Ishikawa H

References (14)

Title : Greater responsiveness to donepezil in Alzheimer patients with higher levels of acetylcholinesterase based on attention task scores and a donepezil PET study - Kasuya_2012_Alzheimer.Dis.Assoc.Disord_26_113
Author(s) : Kasuya M , Meguro K , Okamura N , Funaki Y , Ishikawa H , Tanaka N , Iwata R , Yanai K
Ref : Alzheimer Disease & Associated Disorders , 26 :113 , 2012
Abstract : The aim of the study was to predict donepezil responders among patients with Alzheimer disease (AD) based on cognitive tests and positron emission tomography. The Mini-Mental State Examination, Digit Symbol subtest (DigSm) of Wechsler Adult Intelligence Scale Revised, and Trail-Making Test A were administered for 80 patients with AD to assess global function, attention, and executive function, respectively. The same tests and the Clinical Global Impression (CGI) scale were conducted after treatment with oral donepezil (5 mg/d) for 6 months (study 1). [C]-Donepezil positron emission tomography examinations were conducted before and after treatment for 30 randomly selected patients. The distribution volume (DV), which indicates the density of donepezil-binding sites, was calculated using Logan graphical analysis (study 2). In study 1, 35 patients were identified as responders based on the CGI and Mini-Mental State Examination changes. These patients had higher baseline DigSm scores compared with nonresponders. In study 2, 15 patients were responders. DigSm correlated with DV at baseline. DV at baseline and %DV change in responders were higher than in nonresponders, and these variables correlated with DeltaDigSm and CGI scores. Higher baseline attention may predict responsiveness to donepezil in patients with AD, and higher acetylcholinesterase levels result in a greater clinical effect.
ESTHER : Kasuya_2012_Alzheimer.Dis.Assoc.Disord_26_113
PubMedSearch : Kasuya_2012_Alzheimer.Dis.Assoc.Disord_26_113
PubMedID: 21666432

Title : One-pot high-yielding synthesis of the DPP4-selective inhibitor ABT-341 by a four-component coupling mediated by a diphenylprolinol silyl ether -
Author(s) : Ishikawa H , Honma M , Hayashi Y
Ref : Angew Chem Int Ed Engl , 50 :2824 , 2011
PubMedID: 21387497

Title : In vivo visualization of donepezil binding in the brain of patients with Alzheimer's disease - Okamura_2008_Br.J.Clin.Pharmacol_65_472
Author(s) : Okamura N , Funaki Y , Tashiro M , Kato M , Ishikawa Y , Maruyama M , Ishikawa H , Meguro K , Iwata R , Yanai K
Ref : British Journal of Clinical Pharmacology , 65 :472 , 2008
Abstract : WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * Deficit in central cholinergic neurotransmission is a consistent change associated with Alzheimer's disease (AD). * Donepezil hydrochloride exhibits selective inhibition of acetylcholinesterase (AChE) and is widely used for the treatment of AD. * The biodistribution of donepezil in the brain after administration is not precisely understood in vivo. * There is no method to measure the amount of binding of orally administered donepezil to AChE. WHAT THIS STUDY ADDS: * This study clearly visualizes the distribution of donepezil in human brain using [(11)C]-donepezil and positron emission tomography. * This study demonstrates prominent reduction of the donepezil binding site in the AD brain. * This study provides methodology to measure the AChE binding occupancy of orally administered donepezil and provides a new surrogate marker for evaluation and prediction of response to donepezil treatment. AIMS: The aims of this study were to visualize in vivo binding of donepezil to acetylcholinesterase (AChE) in the brain and to establish a method for measuring the amount of binding of orally administered donepezil.
METHODS: [5-(11)C-methoxy]-donepezil ([(11)C]-donepezil) was radiolabelled as a positron emission tomography (PET) tracer. The biodistribution of [(11)C]-donepezil was measured by PET in 10 AD patients and six elderly normal subjects. Two AD patients underwent additional PET measurements after oral administration of donepezil for 6 months.
RESULTS: [(11)C]-donepezil-PET images demonstrated high densities of tracer distribution in AChE-rich brain regions such as the striatum, thalamus, and cerebellum. Compared with elderly normal subjects, patients with mild AD exhibited about 18-20% reduction of donepezil binding in the neocortex and hippocampus, while patients with moderate AD exhibited about 24-30% reduction of donepezil binding throughout the brain. Orally administered donepezil (5 mg day(-1)) induced 61.6-63.3% reduction of donepezil binding in AD brains. The distribution volume of [(11)C]-donepezil in the hippocampus was significantly correlated with MMSE scores in AD patients.
CONCLUSIONS: [(11)C]-donepezil-PET enables quantitative measurement of donepezil binding in the brain. AD patients exhibited reduction of donepezil binding in the brain, even in the early stage of disease. Longitudinal evaluation by this technique enables determination of AChE binding occupancy of orally administered donepezil.
ESTHER : Okamura_2008_Br.J.Clin.Pharmacol_65_472
PubMedSearch : Okamura_2008_Br.J.Clin.Pharmacol_65_472
PubMedID: 18070217

Title : Cloning and expression of gene, and activation of an organic solvent-stable lipase from Pseudomonas aeruginosa LST-03 - Ogino_2007_Extremophiles_11_809
Author(s) : Ogino H , Katou Y , Akagi R , Mimitsuka T , Hiroshima S , Gemba Y , Doukyu N , Yasuda M , Ishimi K , Ishikawa H
Ref : Extremophiles , 11 :809 , 2007
Abstract : Organic solvent-tolerant Pseudomonas aeruginosa LST-03 secretes an organic solvent-stable lipase, LST-03 lipase. The gene of the LST-03 lipase (Lip9) and the gene of the lipase-specific foldase (Lif9) were cloned and expressed in Escherichia coli. In the cloned 2.6 kbps DNA fragment, two open reading frames, Lip9 consisting of 933 nucleotides which encoded 311 amino acids and Lif9 consisting of 1,020 nucleotides which encoded 340 amino acids, were found. The overexpression of the lipase gene (lip9) was achieved when T7 promoter was used and the signal peptide of the lipase was deleted. The expressed amount of the lipase was greatly increased and overexpressed lipase formed inclusion body in E. coli cell. The collected inclusion body of the lipase from the cell was easily solubilized by urea and activated by using lipase-specific foldase of which 52 or 58 amino acids of N-terminal were deleted. Especially, the N-terminal methionine of the lipase of which the signal peptide was deleted was released in E. coli and the amino acid sequence was in agreement with that of the originally-produced lipase by P. aeruginosa LST-03. Furthermore, the overexpressed and solubilized lipase of which the signal peptide was deleted was more effectively activated by lipase-specific foldase.
ESTHER : Ogino_2007_Extremophiles_11_809
PubMedSearch : Ogino_2007_Extremophiles_11_809
PubMedID: 17657406
Gene_locus related to this paper: pseae-llipa

Title : Teratogenicity and developmental toxicity of chlorpyrifos. Maternal exposure during organogenesis in mice - Tian_2005_Reprod.Toxicol_20_267
Author(s) : Tian Y , Ishikawa H , Yamaguchi T , Yamauchi T , Yokoyama K
Ref : Reprod Toxicol , 20 :267 , 2005
Abstract : Chlorpyrifos, an organophosphate pesticide, was evaluated for potential teratogenicity and developmental toxicity in mice. Pregnant females were given a single intraperitoneal injection (40 or 80 mg/kg) on day 10 of gestation and fetuses were evaluated on gestation day 17. At 80 mg/kg, chlorpyrifos treatment resulted in a significant reduction in numbers of live fetuses, and increase in resorptions, versus control litters. There was no indication of maternal toxicity. External and skeletal malformations were observed at 80 mg/kg, but not 40 mg/kg. Rates of fetuses with cleft palate increased significantly (p<0.05) following 80 mg/kg chlorpyrifos (5.97%) versus control litters (0.97%). Similarly, the absence of thoracic vertebrae was increased and the number of caudal vertebrae was significantly decreased. It is suggested that chlorpyrifos is teratogenic and embryotoxic in mice at doses below those that cause significant maternal toxicity.
ESTHER : Tian_2005_Reprod.Toxicol_20_267
PubMedSearch : Tian_2005_Reprod.Toxicol_20_267
PubMedID: 15907662

Title : Cloning, expression, and characterization of a lipolytic enzyme gene (lip8) from Pseudomonas aeruginosa LST-03 - Ogino_2004_J.Mol.Microbiol.Biotechnol_7_212
Author(s) : Ogino H , Mimitsuka T , Muto T , Matsumura M , Yasuda M , Ishimi K , Ishikawa H
Ref : J Molecular Microbiology Biotechnol , 7 :212 , 2004
Abstract : A lipolytic enzyme gene (lip8) was cloned from organic solvent-tolerant Pseudomonas aeruginosa LST-03 and sequenced. In the sequenced nucleotides, an open reading frame consisting of 1,173 nucleotides and encoding 391 amino acids was found. Lip8 is considered to belong to the family VIII of lipolytic enzymes whose serine in the consensus sequence of -Ser-Xaa-Xaa-Lys- acts as catalytic nucleophile. The gene was expressed in Escherichia coli and purified by a combination of ammonium sulfate fractionation and hydrophobic interaction and ion-exchange chromatographies to homogeneity on SDS-PAGE analysis. The optimum temperature and heat stability of Lip8 were not as high as those of Lip3 and LST-03 lipase, two other lipolytic enzymes from the same strain. Addition of glycerol to a solution containing Lip8 stabilized this enzyme. By measuring the activities against various triacylglycerols and fatty acid methyl esters having carbon chains of different lengths, Lip8 was categorized as an esterase which has higher activities against fatty acid methyl esters with short-chain fatty acids.
ESTHER : Ogino_2004_J.Mol.Microbiol.Biotechnol_7_212
PubMedSearch : Ogino_2004_J.Mol.Microbiol.Biotechnol_7_212
PubMedID: 15383719

Title : Cloning, expression and characterization of a lipase gene (lip3) from Pseudomonas aeruginosa LST-03 - Ogino_2004_Mol.Genet.Genomics_271_189
Author(s) : Ogino H , Hiroshima S , Hirose S , Yasuda M , Ishimi K , Ishikawa H
Ref : Mol Genet Genomics , 271 :189 , 2004
Abstract : A lipase gene (lip3) was cloned from the Pseudomonas aeruginosa strain LST-03 (which tolerates organic solvents) and expressed in Escherichia coli. The cloned sequence includes an ORF consisting of 945 nucleotides, encoding a protein of 315 amino acids (Lip3 lipase, 34.8 kDa). The predicted Lip3 lipase belongs to the class of serine hydrolases; the catalytic triad consists of the residues Ser-137, Asp-258, and His-286. The gene cloned in the present study does not encode the LST-03 lipase, a previously isolated solvent-stable lipase secreted by P. aeruginosa LST-03, because the N-terminal amino acid sequence of the Lip3 lipase differs from that of the LST-03 lipase. Although the effects of pH on the activity and stability of the Lip3 lipase, and the temperature optimum of the enzyme, were similar to those of the LST-03 lipase, the relative activity of the Lip3 lipase at lower temperatures (0-35 degrees C) was higher than that of the LST-03 lipase. In the absence of organic solvents, the half-life of the Lip3 lipase was similar to that of the LST-03 lipase. However, in the presence of most of the organic solvents tested in this study (the exceptions were ethylene glycol and glycerol), the stability of the Lip3 lipase was lower than that of the LST-03 lipase.
ESTHER : Ogino_2004_Mol.Genet.Genomics_271_189
PubMedSearch : Ogino_2004_Mol.Genet.Genomics_271_189
PubMedID: 14740297
Gene_locus related to this paper: pseae-PA2949

Title : A cDNA resource from the basal chordate Ciona intestinalis -
Author(s) : Satou Y , Yamada L , Mochizuki Y , Takatori N , Kawashima T , Sasaki A , Hamaguchi M , Awazu S , Yagi K , Sasakura Y , Nakayama A , Ishikawa H , Inaba K , Satoh N
Ref : Genesis , 33 :153 , 2002
PubMedID: 12203911
Gene_locus related to this paper: cioin-141645 , cioin-147959 , cioin-150181 , cioin-154370 , cioin-ACHE1 , cioin-ACHE2 , cioin-cxest , cioin-F6V269

Title : Lipase production in two-step fed-batch culture of organic solvent-tolerant Pseudomonas aeruginosa LST-03 - Ito_2001_J.Biosci.Bioeng_91_245
Author(s) : Ito T , Kikuta H , Nagamori E , Honda H , Ogino H , Ishikawa H , Kobayashi T
Ref : J Biosci Bioeng , 91 :245 , 2001
Abstract : Efficient lipase production by two-step fed-batch culture of an organic solvent-tolerant bacterium, Pseudomonas aeruginosa LST-03, was investigated. When FB synthetic medium was used in flask culture, no lipase activity was detected, whereas lipase was produced at 2.3 I.U./ml in C2 complex medium. However, lipase production was induced in FB medium when a fatty acid was added to the culture broth in the stationary phase. Among fatty acids tested, long chain saturated fatty acids, such as C18 (stearic acid) and C20 (arachidic acid), were found to function as effective inducers for the production of lipase, giving an activity level almost the same as that obtained in C2 medium in flask culture. Two-step lipase production, comprised of a growth phase in fed-batch mode and a production phase in which lipase was induced by the addition of 5% (v/v) stearic acid, was carried out in a jar-fermentor. In the growth phase, the maximum cell concentration at 16 h was only 20 in terms of the optical density at 660 nm (OD660), and a low level of lipase production (8 I.U./ml) was obtained after 167 h. This was considered to be due to the exhaustion of several medium components brought about by the use of an unsuitable medium or feeding solution. After analyzing the contents of the compounds in the culture broth by inductively coupled plasma spectrometry for metal ions and HPLC for anions, a modified FB medium was designed. When this modified FB medium was used in two-step fed-batch culture, the maximum cell concentration reached an OD660 of 55 (30.2 g-dry cells/l) at 16.5 h, and lipase was produced at 96 I.U./ml after 35 h, which is approximately 40 times higher than the production level obtained in flask culture using C2 medium.
ESTHER : Ito_2001_J.Biosci.Bioeng_91_245
PubMedSearch : Ito_2001_J.Biosci.Bioeng_91_245
PubMedID: 16232983

Title : Genome sequence of the endocellular bacterial symbiont of aphids Buchnera sp. APS - Shigenobu_2000_Nature_407_81
Author(s) : Shigenobu S , Watanabe H , Hattori M , Sakaki Y , Ishikawa H
Ref : Nature , 407 :81 , 2000
Abstract : Almost all aphid species (Homoptera, Insecta) have 60-80 huge cells called bacteriocytes, within which are round-shaped bacteria that are designated Buchnera. These bacteria are maternally transmitted to eggs and embryos through host generations, and the mutualism between the host and the bacteria is so obligate that neither can reproduce independently. Buchnera is a close relative of Escherichia coli, but it contains more than 100 genomic copies per cell, and its genome size is only a seventh of that of E. coli. Here we report the complete genome sequence of Buchnera sp. strain APS, which is composed of one 640,681-base-pair chromosome and two small plasmids. There are genes for the biosyntheses of amino acids essential for the hosts in the genome, but those for non-essential amino acids are missing, indicating complementarity and syntrophy between the host and the symbiont. In addition, Buchnera lacks genes for the biosynthesis of cell-surface components, including lipopolysaccharides and phospholipids, regulator genes and genes involved in defence of the cell. These results indicate that Buchnera is completely symbiotic and viable only in its limited niche, the bacteriocyte.
ESTHER : Shigenobu_2000_Nature_407_81
PubMedSearch : Shigenobu_2000_Nature_407_81
PubMedID: 10993077

Title : Purification and characterization of organic solvent-stable lipase from organic solvent-tolerant Pseudomonas aeruginosa LST-03 - Ogino_2000_J.Biosci.Bioeng_89_451
Author(s) : Ogino H , Nakagawa S , Shinya K , Muto T , Fujimura N , Yasuda M , Ishikawa H
Ref : J Biosci Bioeng , 89 :451 , 2000
Abstract : An organic solvent-stable lipase (LST-03 lipase) secreted into the culture broth of the organic solvent-tolerant Pseudomonas aeruginosa LST-03 was purified by ion-exchange and hydrophobic interaction chromatography in the presence of 2-propanol. The purified enzyme was homogeneous as determined by SDS-PAGE. The molecular mass of the lipase was estimated to be 27.1 kDa by SDS-PAGE and 36 kDa by gel filtration. The optimum pH and temperature were 6.0 and 37 degrees C. LST-03 lipase was stable at pH 5-8 and below 40 degrees C. Its hydrolytic activity was highest against tricaproin (C6), methyl octanoate (C8), and coconut oil respectively among the triacylglycerols, fatty acid methyl esters, and natural oils investigated. The enzyme cleaved not only the 1,3-positioned ester bonds, but also the 2-positioned ester bond of triolein. It exhibited high levels of activity in the presence of n-decane, n-octane, DMSO, and DMF as well as in the absence of an organic solvent. In addition, LST-03 lipase was stabler in the presence of n-decane, ethyleneglycol, DMSO, n-octane, n-heptane, isooctane, and cyclohexane than in the absence of an organic solvent.
ESTHER : Ogino_2000_J.Biosci.Bioeng_89_451
PubMedSearch : Ogino_2000_J.Biosci.Bioeng_89_451
PubMedID: 16232776

Title : Effect of additives on transesterification activity of Rhizopus chinensis lipase - Yasuda_2000_J.Biosci.Bioeng_90_681
Author(s) : Yasuda M , Kiguchi T , Kasahara H , Ogino H , Ishikawa H
Ref : J Biosci Bioeng , 90 :681 , 2000
Abstract : The transesterification activity of powder lipase prepared from the purified lipase of Rhizopus chinensis cells by freeze-drying was quite low compared with that of acetone-dried cells. Additives which could enhance the transesterification activity of the freeze-dried powder lipase were screened. The freeze-dried lipases prepared with certain fatty acid methylesters or certain types of surfactants exhibited high transesterification activity. It was shown that not only the solubility of the freeze-dried lipase in n-hexane but also the organic solvent-stability was enhanced when methyl stearate was added to the lipase solution at the freeze-drying step.
ESTHER : Yasuda_2000_J.Biosci.Bioeng_90_681
PubMedSearch : Yasuda_2000_J.Biosci.Bioeng_90_681
PubMedID: 16232933

Title : Purification and characterization of lipase from Rhizopus chinensis cells - Yasuda_1999_J.Biosci.Bioeng_88_571
Author(s) : Yasuda M , Ogino H , Kiguchi T , Kotani T , Takakura S , Ishibashi T , Nakashima T , Fukuda H , Ishikawa H
Ref : J Biosci Bioeng , 88 :571 , 1999
Abstract : Lipase from Rhizopus chinensis cells was purified and characterized. The molecular mass of purified lipase was 28.4 kDa and the optimal temperature and pH for its activity were 37 degrees C and 5.5, respectively. Purified lipase exhibited high hydrolytic activity against fatty acid methyl esters such as methyl caprylate, methyl laurate, and methyl palmitate. Freeze-dried lipase catalyzed the transesterification between olive oil and methyl laurate in n-hexane.
ESTHER : Yasuda_1999_J.Biosci.Bioeng_88_571
PubMedSearch : Yasuda_1999_J.Biosci.Bioeng_88_571
PubMedID: 16232664

Title : Radioimmunoassay for acetylcholine in the rat brain - Kawashima_1980_J.Pharmacol.Methods_3_115
Author(s) : Kawashima K , Ishikawa H , Mochizuki M
Ref : J Pharmacol Methods , 3 :115 , 1980
Abstract : Specific antiserum against acetylcholine (ACh) was produced in the rabbit immunized with a choline hemiglutarate-bovine serum albumin conjugate. The antiserum significantly cross-reacted with choline carboxylates, such as butyrylcholine, succinylcholine, and carbamylcholine. However, neither choline itself nor choline phosphates, such as phosphatidylcholine and phosphorylcholine, showed any significant cross-reaction. The antiserum was used to develop a radioimmunoassay for ACh. The assay can reliably determine as little as 170 pg of ACh. Acetylcholine concentrations in two regions of the rat brain were determined directly from an aqueous extract. After inhibition of acetylcholinesterase with physostigmine, ACh increased more in the forebrain than in the brainstem.
ESTHER : Kawashima_1980_J.Pharmacol.Methods_3_115
PubMedSearch : Kawashima_1980_J.Pharmacol.Methods_3_115
PubMedID: 7392652