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T Ueda

Publications and source records attributed to T Ueda.

At least 1,153 records · Page 64Linked to original sources

Serotonin as a major serum factor inducing the phospholipase C-mediated hydrolysis of phosphoinositides in normal rat kidney cells.

Calf serum induced the phospholipase C-mediated hydrolysis of phosphoinositides in normal rat kidney (NRK) cells transformed by a temperature-sensitive Kirsten murine sarcoma virus (tsK-NRK cells). Various growth factors known to induce the phospholipase C reactions in other cell types, such as platelet-derived growth factor, fibroblast growth factor, epidermal growth factor, thrombin, vasopressin, bombesin, cholecystokinin, and prostaglandin F2 alpha, did not induce phospholipase C reactions in the transformed NRK cells. Furthermore, noradrenaline, histamine, dopamine, angiotensin II, carbachol, and tumor growth factor-beta did not induce phospholipase C reactions. However, serotonin did induce phospholipase C reactions. The amount of serotonin contained in the calf serum was sufficient to support 50% of the activity promoted by the serum itself, and calf serum-induced phospholipase C reactions were inhibited to 10-20% of the original level by ketanserin and methysergide, known to be antagonists for the serotonin receptors. Dialysis almost completely removed serotonin from calf serum and reduced the serum-induced phospholipase C reactions. Moreover, the phospholipase C reactions induced by calf serum and serotonin were inhibited by pretreatment of the cells with pertussis toxin or 12-O-tetradecanoylphorbol-13-acetate. These results indicate that serotonin is one of the major serum factors inducing phospholipase C-mediated hydrolysis of phosphoinositides in transformed NRK cells. Serotonin induced phospholipase C reactions not only in tsK-NRK cells but also in nontransformed NRK cells. However, serotonin did not induce these reactions in Swiss 3T3 cells or NIH 3T3 cells.

Adenosine Diphosphate Ribose↗

Multivariate analysis for clinical prognostic factors in 163 patients with soft tissue sarcoma.

Clinical and histologic findings in 163 patients with localized soft tissue sarcoma (STS) in the extremities and trunk were reviewed. There were 91 male patients and 72 female patients ranging in age from 2 to 84 years (median, 46 years). The histologic status of the tumors was as follows: low grade, 29 cases; intermediate grade, 52 cases; and high grade, 82 cases. The primary tumors were treated by intralesional excision (two cases), marginal (88), wide local (52), or amputation (21). Subsequent adjuvant therapy was given to 61 patients; 17 had radiotherapy (RT), 27 had chemotherapy (CH), and 17 had combined RT and CH. The overall survival (P less than 0.1) and disease-free survival (P less than 0.001) were better in the group that received multimodal treatment (radical surgery and adjuvant chemotherapy with or without radiotherapy) than in the group treated only by surgery. This suggests the favorable role of adjuvant therapy. The univariate and the Cox multivariate analysis for prognosis revealed that sex, tumor-related symptoms, tumor size, tumor depth, and histologic grade were the significant factors. Among the treatment schemes, adjuvant chemotherapy was the only one that affected survival, especially for the intermediate-grade tumors. Initial surgical treatment (marginal versus wide local excision) significantly contributed to the local control of the primary tumors.

Actuarial Analysis↗

Multivariate analysis for histologic prognostic factors in soft tissue sarcomas.

To investigate histologic prognostic factors in soft tissue sarcomas (STS), multivariate analysis was performed on 236 patients with complete clinical information. These included 141 males and 95 females with an age range from 1 to 85 years (median, 47.6 years). Histologically, malignant fibrous histiocytoma (33.5%) was the most common type followed by synovial sarcoma (11%), liposarcoma (10%), rhabdomyosarcoma (7%), and leiomyosarcoma (7%). Monofactorial analysis revealed that sex, depth, location, histologic grade, cellularity, frequency of mitosis, and necrosis were significant prognostic factors. By multivariate analysis, only frequency of mitosis and depth of tumors were proved to be of prognostic significance. The prognostic importance of the frequency of mitosis as shown in previous and the present studies indicates that further investigation of the cell proliferation in patients with STS is required.

Age Factors↗

Guanine nucleotide-induced Ca2+ release in permeabilized murine thymocytes.

GTP and IP3 induced Ca2+ release from an internal store in permeabilized murine thymocytes loaded with Ca2+ by ATP. Ca2+ release was dependent on the concentration of GTP: half-maximal release with 0.5 microM and maximal release with 10 microM. The GTP effect was completely abolished by 100 microM GTP gamma S, GMPPNP and UTP. None of the other nucleotides used except ITP induced Ca2+ release. When GTP was added after the effect of IP3 had virtually subsided, and vice versa, further Ca2+ release occurred, which led to the conclusion that the mechanism of GTP-mediated Ca2+ release may be different from that of IP3-mediated release.

Animals↗

A novel lysine-substituted nucleoside in the first position of the anticodon of minor isoleucine tRNA from Escherichia coli.

A minor species of isoleucine tRNA (tRNA(minor Ile)) specific to the codon AUA has been isolated from Escherichia coli B and a modified nucleoside N+ has been found in the first position of the anticodon (Harada, F., and Nishimura, S. (1974) Biochemistry 13, 300-307). In the present study, tRNA(minor Ile)) was purified from E. coli A19, and nucleoside N+ was prepared, by high-performance liquid chromatography, in an amount (0.6) A260 units) sufficient for the determination of chemical structures. By 400 MHz 1H NMR analysis, nucleoside N+ was found to have a pyrimidine moiety and a lysine moiety, the epsilon amino group of which was involved in the linkage between these two moieties. From the NMR analysis together with mass spectrometry, the structure of nucleoside N+ was determined as 4-amino-2-(N6-lysino)-1-(beta-D-ribofuranosyl)pyrimidinium ("lysidine"), which was confirmed by chemical synthesis. Lysidine is a novel type of modified cytidine with a lysine moiety and has one positive charge. Probably because of such a unique structure, lysidine in the first position of anticodon recognizes adenosine but not guanosine in the third position of codon.

Anticodon↗

Synthesis of decadeoxyribonucleotides containing 5-modified uracils and their interactions with restriction endonucleases Bgl II, Sau 3AI and Mbo I (nucleosides and nucleotides 82).

Decadeoxyribonucleotides containing uracil, 5-bromouracil, 5-cyanouracil and 5-ethyluracil in recognition sequences of restriction endonucleases Bgl II, Sau 3AI, Mbo I were synthesized. Decanucleotides containing 5-bromouracil in place of thymine had essentially the same susceptibility to all the restriction endonucleases. Uracil-containing decanucleotides were however very resistant to attack. Decanucleotides containing 5-cyanouracil in the recognition sequence were strongly resistant to hydrolysis by Sau 3AI, but were hydrolysed by Bgl II and Mbo I as well as the parent decanucleotide. Decanucleotides containing 5-ethyluracil were strongly resistant to hydrolysis by Sau 3AI, but were partially resistant to hydrolysis by Bgl II and Mbo I.

Bacterial Proteins↗

Different sensitivity to phorbol esters and pertussis toxin of bombesin- and platelet-derived growth factor-induced, phospholipase C-mediated hydrolysis of phosphoinositides in NIH/3T3 cells.

Incubation of the serum-deprived cultures of NIH/3T3 cells with bombesin or platelet-derived growth factor (PDGF) induced the phospholipase C-mediated hydrolysis of phosphoinositides. Protein kinase C-activating 12-O-tetradecanoylphorbol 13-acetate (TPA) and pertussis toxin inhibited the bombesin-induced phospholipase C reactions. AlF4-, a direct activator of GTP-binding proteins (G proteins), also induced the phospholipase C reactions and TPA inhibited the AlF4- -induced reactions. These results suggest that a pertussis toxin-sensitive G protein is involved in the coupling of the bombesin receptor to the phospholipase C and that the coupling of the G protein to the phospholipase C is inhibited by protein kinase C. In contrast, neither TPA nor pertussis toxin inhibited the PDGF-induced phospholipase C reactions, indicating that a pertussis toxin-sensitive G protein is not involved in the coupling of the PDGF receptor to the phospholipase C and that this coupling is insensitive to protein kinase C. These results suggest that the regulatory mechanism of the PDGF receptor for the phospholipase C activation is different from that of the bombesin receptor.

Adenosine Diphosphate Ribose↗

Prognostic value of histologic and clinical factors in 56 patients with gastrointestinal lymphomas.

To investigate the prognostic value of histologic and clinical factors in lymphomas of the gastrointestinal (GI) tract, the clinicopathologic findings in 56 Japanese patients with GI lymphomas were reviewed. They included 37 patients with gastric and 19 with intestinal lymphomas. The male to female ratio was 2.7:1 in gastric and 11:1 in small intestinal lymphomas. Histologically, all but one of intestinal lymphomas were high-grade lymphomas. Gastric lymphomas comprised 47% of low-grade and 53% of high-grade tumors. Significant factors for favorable prognosis identified by Cox's multivariate analysis were female sex, the presence of reactive lymphoid hyperplasia (RLH) in the primary site, early stage of disease, gastric lymphomas, and low-grade histologic type. The important role of chronic lymphocytic infiltration for development of gastric lymphoma was suggested by the high incidence of RLH and the intermediate lymphocytic type of lymphoma.

Adolescent↗

Early and delayed single photon emission CT in various cerebral diseases using N-isopropyl-p-(123I)iodoamphetamine.

Early and delayed single photon emission computed tomography (SPECT) using N-isopropyl-p-(123I)iodoamphetamine (IMP) was performed on 28 subjects (2 normal, 12 with cerebrovascular diseases and 14 with brain tumors) to evaluate the reversibility of the cerebral abnormality and cerebral viability. The results were compared with X-ray CT, 99mTc brain scintigraphy and rCBF by 133Xe inhalation method. Three types of IMP kinetics were observed. Initial hypoactivity that changed over 4 to 6 hours approaching a normal pattern suggests a hypofunctional parenchyma without significant tissue damage: long-lasting abnormalities on IMP SPECT indicates cellular damage.

Adolescent↗

Comparison of angiography and computed tomography using new morphologic criteria in staging of renal cell carcinoma.

The staging of tumor extension, and regional lymph node and venous involvement by angiography and computed tomography (CT) using new morphologic criteria were compared with the surgical and histopathologic stage in 59 patients (60 cases) with renal cell carcinoma. A high degree of accuracy in staging of both angiography and CT was demonstrated. However, CT was more accurate and sensitive than angiography in the evaluation of tumor extension and regional lymph node involvement, and equally accurate in that of venous involvement. We emphasize that new morphologic criteria of angiography and CT are clinically useful, and CT is the primary approach for the staging of renal cell carcinoma.

Angiography↗

Reorganization of cerebellar cell suspension transplanted into the weaver mutant cerebellum and immunohistochemical detection of synaptic formation.

Dissociated cells prepared from the cerebellar primordia of normal 15-day mouse embryos were grafted into the cerebellum of 1-month-old weaver mutant mice which are characterized by degeneration of cerebellar granule cells during the early postnatal period. The growth of the grafted cells was investigated at 1 month after the operation. Implanted cells were highly developed to form a large mass of tissue in the host cerebellar folia. Histological examination revealed that a trilaminar cortical structure was partially developed in certain areas of the grafted tissue. The implanted granule-like cells were labeled with [3H]thymidine which was injected into the host, suggesting that the granule-like cells actively proliferate in the host cerebellum after the transplantation. In this area, strong immunoreactivity with synapsin I was detected indicating that the dissociated granule cells of the cerebellar primordia are able to develop a synaptic organization in the weaver mouse cerebellum.

Animals↗

Biodistribution of N-isopropyl-p-iodoamphetamine in mice.

Biodistribution of N-isopropyl-p-iodoamphetamine (IMP) was evaluated in mice. After synthesis of IMP and exchange labeling with radioactive iodine, IMP was injected intravenously in male ddY mice. Activity in the brain reached 8.0 (%dose/g), at 10 min after injection and it was almost constant till 120 min. Activities in the lung and heart were high just after injection, decreased rapidly and was almost constant from 30 to 120 min. Activity in the liver increased slowly compared with other organs, and reached peak level at 60 min. In autoradiography, almost the same activity in the spinal cord as the brain was observed. Uptake and excretion of IMP were shown in kidneys and stomach, which may be the main route of the excretion of IMP and their metabolites. We concluded IMP showed good uptake in the central nervous system.

Amphetamines↗

A pyrimidine-based "flexible" bisubstrate analogue inhibitor of human thymidylate synthase.

The synthesis and characterization of two "flexible" bisubstrate analogues of the intermediate in the thymidylate synthase reaction are reported. Steric constraints are minimized and diasteromeric mixtures avoided by using a pyrimidine-based analogue as the folate portion of the inhibitor while retaining all known important binding sites. A preliminary assessment of certain conformational parameters by NMR is presented. The compounds are shown to be potent competitive inhibitors with respect to dUMP or 5,10-CH2-H4PteGlu but gave mixed kinetics with respect to 5,10-CH2-H4PteGlu5 for human thymidylate synthase.

Binding Sites↗

Structures of sugar chains of a p-nitrophenyl acetate-hydrolyzing esterase from the microsomes of rat liver.

The structures of sugar chains of a p-nitrophenyl acetate-hydrolyzing esterase from the microsomes of rat liver were established. The enzyme contained mannose and glucosamine as sugar components. Asparagine-linked sugar chains of the esterase were liberated by hydrazinolysis. After N-acetylation of the hydrazinolysate, the reducing ends of the sugar chains were coupled with 2-aminopyridine. Fluorescent pyridylamino (PA-) derivatives of sugar chains thus obtained were purified by gel filtration and reversed-phase HPLC. Eleven PA-sugar chains were obtained. The structures of the PA-sugar chains were first identified by HPLC using two series of separation systems by which 11 PA-oligomannose-type sugar chains with known structures could be separated. Further elucidation of the structures of each PA-sugar chain was performed by exoglycosidase digestions and partial acetolysis. The structures of two of the PA-sugar chains were further confirmed by 500 mHz 1H-NMR spectroscopy.

Animals↗