76
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Kamei K, Maeda N, Ogino R, Koyama M, Nakajima M, Tatsuoka T, Ohno T, Inoue T. New 5-HT1A receptor agonists possessing 1,4-benzoxazepine scaffold exhibit highly potent anti-ischemic effects. Bioorg Med Chem Lett 2001; 11:595-8. [PMID: 11229779 DOI: 10.1016/s0960-894x(01)00008-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A series of new 3-substituted-4-(4-aminobutyl)-1,4-benzoxazepin-5(4H)-one derivatives (1-5) which showed a very high affinity for 5-HT1A receptor with good selectivity over dopamine D2 receptor was synthesized. Among these compounds, 3-chloro-4-[4-[4-(2-pyridinyl)-1,2,3,6-tetrahydropyridin-1-yl]butyl]-1,4-benzoxazepin-5(4H)-one (5: SUN N4057) exhibited remarkable neuroprotective activity in a transient middle cerebral artery occlusion (t-MCAO) model.
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77
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Ito H, Kamei K, Iwamoto I, Inaguma Y, Nohara D, Kato K. Phosphorylation-induced change of the oligomerization state of alpha B-crystallin. J Biol Chem 2001; 276:5346-52. [PMID: 11096101 DOI: 10.1074/jbc.m009004200] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
alphaB-crystallin in cells can be phosphorylated at three serine residues in response to stress or during mitosis (Ito, H., Okamoto, K., Nakayama, H., Isobe, T., and Kato, K. (1997) J. Biol. Chem. 272, 29934-29941 and Kato, K., Ito, H., Kamei, K., Inaguma, Y., Iwamoto, I., and Saga, S. (1998) J. Biol. Chem. 273, 28346-28354). In the present study, we determined effects of phosphorylation of alphaB-crystallin on its oligomerization state, mainly by using site-directed mutagenesis, in which all three phosphorylation sites were substituted with aspartate to mimic the phosphorylation state (3D-alphaB). From results of sucrose density gradient centrifugation, we found that wild type alphaB-crystallin (wt-alphaB) and 3D-alphaB sedimented in fractions corresponding to apparent molecular masses of about 500 and 300 kDa, respectively. Chaperone-like activity of 3D-alphaB was significantly weaker than that of wt-alphaB. When wt-alphaB and 3D-alphaB were expressed in COS-m6 cells, they sedimented at positions corresponding to apparent molecular masses of about 500 and 100 kDa, respectively. In U373 MG human glioma cells, alphaB-crystallin was observed as large oligomers with apparent molecular masses about 500 kDa and the oligomerization size was reduced after phosphorylation induced by phorbol 12-myristate 13-acetate and okadaic acid. Coexpression of luciferase and wt-alphaB or 3D-alphaB in Chinese hamster ovary cells caused protection of the enzyme from heat inactivation although the degree of protection with 3D-alphaB was less than that with wt-alphaB. From these observations, it is suggested that phosphorylation of alphaB-crystallin causes dissociation of large oligomers to smaller sizes molecules and reduction of chaperone-like activity, like in the case of HSP27.
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78
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Wu X, Kamei K, Sato H, Sato SI, Takano R, Ichida M, Mori H, Hara S. High-level expression of human acidic fibroblast growth factor and basic fibroblast growth factor in silkworm (Bombyx mori L.) using recombinant baculovirus. Protein Expr Purif 2001; 21:192-200. [PMID: 11162406 DOI: 10.1006/prep.2000.1358] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A hybrid of Autographa californica nuclear polyhedrosis virus and Bombyx mori nuclear polyhedrosis virus, which is infectious to both Spodoptera frugiperda and Bombyx mori, was prepared in our previous study. Two recombinant hybrid baculoviruses, carrying cDNAs of human acidic and basic fibroblast growth factors, respectively, were successfully constructed in this study, for the large-scale production of human aFGF and bFGF using silkworm as host. These recombinant viruses were used to inoculate silkworm larvae. After the infection, the recombinant proteins were not found in the hemolymph. Such nonsecretion from cells has also been observed in the established insect cell lines, Sf21 and Tn-5. Tissue distribution analysis indicated that the expressed products were mainly located in fat body and the production of the recombinant aFGF and bFGF was maximal at around 80 h postinfection. Therefore, silkworm larvae infected with recombinant viruses were dissected and fat bodies were collected for the purification of recombinant aFGF and bFGF. The expression levels in both cases were estimated to be as high as approximately 600-700 microg per larva. Furthermore, the recombinant proteins were characterized and their biological activities were evaluated by in vitro bioassay using cell culture.
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79
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Kato K, Inaguma Y, Ito H, Iida K, Iwamoto I, Kamei K, Ochi N, Ohta H, Kishikawa M. Ser-59 is the major phosphorylation site in alphaB-crystallin accumulated in the brains of patients with Alexander's disease. J Neurochem 2001; 76:730-6. [PMID: 11158243 DOI: 10.1046/j.1471-4159.2001.00038.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The phosphorylation state of alphaB-crystallin accumulated in the brains of two patients with Alexander's disease (one infantile and one juvenile type) was determined by means of SDS-PAGE or isoelectric focusing of soluble and insoluble fractions of brain extracts and subsequent western blot analysis with specific antibodies against alphaB-crystallin and each of three phosphorylated serine residues. The level of mammalian small heat shock protein of 25-28 kDa (Hsp27) in the same fraction was also estimated by western blot analysis. The majority of alphaB-crystallin was detected in the insoluble fraction of brain homogenates and phosphorylation was preferentially observed at Ser-59 in both cases. A significant level of phosphorylation at Ser-45 but not Ser-19 was also detected. Hsp27 was found at considerable levels in the insoluble fractions. alphaB-crystallin and phosphorylated forms were detected in the cerebrospinal fluid of patient with the juvenile type. AlphaB-crystallin and phosphorylated forms were also detectable at considerable levels in the insoluble fraction of brain homogenates from patients with Alzheimer's disease and aged controls. The phosphorylation site was mostly at Ser-59 in all cases. Immunohistochemically, alphaB-crystallin was stained in Rosenthal fibers in brains of patients with Alexander's disease and their peripheral portions were immunostained with antibodies recognizing phosphorylated Ser-59. These results indicate that the major phosphorylation site in alphaB-crystallin in brains of patients with Alexander's disease or Alzheimer's disease as well as in aged controls is Ser-59.
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80
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Muneoka K, Ogawa T, Kamei K, Mimura Y, Kato H, Takigawa M. Nicotine exposure during pregnancy is a factor which influences serotonin transporter density in the rat brain. Eur J Pharmacol 2001; 411:279-82. [PMID: 11164385 DOI: 10.1016/s0014-2999(00)00925-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We examined the effects of nicotine exposure during pregnancy on serotonin transporter (SERT) expression in the brain. Nicotine (6 mg/kg/day) was administered to pregnant rats via subcutaneous injections or infusion pumps. Irrespective of the route of administration, nicotine increased SERT density in the forebrain on postnatal day 22, but not in the other brain regions. Our results suggest that nicotine use by pregnant women might be an environmental factor influencing SERT expression in their children.
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81
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Kamei K, Matsuoka H, Furuhata SI, Fujisaki RI, Kawakami T, Mogi S, Yoshihara H, Aoki N, Ishii A, Shibuya T. Anti-malarial activity of leaf-extract of hydrangea macrophylla, a common Japanese plant. ACTA MEDICA OKAYAMA 2000; 54:227-32. [PMID: 11061572 DOI: 10.18926/amo/32291] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
To find a new anti-malarial medicine derived from natural resources, we examined the leaves of 13 common Japanese plants in vitro. Among them, a leaf-extract of Hydrangea macrophylla, a common Japanese flower, inhibited the parasitic growth of Plasmodium falciparum. The IC50 of Hydrangea macrophylla leaf extract to Plasmodium falciparum was 0.18 microg/ml. The IC50 to NIH 3T3-3 cells, from a normal mouse cell line, was 7.2 microg/ml. Thus, selective toxicity was 40. For the in vivo test, we inoculated Plasmodium berghei, a rodent malaria parasite, to ddY mice and administered the leaf-extract of Hydrangea macrophylla (3.6 mg/0.2 ml) orally 3 times a day for 3 days. Malaria parasites did not appear in the blood of in the treated mice, but they did appear in the control group on day 3 or 4 after inoculation with the parasites. When leaf extract was administered to 5 mice 2 times a day for 3 days, malaria parasites did not appear in 4 of the mice but did appear in 1 mouse. In addition, the leaf-extract was administered orally 3 times a day for 3 days to Plasmodium berghei infected mice with a parasitemia of 2.7%. In the latter group, malaria parasites disappeared on day 3 after initiating the treatment, but they appeared again after day 5 or 6. Although we could not cure the mice entirely, we confirmed that the Hydrangea macrophylla leaf extract did contain an anti-malarial substance that can be administered orally.
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82
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Tamaoka Y, Orikasa H, Sumi Y, Sakakura K, Kamei K, Nagatani M, Ezawa S. Direct effect of danazol on endometrial hyperplasia in adenomyotic women: treatment with danazol containing intrauterine device. Hum Cell 2000; 13:127-33. [PMID: 11197774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
It is well known that danazol has a direct effect on endometriosis tissue and cell. We have been treating adenomyotic women with danazol containing intrauterine device (D-IUD) from June 1993 to August 2000 and significant decrease of dysmenorrhea and serum CA-125 levels were observed. Of fifty-nine adenomyotic women, eight women were also diagnosed by endometrial biopsy as endometrial hyperplasia and one woman was diagnosed as atypical endometrial hyperplasia. In these endometrial hyperplastic patients, endometrial tissues were obtained before insertion and at the time of removal or exchange of D-IUD and examined pathologically. In all of the 9 women, histopathological findings of endometrial hyperplasia disappeared after D-IUD treatment. In particular, in one patient, findings of atypical endometrial hyperplasia also disappeared after D-IUD treatment. She is now closely observed at our clinic using D-IUD. By these evidences, we postulate that D-IUD is one of the treatment choices of endometrial hyperplasia given exposure of the endometrium to such an extraordinary high concentration of danazol released by D-IUD and avoidance of adverse effects of oral danazol or general administration of GnRH and progesterone. In particular, in atypical endometrial hyperplasia case, its mechanisms might give great benefit to patient. However, mechanisms of direct effect of danazol on endometrial hyperplasia remain to be elucidated in the future study.
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83
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Kariya Y, Kyogashima M, Suzuki K, Isomura T, Sakamoto T, Horie K, Ishihara M, Takano R, Kamei K, Hara S. Preparation of completely 6-O-desulfated heparin and its ability to enhance activity of basic fibroblast growth factor. J Biol Chem 2000; 275:25949-58. [PMID: 10837484 DOI: 10.1074/jbc.m004140200] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although regioselective removal of 6-O-sulfate groups of heparin has been undertaken by several researchers, complete 6-O-desulfation with little side reaction has not been attained successfully. In this work, a modified method with a certain silylating reagent, N-methyl-N-(trimethylsilyl)trifluoroacetamide, has been established to produce completely 6-O-desulfated heparin with few other chemical changes. The degrees of 6-O-desulfation were estimated by means of chemical disaccharide analyses and/or (13)C NMR spectra. Although the completely 6-O-desulfated heparin lost about 20% of 2-O-sulfate groups, any other chemical changes and depolymerization were not detected. The completely 6-O-desulfated heparin displayed strong inhibition of COS-1 cell adhesion to basic fibroblast growth factor (bFGF)-coated well in a dose-dependent manner, as was clarified by the competitive cell-adhesion assay. Furthermore, the completely 6-O-desulfated heparin was shown to promote in vitro A31 fibroblast proliferation in a dose-dependent manner in the presence of bFGF. These results suggest that signal transduction through bFGF/bFGF receptor in A31 cells occurs in the absence of 6-O-sulfate groups in heparin. The involvement of 6-O-sulfate group(s) of heparin/heparan sulfate in the promotion of bFGF mitogenic activity was reported by several groups. This discrepancy between our results and those of other groups would be due to the differences in molecular size of heparin/heparan sulfate derivatives and/or cell species used for the assay.
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84
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Kamei K, Sato S, Hamato N, Takano R, Ohshima K, Yamamoto R, Nishino T, Kato H, Hara S. Effect of P(2)' site tryptophan and P(20)' site deletion of Momordica charantia trypsin inhibitor II on inhibition of proteinases. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1480:6-12. [PMID: 11004551 DOI: 10.1016/s0167-4838(00)00102-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Momordica charantia trypsin inhibitor II (MCTI-II) inhibits the amidolytic activity of factor Xa with a K(i) value 10-100-fold smaller than those of other squash family inhibitors. It also inhibits factor X activation mediated by factor VIIa-tissue factor complex or factor IXa. Comparison of other squash family inhibitors reveal Trp at position 7 (P(2)') and a deletion at position 25 (P(20)') are characteristics of MCTI-II. In order to elucidate the effect of these positions on the inhibitory activity, we chemically synthesized three inhibitors: S-MCTI-II whose amino acid sequence is identical to natural MCTI-II, S-MCTI-II(7L) whose P(2)'(Trp) is substituted with Leu, and S-MCTI-II(25N) whose P(20)'(deletion) is filled with Asn. The dissociation constants of the complexes of human factor Xa with S-MCTI-II, S-MCTI-II(7L), and S-MCTI-II(25N) were 1.3x10(-6) M, 2.8x10(-5) M, and 7.3x10(-6) M, respectively. They inhibited factor X activation mediated by factor VIIa with the same degree. As in the case of natural MCTI-II, S-MCTI-II suppressed factor X activation mediated by factor IXa, while S-MCTI-II(7L) and S-MCTI-II(25N) did not. Both the Trp at the P(2)' position and deletion at the P(20)' position are thus likely required for the inhibition of factor Xa, trypsin, and factor IXa, while these two positions do not affect factor X activation initiated by the factor VIIa-tissue factor complex.
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85
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Sato H, Nakajima K, Maeno Y, Kamaishi T, Kamata T, Mori H, Kamei K, Takano R, Kudo K, Hara S. Expression of YAV proteins and vaccination against viral ascites among cultured juvenile yellowtail. Biosci Biotechnol Biochem 2000; 64:1494-9. [PMID: 10945269 DOI: 10.1271/bbb.64.1494] [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: 11/08/2022]
Abstract
Yellowtail ascites virus (YAV) is a member of the family Birnaviridae and causes viral ascites among juvenile yellowtail (Seriola quinqueradiata). We have reported the cloning and expression of two viral cDNAs, the first being segment A encoding a polyprotein of viral capsid proteins (VP2 and VP3) and a protease (NS), and the second being VP2-epitope encoding serotype-specific epitope region on VP2, using a baculovirus expression system. Another viral cDNA encoding a polyprotein of NS and VP3 was cloned and expressed in this study. For the expression of NS/VP3 (YAV nt 1626 to 3066) in insect cells a 31-kDa protein, corresponding to VP3 was detected, indicating an appropriate posttranslational processing of NS/VP3 polypeptide by NS protease itself. The analysis of the N-terminal amino acid sequence of this protein showed that NS protease may cleave an Ala-Ser bond. A study of the potential for vaccination of yellowtail fry by injection of insect cell lysates infected with baculovirus, containing either cDNA of segment A, VP2-epitope, or NS/VP3 was undertaken. Only a vaccination with cell lysates infected with a recombinant virus carrying the full length of YAV segment A gene demonstrated approximately the same effect as that of inactivated YAV. This result suggested that all proteins VP2, VP3, and NS are required for an effective vaccination.
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86
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Wato S, Kamei K, Arakawa T, Philo JS, Wen J, Hara S, Yamaguchi H. A chimera-like alpha-amylase inhibitor suggesting the evolution of Phaseolus vulgaris alpha-amylase inhibitor. J Biochem 2000; 128:139-44. [PMID: 10876168 DOI: 10.1093/oxfordjournals.jbchem.a022724] [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: 11/14/2022] Open
Abstract
White kidney bean (Phaseolus vulgaris) contains two kinds of alpha-amylase inhibitors, one heat-stable (alpha AI-s) and one heat-labile (alpha AI-u). alpha AI-s has recently been revealed to be a tetrameric complex, alpha(2)beta(2), with two active sites [Kasahara et al. (1996) J. Biochem. 120, 177-183]. The present study was undertaken to reveal the molecular features of alpha AI-u, which is composed of three kinds of subunits, alpha, beta, and gamma. The gamma-subunit, in contrast to the alpha- and beta-subunits that are indistinguishable from the alpha- and beta-subunits of alpha AI-s, was found to correspond to a subunit of an alpha-amylase inhibitor-like protein, which has been identified as an inactive, evolutionary intermediate between arcelin and the alpha-amylase inhibitor in a P. vulgaris defense protein family. The polypeptide molecular weight of alpha AI-u determined by the light-scattering technique, together with the polypeptide molecular weights of the subunits, suggests that alpha AI-u is a trimeric complex, alpha beta gamma. The inhibition of alpha AI-u by increasing amounts of porcine pancreatic alpha-amylase (PPA) indicates that an inactive 1:1 complex is formed between alpha AI-u and PPA. Molecular weight estimation of the complex by the light-scattering technique confirmed that it is a complex of alpha AI-u with one PPA molecule. Thus it seems probable that alpha AI-u is an evolutionary intermediate of the P. vulgaris alpha-amylase inhibitor.
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87
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Tanaka A, Kato M, Hashimoto H, Kamei K, Naruse F, Papagiannopoulos P, Davis MA, Hynes MJ, Kobayashi T, Tsukagoshi N. An Aspergillus oryzae CCAAT-binding protein, AoCP, is involved in the high-level expression of the Taka-amylase A gene. Curr Genet 2000; 37:380-7. [PMID: 10905428 DOI: 10.1007/s002940000125] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Aspergillus oryzae contains a nuclear protein designated AoCP, which binds specifically to a CCAAT sequence in the promoter region of the A. oryzae Taka-amylase A gene. A gene encoding a homologue of Aspergillus nidulans HAPC, a subunit of the A. nidulans CCAAT binding complex, was isolated from A. oryzae and designated AohapC. AoHAPC comprises 215 amino acids and shows 84% identity to A. nidulans HAPC. Transformation of the A. nidulans hapC deletion strain with the AohapC gene restored the CCAAT binding activity, resulting in both enhancement of taa gene expression and complementation for the poor growth phenotype of this strain. Furthermore, introduction of the AohapC gene also restored the expression of the A. nidulans eglA gene, encoding an endo-beta-1,4-glucanase, in the deletion strain. These results indicate functional interchangeability of the genes from two species.
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88
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Hamatani T, Tanabe K, Kamei K, Sakai N, Yamamoto Y, Yoshimura Y. A monoclonal antibody to human SP-10 inhibits in vitro the binding of human sperm to hamster oolemma but not to human Zona pellucida. Biol Reprod 2000; 62:1201-8. [PMID: 10775167 DOI: 10.1095/biolreprod62.5.1201] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
SP-10 is a sperm intra-acrosomal protein, specific to the testis, that is believed to play an important role in egg-sperm binding. While the molecular characterization of the SP-10 protein has been clarified, little is yet known of its functional role in fertilization. We therefore established a monoclonal antibody (mAb pep-SP10) against a peptide (pep-SP10) that included the most hydrophilic portion of human SP-10 between the 135th and 149th amino acids. Human SP-10 was found to be localized in the equatorial region of acrosome-reacted sperm by immunofluorescent staining using our mAb pep-SP10. Monoclonal Ab pep-SP10 inhibited sperm-oolemma binding in the zona-free hamster egg penetration test, but it did not inhibit sperm-zona binding in the hemizona assay. Furthermore, we demonstrated that the oolemmal ligands of human SP-10 did not include beta(1) integrins, the most promising candidates for oocyte ligands involved in sperm-oolemma binding, based on the findings of a human sperm-cultured cell binding assay using F9 mouse embryonal carcinoma cells and F9-transformed cells lacking beta(1) integrins. In conclusion, our present data suggest that human SP-10, expressed on the equatorial region of acrosome-reacted sperm, indeed mediates sperm-oolemma binding in a beta(1) integrin-independent manner, but not sperm-zona binding.
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89
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Yokoi S, Iizasa T, Yoshida S, Kamei K, Hiroshima K, Ohwada O, Fujisawa T. Case report. Localized pulmonary zygomycosis without pre-existing immunocompromised status. Mycoses 2000; 42:675-7. [PMID: 10680447 DOI: 10.1046/j.1439-0507.1999.00507.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pulmonary zygomycosis rarely occurs without pre-existing immunocompromised disease. A 72-year-old male was found to have a nodular shadow (3 cm x 4 cm) in the right S8 and S9 on a chest X-ray. Right lower lobectomy was performed and histological examination of the resected material demonstrated pulmonary zygomycosis. Hyphae stained positively not only with Grocott-Gomori methenamine silver staining, but also with an anti-Rhizopus oryzae polyclonal antibody.
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90
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Arepally GM, Kamei S, Park KS, Kamei K, Li ZQ, Liu W, Siegel DL, Kisiel W, Cines DB, Poncz M. Characterization of a murine monoclonal antibody that mimics heparin-induced thrombocytopenia antibodies. Blood 2000; 95:1533-40. [PMID: 10688805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Antibodies to PF4/heparin can be demonstrated in almost all patients with heparin-induced thrombocytopenia/thrombosis (HIT/HITT) and in some persons exposed to heparin who do not have clinical manifestations. The role of anti-PF4/heparin antibodies in the pathogenesis of HIT/HITT has been difficult to establish because the antibodies found in serum are generally polyclonal and polyspecific. To circumvent this problem, we developed a murine monoclonal antibody (mAb) to human (h) PF4/heparin complexes. A monoclonal IgG(2bkappa )antibody (designated KKO) was identified that bound specifically to hPF4/heparin complexes. Maximal binding of KKO to hPF4/heparin complexes occurred at similar molar ratios of PF4:heparin observed for HIT/HITT antibodies. KKO also bound to hPF4 in association with other glycosaminoglycans. Platelet activation by KKO required heparin and was abrogated by blockade of FcgammaRIIA. In the presence of PF4, KKO bound to endothelial cells, but not to CHO cells lacking heparan sulfate proteoglycans. Variants of PF4 complexed to heparin were recognized equally well by KKO and HIT/HITT sera. KKO competes for binding with a subset of HIT/HITT antibodies that are relatively spared by mutations in the 3rd domain of PF4. The nucleotide and predicted amino acid sequences of KKO and RTO, a murine anti-hPF4 mAb that does not require heparin for binding, revealed no obvious relationship in either the heavy- or the light-chain immunoglobulin variable regions. These studies suggest that KKO recapitulates the antigenic and functional specificity of a subset of HIT/HITT antibodies and may, therefore, provide insight into the pathogenesis of thrombocytopenia and thrombosis in affected persons. (Blood. 2000;95:1533-1540)
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/immunology
- Antigen-Antibody Reactions
- Autoantibodies/chemistry
- Autoantibodies/immunology
- Autoantigens/immunology
- Autoimmune Diseases/chemically induced
- Autoimmune Diseases/immunology
- Binding, Competitive
- CHO Cells
- Cells, Cultured
- Cricetinae
- Cricetulus
- Cross Reactions
- Endothelium, Vascular/immunology
- Enzyme-Linked Immunosorbent Assay
- Epitopes/immunology
- Female
- Genes, Immunoglobulin
- Glycosaminoglycans/immunology
- Heparan Sulfate Proteoglycans/immunology
- Heparin/adverse effects
- Heparin/pharmacology
- Humans
- Immunoglobulin G/chemistry
- Immunoglobulin G/genetics
- Immunoglobulin G/immunology
- Immunoglobulin kappa-Chains/genetics
- Macromolecular Substances
- Mice
- Mice, Inbred BALB C
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Platelet Activation/drug effects
- Platelet Factor 4/genetics
- Platelet Factor 4/immunology
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/immunology
- Sequence Alignment
- Sequence Homology, Amino Acid
- Species Specificity
- Thrombocytopenia/chemically induced
- Thrombocytopenia/immunology
- Thrombophilia/chemically induced
- Thrombophilia/immunology
- Umbilical Veins
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91
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Watanabe T, Kuriyama K, Kamei K. [Case of pulmonary aspergillosis successfully treated with itraconazole]. THE JAPANESE JOURNAL OF ANTIBIOTICS 2000; 53:103-6; discussion 106-7. [PMID: 10896537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
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92
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Miyazaki Y, Sakashita H, Tanaka T, Kamei K, Nishimura K, Yoshizawa Y. Mucoid impaction caused by monokaryotic mycelium of Schizophyllum commune in association with bronchiectasis. Intern Med 2000; 39:160-2. [PMID: 10732837 DOI: 10.2169/internalmedicine.39.160] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 51-year-old female was admitted to our hospital because of fever, cough, and hemoptysis. A chest radiograph showed a partial collapse of the left upper division and infected bullae in the left upper lobe. Bronchoscopic examination showed thick mucous plugs in the left upper bronchus. The isolates of the plugs proved to be Schizophyllum commune. Neither accumulation of eosinophils nor Charcot-Leyden crystals were present in the plugs. Mild ectatic changes of the left upper bronchus had been observed 17 years previously. We describe the first case of mucoid impaction, which was independent of the immunological reactions, caused by S. commune in association with bronchiectasis.
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93
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Kamei K, McCullough MJ, Stevens DA. Initial case of Candida dubliniensis infection from Asia: non-mucosal infection. Med Mycol 2000; 38:81-3. [PMID: 10746232 DOI: 10.1080/mmy.38.1.81.83] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
A yeast, repeatedly isolated from a post-surgical abdominal infection of a 75-year-old Japanese man, was genotyped as Candida dubliniensis. This is the first reported case in Asia of this recently described fungus.
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94
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Kamei K, McCullough MJ, Stevens DA. Initial case of Candida dubliniensis infection from Asia: non-mucosal infection. Med Mycol 2000. [DOI: 10.1080/714030898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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95
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Sato S, Kamei K, Taniguchi M, Sato H, Takano R, Mori H, Ichida M, Hara S. Cloning and expression of the Momordica charantia trypsin inhibitor II gene in silkworm by using a baculovirus vector. Biosci Biotechnol Biochem 2000; 64:393-8. [PMID: 10737198 DOI: 10.1271/bbb.64.393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
MCTI-II (Momordica charantia trypsin inhibitor II) isolated from bitter gourd (Momordica charantia LINN.) seeds is one of the serine protease inhibitors of the squash family. We cloned cDNA that encodes MCTI-II and constructed an expression system for MCTI-II by using a baculovirus vector. The recombinant baculovirus was inoculated to early fifth-instar larvae of the silkworm (strain: Shunrei x Shougetsu). Four days after infection, the hemolymph of silkworm larvae was collected and the recombinant protein was purified. Two kinds of expressed MCTI-II protein were obtained. An amino acid sequence analysis of the two proteins indicates that both were similar to the authentic inhibitor, except for the addition of a tripeptide derived from the vector at the N-terminus. One of the two inhibitors (MCTI-II A) resulted in a single PTH-amino acid in each Edman degradation cycle, while the other (MCTI-II B) resulted in two PTH-amino acids, suggesting the occurrence of cleavage of the reactive site. The inhibitory activities of MCTI-II expressed toward trypsin are examined in terms of the Ki value, these being 6.4 x 10(-10)M for MCTI-II A and 5.2 x 10(-10) M for MCTI-II B.
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96
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Uchiyama G, Asakura T, Hotoku S, Mineo H, Kamei K, Watanabe M, Fujine S. J Radioanal Nucl Chem 2000; 246:683-688. [DOI: 10.1023/a:1006756215590] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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97
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Uchiyama G, Mineo H, Hotoku S, Asakura T, Kamei K, Watanabe M, Nakano Y, Kimura S, Fujine S. PARC process for an advanced PUREX process. PROGRESS IN NUCLEAR ENERGY 2000. [DOI: 10.1016/s0149-1970(00)00040-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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98
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Honda A, Kamei K, Unno H, Hiroshima K, Kuriyama T, Miyaji M. A murine model of zygomycosis by Cunninghamella bertholletiae. Mycopathologia 1999; 144:141-6. [PMID: 10531680 DOI: 10.1023/a:1007095831301] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Infections by Cunninghamella bertholletiae have been on the increase in recent years. However, little is known about this fungus and its infection. To clarify the pathogenicity of C. bertholletiae, we made a murine model, and to our knowledge, the first infectious model of this fungus. ICR mice pretreated with cortisone acetate and cyclophosphamide were inoculated intratracheally with 5 x 10(5) spores of C. bertholletiae. About half of the mice died by day 4 and 90% died by day 9. C. bertholletiae was cultured from the lungs, and the pathological analysis disclosed diffuse hyphal growth in the lungs, resulting in necrosis in the later stage. Angioinvasion with alveolar hemorrhage was extremely pronounced from the early stage, and this was the most characteristic feature of this infection. Treatment with amphotericin B showed only minimal improvement of survival, comparable to the poor result of this treatment in actual human cases. In fact, our model has many similarities to the actual human infection by C. bertholletiae, and will be useful for further investigations of this infection.
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99
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Tanaka Y, Kamei K, Otoguro K, Omura S. Heme-dependent radical generation: possible involvement in antimalarial action of non-peroxide microbial metabolites, nanaomycin A and radicicol. J Antibiot (Tokyo) 1999; 52:880-8. [PMID: 10604757 DOI: 10.7164/antibiotics.52.880] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Antimalarial screening was performed for microbial metabolites that simulate artemisinin in their mode of action, a potent antimalarial component of an herbal remedy with a characteristic peroxide structure. Nanaomycin A was identified in this screen as an antimalarial compound, together with radicicol and several other compounds already reported (J. Antibiotics 51: 153 approximately 160, 1998). Nanaomycin A inhibited in vitro growth of the human malaria parasite Plasmodium falciparum with an IC80 value of 33.1 nM. It was as potent as radicicol and about 1/10 as potent as artemisinin. Studies on the mode of action suggested that the antimalarial action of the two non-peroxides, nanaomycin A and radicicol, involved heme-dependent radical generation, as is for the peroxide artemisinin. Namely, the inhibition of in vitro growth of malaria parasite by nanaomycin A or radicicol was reversed by tocopherol, a radical scavenger added to the assay mixture. Secondly, in a reaction system established for radical detection, in which a test radical donor and beta-alanylhistidine as a radical recipient were incubated with and without hemin, the two compounds caused heme-dependent decreases of beta-alanylhistidine, as did artemisinin. Among the 14 microbial metabolites identified during this screening, a correlation was observed between antimalarial activity and heme-dependent radical generating activity.
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100
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Sato H, Emoto E, Kamata T, Mori H, Kamei K, Kitaoka A, Takano R, Nakajima K, Inui Y, Kudo K, Hara S. Cloning and expression of yellowtail ascites virus segment A. Arch Virol 1999; 144:1405-13. [PMID: 10481746 DOI: 10.1007/s007050050596] [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: 11/24/2022]
Abstract
cDNA of yellowtail ascites virus (YAV) segment A encoding a polyprotein of VP2, NS, and VP3 has been cloned. Comparison of the nucleotide and the deduced amino acid sequences showed very high homology between YAV and other aquatic birnaviruses. The two small open reading frames (VP5) besides the 5' terminus of the VP2 gene were found on segment A of YAV. Proteins encoded by cDNAs from segment A and the serotype-specific epitope region on VP2 were expressed using a baculovirus vector. Western blot analysis confirmed that a polyprotein was expressed and processed into VP2 and VP3 in insect cells infected with the recombinant baculovirus containing the complete polyprotein coding region. In the case of expression in silkworm larvae, only VP3 was detected in hemocytes and fat body of silkworm larvae infected with the recombinant virus. The recombinant fusion protein consisting of VP2 epitope region and polyhedrin was expressed in insect cells and cross-reacted with a mouse monoclonal antibody against VP2 which had a neutralizing activity to YAV.
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