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1.
Kiyoshi Takahashi Katsuya Miyatani Hiroyuki Yanai Ho Jong Jeon Kotaro Fujiwara Tadashi Yoshino Kazuhiko Hayashi Tadaatsu Akagi Ken Tsutsui Koichi Mizobuchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,62(1):105-113
Monocytic leukemia (MoL) cells were obtained from the peripheral blood of a patient in whom the leukemic cells infiltrating
various lymphoreticular organs exhibited features intermediate between interdigitating reticulum cells (IDC) and ordinary
phagocytic macrophages, whereas the leukemic cells in the peripheral blood were essentially monocytic and lacked such features.
Peripheral blood CD4+ T-cells were established as an interleukin-2-dependent T-cell line. When the MoL cells were exposed
for a few days to conditioned medium from the T-cell line, they extended several dendritic cytoplasmic projections and became
intensely positive for HLA-DR antigen, cytoplasmic S-100β protein, and CD1 antigen. Functionally, the conditioned medium significantly
down-regulated Fc-mediated and Fc-independent phagocytic activities, and the levels of lysosomal enzymes such as lysozyme
and nonspecific esterase in the MoL cells. Moreover, the conditioned medium significantly up-regulated the accessory cell
function of the MoL cells as measured by the primary allogenic mixed leukocyte reaction (MLR). Furthermore, the conditioned
medium significantly down-regulated the expression of CD14 antigen.
Biochemical analysis indicated that the factor responsible for these changes is a protein which is distinct from known human
cytokines and whose molecular weight is approximately 31 kDa. These findings suggest that IDC are closely related the monocytic
lineage and that helper T-cells play an important role in constructing the microenvironment of T-lymphoid tissues which is
necessary for the differentiation and maturation of IDC. 相似文献
2.
Sadaaki Iwanaga Takashi Morita Toshiyuki Miyata Takanori Nakamura Jun Aketagawa 《Journal of Protein Chemistry》1986,5(4):255-268
A hemocyte lysate from horseshoe crab produced a gel, when exposed to Gram-negative bacterial endotoxins. This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that there is a (1 3)--d-glucan-mediated coagulation pathway which also results in the formation of gel. Up to now, six protein components, designated coagulogen, proclotting enzyme, factor B, factor C, factor G and anti-LPS factor, all of which are closely associated with the endotoxin-mediated coagulation pathway, have been purified and biochemically characterized. Among these components, the complete amino acid sequences of coagulogens isolated from one American and three Asian species of horseshoe crabs have been established. Moreover, the reconstitution experiment using the isolated clotting factors, C, B, proclotting enzyme and coagulogen in the presence of endotoxin, leads to the formation of coagulin get. Based on these results, we propose here a mechanism for the Limulus coagulation cascade. 相似文献
3.
4.
On cell proliferation and differentiation of the fundic mucosa of the golden hamster 总被引:1,自引:0,他引:1
Takanori Hattori 《Cell and tissue research》1974,148(2):213-226
5.
Isolated microspores of Chinese cabbage (Brassica campestris ssp. pekinensis) were incubated in modified NN medium containing 10% sucrose in darkness at 33°C for one day followed by culture at 25°C. After 14 days of culture, microspores developed into embryos ranging from globular to cotyledonary stage. Plants were regenerated after transfer of embryos to medium containing 3% sucrose and no plant growth regulators.Abbreviations NN
Nitsch and Nitsch
- MS
Murashige and Skoog
- NAA
naphthaleneacetic acid
- BA
6-benzylaminopurine 相似文献
6.
Microsatellite DNA markers for rice chromosomes 总被引:45,自引:1,他引:44
H. Akagi Y. Yokozeki A. Inagaki T. Fujimura 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(7):1071-1077
We found 369 complete microsatellites, of which (CGG/GCC)n was the most frequent, in 11 798 rice sequences in the database. Of these microsatellites, 35 out of 45 could be successfully converted into microsatellite DNA markers using sequence information in their flanking regions. Thus, the time and labor used to develop new microsatellite DNA markers could be saved by using these published sequences. Twenty eight polymorphic markers between Asominori (japonica) and IR24 (indica) have been correctly mapped on the rice genome and microsatellites appear to be randomly distributed in the rice chromosomes. Integration of these markers with the published microsatellite DNA markers showed that about 35% of the rice chromosomes were covered by the 56 microsatellite DNA markers. These microsatellites were hypervariable and were easily to assay by PCR; they were distributed to all chromosomes and therefore, one can easily select plants carrying desired chromosome regions using these microsatellite DNA markers. Thus, microsatellite maps should aid the development of new breeds of rice saving time, labor, and money. 相似文献
7.
Inactivation of bleomycin by an N-acetyltransferase in the bleomycin-producing strain Streptomyces verticillus 总被引:1,自引:0,他引:1
Masanori Sugiyama Takanori Kumagai Mitsuhiko Shionoya Eiichi Kimura Julian E. Davies 《FEMS microbiology letters》1994,121(1):81-85
Abstract Bleomycin-producing Streptomyces verticillus ATCC15003 possesses a bleomycin acetyltransferase which inactivates the drug in the presence of acetyl coenzyme A. The site of acylation in enzymically prepared acetylbleomycin A2 was determined by nuclear magnetic resonance analysis; the primary amino group of the β-aminoalanine moiety of bleomycin was acetylated. Acetylbleomycin A2 had no detectable antibacterial activity and did not induce in vitro DNA degradation. 相似文献
8.
Zhao Ying Hiromasa Tojo Takanori Komatsubara Manabu Nakagawa Masami Inada Sumio Kawata Yuji Matsuzawa Mitsuhiro Okamoto 《生物化学与生物物理学报:疾病的分子基础》1994,1226(2):201-205
Enzyme activity, protein contents, and mRNA contents of group II phospholipase A2 (PLA2) in hepatocellular carcinoma (HCC) surgically obtained from 8 patients were compared with those in either its neighboring liver tissues or control liver tissues. The PLA2 specific activity towards the mixed micelles of 1-palmitoyl-2-oleoyl-phosphatidylglycerol and cholate was significantly greater in the tumor tissues (6.62 ± 1.46 nmol/min/mg) than those in the surrounding liver tissues (1.33 ± 0.22 nmol/min/mg) and controls (0.43 ± 0.04 nmol/min/mg). The results of immunoblot analysis using a specific anti-human group II PLA2 antibody and of Northern blot analysis using a human group II PLA2 cDNA as a probe demonstrated that group II PLA2 was responsible for the increased enzyme activity. The contents of immunoreactive group II PLA2 in the tumor tissues (8.81 ± 1.24 ng/mg) were significantly higher than those in the surrounding liver tissues (1.77 ± 0.27 ng/mg); those in the control tissues were below the analytical range of the method used. The group II PLA2 mRNA was also significantly increased in the tumor tissues, compared with that in the surrounding liver tissues, whereas it was not detectable in th controls. This indicates that group II PLA2 in HCC is induced at the pretranslational level. 相似文献
9.
Serum-free culture of rat keratinocytes 总被引:2,自引:0,他引:2
Hirosuke Oku Chikara Kumamoto Tomoyuki Miyagi Takanori Hiyane Junichi Nagata Isao Chinen 《In vitro cellular & developmental biology. Animal》1994,30(8):496-503
Summary Procedures for the serum-free culture of rat keratinocytes have been established. Basal cells prepared from epidermis of newborn
rat were stored in liquid nitrogen and used for primary culture. Among the available media, MCDB 153, developed originally
for human keratinocyte (HK) culture, was the best for the development of serum-free formulation. To grow rat keratinocytes,
bovine serum albumin was arbitrarily substituted for the macromolecule supplements needed for HK culture, i.e. fetal bovine
serum protein or bovine pituitary extract. Qualitative and quantitative adjustment of supplements was thereafter made to support
rapid cell growth. Satisfactory cell growth was achieved in the optimized medium of MCDB 153 supplemented with growth factors
and amino acids: insulin (10 μg/ml), hydrocortisone (0.1 μg/ml), epidermal growth factor (25 ng/ml), calcium chloride (0.2
mM), histidine (0.23 mM), isoleucine (0.05 mM), tryptophane (0.015 mM), threonine (1.25 mM), tyrosine (0.031 mM), alanine (4.08 mM), and albumin (2 mg/ml). This optimized culture system was superior to the original HK culture condition for rapid growth
of rat keratinocytes. Under our condition, cells grew as a monolayer, becoming confluent, but without stratification, and
were passaged 2 to 3 times without any changes in morphology. The serum-free formulation allows us to control more accurately
the concentrations of biomolecules in the medium including lipids and hormones, and therefore will be suitable for the study
focusing on lipid metabolism or hormonal regulation of rat keratinocytes. 相似文献
10.