162 research outputs found

    Diffraction Plane Dependence of Micro Residual Stresses in Uniaxially Extended Carbon Steels

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    In the stress measurement using X-ray or neutron diffraction, an elastic anisotropy as well as a plastic anisotropy of crystal must be carefully considered. In the X-ray and neutron diffraction stress measurement for polycrystalline materials, a particular {hkl} plane is used in measuring lattice strains. The dependence of an X-ray elastic constant on a diffraction plane is a typical example caused by an elastic anisotropy of the crystal. The yield strength and the work hardening rate of a single crystal depend on a crystallographic direction of the crystal. The difference in the yield strength and the work hardening rate relating to the crystallographic direction develops different residual stresses measured on each {hkl} diffraction after plastic deformation of a polycrystalline material. The present paper describes the result of the neutron stress measurement on uniaxially extended low and middle carbon steels. A tri-axial residual stress state developed in the extended specimens was measured on different kind of {hkl} diffraction plane. The measurement on the {110}, {200} and {211} diffraction showed that residual stresses increased with increasing the plastic elongation and the residual stresses on {110} were compressive, {200} were tensile and those on {211} were the middle of the former two planes. Received: 30 September 2010; Revised: 28 October 2010; Accepted: 1 November 201

    Characterization and Conduction Mechanism of Highly Conductive Vanadate Glass

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    This paper reviews recent studies of highly conductive barium iron vanadate glass with a composition of 20 BaO ∙ 10 Fe2O3 ∙ 70 V2O5 (in mol %). Isothermal annealing of the vanadate glass for several ten minutes at a given temperature, higher than glass transition temperature or crystallization temperature, caused an increase in σ. Substitution of CuI (3d10), ZnII (3d10) and CuII (3d9) for FeIII (3d5) was investigated to elucidate the effect of electron configuration on the conductivity (σ). A marked decrease in the activation energy of conduction (Ea) was also observed after the annealing. Values of Ea were correlated to the energy gap between the donor level and the conduction band (CB) in the n-type semiconductor model. Isothermal annealing of ZnII-substituted vanadate glass (20 BaO ∙ 5 ZnO ∙ 5 Fe2O3 ∙ 70 V2O5) at 450 °C for 30 min showed an increase in σ from 2.5 × 10–6 to 2.1 × 10–1 S cm–1, which was one order of magnitude larger than that of non-substituted vanadate glass (3.4 × 10–2 S cm–1). Under the same annealing condition, σ’s of 2.0 × 10–1 and 3.2 × 10–1 S cm–1 were observed for 20 BaO ∙ 5 Cu2O ∙ 5 Fe2O3 ∙ 70 V2O5 and 20 BaO ∙ 5 CuO ∙ 5 Fe2O3 ∙ 70 V2O5 glasses, respectively. These results demonstrate an increase in the carrier (electron) density in the CB, primarily composed of anti-bonding 4s-orbitals

    TiO2-supported Ni-Sn as an effective hydrogenation catalyst for aqueous acetic acid to ethanol

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    Various Ni and Ni-Sn catalysts supported on TiO2 were prepared and the catalytic activities were evaluated for ethanol formation from aqueous acetic acid. Although catalytic activities of the Ni/TiO2 catalysts were limited, the addition of Sn improved the activity dramatically, and the optimum Ni/Sn ratio was approximately 1:1 (w/w). SnO2, the precursor of Sn, could not be reduced into metal Sn in pure form but did reduce into Ni-Sn alloys in the presence of NiO, the precursor of Ni. Analyses with XRD and SEM-EDS revealed that the Ni-Sn alloys were homogeneously dispersed on the TiO2 surface. Furthermore, IR analysis indicated that the Ti atoms in the catalyst act as a Lewis acid, which coordinates to the oxygen atoms of acetic acid, enhancing the attack of hydrogens activated on neighboring Ni-Sn alloys. Based on these results, Ni-Sn/TiO2 is proposed as an effective hydrogenation catalyst for converting aqueous acetic acid into ethanol

    Diffraction Plane Dependence of Micro Residual Stresses in Uniaxially Extended Carbon Steels

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    In the stress measurement using X-ray or neutron diffraction, an elastic anisotropy as well as a plastic anisotropy of crystal must be carefully considered. In the X-ray and neutron diffraction stress measurement for polycrystalline materials, a particular {hkl} plane is used in measuring lattice strains. The dependence of an X-ray elastic constant on a diffraction plane is a typical example caused by an elastic anisotropy of the crystal. The yield strength and the work hardening rate of a single crystal depend on a crystallographic direction of the crystal. The difference in the yield strength and the work hardening rate relating to the crystallographic direction develops different residual stresses measured on each {hkl} diffraction after plastic deformation of a polycrystalline material. The present paper describes the result of the neutron stress measurement on uniaxially extended low and middle carbon steels. A tri-axial residual stress state developed in the extended specimens was measured on different kind of {hkl} diffraction plane. The measurement on the {110}, {200} and {211} diffraction showed that residual stresses increased with increasing the plastic elongation and the residual stresses on {110} were compressive, {200} were tensile and those on {211} were the middle of the former two planes. Received: 30 September 2010; Revised: 28 October 2010; Accepted: 1 November 201

    Case report: Novel NIPBL-BEND2 fusion gene identified in osteoblastoma-like phosphaturic mesenchymal tumor of the fibula

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    Phosphaturic mesenchymal tumor (PMT) is a rare tumor that secretes fibroblast growth factor 23 (FGF23) and causes hypophosphatemia and tumor-induced osteomalacia (TIO). Fusion genes FN1-FGFR1 and FN1-FGF1 have been detected in some PMTs, but the pathogenesis of PMTs without these fusion genes remains unclear. Here, we report a 12-year-old boy with persistent muscle weakness and gait disturbance. Roentgenographic examination revealed a radiolucent lesion with endosteal scalloping in the left fibula, while his serum level of FGF23 was markedly increased. Combined with simple X-ray findings of other body parts, we suspected that TIO was caused by PMT, and resected the tumor. After resection, the serum level of FGF23 started to decrease immediately and normalized within 3 hours after resection, with this being earlier than normalization of the serum phosphorus level. In RNA sequencing, FN1-FGFR1 and FN1-FGF1 were not detected, but a novel NIPBL-BEND2 fusion gene was identified. When we forcedly expressed this fusion gene in HEK293T cells and MG63 cells, cell proliferation was enhanced in both cell lines. Furthermore, Gene set enrichment analysis of HEK293T cells showed significant upregulation of MYC-target genes. Our results suggest that this novel NIPBL-BEND2 fusion gene promotes cell proliferation possibly via the MYC pathway and might be one of the etiologies of PMTs other than FN1-FGFR1 or FN1-FGF1

    Dual-single photon emission computed tomography and contrast-enhanced magnetic resonance imaging to evaluate dissimilar features of apical hypertrophic cardiomyopathy

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    Apical hypertrophic cardiomyopathy (HCM) is an uncommon variant of HCM characterized by hypertrophy located in the left ventricular apex that occurs at a rate of about 30% in the Japanese population. Although the prognosis of most patients with apical HCM is relatively benign, it can be poor if apical left ventricular aneurysms develop. However, the mechanism of aneurysmal formation is unclear. We describe two patients with apical HCM and dissimilar findings in 201Thallous chloride (201TlCl) and 123I-betamethyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP) dual single-photon emission computed tomography (dual-SPECT), but no myocardial fibrosis on contrast-enhanced magnetic resonance images (MRI). One had apparently normal myocardial perfusion and metabolism, whereas the other had exercise-induced myocardial ischemia and impaired myocardial metabolism. These findings indicated that even apical HCM without myocardial fibrosis is pathophysiologically heterogeneous. Apical HCM has been evaluated by either dual-SPECT or cardiac MRI, but not by both. Thus, a combination of imaging modalities is apparently essential for elucidating the pathophysiology of apical HCM. These dissimilar findings in dual-SPECT might be important in identifying patients with apical HCM who are at high risk of forming aneurysms. (Cardiol J 2010; 17, 3: 306-311

    <症例>胃癌手術 (脾摘術合併胃全摘術) 後の門脈血栓症の1例

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    A 48-year-old woman underwent total gastrectomy, splenectomy, and distal pancreatectomy with en bloc regional lymph node dissection for gastric carcinoma. Dull pain in the right upper quadrant and the back developed postoperatively. Contrast-enhanced computed tomography and ultrasonography disclosed portal vein thrombosis (PVT). Heparin and urokinase were given in conjunction with antbiotics. This treatment resulted in clinical improvement, but failed to achieve complete thrombolysis. Cavernous transformation of the portal system was confirmed. Although PVT after splenectomy has been reported mainly in patients with hematological disorders, our case suggests that splenectomy for en bloc node dissection in gastric carcinoma is a possible cause of PVT.門脈血栓症は肝硬変や肝癌の患者で時に認められる病態であるが, 術後の門脈血栓症は稀であり, そのほとんどが脾腫に対する脾摘術後に発生している. 我々は胃癌根治術に伴う脾摘術後に門脈血栓をきたした症例を経験したので報告する. 症例は48才の女性で, 胃体上部後壁を中心とする5型胃癌に対し, 胃全摘術, 脾摘術, 膵尾側切除術を行なった. 病変は組織学的には低分化腺癌, 深達度ss, No, Po, Ho の stage I b で, 摘出した脾重量は 150g であった. なお, 術前の出血凝固系検査には異常を認めなかった. 術後18日目より右上腹部から背部の鈍痛が出現し, 白血球数, CRP, 血清アルカリフォスファターゼ値も上昇してきた. 術後19日目の造影CTで, 門脈, 上腸間膜静脈がほとんど造影されず, 門脈から上腸間膜静脈におよぶ血栓形成が考えられた. 抗生剤の投与とともにただちにへパリンの持続静注とウロキナーゼ投与を併用したところ, 臨床症状や検査所見は軽快した. ただし, 血栓は完全に消失せず, その後の腹部血管造影では側副血行路としての肝十二指腸間膜内の静脈拡張, いわゆるcavernous transformation が認められた. へパリン, ウロキナーゼの投与からワーファリン内服に切り替え, 患者は術後66日目に退院した. 現在, 術後2年経過したが, 食道静脈瘤の出現や消化管出血などの門脈血栓, 門脈圧充亢進に起因すると思われる症状は認めていない. 我々の症例は, 進行胃癌根治術の際にしばしは合わせ行われる脾摘術後にも門脈血栓症の出現する可能性があることを示唆しており, そのような手術を受けた患者が術後原因不明の腹部症状や白血球増加を来たした時には門脈血栓症も疑い精査を進める必要があると考えられる

    Cellular HIV-1 DNA levels in patients receiving antiretroviral therapy strongly correlate with therapy initiation timing but not with therapy duration

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    <p>Abstract</p> <p>Background</p> <p>Viral reservoir size refers to cellular human immunodeficiency virus-1 (HIV-1) DNA levels in CD4<sup>+ </sup>T lymphocytes of peripheral blood obtained from patients with plasma HIV-1-RNA levels (viral load, VL) maintained below the detection limit by antiretroviral therapy (ART). We measured HIV-1 DNA levels in CD4<sup>+ </sup>lymphocytes in such patients to investigate their clinical significance.</p> <p>Methods</p> <p>CD4<sup>+ </sup>T lymphocytes were isolated from the peripheral blood of 61 patients with a VL maintained at less than 50 copies/ml for at least 4 months by ART and total DNA was purified. HIV-1 DNA was quantified by nested PCR to calculate the copy number per 1 million CD4<sup>+ </sup>lymphocytes (relative amount) and the copy number in 1 ml of blood (absolute amount). For statistical analysis, the Spearman rank or Wilcoxon signed-rank test was used, with a significance level of 5%.</p> <p>Results</p> <p>CD4 cell counts at the time of sampling negatively correlated with the relative amount of HIV-1 DNA (median = 33 copies/million CD4<sup>+ </sup>lymphocytes; interquartile range [IQR] = 7-123 copies/million CD4<sup>+ </sup>lymphocytes), but were not correlated with the absolute amounts (median = 17 copies/ml; IQR = 5-67 copies/ml). Both absolute and relative amounts of HIV-1 DNA were significantly lower in six patients in whom ART was initiated before positive seroconversion than in 55 patients in whom ART was initiated in the chronic phase, as shown by Western blotting. CD4 cell counts before ART introduction were also negatively correlated with both the relative and absolute amounts of HIV-1 DNA. Only the relative amounts of HIV-1 DNA negatively correlated with the duration of VL maintenance below the detection limit, while the absolute amounts were not significantly correlated with this period.</p> <p>Conclusions</p> <p>The amounts of cellular HIV-1 DNA in patients with VLs maintained below the detection limit by the introduction of ART correlated with the timing of ART initiation but not with the duration of ART. In addition, CD4<sup>+ </sup>T lymphocytes, which were newly generated by ART, diluted latently infected cells, indicating that measurements of the relative amounts of cellular HIV-1 DNA might be underestimated.</p

    高齢の非代償性心不全患者において、非心血管疾患、特に感染症は重要な死因である

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    BACKGROUND:Despite marked improvements in treatment strategies for heart failure (HF), the mortality rate of elderly patients with HF is still high. Detailed causes of death have not been fully understood.METHODS AND RESULTS:We studied 459 consecutive patients with acute decompensated HF (ADHF) emergently admitted to our hospital from 2007 to 2011. Patients were divided into 2 groups: <75 years old (younger group; n = 225) and ≥75 years old (elderly group; n = 234). All-cause death, cardiovascular death, and noncardiovascular death were assessed as adverse outcomes. Compared with the younger group, the elderly group was characterized by a higher proportion of women and hypertensive patients and higher left ventricular ejection fraction. During a mean follow-up of 20.7 months, a total of 174 patients (37.9%) died. All-cause death was significantly higher in the elderly group than in the younger group (46.6% vs 28.9%; P < .0001), and this difference was caused by an increase in noncardiovascular deaths (20.9% vs 9.3%; P < .001), especially deaths due to infection (10.7% vs 4.0%; P < .01). Cardiovascular deaths did not differ between the 2 groups.CONCLUSIONS:Noncardiovascular deaths, most of which were caused by infection, were frequent among elderly patients with ADHF.博士(医学)・甲第629号・平成27年3月16日Copyright © 2014 Elsevier Inc. All rights reserved
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