55 research outputs found
Calpain-dependent disruption of nucleo-cytoplasmic transport in ALS motor neurons
Nuclear dysfunction in motor neurons has been hypothesized to be a principal cause of amyotrophic lateral sclerosis (ALS) pathogenesis. Here, we investigated the mechanism by which the nuclear pore complex (NPC) is disrupted in dying motor neurons in a mechanistic ALS mouse model (adenosine deaminase acting on RNA 2 (ADAR2) conditional knockout (AR2) mice) and in ALS patients. We showed that nucleoporins (Nups) that constituted the NPC were cleaved by activated calpain via a Ca2+-permeable AMPA receptor-mediated mechanism in dying motor neurons lacking ADAR2 expression in AR2 mice. In these neurons, nucleo-cytoplasmic transport was disrupted, and the level of the transcript elongation enzyme RNA polymerase II phosphorylated at Ser2 was significantly decreased. Analogous changes were observed in motor neurons lacking ADAR2 immunoreactivity in sporadic ALS patients. Therefore, calpain-dependent NPC disruption may participate in ALS pathogenesis, and inhibiting Ca2+-mediated cell death signals may be a therapeutic strategy for ALS.UTokyo Research掲載「核と細胞質間の分子輸送経路の破綻が筋萎縮性側索硬化症に関与」 URI: http://www.u-tokyo.ac.jp/ja/utokyo-research/research-news/disruption-of-molecule-transport-pathway-between-nucleus-and-cytoplasm-involved-in-als.htmlUTokyo Research "Disruption of molecule transport pathway between nucleus and cytoplasm involved in ALS" URI: http://www.u-tokyo.ac.jp/en/utokyo-research/research-news/disruption-of-molecule-transport-pathway-between-nucleus-and-cytoplasm-involved-in-als.htm
Intraluminal implantation of rectal carcinoma successfully resected by endoscopy.
A 55-year-old Japanese woman presented at our hospital complaining of hematochezia 4 months after surgery for a rectal carcinoma. A proctoscopy revealed 2 protuberant lesions in the rectum, 5 mm anally from the anastomotic suture line. The diagnosis of adenocarcinoma was confirmed by biopsy. It was considered that these lesions were caused by intraluminal implantation from the primary rectal carcinoma. The patient underwent an endoscopic resection for these recurrent lesions and has remained stable, with neither recurrence nor metastasis, in the 7 years since the resection. For rectal carcinoma, we propose early follow-up by proctoscopy, namely within 4 months after surgery.</p
Search for B^0-> p p-bar, Lambda Lambda-bar and B^+ -> p Lambda-bar at Belle
We report on a new search for two-body baryonic decays of the B meson.
Improved sensitivity compared to previous Belle results is obtained from 414
fb^-1 of data that corresponds to 449 million B B-bar pairs, which were taken
on the Upsilon(4S) resonance and collected with the Belle detector at the KEKB
e^+e^- collider. No significant signals are observed and we set the 90%
confidence level upper limits: Br(B^0-> p pbar) Lambda
Lambda-bar) p Lambda-bar) < 3.2X10^-7.Comment: 5 pages, 2 figures, submitted to PR
Measurement of D0 -> pilnu (Klnu) Form Factors and Absolute Branching Fractions
Using a 282 1/fb data sample collected by the Belle experiment at the KEKB
e+e- collider, we study D0 decays to K-l+nu and pi-l+nu final states. The D0
flavor and momentum are tagged through a full reconstruction of the recoiling
charm meson and additional mesons from fragmentation. The reconstruction method
provides very good resolution in neutrino momentum and in q^2 = (p_l+p_nu)^2.
Normalizing to the total number of D0 tags, we measure the absolute branching
fractions to be B(D0 -> Klnu) =(3.45 +- 0.07stat +- 0.20syst)% and B(D0 ->
pilnu) = (0.255 +- 0.019stat +- 0.016syst)% and the semi-leptonic form factors
(within the modified pole model) f+^K(0) = 0.695 +- 0.007stat +- 0.022syst and
f+^pi(0) = 0.624 +- 0.020stat +- 0.030syst.Comment: 9 pages, 2 figures, submitted to Phys. Rev. Let
Improved Measurements of Branching Fractions and CP Asymmetries in B-> eta h Decays
We report improved measurements of B decays with an eta meson in the final
state using 492 fb^{-1} of data collected by the Belle detector at the KEKB e^+
e^- collider. We observe the decays B^{+-}-> eta pi^{+-} and B^{+-}-> eta
K^{+-}; the measured branching fractions are Br(B^{+-}-> eta pi^{+-}) = (4.2+-
0.4(stat)+- 0.2(sys))x10^{-6} and Br(B^{+-}-> eta K^{+-}) =
(1.9+-0.3(stat)^{+0.2}_{-0.1}(sys))x10^{-6}. The corresponding CP-violating
asymmetries are measured to be -0.23+- 0.09(stat) +-0.02(sys) for eta pi^{+-}
and -0.39+-0.16(stat)+-0.03(sys) for eta K^{+-}. We also search for B^0-> eta
K^0 decays and set an upper limit of 1.9x10^{-6} at the 90% confidence level.Comment: 7 pages, 3 figure
Measurement of Azimuthal Asymmetries in Inclusive Production of Hadron Pairs in e+e- Annihilation at Belle
The Collins effect connects transverse quark spin with a measurable azimuthal
dependence in the yield of hadronic fragments around the quark's momentum
vector. Using two different reconstruction methods we observe statistically
significant azimuthal asymmetries for charged pion pairs in e+e- annihilation
at a center-of-mass energy of 10.52 GeV, which can be attributed to a
transverse polarization of the primordial quarks. The measurement was performed
using a sample of 79 million hadronic events collected with the Belle detector.Comment: 6 pages, 4 figure
Measurement of phi_3 with Dalitz plot analysis of B+ -> D(*)K(*)+ decay
We present a measurement of the unitarity triangle angle phi_3 using a Dalitz
plot analysis of the K0_S pi+ pi- decay of the neutral D meson from the B+- ->
D(*)K(*)+- process. The method employs the interference between D0 and D0bar to
extract the angle phi_3, strong phase Delta and the ratio r of suppressed and
allowed amplitudes. We apply this method to a 357 fb-1 data sample collected by
the Belle experiment. The analysis uses three modes: B+ -> DK+, B+ -> D*K+ with
D* -> Dpi0, and B+ -> DK*+ with K*+ -> K0_S pi+, as well as the corresponding
charge-conjugate modes. From a combined maximum likelihood fit to the three
modes, we obtain phi_3=53+15-18(stat)+-3(syst)+-9(model) degrees. The
corresponding two standard deviation interval is 8<phi_3<111 degrees.Comment: 18 pages, 6 figures, 7 tables. To be submitted to Phys. Rev.
Observation of a new charmonium state in double charmonium production in e+ e- annihilation at \sqrt{s} ~ 10.6 GeV
We report the first observation of a new charmonium state at a mass of
. This state, called X(3940), is
observed in the process in the spectrum of masses
recoiling against a reconstructed . We also observe the decay of the
X(3940) into and measure the intrinsic width of this state to be
less than at the 90% C.L. These results are obtained from a data sample collected with the Belle detector near the
resonance, at the KEKB asymmetric energy collider.Comment: BELLE-CONF-051
Search for B+ -> J/psi eta' K+ and B0 -> J/psi eta' Ks0 Decays
We report the results of searches for B+ -> J/psi eta' K+ and B0 -> J/psi
eta' Ks0 decays, using a sample of 388 x 10^6 BBbar pairs collected with the
Belle detector at the Upsilon(4S) resonance. No statistically significant
signal is found for either of the two decay modes and upper limits for the
branching fractions are determined to be B(B+ -> J/psi eta' K+) < 8.8 x 10^-5
and B(B0 -> J/psi eta' Ks0) < 2.5 x 10^-5 at 90% confidence level.Comment: 5 pages, 6 figures, submitted to PRD Brief Repor
Dalitz Analysis of Three-body Charmless B0=>K0pi+pi- Decay
We report results of a Dalitz plot analysis of the three-body charmless
B0=>K0pi+pi- decay. The analysis is performed with a data sample that contains
388 million BBbar pairs collected near the Y(4S) resonance with the Belle
detector at the KEKB asymmetric energy e+e- collider. Measurements of branching
fractions for the quasi-two-body decays B0=>rho(770)0K0, B0=>f0(980)K0,
B0=>K*(892)+pi-, B0=>K*(1430)+pi-, and upper limits on several other
quasi-two-body decay modes are reported.Comment: 9 pages, 5 figures. Submitted to Phys. Rev. Let
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