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H Fujimura

Publications and source records attributed to H Fujimura.

At least 19 recordsLinked to original sources
PubMed2006

Differential cross section and photon-beam asymmetry for the gamma n --> K+ Sigma- reaction at E gamma = 1.5-2.4 GeV.

Differential cross sections and photon-beam asymmetries have been measured for the gamma n --> K+ Sigma- and gamma p --> K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of E gamma = 1.5-2.4 GeV at 0.6 < cos ThetacmK< 1. The cross section ratio of sigma K+ Sigma-/sigma K+ Sigma0, expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+ Sigma- reaction, large positive asymmetries are observed, indicating the dominance of K* exchange. The large difference between the asymmetries for the K+ Sigma- and K+ Sigma0 reactions cannot be explained by simple theoretical considerations based on Regge model calculations.

Journal Article↗
PubMed2005

Near-threshold diffractive psi-meson photoproduction from the proton.

Photoproduction of a phi meson on protons was studied by means of linearly polarized photons at forward angles in the low-energy region from threshold to Egamma = 2.37 GeV. The differential cross sections at t = -|t|min do not increase smoothly as Egamma increases but show a local maximum at around 2.0 GeV. The angular distributions demonstrate that phi mesons are photoproduced predominantly by helicity-conserving processes, and the local maximum is not likely due to unnatural-parity processes.

Journal Article↗
PubMed2003

Beam-polarization asymmetries for the p(gamma-->, K+)Lambda and p(gamma-->, K+)Sigma(0) reactions for E(gamma)=1.5-2.4 GeV.

Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6<cos((theta(c.m.)(K+))<1.0 by using linearly polarized photons at the Laser-Electron-Photon facility at SPring-8 (LEPS). The observed asymmetries are positive and gradually increase with rising photon energy. The data are not consistent with theoretical predictions based on tree-level effective-Lagrangian approaches. Including the new results in the development of the models is, therefore, crucial for understanding the reaction mechanism and to test the presence of baryon resonances which are predicted in quark models but are thus far undiscovered.

Journal Article↗
PubMed2003

Evidence for a narrow S = +1 baryon resonance in photoproduction from the neutron.

The gamman-->K(+)K(-)n reaction on 12C has been studied by measuring both K+ and K- at forward angles. A sharp baryon resonance peak was observed at 1.54+/-0.01 GeV/c(2) with a width smaller than 25 MeV/c(2) and a Gaussian significance of 4.6sigma. The strangeness quantum number (S) of the baryon resonance is +1. It can be interpreted as a molecular meson-baryon resonance or alternatively as an exotic five-quark state (uuddsmacr;) that decays into a K+ and a neutron. The resonance is consistent with the lowest member of an antidecuplet of baryons predicted by the chiral soliton model.

Journal Article↗
PubMed2003

Excitation and decay of the isovector giant monopole resonances via the 208Pb(3He,t p) reaction at 410 MeV.

The excitation and subsequent proton decay of the isovector spin-flip giant monopole resonance (IVSGMR) is studied via the 208Pb(3He,t) reaction at 410 MeV. In the inclusive spectrum (60+/-5)% of the non-energy-weighted sum-rule strength for this 2 variant Planck's over 2h omega resonance was found in the region 29<Ex(208Bi)<51 MeV. The central excitation energy and width of the IVSGMR are 37+/-1 MeV and 14+/-3 MeV, respectively. It is found that the branching ratio for proton decay is (52+/-12)% and that the deep neutron-hole states in 207Pb are strongly fed.

Journal Article↗
PubMed2002

Decreased hepatobiliary transport of methotrexate in adjuvant arthritis rats.

1. We investigated the difference in hepatobiliary transport of methotrexate in normal and adjuvant arthritis (AA) rats and substantiated the expression level of multidrug resistance-associated protein 2 (MRP2) in the liver. 2. Biliary clearance of methotrexate in normal and AA rats was calculated from plasma concentrations and biliary excretion following intravenous infusion and hepatic uptake clearance was estimated from an integration plot using methotrexate concentrations in plasma and liver. 3. Biliary clearance of methotrexate in AA rats was 2.30 +/- 0.23 ml min(-1) kg(-1) (mean SD) and significantly lower than in normal rats (8.42 +/- 0.81 ml min(-1) kg(-1)). The uptake clearance of methotrexate in AA rats was also lower than in normal rats (0.138 versus 0.278 ml min(-1) g liver(-1)). 4. MRP2 in the liver was detected by fluorescein isothiocyanate-labelled antibody and visualized using a confocal laser microscope system. The expression level of MRP2 in AA rats was very low compared with normal rats, indicating a down-regulation in AA rats. 5. In conclusion, biliary clearance of methotrexate was decreased due to the lower activities in both uptake and canalicular secretion, suggesting that several active transporters in the liver, including MRP2, are down-regulated in AA rats.

Animals↗
PubMed2002

Recovery process of arthritis induced by 6-sulfanilamidoindazole (6SAI) in rats.

6-Sulfanilamidoindazole (6SAI) is known to induce not only an acute arthritis but also serositis and arteritis which resemble those induced by some vasodilators in rats. In this study, the recovery process of ankle lesions was examined histopathologically for up to 12 weeks of recovery period in rats bearing arthritis induced by administration of 6SAI (500 mg/kg) for 2 weeks. At 2 weeks of 6SAI-treatment, exudative synovitis and exudative/edematous periarthritis with marked formation of granulation tissues and periosteal reactive bone formation were noted in the ankles, but no remarkable neutrophil infiltration was detected in those lesions. The ankle swelling induced by 6SAI diminished by 4 weeks of recovery period, and the elevated plasma fibrinogen levels were normalized by 2 weeks of recovery period. Although fibrosis and newly-formed periosteal bone were still observed after 2 weeks of recovery period, no inflammatory lesion was detected at that point. At 4 or 12 weeks of recovery periods, the ankles showed an almost normal appearance. These results indicate that 6SAI-induced arthritis is reversible in nature and does not develop into chronic phase.

Acute Disease↗
PubMed2001

Dipole excitation of alpha clusters in (6)Li and (7)Li.

Dipole excitations in highly excited energy regions of (6)He and (7)He nuclei were investigated via the ((7)Li,(7)Be) reaction with an incident energy of 65A MeV at forward scattering angles. The resonances at Q approximately equal to -30 MeV observed commonly for both (6)Li and (7)Li targets were found to be excited via both spin-flip and spin-nonflip transitions with DeltaL = 1. Based on the observed excitation energy, width, and cross section of each resonance, the relevant resonances are inferred to be analogs of the dipole resonances of alpha clusters in the (6)Li and (7)Li nuclei.

Journal Article↗
PubMed2001

Dynamics of antigen-specific helper T cells at the initiation of airway eosinophilic inflammation.

Bronchial asthma is characterized by chronic eosinophilic inflammation of the bronchial mucosa in which Th2 cells play crucial roles. Ovalbumin-reactive Th2 clones were labeled with a fluorescent-probe then infused into unprimed mice to elucidate the dynamics of antigen-specific T cells involved in allergic inflammation. Infiltration of not only labeled antigen-specific T cells, but also unlabeled nonspecific CD4(+) T cells into the bronchial mucosa following inhaled antigen challenge was detectable under confocal microscopy and flow cytometry. Accordingly, labeled T cells in the spleen were decreased, whereas those in hilar lymph nodes were increased upon antigen challenge. Approximately 45% of antigen-specific T cells that migrated into the lungs bore CD25, while another early activation marker, CD69, was expressed on 80% of the migrated T cells. Accordingly, antigen challenge to the mice induced in situ proliferation of antigen-specific T cells as well as bronchial epithelial cells in the lungs. Expression of vascular cell adhesion molecule (VCAM)-1, but not intercellular adhesion molecule (ICAM)-1, on the vascular endothelium in the lungs was enhanced following antigen challenge. Nevertheless, treatment with anti-VCAM-1 antibody, and also anti-ICAM-1 antibody strongly suppressed the accumulation of T cells, suggesting that both VCAM-1 and ICAM-1 are essential for antigen-stimulated T cell mobilization into peripheral tissues. Our current study visualized the kinetics and the mechanism of antigen-specific T cell migration in response to local challenge with a protein antigen.

Adoptive Transfer↗
PubMed2001

The Saccharomyces cerevisiae MLF6/YPL244C gene, which encodes a possible yeast homologue of mammalian UDP-galactose transporter, confers resistance to the immunosuppressive drug, leflunomide.

The immunosuppressant leflunomide (LFM) inhibits the growth of cytokine-stimulated proliferation of lymphoid cells in vitro and also inhibits the growth of eukaryotic microorganism, Saccharomyces cerevisiae. As a first step to elucidate the molecular mechanism of LFM action in human, yeast gene which suppresses the anti-proliferative effect when in increased copy number was cloned and designated MLF6 for multicopy suppressor of LFM sensitivity. DNA sequencing analysis revealed that the MLF6 gene is identical to the YPL244C gene which encodes a possible yeast homologue of human UDP-galactose transporter. The disruption of the MLF6 gene increased the sensitivity of yeast cells to the drug.

Amino Acid Sequence↗
PubMed2001

Copper chaperone for superoxide dismutase co-aggregates with superoxide dismutase 1 (SOD1) in neuronal Lewy body-like hyaline inclusions: an immunohistochemical study on familial amyotrophic lateral sclerosis with SOD1 gene mutation.

The copper chaperone for superoxide dismutase (CCS) interacts with Cu/Zn-binding superoxide dismutase 1 (SOD1) specifically and delivers copper to SOD1. To determine the role of the CCS-SOD1 interaction in the pathogenesis of SOD1-mutated familial amyotrophic lateral sclerosis (FALS) patients, we produced an affinity-purified rabbit antibody against CCS and investigated the immunohistochemical localization of both CCS and SOD1 in neuronal Lewy body-like hyaline inclusions (LBHIs) in the spinal cords of two FALS patients with a two-base pair deletion at codon 126 in the SOD1 gene and three FALS patients with an Ala to Val substitution at codon 4. The LBHIs in anterior horn cells from the five FALS patients showed identical immunoreactivities for CCS: the reaction product deposits with the antibody against CCS were generally restricted to the periphery of the core and halo-type LBHIs. The localizations of the immunoreactivities for CCS and SOD1 were similar in the inclusions: both CCS and SOD1 colocalized in neuronal LBHIs in the five mutant SOD1-linked FALS patients. Our results suggest that the specific interaction and aggregation of CCS-SOD1 (probably CCS-mutant SOD1) in SOD1-mutated FALS patients may amplify the formation of inclusions and emphasize a more marked mutant SOD1-mediated toxicity.

Adult↗
PubMed2001

Optimal doses of paclitaxel and carboplatin combination chemotherapy for ovarian cancer: a phase I modified continual reassessment method study.

BACKGROUND: A multicenter, phase I study of combination therapy with paclitaxel and carboplatin for epithelial ovarian cancer was conducted to determine the safety and recommended dosages for Japanese women. METHODS: Paclitaxel was administered intravenously over a 3-h period, followed by carboplatin administered intravenously over a 1.5-h period. A modified continual reassessment method (mCRM) was used in two treatment arms to establish the maximum tolerated dose (MTD) and recommended doses of the combination. In group A, the dose of paclitaxel (175 mg/m2) was constant and the dose of carboplatin was increased from 4 to 7 in terms of the target area under the plasma concentration-versus-time curve (AUC). In group B, the dose of carboplatin was constant (AUC 6) and paclitaxel was administered at two dose levels (160 and 175 mg/m2). In both groups, the carboplatin dose was limited to a maximum of 800 mg/body for each administration. RESULTS: Because the calculated probability of toxicity was greatest at a dose of paclitaxel 175 mg/m2 and carboplatin AUC 7, this dose was designated the MTD in group A. Based on this result, treatment in group B was initiated at doses of paclitaxel of 160 mg/m2 and carboplatin AUC 6. While the dose of paclitaxel was escalated to 175 mg/m2, the safety of the combination was confirmed. The most frequent adverse effect was neutropenia, which resolved promptly with the appropriate use of granulocyte-colony stimulating factor (G-CSF). No other severe hematologic or nonhematologic toxicities were observed. CONCLUSIONS: Our study demonstrated that the recommended dose for this combination regimen should be paclitaxel 175 mg/m2 plus carboplatin AUC 6 (maximum dose, 800 mg/body).

Adenocarcinoma, Clear Cell↗
PubMed2001

Reduction of metallothioneins promotes the disease expression of familial amyotrophic lateral sclerosis mice in a dose-dependent manner.

We previously reported that abnormal copper release from mutated Cu, Zn-superoxide dismutase (SOD1) proteins might be a common toxic gain-of-function in the pathogenesis of familial amyotrophic lateral sclerosis (FALS) [Ogawa et al. (1997) Biochem. Biophys. Res. Commun., 241, 251-257.]. In the present study, we first examined metallothioneins (MTs), known to bind copper ions and decrease oxidative toxicity, and found a twofold increase in MTs in the spinal cord of the SOD1 transgenic mice with a FALS-linked mutation (G93A), but not in the spinal cord of wild-type SOD1 transgenic mice. We then investigated whether the clinical course of FALS mice could be modified by the reduced expression of MTs, by crossing the FALS mice with MT-I- and MT-II-deficient mice. FALS mice clearly reached the onset of clinical signs and death significantly earlier in response to the reduction of protein expression. These results indicated that the copper-mediated free radical generation derived from mutant SOD1 might be related to the degeneration of motor neurons in FALS and that MTs might play a protective role against the expression of the disease.

Amyotrophic Lateral Sclerosis↗
PubMed2001

Correlation between eosinophilia induced by CD4(+) T cells and bronchial hyper-responsiveness.

The relationship between CD4(+) T cell-mediated airway eosinophilic inflammation and bronchial hyper-responsiveness (BHR) was investigated. Ovalbumin-reactive T(h)0 clones were adoptively transferred to unprimed BALB/c mice and then the mice were challenged by inhalation of the relevant antigen. Upon antigen provocation, infused T(h) clones infiltrated into the airways, followed by the accumulation and degranulation of eosinophils, goblet cell hyperplasia, edema and increase in bronchial responsiveness to acetylcholine. Transfer of several clones that differed in the levels of IL-5 production revealed that the magnitude of in vivo eosinophilia strongly correlated with the IL-5-producing capacity of the infused T(h) clones. Administration of anti-IL-5 mAb almost completely suppressed antigen-induced eosinophilic inflammation and BHR. Administration of anti-IL-4 mAb or anti-IFN-gamma mAb enhanced the eosinophilia and BHR, whereas anti-IL-2 mAb did not affect them. The number of accumulated eosinophils significantly correlated with the intensity of BHR. Our present results clearly demonstrated that CD4(+) T cells induced BHR as a result of eosinophilic inflammation. IL-5 totally regulated both responses.

Acetylcholine↗
PubMed2001

Improvement of anti-Hu-associated paraneoplastic sensory neuropathy after chemoradiotherapy in a small cell lung cancer patient.

A 66-year-old man developed progressive painful dysesthesia in his hands and feet over 3 months. His vibration sense was impaired and sensory nerve action potentials of the limbs were not evoked. Biopsy of the peroneal nerve revealed sensory neuropathy. Positive anti-Hu antibody facilitated delineation of a right hilar mass and a metastatic lymph node in thoracic CT scan. He was diagnosed as small cell lung cancer associated with paraneoplastic sensory neuropathy. A complete response was achieved through chemotherapy (carboplatin and etoposide) and subsequent radiation therapy. Notably, his neurological conditions, although not changed during the hospitalization, gradually improved afterwards.

Aged↗
PubMed2000

The expression of ion channel mRNAs in skeletal muscles from patients with myotonic muscular dystrophy.

We investigated gene expression patterns of ion channels including the apamin-sensitive small-conductance Ca(2+)-activated K(+) (SK3) channel, the adult isoform of the skeletal muscle Na(+) channel (SkM1), the fetal isoform of skeletal muscle Na(+) channel (H1), and the Cl(-) channel (ClC-1) by using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) for muscle samples from patients with adult onset myotonic dystrophy (DM), amyotrophic lateral sclerosis, and polymyositis. Patients with DM showed a significant increase in SK3 mRNA but not in mRNAs for other ion channels. The increased expression of SK3 gene in DM did not correlate with H1, the marker of muscle denervation, or the percentage of type 2C fiber, the marker of muscle regeneration.

Adult↗