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Yamaguchi M, Ehara Y. Effect of essential trace metal on bone metabolism in the femoral-metaphyseal tissues of rats with skeletal unloading: comparison with zinc-chelating dipeptide. Calcif Tissue Int 1996; 59:27-32. [PMID: 8661981 DOI: 10.1007/s002239900081] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The effect of essential trace metals on bone metabolism was investigated in the femoral-metaphyseal tissues obtained from skeletal-unloaded rats. Skeletal unloading was designed by using the model of hindlimb suspension in rats; the animals were fed for 4 days with the unloading. Femoral-metaphyseal tissues were cultured for 24 hours in a medium containing either vehicle (control), nickel, manganese, cobalt, copper, zinc, or zinc-chelating dipeptide (beta-alanyl-L-histidinato zinc; AHZ) in the concentration range of 10(-6) to 10(-4) M. Bone biochemical components (alkaline phosphatase activity, glucose consumption, and DNA content) were significantly decreased by skeletal unloading. The presence of zinc sulfate or AHZ (10(-5) and 10(-4) M) caused a significant increase of alkaline phosphatase activity in the bone tissues from unloaded rats. This effect was not seen by nickel, manganese, cobalt and copper (10(-6) to 10(-4) M). The culture medium glucose was clearly consumed by the bone tissues. This consumption was inhibited by nickel, manganese, or copper (10(-5) and 10(-4) M), while cobalt, zinc, and AHZ had no effect. DNA content in the bone tissues from unloaded rats was significantly increased by all metal compounds (10(-5) M). The effect of AHZ on bone components was greater than zinc sulfate. The AHZ (10(-5) M)-increased alkaline phosphatase activity in the bone tissues from unloaded rats was clearly blocked by the presence of cycloheximide (10(-6) M), staurosporine (10(-7) M), dibucaine (10(-4) M), or okadaic acid (10(-7) M). The present study demonstrates that, of various essential trace metals, zinc compounds have an unique anabolic effect on bone metabolism in the femoral-metaphyseal tissues of rats with skeletal unloading. Zinc-chelating dipeptide may stimulate bone protein synthesis through the mechanism that is involved in protein kinases.
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Shirasaka T, Shimamato Y, Ohshimo H, Yamaguchi M, Kato T, Yonekura K, Fukushima M. Development of a novel form of an oral 5-fluorouracil derivative (S-1) directed to the potentiation of the tumor selective cytotoxicity of 5-fluorouracil by two biochemical modulators. Anticancer Drugs 1996; 7:548-57. [PMID: 8862723 DOI: 10.1097/00001813-199607000-00010] [Citation(s) in RCA: 610] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have focused our attention on the development of a novel form of a tegafur-based [FT; a prodrug of 5-fluorouracil (5-FU)] antitumor agent. We have used two biochemical and pharmacological modulators of 5-FU to improve its overall activity. To potentiate the antitumor activity of FT, 5-chloro-2,4-dihydroxypyridine (CDHP) was used as a potent reversible inhibitor of 5-FU degradation. The reduction of gastrointestinal (GI) toxicity, induced in the host by 5-FU, was modulated by potassium oxonate (Oxo), an inhibitor of orotate phosphoribosyltransferase that catalyzes the phosphorylation of 5-FU, a process believed to be responsible for the toxic effects of 5-FU. When CDHP and FT were simultaneously given orally to Yoshida sarcoma-bearing rats in various molar ratios, the antitumor effect of FT was significantly potentiated by the combination consisting of at least a 0.2 versus 1 molar ratio of CDHP to FT, respectively. This augmentation of an antitumor activity was supported by potent and prolonged inhibition of dihydrouracil dehydrogenase activity (5-FU degrading activities) in the liver of tumor-bearing rats after oral CDHP (0.2:0.8 molar ratio) and furthermore by elevation and over 12 h retention of 5-FU levels in the tumors following combined administration of FT and CDHP at a molar ratio of 1:0.4, respectively. Moreover, to reduce the severe GI injury and subsequent loss of body weight, observed in parallel with an increased antitumor efficacy, Oxo was given orally to Yoshida sarcoma-bearing rats and nude rats xenografted with H-81 human gastric carcinoma, during consecutive administration of the FT-CDHP mixture. Combined treatment with Oxo and FT (1:2 molar ratio) supplemented with 0.4 molar CDHP resulted in protection of body weight loss without affecting the high antitumor efficacy of the FT-CDHP mixture. When [2-14C]FT plus CDHP was administered with Oxo, the 14C-labeled fluoronucleotide content was objectively decreased in the GI tract of the tumor-bearing rats but not in the tumor and bone marrow, which supports our initial hypothesis. Based on these promising data, we propose a suitable formulation of a FT-based anticancer drug, called S-1, and consisting of FT, CDHP and Oxo at a 1:0.4:1 molar ratio and showing tumor-selective cytotoxicity of 5-FU.
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1378
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Sawada K, Ieko M, Notoya A, Tarumi T, Koizumi K, Kitayama S, Nishio H, Fukada Y, Yasukouchi T, Yamaguchi M, Katoh S, Koike T. Role of cytokines in leukemic type growth of myelodysplastic CD34+ cells. Blood 1996; 88:319-27. [PMID: 8704190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The clonal growth of progenitor cells from myelodysplastic syndromes (MDS) can be subdivided into four growth patterns: (1) normal, (2) no growth or low plating efficiency, (3) low colony and high cluster number, and (4) normal or high colony number with a large number of clusters. The former two (1 and 2) can be referred to as nonleukemic patterns and latter two (3 and 4) as leukemic. In a search for a role for cytokines in leukemic-type growth of MDS progenitor cells, marrow CD34+ cells were purified up to 94% for 8 normal individuals and 88% for 12 MDS patients, using monoclonal antibodies and immunomagnetic microspheres (MDS CD34+ cells). The purified CD34+ cells were cultured for 14 days with various combinations of cytokines, including recombinant human macrophage colony-stimulating factor (rM-CSF), granulocyte-CSF (rG-CSF), granulocyte-macrophage-CSF (rGM-CSF), interleukin-3 (rIL-3), and stem cell factor (SCF; a ligand for c-kit) in serum-free medium. The clonal growth of MDS CD34+ cells supported by a combination of all of the above cytokines was subdivided into the two patterns of leukemic or nonleukemic, and then the role of individual or combined cytokines in proliferation and differentiation of MDS CD34+ cells was analyzed in each group. Evidence we obtained showed that SCF plays a central role in the leukemic-type growth of MDS CD34+ cells and that G-CSF, GM-CSF; and/or IL-3 synergize with SCF to increase undifferentiated blast cell colonies and clusters over that seen in normal CD34+ cells. SCF is present in either normal or MDS plasma at a level of nanograms per milliliter, and this physiologic concentration of SCF can stimulate progenitor cells. This means that progenitor cells are continuously exposed to stimulation by SCF in vivo and that MDS leukemic cells have a growth advantage over normal blast cells. This depends, at least in part, on cytokines such as G-CSF, GM-CSF, IL-3, and SCF.
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1379
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Kubota Y, Arai T, Tanaka T, Yamaoka G, Kiuchi H, Kajikawa T, Kawanishi K, Ohnishi H, Yamaguchi M, Takahara J, Irino S. Thrombopoietin modulates platelet activation in vitro through protein-tyrosine phosphorylation. Stem Cells 1996; 14:439-44. [PMID: 8843545 DOI: 10.1002/stem.140439] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To determine the roles of thrombopoietin (TPO) in platelet function in vitro, we examined the effects of TPO on platelet aggregation. Although several proteins in platelets were tyrosine-phosphorylated by TPO treatment, TPO alone was unable to induce platelet aggregation. However, the secondary wave of platelet aggregation induced by adenosine diphosphate (ADP) was enhanced by TPO in a dose-dependent manner. TPO in conjunction with ADP augmented tyrosine phosphorylation of platelet proteins, including tyrosine-phosphorylated proteins induced by TPO alone. Genistein inhibited protein-tyrosine phosphorylation in platelets induced by TPO with ADP and suppressed TPO-enhanced platelet aggregation. Moreover, tyrosine phosphorylation of MAP-kinases induced by TPO alone and TPO with ADP was consistent with TPO-enhanced platelet aggregation. These findings in the present study suggest that signal transduction involved in TPO-enhanced platelet aggregation is mediated in part by tyrosine-phosphorylated proteins, including MAP-kinases, in platelets through TPO-stimulated c-Mpl, TPO receptor.
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1380
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Yamaguchi M, Sawada K, Miyake A. Lipopolysaccharides selectively inhibit mouse placental lactogen-II secretion through stimulation of interleukin-1 alpha (IL-1 alpha) and IL-6 production. J Endocrinol Invest 1996; 19:415-21. [PMID: 8884534 DOI: 10.1007/bf03349885] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To determine whether lipopolysaccharides (LPS) regulate mouse placental lactogen-I (mPL-I), mPL-II, and mouse GHRF (mGHRF) secretion, mouse placental tissue from days 7, 9, and 12 of pregnancy was dispersed with collagenase and the purified trophoblast cells were cultured in a serum-free medium with or without LPS for 5 days. LPS significantly inhibited mPL-II secretion by cells from days 9 and 12 of pregnancy. However, LPS did not affect mPL-II secretion by cells from day 7 of pregnancy, mPL-I secretion by cells from days 7 and 9 of pregnancy, or mGHRF secretion by cells from day 12 of pregnancy. The inhibitory effect of LPS on mPL-II secretion by cells from day 12 of pregnancy was dose-dependent. Steady-state levels of mPL-II mRNA were significantly reduced by incubation of placental cells from day 12 of pregnancy with LPS. The inhibitory effect of LPS on mPL-II secretion was abolished by the addition of antibodies to IL-1 alpha and IL-6. These findings suggest that LPS selectively inhibit mPL-II secretion, at least partly through increases in IL-1 and IL-6 production, after midpregnancy.
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1381
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Kashiba-Iwatsuki M, Yamaguchi M, Inoue M. Role of ascorbic acid in the metabolism of S-nitroso-glutathione. FEBS Lett 1996; 389:149-52. [PMID: 8766819 DOI: 10.1016/0014-5793(96)00560-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Although nitric oxide (NO) has been known to generate S-nitroso-thiols (RSNOs), dynamic aspects of their metabolism remain to be elucidated. The present work reports the reactivity of S-nitroso-glutathione (GS-NO) with various compounds with reducing activity. Kinetic analysis revealed that among various reagents tested, ascorbic acid showed a potent activity to decompose GS-NO to glutathione and oxidized products of NO. During the reaction of GS-NO and ascorbic acid, monodehydroascorbate was found to appear as an intermediate. These results suggest that ascorbic acid might be an important modulator for RS-NO metabolism.
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1382
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Fujisaki H, Kumekawa K, Yamaguchi M, Yoshimura M. Particle production and dissipative cosmic field. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1996; 53:6805-6812. [PMID: 10019966 DOI: 10.1103/physrevd.53.6805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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1383
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Takahashi Y, Yamaguchi M, Hirose F, Cotterill S, Kobayashi J, Miyajima S, Matsukage A. DNA replication-related elements cooperate to enhance promoter activity of the drosophila DNA polymerase alpha 73-kDa subunit gene. J Biol Chem 1996; 271:14541-7. [PMID: 8662923 DOI: 10.1074/jbc.271.24.14541] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
An analysis was carried out on the promoter region of the Drosophila DNA polymerase alpha 73-kDa subunit gene and the factor(s) activating the promoter. Transcription initiation sites were newly identified in the region downstream of the previously determined sites. Full promoter activity resided within the region from -285 to +129 base pairs with respect to the newly determined major site. Within this region, we found three sequences identical or similar to the DNA replication-related element (DRE), 5'-TATCGATA, which is known as a common promoter-activating element for the Drosophila DNA polymerase alpha 180-kDa subunit gene and the proliferating cell nuclear antigen gene. These sites were located at positions -77 to -70 (DREalpha-I), -44 to -37 (DREalpha-II), and +3 to +10 (DREalpha-III). Footprinting analysis using the recombinant DRE-binding factor (DREF) or Kc cell nuclear extract demonstrated that DREF can bind to all three DRE-related sites. Introduction of mutation in even one of the three DRE-related sequences caused extensive reductions of the promoter activity and also the DREF-binding activity of the promoter-containing fragment. The results indicate that the three DREF-binding sites cooperate to enhance promoter activity of the DNA polymerase alpha 73-kDa subunit gene.
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1384
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Abstract
A highly malignant case of intrathyroidal thymic carcinoma showing morphological and biochemical evidence identical with mediastinal thymoma is presented. A 32-year-old female, who had previously undergone total colectomy with ileo-proctostomy due to familial adenomatous polypnosis, was operated on for a tumor (3.4 x 4.5 cm) originating from the left thyroid lobe. A minute focus (diam. 0.8 cm) of papillary adenocarcinoma also existed in the upper pole of the right lobe. The main tumor was morphologically an epithelial thymoma with scanty lymphocyte intermixing and showed medullary differentiation with apparent Hassall's corpuscles. Mitosis was frequent and numerous tumor thrombi were in the subcapsular veins. Five months after the total thyroidectomy and lymph node dissection, a subcutaneous recurrence of the tumour (diam. 2.3 cm) appeared in the anterior cervical region. The cystic contents of the recurrent tumor revealed a high titer of thymosin alpha 1-Other organs, including thymus, lungs, and adrenals, had all been free of neoplastic changes clinically and radiologically for 5 months after her first admission until the local tumor recurrence.
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1385
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Hirose F, Yamaguchi M. [Transcriptional regulation of DNA replication-related genes during Drosophila melanogaster development]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 1996; 41:1022-32. [PMID: 8741622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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1386
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Ikegami S, Tomita M, Honda S, Yamaguchi M, Mizukawa R, Suzuki Y, Ishii K, Ohsawa S, Kiyooka N, Higuchi M, Kobayashi S. Effect of boiled barley-rice-feeding in hypercholesterolemic and normolipemic subjects. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 1996; 49:317-28. [PMID: 8983058 DOI: 10.1007/bf01091981] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Barley contains approximately 10% dietary fiber and is easily cooked with rice, the dominant cereal in Japan, to increase the intake of dietary fiber. This research involved three experiments to examine the influence of barley on blood lipids in human subjects. All subjects received a boiled barley-rice (50/50 w/w mix) supplement two times per day in place of rice for 2 or 4 weeks. In the normolipemic subjects, serum lipids were unaffected by the ingestion of barley for 4 weeks. In twenty hypercholesterolemic men aged 41 +/- 5 years, the ingestion of barley was associated with a significant fall in serum total cholesterol, LDL-cholesterol, phospholipids and LDL and VLDL-lipoproteins. In seven mildly hypercholesterolemic women aged 56 +/- 7 years, a significant improvement of serum lipid profiles was observed. The present study suggests the possibility that the ingestion of barley-rice could lower serum lipids in hypercholesterolemic subjects.
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1387
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Yamaguchi M, Hirai K, Ohta K, Suzuki K, Kitani S, Takaishi T, Ito K, Ra C, Morita Y. Nonreleasing basophils convert to releasing basophils by culturing with IL-3. J Allergy Clin Immunol 1996; 97:1279-87. [PMID: 8648024 DOI: 10.1016/s0091-6749(96)70196-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The extent of basophil histamine release initiated by IgE cross-linking stimuli has been known to vary greatly among donors. Studies on anti-IgE nonreleasing basophils are useful in understanding the IgE-specific control mechanism of mediator release. We attempted to determine (1) whether a mutation of Fc epsilon RI is present in nonreleasing basophils and (2) whether treatment with IL-3 converts anti-IgE nonreleasing basophils to releasing basophils. Basophils were purified from normal human blood and donors were divided into releasers (maximal histamine release > 5%) and nonreleasers (< 5%). The mutation of Fc epsilon RI alpha, beta, and gamma was evaluated by reverse transcriptase-polymerase chain reaction, and the DNA sequence was determined from amplified polymerase chain reaction products. Although antibodies against Fc epsilon RI failed to cause histamine release in anti-IgE nonreleasing basophils, no primary structural change of Fc epsilon RI was observed in nonreleaser basophils. After culturing with IL-3 for 7 days, nonreleasing basophils released histamine in response to anti-IgE, and dose-response curves of anti-IgE were equal in both releasers and nonreleasers. The conversion of nonreleasing basophils to releasing basophils was evident after 3 days of culture with IL-3. These findings indicate that nonreleasing basophils have recoverable defect(s) in the signal transduction pathway after IgE cross-linking.
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1388
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Hiida M, Ushiyama O, Suzuki N, Ohta A, Nagasawa K, Yamaguchi M. [The effect of beraprost sodium on the Raynaud's phenomenon]. NIHON RINSHO MEN'EKI GAKKAI KAISHI = JAPANESE JOURNAL OF CLINICAL IMMUNOLOGY 1996; 19:193-200. [PMID: 8810544 DOI: 10.2177/jsci.19.193] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We investigated the effect of beraprost sodium (BPS) on the Raynaud's phenomenon on 15 patients with systemic sclerosis, 3 with mixed connective tissue disease and 1 with Raynaud's disease, respectively. After 12 weeks of administration of 60 micrograms/d BPS, the duration and the incidence of the Raynaud's symptom were significantly reduced and the dermal temperature on the fingers was found to be elevated. Of the parameters which are known to reflect vascular endothelial damages such as tissue plasminogen activator (t-PA), von Willebrand's factor (vWF) and endothelin, the plasma level of t-PA was significantly reduced by BPS. Furthermore, the capillary loop in the nail bed of the fingers seemed to increase in one patient by the treatment with BPS. These results suggest that BPS has a capacity to repair peripheral vascular damages resulting in the improvement of Raynaud's phenomenon.
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1389
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Shirahata A, Ono O, Yanaga Y, Yamaguchi M, Oosato K. Comprehensive care for hemophiliacs--activities of North Kyushu Hemophilia Center at the University Hospital of Occupational and Environmental Health, Japan. J UOEH 1996; 18:141-50. [PMID: 8701115 DOI: 10.7888/juoeh.18.141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
One of our objectives in establishing the Hemophilia Center was to create a model of a total care system for chronic diseases which develop in the childhood and continue through adulthood. We also believe that the comprehensive medical care system should be introduced not only for the care of hemophiliacs but also for those with every chronic refractory disease. It may be a surprise that in a university hospital, which is likely to lack cooperation between departments, this kind of cross sectional support system, even extending to activities outside the hospital, has been continued. This success owes much to the understanding and consideration by successive Directors of the Hospital and the Professors (Directors) of every department, the enthusiastic efforts by members of the Center who have continued their volunteer work for the purpose of improving the QOL of patients, and the cooperation by students of the Volunteer Study Club. We also have to mention the advice and guidance by Dr. Minoru Inagaki (now at the National Children's Hospital) who established the first substantial hemophilia center in Ogikubo Hospital, and Dr. Kaneo Yamada, present Visiting Professor in the Faculty of Medicine, St. Marianna University. We would like to thank every one who has supported the activities of the Center. Finally, we strongly hope that this total care system will become popular among those responsible for caring of patients with other chronic refractory diseases.
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1390
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Yamaguchi M, Takada M, Nozaki O, Ito M, Furukawa Y. Preparation of corn peptide from corn gluten meal and its administration effect on alcohol metabolism in stroke-prone spontaneously hypertensive rats. J Nutr Sci Vitaminol (Tokyo) 1996; 42:219-31. [PMID: 8866258 DOI: 10.3177/jnsv.42.219] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Corn peptide (CP) was prepared from corn gluten meal by proteolysis with alkaline protease from alkalophilic Bacillus A-7. Free amino acids were not found in the CP product. Gel filtration on a Shodex OH-packed column revealed that the molecular weight distribution of the CP was less than about 2,000, characteristic of dipeptides to decapeptides, i.e. oligopeptides. The amino acid pattern of CP was similar to that of corn gluten meal, which was rich in alanine and branched-chain amino acids, but poor in basic amino acids. The effect of the CP administration on alcohol metabolism was examined with SHR-SP, which were given ethanol orally through a gastric tube at the rate of 1.0 g/kg. Prior administration of CP at 1.0 g/kg resulted in fast disappearance of ethanol and its oxidative product acetaldehyde from the blood relative to the control without administration. Hence, it is suggested that CP, rather than its constituent amino acids such as alanine and proline, effectively takes part in enhancing the metabolism of ethanol as well as acetaldehyde.
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1391
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Morita S, Fukase M, Yamaguchi M, Morita Y. Substrate specificity of a novel serine protease from soybean [Glycine max (L.) Merrill]. J Biochem 1996; 119:1094-9. [PMID: 8827443 DOI: 10.1093/oxfordjournals.jbchem.a021353] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The substrate specificity of a novel serine protease isolated from soybean seeds, cultivar Keburi, was investigated using various peptide-MCAs and several neuropeptides involving single and paired basic amino acid sequences. The protease was quite specific for arginine residue at the P1 site of the active center, and it recognized paired Arg-Arg and cleaved at the linkage between Arg-Arg or after Arg-Arg in peptide and protein molecules. This is the first protease in plant tissues which resembles in substrate specificity the arginine-specific serine proteinases from porcine gastric and intestinal mucosa, recognizing paired basic amino acid sequences.
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1392
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Ikeda H, Yamaguchi M, Sugai S, Aze Y, Narumiya S, Kakizuka A. Expanded polyglutamine in the Machado-Joseph disease protein induces cell death in vitro and in vivo. Nat Genet 1996; 13:196-202. [PMID: 8640226 DOI: 10.1038/ng0696-196] [Citation(s) in RCA: 416] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Recently, we identified a novel gene, MJD1, which contains an expanded CAG triplet repeat in Machado-Joseph disease. Here we report the induction of apoptosis in cultured cells expressing a portion of the MJD1 gene that includes the expanded CAG repeats. Cell death occurs only when the CAG repeat is translated into polyglutamine residues, which apparently precipitate in large covalently modified forms. We also created ataxic transgenic mice by expressing the expanded polyglutamine stretch in Purkinje cells. Our results demonstrate the potential involvement of the expanded polyglutamine as the common aetiological agent for inherited neurodegenerative diseases with CAG expansions.
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1393
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Yamaguchi M, Kishi S. Zinc compounds inhibit osteoclast-like cell formation at the earlier stage of rat marrow culture but not osteoclast function. Mol Cell Biochem 1996; 158:171-7. [PMID: 8817479 DOI: 10.1007/bf00225843] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effect of zinc compounds on osteoclast-like cell formation in rat marrow culture in vitro was investigated. The bone marrow cells were cultured for 7 days in alpha-minimal essential medium containing a well-known bone resorbing hormone (1, 25-dihydroxyvitamin D3 and parathyroid hormone [1-34]). Osteoclast-like cell formation was estimated by staining for tartrate-resistant acid phosphatase (TRACP), a marker enzyme of osteoclasts. The presence of 1, 25-dihydroxyvitamin D3 (10(-8) M) or parathyroid hormone (PTH; 10(-8) M) induced a remarkable increase in osteoclast-like multinucleated cells (MNC). These increases were clearly inhibited by the presence of zinc sulfate or zinc-chelating dipeptide (beta-alanyl-L-histidinato zinc; AHZ) in the concentration range of 10(-7) to 10(-5) M. The inhibitory effect was seen at the earlier stage of osteoclast-like MNC formation. However, zinc compounds (10(-6) M) did not have an effect on PTH (10(-8) M)-induced osteoclast-like cell formation in the presence of EGTA (5 x 10(-4) M), dibucaine (10(-5) M) or staurosporine (10(-9) M). Moreover, when osteoclasts isolated from rat femoral-diaphyseal tissues were cultured for 24 h in the presence of zinc compounds (10(-7) to 10(-5) M), the compounds did not have an effect on cell numbers or lysosomal enzymes activity (acid phosphatase and beta-glucuronidase) in the cells. The present study clearly demonstrates that zinc compounds inhibit osteoclast-like cell formation at the earlier stage with differentiation of marrow cells.
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1394
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Yamaguchi M, Shiraishi T, Hirama M. Asymmetric Michael Addition of Malonate Anions to Prochiral Acceptors Catalyzed by l-Proline Rubidium Salt. J Org Chem 1996. [DOI: 10.1021/jo960216c] [Citation(s) in RCA: 223] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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1395
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Hanahisa Y, Yamaguchi M. Characterization of calcium accumulation in the brain of rats administered orally calcium: the significance of energy-dependent mechanism. Mol Cell Biochem 1996; 158:1-7. [PMID: 8791278 DOI: 10.1007/bf00225876] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The characterization of calcium accumulation in the brain of rats administered orally calcium chloride solution was investigated. Rats received a single oral administration of calcium (15-50 mg/100 g body weight), and they were sacrificed by bleeding between 15 and 120 min after the administration. The administration of calcium (50 mg/100 g) produced a significant increase in serum calcium concentration and a corresponding elevation of brain calcium content, indicating that the transport of calcium into the brain is associated with the elevation of serum calcium levels. The increase in brain calcium content by calcium administration was not appreciably altered by the pretreatment with Ca2+ channel blockers (verapamil or diltiazem with the doses of 1.5 and 3.0 mg/100 g). In thyroparathyroidectomized rats, the administration of calcium (50 mg/100 g) caused a significant increase in brain calcium content, indicating that calcium-regulating hormones do not participate in the brain calcium transport. Now, brain calcium content was clearly elevated by fasting (overnight), although serum calcium level was not significantly altered. Calcium administration to fasted rats induced a further elevation of brain calcium content as compared with that of control (fasted) rats. The fasting-induced increase in brain calcium content was appreciably restored by refeeding. This restoration was also seen by the oral administration of glucose (0.4 g/100 g) to fasted rats. The present study demonstrates that serum calcium is transported to brain, and that the increased brain calcium is released promptly. The release of calcium from brain may be involved in energy metabolism, and this release may be weakened by the reduction of glucose supply into brain. The finding suggests a physiological significance of energy-dependent mechanism in the regulation of brain calcium.
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1396
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Takahashi H, Yamaguchi M. Activatory effect of regucalcin on hepatic plasma membrane (Ca(2+)-Mg2+)-ATPase is impaired by liver injury with carbon tetrachloride administration in rats. Mol Cell Biochem 1996; 158:9-16. [PMID: 8791279 DOI: 10.1007/bf00225877] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The alteration of the plasma membrane (Ca(2+)-Mg2+)-ATPase activity in the liver of rats administered orally carbon tetrachloride (CCl4) solution was investigated. Rats received a single oral administration of CCl4 (10, 25 and 50%, 1.0 ml/100 g body weight), and 3 or 24 h later they were sacrificed. CCl4 administration caused a remarkable elevation of liver calcium content and a corresponding increase in liver plasma membrane (Ca(2+)-Mg2+)-ATPase activity, indicating that the increased Ca2+ pump activity is partly involved in calcium accumulation in liver cells. Moreover, the participation in regucalcin, which is an intracellular activating factor on the enzyme, was examined by using anti-regucalcin IgG. The plasma membrane (Ca(2+)-Mg2+)-ATPase activity increased by CCl4 administration was not entirely inhibited by the presence of anti-regucalcin IgG (1.0 and 2.5 ug/ml) in the enzyme reaction mixture. However, the effect of regucalcin (0.25-1.0 uM) to activate (Ca(2+)-Mg2+)-ATPase in the liver plasma membranes of normal rats was not revealed in the liver plasma membranes obtained from CCl4-administered rats. Also, the effect of regucalcin was not seen when the plasma membranes were washed with 1.0 mM EGTA, indicating that the disappearance of regucalcin effect is not dependent on calcium binding to the plasma membranes due to liver calcium accumulation. Now, the presence of dithiothreitol (5 mM) or heparin (20 ug/ml) caused a remarkable elevation of the plasma membrane (Ca(2+)-Mg2+)-ATPase activity in the liver obtained from CCl4-administered rats. Thus, the regucalcin effect differed from that of dithiothreitol or heparin. The present study suggests that the impairment of regucalcin effect on Ca2+ pump activity in liver plasma membranes is partly contribute to hepatic calcium accumulation induced by liver injury with CCl4 administration.
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1397
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Iizuka R, Ishida J, Yoshitake T, Nakamura M, Yamaguchi M. Assay for tryptophan hydroxylase activity in rat brain by high-performance liquid chromatography with fluorescence detection. Biol Pharm Bull 1996; 19:762-4. [PMID: 8741591 DOI: 10.1248/bpb.19.762] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A highly sensitive and selective liquid chromatographic (HPLC) method with post-column fluorescence detection has been developed for the determination of tryptophan 5-monooxygenase activity in rat brain tissue homogenate. 5-Hydroxytryptophan, formed enzymatically from tryptophan (incubation time, 20 min), is extracted with perchloric acid and determined by HPLC. Detection is performed fluorometrically after post-column derivatization by a reaction with benzylamine in the presence of potassium hexacyanoferrate (III). The lower limit of detection for 5-hydroxytryptophan formed enzymatically is 100 fmol at a signal-to-noise ratio of three.
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1398
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Yamaguchi M, Mizutani M, Miwa K, Ono T, Suku H, Kita K. [So-called NK cell lymphoma]. [RINSHO KETSUEKI] THE JAPANESE JOURNAL OF CLINICAL HEMATOLOGY 1996; 37:417-421. [PMID: 8691587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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1399
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Tanaka K, Okamoto K, Inui H, Minonishi Y, Yamaguchi M, Koiwa M. Elastic constants and their temperature dependence for the intermetallic compound Ti3Al. ACTA ACUST UNITED AC 1996. [DOI: 10.1080/01418619608245145] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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1400
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Morita S, Fukase M, Yamaguchi M, Fukuda Y, Morita Y. Purification, characterization, and crystallization of single molecular species of beta-conglycinin from soybean seeds. Biosci Biotechnol Biochem 1996; 60:866-73. [PMID: 8704316 DOI: 10.1271/bbb.60.866] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Four major molecular species of beta-conglycinin, alpha 3, alpha 2 beta, alpha beta 2, and beta 3, were isolated and purified from seeds of an alpha' subunit-deficient strain of soybeans (Glycine max). All components were found to be homogeneous by high pressure liquid chromatography, SDS-polyacrylamide gel electrophoresis, and amino acid and amino terminal sequence analyses. The amino acid compositions of the alpha 3 and beta 3 components agreed fairly well with the compositions deduced from the cDNA sequences, and all of the components were highly glycosylated. The alpha 3 and beta 3 components were compared regarding their secondary structures. The secondary structure of the alpha 3 component deduced from CD measurements showed a higher alpha-helix content than that of the beta 3 component. The beta 3 component was crystallized by decreasing the ionic strength from 0.5 to 0.14 in phosphate buffer, pH 7.3, and the crystals grew to a size (1.0 mm x 0.2 mm x 0.2 mm) suitable for X-ray crystallographic analysis. A preliminary X-ray analysis showed that the crystal belonged to an orthorhombic crystal system having the space group P2(1)2(1)2(1) and unit cell dimensions of a = 185.1 A, b = 107.9 A, and c = 97.6 A.
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