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1.
We have analyzed the mechanisms controlling the accumulation of cytotoxic/suppressor T lymphocytes in tumor tissues. We found that tumor-infiltrating helper/inducer T cells isolated from T-9 gliosarcoma-sensitized rats between 4 and 6 days after T-9 gliosarcoma inoculation produced a lymphocyte migration factor (LMF) during in vitro culture. Four peaks of LMF activity (A through D) were detected upon fractionation of LMF by using a Mono Q anion exchange column chromatography. Peak C exhibited the strongest activity among the four peaks of LMF. The action of peak C was chemotactic, but not chemokinetic. Peak C had an isoelectric point of 8.0 and a Mr of 26,000 Da. Only cytotoxic/suppressor T cells were found to be sensitive to peak C in vitro as well as in vivo. It is thus likely that peak C is responsible for the infiltration of cytotoxic/suppressor T cells into tumor tissues. The infiltration of lymphocytes into tumor tissues might also be regulated by the expression of lymphocyte sensitivity for LMF. The target molecule for LMF at 4 days may involve an asparagine-linked oligosaccharide. 相似文献
2.
Role of roots in differences in seed cadmium concentration among soybean cultivars—proof by grafting experiment 总被引:2,自引:0,他引:2
Soybean cultivars show significant differences in cadmium (Cd) concentrations in seeds, due primarily to genetics, not environmental
factors. We previously suggested that low-Cd cultivars accumulate Cd in their roots and thus prevent its translocation to
the rest of the plant. Through grafting experiments, we drew the following conclusions about Cd absorption and translocation:
(1) The amount of Cd accumulated in shoots is determined by the Cd accumulation capacity of roots: cultivars with a small
capacity to accumulate Cd in roots translocate more Cd and accumulate it in shoots; (2) The Cd concentration in shoots is
determined by the Cd accumulation capacity of roots and the shoot productive ability of the scion cultivar; (3) The Cd tolerance
of shoots differs among cultivars. Enrei, with a high-Cd accumulation capacity of roots, had a low Cd tolerance of shoots
compared with Suzuyutaka and Hatayutaka, with a low Cd accumulation capacity of roots; (4) Cultivars differ in their distribution
of Cd to seed; (5) These results show that seed Cd concentration is influenced by the differences among cultivars in ease
of translocation of Cd to seed and in Cd accumulation capacity of roots. 相似文献
3.
Noriharu Umetsu Jun Kaji Keiko Aoyama Kinjiro Tamari 《Bioscience, biotechnology, and biochemistry》2013,77(10):1867-1874
The occurence of tenuazonic acid (T.A.), which had been isolated from the culture broth of blast fungus, in blast-diseased rice plants was surveyed to ascertain whether or not this substance is one of the vivotoxins. T.A. was detected in four of six samples of blast-diseased rice plants, two of which had relatively high T.A. contents; 379 and 91 mg per kg of the samples (dry weight).Besides T.A., coumarin, o-coumaric acid and piricularin were also isolated from blast-diseased rice plants. The molecular formula of the last substance, which was tentatively presented in a previous paper, was corrected to C18H30N2O5 from the results of high resolution mass spectrometry. 相似文献
4.
T Murakami T Uede N Shijubo Y Torimoto T Ide K Sugimura I Azuma Y Takai K Kikuchi 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(12):4235-4242
Rat cytotoxic cell-generating factor (CGF) was purified from cell-free supernatants of a T cell hybridoma (6B2-B8) that constitutively produces CGF. CGF activity was assessed by its ability to generate cytotoxic cells against 51Cr-labeled T-9 cells from spleen cells of T-9-immunized rats. The purification scheme consisted of ammonium sulfate precipitation, AcA 54 gel permeation, Mono Q anion exchange chromatography, Superose 12HR 10/30 gel permeation, SDS-PAGE with subsequent electroelution, and ProRPC HR5/10 reverse phase column chromatography. Overall, CGF was purified approximately 13,000-fold, with a maximum 2.5% recovery of activity, and the sp. act. of the purified CGF was approximately 19,000 U/mg. The purified CGF is distinct from the other lymphokines such as IL-1, IL-2, IL-3, IL-4, T cell-replacing factor/IL-5, IL-6, and IFN-gamma. It is capable of promoting the generation of cytotoxic T cells from R1-10B5 (+) spleen cells of T-9-immunized rats and also stimulates a W3/25 (+) T cell hybridoma to express the IL-2R. The CGF has an apparent m.w. of 28,000 under non-reducing and 14,000 and 16,000 under reducing conditions. 125I-labeled CGF binds to normal thymocytes as well as splenic T cells. The highest level of binding of CGF was detected on splenic T cells derived from T-9-immunized rats that were previously shown to contain CTL precursors. The binding analysis with 125I-labeled CGF demonstrated that CGF binds to a specific cell surface molecule with an approximate m.w. of 60,000 to 70,000. 相似文献
5.
Keiya Ozawa Noriharu Sato Akio Urabe Fumimaro Takaku 《Biochemical and biophysical research communications》1984,123(1):128-132
The effects of retinoic acid (RA) on the proliferation and differentiation of normal myeloid progenitor cells (CFU-C) were studied. In general, RA at 10?10 to 10?6 M enhanced primary myeloid colony formation in the presence of colony-stimulating factor(s). However, macrophage colony formation was strongly inhibited by RA. This may be related to the finding that RA is able to differentiate bipotential HL-60 cells into granulocytes but not into macrophages. Moreover, secondary colony formation was always suppressed by the addition of RA to the primary cultures. It means that self-renewal capacity of CFU-C was suppressed by RA. This finding suggests that normal myelopoiesis will be suppressed eventually by RA. 相似文献
6.
Tetsuro Okabe Hitoshi Nomura Noriharu Sato Nakaaki Ohsawa 《Journal of cellular physiology》1982,110(1):43-49
In order to obtain human granulocytic colony-stimulating factor (G-CSF) in large quantities, a large-scale culture system of human G-CSF-producing cells has been established. The cell used for this system was T3M-1, which grew in a monolayered sheet in F-10 synthetic medium supplemented with 10% fetal bovine serum. T3M-1 cells grew in rolling bottles at the velocity of 0.5 r.p.m. with about 22 hr. of population doubling time. When the culture reached confluency, it was incubated in a serum-free medium supplemented with 1% bovine serum albumin. The conditioned medium was harvested every week, concentrated by Amicon PM-10 membrane, and loaded on a Sephadex G-75 column. The molecular weight of G-CSF was estimated at about 30,000. This G-CSF was stable over a pH range of 1.0 to 11.0 at 4°C for 21 hr. The CSF activity was destroyed by either trypsin or chymotrypsin, but resisted to RNase and DNase. A slight decrease in the activity was produced by treatment with neuramidase. G-CSF stimulated granulocytic colony formation of human and mouse marrow cells. By using the roller bottle culture system, we could obtain more than 100 liters of cultured medium in a month, which was able to form about 150,000,000 colonies of human bone marrow cells. The recovery of the human G-CSF activity from gel-filtration column was very high (91.7%), and a large increase of specific activity was obtainable (13.3-fold). This culture system is therefore expected to aid in the large-scale preparation of human G-CSF, thereby facilitating further studies on this granulopoietic factor. 相似文献
7.
8.
2,6-Dichlorobenzonitrile, a new cellulose-synthesis inhibitor,induced remarkable cell swelling and characteristic modificationof cell form in suspension cultured soybean. The cell form wasquite similar to that induced by coumarin, but was obviouslydifferent from that induced by colchicine.
1Present address: Department of Entomology, Division of Toxicologyand Physiology, University of California, Riverside, California92502, U.S.A. (Received April 10, 1976; ) 相似文献
9.
After instillation of 3H-dexamethasone into the eyes of a rabbit, 3H-9α-fluoro-11β-hydroxy-16α-methyl-1,4-androstadiene-3,17-dione was found in the aqueous humor. The same metabolite was also formed by incubating 3H-dexamethasone with the anterior ocular tissues of rabbit. Identification of 3H-9α-fluoro-11β-hydroxy-16α-methyl-1, 4-androstadiene-3, 17-dione was performed by its mobility on a thin layer plate and by proving its radiochemical homogeneity after recrystailization with the unlabeled sample which had been synthesized from dexamethasone by oxidation with sodium bismuthate.When dexamethasone disodium phosphate was instilled into rabbit's eyes, it was hydrolyzed to free dexamethasone and then metabolized to 9α-fluro-11β-hydroxy-16α-methyl-1, 4-androstadiene-3,17-dione. 相似文献
10.
Noriharu Umetsu Jun Kaji Kinjiro Tamari 《Bioscience, biotechnology, and biochemistry》2013,77(2):451-452
dl-(1245/36)-2,3,4,5,6-Pentachlorocyclohexanecarbonitrile was synthesized from (1234/ 56)-1,4,5,6-tetrachloro-2,3-epoxycyclohexane (α-BTC cis-epoxide). dl-(1245/36)-2,3,4,5,6-Pentachloro-1-methylcyclohexane was synthesized from the nitrile via dl-(1245/36)-2,3,4,5,6-pentachlorocyclohexylmethanol, the structure of which was confirmed by PMR spectroscopy using spin decoupling techniques and the shift reagent, Eu(DPM)3. This series of compounds was shown to have the same configuration as γ-BHC. The conformational equilibrium of these compounds is discussed. dl-(1245/36)-2,3,5,6-Tetrachloro-1,4-dimethyl-cyclohexane was synthesized by a stepwise route involving a Diels-Alder reaction of trans,trans-hexadiene-2,4 with maleic anhydride. 相似文献