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1.
We have established seven murine hybridoma cell lines which produce monoclonal antibodies (mAbs) against Pseudomonas aeruginosa elastase. The seven mAbs recognized at least six different epitopes on the elastase molecule. All mAbs inhibited both enzymatic activities of elastase and protease, in which elastin fluorescein and hide powder azure were used as substrates, respectively. One of them, mAb E-4D3, strongly neutralized enzymatic activities of peptidase in which furylacryloyl-glycyl-leucinamide was used as a substrate, as well as of elastase and protease. In contrast, the other six mAbs did not neutralize peptidase activity at all. The Ki value for furylacryloyl-glycl-leucinamide of E-4D3, as well as its Fab fragment, was comparable to those for metalloprotease inhibitors such as phosphoramidon and Zincov inhibitor. The binding of mAb E-4D3 was inhibited by phosphoramidon and Zincov inhibitor, but not by metal chelators such as EDTA and o-phenanthroline. A line of evidence suggests that mAb E-4D3 directly interacts with active site and highly neutralizes enzymatic activity of P. aeruginosa elastase. Data of Western blotting and ELISA suggest that mAb E-4D3 is likely to recognize an elastase molecule in a conformation-dependent manner as an epitope. In contrast, the neutralizing activity of the other mAbs against elastase and protease seems to be caused by a low accessibility of an enzyme to insoluble and high-molecular-mass substrates through the binding and steric hindrance of the mAbs to an enzyme. 相似文献
2.
Satoshi Shizukuishi Satoshi Nishii John Ellis Karl Folkers 《Biochemical and biophysical research communications》1980,95(3):1126-1130
The mean basal specific activities and the mean % deficiencies of the activity of the glutamic oxaloacetic transaminase of the erythrocytes were identical (n.s.) for a group of eight patients with a severe carpal tunnel syndrome and for a group of eight university students. There was no significant difference in the increases in the specific activities for the patients and the students at 4 concentrations of pyridoxal 5′-phosphate. The apparent Km for the patients and the students was 95 μM and 61 μM (n.s.) respectively. It is concluded from these data in conjunction with previous findings that the carpal tunnel syndrome is a deficiency disease of vitamin B6, which is probably primary rather than one of a dependency state. 相似文献
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4.
Two species of fiddler crab, Uca tetragonon(Herbst, 1790) and Uca vocans(Linnaeus, 1758), which belong to the subgenus Gelasimus, dwell on rocky shores and muddy–sandy tidal flats, respectively, in Phuket Is., Thailand. We investigated their feeding ecology in relation to the morphology of their feeding organs: minor food-handling chelipeds and maxillipeds. U. tetragononfed chiefly on rocks covered by filamentous green algae. U. vocansfed on the emerged sand and in shallow water along the shoreline and in pools. While feeding, both crabs made sand pellets beneath their mouthparts and discarded them, indicating that they divided the matter scooped up with their minor chelipeds into edible and inedible fractions by using the maxillipeds in the water passing through their buccal cavity. The morphology of maxillipeds hardly differed between the two species, which means that both species are flotation-feeders. The morphology of their minor chelipeds, however, differed: the tips of the dactyl and pollex were flat in U. tetragononand pointed in U. vocans.When the minor cheliped was closed, U. tetragononhad a hemispherical space in the distal one-fourth of the gape, which was closed by the framing keratin layers and a few setae of the dactyl and pollex. On the other hand, U. vocanshad an ellipsoidal space in the distal half of the gape. We consider these morphological characters to be adaptations to the different feeding substrates for retaining more food-laden sediment. We discuss the role of the setae on the minor chelipeds on the basis of the morphological differences between populations of U. tetragononin Phuket Is. and East Africa where the crab inhabits muddy–sandy tidal flats. 相似文献
5.
Eiji Niwa En-Sheng Chen Satoshi Kanoh Teruo Nakayama 《Bioscience, biotechnology, and biochemistry》2013,77(11):3067-3071
The linearity of the stress-strain relationship for food gel is limited to a very narrow range of the strain (usually less than 0.1 as a Cauchy measure). The reason is thought due to the change in cross-sectional area of the gel upon deformation. In this report, the cross-sectional area was approximately corrected of the compressed gel on the assumption that the gel expanded uniformly without changing its volume upon compression. In cases when the initial Young’s modulus was calculated from the thus-corrected area for some food gels, the linearity was increased for a wider range of strain. 相似文献
6.
Human and nonhuman primates comprehend the actions of other individuals by detecting social cues, including others’ goal-directed motor actions and faces. However, little is known about how this information is integrated with action understanding. Here, we present the ontogenetic and evolutionary foundations of this capacity by comparing face-scanning patterns of chimpanzees and humans as they viewed goal-directed human actions within contexts that differ in whether or not the predicted goal is achieved. Human adults and children attend to the actor’s face during action sequences, and this tendency is particularly pronounced in adults when observing that the predicted goal is not achieved. Chimpanzees rarely attend to the actor’s face during the goal-directed action, regardless of whether the predicted action goal is achieved or not. These results suggest that in humans, but not chimpanzees, attention to actor’s faces conveying referential information toward the target object indicates the process of observers making inferences about the intentionality of an action. Furthermore, this remarkable predisposition to observe others’ actions by integrating the prediction of action goals and the actor’s intention is developmentally acquired. 相似文献
7.
8.
Atsunori Kashiwagi Kazuyuki Sasaki Tamio Noguchi Takehiko Tanaka 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,582(2):221-233
A factor responsible for stimulating an increase in ornithine decarboxylase activity in the liver of mice was found in tumor cell-free ascites fluid of mice 3 days after inoculation of tumor cells. The factor was purified about 70-fold in 25% yield from tumor cell-free ascites fluid. As little as 1 μg of protein of purified fraction, injected intraperitoneally into normal mice, significantly increased the activity of ornithine decarboxylase in the liver. The most active preparation of the factor formed two major protein bands on analytical polyacrylamide gel electrophoresis and both these bands stained with periodic acid-Schiff's reagent. The factor was a heat-labile, alkaline-stable, acidic protein with a molecular weight of more than 300 000. It was inactivated by treatment with 10 mM dithiothreitol, 5M urea, pronase or mixed glycosidase, but was stable on treatment with DNAase, RNAase or neuraminidase. 相似文献
9.
Identification and partial purification of a novel tumor-derived protein that induces tissue factor on cultured human endothelial cells 总被引:2,自引:0,他引:2
Conditioned medium of a human bladder carcinoma cell line (J82) was found to induce tissue factor synthesis in cultured human umbilical vein endothelial cells (HUVEC). A protein present in the J82 conditioned medium was partially purified by FPLC using a combination of MONO Q and Superose 6 columns. The bladder carcinoma-derived cytokine (BCDC) exhibited a Mr of 22 kDa by gel permeation HPLC. Polyclonal antibody against either interleukin-1, tumor necrosis factor, or transforming growth factor-beta failed to inhibit the ability of the conditioned medium to induce HUVEC tissue factor activity, suggesting that this tumor cell line secretes a novel cytokine responsible for HUVEC tissue factor induction. 相似文献
10.
Yoshiaki Fukuda Kohzoh Imai Kenju Miura Masashi Matsui Toshihiro Nakanishi Hiroshi Nakazato Johji Masukawa Toshiyuki Higashide Yuji Hinoda Teruhisa Noguchi Akira Yachi 《Cancer immunology, immunotherapy : CII》1988,27(1):26-32
Summary There have been few reports stating that monoclonal antibody alone inhibits human solid tumor growth in vivo. The present study demonstrated that monoclonal antibody S1 (IgG2a), which recognized the antigenic determinant of the carbohydrate moiety, showed antibody-dependent cell (or macrophage)-mediated cytotoxicity (ADCC or ADMC) in conjunction with murine splenocytes of both BALB/c and athymic mice. In vivo experiments demonstrated that the antibody S1 clearly prolonged the survival of athymic mice which had been inoculated with a human liver carcinoma cell line. In addition, the antibody S1 significantly suppressed the human hepatoma line transplanted s.c. into nude mice. 125I-Labeled monoclonal antibody S1 revealed that the antibody accumulated significantly in the tumor mass. Many mononuclear cells were observed surrounding tumor cells when the antibody was given. This model system might be useful for analyzing the ADCC (or ADMC) mechanism in vivo. 相似文献