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T Taniguchi

Publications and source records attributed to T Taniguchi.

At least 19 recordsLinked to original sources
PubMed2006

Keyword extraction, ranking, and organization for the neuroinformatics platform.

Brain-related researches encompass many fields of studies and usually involve worldwide collaborations. Recognizing the value of these international collaborations for efficient use of resources and improving the quality of brain research, the International Neuroinformatics Coordinating Facility (INCF) started to coordinate the effort of establishing neuroinformatics (NI) centers and portal sites among the different participating countries. These NI centers and portal sites will serve as the conduit for the interchange of information and brain-related resources among different countries. In Japan, several NI platforms under the support of NIJC (NI Japan Center) are being developed with one platform called, Visiome, already operating and publicly accessible at "http://www.platform.visiome.org". Each of these platforms requires their own set of keywords that represent important terms covering their respective fields of study. One important function of this predefined keyword list is to help contributors classify the contents of their contributions and group related resources. It is vital, therefore, that this predefined list should be properly chosen to cover the necessary areas. Currently, the process of identifying these appropriate keywords relies on the availability of human experts which does not scale well considering that different areas are rapidly evolving. This problem prompted us to develop a tool to automatically filter the most likely terms preferred by human experts. We tested the effectiveness of the proposed approach using the abstracts of the Vision Research Journal (VR) and Investigative Ophthalmology and Visual Science Journal (IOVS) as source files.

Animals↗
PubMed2006

Finasteride 1 mg has no inhibitory effect on omeprazole metabolism in extensive and poor metabolizers for CYP2C19 in Japanese.

OBJECTIVE: To examine the inhibitory effect of finasteride 1 mg on the metabolism of omeprazole in genetically determined extensive (EMs) and poor metabolizers (PMs) for CYP2C19 in young healthy Japanese male subjects. METHODS: Twenty-four volunteers participated in this study, among whom 12 were homozygous EMs and 12 were PMs for CYP2C19. A single center, controlled, randomized, open, crossover study with a 5 day washout between the two study periods was performed. Each of the six EMs and PMs received a single oral 20 mg dose of omeprazole on day 1 (treatment I). After a 5 day washout period, these subjects received 1 mg of finasteride once a day for three consecutive days, and a single oral 20 mg dose of omeprazole was co-administered on day 3 (treatment II). The 12 other EMs and PMs received treatments I and II in reverse. Plasma samples were collected for up to a 12 hours postdose of omeprazole, and the pharmacokinetic parameters of omeprazole were determined. RESULTS: The geometric mean ratio (GMR) for the AUC((0-12 hr)) of omeprazole when co-administered with finasteride/omeprazole alone is 1.13 (90%CI, 1.03, 1.25) and 0.96 (0.88, 1.05) in EMs and PMs, respectively. Finasteride did not significantly alter C(max), T(max) and t(1/2) in both genotypes. CONCLUSION: Finasteride 1 mg, widely used for the treatment of androgenetic alopecia in men, did not meaningfully increase omeprazole exposure (20 mg) in both EMs and PMs for CYP2C19. These results indicate that finasteride does not meaningfully inhibit CYP2C19 activity in vivo at the dose of 1 mg.

Adult↗
PubMed2006

Transient appearance of hepatic natural killer cells with high cytotoxicity and unique phenotype in very young mice.

There were few natural killer (NK) cells in the liver in very young mice at the age of 1-2 weeks. This was because the cell yield from the liver of young mice was low. The percentage of NK cells in the liver of young mice, however, was almost comparable with that in the liver of adult mice. Lymphocytes were isolated from the liver and spleen of C57BL/6 (B6) mice, and NK cytotoxicity and phenotype were herein examined in this study. NK cytotoxicity was extremely high in the liver of very young mice. This phenomenon was seen in the liver of various normal mouse strains. In contrast, the appearance of high cytotoxicity was not seen in NK cells of the spleen, irrespective of mouse strains. The quality of NK cells in the liver of young mice was different from that in adult mice. NK cells in the liver of young mice were mainly CD69(+)Mac-1(-) Fas ligand(+), whereas those in the liver of adult mice were CD69(-)Mac-1(+) Fas ligand(-). These results revealed that the quality of hepatic NK cells changes in the process of ageing. Namely, liver NK cells in very young mice temporarily show the highest NK cytotoxicity and a unique activated phenotype. Physiological meaning of the present phenomenon was discussed.

Age Factors↗
PubMed2006

Comparison of MR images and histochemical localization of intra-arterially administered microglia surrounding beta-amyloid deposits in the rat brain.

The therapeutic use of microglial cells has recently received some attention for the treatment of Alzheimer disease (AD), but few non-invasive techniques exist for monitoring the cells after administration. Here we present a magnetic resonance imaging (MRI) technique for tracking microglia injected intra-arterially in vivo. We micro-injected Abeta42 into the left hippocampus and saline into the right hippocampus of rats. We then administered microglia, which were labeled with enhanced green fluorescent protein (EGFP) gene and Resovist, into the carotid artery. After monitoring exogenously administered microglia using MRI, we compared the MR images and the histochemical localization of administered microglia. MRI revealed clear signal changes attributable to Resovist-containing microglia in Abeta-injected areas. Histochemistry demonstrated that EGFP-positive microglia accumulated around Abeta deposits and internalized the peptide. This study demonstrates the usefulness of MRI for non-invasive monitoring of exogenous microglia, and suggests a promising future for microglia/macrophages as therapeutic tools for AD.

Amyloid beta-Peptides↗
PubMed2005

Enhanced vagal modulation and exercise induced ischaemia of the inferoposterior myocardium.

OBJECTIVE: To determine whether the Bezold-Jarisch reflex or enhancement of vagal nerves, which are preferentially distributed in the inferoposterior myocardium, results from exercise induced ischaemia in this region. METHODS: On the basis of exercise myocardial scintigraphy and coronary angiography, 145 patients were classified as follows: group I, 34 patients with inferoposterior ischaemia; group A, 32 with anterior ischaemia; and control, 79 without ischaemia. The relation between ischaemic areas and ECG leads with ST segment changes and vagal modulation assessed by heart rate variability (HRV) (high frequency (HF) component (0.15-0.40 Hz) and coefficient of HF component variance (CCVHF), which is the square root of HF divided by mean RR interval) were assessed. RESULTS: The rate of ST segment depression in any lead did not differ between group I and group A. HF and CCV(HF) were similar before exercise but higher in group I than in group A and the control group after exercise (mean (SEM) HF: 94 (17) ms2, 41 (7) ms2, and 45 (6) ms2, respectively, p = 0.021; CCV(HF): 1.18 (0.09)%, 0.81 (0.07)%, and 0.89 (0.05)%, p = 0.0053). Furthermore, the percentage change in CCV(HF) before and after exercise was higher in group I than in group A or controls (mean (SEM) 22 (10)%, -24 (4)%, and -21 (3)%, p < 0.0001). The optimal cut off for diagnosis of inferoposterior ischaemia was -5% with a sensitivity of 74%, specificity 75%, and accuracy 75%. CONCLUSIONS: Vagal modulation as assessed by HRV analysis was enhanced in association with exercise induced inferoposterior ischaemia. Exercise ECG testing combined with HRV analysis would increase accuracy in the diagnosis of ischaemic areas in selected patients with angina pectoris.

Case-Control Studies↗
PubMed2005

Structure and property of self-assemble valinyl bolaform amides having different chirality.

Bolaform amides were designed from N,N'-bis(carboethoxy-L-valinyl)-diaminoethane (1) by linking t-butyloxycarbonyl-valine through ethylenediamine (EDA) to enable spectroscopic and X-ray diffraction analyses. N,N'-Bis(Boc-L-valinyl)-diaminoethane (2) and N,N'-bis(Boc-D-valinyl)-diaminoethane (3) were composed of L-Val and D-Val, respectively. N-(Boc-L-valinyl)-N'-(Boc-D-valinyl)-diaminoethane (4) was composed of both L-Val and D-Val, and was achiral (meso-peptide). Peptide 5 was a 1:1 mixture of 2 and 3, and was also achiral (racemate). These peptides mediated gelation of corn oil at a concentration of approximately 1%. Within crystals, the peptides formed beta-sheet ribbons, but differences were observed in hydrogen-bonding patterns and side-chain arrangements. These differences were also deduced from temperature dependence of amide protons. Force-field calculations based on the crystal structures indicated that association of beta-sheet ribbons had energy benefits, and it was assumed that molecular aggregation progressed spontaneously. These structural studies indicated the chirality of amino acids affected for the properties of bolaform amides.

Amides↗
PubMed2005

Optic disc topographic parameters measured in the normal cynomolgus monkey by confocal scanning laser tomography.

AIM: To study optic disc topographic parameters in normal cynomolgus monkeys by Heidelberg retina tomograph (HRT). METHODS: 12 optic disc topographic parameters were investigated in 36 normal eyes in 18 male monkeys. Mean (SD) and interocular differences were obtained for each parameter from three independent measurements made during a 1 week period. Correlations among the topographic parameters were analysed, too. RESULTS: No significant differences between right and left eyes were detected for any topographic parameters. Disc area, rim area, and height variation contour showed smaller right-left differences than other parameters. The coefficients of variation for rim area, height variation contour, rim volume, mean cup depth, maximum cup depth, mean retinal nerve fibre layer (RNFL) thickness, and RNFL cross section area were less than 10% (for rim area, less than 5%). Rim area and height variation contour showed relatively weak interrelations and neither showed a correlation with disc area. CONCLUSION: For evaluating time related changes in the optic disc by HRT in monkeys, rim area and height variation contour might be useful parameters because coefficients of variation and right-left differences were lower than for other parameters and because these parameters showed weak interrelations and no correlation with disc area.

Animals↗
PubMed2005

[Pulmonary pleomorphic carcinoma; report of a case].

We report a case of a 64-year-old man with pleomorphic carcinoma of the lung and thymic cyst. He was admitted to our hospital because of an abnormal shadow observed on chest X-ray. Computed tomography (CT) showed a mass lesion located in the right upper lobe and a non-invasive anterior mediastinal tumor adjacent to the left brachiocepharic vein. On enhanced CT, the lung mass showed central low-attenuation areas with a substantial enhancement in the periphery. Preoperative transbronchial blushing cytology of the mass revealed adenocarcinoma. With a diagnosis of primary lung cancer (cT3N0M0) and mediastinal tumor, an operation was performed through a median sternotomy. The mediastinal tumor was excised and a right upper lobectomy and were also accomplished, because the lung tumor did not show adhesion or pleural invasion. Histopathologic examination of the resected specimen revealed that the lung tumor composed of a mixture of spindle and giant cell features and contained a component of adenocarcinoma and squamous cell carcinoma. This finding yielded a pathological diagnosis of pleomorphic carcinoma (pT2N0M0). The mediastinal tumor was diagnosed as thymic cyst. The postoperative course was uneventful, and he is currently well 6 months after surgery.

Adenocarcinoma↗
PubMed2004

Agrobacterium tumefaciens-mediated transformation of embryogenic tissue and transgenic plant regeneration in Chamaecyparis obtusa Sieb. et Zucc.

A genetic transformation procedure for Chamaecyparis obtusa was developed after co-cultivation of embryogenic tissues with disarmed Agrobacterium tumefaciens strain C58/pMP90, which harbours the sgfp (synthetic green fluorescent protein) visual reporter and nptII (neomycin phoshotransferase II) selectable marker genes. The highest transformation frequency was 22.5 independent transformed lines per dish (250 mg embryogenic tissue) following selection on kanamycin medium. Transgenic plantlets were regenerated through the maturation and germination of somatic embryos. The intensity of GFP fluorescence, observed under a fluorescence microscope, varied from very faint to relatively strong, depending on the transgenic line or part of the transgenic plant. The integration of the genes into the genome of regenerated plantlets was confirmed by Southern blot analysis.

Agrobacterium tumefaciens↗
PubMed2004

Somatic embryogenesis and plant regeneration from immature zygotic embryos of Hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.).

We established a plant regeneration system for Hinoki cypress (Chamaecyparis obtusa) via somatic embryogenesis. Embryogenic tissues were successfully induced on three kinds of Smith media from megagametophyte explants containing pre-cotyledonary embryos of C. obtusa plus-trees. Factors affecting somatic embryo maturation were examined. The concentration of polyethylene glycol 4000 in the medium was a critical factor for embryo maturation and its effective concentration was 150 g/l. The addition of 30 g/l maltose to the medium had a positive effect on embryo maturation, but sucrose was ineffective. The mature somatic embryos germinated at a germination frequency of approximately 60%, and the presence of activated charcoal was effective in stimulating plantlet growth. The plantlets acclimatized successfully in a greenhouse. To our knowledge, this is first report describing details of a plant regeneration method for C. obtusa via somatic embryogenesis.

Cell Culture Techniques↗
PubMed2004

Achievement of ultralow emittance beam in the accelerator test facility damping ring.

For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest vertical emittance achieved in single-bunch-mode operation of the Accelerator Test Facility, which satisfies the requirement of the x-band linear collider. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured at low intensity is 4 pm at a beam energy of 1.3 GeV, which corresponds to the normalized emittance of 1.0x1.0(-8) m. It increases by a factor of 1.5 for a bunch intensity of 10(10) electrons. The measured data agreed to the calculation of intrabeam scattering within much better than a factor of 2.

Journal Article↗
PubMed2004

Formation of advanced tokamak plasmas without the use of an ohmic-heating solenoid.

A new operational scenario of advanced tokamak formation was demonstrated in the JT-60U tokamak. This was accomplished by electron cyclotron and lower hybrid waves, neutral beam injection, and the loop voltage supplied by the vertical field and shaping coils. The Ohmic heating (OH) solenoid was not used but a small inboard coil (part of the shaping coil), providing less than 20% of total poloidal flux, was used. The plasma thus obtained had both internal and edge transport barriers, with an energy confinement time of 1.6 times H-mode scaling, a poloidal beta of 3.6, and a normalized beta of 1.6, and a large bootstrap current fraction (>90%). This result opens up a possibility to reduce, and eventually eliminate, the OH solenoid from a tokamak reactor, which will greatly improve its economic competitiveness.

Journal Article↗
PubMed2004

Effective doses of vecuronium in a patient with myotonic dystrophy.

Of the forms of muscular dystrophy, myotonic dystrophy has the greatest systemic involvement. Although most patients with myotonic dystrophy show normal sensitivity to non-depolarising neuromuscular blocking drugs, some have been reported to show greatly increased sensitivity to these drugs, and little is known about the sensitivity of different muscles. We compared effective doses of vecuronium in a patient with myotonic dystrophy at the orbicularis oculi, adductor pollicis and flexor hallucis brevis muscles during total intravenous anaesthesia. The calculated ED50 for the orbicularis oculi (7.77 microg x kg(-1) (95% CI 3.10-16.8 microg x kg(-1))) was lower than for the adductor pollicis (25.3 microg x kg(-1) (95% CI 20.7-43.3 microg x kg(-1))) and flexor hallucis brevis muscles (29.5 microg x kg(-1) (95% CI 11.0-85.6 microg x kg(-1); p < 0.01)). The ED90 was also lower for the orbicularis oculi (35.7 microg x kg(-1) (95% CI 14.8-66.5 microg x kg(-1))) than for the other muscles (51.8 microg x kg(-1) (95% CI 29.3-145.0 microg x kg(-1)) and 50.6 microg x kg(-1) (95% CI 5.29-642.0 microg x kg(-1)), respectively) (p < 0.01)).

Adult↗
PubMed2003

Interleukin-1beta converting enzyme subfamily inhibitors prevent induction of CD86 molecules by butyrate through a CREB-dependent mechanism in HL60 cells.

To investigate the underlying mechanism for induction of CD86 molecules, we analysed the ability of the histone deacetylase (HDAC) inhibitor, sodium butyrate (NaB), to induce CD86 at the transcriptional level in HL60 cells. Our studies showed that the expression of CD86 on the cell surface was increased by 24 hr of NaB treatment, and the enhancement of CD86 mRNA expression was observed by real-time polymerase chain reaction. When we measured NF-kappaB binding activity, significant activity was induced upon NaB stimulation, which was suppressed by the addition of pyrrolidine dithiocarbamate. Butyrate also induced phosphorylated cAMP response element-binding protein (CREB), which bound to cAMP-responsive elements. Dibutyryl (db) -cAMP induced active CREB and increased the levels of CD86 by 24 hr. These observations indicated that NF-kappaB and/or CREB are crucial for butyrate-dependent activation of CD86 gene expression. We examined the inhibitory effects of various caspase inhibitors on the expression of CD86 in cells treated with NaB, because NaB also induced apoptosis with slow kinetics. Intriguingly, our results demonstrated that inhibitors of the interleukin-1beta converting enzyme subfamily (caspase-1, -4, -5 and -13) blocked the butyrate-induced increase in level of CD86. These inhibitors interfered with CD86 gene transcription in the presence of activated NF-kappaB, whereas phosphorylated CREB was down-regulated in the reactions where these inhibitors were added to inhibit CD86 gene expression. These results suggested that butyrate not only acetylates histones on the CD86 promoter through the suppression of HDAC activity, but that butyrate also regulates CREB-mediated transcription, possibly through the caspase activities triggered by NaB.

Antigens, CD↗
PubMed2002

Effect of asymmetric modification on the conformation of ascidiacyclamide analogs.

Ascidiacyclamide (ASC), cyclo(-Ile1-Oxz2-d-Val3-Thz4-)2 (Oxz=oxazoline and Thz=thiazole) has a C2-symmetric sequence, and the relationships between its conformation and symmetry have been studied. In a previous study, we performed asymmetric modifications in which an Ile residue was replaced by Gly, Leu or Phe to disturb the symmetry [Doi et al. (1999) Biopolymers49, 459-469]. In this study, the modifications were extended. The Ile1 residue was replaced by Gly, Ala, aminoisobutyric acid (Aib), Val, Leu, Phe or d-Ile, and the d-Val3 residue was replaced by Val. The structures of these analogs were analyzed by X-ray diffraction, 1H NMR and CD techniques. X-Ray diffraction analyses revealed that the [Ala1], [Aib1] and [Phe1]ASC analogs are folded, whereas [Val1]ASC has a square form. These structures are the first examples of folded structures for ASC analogs in the crystal state and are similar to the previously reported structures of [Gly1] and [Phe1]ASC in solution. The resonances of amide NH and Thz CH protons linearly shift with temperature changes; in particular, those of [Aib1], [d-Ile1] and [Val3]ASCs exhibited a large temperature dependence. DMSO titration caused nonlinear shifts of proton resonances for all analogs and largely affected [d-Ile1] and [Val3]ASCs. A similar tendency was observed upon the addition of acetone to peptide solutions. Regarding peptide concentration changes, amide NH and Thz CH protons of [Gly1]ASC showed a relatively large dependence. CD spectra of these analogs indicated approximately two patterns in MeCN solution, which were related to the crystal structures. However, all spectra showed a similar positive Cotton effect in TFE solution, except that of [Val3]ASC. In the cytotoxicity test using P388 cells, [Val1]ASC exhibited the strongest activity, whereas the epimers of ASC ([d-Ile1] and [Val3]ASCs), showed fairly moderate activities.

Amino Acid Substitution↗