225 results match your criteria: "Tokyo University of Fisheries.[Affiliation]"

A recent revival in using cephalopods as experimental animals has rekindled interest in their biology and life cycles, information with direct applications also in the rapidly growing ornamental aquarium species trade and in commercial aquaculture production for human consumption. Cephalopods have high rates of growth and food conversion, which for aquaculture translates into short culture cycles, high ratios of production to biomass and high cost-effectiveness. However, at present, only small-scale culture is possible and only for a few species: the cuttlefish Sepia officinalis, the loliginid squid Sepioteuthis lessoniana and the octopuses Octopus maya and O.

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The physical habitat characteristics associated with spatial distribution patterns of the freshwater mussel Pronodularia japanensis, which is used for oviposition by the Tokyo bitterling Tanakia tanago, were investigated in a small stream within a Tokyo bitterling protected area. The distribution of the mussels was found to be in an under-dispersed, non-random spatial pattern. Mussel occurrence correlated negatively with sediment softness, and positively with flow velocity, while mussel abundance was associated negatively with sediment softness and positively with sediment type (particle size).

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A CC chemokine gene (JFCCL3) was cloned and sequenced from Japanese flounder, Paralichthys olivaceus. The JFCCL3 cDNA contains an open reading frame of 288 nucleotides encoding 95 amino acid residues. The predicted amino acid sequence of JFCCL3 showed the conserved cysteine of the beta chemokine plus two additional cysteines.

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The mode of action of an extracellular -1,3-glucanase from Bacillus clausii NM-1 on beta-1,3-3glucooligosaccharides and their alditols was studied. The enzyme could not hydrolyze laminaribiose or laminaritriose. beta-1,3-Glucooligosaccharides higher than laminarihexaose were rapidly hydrolyzed, while laminaritetraose was slowly hydrolyzed.

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We prepared a beta-1,3-glucan oligomer (DP> or = 4) from laminarin (DP: 25-30) derived from Laminaria digitata with beta-1,3-glucanase, and examined its effect on human peripheral blood monocytes. Conditioned medium prepared by incubating monocytes (MC-CM) with the beta-1,3-glucan oligomer showed strong inhibitory activity against the proliferation of human leukemic U937 cells. Since the beta-1,3-glucan oligomer had no direct cytotoxic effect on U937 cells up to 1000 microg/ml, the cytotoxicity of the MC-CM may be due to cytotoxic cytokines produced from monocytes stimulated by the beta-1,3-glucan oligomer.

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A novel extracellular alkaline stable beta-1,3-glucanase produced by Bacillus clausii NM-1 isolated from the ezo abalone Haliotis discus hannai was purified by ammonium sulfate precipitation, DEAE-Sepharose FF ion exchange chromatography and Sephacryl S-200HR gel filtration. The molecular weight of the purified enzyme was estimated to be 71 kDa from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was very stable at pH 5.

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This study reports on the optimization of the culture conditions for a thermotolerant eukaryotic algal strain, Prototheca zopfii RND16, which can effectively degrade and assimilate n-alkanes at elevated temperatures. RND16 was able to grow on 1% (v/v) n-alkanes (C14-C17) at temperatures up to 38 degrees C. This ability differs from a previous finding that P.

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Effect of osmotic stabilizers on protoplast generation of Chlorella ellipsoidea yellow/white color mutants.

J Biosci Bioeng

November 2005

Laboratory of Marine Biochemistry, Tokyo University of Fisheries, Konan, Minato, Tokyo 108-8477, Japan.

The effect of osmotic stabilizers on protoplast formation of yellow/white color mutants of Chlorella ellipsoidea was studied. The UF-1 strain, one of the mutants, had the same growth rate as the parent C. ellipsoidea at 4.

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Seven new meroditerpenoids, strongylophorines 13-19 (1-7), have been isolated together with the four known strongylophorines 2 (8), 3 (9), 4 (10), and 8 (11) by a screening method using oocytes of the starfish Asterina pectinifera from a marine sponge Strongylophora strongylata collected at Iriomote Island, Okinawa, Japan. The structures were assigned according to their spectral data. Ten strongylophorines inhibited the maturation of starfish oocytes in the range 1.

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Recent topics in NMR imaging and MRI.

Magn Reson Med Sci

September 2005

Department of Food Science and technology, Tokyo University of Fisheries, Japan.

NMR and NMR imaging (MRI) are finding increasing use not only in the clinical and medical fields, but also in material, physicochemical, biological, geological, industrial and environmental applications. This short review is limited to two topics: (i) new techniques and pulse sequences and their application to non-clinical fields that may have clinical application; and (ii) new trends in MR contrast agents. The former topic addresses pulse sequence and data analysis; dynamics such as diffusion, flow, velocity and velocimetry; chemometrics; pharmacological agents; and chemotherapy; the latter topic addresses contrast agents (CA) sensitive to biochemical activity; CA based on water exchange; molecular interactions and stability of CA; characteristics of emerging CA; superparamagnetic CA; and macromolecular CA.

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Agmatine (Agm) is an indicator of squid freshness. The Agm sensor was developed using flow injection analysis (FIA) that consisted of the putrescine oxidase (PuOx) reactor, the agmatinase (AUH)-PuOx reactor and two oxygen electrodes. In the proposed sensor, the first step is that coexisting cadaverine (Cad) and putrescine (Put) are removed by passing through the PuOx reactor and the initial decomposition is determined by the amount of oxygen consumed, simultaneously.

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To identify the pubertal development of the brain-pituitary-gonad (BPG) axis in female red seabream (Pagrus major), we investigated the effects of gonadotropin-releasing hormone agonist (GnRHa) on seabream (sb) GnRH mRNA levels in the brain, gonadotropin subunit mRNA levels in the pituitary, and serum concentrations of luteinizing hormone (LH), testosterone (T) and estradiol-17beta (E2) in pre-pubertal fish. Sexually immature 12-month-old fish were implanted with a cholesterol pellet containing GnRHa and maintained for 10-20 days. In the brain, GnRHa had no effect on sbGnRH mRNA levels.

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The binding effect of divalent cation Cu(2+) on the gelation process with a coil-helix transition in Cu(2+)/gellan aqueous solutions has been successfully elucidated by EPR, CD, and viscoelasticity measurements. Generally, Na-type gellan gum in aqueous solution can make gel when accompanied by an intrinsic coil-helix formation induced by hydrogen bonding between chains without any additional cations at T(ch)(-)(in) ( approximately 29 degrees C) with cooling temperature. An extrinsic coil-helix transition, induced by additional divalent cations in advance of the intrinsic sol-gel transition of gellan gum, is separately detected by CD measurement.

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Pyocyanin is the blue phenazine pigment produced by Pseudomonas aeruginosa. Pyocyanin production using immobilized cells was investigated. The maximum production of pyocyanin was obtained using cells immobilized in kappa-carrageenan.

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Gene knock-down technology using antisense molecules has many applications for studying gene function, disrupting undesirable genetic traits, as well as providing effective therapy for a number of viral diseases. Encouraged by these applications, we developed a gene knock-down technique to interfere with gene expression using transgenic rainbow trout expressing the green fluorescent protein (GFP) gene as a model. One of the antisense morpholino phosphorodiamidate oligonucleotides (AMOs) used in this study (AtGFP-1) was 25 nucleotides in length and localized against codons 2 to 8 of GFP messenger RNA.

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Several yeasts were isolated from a drainage canal in a Japanese fish food processing factory. They were characterized by the decomposition of organic polymers such as proteins and reducing sugars, their growth in the wastewater, the decrease in total organic carbon (TOC), and taxonomy. Three strains of yeast dominated the sample: Debaryomyces occidentalis (P1), Trichosporon ovoides (P19), and a strain that could not be identified (S27).

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Genomic bacterial artificial chromosome library of the Japanese flounder Paralichthys olivaceus.

Mar Biotechnol (NY)

November 2000

Laboratory of Genetics and Biochemistry, Tokyo University of Fisheries, Konan 4-5-7, Minato-ku, Tokyo 108-8477, Japan.

We have constructed a genomic bacterial artificial chromosome (BAC) library from homozygous cloned Japanese flounder Paralichthys olivaceus using the pBAC- lac vector. This BAC library consists of about 49,100 clones and is deposited in 128 microtiter plates with 384 wells. The average size of inserted DNA was calculated to be 165 kb.

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Amperometric determination of laminarin using immobilized beta-1,3-glucanase.

Biosens Bioelectron

January 2004

Department of Food Science and Technology, Tokyo University of Fisheries, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan.

A novel sensor system equipped with a reactor packed with beads containing immobilized beta-1,3-glucanase and glucose oxidase was developed for the amperometric determination of laminarin concentration. The proposed sensor system consisted of a reactor, an oxygen electrode, a flow cell, a pump, a buffer tank, and a recorder. The measurement was performed with a flow injection system.

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This study was designed to examine the effects of dietary vitamin E (VE) on modulation of immune responses when supplied with two levels of n-3 highly unsaturated fatty acids (n-3 HUFA) in rainbow trout, Oncorhynchus mykiss. Six semipurified diets were prepared containing three levels of dietary VE (0, 100 or 1000 mg alpha-tocopheryl acetate kg(-1) diet) and n-3 HUFA either at 20 or 48% of dietary lipid provided from fish oil or docosahexaenoic acid (DHA) concentrated fish oil respectively. The diets were fed to rainbow trout (100 g initial mean weight) for 15 weeks.

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Lactic acid bacteria from "terasi" shrimp paste, a highly popular fermented seafood in Indonesia were isolated and characterized. Viable cell counts were 10(4) to 10(6) cfu/g on MRS medium. All the isolates were catalase-negative, gram-positive cocci and were able to grow at 15% NaCl.

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A marine bacterium producing protease inhibitors was isolated from neritic sea water and was studied phenotypically, genotypically and phylogenetically. This bacterium (strain B-10-31(T)) produced three types of protease inhibitor, namely, marinostatin, monastatin and leupeptin, which were considerably different in terms of their chemical structure and properties. Strain B-10-31(T) was a rod-shaped, non-spore-forming, Gram-negative, strictly aerobic bacterium that was motile by means of one polar flagellum.

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A highly pure and viable primordial germ cell (PGC) population appears to be an essential tool for establishing a cell line that can differentiate into a germ cell lineage and for studying the molecular biology and biochemistry of fish PGCs. Therefore, the aim of the present study was to establish a flow cytometric method for isolating highly pure and viable PGCs. As the material for PGC isolation, we used transgenic rainbow trout possessing the green fluorescent protein (GFP) gene driven by trout vasa-gene regulatory sequences (pvasa-GFP).

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An epidermal growth factor (EGF)-like toxin (gigantoxin I) and two sodium channel toxins (gigantoxins II and III), previously isolated from the sea anemone Stichodactyla gigantea, were cloned for their cDNAs. The precursor protein of gigantoxin I is composed of a signal peptide, propart and mature peptide, similar to those of gigantoxins II and III, and is much simpler in structure than those of mammalian EGFs. In addition, gigantoxin I as well as gigantoxins II and III was demonstrated to be contained in nematocysts, suggesting that gigantoxin I functions as a toxin in S.

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A marine bacterium Ruegeria atlantica (designated as strain TUF-D) was isolated from a glass plate submerged in the coastal water. Three new chlorine containing compounds (1 to approximately 3), together with penicillic acid (4) were obtained from a marine-derived fungus Aspergillus ostianus strain TUF 01F313 isolated from a marine sponge at Pohnpei as antibacterial components against R. atlantica.

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A D-alanine (D-Ala) sensor for the monitoring of a fermentation process was developed using flow injection analysis (FIA). The FIA system consisted of a D-amino acid oxidase (D-AAOx) reactor, a Pyruvate oxidase (PyOx) electrode and a contrast electrode in the flow cell, and through the oxidation of D-amino acids in the D-AAOx reactor, pyruvic acid was formed only from D-Ala. The pyruvic acid was further oxidized with PyOx via the D-AAOx reaction.

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