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T Mori

Publications and source records attributed to T Mori.

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

An organic thyristor.

Thyristors are a class of nonlinear electronic device that exhibit bistable resistance--that is, they can be switched between two different conductance states. Thyristors are widely used as inverters (direct to alternating current converters) and for the smooth control of power in a variety of applications such as motors and refrigerators. Materials and structures that exhibit nonlinear resistance of this sort are not only useful for practical applications: they also provide systems for exploring fundamental aspects of solid-state and statistical physics. Here we report the discovery of a giant nonlinear resistance effect in the conducting organic salt theta-(BEDT-TTF)2CsCo(SCN)4, the voltage-current characteristics of which are essentially the same as those of a conventional thyristor. This intrinsic organic thyristor works as an inverter, generating an alternating current when a static direct-current voltage is applied. Whereas conventional thyristors consist of a series of diodes (their nonlinearity comes from interface effects at the p-n junctions), the present salt exhibits giant nonlinear resistance as a bulk phenomenon. We attribute the origin of this effect to the current-induced melting of insulating charge-order domains, an intrinsically non-equilibrium phenomenon in the sense that ordered domains are melted by a steady flow.

Journal Article↗
PubMed2005

Study of B0-->rho+/- pi-/+ time-dependent CP violation at Belle.

We present a time-dependent analysis of CP violation in B0-->rho(+/-)pi(-/+) decays based on a 140 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at KEKB. We obtain the charge asymmetry A(rhopi)(CP)=-0.16+/-0.10(stat)+/-0.02(syst). An unbinned maximum-likelihood fit to the Deltat distributions yields C(rhopi)=0.25+/-0.17(stat)+0.02-0.06(syst), DeltaC(rhopi)=0.38+/-0.18(stat)+0.02-0.04(syst), S(rhopi)=-0.28+/-0.23(stat)+0.10-0.08(syst), and DeltaS(rhopi)=-0.30+/-0.24(stat)+/-0.09(syst). The direct CP violation parameters for B-->rho(+)pi(-) and B-->rho(-)pi(+) decays are A(+-)(rhopi)=-0.02+/-0.16(stat)+0.05-0.02(syst) and A(-+)(rhopi)=-0.53+/-0.29(stat)+0.09-0.04(syst).

Journal Article↗
PubMed2005

Observation of an isotriplet of excited charmed baryons decaying to lambda+c pi.

We report the observation of an isotriplet of excited charmed baryons, decaying into Lambda(+)(c)pi(-), Lambda(+)(c)pi(0), and Lambda(+)(c)pi(+). We measure the mass differences M(Lambda(+)(c)pi)-M(Lambda(+)(c)) and widths to be 515.4(+3.2+2.1)(-3.1-6.0) MeV/c(2), 61(+18+22)(-13-13) MeV for the neutral state; 505.4(+5.8+12.4)(-4.6-2.0) MeV/c(2), 62(+37+52)(-23-38) MeV for the charged state; and 514.5(+3.4+2.8)(-3.1-4.9) MeV/c(2), 75(+18+12)(-13-11) MeV for the doubly charged state, where the uncertainties are statistical and systematic, respectively. These results are obtained from a 281 fb(-1) data sample collected with the Belle detector near the Upsilon(4S) resonance, at the KEKB asymmetric energy e(+)e(-) collider.

Journal Article↗
PubMed2005

Search for D0-D0 mixing in D0 --> K+ pi(-) decays and measurement of the doubly-Cabibbo-suppressed decay rate.

We have searched for mixing in the D(0)-D (0) system by measuring the decay-time distribution of D(0) --> K(+) pi(-) decays. The analysis uses 90 fb(-1) of data collected by the Belle detector at the KEKB e(+) e(-) collider. We fit the decay-time distribution for the mixing parameters x' and y' and also for the parameter R(D), which is the ratio of the rate for the doubly-Cabibbo-suppressed decay D(0)--> K+ pi(-) to that for the Cabibbo-favored decay D(0)--> K-pi(+). We do these fits both assuming CP conservation and allowing for CP violation. We use a frequentist method to obtain a 95% C.L. region in the x'(2) - y' plane. Assuming no mixing, we measure R(D) = (0.381 +/- 0.017(+0.008)(-0.016))%.

Journal Article↗
PubMed2005

Observation of B0-->D*sJ(2317)+K- decay.

The decays B0-->D+sJK- and B0-->D-sJpi+ are studied for the first time. A significant signal is observed in the B0-->D*sJ(2317)+K- decay channel with B(B0-->D*sJ(2317)+K-) x B(D*sJ(2317)+-->D+spi0)=(5.3(+1.5)(-1.3)+/-0.7+/-1.4) x 10(-5). No signals are observed in the B0-->D*sJ(2317)-pi+, B0-->DsJ(2460)+K-, and B 0-->DsJ(2460)-pi+ decay modes, and upper limits are obtained. The analysis is based on a data set of 140 fb(-1) collected by the Belle experiment at the asymmetric e+e- collider KEKB.

Journal Article↗
PubMed2005

Measurement of the branching fraction and CP asymmetry in B+ --> rho+pi0.

We report a measurement of the branching fraction for the decay B+ --> rho(+) pi(0) based on a 140 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider. We measure the branching fraction B(B(+) --> rho(+)pi(0)) = (13.2 +/- 2.3(stat)(+1.4)(-1.9)(syst)) x 10(-6), and the CP-violating asymmetry A(CP)(B-/+ -->rho(-/+)pi(0))=0.06 +/- 0.17(stat)(+0.04)(-0.05)(syst).

Journal Article↗
PubMed2005

Role of cumulus cells during maturation of porcine oocytes in the rise in intracellular Ca2+ induced by inositol 1,4,5-trisphosphate.

At the time of fertilization, release of inositol 1,4,5-trisphosphate (IP3) into the cytoplasm of oocytes is said to be induced by hydrolysis of phosphatidylinositol bis phosphate (PI2) via activation of phospholipase C and is responsible for the Ca2+ oscillation in oocytes immediately after sperm penetration. On the other hand, cumulus cells have been reported to play an important role in cytoplasmic maturation of mammalian oocytes and to affect embryonic development after fertilization. To obtain more information on the role of cumulus cells in cytoplasmic maturation of oocytes, the effects of cumulus cells on the rise in [Ca2+]i and the rates of activation and development of porcine mature oocytes induced by IP3 injection were investigated. Mature porcine oocytes that had been denuded of their cumulus cells in the early stage of the maturation period had a depressed rise in [Ca2+]i (4.0-6.0) and reduced rates of activation (31.4-36.8%) and development (10.0-24.4%) induced by IP3 injection compared with those of their cumulus-enclosed counterparts (7.3, 69.1% and 43.8%; P < 0.05). The [Ca2+]i rise and the rates of activation and development depressed by the removal of cumulus cells were restored by adding pyruvate to the maturation medium. Furthermore, the IP3 injection-induced depression of [Ca2+]i rise in mature oocytes derived from cumulus-denuded oocytes (DOs) was restored when they were cultured in a medium with pyruvate (3.9-6.3, P < 0.05). Also, mature oocytes from cumulus-oocyte complexes (COCs) cultured in a medium without glucose had a lower rise in [Ca2+]i than that in mature oocytes from COCs cultured with glucose (7.4-6.0, P < 0.05). Cumulus cells supported porcine oocytes during maturation in the rise in [Ca2+]i induced by IP3 and the following activation and development of porcine oocytes after injection of IP3. Moreover, we inferred that a function of cumulus cells is to produce pyruvate by metabolizing glucose and to provide oocytes with pyruvate during maturation, thereby promoting oocyte sensitivity to IP3.

Animals↗
PubMed2005

Experimental model for investigating hyponatremia after subarachnoid hemorrhage in rats.

Hyponatremia is a common complication in patients with aneurysmal subarachnoid hemorrhage (SAH). Such patient demonstrates excessive natriuresis and an increased risk of symptomatic cerebral vasospasm. However, the precise mechanisms underlying SAH induced hyponatremia remain unclear. In the present study, in order to establish an experimental model of hyponatremia following SAH, we induced SAH in rats, and evaluated the serum sodium (Na) levels, Na excretion and physiological parameters. Twenty-four male Wistar rats were used. SAH was induced by an endovascular puncture method. The mean arterial pressure (MAP), intracranial pressure (ICP), and cerebral blood flow (CBF) were monitored continuously. The urine was collected cumulatively for 12 hours after SAH, and the urine Na concentration was determined with a spectrophotometer. The serum Na levels were measured at 12 hrs, 2 and 4 days following the SAH induction. The mean (+/- standard deviation) baseline ICP was 3.5 +/- 2.6 mmHg, and increased to 67.4 +/- 17.6 mmHg immediately following induction of SAH. CBF decreased rapidly, and then gradually recovered to 70-80% of baseline. The urine volume and total Na excretion were significantly increased in comparison to those of the sham (P < 0.05). The serum Na level was significantly decreased at 4 days following SAH (P < 0.05). The present results demonstrated for the first time that rats with SAH exhibited excessive natriuresis. The endovascular puncture model is suitable for investigating hyponatremia that occurs concomitantly with natriuresis and diuresis after SAH.

Animals↗
PubMed2005

Differential apoptotic pathways in human keratinocyte HaCaT cells exposed to UVB and UVC.

The induction of apoptosis in keratinocytes by ultraviolet (UV)-irradiation is considered to be a protective function against skin cancer. UV-induced DNA damage is a crucial event in UVB- and UVC-mediated apoptosis. However, the differences between the UVB- and UVC-induced apoptotic pathways remain unclear. Here we examine the differential mechanisms by which UVB and UVC irradiations induce keratinocyte apoptosis using human keratinocyte HaCaT cells. Differences in the production of (6-4)photoproducts ((6-4)PPs) and cyclobutane pyrimidine dimers (CPDs) were measured following irradiation with UVB and UVC at doses causing the same extent of apoptotic cell death. In addition, main apoptotic features, such as caspase activation and its regulation, were compared between UVB- and UVC-induced apoptosis. Exposures of 500 J/m(2) UVB and 100 J/m(2) UVC resulted in apoptosis to almost the same extent. At these apoptotic doses, the amounts of both (6-4)PPs and CPDs were significantly larger in the case of UVC irradiation than UVB irradiation; in parallel, the release of cytochrome c and Smac/DIABLO and the activation of caspases-9 following UVC irradiation were greater than after UVB irradiation. Importantly, caspase-8 activation occurred only in UVB-irradiated cells. Furthermore, the activation of caspase-8 was not inhibited by caspases-9 and -3 specific tetrapeptide inhibitors, indicating that the caspase-8 cleavage is not due to feedback from activation of caspases-9 and -3. Thus, these results clearly suggest that the reason apoptosis is induced to the same extent by UVB irradiation as by UVC irradiation, despite the lower production of photoproducts in DNA by UVB irradiation, is attributable to the additional activation of the caspase-8 pathway. Thus, UVB irradiation induces apoptosis through both mitochondrial (intrinsic) and caspase-8 activation (extrinsic) pathways, while UVC induces apoptosis only via the intrinsic pathway.

Apoptosis↗
PubMed2005

Reduced-intensity hematopoietic stem-cell transplantation for malignant lymphoma: a retrospective survey of 112 adult patients in Japan.

We conducted a nation-wide survey of 112 adult Japanese patients who underwent reduced-intensity stem cell transplantation (RIST) from 1999 to 2002. Underlying diseases included indolent (n=45), aggressive (n=58) and highly aggressive lymphomas (n=9). Median age of the patients was 49 years. A total of 40 patients (36%) had relapsed diseases after autologous stem cell transplantation and 36 patients (32%) had received radiotherapy. RIST regimens were fludarabine-based (n=95), low-dose total body irradiation-based (n=6) and others (n=11). Cumulative incidences of grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD were, respectively, 49 and 59%. Cumulative incidences of progression and progression-free mortality were 18 and 25%, respectively. With a median follow-up of 23.9 months, 3-year overall survival rates were 59%. A multivariate analysis identified three significant factors for progression, which are history of radiation (relative risk (RR) 3.45, confidential interval (CI) 1.12-10.0, P=0.03), central nervous system involvement (RR 6.25, CI 2.08-20.0, P=0.001) and development of GVHD (RR 0.28, CI 0.090-0.86, P=0.026). RIST may have decreased the rate of transplant-related mortality, and GVHD may have induced a graft-versus-lymphoma effect. However, whether or not these potential benefits can be directly translated into improved patient survival should be evaluated in further studies.

Adult↗
PubMed2005

Zonal necrosis prevented by transduction of the artificial anti-death FNK protein.

Protection of cells from necrosis would be important for many medical applications. Here, we show protein transduction domain (PTD)-FNK therapeutics based on protein transduction to prevent necrosis and acute hepatic injury with zonal death induced by carbon tetrachloride (CCl4). PTD-FNK is a fusion protein comprising the HIV/Tat PTD and FNK, a gain-of-function mutant of anti-apoptotic Bcl-x(L). PTD-FNK protected hepatoma HepG2 from necrotic death induced by CCl4, and additionally, increased the apoptotic population among cells treated with CCl4. A concomitant treatment with a pan-caspase inhibitor Z-VAD-FMK (N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone), which alone could not prevent the necrosis, protected these cells from the apoptosis. When pre-injected intraperitoneally, PTD-FNK markedly reduced zonal liver necrosis caused by CCl4. Moreover, injection of PTD-FNK accompanied by Z-VAD-FMK suppressed necrotic injury even after CCl4 administration. These results suggest that PTD-FNK has great potential for clinical applications to prevent cell death, whether from apoptosis or necrosis, and organ failure.

Adenosine Triphosphate↗
PubMed2005

Identification of human T cell epitopes in Japanese cypress pollen allergen, Cha o 1, elucidates the intrinsic mechanism of cross-allergenicity between Cha o 1 and Cry j 1, the major allergen of Japanese cedar pollen, at the T cell level.

BACKGROUND: Pollens from species of Cupressaceae family are one of the most important causes of respiratory allergies worldwide. In Japan, many patients with pollinosis have specific IgE to both pollens of Japanese cypress (Chamaecyparis obtusa) and Japanese cedar (Cryptomeria japonica). The sequences between Cha o 1 and Cry j 1, the major allergens of Japanese cypress and Japanese cedar pollens, respectively, are 80% identical. OBJECTIVE: This study was undertaken to identify T cell epitopes in Cha o 1, and to elucidate the mechanism of cross-allergenicity between Cha o 1 and Cry j 1, at the T cell level. METHODS: T cell epitopes in Cha o 1 were identified by the reactivity of T cell lines, generated from 19 patients, to stimulation with overlapping peptides. The subsets of T cell clones specific to rCha o 1 were determined according to their ability to produce IL-4 and IFN-gamma. Peptide specificities of two T cell clones were determined by stimulation with the peptides from Cha o 1 and Cry j 1. RESULTS: Four dominant and six subdominant T cell epitopes were identified in Cha o 1. While four T cell epitopes, p11-30, p211-230, p251-270 and p331-350, were common to Cha o 1 and Cry j 1, 4 T cell epitopes, p61-80, p71-90, p311-330 and p321-340, were considered to be unique to Cha o 1. The subsets of T cell clones were predominantly of T helper2-type. One T cell clone recognized p16-30, which is common to Cha o 1 and Cry j 1, but another recognized p321-330, which is unique to Cha o 1. CONCLUSION: Presence of both T cells reactive to T cell epitopes common to Cha o 1 and Cry j 1 and T cells specific to T cell epitopes unique to Cha o 1 in patients with pollinosis contributes to prolonged symptoms after the cedar pollen season in March and the following cypress pollen season in April.

Adult↗
PubMed2005

Comparison between partial agonist (ME3412) and antagonist (alosetron) of 5-hydroxytryptamine 3 receptor on gastrointestinal function.

Therapeutic use of 5-hydroxytryptamine 3 (5-HT(3)) receptor antagonists for diarrhoea-predominant irritable bowel syndrome may be accompanied by constipation. We hypothesized that ME3412, 5-chloro-2-(1,4-diazacycloheptan-1-yl)-7-methylbenzoxazole, a novel partial agonist of the 5-HT(3) receptor, would minimize constipation without reducing antidiarrhoeal activity. Receptor binding studies showed that ME3412 is highly selective for the human 5-HT(3) receptor (K(i) = 1.51 nmol L(-1)). A 5-HT(3) receptor agonist, 2-methyl-5-HT, caused contractile response in the isolated guinea-pig ileum and accelerated secretion in the guinea-pig colonic mucosal preparation. ME3412 and 5-HT(3) receptor antagonist, alosetron, antagonized the 2-methyl-5-HT-induced responses with similar potency in insurmountable and surmountable manner, respectively. ME3412 caused weak agonism in isolated ileum strips and also in the colonic mucosa with intrinsic activity of 0.09 and 0.59, respectively. In conscious dogs, alosetron (3 microg kg(-1) i.v.) suppressed the migrating motor complex (MMC), whereas a relatively high dose (300 microg kg(-1)) of ME3412 was required for inhibition of MMC. ME3412 and alosetron suppressed 5-HT induced-diarrhoea in mice. In contrast, ME3412 did not significantly affect colonic propulsion compared with alosetron. These results imply that the partial agonist may relieve diarrhoea with low risk of inducing constipation.

Animals↗
PubMed2005

Collagenofibrotic glomerulonephropathy in a cynomolgus macaque (Macaca fascicularis).

Collagenofibrotic glomerulonephropathy (CFGN) is characterized by the deposition of type III collagen within the mesangial matrix and the absence of mesangial cell proliferation. A case of CFGN in a 2.7-year-old female cynomolgus macaque was investigated in the present study. Clinically, the animal was shown to have severe systemic edema along with hypoproteinemia. At necropsy, the kidneys were swollen and pale. The glomerular lesions were characterized by massive diffuse and global accumulation of fibrous materials in the mesangial areas. Neither mesangial cell proliferation nor changes in other organs were found. The fibrous materials were confirmed by the results of immunohistochemical and electron microscopic findings to consist mainly of randomly arranged, curve-shaped, twisted, and entwined type III collagen. This is the first case report of CFGN in nonhuman primates to date.

Animals↗
PubMed2005

Arundic acid (ONO-2506) ameliorates delayed ischemic brain damage by preventing astrocytic overproduction of S100B.

After focal cerebral ischemia, the infarct volume increases rapidly within acute infarct expansion (initial 12 to 24 h) and continues slowly during delayed infarct expansion (25 to 168 h). While acute infarct expansion represents progressive necrosis within the ischemic core, delayed infarct expansion starts as disseminated apoptotic cell death in a narrow rim surrounding the infarct border, which gradually coalesces to form a larger infarct. Discovery of a distinct correlation between reactive astrogliosis along the infarct border and delayed infarct expansion in the rodent ischemia model led us to investigate the possible causal relationship between the two events. Specifically, the calcium binding protein S100B exerts detrimental effects on cell survival through activation of various intracellular signaling pathways, resulting in altered protein expression. Arundic acid [(R)-(-)-2-propyloctanoic acid, ONO-2506] is a novel agent that inhibits S100B synthesis in cultured astrocytes. In the rodent ischemia model, this agent was shown to inhibit both the astrocytic overexpression of S100B and the subsequent activation of signaling pathways in the peri-infarct area. Concurrently, delayed infarct expansion was prevented, and neurologic deficits were promptly ameliorated. The results of subsequent studies suggest that the efficacy of arundic acid is mediated by restoring the activity of astroglial glutamate transporters via enhanced genetic expression.

Animals↗
PubMed2005

Development of endometrial cancer following radiation therapy for cervical carcinoma.

The clinical and histologic findings in five cases of endometrial cancer, which developed following radiation therapy for squamous cell carcinoma of the cervix, are described. The mean age at endometrial cancer diagnosis was 69 years and average latency period from initial therapy to development of endometrial carcinoma was 13.4 years. For endometrial cancer, one patient had Stage Ib, one patient had Stage IIIa, two patients had Stage IIIc, and one patient did not undergo laparotomy. The histological types were carcinosarcoma in two patients, endometrioid adenocarcinoma, grade 3 in one patient, and clear cell carcinoma in one patient. All patients died of disease within 33 months of diagnosis. Endometrial cancers that develop after radiation treatment have a preponderance of high-risk histological subtypes, and consequently have a poor prognosis. Long-term follow-up should be mandatory for patients surviving radiation therapy for cervical cancer in order to detect and effectively treat second malignancies.

Adenocarcinoma↗