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31.
Unique tissue distribution of a mouse macrophage C-type lectin 总被引:7,自引:2,他引:5
Mizuochi Shigeki; Akimoto Yoshihiro; Imai Yasuyuki; Hirano Hiroshi; Irimura Tatsuro 《Glycobiology》1997,7(1):137-146
We examined mouse tissue for the expression of macrophage galactose/N-acetylgalactosamine-specificC-type lectin using a rat monoclonal antibody (mAb) specificfor this lectin (mAb LOM-14). The binding of mAb LOM-14 wasdetected in detergent extracts from tissue by means of immunoblottinganalysis. It was shown that this mAb did not cross-react withmouse hepatic lectins, a structural homologue. The macrophagelectin was widely distributed among various mouse tissues asjudged by the affinity isolation followed by the immunochemicaldetection. The exceptions were brain, liver, kidney, small intestine,and peripheral blood. Extracts from these organs exhibited,at best, very weak signals upon mAb LOM-14 binding, despitethe presence of cells expressing macrophage markers. The mostintense signal was observed in the extract from skin, suggestingthat cells expressing this lectin are abundant in skin. Thetissues shown to contain this lectin were further investigatedby immunohistochemical staining of the sections. Cells weredistributed in the connective tissue and in the interstice,particularly the dermis and subcutaneous layer of skin. Cellslocalized in the epithelium of skin (epidermis) or other epitheliathat we examined were not stained. Perivascular localizationof cells stained with mAb LOM-14 was also demonstrated in cardiacand skeletal muscle tissues. Immunoelectron microscopy revealedthe presence of this lectin along the rough endoplasmic reticulum.In conclusion, the distribution of C-type lectin specific forgalactose/N-acetylgalactosamine in mice was unique. The connectivetissue-specific distribution should provide important informationon the biological role of this lectin. lectin macrophage calcium-type lectin connective tissue 相似文献
32.
Shinya Nomoto Michiaki Takasaki Hiroshi Naraoka Kaoru Harada 《Origins of life and evolution of the biosphere》1984,14(1-4):123-130
Flames of flammable gases, when blown against a surface of an aqueous solution of organic compounds, were found to induce oxidation as well as other reactions in the solution. This reaction would be regarded as a new model for formation of bioorganic molecules in the primitive hydrosphere exposed to some radical-containing atmosphere. 相似文献
33.
34.
Hiroshi Ikeda 《Primates; journal of primatology》1982,23(3):338-347
Population changes and home range utilization of the wild Japanese monkey at Mt. Kawaradake have been studied since 1972.
Age compositions of this troop were obtained over a seven-year period. Troop size decreased from over 100 to 40 individuals
as a result of a capture in 1974.
The capture affected directly and indirectly the troop's range and population dynamics. The troop reduced its range size from
4.7 km2 to 2.67 km2 and changed its utilization pattern in relation to the decrease in size. After the capture, the troop used one particular
area intensively, whereas the rhythmic nomadic pattern had been observed as before. This may have been caused by the decrease
in the overall food requirement of the troop.
The birth rate increased significantly after the capture. However, troop size did not increase because of the low recruitment
rate for adult females and the high mortality of juveniles. 相似文献
35.
Summary A feedback resistant trp operon plasmid that transformed a multiple mutant (trpR tnaA) of Escherichia coli was found to enhance remarkably the production of tryptophan in a bench-scale fermentor. 5.5 g of tryptophan was accumulated per litre of culture medium at 24th hr in batch. The productivity was 0.229 g/l/hr. This productivity is the highest among those ever reported by other workers. The recombinant plasmid (Tcr Trp+ I-) used was completely stable in each run when tetracycline was added by 10 g/l into the medium. 相似文献
36.
Hiroshi Souzu 《生物化学与生物物理学报:生物膜》1980,603(1):13-26
Freeze-thawing of Escherichia coli cells caused a release of cell membrane components such as protein, phospholipids and lipopolysaccharides. A greater amount of release and a lesser extent of cell survival were seen in slow freeze-thawing than in rapid freeze-thawing. Several dehydrogenases in the cells were also freed. The mode of release was also dependent on the rate of freeze-thawing.The materials released by slow freeze-thawing were found to be mostly composed of outer membrane components, whereas the materials released by rapid freeze-thawing contained cytoplasmic as well as outer membrane components. The chemical composition of these fragments differed significantly from that of the original membranes. The relative content of cytoplasmic membrane-bound enzymes in these fragments also differed from that of the cytoplasmic membrane.The fragmentation was assumed to have resulted mainly from the crystallization of external water. In slow freeze-thawing, it was considered that the phase separation of the membrane phospholipid bilayer increased the possibility of outer membrane fragmentation. Rapid freeze-thawing caused cytoplasmic membrane damage to the cells as well as to the outer membrane. In rapid freeze-thawing, the effect of phase separation appeared to be small because of rapid passage through the transition temperatures.The presence of 10% glycerol completely inhibited the release of cellular materials and enzymes. Cell survival was maintained at a high level in the glycerol-treated samples whether freeze-thawed slowly or rapidly. 相似文献
37.
38.
Elisabetta Colletti Laura Frontali Claudio Palleschi Micheline Wesolowski Hiroshi Fukuhara 《Molecular & general genetics : MGG》1979,175(1):1-4
Summary In S. cerevisiae four isoacceptor mitochondrial tRNAs for serine have been separated by reversed phase chromatography. At least two of these species are products of different genes. In this work the deletion mapping technique has been used to locate two genes for tRNAser. The gene for tRNAser previously localized in the oli I region of the mitochondrial genome has been found to code for tRNA
ser
2
, and another gene coding for tRNA
ser
1
has been detected in the region where most of other tRNA genes are found. Results of fine mapping experiments allowed to localize this gene in the proximity of the gene for tRNAarg. 相似文献
39.
Protein I of Neisseria gonorrhoeae outer membrane is a porin 总被引:2,自引:1,他引:1
40.
The relationship between temperature and 2,6-dichlorophenolindophenol(DPIP) photoreduction activity in chloroplast fragments isolatedfrom spinach grown at different temperatures was investigatedin the temperature range from 25 to 25?C. Two break points in the slope of the Arrhenius plot of the Hillreaction were observed at 9 and 11?C in chloroplast fragmentsisolated from spinach grown at low temperatures (010?C).These breaks were not affected by an uncoupler. In chloroplastfragments from spinach grown in a higher temperature range (1030?C),only one break point was observed at 9?C. The other breakpoint at around 10?C appeared after treatment with detergent.Both break points were completely abolished by fixing the chloroplastfragments with glutaraldehyde. The break at around 10?C in chloroplast fragments isolated fromspinach grown at lower temperature was interpreted as due toacclimation rather than chilling sensitivity. (Received September 6, 1977; ) 相似文献