman
    Abstract:

    Aims This study aimed at describing adalimumab pharmacokinetics (PK) and the concentration–Effect Relationship of adalimumab using pharmacokinetic–pharmacodynamic (PK–PD) modelling in patients with rheumatoid arthritis (RA).

  • Pharmacokinetics and concentration-Effect Relationship of adalimumab in rheumatoid arthritis.
    British journal of clinical pharmacology, 2015
    Co-Authors: David Ternant, Emilie Ducourau, Piéra Fuzibet, Céline Vignault, Xavier Le Loët, Olivier Vittecoq, Thierry Lequerre, Philippe Goupille, Herve Watier, Denis Mulleman
    Abstract:

    Aims This study aimed at describing adalimumab pharmacokinetics (PK) and the concentration–Effect Relationship of adalimumab using pharmacokinetic–pharmacodynamic (PK–PD) modelling in patients with rheumatoid arthritis (RA).

  • Interindividual variability in the concentration–Effect Relationship of antilymphocyte globulins—a possible influence of FcγRIIIa genetic polymorphism
    British Journal of Clinical Pharmacology, 2007
    Co-Authors: David Ternant, Maud Beneton, Marc Ohresser, Guy Touchard, Gunnar Alvan, Matthias Büchler, Bruno Hurault De Ligny, Olivier Toupance, Herve Watier, Yvon Lebranchu
    Abstract:

    WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • There is interindividual variability in the antilymphocyte globulin (ALG) Effect, but there is no pharmacokinetic–pharmacodynamic study of this subject. • In addition, a time dependence of the pharmacokinetics of some therapeutic antibodies has been described. • ALGs may partly act by antibody-dependent cellular cytotoxicity (ADCC), but their mechanism of action in humans is not known. WHAT THIS STUDY ADDS • Horse ALG pharmacokinetics can be described using a two-compartment model with time-dependent central volume of distribution. • After an initial concentration-independent lymphocyte depletion, the concentration–Effect Relationship can be described using a physiological indirect response model. • The genetic polymorphism of FcγRIIIa at position 158 may influence the ALG concentration–Effect Relationship and these polyclonal antibodies may therefore act by ADCC. AIMS Polyclonal antilymphocyte globulins (ALGs) are currently used in transplantation, but the sources of interindividual variability of their Effect are poorly understood. No pharmacokinetic–pharmacodynamic (PK–PD) study of ALG is available. Moreover, the genetic polymorphism of FcγRIIIa, a receptor for the Fc portion of immunoglobulins involved in antibody-dependent cellular cytotoxicity (ADCC), may influence their concentration–Effect Relationship. METHODS Fourteen kidney transplant patients treated by horse ALG were included in a prospective, noncomparative study. A population two-compartment PK model including a time dependence of the central volume of distribution was developed. Total lymphocyte count was used as biomarker of Effect. Concentration–Effect data were described using a physiological indirect response model, combining concentration-dependent and -independent inhibitions of lymphocyte input into the circulation. In addition, six kidney transplant patients in whom ALG concentrations were not available were included retrospectively. All patients were genotyped for FCGR3A. RESULTS Both the PK and the PK–PD model described the data satisfactorily and showed high interindividual variability. Asymptotic T1/2-α and T1/2-β-values were 1.3 and 25 days, respectively. The concentration of ALG leading to a 50% inhibition of lymphocyte input (IC50) was lower in FCGR3A-V carriers than in FCGR3A-F/F patients (383 ± 199 vs. 593 ± 209 mg l−1, P = 0.008). CONCLUSIONS This is the first description of the ALG Effect on lymphocyte count using PK–PD modelling. Our results show that part of the variability in their concentration–Effect Relationship may be explained by FcγRIIIa genetic polymorphism and therefore that horse ALG may deplete lymphocytes by ADCC.

Xianfei Zhang - One of the best experts on this subject based on the ideXlab platform.

  • uplc ms ms analysis for antioxidant components of lycii fructus based on spectrum Effect Relationship
    Talanta, 2018
    Co-Authors: Xianfei Zhang, Juan Chen, Junli Yang, Yanping Shi
    Abstract:

    Lycii Fructus is widely cultivated in the Northwest China. It is well-known for its antiaging Effect in traditional Chinese medicines (TCMs), but the Effective components are not clear. In this work, the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was used to study the antioxidant components of Lycii Fructus through analyzing the spectrum-Effect Relationship, and the positive correlation components with antioxidant activity were partially identified. The extractums of Lycii Fructus were adsorbed with macroporous resin, and then eluted with water and 30%, 60%, 90% ethanol in turn. The extract fraction eluted with 60% ethanol was determined as the best, and was taken for subsequent experiments. With the above separation method, UPLC fingerprints of thirty batches of Lycii Fructus (from different areas) were obtained, and thirty common peaks were selected through similarity analysis (SA). Combined with the data of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays, the spectrum-Effect Relationship was studied. The results showed that the main peaks with antioxidant activity were P14, P26, P8, and P21 for DPPH, and P26, P14, P21, and P19 for ABTS. Using the UPLC-MS/MS data, peaks P14, P19, P21, and P30 were respectively identified as chlorogenic acid, quercetin, kaempferol, and isorhamnetin, and then the results were confirmed through comparison with the standards and other references. Finally, their strong antioxidant activities were validated experimentally.