Susumu Tsushima
Takeda Pharmaceutical Company
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Featured researches published by Susumu Tsushima.
Life Sciences | 1983
Zen-ichi Terashita; Susumu Tsushima; Yoshio Yoshioka; Hiroaki Nomura; Yoshiyuki Inada; Kohei Nishikawa
CV-3988, rac-3-(N-n-octadecylcarbamoyloxy)-2-methoxypropyl 2-thiazolioethyl phosphate was shown to be a specific inhibitor of platelet activating factor (PAF). This compound in concentrations of 3 x 10(-6) to 3 x 10(-5)M inhibited aggregation of rabbit platelets induced by PAF (3 x 10(-8)M), while it had no effect on the aggregation induced by arachidonic acid, ADP, collagen or A-23187. CV-3988 alone even at a concentration of 10(-3)M had no effect on platelet aggregation. The inhibitory action of CV-3988 on the PAF-induced aggregation was independent of the formation of micelles. The PAF (0.1 to 1.0 micrograms/kg, i.v.)-induced hypotension in anesthetized rats was also inhibited dose-dependently by the i.v. administration of CV-3988 (1 and 10 mg/kg), while the hypotensive actions induced by the i.v. administration of acetylcholine (1 micrograms/kg), arachidonic acid (1 mg/kg), bradykinin (10 micrograms/kg), isoproterenol (1 microgram/kg) and histamine (100 micrograms/kg) were not altered by CV-3988 (10 mg/kg, i.v.). All these findings indicate that CV-3988 specifically inhibits the action of PAF in vitro and in vivo. This is the first report of a PAF antagonist which can specifically inhibit the PAF-induced hypotension as well as the PAF-induced platelet aggregation.
European Journal of Cancer and Clinical Oncology | 1983
Yoshio Honma; Yuko Fujita; Takashi Kasukabe; Motoo Hozumi; Kazumi Sampi; Masaharu Sakurai; Susumu Tsushima; Hiroaki Nomura
Leukemia cells from patients with acute non-lymphocytic leukemia were treated with various inducers of differentiation of the human promyelocytic leukemia cell line HL-60. All cells in 14 specimens tested underwent morphological, functional and histochemical changes after treatment with some inducers of differentiation of HL-60 cells, but the most effective inducer varied for different specimens. These results suggest that treatment with some inducers should be effective for inducing most acute myeloid leukemia cells to differentiate into morphologically and functionally mature granulocytes and macrophages.
Cancer Chemotherapy and Pharmacology | 1983
Yoshio Honma; Takashi Kasukabe; Junko Okabe-Kado; Motoo Hozumi; Susumu Tsushima; Hiroaki Nomura
SummaryVarious alkyl ethyleneglycophospholipids, i.e., alkyl phospholipids, with ethyleneglycol or its congener in place of glycerol as a molecular backcone, were synthesized and their effects on cell proliferation and differentiation of cultured human (HL-60) and mosue (Ml) myeloid leukemia cells were studied. On incubation with alkyl ethyleneglycophospholipids, proliferation of both cell lines was inhibited and the cells were induced to differentiate into morphologically and fuctionally mature granulocytes and macrophages. Among the compounds tested, dodecyl ethyleneglycophospholipid with a pyridinioethyl group was the most effective in induction of differentiation of both cell lines.
Cancer Immunology, Immunotherapy | 1987
Mikihiko Naito; Ichiro Kudo; Yukiko Mukai-Sato; Susumu Tsushima; Hiroaki Nomura; Shoshichi Nojima; Keizo Inoue
SummaryLiposomes composed of chemically synthesized glyceroglycolipids, such as 1,2-dipalmityl-[β-cellobiosyl-(1′ → 3)]-glycerol (Cel-DAG), 1,2-dipalmityl-[β-lactosyl-(1′ → 3)]-glycerol, or 1,2-dipalmityl-[β-maltosyl-(1′ → 3)]-glycerol, were found to enhance protective immunity against transplantable tumor cells (sarcoma 180) in ICR mice. Peritoneal exudate cells prepared from mice treated in vivo with Cel-DAG showed cytostatic activity in vitro against the mouse leukemia cell line, EL-4. Adherent cells separated from this preparation showed similar activity. Peritoneal cells from polypeptone-injected mice acquired appreciable cytostatic activity when incubated in vitro in the presence of glyceroglycolipid liposomes. The adherent cell fraction alone showed rather weak cytostatic activity when pretreated with the glyceroglycolipids, and full activity was restored by supplementing with the nonadherent cell fraction. The ability of glycolipids to induce tumoricidal effects was affected by cholesterol content: with increasing cholesterol content, the activities decreased. Cholesterol-free glycolipid liposomes were taken more efficiently by macrophages than cholesterol-containing liposomes. Cholersterol modifies the surface property of glyceroglycolipid liposomes. Activation of macrophages is responsible for enhancement of protective immunity against tumor cells by injection of these glycolipids in vivo.
Journal of The Chemical Society D: Chemical Communications | 1969
Michio Yoshida; Hirosada Sugihara; Susumu Tsushima; Takuichi Miki
When 1-arylbut-3-enyl acetates were flashed through a quartz tube at 500–900°, a Cope reaction occurred to give the cyclized compounds and in two cases unexpected isomerization was observed.
Cancer Research | 1981
Yoshio Honma; Takashi Kasukabe; Motoo Hozumi; Susumu Tsushima; Hiroaki Nomura
Archive | 1990
Hiroaki Nomura; Kohei Nishikawa; Susumu Tsushima
Journal of Biochemistry | 1985
Hidetoshi Hayashi; Ichiro Kudo; Keizo Inoue; Kikuo Onozaki; Susumu Tsushima; Hiroaki Nomura; Shoshichi Nojima
Archive | 1981
Motoo Hozumi; Susumu Tsushima; Yoshio Yoshioka
Cancer Chemotherapy and Pharmacology | 1983
Yoshio Honma; Takashi Kasukabe; Junko Okabe-Kado; Motoo Hozumi; Susumu Tsushima; Hiroaki Nomura