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K Hatanaka

Publications and source records attributed to K Hatanaka.

At least 19 recordsLinked to original sources
PubMed2006

Gamow-Teller strengths in the A = 14 multiplet: a challenge to the shell model.

A new experimental approach to the famous problem of the anomalously slow Gamow-Teller (GT) transitions in the beta decay of the A=14 multiplet is presented. The GT strength distributions to excited states in 14C and 14O were studied in high-resolution (d,2He) and (3He,t) charge-exchange reactions on 14N. No-core shell-model calculations capable of reproducing the suppression of the beta decays predict a selective excitation of Jpi=2+ states. The experimental confirmation represents a validation of the assumptions about the underlying structure of the 14N ground state wave function. However, the fragmentation of the GT strength over three 2+ final states remains a fundamental issue not explained by the present no-core shell model using a 6homega model space, suggesting possibly the need to include cluster structure in these light nuclei in a consistent way.

Journal Article↗
PubMed2006

Fine structure of the Gamow-Teller resonance in 90Nb and level density of 1+ states.

The fine structure of the Gamow-Teller resonance in a medium-heavy nucleus is observed for the first time in a high-resolution 90Zr(3He,t)90Nb experiment at the Research Center for Nuclear Physics, Osaka. Using a novel wavelet analysis technique, it is possible to extract characteristic energy scales and to quantify their relative importance for the generation of the fine structure. This method combined with the selectivity of the reaction permits an extraction of the level density of 1+ states in 90Nb.

Journal Article↗
PubMed2006

[Successful surgical management of papillary muscle rupture following acute myocardial infarction in an elderly patient].

Papillary muscle rupture is rare but catastrophic complication of acute myocardial infarction. We report a 91-year-old woman who underwent successful management of papillary muscle rupture following acute myocardial infarction. She was transferred to our hospital because of severe pulmonary edema and cardiogenic shock. Echocardiography revealed severe mitral valve regurgitation due to total rupture of anterolateral papillary muscle. After intubation, intraaortic balloon pumping (IABP) and percutaneous cardiopulmonary support (PCPS) insertion, mitral valve replacement was successfully performed. She was discharged 134 days after operation. In papillary muscle rupture deteriorating hemodynamics, early diagnosis and immediate cardiopulmonary support are required before surgical treatment. She was, to the best of our knowledge, the oldest among the reported cases of successful surgical treatment of papillary muscle rupture in Japan.

Aged, 80 and over↗
PubMed2006

[Ascending aorta to biaxillar and left femoral artery bypass].

A 68-year-old man was admitted to our hospital because of ischemia in the upper and lower extremities with rest pain. Aortography revealed complete bilateral subclavian artery occlusion and left femoral artery occlusion. We planned simultaneous revascularization of upper and lower extremities. Ascending aorta to biaxillar and left femoral artery bypass was performed. The postoperative course was uneventful and he was discharged on the 18th day after operation. This procedure was useful for patient with upper and lower limb ischemia.

Aged↗
PubMed2005

Gamow-teller strengths in proton-rich exotic nuclei deduced in the combined analysis of mirror transitions.

Isospin symmetry is expected for the T(z)=+/-1-->0 isobaric analogous transitions in isobars with mass number A, where T(z) is the z component of isospin T. Assuming this symmetry, strengths of analogous Gamow-Teller (GT) transitions within A = 50 isobars were determined from a high energy-resolution study at 0 degrees in combination with the decay Q value and lifetime from the beta decay. This method can be applied to other pf-shell nuclei and can be used to study GT strengths of astrophysical interest.

Journal Article↗
PubMed2005

Resolving the discrepancy of 135 MeV pd elastic scattering cross sections and relativistic effects.

Three precise measurements for elastic pd scattering at 135 MeV/A have been performed with the three different experimental setups. The cross sections are described well by the theoretical predictions based on modern nucleon-nucleon forces combined with three-nucleon forces. Relativistic Faddeev calculations show that relativistic effects are restricted to backward angles. This result supports the two measurements recently reported by RIKEN and contradicts the KVI data.

Journal Article↗
PubMed2005

Comparison between reduced intensity and conventional myeloablative allogeneic stem-cell transplantation in patients with hematologic malignancies aged between 50 and 59 years.

To evaluate the efficacy of reduced-intensity stem-cell transplantation (RIST), we retrospectively compared outcomes of 207 consecutive Japanese patients aged between 50 and 59 years with hematologic malignancies who received RIST (n=70) and conventional stem-cell transplantation (CST) (n=137). CST recipients received total body irradiation (TBI)-based or busulfan/cyclophosphamide-based regimens. RIST regimens were purine analog-based (n=67), 2 Gy TBI-based (n=2), and others (n=1). Most CST recipients (129/137) received calcineurin inhibitors and methotrexate as graft-versus-host (GVHD) prophylaxis, while 32 RIST recipients received cyclosporin. In all, 23 CST and five RIST recipients died without disease progression within 100 days of transplant. Grade II to IV acute GVHD occurred in 56 CST and 38 RIST recipients. There was no significant difference in overall survival (OS) and progression-free survival between CST and RIST. On multivariate analysis on OS, five variables were significant: preparative regimens (CST vs RIST) (hazard ratio=1.92, 95% confidence interval, 1.25-2.97; P=0.003), performance status (2-4 vs 0-1) (2.50, 1.51-4.16; P<0.001), risk of underlying diseases (1.85, 1.21-2.83; P=0.004), acute GVHD (2.57, 1.72-3.84; P<0.001), and CML (0.38, 0.21-0.69; P=0.002). We should be careful in interpreting results of this small-sized retrospective study; however, reduced regimen-related toxicity might contribute to better survival in RIST. The low relapse rates following RIST suggest a strong antitumor activity through allogeneic immunity.

Female↗
PubMed2005

Measurements of the response functions of a large size NE213 organic liquid scintillator for neutrons up to 800 MeV.

The response functions of 25.4 cm (length) x 25.4 cm (diameter) NE213 organic liquid scintillator have been measured for neutrons in the energy range from 20 to 800 MeV at the Heavy-Ion Medical Accelerator in Chiba (HIMAC) and at the Research Center for Nuclear Physics (RCNP) of Osaka University. At HIMAC, white (continuous) energy spectrum neutrons were produced by the 400 MeV per nucleon carbon ion bombardment on a thick graphite target, whose energy spectrum has already been measured by Kurosawa et al., [Nucl. Sci. Eng. 132, 30 (1999)] and the response functions of the time-of-flight-gated monoenergetic neutrons in a wide energy range from 20 to 800 MeV were simultaneously measured. At RCNP, the quasi-monoenergetic neutrons were produced via 7Li(p,n)7Be reaction by 250 MeV proton beam bombardment on a thin 7Li target, and the TOF-gated 245 MeV peak neutrons were measured. The absolute peak neutron yield was obtained by the measurement of 478 keV gamma rays from the 7Be nuclei produced in a Li target. The measured results show that the response functions for monoenergetic neutrons < 250 MeV have a recoil proton plateau and an edge around the maximum light output, which increases with increasing incident neutron energy, on the other hand > 250 MeV, the plateau and the edge become unclear because the proton range becomes longer than the detector size and the escaping protons increase. It can be found that the efficiency of the 24.5 cm (diameter) x 25.4 cm (length) NE213 for the 250 MeV neutrons is -10 times larger than the 12.7 cm (length) x 12.7 cm (diameter) NE213, which is widely used as a neutron spectrometer.

Electrons↗
PubMed2005

[Dor operation for left ventricular aneurysm with sustained ventricular tachycardia].

A 60-year-old woman was admitted to our hospital because of syncope attack due to sustained ventricular tachycardia (VT). She was treated medically after cardiopulmonary resuscitation. Coronary arteriography revealed a 99% stenosis of right coronary artery (posterior descending artery: # 4 PD), a 90% stenosis of left descending artery (# 6) and left akinetic aneurysm was demonstrated. The patient successfully underwent Dor operation with endocardial cryoablation. The postoperative course was uneventful and the recurrence of VT was never recognized clinically.

Cardiac Surgical Procedures↗
PubMed2004

Evidence for the existence of the [2 0 2]3/2 deformed band in mirror nuclei 25Mg and 25Al.

After 50 years of its prediction, the highest-lying [2 0 2]3/2 orbit among the six Nilsson single-particle orbits originating from the sd shells in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in 25Al at excitation energies of 6-7.5 MeV in a high-resolution 25Mg(3He,t) charge-exchange reaction at 0 degrees having a strong selectivity for Gamow-Teller transitions. In the comparison with the analogous M1 transitions in 25Mg, the J(pi)=3/2(+) bandhead state and the excited 5/2(+) and 7/2(+) members were clearly assigned.

Journal Article↗
PubMed2004

The Eating Disorder Inventory-2 in Japanese clinical and non-clinical samples: psychometric properties and cross-cultural implications.

OBJECTIVE: To determine the usefulness of and cross-cultural differences in the Japanese version of the eating disorder inventory-2 (EDI-2). METHOD: A Japanese version of the EDI-2 was administered to a consecutive series (1995-2001) of 91 Japanese eating disordered inpatients and 119 matched non-clinical controls. Scores were compared with each other and with those of Canadian data previously reported. Internal consistencies were also examined. RESULTS: All subscales (except Ascetism) reached sufficient internal consistencies. The patients' mean scores were significantly higher than controls on most subscales. Restricting anorexics (AN-R) scored higher than controls on body dissatisfaction (BD) and Social Insecurity (SI) subscales. Purging bulimics (BN-P) scored higher than controls on most subscales, except for maturity fears (MF) and SI subscales. Scores of binge-eating/purging type anorexics (AN-B/P) were higher than controls on all subscales. AN-B/P and BN-P scored higher than AN-R on bulimia (B) subscale. Comparison with Canadian subjects showed that Japanese control subjects scored significantly higher on the MF, ineffectiveness (I), impulse regulation (IR), SI subscales, and lower on the perfectionism (P) subscale. DISCUSSION: The EDI-2 is useful and reliable in understanding Japanese clinical and non-clinical samples. High MF and low P subscales in our samples confirm previous findings in Chinese samples suggesting meaningful cultural differences in the emphasis placed on family bonds and individual accomplishments. In addition, high I, IR, and SI scores in Japanese non-clinical samples may reflect recent problems in Japanese culture.

Adult↗
PubMed2004

Somatosensory-evoked fields for gingiva, lip, and tongue.

To localize the oral primary somatosensory cortex, we measured somatosensory-evoked fields for the lip, gingiva, and tongue in six healthy subjects. The latency of the first peak of the posterior-oriented current in the contralateral hemisphere was 50.9 +/- 8.3 ms for the gingiva, significantly shorter than those for the lip and tongue peaks. The equivalent current dipole was localized on the central sulcus. The gingival dipole was localized significantly inferior to the lip dipole but not different from the tongue dipole. The moment of the gingival dipole was significantly smaller than that of the lip dipole but not different from that of the tongue dipole. Differences in the above parameters were negligible between the left and right, anterior and posterior, and upper and lower locations within the same organ, except that the dipole location for the anterior upper tongue was significantly inferior to that for the lower tongue.

Adult↗
PubMed2002

Spallation ultracold-neutron production in superfluid helium.

The first ultracold-neutron (UCN) production in superfluid helium placed in a spallation neutron source is carried out. A UCN density of 0.7 UCN/cm(3), which can be used in experiments, is achieved for a proton-beam power of 78 W and a He-II temperature of 1.2 K. The present new UCN source is not limited by Liouville's theorem and extraction losses, which were serious problems in the previous sources. The present source has the possibility of extremely high-density UCN production compared with previous UCN sources.

Journal Article↗
PubMed2002

Increased expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) and lymphocyte recruitment in murine gastritis induced by Helicobacter pylori.

Although T cell involvement in Helicobactor pylori-induced gastritis is known, mechanism about T cell recruitment is not understood. In this study we examined how mucosal addressin cell adhesion -molecule-1 (MAdCAM-1) is involved in lymphocyte recruitment in murine chronic gastritis induced by H. pylori. C57 BL/6 mice were infected with Sydney strain (SS1). Six months after infection, the stomach was removed. The expression of adhesion molecules, MAdCAM-1, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and the cell surface antigens CD4, CD8, CD45R/B220 or beta7-integrin were determined by immunohistochemistry. A significant increase in CD4 lymphocytes was observed in the body portion of stomach in SS1-infected mice and most of these CD4 cells express beta7-integrin, a known counter ligand for MAdCAM-1 molecule. Strong MAdCAM-1 expression was observed adjacent to these cells in the lamina propria as well as in the submucosa of SS1-infected stomach. Quantitative analysis showed that the area of MAdCAM-1 expression well correlated with the infiltration of beta7-integrin positive lymphocytes. On the other hand, expression of ICAM-1 or VCAM-1 in the lamina propria was few even in the SS1-infected stomach. Increased expression of MAdCAM-1 was well correlated to the location of lymphocytes, which express CD4 and beta7-integrin. These results suggest the possibility that MAdCAM-1 may be largely involved in the lymphocyte recruitment in the gastritis mucosa with H. pylori.

Animals↗
PubMed2001

Emotional stress activates MAP kinase in the rat heart.

Emotional stress evoked by immobilization of the rat induces c-fos mRNA or other immediate early genes. This response is mediated by activation of alpha- and beta-adrenoceptors, through mechanisms that have not yet been elucidated. Here we show that immobilization stress activates p44/p42 Mitogen-Activated Protein kinase (p44/p42 MAP kinase, Erk1/Erk2). Pretreatment with the beta1-blocker, metoprolol, did not inhibit the activation of stress-induced MAP kinase, while blockage of the alpha1-adrenoceptor by pretreatment with alpha1-blocker, prazosin or the alpha/beta-blocker, amosulalol, attenuated the activation. Application of the alpha1-agonist, phenylephrine, but not the beta-agonist, isoproterenol, to the perfused rat heart elicited MAP activation. Thus, emotional stress activates the alpha1-adrenoceptor-mediated MAP kinase pathway, whereas the pathway of the response mediated by the beta-adrenoceptor remains unknown.

Adrenergic alpha-Antagonists↗
PubMed2001

Immobilization stress-induced thymocyte apoptosis in rats.

Immobilization of rats is a well known model of emotional stress. We studied apoptosis in rat thymocytes during immobilization for 2-8 hours (h). Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells increased with time of immobilization. The positive cells increased significantly after 2 h and comprised about 33% of total cells after 8 h. The apoptotic cells aggregated as scattered foci predominantly in the cortex of the thymus and diffusely distributed with time of the stress. The DNA laddering also increased with time of immobilization, which was inhibited by a glucocorticoid receptor antagonist, RU-486. These results suggest that the emotional stress evoked by immobilization induces thymocyte apoptosis through glucocorticoid overflow.

Animals↗
PubMed2001

Ischemic preconditioning upregulates vascular endothelial growth factor mRNA expression and neovascularization via nuclear translocation of protein kinase C epsilon in the rat ischemic myocardium.

Ischemic preconditioning (IP) exerts cardioprotection through protein kinase C (PKC) activation, whereas myocardial ischemia enhances vascular endothelial growth factor (VEGF) mRNA expression. However, the IP effect or the involvement of PKC on the VEGF expression is unknown in myocardial infarction. We investigated whether IP enhances VEGF gene expression and angiogenesis through PKC activation in the in vivo myocardial infarction model. Sprague-Dawley rats were assigned into the following 3 groups: the sham group; the IP group, which underwent 3 cycles of 3 minutes of ischemia and 5 minutes of reperfusion (IP procedure); and the non-IP group. The latter 2 groups were subsequently subjected to left anterior descending coronary artery occlusion. To examine the involvement of PKC, the PKC inhibitor chelerythrine (5 mg/kg) or bisindolylmaleimide (1 mg/kg) was injected intravenously before the IP procedures. PKCepsilon was translocated to the nucleus after 10 minutes of ischemia after the IP procedure but was not translocated in the non-IP and the sham groups. VEGF mRNA expression 3 hours after infarction was significantly higher in the IP group than in the non-IP and the sham groups. Capillary density in the infarction was significantly higher, whereas the infarct size was smaller in the IP group than in the non-IP group at 3 days of infarction. Chelerythrine but not bisindolylmaleimide blocked all of the IP effects on the nuclear translocation of PKCepsilon, enhancement of VEGF mRNA expression and angiogenesis, and infarct size limitation. These results show that IP may enhance VEGF gene expression and angiogenesis through nuclear translocation of PKCepsilon in the infarcted myocardium.

Active Transport, Cell Nucleus↗