19 results on '"Kozutsumi D"'
Search Results
2. An Improved Method for Acetaldehyde Determination in Blood by High-Performance Liquid Chromatography and Solid-Phase Extraction
- Author
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Kozutsumi, D., primary, Arita, M., additional, Kawashima, A., additional, Adachi, M., additional, and Takami, M., additional
- Published
- 2002
- Full Text
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3. A new assay for lipiodol in a tumor using a combination of m-chloroperbenzoic acid-mediated oxidation and the iodo-starch reaction
- Author
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Kozutsumi, D., Ohshiba, Y., Sugimoto, T., Tsuboi, H., Kawashima, A., Kochiya, M., Adachi, M., and Takami, M.
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- 2000
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4. Clonal dominance of human autologous cytotoxic T lymphocytes against gastric carcinoma: molecular stability of the CDR3 structure of the TCR alphabeta gene.
- Author
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Ikeda, H, Sato, N, Matsuura, A, Sasaki, A, Takahashi, S, Kozutsumi, D, Kobata, T, Okumura, K, Wada, Y, Hirata, K, and Kikuchi, K
- Abstract
In our previous study, RT-PCR suggested that cytotoxic T lymphocyte (CTL) clones may specifically recognize human autologous gastric signet ring cell tumor (HST2) by using TCR products of Valpha7 and Vbeta20 subfamilies. In this report, we first determined the TCR nucleotide sequences of one such CTL from patient's peripheral blood lymphocytes (PBL), the PBL were newly stimulated with a mixed lymphocyte-autologus tumor cell (HST2) culture (MLTC) and cytotoxic T cell lines, such as HPBL3x, were obtained. RT-PCR and the nucleotide sequence data indicated that HPBL3x also showed TCR Valpha7 and Vbeta transcripts, and that HPBL3x TCR was composed of the exact same CDR3 gene structures as those of the TcHLT2 clone. T cells with same TCR structures were also detected in patient's non-treated peripheral blood, although they were infrequent. These data indicated that functional cytotoxic T cells with these distinct CDR3 equivalent structures were the dominant effector cells against HST2 autologous tumor cells. Moreover, the highly dominant and reproducible clonal expansion of T cells bearing heterodimeric TCR with identical variable, N diversity and constant region structures suggest that the molecular nature of governing antigenic peptide to TcHDT2 may be stable and perhaps immunologically dominant in the interaction between CTL and HST2 autologous tumor cells.
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- 1996
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5. Effects of aliphatic aldehydes on the growth and patulin production of Penicillium expansum in apple juice.
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Taguchi T, Kozutsumi D, Nakamura R, Sato Y, Ishihara A, and Nakajima H
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- Acrolein pharmacology, Acyltransferases genetics, Acyltransferases metabolism, Fermentation drug effects, Fruit chemistry, Fungal Proteins genetics, Fungal Proteins metabolism, Gene Expression drug effects, Ligases genetics, Ligases metabolism, Multienzyme Complexes genetics, Multienzyme Complexes metabolism, Mycelium growth & development, Mycelium metabolism, Oxidoreductases genetics, Oxidoreductases metabolism, Patulin agonists, Patulin antagonists & inhibitors, Penicillium growth & development, Penicillium metabolism, Spores, Fungal growth & development, Spores, Fungal metabolism, Transcription, Genetic drug effects, Aldehydes pharmacology, Beverages, Malus chemistry, Mycelium drug effects, Patulin biosynthesis, Penicillium drug effects, Spores, Fungal drug effects
- Abstract
The effects of 16 aliphatic aldehydes with 3-10 carbons on the growth and patulin production of Penicillium expansum were examined. When P. expansum spores were inoculated into apple juice broth, some alkenals, including 2-propenal, (E)-2-butenal, (E)-2-pentenal, and (E)-2-hexenal, inhibited fungal growth and patulin production. Their minimal inhibitory concentrations were 5, 50, 80, and 80 µg/mL respectively. Vital staining indicated that these alkenals killed mycelia within 4 h. Treatment of the spores with these aldehydes also resulted in rapid loss of germination ability, within 0.5-2 d. On the other hand, aliphatic aldehydes with 8-10 carbons significantly enhanced patulin production without affecting fungal growth: 300 µg/mL of octanal and 100 µg/mL of (E)-2-octenal increased the patulin concentrations in the culture broth by as much as 8.6- and 7.8-fold as compared to that of the control culture respectively. The expression of the genes involved in patulin biosynthesis in P. expansum was investigated in mycelia cultured in apple juice broth containing 300 µg/mL of octanal for 3.5, 5, and 7 d. Transcription of the msas gene, encoding 6-methylsalicylic acid synthase, which catalyzed the first step in the patulin biosynthetic pathway was remarkably high in the 3.5-d and 5-d-old cultures as compared with the control. However, octanal did not any increase the transcription of the msas in the 7-d-old culture or that of the other two genes, IDH and the peab1, in culture. Thus the enhanced patulin accumulation with supplementation with these aldehydes is attributable to the increased amount of the msas transcript.
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- 2013
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6. [Multiresidue method for pesticides and veterinary drugs in bovine milk using GC/MS and LC/MS/MS].
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Saito M, Kozutsumi D, Kawasaki M, Kanbashi M, Nakamura R, Sato Y, and Endo M
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- Animals, Cattle, Female, Gas Chromatography-Mass Spectrometry, Milk chemistry, Pesticide Residues analysis, Tandem Mass Spectrometry, Veterinary Drugs analysis
- Abstract
A simple, sensitive and selective method with gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been developed to detect 342 pesticides and veterinary drugs contaminating bovine milk at the maximum residue limits (MRLs) defined in the "positive list system". Sample preparation was performed by extracting the analytes with acetonitrile, followed by salting-out with sodium chloride. For some pesticides, the extract was further cleaned up by n-hexane partitioning and PSA cartridge column chromatography. GC/MS-EI or -NCI was used to determine pesticide residues, while LC/MS/MS-ESI was applicable to the determination of pesticide and veterinary drug residues. The variation of the recoveries of these drugs at MRL was relatively wide; however the relative standard deviations of the recovery of each drug were within 28%, suggesting that the present method is good enough for use as a screening test for contaminants at the MRLs. These results show that this method is useful for multiresidue analysis of numerous pesticides and veterinary drugs in bovine milk.
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- 2008
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7. A new murine model of allergic rhinitis by repeated intranasal Cry j 1 challenge.
- Author
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Tsunematsu M, Yamaji T, Kozutsumi D, Murakami R, Nagai H, and Kino K
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- Administration, Intranasal, Allergens blood, Allergens immunology, Animals, Antibodies blood, Antigens, Plant, Enzyme-Linked Immunosorbent Assay, Female, Plant Proteins blood, Plant Proteins immunology, Sneezing, Allergens administration & dosage, Disease Models, Animal, Mice, Plant Proteins administration & dosage, Rhinitis, Allergic, Seasonal immunology
- Abstract
To evaluate the long-lasting effects of new therapeutic approaches to allergies, we established a new model of allergic rhinitis by repeated challenges with intranasal Cry j 1, a common Japanese cedar (Cryptomeria japonica) pollen allergen, in B10.S mice. We sensitized B10.S mice subcutaneously with Cry j 1/alum three times at 1-week intervals. Five weeks after the final sensitization, we challenged the mice by instilling Cry j 1 intranasally for 5 consecutive days starting 1 day after intranasal histamine pretreatment (challenge-1). We challenged the mice by instilling histamine and Cry j 1 intranasally again 12 weeks later (challenge-2). There were significantly more sneezes after challenge-2 than challenge-1. Cry j 1-specific IgE levels in serum were significantly increased in both challenge-1 and 2 after continuous nasal antigen challenge. Serum levels of anti-Cry j 1 IgE in challenge-2 was 2.3 times higher than after challenge-1. Thus, we have established a new model of seasonal allergic rhinitis in B10.S mice by repeated intranasal antigen challenge, and this model may help elucidate mechanisms of allergic rhinitis and the development of new drugs.
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- 2008
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8. Effect of Cry-consensus peptide, a novel recombinant peptide for immunotherapy of Japanese cedar pollinosis, on an experimental allergic rhinitis model in B10.S mice.
- Author
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Tsunematsu M, Yamaji T, Kozutsumi D, Murakami R, Kimura S, and Kino K
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- Allergens genetics, Allergens immunology, Amino Acid Sequence, Animals, Disease Models, Animal, Epitopes, T-Lymphocyte genetics, Epitopes, T-Lymphocyte immunology, Female, Humans, Japan, Mice, Mice, Inbred C57BL, Molecular Sequence Data, Recombinant Proteins genetics, Recombinant Proteins immunology, Rhinitis, Allergic, Seasonal pathology, Tetraspanins, Allergens therapeutic use, Cryptomeria immunology, Desensitization, Immunologic, Membrane Proteins biosynthesis, Membrane Proteins genetics, Pollen immunology, Recombinant Proteins therapeutic use, Rhinitis, Allergic, Seasonal immunology, Rhinitis, Allergic, Seasonal therapy
- Abstract
Background: We are developing an immunotherapeutic peptide, Cry-consensus peptide, for Japanese cedar pollinosis. Cry-consensus peptide is a recombinant polypeptide containing six major human T-cell epitopes derived from both Cry j 1 and Cry j 2, two major allergens of Japanese cedar pollen. We examined the effect of Cry-consensus peptide on an allergic rhinitis model in B10.S mice, which have one common T-cell epitope in the Cry-consensus peptide., Methods: B10.S mice were sensitized with Cry j 1/alum, then the Cry-consensus peptide was administered subcutaneously once a week for 5 weeks from the last sensitization. Histamine was dropped in both nostrils (10 microL per nostril) of each mouse on the day before continuous intranasal instillation of Cry j 1. Soon after the final challenge with Cry j 1, the mice were observed for 5 minutes for the resulting number of sneezes. In addition, serum levels of Cry j 1-specific IgE and IgG2a antibody, eosinophil infiltration in nasal tissue, and Cry j 1-specific cytokine production from splenocytes were evaluated., Results: Cry-consensus peptide markedly inhibited Cry j 1-induced sneezes, eosinophil infiltration, and eosinophil peroxidase (EPO) activity in nasal tissue. Cry-consensus peptide inhibited the production of anti-Cry j 1 IgE (Th2-mediated) and significantly enhanced anti-Cry j 1 IgG2a (Th1-mediated). In cytokine production from splenocytes, Cry-consensus peptide significantly decreased in IL-4/IFN-gamma and IL-5/IFN-gamma ratios., Conclusions: It was concluded that Cry-consensus peptide effectively controlled allergic responses, which results from shifting from a Th2-dominated to a Th1-dominated immune response.
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- 2007
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9. Biological assay using T cell response for Cry-consensus peptide designed for the peptide-based immunotherapy of Japanese cedar pollinosis.
- Author
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Kozutsumi D, Tsunematsu M, Yamaji T, and Kino K
- Subjects
- Adult, Amino Acid Sequence, Cell Proliferation, Cells, Cultured, Epitopes, T-Lymphocyte immunology, Humans, Immunoglobulin E blood, Leukocytes, Mononuclear immunology, Middle Aged, Pollen immunology, Protein Denaturation, Recombinant Proteins chemistry, Recombinant Proteins immunology, Rhinitis, Allergic, Seasonal immunology, Sensitivity and Specificity, Thymidine, Allergens immunology, Biological Assay methods, Cryptomeria immunology, Recombinant Proteins therapeutic use, Rhinitis, Allergic, Seasonal therapy
- Abstract
Introduction: Cry-consensus peptide is a linearly linked peptide of T-cell epitopes for the management of Japanese cedar (JC) pollinosis and is expected to become a new drug for immunotherapy. However, the mechanism of T-cell epitopes in allergic diseases is not well understood, and thus, a simple in vitro procedure for evaluation of its biological activity is desired., Methods: Peripheral blood mononuclear cells (PBMC) were isolated from 27 JC pollinosis patients and 10 healthy subjects, and cultured in vitro for 4 days in the presence of Cry-consensus peptide and (3)H-thymidine. The relationship between growth stimulation (stimulation index; SI) and antigen-specific IgE levels in serum was also investigated in JC pollinosis patients. Moreover, to confirm the importance of the primary sequence in Cry-consensus peptide, heat-treated Cry-consensus peptide and a mixture of the amino acids of which Cry-consensus peptide is composed, and their (3)H-thymidine uptake was compared with Cry-consensus peptide. Finally, whether Cry-consensus peptide stimulates PBMCs from healthy subjects was investigated., Results: The mean SI of JC patients showed a good correlation with Cry-consensus peptide concentration in the culture medium; however, the SI was independent of the anti-Cry j 1 IgE level. Heat-denatured Cry-consensus peptide retained a PBMC proliferation stimulatory effect comparable to the original Cry-consensus peptide, while the mixture of amino acids constituting Cry-consensus peptide did not stimulate PBMC proliferation. PBMCs from healthy subjects did not respond to Cry-consensus peptide at all., Discussion: These data indicate that the PBMC response of patients suffering from JC pollinosis to Cry-consensus peptide is specific for the sequence of T cell epitopes thereof and may be useful for the evaluation of the efficacy of Cry-consensus peptide in vivo.
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- 2007
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10. Establishment of an allergic rhinitis model in mice for the evaluation of nasal symptoms.
- Author
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Tsunematsu M, Yamaji T, Kozutsumi D, Murakami R, Kimura S, and Kino K
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- Animals, Anti-Allergic Agents pharmacology, Anti-Inflammatory Agents pharmacology, Antigens immunology, Cryptomeria, Dexamethasone pharmacology, Disease Models, Animal, Eosinophils enzymology, Eosinophils pathology, Female, Histamine pharmacology, Immunization, Immunoglobulin E immunology, Ketotifen pharmacology, Mice, Peroxidases metabolism, Pollen immunology, Rhinitis, Allergic, Seasonal immunology, Sneezing drug effects, Nasal Mucosa pathology, Rhinitis, Allergic, Seasonal pathology
- Abstract
The purpose of our study was to establish a new model of allergic rhinitis in mice, eliciting symptoms such as sneezing, infiltration of eosinophils into the nasal mucosa, and antigen-specific IgE production. One of the major human T-cell epitopes in Cry j 1, an allergen of Japanese cedar pollen, is also a major murine T-cell epitope in B10.S mice. Thus we tried to establish an allergic rhinitis model in B10.S mice with Cry j 1 as the antigen. We sensitized B10.S mice subcutaneously with Cry j 1/alum three times at intervals of 1 week. Five weeks after the final sensitization, we challenged the mice by instilling Cry j 1 intranasally from the day after intranasal histamine pretreatment. Soon after, we counted the number of sneezes. We then evaluated the infiltration of eosinophils into the nasal tissues and also measured the serum levels of antigen-specific IgE antibody. In addition, we confirmed the effects of ketotifen fumarate and dexamethasone hydrochloride on these animals. In Cry j 1-sensitized B10.S mice, sneezes, eosinophil peroxidase (EPO) activity in nasal tissues, and Cry j 1-specific IgE clearly increased after intranasal histamine pretreatment and 5 days of continuous intranasal Cry j 1 challenge. Both ketotifen and dexamethasone inhibited the increase in sneezing, and dexamethasone also inhibited EPO activity and Cry j 1-specific IgE. Thus we succeeded in establishing a new model of allergic rhinitis in Cry j 1-sensitized B10.S mice, which exhibited sneezing, eosinophil infiltration into the nasal mucosa, and Cry j 1-specific IgE production.
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- 2007
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11. Enzyme-linked immunosorbent assay of a linear, recombinant peptide designed for immunotherapy of Japanese cedar pollinosis.
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Kozutsumi D, Shimizu K, Morikubo K, Ohshiba Y, Yamaji T, and Kino K
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- Amino Acid Sequence, Antibodies, Monoclonal, Antigens, Plant, Enzyme-Linked Immunosorbent Assay, Epitopes, Humans, Molecular Sequence Data, Protein Folding, Recombinant Proteins immunology, Rhinitis, Allergic, Seasonal immunology, Allergens immunology, Cryptomeria immunology, Plant Proteins immunology, Recombinant Proteins analysis, Rhinitis, Allergic, Seasonal therapy
- Abstract
Introduction: Cry-consensus peptide, a recombinant T-cell epitope peptide for immunotherapy of Japanese cedar pollinosis, is a linear peptide that does not have disulfide bonds because no cysteine residue exists in the molecule. We examined whether a sandwich enzyme-linked immunosorbent assay (ELISA) could be performed for linear peptides such as Cry-consensus peptide., Methods: The 3-dimensional conformation of Cry-consensus peptide was examined by (1)H NMR analysis. Nineteen monoclonal antibodies (mAbs) that recognized various domains of Cry-consensus peptide were established to use in a sandwich ELISA. The relationship between the recognition sites of mAbs and the sensitivity of the ELISA was investigated to optimize the selection of the combination of the capture and the detection antibodies. ELISA inhibitors in serum and plasma were also studied to improve the stability and the sensitivity of determination., Results: (1)H NMR analysis of Cry-consensus peptide suggested that Cry-consensus peptide molecule had no portions with rigid conformation. The sensitivity of the ELISA showed a good correlation with the distance between the respective binding sites of the capture and the detection antibodies. Human serum albumin and alpha1-acid glycoprotein strongly inhibited the binding of the capture mAb to Cry-consensus peptide in a dose-dependent manner, and heparin also inhibited the binding in the concentration at which it is used as anticoagulant. Taken together, the findings indicated that an optimized method showed good linearity and minimal variation from 0 to 1000 ng/ml of Cry-consensus peptide., Discussion: These data indicate that this method is useful for monitoring Cry-consensus peptide concentrations in plasma or serum.
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- 2007
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12. Cry-consensus peptide, a novel peptide for immunotherapy of Japanese cedar pollinosis, induces Th1-predominant response in Cry j 1-sensitized B10.S mice.
- Author
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Kozutsumi D, Tsunematsu M, Yamaji T, Murakami R, Yokoyama M, and Kino K
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- Allergens administration & dosage, Animals, Antigens, Plant, Cells, Cultured, Cytokines biosynthesis, Enzyme-Linked Immunosorbent Assay, Humans, Mice, Peptides immunology, Plant Proteins administration & dosage, Rhinitis, Allergic, Seasonal immunology, Allergens adverse effects, Immunotherapy, Peptides therapeutic use, Plant Proteins adverse effects, Rhinitis, Allergic, Seasonal therapy, Th1 Cells immunology
- Abstract
Cry-consensus peptide (CCP) is a newly designed peptide for peptide-based immunotherapy of Japanese cedar pollinosis but its mechanism of efficacy is unknown. We investigated the effect of CCP on Cry j 1-specific Th1/Th2 response in a mice model. Subcutaneous injection of CCP decreased Cry j 1-specific IgE and IgG1 in blood slightly, but the IgG2a level was increased significantly in a dose dependent manner. Splenocytes from these mice were stimulated with Cry j 1 in vitro. This inhibited IL-4, IL-5 and IL-10 secretion significantly, but IFN-gamma secretion was increased. In vitro CCP stimulation of splenocytes from Cry j 1-sensitized mice induced more marked Th1-predominancy of cytokine production than native allergen stimulation. Taken together, these data suggest that one of the mechanisms of CCP is dependent on the modulation of the antigen-specific Th1/Th2 response.
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- 2006
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13. PS80 interferes with the antiallergic effect of Cry-consensus peptide, a novel recombinant peptide for immunotherapy of Japanese cedar pollinosis, at very low concentration through modulation of Th1/Th2 balance.
- Author
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Kozutsumi D, Tsunematsu M, Yamaji T, Murakami R, Yokoyama M, and Kino K
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- Allergens genetics, Allergens immunology, Amino Acid Sequence, Animals, Antigens, Plant, Cells, Cultured, Dendritic Cells immunology, Desensitization, Immunologic methods, Disease Models, Animal, Dose-Response Relationship, Immunologic, Endocytosis drug effects, Endocytosis immunology, Epitopes, T-Lymphocyte immunology, Immunologic Factors immunology, Interferon-gamma biosynthesis, Interleukin-5 biosynthesis, Mice, Mice, Inbred Strains, Molecular Sequence Data, Plant Proteins genetics, Plant Proteins immunology, Recombinant Proteins genetics, Recombinant Proteins immunology, Rhinitis, Allergic, Seasonal immunology, Spleen immunology, Th1 Cells immunology, Th2 Cells immunology, Allergens therapeutic use, Cryptomeria immunology, Plant Proteins therapeutic use, Polysorbates pharmacology, Recombinant Proteins therapeutic use, Rhinitis, Allergic, Seasonal therapy
- Abstract
Polysorbate 80 (PS80 or Tween-80) is often used as an additive to promote the rapid solubilization of pharmaceuticals in aqueous solutions. We investigated whether coinjection of a minimal amount of PS80 had a modulatory effect on the immunotherapeutic effects of Cry (Cryptomeria)-consensus peptide, a novel peptide developed for the therapeutic management of Japanese cedar pollinosis, using a Cry j 1-sensitized mouse model with experimental allergic rhinitis. Subcutaneous challenge with Cry-consensus peptide plus 50 microg/ml of PS80 did not affect the antigen-specific proliferation of splenocytes, but decreased the potency of Cry-consensus peptide to inhibit antigen-specific interleukin (IL)-5 production by the cells significantly in comparison with challenge with Cry-consensus peptide alone. However, there was no significant difference between the effect of Cry-consensus peptide administration on interferon (IFN)-gamma production in the presence and absence of PS80, indicating that PS80 interfered with the T helper 1 (Th1)-dominant T helper balance induced by Cry-consensus peptide challenge. Moreover, the increase in the level of antigen-specific immunoglobulin G2a (IgG2a) induced by Cry-consensus peptide challenge was inhibited slightly but unambiguously by PS80 coinjection. These in vitro experiments indicated that PS80 induces Th2-type differentiation of T helper cells through preferential inhibition of IFN-gamma expression relative to IL-5 expression in splenocytes in a concentration-dependent manner. In naïve mice, sensitization by Cry-consensus peptide with PS80 induced antigen-specific IL-5 production more potently than sensitization by Cry-consensus peptide alone, and when PS80 was added to bone marrow-derived dendritic cells, the endocytosis of fluorescence-labelled Cry-consensus peptide was dramatically inhibited in a concentration-dependent manner. Therefore, we conclude that PS80 has an immunomodulatory effect on the antigen-specific response resulting in a shift towards Th2 predominance with respect to the antigen recognition stage. Taken together, our findings suggest that PS80 might decrease the efficacy of Cry-consensus peptide through modulation of the efficiency of antigen endocytosis and/or of the direction of successive T helper cell differentiation.
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- 2006
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14. Pharmacokinetics of 9alpha-fluoromedroxyprogesterone acetate in rats: comparison with medroxyprogesterone acetate.
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Kozutsumi D, Kawashima A, Sugimoto T, Kotohda Y, Fujimori S, Takami M, Kohno T, Oikawa T, Sugino E, Choshi T, and Hibino S
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- Administration, Oral, Animals, Antineoplastic Agents administration & dosage, Antineoplastic Agents blood, Area Under Curve, Female, Humans, Injections, Intravenous, Medroxyprogesterone administration & dosage, Medroxyprogesterone blood, Metabolic Clearance Rate, Progesterone administration & dosage, Progesterone blood, Progesterone pharmacokinetics, Progesterone Congeners administration & dosage, Progesterone Congeners blood, Protein Binding, Rats, Rats, Sprague-Dawley, Antineoplastic Agents pharmacokinetics, Medroxyprogesterone pharmacokinetics, Progesterone analogs & derivatives, Progesterone Congeners pharmacokinetics
- Abstract
Medroxyprogesterone acetate (MPA) is widely used in endocrine therapy for breast cancer and other diseases. Recently, it has been demonstrated that 9alpha-fluoromedroxyprogesterone acetate (FMPA) also has anti-tumour activity in chemical-induced rat mammary tumour and its activity is greater than that of MPA. In the present study, the physico-chemical properties of FMPA and MPA and their pharmacokinetics in female rats were investigated. Partition coefficients (log P) of FMPA and MPA were 3.1 and 3.8, respectively, while the solubilities of FMPA and MPA in phosphate buffer saline were 3.8 and 1.1 microg/mL, respectively. When the two agents were intravenously or orally administered into female rats, there was no significant difference between their plasma concentrations. However, unmetabolized drug excreted into urine accounted for 4.7 and 0.7% of the intravenous dose of FMPA and MPA, respectively. The free fraction of FMPA in rat plasma was approximately four times that of MPA. Assuming the well-stirred model, hepatic intrinsic clearances of FMPA and MPA were estimated to be 64 and 293 L/h per kg, respectively. In addition, the free fraction of FMPA in blood is estimated to be higher than that of MPA, which may explain the higher anti-tumour activity.
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- 1999
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15. RT1.P, rat class Ib genes related to mouse TL: evidence that CD1 molecules but not authentic TL antigens are expressed by rat thymus.
- Author
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Matsuura A, Takayama S, Kinebuchi M, Hashimoto Y, Kasai K, Kozutsumi D, Ichimiya S, Honda R, Natori T, and Kikuchi K
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- Amino Acid Sequence, Animals, Base Sequence, Chromosome Mapping, Histocompatibility Antigens Class I genetics, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Molecular Sequence Data, Polymorphism, Genetic, Rats, Recombination, Genetic, Sequence Analysis, DNA, Surface Properties, Antigens, CD1 genetics, Histocompatibility Antigens genetics, Membrane Glycoproteins genetics, Thymus Gland immunology
- Abstract
CD1 and TL were once thought to be genetic homologues because of their thymus-specific expression. We investigated their equivalents in the rat to clarify whether their structure and pattern of expression are conserved in rodents. Two rat class Ib genes, containing 3' sequences very similar to mouse TL, were identified and designated RT1.P. Neither of them, however, can encode ordinary class I molecules due to the accumulation of harmful mutations in the 5' regions that are unique to RT1.P, while the 3' TL-like regions still retain protein-coding capacity. Comparison of the structural organization of three types of TL family genes, which include mouse T3/T18-encoding TL antigens, mouse T1/T16, and rat RT1. P1/P2 pseudogenes, revealed the presence of a clear demarcation between the type-specific and TL-specific sequences at intron 3. This finding suggests that recombination plays an important role in creating the TL family genes in rodents. Characteristic features of TL, such as a low level of polymorphism and linkage to the major histocompatibility complex, were also observed in the rat. On the other hand, rat CD1 molecules were expressed at a high level on the surface of thymocytes. Absence of authentic TL antigens and thymic expression of CD1d molecules in the rat suggest the plasticity and conservation of class Ib genes in rodent evolution. Functions of TL may be substituted with CD1 or other class Ib molecules expressed by rat thymus.
- Published
- 1997
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16. 4,6-Dibromo-3-hydroxycarbazole (an analogue of caffeine-like Ca2+ releaser), a novel type of inhibitor of Ca(2+)-induced Ca2+ release in skeletal muscle sarcoplasmic reticulum.
- Author
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Takahashi Y, Furukawa K, Kozutsumi D, Ishibashi M, Kobayashi J, and Ohizumi Y
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- Animals, Calcium Radioisotopes, Carbolines pharmacology, In Vitro Techniques, Ion-Selective Electrodes, Magnesium pharmacology, Male, Muscle, Skeletal drug effects, Procaine pharmacology, Rabbits, Ruthenium Red pharmacology, Ryanodine, Sarcoplasmic Reticulum drug effects, Caffeine pharmacology, Calcium antagonists & inhibitors, Calcium metabolism, Carbazoles pharmacology, Muscle, Skeletal metabolism, Sarcoplasmic Reticulum metabolism
- Abstract
1. 4,6-Dibromo-3-hydroxycarbazole (DBHC) was synthesized as an analogue of bromoeudistomin D (BED), a powerful Ca2+ releaser, and its pharmacological properties were examined. 2. In Ca2+ electrode experiments, DBHC (100 microM) markedly inhibited Ca2+ release from the heavy fraction of sarcoplasmic reticulum (HSR) induced by caffeine (1 mM) and BED (10 microM). 3. DBHC (0.1 to 100 microM) inhibited 45Ca2+ release induced by Ca2+ from HSR in a concentration-dependent manner. 4. DBHC (100 microM) abolished 45Ca2+ release induced by caffeine (1 mM) and BED (10 microM) in HSR. 5. Inhibitory effects of calcium-induced calcium release (CICR) blockers such as procaine, ruthenium red and Mg2+ on 45Ca2+ release were clearly observed at Ca2+ concentrations from pCa 7 to pCa 5.5, and were decreased at Ca2+ concentrations higher than pCa 5.5 or lower than pCa 7. However, DBHC decreased Ca2+ release induced by Ca2+ over the wide range of extravesicular Ca2+ concentrations. 6. [3H]-ryanodine binding to HSR was suppressed by ruthenium red, Mg2+ and procaine, but was not affected by DBHC up to 100 microM. 7. [3H]-ryanodine binding to HSR was enhanced by caffeine and BED. DBHC antagonized the enhancement in a concentration-dependent manner. 8. 9-[3H]-Methyl-7-bromo-eudistomin D, an 3H-labelled analogue of BED, specifically bound to HSR. Both DBHC and caffeine increased the KD value without affecting the Bmax value, indicating a competitive mode of inhibition. 9. These results suggest that DBHC binds to the caffeine binding site to block Ca2+ release from HSR. This drug is a novel type of inhibitor for the CICR channels in SR and may provide a useful tool for clarifying the Ca2+ releasing mechanisms in SR.
- Published
- 1995
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17. Structure-activity relationship of bromoeudistomin D, a powerful Ca2+ releaser in skeletal muscle sarcoplasmic reticulum.
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Takahashi Y, Furukawa K, Ishibashi M, Kozutsumi D, Ishiyama H, Kobayashi J, and Ohizumi Y
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- Animals, Caffeine metabolism, Caffeine pharmacology, Calcium Channels drug effects, Calcium Channels metabolism, Carbolines chemical synthesis, Male, Muscle Proteins drug effects, Muscle Proteins metabolism, Muscle, Skeletal metabolism, Rabbits, Ryanodine Receptor Calcium Release Channel, Sarcoplasmic Reticulum chemistry, Structure-Activity Relationship, Calcium metabolism, Carbolines pharmacology, Muscle, Skeletal drug effects, Sarcoplasmic Reticulum drug effects
- Abstract
Bromoeudistomin D and 9-methyl-7-bromoeudistomin D which have a beta-carboline skeleton are powerful Ca2+ releasers from skeletal muscle sarcoplasmic reticulum exhibiting caffeine-like properties. We examined the effects of bromoeudistomin D analogues on Ca(2+)-induced Ca2+ release from skeletal muscle sarcoplasmic reticulum. Among bromoeudistomin D analogues, the Ca(2+)-releasing activities of carboline derivatives were higher than those of carbazole derivatives, suggesting that a carboline skeleton is significantly important for the manifestation of Ca(2+)-releasing activity and Ca2+ sensitivity of Ca(2+)-induced Ca2+ release. On the contrary, the analogues which have a carbazole skeleton and bromine at C-6 inhibit both Ca(2+)- and caffeine-induced Ca2+ release. 9-Methyl-substitution of the analogue elevated its Ca(2+)-releasing activity. Moreover, there is a close correlation between the enhancement of [3H]ryanodine binding to sarcoplasmic reticulum by the analogues and the activation of Ca2+ release by them. Bromoudistomin D analogues may provide valuable information about the structure-function relationship of the ryanodine receptor/Ca2+ release channels in skeletal muscle sarcoplasmic reticulum.
- Published
- 1995
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18. Molecular cloning of cDNA encoding rat homologue of CD5 and CD8 alpha: evidence that R1-3B3 and R1-10B5 monoclonal antibodies detect rat CD5 and CD8 antigens, respectively.
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Matsuura A, Murakami T, Kozutsumi D, Kinebuchi M, Onodera K, Kon S, and Kikuchi K
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- Amino Acid Sequence, Animals, Antibodies, Monoclonal, Base Sequence, CD5 Antigens, Cloning, Molecular, Gene Library, Molecular Sequence Data, Rats, Wistar, Transfection, Antigens, CD genetics, CD8 Antigens genetics, DNA, Complementary genetics, Rats genetics, Rats immunology
- Published
- 1993
19. Molecular cloning of rat class I genes related to the mouse TL gene subfamily of the major histocompatibility complex.
- Author
-
Matsuura A, Takayama S, Kozutsumi D, Ichimiya S, Honda R, Shen M, Natori T, and Kikuchi K
- Subjects
- Animals, Biological Evolution, Chromosome Mapping, Cloning, Molecular, Major Histocompatibility Complex, Polymorphism, Restriction Fragment Length, Rodentia genetics, Rodentia immunology, Species Specificity, Genes, MHC Class I, Membrane Glycoproteins genetics, Mice genetics, Mice immunology, Rats genetics, Rats immunology
- Published
- 1993
Catalog
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