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31.
T Yoshimura T Miyoshi M Imaki T Tamura M Fujii K Matsumoto T Toumiya Y Hori T Nakamura M Tanada 《Acta biologica Hungarica》1986,37(3-4):235-241
Changes in the activity of serum gamma-glutamyl transpeptidase (gamma-GTP) and the percentage of the gamma-GTP fraction in healthy young men given a high carbohydrate diet (480-636 g/day, 80% of the total energy) for 21 days were examined. Serum total gamma-GTP activity showed no significant change in four healthy young volunteers who received high carbohydrate diet for 21 days. However, the percentage of the gamma-GTP (1) fraction increased significantly (P less than 0.01) from the basal level of 55.6 +/- 4.0% to 67.6 +/- 0.9% on day 10, and then decreased to 58.4 +/- 1.4% on day 21. When the experimental diet was replaced by usual diet, the percentage of the gamma-GTP (1) fraction returned to the same level as before the experiment. It is concluded from the results that the nutrient intake affects the percentage of gamma-GTP (1), but not the total serum gamma-GTP activity. 相似文献
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Summary Zymogramic analysis of esterase in the mouse, rat and guinea-pig salivary glands was undertaken and demonstrated species and organ specificities of esterase with electrophoretic method. Salivary glands esterase was classified into A, B and C types based on the electrophoretic mobility. Mouse submandibular gland had the most complicated pattern, while guinea-pig showed the simpliest patterns which was devoid of B type of esterase. Rat salivary glands exhibited rather regular patterns. Similar zymogram patterns were obtained with many kinds of ester compounds, that is simple and substituted naphthol esters and indoxyl derivatives. The tests of inhibition and activation for esterase activity was obtained. Histochemical properties applied to inhibitor test in the esterase zymogram patterns showed no marked differences between ducts and acini. 相似文献
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Identification of high affinity receptors for human monocyte chemoattractant protein-1 on human monocytes 总被引:17,自引:0,他引:17
The binding of human monocyte chemoattractant protein-1 (MCP-1) to human monocytes was studied. MCP-1 was radioiodinated with Iodo-beads (Pierce Chemical Co., Rockford, IL) without significant loss of biologic activity. 125I-MCP-1 binding to PBMC occurred within 5 min at 0 degrees C and the binding was inhibited by unlabeled MCP-1 dose dependently but not by neutrophil attractant/activation protein-1 or FMLP. 125I-MCP-1 bound to monocytes; no significant binding to either neutrophils or lymphocytes was observed. Scatchard plot analysis indicated that monocytes had a minimum of 1700 +/- 600 binding sites per cell with a Kd of 1.9 +/- 0.2 x 10(-9) M. For analysis of binding by flow cytometry, MCP-1 was biotinylated. In contrast to radioiodination, biotinylation resulted in loss of activity; potency was 10-fold less, but the efficacy was retained. Detection by flow cytometry of bound biotinylated MCP-1 with avidin-FITC confirmed results obtained with 125I-MCP-1. Biotinylated MCP-1 bound to monocytes but not to lymphocytes; and the binding was inhibited by a 100-fold excess of unlabeled MCP-1. 相似文献
40.
Leukocyte specificity and binding of human neutrophil attractant/activation protein-1 总被引:13,自引:0,他引:13
E J Leonard A Skeel T Yoshimura K Noer S Kutvirt D Van Epps 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(4):1323-1330
Neutrophil attractant/activation protein-1 (NAP-1) was previously shown to attract human neutrophils, but not monocytes. The purpose of this study was to determine if NAP-1 interacted with other types of blood leukocytes. In addition to its chemotactic activity for neutrophils, NAP-1 induced chemotactic responses by T lymphocytes and basophils. Chemotactic potency (10(-8) M for an optimal response) was the same for all three cell types. However, NAP-1 caused a chemotactic response in excess of random migration of 7% or 16% of basophils (depending on the medium used) and only 9% of T lymphocytes, in contrast to 30% of neutrophils. This agonist was not chemotactic for partially purified normal human eosinophils. The symmetrical histogram obtained by flow cytometry of neutrophils equilibrated at 0 degree C with fluoresceinated NAP-1 indicates that all neutrophils bound the ligand. A dose-response curve plateau, and inhibition of binding of NAP-1-FITC by unlabeled ligand are evidence for saturable binding to receptors, estimated to be 7000 per cell. Our results suggest that, for induction of an acute inflammatory response, the quantitatively significant action of NAP-1 is on neutrophils. 相似文献