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T Usui

Publications and source records attributed to T Usui.

At least 181 records · Page 10Linked to original sources
PubMed1997

Structural organization of the human prostaglandin EP3 receptor subtype gene (PTGER3).

Prostaglandin EP3 receptor subtype is a seven-membrane-spanning protein with multiple C-terminal tails generated by alternative mRNA splicing. We report here the structural organization of the human EP3 gene (PTGER3). The human EP3 gene spanned more than 80 kb and was composed of 10 exons separated by nine introns. Exon 1 and the 5' 180-bp portion of exon 2 (exon 2a) encoded the seven transmembrane domains and 10 amino acid residues of the cytoplasmic tail, which are common to all EP3 isoforms. The 3' 3461-bp portion of exon 2 (exon 2b) or combinations of exons 3-10 encoded the EP3 isoform-specific C termini and formed their 3'-untranslated regions by multiple fashions of alternative mRNA splicing. Exons 2b, 4, 6, and 10 contained polyadenylation sites. The EP3 gene formed nine distinct mRNAs encoding eight EP3 isoforms, two of which were novel ones tentatively designated EP3-V and EP3-VI. The transcription initiation sites of the human EP3 gene were mapped 227 to approximately 231 bp upstream of the ATG start codon. The 360-bp 5'-flanking region contained a TATA box-like sequence, a GC box, and several cis-acting regulatory elements. The present study provides insight into the molecular mechanisms underlying the prostanoid receptor family.

Alternative Splicing↗
PubMed1997

Pharmacokinetic properties of YM17E, an inhibitor of acyl coenzyme A: cholesterol acyl transferase, and serum cholesterol levels in healthy volunteers.

We conducted a single and repeat oral dose study of YM17E, a novel inhibitor of acyl coenzyme A (CoA): cholesterol acyltransferase, in healthy male volunteers to evaluate the pharmacokinetic profile, tolerability and effect of the drug on serum cholesterol. In the single administration study, YM17E was administered after a meal to two groups of subjects (each containing six subjects taking the drug and three taking placebo) receiving 3, 60 and 300 mg or 15, 60 and 450 mg YM17E, respectively. Plasma concentrations of unchanged drug following single oral administration at 3-300 mg after a meal increased with increasing dose. In contrast, plasma concentrations after administration of 450 mg were almost the same as after 300 mg. Unchanged YM17E was not detected in urine after single administration, suggesting that it was excreted via the bile or urine after metabolism. Five active metabolites (M1, M2-a, M2-b, M3 and M4) were observed in plasma at concentrations comparable to those of unchanged YM17E. Their plasma concentrations increased in a slightly greater than dose-dependent manner from 3 to 300 mg. The effect of food was studied in an open crossover design with a 1-week washout period. Twelve subjects received 150 mg YM17E in both the fasted and post-prandial states. The AUC and Cmax after fasting were closely similar to those after a meal, showing that bioavailability was not affected by food intake. In the repeated oral dose study, the subjects received test drug at 150 mg or 300 mg (n = 6 each) or placebo (n = 3) twice a day (after breakfast and after dinner) for 7 days. On days 1 and 7, the subjects received YM17E once a day (after breakfast) for evaluation of pharmacokinetic properties. After repeated oral administration of 150 mg b.d., plasma concentrations reached steady state by day 5 (mean Cmin 48.6 ng.ml-1). After repeated administration of 300 mg b.d., plasma concentrations prior to each daily morning dose increased up to the 5th day (mean Cmin 166.6 ng.ml-1) and then tended to decrease until the 7th day. No significant signs, symptoms or changes in serum cholesterol levels were observed during the single and repeated oral dose studies at 150 mg b.d. Although statistical analysis was not conducted because of the small number of subjects, all subjects receiving repeated oral administration of 300 mg twice daily showed a 25% decrease in serum cholesterol level on day 7, but also the simultaneous occurrence of diarrhoea.

Administration, Oral↗
PubMed1997

A lectin from mycelia of the fungus Ganoderma lucidum.

A lectin (GLL-M) was isolated from mycelia of Ganoderma lucidum using affinity chromatography on BSM-Toyopearl. GLL-M is a monomer in its native form with a M(r) of 18,000. Another lectin was also purified from fruiting bodies of the same fungus. The two lectins were partially compared with each other.

Amino Acids↗
PubMed1997

Axon patterning requires DN-cadherin, a novel neuronal adhesion receptor, in the Drosophila embryonic CNS.

We identified DN-cadherin, a novel Drosophila cadherin that is expressed in axons and in the mesoderm. Although DN-cadherin has diverged from vertebrate classic cadherins in terms of its extracellular structure, it still can form a complex with catenins and induce cell aggregation, as do the vertebrate molecules. Loss-of-function mutations of the gene resulted in either embryonic lethality or uncoordinated locomotion of adults. In the central nervous system of null mutant embryos, subsets of ipsilateral axons displayed a variety of aberrant trajectories including failure of position shifts, defective bundling, and errors in directional migration of growth cones. These results suggest that processes of axon patterning critically depend on DN-cadherin-mediated axon-axon interactions.

Animals↗
PubMed1997

Pharmacokinetics of recombinant human interleukin-11 (rhIL-11) in healthy male subjects.

AIMS: To study the pharmacokinetics of recombinant human interleukin-11 (rhIL-11) in healthy male volunteers following subcutaneous (s.c.) and intravenous (i.v.) administration. METHODS: RhIL-11 was infused intravenously at 10-50 micrograms kg-1 for 1 or 3 h, or administered subcutaneously at 3-50 micrograms kg-1 to volunteers. RhIL-11 was also administered at 3 micrograms kg-1 s.c. once daily for 7 days. Plasma and urinary concentrations were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: RhIL-11 showed linear pharmacokinetics after both intravenous infusion and s.c. administration. Comparison of t1/2 and MRT values after i.v. administration with those after s.c. administration indicated that rhIL-11 pharmacokinetics after s.c. administration were absorption rate-limited. Bioavailability after s.c. administration was about 65%. Since RhIL-11 was not detected in urine after a single 50 micrograms kg-1 s.c. dose, rhIL-11 was considered to be eliminated by metabolism. There was no significant change in the pharmacokinetic profile of rhIL-11 following repeated s.c. administration. CONCLUSIONS: RhIL-11 demonstrated linear pharmacokinetics at these dose ranges after single and repeated s.c. administration or constant-rate i.v. infusion in healthy volunteers.

Adolescent↗
PubMed1997

Drug disposition of incadronate, a new bisphosphonate, in rats with bone metastases.

1. Drug disposition of incadronate in the nude rat with bone metastases induced by A375 human melanoma cells was studied after intravenous administration. 2. The pharmacokinetics of incadronate (plasma concentration, urinary excretion and bone uptake) in rat with bone metastases was not markedly different from that in the control rat. This compound, however, was selectively taken up in the bone region around metastatic tumour nests. 3. Drug concentrations in the bone region around tumour nests were 3-10 micrograms/g, these levels being higher than the IC50 (0.35 microgram/ml) for the inhibitory effect of this drug on osteoclasts in vitro. 4. In contrast, concentrations in the tumour nest itself was < 0.7 microgram/g, being markedly lower than the IC50 (35 micrograms/ml) for the inhibitory effect on the proliferation of tumour cells in vitro. 5. These results strongly suggest that pharmacological action of incadronate in mouse with bone metastases (inhibitory effect on the growth of metastatic tumour in bone) is caused not by the direct action on the tumour cells but by the distribution of the drug in the perifocal bone region followed by inhibition of the activity of osteoclasts, resulting in inhibition of the osteolytic process, which is necessary for the progress of metastatic tumour.

Animals↗
PubMed1997

Inhalation of interleukin-2 combined with subcutaneous administration of interferon for the treatment of pulmonary metastases from renal cell carcinoma.

BACKGROUND: Interleukin-2 is the most promising antitumor agent for advanced renal cell carcinoma, but systemic immunotherapy with interleukin-2 might be limited because of inadequate efficacy and severe adverse effects. In this study, we treated 7 patients with lung metastases from renal cell carcinoma with topical application of interleukin-2 by inhalation. METHODS: Patients received 100,000 IU of interleukin-2 by inhalation 4 times a day and 9,000,000 IU of interferon-alfa-2a subcutaneously for 5 consecutive days per week. They also received, by oral administration, 800 mg of cimetidine and 50 mg of indomethacin per day. After informed consent was obtained, the treatment started and the absence of any intolerable adverse effects was confirmed in a hospital. Then the treatment continued in an outpatient clinic for at least 3 months. RESULTS: Of 6 assessable patients, 5 responded to this treatment; 2 patients developed a partial response (33%) and 3 remained stable (67%). Disease progressed in the remaining patient. Therapy was discontinued in 1 patient because of his poor general condition. No severe adverse effects were observed, but pulmonary fibrosis probably associated with this treatment occurred in 1 patient. CONCLUSION: Although more cases and further evaluation are necessary to assess the significance and the safety of the inhalation of interleukin-2, this treatment is anticipated to be an option for selected patients with lung metastases from renal cell carcinoma.

Administration, Inhalation↗
PubMed1997

Preparation of oligosaccharide units library and its utilization.

There is high current interest in developing synthetic routes to oligosaccharides involved in glycoconjugates. Significant attention has been focused on the application of glycosidase-catalyzed transglycosylation for practical synthesis of oligosaccharides. The enzymatic synthesis has become more practical by the use of several glycosidases available in sufficient quantities. This review describes convenient syntheses of di- and trisaccharide units, which are related to molecular recognition, by using regioselective transgalactosylation, trans-N-acetylglucosaminylation, transfucosylation, and transmannosylation. The regioselectivity could be controlled to some extent by using the following techniques: (1) varying enzymes, (2) organic co-solvent system, (3) the configuration of the existing glycosidic linkage of the acceptor and (4) inclusion complex of acceptor glycoside with cyclodextrin. Furthermore, glycopolymers carrying a series of disaccharides containing beta-D-galactosyl residues were synthesized and used as a model in oligosaccharide-lectin interaction analysis. These water-soluble glycopolymers were shown to be useful as probes of carbohydrate recognition.

Acetylglucosamine↗
PubMed1997

Galactosyl transfer onto p-nitrophenyl beta-D-glucoside using beta-D-galactosidase from Bacillus circulans.

beta-D-Gal-(1-->4)-beta-D-Glc-OC6H4NO2-p and its isomers (beta-D-Gal-(1-->3)-beta-D-Glc-OC6H4NO2-p and beta-D-Gal-(1-->6)-beta-D-Glc-OC6H4NO2-p) were synthesized from lactose and beta-D-Glc-OC6H4NO2-p, using transglycosylation by the beta-D-galactosidase from Bacillus circulans. This reaction was efficient enough for us to do a one-pot preparation of galactosyl-glucoside from lactose. The order of the production of the transfer products was (1-->4) > > (1-->3) > (1-->6) in the initial stage of the reaction, and the same relationship was observed for the hydrolytic rate toward the three galactosyl-glucosides. The production of (1-->4)- and (1-->3)-linkages greatly decreased during the subsequent reaction and much more of the (1-->6)- than of the (1-->4)- and (1-->3)-transfer products was found in the later stage of the reaction.

Bacillus↗
PubMed1997

[Localization and expression of matrix metalloproteinase-7 in human prostate].

BACKGROUND: Matrix metalloproteinases-7 (MMP-7), one of an extracellular matrixdegrading metalloproteinase, play an important role tumor invasion and metastasis. We investigated localization, biochemical characterization and mRNA expression of MMP-7 in prostate tissues. METHODS: Immunohistochemical method, SDS-polyacrylamide gel electrophoresis and northern blot analysis were performed using tissues of prostatic cancer, BPH and normal prostate. RESULTS: A latent proenzyme with Mr28,000 of MMP-7 was detected in the ductal epithelial cells of BPH and in the cytoplasm of cancer cell of the prostate. The ratio of mRNA expression in MMP-7/beta-actin was significantly higher in the tissue of the invasive prostatic cancer than those of normal prostate and BPH in northern blot analysis. CONCLUSIONS: These results suggest that MMP-7 may participate in the function of exocrine gland of normal prostate by preventing glandular obstruction and may play a role in invasion and metastasis of prostatic cancer.

Extracellular Matrix↗
PubMed1997

Pharmacokinetics of incadronate, a new bisphosphonate, in healthy volunteers and patients with malignancy-associated hypercalcemia.

We investigated the pharmacokinetics of incadronate, a new bisphosphonate, after a 2-hour intravenous infusion to healthy volunteers and patients with malignancy-associated hypercalcemia. Following administration at 0.025-1.6 mg to healthy volunteers, peak plasma concentration of incadronate increased in a dose-proportional manner. Plasma concentration thereafter declined biexponentially with a half-life of 0.26-0.40 h (t1/2 alpha) and 1.58-1.98 h (t1/2 beta). AUC increased dose-proportionally, whereas distribution volume (Vdss), total body clearance (CLt), renal clearance (CLr) and nonrenal clearance (CLnr), corresponding to bone uptake clearance, changed little among doses, indicating the linear pharmacokinetics of the drug after intravenous administration. Within 24 h, 55.1-69.5% of the dose was excreted into urine as the unchanged drug, most in the first 6 h. CLr and CLnr accounted for about 60% and 40% of the CLt, respectively, suggesting that the pharmacokinetics of incadronate are affected by changes in these clearances. In patients, plasma concentration at 2 h increased dose-proportionally in the range of 2.5-10.0 mg. Urinary excretion of YM175 up to 24 h after dosing was as low as 10.5% of the dose, being 1/6 of those in volunteers. A positive correlation (r > 0.89) was observed between creatinine clearance and urinary incadronate excretion in all volunteers and patients, indicating that the reduction of urinary excretion in patients is due to the decrease in renal function accompanying hypercalcemia. Based on comparison of the dose-normalized plasma concentration, the plasma level at 2 h in patients was comparable with that in volunteers, whereas the level at 8 h was 3 times higher in patients, suggesting that elimination from plasma in patients is delayed due to decreased renal function. Nevertheless, the plasma concentration profile in patients was lower than that predicted from the decrease in CLr. This finding suggests that the increase in plasma concentration with decreasing renal excretion in hypercalcemic patients was compensated for by enhanced bone uptake of the drug.

Adult↗
PubMed1996

Purification and characterization of a lectin from the toxic mushroom Amanita pantherina.

A lectin (APL) was isolated from the mushroom Amantia pantherina by means of hydrophobic chromatography on Butyl-Toyopearl, affinity chromatography on bovine submaxillary mucin (BSM)-Toyopearl and gel filtration on Superose 12 HR10/30 using a FPLC system. This lectin is composed of two identical subunits of 22 kDa and the molecular mass of the intact lectin was estimated to be 43 kDa by gel filtration. In hemagglutination inhibition assays, it exhibits sugar-binding specificities towards GlcNAc beta 1-->4Man beta-pNP, Gal beta 1-->4GlcNAc beta 1-->4GlcNAc, and Gal beta 1-->4GlcNAc beta 1-->4GlcNAc beta 1-->4GlcNAc among mono- and oligosaccharides tested. Among glycoproteins tested, BSM and asialo-BSM were the strongest inhibitors.

Amanita↗
PubMed1996

Gene expression of the human prostaglandin E receptor EP4 subtype: differential regulation in monocytoid and lymphoid lineage cells by phorbol ester.

We isolated a cDNA clone encoding the human prostaglandin (PG) E receptor EP4 subtype and examined the gene expression in human blood cells. Northern blot analysis revealed that the EP4 gene is expressed at a high level in peripheral blood mononuclear cells, and at lower levels in cultured human blood cell lines, THP-1 and U937 (monocytoid cell lines), MOLT-4 and Jurkat (T-cell lines), and Raji (B-cell line). To examine regulation of the EP4 gene expression in the immune system, we studied the effects of phorbol 12-myristate 13-acetate (PMA) on these cell lines. Gene expression was upregulated in THP-1, U937, and Raji cells by PMA, and was downregulated in MOLT-4 and Jurkat cells. In THP-1 cells the effects of PMA were further analyzed, and the upregulation of the EP4 gene was shown to be followed by an increase in PGE2 binding sites and in PGE2-induced cAMP accumulation. In the striking contrast, other PGE receptor subtypes (EP1, EP2 and EP3) and other prostanoid receptors (IP and DP) were shown not to be upregulated by PMA. Therefore, this is the first demonstration of a highly specific upregulation of the EP4 subtype in THP-1 cells treated with PMA, suggesting the importance of the EP4 subtype in the immune system. In the present study we also clarified that EP4 gene expression is regulated differently among human monocytoid and lymphoid lineage cells, thus leading to the better understanding of the regulatory mechanisms for the human EP4 gene expression in the immune system.

Burkitt Lymphoma↗
PubMed1996

Effect of cysteamine on gastric nerve fibers containing gastrin-releasing peptide in the rat.

In rats, changes in gastric nerve fibers containing gastrin-releasing peptide (GRP) in cysteamine-induced duodenal ulcer were investigated in relation to the dynamics of gastrin-producing cells (G-cells). Marked increases in gastric acid secretion and serum gastrin level were observed from 2 h after the administration of cysteamine. The number of G-cells was significantly decreased from 2 h after the injection of cysteamine. Two and 4 h after the administration of cysteamine, the G-cells showed ultrastructural changes characterized by a markedly decreased number of secretory granules. Circulating GRP levels were significantly elevated from 2 h after the administration of cysteamine. In the control group given vehicle only, nerve fibers showing immunoreaction for GRP formed a fine network in the gastric wall and were densely distributed in the oxyntic mucosa, located close to capillaries and demonstrated varicosities that contained either small clear vesicles or GRP-immunopositive vesicles with large cores. Eight h after the administration of cysteamine, there was depleted GRP immunoreactivity, evidenced by a markedly decreased number of vesicles, with large electron-dense cores, in the oxyntic mucosa. These findings suggest that, in cysteamine-induced duodenal ulcer, alterations in gastric nerve fibers containing GRP may be related to hypergastrinemia.

Animals↗