Protein error of pH indicators in the presence of detergents.

The characteristics of color development due to a protein error in the dye-binding method in the presence of a non-ionic detergent has been investigated by the calculations based on the chemical equilibrium of a protein error. The calculation results were compared with those obtained using three pH indicators (Bromophenol Blue, Bromocresol Green and Bromocresol Purple) and three non-ionic detergents in the pH region from 1 to 13. In the experiments, the color development increased with the lower concentrations of the detergents, but decreased at higher concentrations.

Analysis of the difference in color development in the dye-binding method due to the kind of buffer solution.

In a dye-binding method using a pH indicator, color development has reportedly been affected by the kind of buffer solution used in the color reagent. This phenomenon was analyzed by using a calculation based on the assumption that the anion of the buffer solution also reacts with protein. Color development decreases with increases in the anion concentration of the buffer solution and in the equilibrium constant of the reaction between the anion and protein.

Characteristics of a protein error in determination of serum protein in the presence of inorganic salt.

There is a possibility that the color development of the dye-binding method based on a protein error of a pH indicator is affected by the coexisting inorganic salt. Thus, the author theoretically and experimentally investigated the effect of the inorganic salt on the protein error. In a theoretical analysis, the anion of an inorganic salt, like the dissociated dye and buffer anions, was assumed to react with the protein, forming a colorless anion-protein complex.

Theoretical analysis concerning the characteristics of a dye-binding method for determining serum protein based on protein error of pH indicator: effect of buffer concentration of the color reagent on the color development.

In the dye-binding method based on protein error of a pH indicator, the color development has been reported to be markedly affected by the buffer concentration of the color reagent. In this study, the author analyzed this phenomenon by a theoretical calculation based on the chemical equilibrium of protein error. The calculation was performed on the assumption that both the dissociated dye anion and the anion contained in the buffer solution react with protein, forming a dye-protein complex and an anion-protein complex, respectively.

Reinvestigation of clinical value of Rivalta reaction of puncture fluid.

Rivalta reaction is still used as a puncture fluid test for differentiation of exudate and transudate. However, the test method of Rivalta reaction has not been standardized, or positive precipitates for the reaction have not been investigated. Thus, we clarified the measurement method, and investigated Rivalta reaction-positive proteins.

The upper limit pH in the dye-binding method for the determination of serum protein via measurements of the absorbance increase produced by protein error.

In the dye-binding method for determining the albumin concentration, the absorbance increase due to the change of the color shade by protein error of a pH indicator can be measured by a spectrophotometer. This absorbance increase is observed only in a restricted pH region, but this pH region is not theoretically studied yet. Thus, the author investigated the upper limit pH (pHUL) at which the absorbance increase occurs by the theoretical calculation, and compared these results with those obtained experimentally using four pH indicators.

The effect of different buffers and amounts of intestinal alkaline phosphatase isoforms on total alkaline phosphatase activity.

Background: The transphosphorylating accepter buffers (2-amino-2-methyl-1-propanol, AMP; N-methyl-D-glucamine, MEG; diethanolamine, DEA and 2-ethylaminoethanol, EAE) have been widely used for the measurement of serum total alkaline phosphatase activity (ALP) in clinical laboratories, and the individual isozyme are activated differently by respective buffers.

Materials And Methods: We examined the activity of serum ALP using four buffers with levels of both high molecular weight intestinal alkaline phosphatase (HIAP) and normal molecular weight intestinal alkaline phosphatase (NIAP). We classified 80 healthy subjects into two groups of blood group B or O secretors (n=36) and other blood groups (n=44).

Guidance for selecting the measurement conditions in the dye-binding method for determining serum protein: theoretical analysis based on the chemical equilibrium of protein error.

A methodology for selecting the measurement conditions in the dye-binding method for determining serum protein has been studied by a theoretical calculation. This calculation was based on the fact that a protein error occurs because of a reaction between the side chains of a positively charged amino acid residue in a protein molecule and a dissociated dye anion. The calculated characteristics of this method are summarized as follows: (1) Although the reaction between the dye and the protein occurs up to about pH 12, a change in the color shade, called protein error, is observed only in a pH region restricted within narrow limits.

Isolation and characterization of a human alternative complement pathway-inhibiting protein from larval hemolymph of the silkworm, Bombyx mori.

An alternative complement pathway-inhibiting protein (ACPIP), which inhibits the activation of the alternative complement pathway (ACP) of the human serum, was isolated from larval hemolymph of the silkworm, Bombyx mori, by using ammonium sulfate fractionation and column chromatographies to homogeneity. About 400microg of ACPIP was routinely obtained from 20ml hemolymph. The purified ACPIP preparation consisted of two distinct polypeptides (34 and 32kDa) on SDS-PAGE.

Specific gel electrophoresis method detects two isoforms of human intestinal alkaline phosphatase.

We have demonstrated that the 6.0% polyacrylamide disc gel electrophoresis (PAGE) method in the presence of 1% Triton X-100 clearly separated both normal molecular mass intestinal alkaline phosphatase (NIAP) and bone alkaline phosphatase (BAP) in serum regardless of the ABO blood group and the secretor status of the subjects. From the results under the usual 7.