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Masayasu Kurono - One of the best experts on this subject based on the ideXlab platform.

  • Metaboic Fate of Human Urinary Kallidinogenase (SK-827) (4): Inhibition of SK-827 by Human, Dog and Rat Plasma Inhibitors
    Drug Metabolism and Pharmacokinetics, 1994
    Co-Authors: Yukiharu Nakayama, Yoshiyuki Furuta, Tsuneaki Inoue, Masayasu Kurono
    Abstract:

    We investigated the inhibition of SK-827 by human, dog and rat plasma inhibitors using gel filtration column chromatography (Sephacryl S-300 Superfine). 1. In human plasma, there was one inhibitor which was revealed to be α1-antitrypsin (α1-AT) based on its enzymatic and immunological propaerties and the Elution Volume of the complex on gel filtration column chromatography. After 2 min incubation of 125I-SK-827 with human plasma at 37°C, 28% of 125I-SK-827 remained free, but was not detected 30 min later. 2. In dog plasma, there were two inhibitors which were described to be α1-AT and α2-macrogrobulin (α2-M) base on their enzymatic and immunological properties and the Elution Volume of the complex. The ratio of 125I-SK-827-α2-M complex and 125I-SK-827-α1-AT complex in the plasma was about 30 :70. After 5 min incubation of 125I-SK-827 with dog plasma at 37°C, 36% of 125I-SK-827 remained free, but was not detected 60 min later. 3. In rat plasma, there were two inhibitors which were revealed to be α1-AT and α2-M base on their enzymatic and immunological properties and the Elution Volume of the complex. The ratio of 125I-SK-827-α2-M complex and 125I-SK-827-α1-AT complex in the plasma was about 92 : 8. After 2 min incubation of 125I-SK-827 with rat plasma at 37°C, only 11% of 125I-SK-827 remained free.

Yukiharu Nakayama - One of the best experts on this subject based on the ideXlab platform.

  • Metaboic Fate of Human Urinary Kallidinogenase (SK-827) (4): Inhibition of SK-827 by Human, Dog and Rat Plasma Inhibitors
    Drug Metabolism and Pharmacokinetics, 1994
    Co-Authors: Yukiharu Nakayama, Yoshiyuki Furuta, Tsuneaki Inoue, Masayasu Kurono
    Abstract:

    We investigated the inhibition of SK-827 by human, dog and rat plasma inhibitors using gel filtration column chromatography (Sephacryl S-300 Superfine). 1. In human plasma, there was one inhibitor which was revealed to be α1-antitrypsin (α1-AT) based on its enzymatic and immunological propaerties and the Elution Volume of the complex on gel filtration column chromatography. After 2 min incubation of 125I-SK-827 with human plasma at 37°C, 28% of 125I-SK-827 remained free, but was not detected 30 min later. 2. In dog plasma, there were two inhibitors which were described to be α1-AT and α2-macrogrobulin (α2-M) base on their enzymatic and immunological properties and the Elution Volume of the complex. The ratio of 125I-SK-827-α2-M complex and 125I-SK-827-α1-AT complex in the plasma was about 30 :70. After 5 min incubation of 125I-SK-827 with dog plasma at 37°C, 36% of 125I-SK-827 remained free, but was not detected 60 min later. 3. In rat plasma, there were two inhibitors which were revealed to be α1-AT and α2-M base on their enzymatic and immunological properties and the Elution Volume of the complex. The ratio of 125I-SK-827-α2-M complex and 125I-SK-827-α1-AT complex in the plasma was about 92 : 8. After 2 min incubation of 125I-SK-827 with rat plasma at 37°C, only 11% of 125I-SK-827 remained free.

Shuichi Yamamoto - One of the best experts on this subject based on the ideXlab platform.

  • Theoretical background of short chromatographic layers. Optimization of gradient Elution in short columns.
    Journal of chromatography. A, 2005
    Co-Authors: Shuichi Yamamoto, Ayako Kita
    Abstract:

    Although linear salt gradient Elution ion-exchange chromatography (IEC) of proteins is commonly carried out with relatively short columns, it is still not clear how the column length affects the separation performance and the economics of the process. The separation performance can be adjusted by changing a combination of the column length, the gradient slope and the flow velocity. The same resolution can be obtained with a given column length with different combinations of the gradient slope and the flow velocity. This results in different separation time and Elution Volume at the same resolution. Based on our previous model, a method for determining the separation time and the Elution Volume relationship for the same resolution (iso-resolution curve) was developed. The effect of the column length and the mass transfer rate on the iso-resolution curve was examined. A long column and/or high mass transfer rate results in lesser Elution Volume. The resolution data with porous bead packed columns and monolithic columns were in good agreement with the calculated iso-resolution curves. Although the Elution Volume can be reduced with increasing column length, the pressure drop limits govern the optimum conditions.

  • Characterization of unstable ion-exchange chromatographic separation of proteins.
    Journal of chromatography. A, 1999
    Co-Authors: Shuichi Yamamoto, Peter Watler, Daphne Feng, Oliver Kaltenbrunner
    Abstract:

    Very fine separation of proteins by stepwise Elution ion-exchange chromatography is very often a unstable process. To characterize the unstability of such processes the Elution Volume variations were examined by the model equation which contained the ion-exchange capacity and the number of adsorption sites. The data needed for the model calculation were obtained from gradient Elution experiments. As a model separation system stepwise Elution of a model protein (β-lactoglobulin) near the isoelectric point on a weak cation-exchange chromatography column was chosen. The Elution Volume varied significantly with a small change in the ion-exchange capacity. It was found that the ionic strength of the Elution buffer must be adjusted in order to compensate a change in the Elution Volume due to the ion-exchange capacity variations. The ionic strength and the pH of the Elution buffer were also found to be important variables affecting the Elution Volume. In this model separation system, it was indicated that the pH should be within ±0.1 unit and the ionic strength within ±0.002 mol/l in order to meet the criteria (±5% Elution Volume variation). It is recommended that gradient Elution data be obtained for predicting Elution Volume variations in stepwise Elution. By using the gradient Elution data the process diagnosis can be performed, and the important information on the process stability can be obtained.

Anastasios Dondos - One of the best experts on this subject based on the ideXlab platform.

Tsuneaki Inoue - One of the best experts on this subject based on the ideXlab platform.

  • Metaboic Fate of Human Urinary Kallidinogenase (SK-827) (4): Inhibition of SK-827 by Human, Dog and Rat Plasma Inhibitors
    Drug Metabolism and Pharmacokinetics, 1994
    Co-Authors: Yukiharu Nakayama, Yoshiyuki Furuta, Tsuneaki Inoue, Masayasu Kurono
    Abstract:

    We investigated the inhibition of SK-827 by human, dog and rat plasma inhibitors using gel filtration column chromatography (Sephacryl S-300 Superfine). 1. In human plasma, there was one inhibitor which was revealed to be α1-antitrypsin (α1-AT) based on its enzymatic and immunological propaerties and the Elution Volume of the complex on gel filtration column chromatography. After 2 min incubation of 125I-SK-827 with human plasma at 37°C, 28% of 125I-SK-827 remained free, but was not detected 30 min later. 2. In dog plasma, there were two inhibitors which were described to be α1-AT and α2-macrogrobulin (α2-M) base on their enzymatic and immunological properties and the Elution Volume of the complex. The ratio of 125I-SK-827-α2-M complex and 125I-SK-827-α1-AT complex in the plasma was about 30 :70. After 5 min incubation of 125I-SK-827 with dog plasma at 37°C, 36% of 125I-SK-827 remained free, but was not detected 60 min later. 3. In rat plasma, there were two inhibitors which were revealed to be α1-AT and α2-M base on their enzymatic and immunological properties and the Elution Volume of the complex. The ratio of 125I-SK-827-α2-M complex and 125I-SK-827-α1-AT complex in the plasma was about 92 : 8. After 2 min incubation of 125I-SK-827 with rat plasma at 37°C, only 11% of 125I-SK-827 remained free.