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81.
Kenji Kawakami Kamruddin Ahmed Yoshiaki Utsunomiya Naoto Rikitomi Akihiro Hori Kazunori Oishi Tsuyoshi Nagatake 《Microbiology and immunology》1998,42(10):697-702
Nontypable Haemophilus influenzae (NTHI) is one of the major pathogens of human respiratory infections and has the ability to attach to pharyngeal epithelial cells. We characterized the epithelial cell receptor to which NTHI bind. Neuraminidase pretreatment of pharyngeal epithelial cells resulted in a significant decrease in NTHI attachment, suggesting sialic acid as an important component of the receptor. The attachment was not decreased in NTHI pretreated with 1,000 μg/ml of fucose, N-acetyl-neuraminic acid, N-acetyl-glucosamine, N-acetyl-galactosamine, acetyl-salicylic acid and colominic acid. Only treatment with gangliosides D1a, D1b and D2 at a concentration of 12.5 μg/ml significantly decreased the attachment. On the other hand, treatment with gangliosides M1, M2, M3, D3, T1b and asialoganglioside M1 did not decrease the attachment of NTHI. Only ganglioside D2 inhibited the attachment significantly at a concentration of 12.5 ng/ml. Other isolates of NTHI showed a decrease in attachment after treatment with ganglioside D2. Treatment of cells with anti-human GD2 monoclonal antibody also decreased the attachment of NTHI in a dose-dependent manner. This study indicates that sialic acid glycoconjugate, GD2, is one of the receptors of NTHI on human pharyngeal epithelial cells. 相似文献
82.
NRSF regulates the fetal cardiac gene program and maintains normal cardiac structure and function 总被引:1,自引:0,他引:1
83.
To prepare an immobilized protease with a high activity for transesterification of vinyl n-butyrate with 3-methyl-1-butanol (isoamyl alcohol) in organic media, a protease was entrapped into organic–inorganic hybrid silica gel on Celite 545 by the sol-gel method. When propyltrimethoxysilane was used as the organic silane precursor mixed with tetramethoxysilane at a molar ratio of 16:1, the hybrid gel-entrapped protease on Celite 545 had 8 times the activity of the protease deposited on Celite 545 from 35 to 85°C. 相似文献
84.
Hypotransferrinemic (HP) mice have a splicing defect inthe transferrin gene, resulting in <1% of the normal plasma levels of transferrin. They have severe anemia, suggesting that transferrin is essential for iron uptake by erythroid cells in the bone barrow. To clarify the significance of transferrin on iron delivery to the bone marrow, iron concentration and 59Fe distribution were determined in 7-day-old HP mice. Iron concentration in the femur, bone containing the bone marrow, of HP mice was approximately twice higher than in wild type mice. Twenty-four h after injection of 59FeCl3, 59Fe concentration in the bone and bone marrow of HP mice was also twice higher than in wild type mice. The present findings indicate that iron is abnormally delivered to the bone marrow of HP mice. However, the iron seems to be unavailable for the production of hemoglobin. These results suggest that transferrin-dependent iron uptake by erythroid cells in the bone marrow is essential for the development of erythrocytes. 相似文献
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88.
Tokuma Yanai Haruaki Taniguchi Hiroki Sakai Kazunori Yoshida Naoto Kimura Akira Katou Yuji Oishi Toshiaki Masegi 《Journal of medical primatology》1996,25(4):309-312
Abstract: A rare case of bilateral adrenal myelolipomas in a female cotton-top tamarin is reported. Large bilateral masses in the adrenal glands were composed of mature adipose cells containing varying amounts of hematopoietic cells of the myeloid, erythroid, and megakaryocyte series. The gross and histologic features of this case closely resemble human “giant” adrenal myelolipomas. 相似文献
89.
Pre-term birth is the leading cause of perinatal and neonatal mortality, 40% of which are attributed to the pre-term premature rupture of amnion. Rupture of amnion is thought to be associated with a corresponding decrease in the extracellular collagen content and/or increase in collagenase activity. However, there is very little information concerning the detailed organisation of fibrillar collagen in amnion and how this might influence rupture. Here we identify a loss of lattice like arrangement in collagen organisation from areas near to the rupture site, and present a 9% increase in fibril spacing and a 50% decrease in fibrillar organisation using quantitative measurements gained by transmission electron microscopy and the novel application of synchrotron X-ray diffraction. These data provide an accurate insight into the biomechanical process of amnion rupture and highlight X-ray diffraction as a new and powerful tool in our understanding of this process. 相似文献
90.
The unicellular green alga Chlorella sorokiniana ANA9 is highly resistant to heavy metals, and its metal-binding proteins are induced in the presence of cadmium. A novel
cadmium-binding protein in C. sorokiniana cultured in 100 mg/l cadmium ions for 4 days was isolated and characterized. The crude protein extract was obtained by cell
disruption and partly purified by ammonium sulfate precipitation. After purification by anion-exchange chromatography with
diethylaminoethyl (DEAE)-Sepharose CL-6B, the protein was further purified by gel filtration with Sephacryl S-100, followed
by Sephadex G-75. The molecular weight of the purified protein was determined to be 11.5 kDa by sodium dodecyl sulfate–polyacrylamide
gel electrophoresis. The cadmium binding capacity of the purified protein was 119 μg/mg. The involvement of thiol coordination
in metal-ion binding was confirmed by measuring the ultraviolet spectrum. This article is the first to describe the metallothionein-like
cadmium-binding protein from Chlorella species, the expression of which is induced by cadmium exposure. 相似文献