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T Ishida

Publications and source records attributed to T Ishida.

At least 37 records · Page 2Linked to original sources
PubMed2005

Radiation safety assessment of a system of small reactors for distributed energy.

A passively safe small reactor for a distributed energy system, PSRD, is an integral type of light-water reactor with a thermal output of 100 or 300 MW aimed to be used for supplying district heat, electricity to small grids, and so on. Candidate locations for the PSRD as a distributed energy source are on-ground, deep underground, and in a seaside pit in the vicinity of the energy consumption area. Assessments of the radiation safety of a PSRD were carried out for three cases corresponding to normal operation, shutdown and a hypothetical postulated accident for several siting candidates. Results of the radiation safety assessment indicate that the PSRD design has sufficient shielding performance and capability and that the exposure to the general public is very low in the case of a hypothetical accident.

Algorithms↗
PubMed2005

Inter- and intra-specific gene-density-correlated radial chromosome territory arrangements are conserved in Old World monkeys.

Recently it has been shown that the gene-density correlated radial distribution of human 18 and 19 homologous chromosome territories (CTs) is conserved in higher primates in spite of chromosomal rearrangements that occurred during evolution. However, these observations were limited to apes and New World monkey species. In order to provide further evidence for the evolutionary conservation of gene-density-correlated CT arrangements, we extended our previous study to Old World monkeys. They comprise the remaining species group to be analyzed in order to obtain a comprehensive overview of the nuclear topology of human 18 and 19 homologous CTs in higher primates. In the present study we investigated four lymphoblastoid cell lines from three species of Old World monkeys by three-dimensional fluorescence in situ hybridization (3D-FISH): two individuals of Japanese macaque (Macaca fuscata), crab-eating macaque (Macaca fascicularis), and an interspecies hybrid individual between African green monkey (Cercopithecus aethiops) and Patas monkey (Erythrocebus patas). Our data demonstrate that gene-poor human 18 homologous CTs are located preferentially close to the nuclear periphery, whereas gene-dense human 19 homologous CTs are oriented towards the nuclear center in all cell lines analyzed. The gene-density-correlated positioning of human 18 and 19 homologous CTs is evolutionarily conserved throughout all major higher primate lineages, despite chromosomal inversions, fusions, fissions or reciprocal translocations that occurred in the course of evolution in these species. This remarkable preservation of a gene-density-correlated chromatin arrangement gives further support for a functionally relevant higher-order chromatin architecture.

Animals↗
PubMed2004

Nonspecific interstitial pneumonia pattern as pulmonary involvement of rheumatoid arthritis.

The pathologic patterns of lung involvement were evaluated in 16 patients with rheumatoid arthritis (RA). They consisted of six females and ten males, with a median age of 67.5 years and diagnosed according to the American Rheumatism Association revised criteria. High-resolution computed tomography (HRCT) of the lungs was performed in all patients, and honeycomb formation was apparent in seven. Histopathologically, seven patients were diagnosed with usual interstitial pneumonia (UIP) pattern, seven with nonspecific interstitial pneumonia/fibrosis (NSIP) pattern, and two with UIP/NSIP hybrid pattern. There were no apparent honeycomb formations on HRCT in patients diagnosed with NSIP pattern. In conclusion, the present study demonstrates that NSIP pattern is also a significant histologic classification of interstitial pneumonia associated with RA.

Aged↗
PubMed2004

High rates of primary care and emergency department use among injection drug users in Vancouver.

BACKGROUND: Frequent use of emergency rooms by injection drug users (IDUs) has been attributed to a lack of access to primary care and barriers to health services. Using a community-based sample of IDUs, we examined rates of primary care and emergency room use among IDUs and identified correlates of frequent emergency department use. METHODS: From January to November 2003, we enrolled IDUs into a prospective cohort study involving a baseline questionnaire, comprehensive retrospective and prospective health record linkages. We examined rates of primary care and emergency department utilization, and diagnoses upon arrival in the emergency room. Logistic regression was used to determine factors independently associated with frequent emergency room use. RESULTS: Of the 883 IDUs included in this analysis, 687 (78 per cent) accessed a primary care clinic in the previous year, while 528 (60 per cent) participants accessed the emergency room (ER) during the years 2002 and 2003. Abscesses, cellulitis and other skin infections accounted for the greatest proportion of ER use. Factors independently associated with frequent ER use included: frequent crystal methamphetamine injection (AOR = 2.4, 95 per cent CI: 1.0-5.6); non-fatal overdose (AOR = 2.1, 95 per cent CI: 1.4-3.3); HIV-positive status (AOR = 1.5, 95 per cent CI: 1.1-2.1), having been physically assaulted (AOR = 1.5, 95 per cent CI: 1.1-2.1); and primary care utilization (AOR = 1.5, 95 per cent CI: 1.0-2.1). DISCUSSION: high rates of ER use were observed among IDUs, despite high rates of primary care use among this same population. ER use was due primarily to preventable injection-related complications that are less amenable to primary care interventions, and therefore educational and prevention efforts that encourage and enable sterile injection practices should be promoted.

Adult↗
PubMed2004

Evidence for an oscillatory signature in atmospheric neutrino oscillations.

Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3) 0.90 at 90% confidence level.

Journal Article↗
PubMed2004

Search for electron neutrino appearance in a 250 km long-baseline experiment.

We present a search for electron neutrino appearance from accelerator-produced muon neutrinos in the K2K long-baseline neutrino experiment. One candidate event is found in the data corresponding to an exposure of 4.8 x 10(19) protons on target. The expected background in the absence of neutrino oscillations is estimated to be 2.4+/-0.6 events and is dominated by misidentification of events from neutral current pi(0) production. We exclude the nu(micro) to nu(e) oscillations at 90% C.L. for the effective mixing angle in the 2-flavor approximation of sin((2)2theta(microe)( approximately 1/2sin((2)2theta(13))>0.15 at Deltam(2)(microe)=2.8 x 10(-3) eV(2), the best-fit value of the nu(micro) disappearance analysis in K2K. The most stringent limit of sin((2)2theta(microe)<0.09 is obtained at Deltam(2)(microe)=6 x 10(-3) eV(2).

Journal Article↗
PubMed2004

Limits on the neutrino magnetic moment using 1496 days of Super-Kamiokande-I solar neutrino data.

A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)</=(3.6x10(-10))micro(B) at 90% C.L. by fitting to the Super-Kamiokande day-night spectra. The fitting took into account the effect of neutrino oscillation on the shapes of energy spectra. With additional information from other solar neutrino and KamLAND experiments constraining the oscillation region, a limit of micro(nu)</=(1.1x10(-10))micro(B) at 90% C.L. was obtained.

Journal Article↗
PubMed2004

Inactivation of class II transactivator by DNA methylation and histone deacetylation associated with absence of HLA-DR induction by interferon-gamma in haematopoietic tumour cells.

By presenting immunogenic peptides at the cell surface, major histocompatibility complex (MHC) class II molecules play a key role in the control of adaptive immune responses. Whether expressed constitutively or induced by interferon-gamma, expression of MHC class II molecules is regulated via coactivator class II transactivator (CIITA); moreover, suppression of their expression is one mechanism by which cancer cells escape host immunity. In this study, we surveyed the relationship between the expression of one MHC class II antigen, HLA-DR, and its coactivators in a group of haematopoietic cell lines, and explored the role of the aberrant DNA methylation in silencing HLA-DR expression. Among 26 cell lines studied, HLA-DR expression was lost from eight T-cell and two myeloid leukaemia cell lines, and this loss was closely associated with suppression of CIITA-PIV expression. Notably, nine of the 10 cell lines that lost CIITA-PIV expression showed methylation of the gene's 5' CpG island. Thus, DNA methylation is believed to inhibit the expression of MHC class II molecules in haematopoietic tumour cells by silencing its coactivator, CIITA-PIV. Furthermore, methylation of CIITA-PIV was detected in seven of 32 primary acute myeloid leukaemia specimens, indicating that epigenetic alteration is not a cell line-specific phenomenon. Collectively, these data suggest that, by suppressing expression of MHC class II molecules, epigenetic inactivation of CIITA provides a survival advantage to a subset of haematopoietic tumours.

Acetylation↗
PubMed2004

Use of recombinant feline interferon and glucocorticoid in the treatment of feline infectious peritonitis.

A total of 12 clinically ill cats previously diagnosed as feline infectious peritonitis (FIP) were treated with a combination of recombinant feline interferon and glucocorticoid. A complete remission (over 2 years) and a partial remission (2 to 5 months) were observed in four (33.3%) and four (33.3%) cases, respectively. Those that survived for more than 2 years were all older cats (6 to 16 years old) with the effusive form of FIP.

Animals↗
PubMed2004

Elevation of cytokeratin 19 fragment (CYFRA 21-1) in serum of patients with radiation pneumonitis: possible marker of epithelial cell damage.

Cytokeratin 19 fragment (CYFRA 21-1) level in serum have already been documented as a useful tumor marker for lung cancer. In the present study, we hypothesized that CYFRA 21-1 increases in the sera of patients with radiation pneumonitis, resulting from epithelial cell damage. We measured CYFRA 21-1 in the sera of patients with radiation pneumonitis and evaluated the correlation between CYFRA 21-1 level and severity of radiation pneumonitis as well as clinical course. We studied 16 patients diagnosed with radiation pneumonitis associated with primary lung cancer. CYFRA 21-1 levels in the sera of patients with diffuse radiation pneumonitis (n = 6) significantly increased compared to normal smokers (n = 10) or patients with local radiation pneumonitis (n = 10). CYFRA 21-1 values in sera changed according to the progression or improvement of the diffuse radiation pneumonitis. An immunohistochemical study using pulmonary tissues obtained from autopsied patients with radiation pneumonitis demonstrated that the hyaline membrane and proliferating type II pneumocytes were strongly stained by the anti-human cytokeratin 19 antibody. Our data demonstrated that CYFRA 21-1 was increased in patients with diffuse radiation pneumonitis. Since CYFRA 21-1 is widely used as a tumor marker for lung cancer, this evidence should be noted especially in irradiated patients.

Aged↗
PubMed2004

Cis-acting effect of the IL1B C-31T polymorphism on IL-1 beta mRNA expression.

Since the effect of IL1B polymorphisms on IL-1beta production is still controversial, we selected two polymorphisms to test their cis-acting effect on IL-1beta mRNA expression by means of the allele-specific transcript quantification and the haplotype analysis. As for the C-31T polymorphism, we found that expression of the -31T allele was 2.2 times of the -31C allele. This higher transcription efficiency may correspond to the fact that C-31T is located in a TATA box. The other polymorphism, C+3954T, did not alter the levels of transcription. The use of the allele-specific transcript quantification enables us to exclude trans-acting effects of polymorphisms on the gene expression and contributes to understanding the roles of the IL1B polymorphisms in susceptibility to multifactorial diseases.

Cell Line↗
PubMed2004

Constitutively activated phosphatidylinositol 3-kinase primes platelets from patients with chronic myelogenous leukemia for thrombopoietin-induced aggregation.

In this study, we examined the effect of thrombopoietin (TPO) on the aggregation of platelets from 40 patients with myeloproliferative disorders (MPDs), including 17 patients with chronic myelogenous leukemia in the chronic phase (CML-CP), 10 with polycythemia vera, 10 with essential thrombocythemia, and three with myelofibrosis. TPO by itself dose-dependently induced the aggregation of platelets from patients with CML-CP but not from those with other MPDs or with CML-CP in cytogenetical complete remission. The expression of CD63 in CML-CP platelets was induced by TPO treatment. Phosphatidylinositol 3-kinase (PI3-kinase) was constitutively activated in CML-CP platelets. Pretreatment with PI3-kinase inhibitors (wortmannin and LY294002) dose-dependently inhibited TPO-induced aggregation of CML-CP platelets. The Abl kinase inhibitor imatinib mesylate and the Jak inhibitor AG490 suppressed TPO-induced aggregation of CML-CP platelets. Pretreatment with imatinib mesylate, but not with AG490, inhibited the activity of PI3-kinase in CML-CP platelets. In addition, tyrosine phosphorylation of Jak2 was undetected in CML-CP platelets before TPO treatment. These findings indicate that the constitutive activation of PI3-kinase primes CML-CP platelets for the aggregation induced by TPO, and that Bcr-Abl, but not Jak family protein tyrosine kinases, are involved in the constitutive activation of PI3-kinase in CML-CP platelets.

Androstadienes↗
PubMed2004

The effects of veno-venous extracorporeal membrane oxygenation on hypoxic fetal lambs.

OBJECTIVE: The purpose of this study was to determine the applicability of veno-venous extracorporeal membrane oxygenation (V-V ECMO) to support fetal oxygenation in utero. METHODS: An ECMO system with a centrifugal pump was applied to ten chronically instrumented fetal lambs, at 126 or 127 days of gestation. Blood was obtained through a double-lumen catheter inserted into the right atrium. After oxygenation, the blood was returned through a single-lumen catheter into either the carotid artery (veno-arterial; V-A ECMO) or the right atrium (V-V ECMO). After fetal hypoxia had been experimentally produced, V-A ECMO or V-V ECMO was instituted to maintain fetal oxygenation. We compared fetal blood gases with both routes of ECMO. RESULTS: Oxygen partial pressure (pO(2)) in the fetal cranial carotid artery decreased to 12.9 +/- 0.6 mmHg after reducing the fraction inspiratory oxygen of the mother. After instituting V-A ECMO, pO(2) was found to be 23.5 +/- 2.6 mmHg; after instituting V-V ECMO, pO(2) was found to be 20.3 +/- 1.9 mmHg. Thus, fetal acidosis increased under both procedures. Fetal heart rate and blood pressure were not altered significantly during the experiments. CONCLUSIONS: This study indicates that V-V ECMO could more effectively and less traumatically maintain oxygenation in hypoxic fetal lambs.

Animals↗
PubMed2004

Phosphatidylserine receptor cooperates with high-density lipoprotein receptor in recognition of apoptotic cells by thymic nurse cells.

The thymus contains many apoptotic cells that arise from the process of positive and negative selection. Both thymic macrophages and thymic nurse cells/nursing thymic epithelial cells (nursing TECs), non-professional phagocytes, recognize and ingest apoptotic cells without inflammation or tissue damage. Previously we reported that human scavenger receptor class B (SR-B1) is involved in recognition of apoptotic thymocytes by nursing TECs. In this study, we examined the expression and role of a phosphatidylserine receptor (PSR). This receptor is believed to participate in the clearance of apoptotic cells. PSR was strongly expressed in nursing TECs. Transforming growth factor-beta augmented the expression of PSR leading to enhanced binding of apoptotic cells to nursing TECs. In nursing TECs, suppressed expression of human SR-B1 with anti-PSR antibody decreased binding of apoptotic thymocytes to nursing TECs. Our results suggest that both PSR and SR-B1 are expressed in nursing TECs and these receptors appear to play a major role in the clearance of apoptotic cells from the thymus.

Animals↗
PubMed2004

[Mitral regurgitation due to sole punched out lesion of the mitral anterior leaflet in infective endocarditis; report of a case].

Mitral regurgitation (MR) due to only punched out lesion is extremely rare in infective endocarditis. A 31-year-old male was admitted to our hospital due to unusual cause of MR. Echocardiography showed MR due to punched out lesion of the mitral anterior leaflet, which is extremely rare. A round shape punched out lesion (about 16 mm in size) was found intraoperatively in the anterior leaflet of the mitral valve. The surface around the punched out lesion was smooth, and the leaflet displayed good movability. Neither vegetation nor calcification was found. Punched out lesion was successfully closed with autologous pericardial patch and annuloplasty was performed.

Adult↗
PubMed2003

Indications of neutrino oscillation in a 250 km long-baseline experiment.

The K2K experiment observes indications of neutrino oscillation: a reduction of nu(mu) flux together with a distortion of the energy spectrum. Fifty-six beam neutrino events are observed in Super-Kamiokande (SK), 250 km from the neutrino production point, with an expectation of 80.1(+6.2)(-5.4). Twenty-nine one ring mu-like events are used to reconstruct the neutrino energy spectrum, which is better matched to the expected spectrum with neutrino oscillation than without. The probability that the observed flux at SK is explained by statistical fluctuation without neutrino oscillation is less than 1%.

Journal Article↗
PubMed2003

Latent HIV-1 reactivation in transgenic mice requires cell cycle -dependent demethylation of CREB/ATF sites in the LTR.

OBJECTIVE: We previously produced a line of transgenic mice that carried the HIV-1 genome deficient in the gene. Although the HIV-1 genome in the lymphocytes was dormant under normal physiological conditions, it could be reactivated by lipopolysaccharide (LPS) administration via induction of interleukin-1alpha/beta and tumour necrosis factor-alpha. In this report, we analysed further the reactivation mechanism of the latent HIV-1 using this transgenic mouse model. DESIGN: and methods: Possible involvement of CpG methylation in HIV-1 latency was examined by treating transgenic lymphocytes with a demethylating agent, 5'-azacytidine. CpG methylation in the HIV-1 long terminal repeat (LTR) was analysed using the bisulfite genomic sequencing method. As previous studies suggested that CpG demethylation depended on the cell cycle progression, we analysed the relation between cell cycle progression and LPS-induced reactivation of HIV-1 by labelling lymphocytes with an intracellular fluorescein, carboxyfluorescein diacetate succinimidyl ester. RESULTS: We found that 5'-azacytidine enhanced HIV-1 expression ninefold compared to treatment with LPS alone. Furthermore, HIV-1 p24 induction by LPS was observed only in cells that had undergone cell division, while induction was prevented in cells in which cell cycle progression was blocked either by mimosine, aphidicolin, or nocodazole. LPS-induced HIV-1 reactivation was associated with demethylation of two CpG sites located in the CREB/ATF binding sites in the HIV-1 LTR in a cell cycle-dependent manner. CONCLUSIONS: These observations indicate that cell cycle progression-dependent demethylation of the CREB/ATF sites in the LTR is crucial for the reactivation of latent HIV-1 genome in transgenic mice.

Activating Transcription Factors↗