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N Takemoto

Publications and source records attributed to N Takemoto.

At least 55 records · Page 3Linked to original sources
PubMed1992

Retinoic acid enhances the secretion of plasminogen from cultured rat microglia.

To determine the amount of plasminogen in microglial conditioned medium, a highly sensitive and specific enzyme-linked immunosorbent assay (ELISA) for rat plasminogen was established. Weak cross-reactivity with human serum plasminogen was observed, while no reactivity was detected with frog and carp plasminogen. The specificity of the immunosorbent assay was confirmed by Western blotting. The secretion of plasminogen into the microglial culture medium was quantified by using the established ELISA and was found to be increased depending on the culture time and number of microglia. The secretion was increased about 5-fold by stimulation with retinoic acid, while interleukin-1, and basic fibroblast growth factor showed no significant effect.

Animals↗
PubMed1992

Production and secretion of plasminogen in cultured rat brain microglia.

The production and secretion of plasminogen in cultured rat brain microglia was investigated. Urokinase-dependent caseinolytic activity was detected by zymography in microglial conditioned medium with a molecular weight of about 90 kDa. The 90-kDa protein was also detected by Western blotting with anti-rat plasminogen antiserum in the non-reducing condition. Immunoprecipitation with plasminogen antiserum following [35S]methionine labelling revealed that the plasminogen detected in microglial conditioned medium is synthesized in microglia. The amount of plasminogen in the conditioned medium was increased by stimulation with lipopolysaccharide. These results show that cultured microglia produce plasminogen and secrete it into the culture medium.

Animals↗
PubMed1992

Mitogenic and complement activating activities of the herbal components of juzen-taiho-to.

The Kampo (Japanese herbal) medicine "Juzen-Taiho-To" (TJ-48), which was prepared by decocting a concoction (formula), contains ten kinds of herbs and has several immunostimulating activities. In order to determine the contribution of each herbal component, the complement-activating and mitogenic activities of the hot water extract as well as the polysaccharide fraction from each herb were tested. Hot water extracts of Glycyrrhizae radix, Astragali radix, and Atractylodes lanceae rhizoma showed significant mitogenic activity whereas that of Cinnamomi cortex showed potent complement-activating activity. However, the exclusion of any single component herb whether active or not on its own did not result in a loss or an increase of the overall activity of TJ-48. The polysaccharide fraction from Glycyrrhizae radix showed the most potent of both activities among the same fractions from the other nine herbs, and reduced both activities after periodate oxidation, thus indicating that the carbohydrate moiety may contribute to both activities.

Animals↗
PubMed1992

Six new triterpenoidal glycosides including two new sapogenols from Albizziae Cortex. V.

Six new triterpenoid glycosides called julibrosides A1-A4, B1 and C1 were isolated from Albizziae Cortex, the dried stem bark of Albizzia julibrissin Durazz. Their structures were determined based on spectral and chemical evidence. Julibrosides B1 and C1 had new sapogenols, designated julibrogenin B and C, respectively, while julibrosides A3 included N-acetyl-D-glucosamine as a sugar component.

Carbohydrate Sequence↗
PubMed1992

[Endoscopic treatment of early gastric cancer].

We assessed the results of endoscopic resection (ER) of early gastric cancer using electrocoagulation with high frequency current. Resection was performed utilizing endoscopic double-snare polypectomy (EDSP) and electrocoagulation. The initial endoscopic total resection rate was 65.0% (119/183 lesions). There were 32 lesions in which no residual cancer was present at follow-up biopsy or surgery, and when these were included the endoscopic resection cure rate was 82.5%. Extensive tissue necrosis and degeneration occurred in the resected stump as a result of using electrocoagulation. Since an increase in suitable patients and an expansion of the indications for endoscopic resection are anticipated in the future, careful clinical evaluation of endoscopic resection based on the results of pathological assessment of the resected tissue is needed.

Electrocoagulation↗
PubMed1991

Heterogeneity and characterisation of mitogenic and anti-complementary pectic polysaccharides from the roots of Glycyrrhiza uralensis Fisch et D.C.

Two anti-complementary polysaccharide fractions (GR-2IIa and GR-2IIb), isolated from the roots of Glycyrrhiza uralensis Fisch et D.C., each gave five anti-complementary polysaccharides (GR-2IIa-1-5 and GR-2IIb-1-5) on h.p.l.c.; likewise, GR-2IIc gave two anti-complementary and mitogenic polysaccharides (GR-2IIc-1-2A and -2IIc-2) by gel filtration and h.p.l.c. GR-2IIc-1-2A showed the most potent anti-complementary activity. GR-2IIa-1-5 and GR-2IIb-1-5 contained 40-85% and 50-90% of GalA, respectively, in addition to Rha, Ara, and Gal. GR-2IIc-1-2A and -2IIc-2 mainly comprised Glc, Gal, GalA, and GlcA in addition to Rha, Fuc, Xyl, Ara, and Man. Methylation analysis and digestion with endo-alpha-(1----4)-polygalacturonase indicated that all of the polysaccharides contained polygalacturonan regions which were frequently methyl-esterified. GR-2II-a, -2IIb, and -2IIc gave enzyme-resistant fractions of large and intermediate sizes, in addition to oligogalacturonides. Each large fraction from GR-2IIa and -2IIb consisted mainly of Ara, Gal, and GalA, whereas the intermediate fractions were composed of small proportions of 2-Me-Fuc, 2-Me-Xyl, and apiose (Api), in addition to Rha, Ara, Gal, and GalA. The large fraction from GR-2IIc mainly contained Rha, Man, Gal, and GalA in addition to Fuc, Ara, Xyl, and Glc, whereas the intermediate fraction consisted of 2-Me-Fuc, 2-Me-Xyl, and Api, in addition to Rha, Ara, GalA, Fuc, Xyl, Man, Gal, and Glc. Base-catalysed beta-elimination followed by ethylation indicated that all the polysaccharides except GR-2IIc-2 contained a 4-linked uronic acid attached to position 2 of 2,4-linked Rha. Single radial gel diffusion, using the beta-D-glucosyl-Yariv antigen, indicated that GR-2IIa-1 and GR-2IIc-2 contained relatively large proportions of (1----3,6)-beta-D-galactan moieties. The anti-complementary activities of GR-2IIa-3, GR-2IIa-4, and GR-2IIb-4 decreased after de-esterification followed by digestion with endo-alpha-(1----4)-polygalacturonase. The large fractions from GR-2IIa-2IIc showed more potent anti-complementary activities than the original polysaccharide fractions, whereas the intermediate fractions and oligogalacturonides were inactive. The large fraction from GR-2IIc had more potent mitogenic activity than GR-2IIc, whereas the intermediate fraction and oligogalacturonides from GR-2IIc were inactive.

Adjuvants, Immunologic↗
PubMed1991

Characterization of mitogenic pectic polysaccharides from kampo (Japanese herbal) medicine "juzen-taiho-to".

The acidic polysaccharide fraction (F-5-2) from "Juzen-Taiho-To" (TJ-48), a Kampo (Japanese herbal) medicine prepared by decocting a prescription of 10 kinds of herbs, has potent mitogenic activity. In order to clarify the mitogenic activity, F-5-2 was fractionated by amon-exchange chromatography, and 14 acidic polysaccharide fractions were obtained. Mitogenic activities of these polysaccharides were increasing with their molecular masses and affinities to the anion-exchange column. Methylation analysis and endo-alpha-(1----4)-polygalacturonase digestion showed these polysaccharide fractions to be pectic polysaccharides, many of which consisted mainly of polygalacturonan regions in addition to small amounts of "ramified" regions. Gel filtration showed that the molecular masses of the "ramified" regions of the polysaccharides were similar. High molecular mass polygalacturonic acid showed a weak mitogenic activity. The mitogenic (M-1 and M-2) and non-mitogenic (M-3) polysaccharides from the most active polysaccharide fraction (F-5-2IIh) were further purified by gel filtration. M-2 and M-3 were also shown to be pectic polysaccharides, and the neutral glycosidic linkages in M-2 and M-3 were different from each other. Endopolygalacturonase digestion markedly decreased the mitogenic activity of M-2, however, the "ramified" region of M-2 still showed a weak activity.

Animals↗
PubMed1990

Fractionation and characterization of mitogenic and anti-complementary active fractions from kampo (Japanese Herbal) medicine "juzen-taiho-to".

"Juzen-Taiho-To" (TJ-48), which is a kampo (Japanese herbal) medicine prepared by decocting a prescription of ten kinds of herbs, has several immunostimulating activities. In order to characterize the active substances for anti-complementary and mitogenic activities, TJ-48 was fractionated. Anti-complementary activity was observed in the water- and methanol-insoluble fraction (F-2) and the crude polysaccharide fraction (F-5), whereas mitogenic activity was only found in F-5. However, other low molecular mass fractions did not show both activities. Methylation analysis indicated that F-2 mainly contained amylopectin-like polysaccharides. Both Pronase digestion and periodate oxidation decreased the anti-complementary activity of F-2, and the beta-amylase-resistant fraction of F-2 still retained the potent anti-complementary activity. When F-5, which has the most potent of both activities, was further fractionated, only the major acidic polysaccharide fraction, F-5-2, showed potent mitogenic activity. Endo-alpha-(1----4)-polygalacturonase digestion showed that F-5-2 mainly contained pectic polysaccharides, and the endo-polygalacturonase treatment of F-5-2 reduced the mitogenic activity but not the anti-complementary activity. F-2 and F-5 each activated the complement system by a different mode of action.

Animals↗
PubMed1989

Plantagoside, a novel alpha-mannosidase inhibitor isolated from the seeds of Plantago asiatica, suppresses immune response.

A hot-water extract from the seed of Plantago asiatica showed a potent inhibitory activity against jack bean alpha-mannosidase, and a flavanone glucoside, plantagoside, was isolated as the inhibitor. Plantagoside was a specific inhibitor for jack bean alpha-mannosidase (IC50 at 5 microM) and appeared to be a non-competitive inhibitor of the enzyme. Whereas, negligible or weak inhibitory activities were observed for beta-mannosidase, beta-glucosidase, and sialidase tested. Plantagoside also inhibited alpha-mannosidase activities in mouse liver lysosomal and microsomal fractions, and the enzyme inhibitory activity in microsomal fraction was enhanced in the presence of glucosidase inhibitor, castanospermine. Plantagoside suppressed antibody response to sheep red blood cells and concanavalin A induced lymphocyte proliferation which was measured by [3H]thymidine incorporation.

Animals↗
PubMed1985

Studies on responsiveness of hepatoma cells to catecholamines. II. Comparison of beta-adrenergic responsiveness of rat ascites hepatoma cells with cultured normal rat liver cells.

The pharmacological properties of beta-adrenoceptors in rat ascites hepatoma cells were compared with those in normal rat liver cells which were cultured for 24 hr after collagenase digestion. Adenylate cyclases in the homogenates of cultured normal rat liver cells and rat ascites hepatoma cells, AH44, AH66, AH109A, AH130 and AH7974, were all activated by isoproterenol or NaF to different degrees. The enzyme in rat liver cells was activated by several beta 2-agonists but those in all hepatoma cells hardly responded. Furthermore, salbutamol, a beta 2-partial agonist, antagonized the cyclase activation by isoproterenol in AH130 cells. The Kact value of isoproterenol for the activation of adenylate cyclase in AH130 cells was smaller than that in rat liver cells. A comparison of the Ki values of beta-antagonists for the inhibition of isoproterenol-stimulated cyclase activity shows that while the Ki values of propranolol and butoxamine in AH130 cells were similar to those in rat liver cells, a significant difference was observed in the values for beta 1-selective antagonists between AH130 cells and rat liver cells. The Ki values of metoprolol and atenolol for AH130 cells were 137- and 90-fold lower, respectively, than for normal rat liver cells. From these findings, it is strongly suggested that beta-adrenoceptors in rat ascites hepatoma cells including AH130 cells have similar properties to the mammalian beta 1-receptor.

Adenylyl Cyclases↗
PubMed1984

Studies on responsiveness of hepatoma cells to catecholamines. I. Lack of beta-adrenergic responsiveness in rat ascites hepatoma AH13 cells.

The beta-adrenoceptor density and the activities of adenylate cyclase and cyclic AMP phosphodiesterase were examined to compare AH13 cells having lower beta-adrenergic responsiveness with other rat ascites hepatoma cells and normal rat liver cells. Normal rat liver cells used were cultured for 24 hr after the collagenase digestion of liver. The density of binding sites of 3H-dihydroalprenolol in AH13 cell plasma membrane was very similar to the density in AH44 and normal liver cell membrane, but that in AH130 cell plasma membrane was about 10-fold greater than those in the other three cell lines. The activity of cyclic AMP phosphodiesterase was about 2.5- to 7-fold higher in hepatoma cells than in rat liver cells, but this enzyme activity of AH13 cells was not especially high among the hepatoma cells examined. The basal adenylate cyclase activity was lower in AH44 cells, but was higher in AH13 and AH130 cells than in rat liver cells. However, adenylate cyclase of AH13 cells was hardly activated by isoproterenol, while the enzyme of the other cells was activated 3- to 5-fold. On the other hand, adenylate cyclase of each cell line including AH13 was activated 4- to 14-fold by NaF. From these results, it is suggested that AH13 cells can hardly produce cyclic AMP by the beta-adrenergic stimulation because of the disordered interaction of beta-adrenoceptors with adenylate cyclase.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1982

Hepatocellular carcinoma presenting as intrabile duct tumor growth: a clinicopathologic study of 24 cases.

We describe the features of 24 cases of hepatocellular carcinoma (HCC) with prominent intrabile duct tumor growth seen among 238 autopsy and 21 surgical cases of HCC. Progressive obstructive jaundice occurred during the course of most cases and was the presenting sign in nine. A fluctuating rise and fall of the total bilirubin was seen in two cases. The average survival time of the cases was significantly shorter than that of HCC patients without intrabile duct tumor growth (Mann-Whitney's U-test, one-tailed, P less than 0.05). The average survival time after the development of severe jaundice (total bilirubin over 10 mg/dl) was only 16 days. Intrabile duct tumor casts were located in the hepatic and/or the common bile ducts in 19 cases (79%) and in five cases were seen in the peripheral (medium to small-sized) bile ducts. Hemobilia developed in five cases (21%) and was regarded as the immediate cause of death in one. Grossly all the cases presented infiltrative or mixed (infiltrative and nodular) growth pattern. Intrabile duct tumor growth and associated marked obstructive jaundice may frequently herald the terminal phase of HCC in certain patients. In our series, approximately 40% of patients with HCC and significant jaundice had gross evidence of extensive intraductal tumor growth. In the absence of intraductal tumor growth, jaundice in HCC usually was seen in a setting of progressive terminal hepatic failure.

Adult↗
PubMed1982

Histologic growth pattern of hepatocellular carcinoma: relationship to orcein (hepatitis B surface antigen)-positive cells in cancer tissue.

The histologic pattern of tumor growth at tumor-nontumor boundaries was studied in 60 livers bearing hepatocellular carcinoma. Three growth patterns, arbitrarily described as "sinusoidal," "replacing," and "encapsulated," were distinguished. Cancer cells growing in the sinusoids between liver cell cords (sinusoidal pattern) were anaplastic; those growing in an expansile fashion and acquiring a fibrous capsule (encapsulated pattern) were most differentiated; and those growing into the cord of liver cells and replacing them (replacing pattern) were differentiated to an intermediate degree. There was certain relation between the histologic growth patterns and gross morphologic features of the tumors. Test results for 20 of the 60 cases were positive for serum hepatitis B surface antigen (HBsAg), and the livers also contained orcein-positive cells. Orcein-positive cells were frequently seen at the border between tumor and parenchyma. Cells containing HBsAg as an orcein-positive inclusion were present in cancer tissue in three cases. When serial sections were made from such areas and stained alternately with hematoxylin and eosin and orcein, it was found that these cells were hepatocytes blended with cancer cells. This phenomenon was related to the growth pattern of tumor cells. Orcein-positive cells were never found in metastatic lesions.

Adult↗
PubMed1975

Inhibition of dopamine beta-hydroxylase in blood vessels by picolinic acid derivatives in vivo and their anthypertensive effects.

The effect of picolinic acid derivatives, 5-butylpicolinic (fusaric) acid (FA), 5-(3',4'-DIBROMOBUTYL)PICOLINIC ACID(BPR2FA)and 50(N'N-dimethyldithiocarbamoilmethyl)picolinic acid (YP-279) on dopamine beta-hydroxylase in blood vessels in vivo was studied. Maximum inhibition of the conversion of 14C-dopamine (14C-DA) to 14C-norepinephrine (14C-ne) in rat aorta, mesenteric artery and renal artery was detected 30 min after FA and Br2FA (75 mg/kg) and 60 min after YP-279 (75 MG/KG). NE synthesis from 14C-DA returned to near control values by 6 hr in the blood vessels. NE levels of the aorta and mesenteric artery were sigkificantly reduced by 30 to 50% at 4 hr after Br2FA or FA (75 mg/kg). Dopamine beta-hydroxylase (DBH) activity, using tyramine as substrate, in heart, aorta, mesenteric artery and renal artery was markedly reduced. The concentrations of FA, Br2FA and YP-279 in rat blood following a single i.p, injection of each drug increase rapidly, reaching highest values in 0 to 30 min and decreasing slowly to 0 after 6 hr. These compounds did not affect the uptake of 3H-NE into the rat heart. These three compounds were found to lower blood pressure effectively in normal Wistar rats (above 25 mg/kg).

Animals↗