Akira Koshiro

Analysis of K. pneumoniae by Monoclonal Antibody: Immunohistochemical Detection of K. pneumoniae Surface Antigen Injected into Mice and Rats

The monoclonal antibody Kp62 recognized surface antigenic determinants of some strains of Klebsiella pneumoniae. The antigen recognized by Kp62 was demonstrated on the bacterial surface using immunoelectron microscopy. Kp62 reacted with K. pneumoniae No. 1 or K. pneumoniae B 5055 and lipopolysaccharide (LPS) from the same bacteria. However, Kp62 was not inhibited by the LPS from Escherichia coli (E. coli) O111:B4 and E. coli O55:B5. Thus, Kp62 might be a useful monoclonal antibody to detect K. pneumoniae and LPS from K. pneumoniae. The possibility to visualize the localization of K. pneumoniae LPS injected into animals using immunohistochemical methods with this monoclonal antibody was examined. It was possible to detect the injected LPS in the spleen of mouse and rat with the monoclonal antibody to K. pneumoniae. In order to detect the early events taking place in the spleen after intravenous injection of LPS, time course of LPS distribution in mice and rats was studied. After 30 min, 2, 4, 8 and 24 h LPS localized in the marginal zone (MZ) in mice and rats, although the degree of LPS positive cells varied. The cells responsible for trapping the injected LPS appeared to be marginal zone macrophages. The early trapping of LPS by marginal zone macrophages was thought to be important for the following immune responses to the injected LPS. Interestingly the antigenic determinant on the injected LPS appeared to last long on or within the cells in the spleen from the injected animals. Such a remaining antigen might be important for the continuous stimulation of B cells by the LPS. With respect to the distribution of red pulp (RP) and white pulp (WP), we found the varied distribution of LPS between mouse and rat, and SPF and conventionally fed (Conv) animals. For example, LPS-positive cells in RP of rat were scarce, while significant degree of LPS-positive cells were observed in mice. And in WP, LPS-positive cells were observed in Conv DA rats, but not in mice or SPF-fed Wistar rats. These results may suggest that the mode of antigen processing may be different in the spleen of rat and mouse or even among the different strain of rats and previous sensitization to the LPS (or the similar antigenic determinants) may lead to the different distribution of LPS in the spleen. The monoclonal antibody specifically raised against K. pneumoniae was shown to be very useful to follow the fate of LPS derived from K. pneumoniae using immunohistochemical method.(ABSTRACT TRUNCATED AT 400 WORDS)

Production of monoclonal antibodies against surface antigenic determinants of Klebsiella pneumoniae

The production of four murine monoclonal antibodies (Kp26, Kp53, Kp62 and Kp71) to Klebsiella pneumoniae surface antigen(s) is described. The binding of all four monoclonal antibodies to K. pneumoniae was inhibited by F(ab′)2 fragments of normal human serum IgG, suggesting that the antigenic determinants of K. pneumoniae detected by the four monoclonal antibodies may be similar to those recognized by human serum IgG. The antigen identified by Kp62 was purified from a deoxycholate‐solubilized bacterial fraction using immunoaffinity chromatography. The molecular weight of the antigen was determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis to be 50 000–70 000.

Immunohistochemical study of epoxide hydrolase induced by trichloroethylene in rat liver

Epoxide hydrolase catalyzes the hydrolation of potentially toxic, electrophilic epoxides that are often generated during cytochrome P-450 catalyzed monooxigenation, forming the corresponding transdihydrodiols. It is well-known that trichloroethylene is metabolized by cytochrome P-450 containing mixed-function oxidase systems to trichloroethylene oxide, which decomposes to other metabolites. As trichloroethylene is an epoxide, epoxide hydrolase is suspected to catalyze the hydrolation of trichloroethylene oxide. No reports have appeared about the relationship between trichloroethylene and epoxide hydrolase. In this report, the authors studied the effect of trichloroethylene on epoxide hydrolase immunohistochemically.

Prediction of the Stability of Meclofenoxate Injection in Parenteral Admixtures

A new method for predicting pharmaceutical stability in parenteral admixtures was studied using meclofenoxate hydrochloride injection as a model preparation. The pH and temperature of clinical parenteral admixtures are not constant, unlike experimental buffer solutions, and it is impossible to predict the accurate degradation ratio by the preceding method described by many authors. This study provides a solution to this problem, making possible the accurate prediction of degradation ratios of pharmaceuticals even in such complicated systems.

Disproportionation in hydrolysis of pyrimido[4,5-b]quinoline-2(3H),4(10H)-diones (5-deazaflavins)

Treatment of 5-deazaflavins with concentrated aqueous potassium hydroxide led to the exclusive formation of 1,5-dihydro-5-deazaflavins and 1,5-dihydro-5-deazaflavin-5-ones via intermolecular oxidation–reduction between initially formed 5-hydroxy-1,5-dihydro-5-deazaflavins and unchanged 5-deazaflavins; under dilute alkaline conditions the reverse oxidation–reduction between 1,5-dihydro-5-deazaflavins and 1,5-dihydro-5-deazaflavin-5-ones occurred to form the original 5-deazaflavins and 5-hydroxy-1,5-dihydro-5-deazaflavins, which were oxidized to 1,5-dihydro-5-deazaflavin-5-ones by air. When hydrolysis was carried out with dilute alkaline solution, the corresponding 2-oxoquinoline-3-carboxylic acids were obtained besides the disproportionation products 1,5-dihydro-5-deazaflavins and 1,5-dihydro-5-deazaflavin-5-ones. This disproportionation and hydrolytic scission at the 2-position compete with each other. Higher concentrations of hydroxide ion favoured the formation of the reduced 5-deazaflavins and 5-ketones by disproportionation and reduced the proportion of 2-quinolones formed by hydrolytic scission.

Quality Comparison of Pentoxifylline Tablets

Quality tests such as weight, hardness, disintegration, content, content uniformity and dissolution were made on 6 brands of pentoxifylline enteric-coated tablets, consisting of 1 original product and 5 me-too products.There were significant differences in the results of the tests among these products which were, however, confirmed to have fairly good qualities except in the dissolution properties of 2 me-too products. On the 2 products, the dissolution of pentoxifylline in the 1st fluid (pH 1.2) in JP X Disintegration Test was studied under a mild condition using rotating basket apparatus. Thus, both products were found to be unqualified. In this study, the original product was proved to have satisfactory qualitiy.