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Haixue Kuang - One of the best experts on this subject based on the ideXlab platform.

  • simultaneous determination of Aesculin aesculetin fraxetin fraxin and polydatin in beagle dog plasma by uplc esi ms ms and its application in a pharmacokinetic study after oral administration extracts of ledum palustre l
    Molecules, 2018
    Co-Authors: Zhibin Wang, Haixue Kuang, Wenbo Zhu, Hua Liu, Mengmeng Song, Bingyou Yang, Deqiang Yang, Qiuhong Wang
    Abstract:

    A rapid, simple and sensitive ultra-performance liquid chromatography-electrospray-ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for the simultaneous determination of Aesculin, aesculetin, fraxetin, fraxin and polydatin in beagle dog plasma for the first time. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 mm × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.4 mL/min, using a mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). The analytes and IS were detected by multiple reaction monitoring (MRM) via negative ion mode with ion transitions of m/z 339.1⁻m/z 176.8 for Aesculin, m/z 176.8⁻m/z 88.9 for aesculetin, m/z 206.8⁻m/z 192.1 for fraxetin, m/z 369.1⁻m/z 206.9 for fraxin, m/z 389.1⁻m/z 227.0 for polydatin and m/z 415.2⁻m/z 295.1 for puerarin. This method was validated according to the FDA guidelines and the results met the requirements of analysis. The calibration curves of analytes were linear with correlation coefficients more than 0.9980. The intra- and inter-day precisions were less than 15% and the accuracy was within ±15%. The maximum plasma concentration (Cmax) of Aesculin, aesculetin, fraxetin, fraxin and polydatin was 46.75 ± 7.46, 209.9 ± 57.65, 369.7 ± 48.87, 67.04 ± 12.09 and 47.14 ± 12.04 ng/mL, respectively. The time to reach the maximum plasma concentration (Tmax) was 1.32 ± 0.38 h for Aesculin, 1.03 ± 0.27 h for aesculetin, 0.94 ± 0.23 h for fraxetin, 0.83 ± 0.18 h for fraxin and 1.15 ± 0.15 h for polydatin. The results indicated that the absorption of Aesculin might be slow in beagle dog plasma. This method was successfully applied for pharmacokinetics in beagle dog plasma after oral administration of the extracts of Ledum palustre L. at a dosage of 0.27 g/kg.

  • Simultaneous Determination of Aesculin, Aesculetin, Fraxetin, Fraxin and Polydatin in Beagle Dog Plasma by UPLC-ESI-MS/MS and Its Application in a Pharmacokinetic Study after Oral Administration Extracts of Ledum palustre L.
    MDPI AG, 2018
    Co-Authors: Zhibin Wang, Wenbo Zhu, Hua Liu, Mengmeng Song, Bingyou Yang, Deqiang Yang, Qiuhong Wang, Haixue Kuang
    Abstract:

    A rapid, simple and sensitive ultra-performance liquid chromatography-electrospray-ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for the simultaneous determination of Aesculin, aesculetin, fraxetin, fraxin and polydatin in beagle dog plasma for the first time. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 mm × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.4 mL/min, using a mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). The analytes and IS were detected by multiple reaction monitoring (MRM) via negative ion mode with ion transitions of m/z 339.1–m/z 176.8 for Aesculin, m/z 176.8–m/z 88.9 for aesculetin, m/z 206.8–m/z 192.1 for fraxetin, m/z 369.1–m/z 206.9 for fraxin, m/z 389.1–m/z 227.0 for polydatin and m/z 415.2–m/z 295.1 for puerarin. This method was validated according to the FDA guidelines and the results met the requirements of analysis. The calibration curves of analytes were linear with correlation coefficients more than 0.9980. The intra- and inter-day precisions were less than 15% and the accuracy was within ±15%. The maximum plasma concentration (Cmax) of Aesculin, aesculetin, fraxetin, fraxin and polydatin was 46.75 ± 7.46, 209.9 ± 57.65, 369.7 ± 48.87, 67.04 ± 12.09 and 47.14 ± 12.04 ng/mL, respectively. The time to reach the maximum plasma concentration (Tmax) was 1.32 ± 0.38 h for Aesculin, 1.03 ± 0.27 h for aesculetin, 0.94 ± 0.23 h for fraxetin, 0.83 ± 0.18 h for fraxin and 1.15 ± 0.15 h for polydatin. The results indicated that the absorption of Aesculin might be slow in beagle dog plasma. This method was successfully applied for pharmacokinetics in beagle dog plasma after oral administration of the extracts of Ledum palustre L. at a dosage of 0.27 g/kg

  • simultaneous determination of anemoside b4 phellodendrine berberine palmatine obakunone esculin esculetin in rat plasma by uplc esi ms ms and its application to a comparative pharmacokinetic study in normal and ulcerative colitis rats
    Journal of Pharmaceutical and Biomedical Analysis, 2017
    Co-Authors: Lianrong Yang, Xin Meng, Haixue Kuang
    Abstract:

    A sensitive and rapid ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS/MS) method was developed for the simultaneous analysis of anemoside B4, phellodendrine, berberine, palmatine, obakunone, esculin, esculetin, toosendanin (IS1 of anemoside B4), tetrahydropalmatine (IS2 of phellodendrine, berberine, palmatine and obakunone) and scopoletin (IS3 of esculin and esculetin) and to compare the pharmacokinetics of these active ingredients in normal and ulcerative colitis rats. After methanol deproteinization, solvents were evaporated at 40°C under a gentle stream of nitrogen. Chromatography was performed using a C18 column with a gradient elution of 0.1% aqueous formic acid and acetonitrile at 0.4ml/min. Detection and measurement were performed on a 4000 QTRAP UPLC-MS/MS system from AB Sciex in the multiple reaction monitoring (MRM) mode. Phellodendrine, berberine, palmatine, obakunone, esculin, esculetin, tetrahydropalmatine (IS2) and scopoletin (IS3) were monitored under positive ionization conditions. Anemoside B4, and toosendanin (IS1) were monitored under negative ionization conditions. The optimized mass transition ion-pairs (m/z) were 1221.1/750.7 for anemoside B4, 343.2/193.2 for phellodendrine, 337.1/321.0 for berberine, 353.0/336.9 for palmatine, 455.1/161.1 for obakunone, 341.2/179.2 for esculin, 179.1/123.0 for esculetin, 573.4/531.4 for toosendanin (IS1), 356.2/192.2 for tetrahydropalmatine (IS2) and 193.0/133.1 for scopoletin (IS3).

Qiuhong Wang - One of the best experts on this subject based on the ideXlab platform.

  • simultaneous determination of Aesculin aesculetin fraxetin fraxin and polydatin in beagle dog plasma by uplc esi ms ms and its application in a pharmacokinetic study after oral administration extracts of ledum palustre l
    Molecules, 2018
    Co-Authors: Zhibin Wang, Haixue Kuang, Wenbo Zhu, Hua Liu, Mengmeng Song, Bingyou Yang, Deqiang Yang, Qiuhong Wang
    Abstract:

    A rapid, simple and sensitive ultra-performance liquid chromatography-electrospray-ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for the simultaneous determination of Aesculin, aesculetin, fraxetin, fraxin and polydatin in beagle dog plasma for the first time. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 mm × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.4 mL/min, using a mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). The analytes and IS were detected by multiple reaction monitoring (MRM) via negative ion mode with ion transitions of m/z 339.1⁻m/z 176.8 for Aesculin, m/z 176.8⁻m/z 88.9 for aesculetin, m/z 206.8⁻m/z 192.1 for fraxetin, m/z 369.1⁻m/z 206.9 for fraxin, m/z 389.1⁻m/z 227.0 for polydatin and m/z 415.2⁻m/z 295.1 for puerarin. This method was validated according to the FDA guidelines and the results met the requirements of analysis. The calibration curves of analytes were linear with correlation coefficients more than 0.9980. The intra- and inter-day precisions were less than 15% and the accuracy was within ±15%. The maximum plasma concentration (Cmax) of Aesculin, aesculetin, fraxetin, fraxin and polydatin was 46.75 ± 7.46, 209.9 ± 57.65, 369.7 ± 48.87, 67.04 ± 12.09 and 47.14 ± 12.04 ng/mL, respectively. The time to reach the maximum plasma concentration (Tmax) was 1.32 ± 0.38 h for Aesculin, 1.03 ± 0.27 h for aesculetin, 0.94 ± 0.23 h for fraxetin, 0.83 ± 0.18 h for fraxin and 1.15 ± 0.15 h for polydatin. The results indicated that the absorption of Aesculin might be slow in beagle dog plasma. This method was successfully applied for pharmacokinetics in beagle dog plasma after oral administration of the extracts of Ledum palustre L. at a dosage of 0.27 g/kg.

  • Simultaneous Determination of Aesculin, Aesculetin, Fraxetin, Fraxin and Polydatin in Beagle Dog Plasma by UPLC-ESI-MS/MS and Its Application in a Pharmacokinetic Study after Oral Administration Extracts of Ledum palustre L.
    MDPI AG, 2018
    Co-Authors: Zhibin Wang, Wenbo Zhu, Hua Liu, Mengmeng Song, Bingyou Yang, Deqiang Yang, Qiuhong Wang, Haixue Kuang
    Abstract:

    A rapid, simple and sensitive ultra-performance liquid chromatography-electrospray-ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for the simultaneous determination of Aesculin, aesculetin, fraxetin, fraxin and polydatin in beagle dog plasma for the first time. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 mm × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.4 mL/min, using a mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). The analytes and IS were detected by multiple reaction monitoring (MRM) via negative ion mode with ion transitions of m/z 339.1–m/z 176.8 for Aesculin, m/z 176.8–m/z 88.9 for aesculetin, m/z 206.8–m/z 192.1 for fraxetin, m/z 369.1–m/z 206.9 for fraxin, m/z 389.1–m/z 227.0 for polydatin and m/z 415.2–m/z 295.1 for puerarin. This method was validated according to the FDA guidelines and the results met the requirements of analysis. The calibration curves of analytes were linear with correlation coefficients more than 0.9980. The intra- and inter-day precisions were less than 15% and the accuracy was within ±15%. The maximum plasma concentration (Cmax) of Aesculin, aesculetin, fraxetin, fraxin and polydatin was 46.75 ± 7.46, 209.9 ± 57.65, 369.7 ± 48.87, 67.04 ± 12.09 and 47.14 ± 12.04 ng/mL, respectively. The time to reach the maximum plasma concentration (Tmax) was 1.32 ± 0.38 h for Aesculin, 1.03 ± 0.27 h for aesculetin, 0.94 ± 0.23 h for fraxetin, 0.83 ± 0.18 h for fraxin and 1.15 ± 0.15 h for polydatin. The results indicated that the absorption of Aesculin might be slow in beagle dog plasma. This method was successfully applied for pharmacokinetics in beagle dog plasma after oral administration of the extracts of Ledum palustre L. at a dosage of 0.27 g/kg

Noboru Harada - One of the best experts on this subject based on the ideXlab platform.

  • suppression of 8 oxo 2 deoxyguanosine formation and carcinogenesis induced by n nitrosobis 2 oxopropyl amine in hamsters by esculetin and esculin
    Free Radical Research, 2004
    Co-Authors: Takao Kaneko, Shoichi Tahara, Fumiyo Takabayashi, Noboru Harada
    Abstract:

    Effects of esculetin (6,7-dihydroxycoumarin) and its glycoside, esculin, on 8-oxo-2′-deoxyguanosine (8-oxodG) formation and carcinogenesis induced by a chemical carcinogen, N-nitrosobis(2-oxopropyl)amine (BOP), were examined in the pancreas of female Syrian golden hamsters. Animals were administered esculetin by gastric intubation into the stomach 30 min before BOP administration or ingestion of a diet containing esculin for 7 days before BOP administration, and killed 1 or 4 h after BOP treatment, and the contents of thiobarbituric acid-reacting substrates (TBARS) and 8-oxodG in the pancreas were determined. Both compounds suppressed significantly the BOP-induced increases in 8-oxodG and TBARS contents in hamster pancreas. We further investigated the effect of esculin on pancreatic carcinogenesis by the rapid production model induced by augmentation pressure with a choline-deficient diet, ethionine, methionine and BOP. Esculin was given ad libitum as a 0.05% aqueous solution in either the initiation or p...

  • inhibitory effect of esculin on oxidative dna damage and carcinogenesis induced by n nitrosobis 2 oxopropyl amine in hamster pancreas
    Biofactors, 2004
    Co-Authors: Takao Kaneko, Shoichi Tahara, Fumiyo Takabayashi, Noboru Harada
    Abstract:

    The effects of esculin, a natural coumarin compound, on the formation of 8-oxo-2'-deoxyguanosine (8-oxodG) and carcinogenesis induced by a chemical carcinogen, N-nitrosobis(2-oxopropyl)amine (BOP), were examined in the pancreas of female Syrian golden hamsters. Animals were given a diet containing esculin for 7 days, and killed 4~h after BOP treatment, and the contents of 8-oxodG were measured in the nuclear DNA of the pancreas. Esculin suppressed significantly the increase in the 8-oxodG content of hamster pancreas induced by BOP. Furthermore, the effect of esculin on the rapid production model experiment for pancreatic carcinogenesis using BOP was investigated. Esculin was given ad libitum as a 0.05% aqueous solution during either the initiation or promotion phases. The incidence of invasive tumors in animals given esculin during the initiation phase was significantly lower than in the control group, while the incidence in animals given esculin during the promotion phase showed no significant change. These results suggest that the intake of esculin has an inhibitory effect on BOP-induced oxidative DNA damage and carcinogenesis in hamster pancreas.

M Weiss - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of the aesculon cardiac output monitor by subxiphoidal doppler flow measurement in children with congenital heart defects
    European Journal of Anaesthesiology, 2009
    Co-Authors: Maren Tomaske, Oliver Kretschmar, Urs Bauersfeld, Katja Woitzek, Christian Balmer, Walter Knirsch, A Schmitz, M Weiss
    Abstract:

    BACKGROUND AND OBJECTIVE: To evaluate the noninvasive electrical velocimetry (Aesculon) monitor for cardiac output (CO) by subxiphoidal Doppler flow measurement in children. METHODS: CO was determined at the end of diagnostic or interventional cardiac catheterization for congenital heart defects. Standard ECG surface electrodes were attached in a vertical direction to the patients' left middle and lower neck, and lower thorax at the level of the heart and xiphoid process. Aesculon CO data were compared with a simultaneously measured CO by the subxiphoidal Doppler flow measurement technique. For each patient, measurements were repeated three times within 5 min. Whitney U-test, simple regression and Bland-Altman analysis were performed to compare CO values obtained by the two techniques. Data are given as range (median). RESULTS: A total of 36 children aged 5.7 (0.5-16.0) years were investigated. CO values obtained by Aesculon monitor [0.55-5.58 (2.62) l min] and subxiphoidal Doppler flow measurements [0.62-6.27 (3.05) l min] differed significantly between both methods (P = 0.04). Simple regression analysis revealed moderate correlation between CO values obtained from the two techniques (r = 0.5544, P < 0.001). Bias between the two methods was 0.31 l min with a precision of 1.92 l min. CONCLUSION: We conclude that electrical velocimetry using the Aesculon monitor does not reliably reflect absolute CO values as compared with subxiphoidal Doppler flow measurement.

  • cardiac output measurement in children comparison of aesculon cardiac output monitor and thermodilution
    BJA: British Journal of Anaesthesia, 2008
    Co-Authors: Maren Tomaske, Oliver Kretschmar, Urs Bauersfeld, Katja Woitzek, Christian Balmer, Walter Knirsch, A Schmitz, M Weiss
    Abstract:

    BACKGROUND: We compared cardiac output (CO) measurements by the non-invasive electrical velocimetry (Aesculon) monitor with the pulmonary artery catheter (PAC) thermodilution method in children. METHODS: CO values using the Aesculon monitor and PAC thermodilution were simultaneously recorded during cardiac catheterization in children. Measurements were performed under general anaesthesia. To compare, three consecutive measurements for each patient within 3 min were obtained. The means of the three values were compared using simple regression and Bland-Altman analysis. Data were presented as mean (sd). A mean percentage of <30% was defined to indicate clinical useful reliability of the Aesculon monitor. RESULTS: A total of 50 patients with a median (range) age of 7.5 (0.5-16.5) yr were enrolled in the study. Mean CO values were 3.7 (1.5) litre min(-1) (PAC thermodilution) and 3.1 (1.7) litre min(-1) (Aesculon) monitor). Analysis for CO measurement showed a good correlation between the two methods (r=0.894; P<0.0001). The bias between the two methods was 0.66 litre min(-1) with a precision of 1.49 litre min(-1). The mean percentage error for CO measurements was 48.9% for the Aesculon monitor when compared with PAC thermodilution. CONCLUSIONS: Electrical velocimetry using the Aesculon monitor did not provide reliable CO values when compared with PAC thermodilution. Whether the Aesculon monitor can be used as a CO trend monitor has to be assessed by further investigations in patients with changing haemodynamics.

Zhibin Wang - One of the best experts on this subject based on the ideXlab platform.

  • simultaneous determination of Aesculin aesculetin fraxetin fraxin and polydatin in beagle dog plasma by uplc esi ms ms and its application in a pharmacokinetic study after oral administration extracts of ledum palustre l
    Molecules, 2018
    Co-Authors: Zhibin Wang, Haixue Kuang, Wenbo Zhu, Hua Liu, Mengmeng Song, Bingyou Yang, Deqiang Yang, Qiuhong Wang
    Abstract:

    A rapid, simple and sensitive ultra-performance liquid chromatography-electrospray-ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for the simultaneous determination of Aesculin, aesculetin, fraxetin, fraxin and polydatin in beagle dog plasma for the first time. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 mm × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.4 mL/min, using a mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). The analytes and IS were detected by multiple reaction monitoring (MRM) via negative ion mode with ion transitions of m/z 339.1⁻m/z 176.8 for Aesculin, m/z 176.8⁻m/z 88.9 for aesculetin, m/z 206.8⁻m/z 192.1 for fraxetin, m/z 369.1⁻m/z 206.9 for fraxin, m/z 389.1⁻m/z 227.0 for polydatin and m/z 415.2⁻m/z 295.1 for puerarin. This method was validated according to the FDA guidelines and the results met the requirements of analysis. The calibration curves of analytes were linear with correlation coefficients more than 0.9980. The intra- and inter-day precisions were less than 15% and the accuracy was within ±15%. The maximum plasma concentration (Cmax) of Aesculin, aesculetin, fraxetin, fraxin and polydatin was 46.75 ± 7.46, 209.9 ± 57.65, 369.7 ± 48.87, 67.04 ± 12.09 and 47.14 ± 12.04 ng/mL, respectively. The time to reach the maximum plasma concentration (Tmax) was 1.32 ± 0.38 h for Aesculin, 1.03 ± 0.27 h for aesculetin, 0.94 ± 0.23 h for fraxetin, 0.83 ± 0.18 h for fraxin and 1.15 ± 0.15 h for polydatin. The results indicated that the absorption of Aesculin might be slow in beagle dog plasma. This method was successfully applied for pharmacokinetics in beagle dog plasma after oral administration of the extracts of Ledum palustre L. at a dosage of 0.27 g/kg.

  • Simultaneous Determination of Aesculin, Aesculetin, Fraxetin, Fraxin and Polydatin in Beagle Dog Plasma by UPLC-ESI-MS/MS and Its Application in a Pharmacokinetic Study after Oral Administration Extracts of Ledum palustre L.
    MDPI AG, 2018
    Co-Authors: Zhibin Wang, Wenbo Zhu, Hua Liu, Mengmeng Song, Bingyou Yang, Deqiang Yang, Qiuhong Wang, Haixue Kuang
    Abstract:

    A rapid, simple and sensitive ultra-performance liquid chromatography-electrospray-ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for the simultaneous determination of Aesculin, aesculetin, fraxetin, fraxin and polydatin in beagle dog plasma for the first time. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 mm × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.4 mL/min, using a mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). The analytes and IS were detected by multiple reaction monitoring (MRM) via negative ion mode with ion transitions of m/z 339.1–m/z 176.8 for Aesculin, m/z 176.8–m/z 88.9 for aesculetin, m/z 206.8–m/z 192.1 for fraxetin, m/z 369.1–m/z 206.9 for fraxin, m/z 389.1–m/z 227.0 for polydatin and m/z 415.2–m/z 295.1 for puerarin. This method was validated according to the FDA guidelines and the results met the requirements of analysis. The calibration curves of analytes were linear with correlation coefficients more than 0.9980. The intra- and inter-day precisions were less than 15% and the accuracy was within ±15%. The maximum plasma concentration (Cmax) of Aesculin, aesculetin, fraxetin, fraxin and polydatin was 46.75 ± 7.46, 209.9 ± 57.65, 369.7 ± 48.87, 67.04 ± 12.09 and 47.14 ± 12.04 ng/mL, respectively. The time to reach the maximum plasma concentration (Tmax) was 1.32 ± 0.38 h for Aesculin, 1.03 ± 0.27 h for aesculetin, 0.94 ± 0.23 h for fraxetin, 0.83 ± 0.18 h for fraxin and 1.15 ± 0.15 h for polydatin. The results indicated that the absorption of Aesculin might be slow in beagle dog plasma. This method was successfully applied for pharmacokinetics in beagle dog plasma after oral administration of the extracts of Ledum palustre L. at a dosage of 0.27 g/kg