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Y Kuno

Publications and source records attributed to Y Kuno.

At least 19 recordsLinked to original sources
PubMed2006

Improved search for nu(mu) --> nu(e) oscillation in a long-baseline accelerator experiment.

We performed an improved search for nu(mu) --> nu(e) oscillation with the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment, using the full data sample of 9.2 x 10(19) protons on target. No evidence for a nu(e) appearance signal was found, and we set bounds on the nu(mu) --> nu(e) oscillation parameters. At Deltam(2)=2.8 x 10(-3) eV(2), the best-fit value of the K2Knu(mu) disappearance analysis, we set an upper limit of sin(2)2theta(mue) < 0.13 at a 90% confidence level.

Journal Article↗
PubMed2005

Search for coherent charged pion production in neutrino-carbon interactions.

We report the result from a search for charged-current coherent pion production induced by muon neutrinos with a mean energy of 1.3 GeV. The data are collected with a fully active scintillator detector in the K2K long-baseline neutrino oscillation experiment. No evidence for coherent pion production is observed, and an upper limit of is set on the cross section ratio of coherent pion production to the total charged-current interaction at 90% confidence level. This is the first experimental limit for coherent charged pion production in the energy region of a few GeV.

Journal Article↗
PubMed2005

Evidence for muon neutrino oscillation in an accelerator-based experiment.

We present results for nu(mu) oscillation in the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment. K2K uses an accelerator-produced nu(mu) beam with a mean energy of 1.3 GeV directed at the Super-Kamiokande detector. We observed the energy-dependent disappearance of nu(mu), which we presume have oscillated to nu(tau). The probability that we would observe these results if there is no neutrino oscillation is 0.0050% (4.0 sigma).

Journal Article↗
PubMed2005

Audit of the use of psoralen photochemotherapy (PUVA) and narrowband UVB phototherapy in the treatment of psoriasis.

BACKGROUND: Psoralen photochemotherapy (PUVA), the combined use of psoralen and long wave ultraviolet (UVA) irradiation, was introduced around 1974 and its beneficial effects were rapidly confirmed worldwide. In an attempt to minimize its recognized long-term photocarcinogenic risk after some 150-200 exposures while also maintaining efficacy, however, the narrowband (311-312 nm) ultraviolet B (UVB) lamp (TL-01) was introduced in 1984, and has moved towards replacing PUVA except for severe or resistant disease. AIMS: To discover whether our use of these therapies complied with established British Photodermatology Group guidelines for PUVA and guidelines formulated within our unit for narrowband UVB. METHODS: The study was retrospective over 6 months from November 2001 to April 2002, all relevant information being obtained from the patients' hospital notes. RESULTS: Thirty-one patients received PUVA (18 oral, 11 bath and two uncertain because of missing notes) and 20 narrowband UVB during this period. CONCLUSIONS: Our PUVA and narrowband UVB phototherapy guidelines were shown to have been followed relatively closely with the following exceptions: one PUVA patient received a high cumulative exposure by mutual agreement because there was no other suitable therapy; a failure to measure minimal phototoxic doses (MPDs) in some PUVA patients; and slightly prolonged referral delays, but generally by patient choice.

Female↗
PubMed2004

New procedure for purse-string suture in thoracoscopic esophagectomy with intrathoracic anastomosis.

BACKGROUND: In endoscopic surgery, one of the greatest problems is the difficulty with the reconstructive procedure. This problem frequently makes operating times longer. The authors have performed thoracoscopic esophagectomy and intrathoracic esophagogastric anastomosis for reconstruction using a circular stapler for the esophageal cancer. Although the circular stapler is a useful device for gastrointestinal anastomosis, it was difficult to place a purse-string suture and to fixate the anvil into the proximal esophagus endoscopically. METHODS: The authors devised a new procedure for the placement of the purse-string suture by using an Endo-Stitch device along with a new method to incise the esophageal wall and thereby facilitate fixation of the anvil. RESULTS: The authors attempted this procedure for five patients. The anastomoses were performed successfully. CONCLUSIONS: The new procedure can make endoscopic intrathoracic anastomosis feasible and safe. In addition, this procedure can be applied widely to other endoscopic reconstructions.

Anastomosis, Surgical↗
PubMed2004

New limit on the T-violating transverse muon polarization in K+-->pi0mu+nu decays.

A search for T-violating transverse muon polarization (P(T)) in the K+-->pi(0)mu(+)nu decay was performed using kaon decays at rest. A new improved value P(T)=-0.0017+/-0.0023(stat)+/-0.0011(syst) was obtained giving an upper limit |P(T)|<0.0050. The T-violation parameter was determined to be Imxi=-0.0053+/-0.0071(stat)+/-0.0036(syst) giving an upper limit |Imxi|<0.016.

Journal Article↗
PubMed2004

TEL-Syk fusion constitutively activates PI3-K/Akt, MAPK and JAK2-independent STAT5 signal pathways.

We previously reported the fusion of the TEL gene to the Syk gene in myelodysplastic syndrome with t(9;12)(q22;p12). TEL-Syk fusion transformed interleukin-3 (IL-3)-dependent murine hematopoietic cell line BaF3 to growth factor independence. Here, we investigate the intracellular signal transduction of the stable transfectants. TEL-Syk fusion protein was associated with the p85 subunit of phosphatidyl inositol 3 kinase (PI3-K) followed by the activation of Akt in the absence of IL-3. Vav, phospholipase C-gamma2 and mitogen-activated protein kinase (MAPK) were also constitutively activated. TEL-Syk also activated the signal transducer and activator of transcription 5 (STAT5) in the absence of Janus kinase 2 activation. None of these kinases were phosphorylated in the BaF3 cells transfected with TELDeltaPNT-Syk in which the oligomerization domain of TEL was deleted. Inhibitor analysis showed that the MAPK pathway was important in TEL-Syk-mediated cell proliferation. The immunofluorescence technique revealed that the TEL-Syk fusion protein was located in the cytoplasm. These data suggest that TEL-Syk fusion protein in the cytoplasm leads to the constitutive activation of PI3-K/Akt, MAPK and STAT5 signal pathways, which are closely involved in IL-3-independent cell proliferation of BaF3 cells.

Amino Acid Substitution↗
PubMed2002

Further evidence for the decay K+ -->pi+nu(nu).

Additional evidence for the rare kaon decay K+-->pi+nu(nu) has been found in a new data set with comparable sensitivity to the previously reported result. One new event was observed in the pion momentum region examined, 211 pi+nu(nu)) = 1.57(+1.75)(-0.82)x10(-10).

Journal Article↗
PubMed2001

Constitutive kinase activation of the TEL-Syk fusion gene in myelodysplastic syndrome with t(9;12)(q22;p12).

The TEL gene on 12p12-13 is a target for a number of translocations associated with various hematological malignancies. The fusion of the TEL gene to the Syk gene in a patient with myelodysplastic syndrome (MDS) with t(9;12)(q22;p12) is reported. Southern blot analysis of patient bone marrow cells with TEL and Syk gene probes detected rearranged fragments. Anchored polymerase chain reaction identified the Syk gene, a nonreceptor tyrosine kinase, on 9q22 fused downstream of TEL exon 5. The TEL gene was fused in-frame to Syk and produced a fusion protein that was constitutively phosphorylated in tyrosine with dimerization that was mediated by the helix-loop-helix domain of TEL. A TEL-Syk fusion product transformed the murine hematopoietic cell line BaF3 to interleukin-3 growth factor independence. TEL-Syk is a novel transforming protein and leads to the transformation of hematopoietic cells. These data implicate that the rearranged Syk gene is involved in the pathogenesis of hematopoietic malignancies.

Amino Acid Sequence↗
PubMed2000

Measurement of direct photon emission in K+-->pi(+)pi(0)gamma decay

We have performed a measurement of the K+-->pi(+)pi(0)gamma decay and have observed 2x10(4) events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7+/-0.8+/-0. 3)x10(-6) in the pi(+) kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung.

Journal Article↗
PubMed2000

Measurement of structure-dependent K+ --> &mgr;(+)nu(&mgr;)gamma decay

We report the first measurement of a structure-dependent component in the decay K+-->&mgr;(+)nu(&mgr;)gamma. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is |F(V)+F(A)| = 0.165+/-0.007+/-0.011. This corresponds to a branching ratio of B(SD+) = (1.33+/-0.12+/-0.18)x10(-5). We also set the limit -0. 04<F(V)-F(A)<0.24 at 90% C.L.

Journal Article↗
PubMed2000

Different mechanisms between premitotic apoptosis and postmitotic apoptosis in X-irradiated U937 cells.

PURPOSE: Apoptosis is currently being evaluated for its importance as a pathway of radiation-induced cell death. However, the difference in the mechanisms between premitotic and postmitotic apoptosis following X-irradiation remains not well understood. We show here that the human monoblastoid cell line U937 can be induced to undergo these two different types of apoptosis. METHODS AND MATERIALS: U937 cells were irradiated at a dose of 5 or 20 Gy, and the DNA fragmentation rate was measured by both flow cytometric analysis and gel electrophoresis. Activation of caspase-3 was detected by Western blot analysis and fluorogenic assay using acetyl-Asp-Glu-Val-Asp-7-amino-4-methyl-coumarin (Ac-DEVD-AMC). Detection of mitochondrial transmembrane potential (DeltaPsi) was performed by using Rho123. Chasing of S-phase fraction following X-irradiation was performed after labeling with 5-bromo-2'-deoxyuridine (BrdU). Thymidine was used for synchronization of the cells. Inhibition of caspase-3 activity was achieved by Acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO). RESULTS: Time courses of the apoptotic rates, caspase activation, and DeltaPsi indicated that two different types of cell death were induced by the different X-ray doses. High-dose X-ray (20 Gy) induced a rapid and strong apoptosis, whereas low-dose X-ray (5 Gy) induced a slow and mild apoptosis. Cell-cycle analyses revealed that there was cell death before cell division in the former apoptosis but the cells must be dying after cell division in the latter apoptosis. By means of cell-cycle synchronization, the S-phase cells proved to be the most sensitive fraction to premitotic apoptosis, but an obvious difference in the susceptibility to cell death among the cell-cycle phases was not observed in postmitotic apoptosis. Ac-DEVD-CHO treatment effectively blocked caspase activity and premitotic apoptosis, but it failed to block postmitotic apoptosis. CONCLUSIONS: Irradiation of U937 cells at different X-ray doses induced two different types of apoptotic cell death, premitotic apoptosis and postmitotic apoptosis, which are characterized by the time course and cell-cycle specificity. Decision concerning these two types of apoptotic cell death may be made by the difference in the magnitude of cell damage following X-irradiation.

Apoptosis↗
PubMed2000

Further search for the decay K+-->pi(+)nunu;

A search for additional evidence for the rare kaon decay K+-->pi(+)nunu; has been made with a new data set comparable in sensitivity to the previous exposure that produced a single event. No new events were found in the pion momentum region examined, 211 pi(+)nunu;) = 1.5(+3.4)(-1.2)x10(-10).

Journal Article↗
PubMed2000

PR-000350, a novel hypoxic radiosensitizer, enhances tumor cell killing by promoting apoptosis preferentially in the S-phase fraction.

PR-000350, a novel hypoxic radiosensitizer, is a 2-nitroimidazole nucleoside analog and has begun to be used for clinical cancer therapy. In this study, using U937 monoblastoid cells we investigated the mechanisms of enhanced cell killing by PR-000350. When cells were irradiated under an extremely hypoxic condition, the apoptotic rate was strongly suppressed. However, a remarkable increase in the DNA fragmentation rate as well as in the ladder formation was observed when hypoxic cells were irradiated in the presence of 5 mM PR-000350. DNA histograms of the PR-000350 treated group showed enhancement of the sub-G1 fraction and simultaneous suppression of the progression of the cell cycle from the S to G2/M phase at 4-8 h after X-irradiation, suggesting the importance of the S phase in the induction of apoptotic cell death. Flow cytometric and immunohistochemical analyses after BrdU labelling revealed that apoptotic cell death is induced mainly in the BrdU-positive cells. In addition, by using cell synchronization technique it was proved that the S phase is the most sensitive fraction to the radiosensitizing effect of PR-000350. These results suggest that PR-000350 strongly enhances tumor cell killing by promoting X-ray induced-apoptosis preferentially in the S-phase fraction. PR-000350 is a new type radiosensitizer and promise to provide an effective anti-cancer activity against hypoxic tumor cells that are resistant to the usual radiotherapy.

Anaerobiosis↗
PubMed2000

A case of actinic prurigo showing hypersensitivity of skin fibroblasts to ultraviolet A (UVA).

We here report a patient with actinic prurigo. He had had erythematous papulovesicular eruptions on the sun-exposed sites from fall to early summer for 4 years. The lesions healed leaving atrophic scars. The histology showed epidermal necrosis and dermal dense perivascular lymphohistiocytic infiltration and edema. His minimal erythema doses to ultraviolet B (UVB) and UVA were normal and lowered, respectively. Skin lesions were produced by repeated irradiation with UVA plus UVB, but not with UVA alone. Then he was diagnosed as having actinic prurigo. Skin fibroblasts from the patient were hypersensitive to UVA. We believe that the hypersensitivity relates to the pathomechanisms of the photosensitivity in the case. UVA sensitivity of fibroblasts may be useful for differentiating actinic prurigo, hydroa vacciniforme, and other similar photosensitive disorders.

Adult↗
PubMed2000

Mucoadhesive DL-lactide/glycolide copolymer nanospheres coated with chitosan to improve oral delivery of elcatonin.

The purpose of this work was to develop a novel mucoadhesive DL-lactide/glycolide copolymer (PLGA) nanosphere system to improve peptide absorption and prolong the physiological activity following oral administration. The desired PLGA nanospheres with elcatonin were prepared by the emulsion solvent diffusion method to coat the surface of the resultant nanospheres with a mucoadhesive polymer such as chitosan, poly(acrylic acid), and sodium alginate. Their mucoadhesive properties were evaluated by measuring the nanospheres adsorbed to a rat everted intestinal sac (in vitro). The chitosan-coated nanospheres showed higher mucoadhesion to the everted intestinal tract in saline than the other polymer-coated nanospheres. There was no mucoadhesion site-specificity of the chitosan-coated nanospheres between duodenal, jejunal, and ileal sacs. The payload of drug in the chitosan-coated nanospheres was successfully increased by using the solvent diffusion method in oil. The pattern of drug release of the resultant nanospheres did not differ markedly from that of uncoated nanospheres. The chitosan-coated nanospheres with elcatonin were administered intragastrically to fasted Wistar rats. The chitosan-coated nanosphere reduced significantly the blood calcium level compared with elcatonin solution and uncoated nanospheres, and the reduced calcium level was sustained for a period of 48 hr. Even under nonfasting conditions, the mucoadhesion of chitosan-coated nanospheres was unaltered and the reduction in blood Ca levels was maintained satisfactorily.

Acrylic Resins↗