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Biomedical subjects

K Kojima

Publications and source records attributed to K Kojima.

At least 577 records · Page 32Linked to original sources
PubMed1987

Diplococcal beta-galactosidase with a specificity reacting to beta 1-4 linkage but not to beta 1-3 linkage as a useful exoglycosidase for the structural elucidation of glycolipids.

Diplococcal beta-galactosidase, which is known to be useful for the structural studies of glycoprotein-linked oligosaccharides, was found to show the same substrate specificity in cleaving Gal beta 1-4 linkages of glycolipids as that of the oligosaccharides. The optimum conditions of beta-galactosidase in the 80% ammonium sulfate precipitates of the culture medium of Streptococcus (Diplococcus) pneumoniae were determined with nLcOse4Cer radiolabeled by the galactose oxidase-NaB3H4 procedure. Detergent was required for the highest activity, and different combinations of several buffers and detergents showed different properties in stimulating beta-galactosidase, and in enhancing or suppressing N-acetyl-beta-hexosaminidase which was contaminated in the enzyme preparation. The optimum pH was found to be at 6.5, and specific activity and Km were 8.1 nmol/mg protein/h and 1 nmol, respectively. While more than 70% of beta-galactose was liberated from LacCer and nLcOse4Cer within 1 h under the optimum conditions to form GlcCer and nLcOse3Cer, respectively, none was liberated from LcOse4Cer, GalCer, GgOse4Cer, GbOse3Cer, IV3 alpha GalnLcOse4Cer, and Il3NeuAcGgOse4Cer, showing the substrate specificity solely to Gal beta 1-4 linkage.

Carbohydrate Conformation↗
PubMed1987

Serum activities of dipeptidyl-aminopeptidase II and dipeptidyl-aminopeptidase IV in tumor-bearing animals and in cancer patients.

Serum activities of dipeptidyl-aminopeptidases (DAP) II and IV were measured in tumor-bearing animals and in patients with blood and solid cancers using highly sensitive and specific fluorometric methods. In mice with intraperitoneal or subcutaneous implantation of Ehrlich ascites tumor cells, serum DAP II activity was increased and serum DAP IV activity was decreased, resulting in a significant increase in the ratio of serum DAP II and DAP IV activities. The increase in the ratio of these two activities paralleled the size of the subcutaneous tumors. However, both serum DAP II and DAP IV activities were increased in rats with experimental hepatic cancer induced by 3'-methyl-4-dimethylaminoazobenzene, and the increase in the ratio of the two activities was not significant. In cancer patients, as compared with healthy subjects, serum DAP II activity was increased and serum DAP IV activity was decreased, the ratio of serum DAP II and DAP IV activities being markedly increased in cancer patients. Both serum DAP II and DAP IV activities were increased in patients with hepatic cancer as were those in rats with hepatic cancer, but the increase in DAP II was greater than that of DAP IV; thus the ratio of the two activities increased significantly. These data suggest that the increase of the serum DAP II/DAP IV ratio could be a biochemical index of cancer.

Adult↗
PubMed1987

[Evaluation of pN factors in patients with primary lung cancer by using perfusion, inhalation and ventilation studies].

The interpretation of scintigraphic patterns and the role of pathophysiological mechanisms in patients with primary lung cancer were investigated. To determine the relative roles of perfusion, inhalation and ventilation scintigraphy, the relationship between the count ratio of the affected side to the healthy side and the post-surgical histological lymph nodes factors were observed in this study. These scintigraphic count ratio's in patients with primary lung cancer did not reflect the pN factors except in the perfusion study in patients with hilar primary lung cancer.

Humans↗
PubMed1987

Semisynthetic beta-lactam antibiotics. III. Effect on antibacterial activity and comt-susceptibility of chlorine-introduction into the catechol nucleus of 6-[(R)-2-[3-(3,4-dihydroxybenzoyl)-3-(3-hydroxypropyl)-1-ureido]-2- phenylacetamido]penicillanic acid.

The resistance of 6-[(R)-2-[3-(3,4-dihydroxybenzoyl)-3-(3-hydroxypropyl)-1-ureido]-2- phenylacetamido]penicillanic acid (1a) to metabolism by catechol-O-methyl-transferase (COMT) was increased by introduction of the chlorine atom into the catechol moiety. Penicillins (1b-1d) having one or two chlorine atoms at the positions adjacent to the hydroxyl group were found to have greater stability to COMT. This resulted in greater efficiency in vivo in experimental Pseudomonas aeruginosa and Escherichia coli infections. In vitro activities were essentially unchanged.

Animals↗