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1.
J Synchrotron Radiat ; 30(Pt 2): 301-307, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36891843

RESUMO

An insertion device capable of switching the operation mode between helical and figure-8 undulators, and thus referred to as a helical-8 undulator, has been developed. It has the advantage that the on-axis heat load can be kept low regardless of the polarization state, even when a high K value is required to lower the fundamental photon energy. This is in contrast to conventional undulators in which the on-axis heat load tends to be significantly high to generate linearly polarized radiation with a high K value, and optical elements can be seriously damaged. The principle of operation, specification and light source performance of the developed helical-8 undulator are presented together with further options to enhance its capability.

2.
J Synchrotron Radiat ; 29(Pt 3): 670-676, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35511000

RESUMO

This work has successfully demonstrated a system for monitoring pink-beam X-rays exiting from a beamline front-end, which has a specific spatial distribution based on each energy component. In this study, the X-rays scattered from a single-crystal chemical-vapor-deposited diamond film were converted into a cross-sectional image using pinhole optics, followed by digitization with a direct detection complementary metal-oxide-semiconductor 2D detector. By using single crystals instead of poly-crystals, good quality images were obtained with no diffraction bright spots. As a result of applying photon energy discrimination using the droplet analysis to the image information, the spatial distribution of each energy component of the undulator radiation was successfully visualized. The result was found to be in good agreement with the theoretically calculated result obtained using the synchrotron radiation calculation code SPECTRA. The new synchrotron radiation beam monitor proposed in this paper can serve as a powerful beam diagnostic tool for diffraction-limited rings that require strict light source stability.

3.
J Synchrotron Radiat ; 21(Pt 2): 352-65, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24562556

RESUMO

A new soft X-ray beamline, BL07LSU, has been constructed at SPring-8 to perform advanced soft X-ray spectroscopy for materials science. The beamline is designed to achieve high energy resolution (E/ΔE> 10000) and high photon flux [>10(12) photons s(-1) (0.01% bandwidth)(-1)] in the photon energy range 250-2000 eV with controllable polarization. To realise this state-of-the-art performance, a novel segmented cross undulator was developed and adopted as a light source. The details of the undulator light source and beamline monochromator design are described. The achieved performance of the beamline, such as the photon flux, energy resolution and the state of polarization, is reported.

4.
Biosci Biotechnol Biochem ; 78(2): 212-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25036673

RESUMO

MUC5AC mucin overproduction is a key feature of asthma as contributes to airway obstruction. The production of MUC5AC is regulated in part by signals from extracellular matrix via integrin pathways, but it remains largely unclear. We investigated the role of Akt, a typical signal transducer in the integrin pathway, in the regulation of MUC5AC production. When NCI-H292 human airway epithelial cells were cultured on laminin or Matrigel, we found that the activity of Akt was suppressed, as compared to control cells with upregulated MUC5AC production. In contrast, Akt was activated in cells cultured on type IV collagen with downregulated MUC5AC production. The Akt inhibitor induced upregulation of MUC5AC. In contrast, overexpression of active Akt induced downregulation of MUC5AC production. These results suggest that a signal from laminin or Matrigel induces upregulation of MUC5AC by suppressing Akt activity, whereas a signal from type IV collagen induces downregulation of MUC5AC, mediated by Akt activation.


Assuntos
Regulação para Baixo , Células Epiteliais/citologia , Matriz Extracelular/metabolismo , Mucina-5AC/biossíntese , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sistema Respiratório/citologia , Linhagem Celular Tumoral , Colágeno/farmacologia , Colágeno Tipo IV/farmacologia , Regulação para Baixo/efeitos dos fármacos , Combinação de Medicamentos , Células Epiteliais/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Humanos , Laminina/farmacologia , Muco/metabolismo , NF-kappa B/metabolismo , Proteoglicanas/farmacologia
5.
Intern Med ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38839332

RESUMO

A 79-year-old woman developed herpes zoster ophthalmicus (HZO) with a vesicular rash on the nasal root, which developed soon after intravenous acyclovir therapy. Although varicella zoster virus DNA was undetectable in the cerebrospinal fluid, she presented with ophthalmoplegia without optic nerve dysfunction 32 days after the onset of HZO. We diagnosed the patient with superior orbital fissure syndrome and administered intravenous immunoglobulin and systemic corticosteroids. Ophthalmoplegia did not immediately respond to these therapies but resolved 4 months later. We should be aware that ophthalmoplegia can occur, even after HZO and meningitis are completely treated.

6.
Intern Med ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38897960

RESUMO

An 86-year-old woman was admitted to our hospital with cryptogenic progressive dyspnea and dysphagia following a tracheostomy procedure 4 months prior to presentation. She exhibited fluctuating diplopia, bilateral vocal fold paralysis, normal nerve test results, negative findings for serum anti-acetylcholine receptor and anti-muscle-specific kinase antibodies, and positive findings for anti-LDL-receptor related protein 4 (LRP4). A videofluoroscopic swallowing study (VFSS) with edrophonium revealed an improvement in bulbar paralysis. Consequently, the patient was diagnosed with double-seronegative myasthenia gravis (DSN-MG) and began immunomodulatory therapy. This case emphasizes the diagnostic challenges of bulbar-type DSN-MG and underscores the value of a VFSS with edrophonium for diagnosing this condition.

7.
J Synchrotron Radiat ; 20(Pt 1): 67-73, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23254657

RESUMO

Following a successful study on the prediction of fatigue life of high-heat-load components made of Glidcop, the thermal limitation of oxygen-free copper (OFC), which is used more commonly than Glidcop, has been studied. In addition to its general mechanical properties, the low-cycle-fatigue (LCF) and creep properties of OFC were investigated in detail and compared with those of Glidcop. The breaking mode of OFC, which was observed to be completely different from that of Glidcop in a fatigue fracture experiment, clarified the importance of considering the creep-fatigue interaction. An additional LCF test with compressive strain holding was conducted so that the creep-fatigue life diagram for out-of-phase thermal fatigue could be obtained on the basis of the strain-range partitioning method. The life predicted from elasto-plastic creep analysis agreed well with that determined from the void ratio estimated in the fatigue fracture experiment.

8.
Intern Med ; 62(23): 3525-3530, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38044116

RESUMO

A 70-year-old woman with advanced endometrial cancer developed right ptosis and muscle weakness in the right quadriceps after pembrolizumab administration. Serum creatine kinase (CK) levels were elevated, and anti-striated muscle antibodies were positive. On magnetic resonance imaging, the right vastus lateral muscle showed an abnormal signal. She was diagnosed with pembrolizumab-induced myopathy. We initiated plasma exchange (PE), and the ptosis immediately resolved. We then introduced oral corticosteroids, which improved her muscle weakness. We were able to rapidly diagnose her with ocular symptoms and serum CK level elevation. The early initiation of PE might prevent the exacerbation of pembrolizumab-induced myopathy.


Assuntos
Blefaroptose , Doenças Musculares , Miastenia Gravis , Feminino , Humanos , Idoso , Troca Plasmática , Miastenia Gravis/induzido quimicamente , Miastenia Gravis/tratamento farmacológico , Doenças Musculares/induzido quimicamente , Doenças Musculares/terapia , Debilidade Muscular , Músculos
9.
J Synchrotron Radiat ; 19(Pt 3): 388-93, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22514174

RESUMO

The soft X-ray beamline BL23SU at SPring-8 has undergone an upgrade with a twin-helical undulator of in-vacuum type to enhance the experimental capabilities of the endstations. The new light source with a fast helicity-switching operation allows not only the data throughput but also the sensitivity in X-ray magnetic circular dichroism (XMCD) to be improved. The operational performance and potential are described by presenting XMCD results of paramagnetic ß-US(2) measured with a 10 T superconducting magnet.

10.
J Neurol Sci ; 421: 117284, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360732

RESUMO

Chronic progressive neuro-Behçet's disease (CPNBD) is characterized by slowly progressive cognitive decline, cerebellar ataxia, and brainstem atrophy without acute encephalomeningitis. To evaluate the progression of CPNBD during treatment, we conducted a retrospective, longitudinal comparative analysis of the clinical features and brain magnetic resonance imaging (MRI) in patients with CPNBD. We classified participants into three groups: NBD with acute encephalomeningitis alone (Group A, 8 patients with acute neuro-Behçet's disease [ANBD]), primary progressive CPNBD (Group B, 3 patients), and a combination of acute encephalomeningitis, and chronic progression (Group C, 2 patients). Routine laboratory tests and monthly rate of enlargement of the width of the third ventricle (ΔWTVm) and relative value of ΔWTVm to the transverse cerebral diameter (ΔWTVIm) were statistically evaluated. Although higher cell count values and interleukin-6 concentration in the cerebrospinal fluid were observed in ANBD, both ΔWTVm (p = 0.008) and ΔWTVIm (p = 0.008) were significantly larger in CPNBD phase than in the ANBD phase. Effective treatment for CPNBD seemed to reduce ΔWTVm and ΔWTVIm in some patients. Sequential evaluation of WTV in patients with CPNBD is a highly sensitive candidate biomarker of early diagnosis and treatment efficacy.


Assuntos
Síndrome de Behçet , Terceiro Ventrículo , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/diagnóstico por imagem , Biomarcadores , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
11.
Rev Sci Instrum ; 91(3): 033103, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32259919

RESUMO

With low-emittance synchrotron radiation rings, introducing accurate x-ray beams to a sample is difficult, and ensuring that the direction of the undulator beam is stable is essential. However, measuring the centroid of the undulator photon beam at the beamline front-end (FE) is difficult because the soft x-ray radiation is contaminated by the bending magnets upstream and downstream of the undulator. The x-ray beam position monitors (XBPMs), based on the interaction with the halo of undulator radiation, cannot estimate the centroid of the beam, and they cannot eliminate the effects of the bending magnets. To solve this problem, we have developed an energy-resolved beam-monitoring system for undulator radiation with the scattering from a diamond thin film deposited by chemical vapor deposition (CVD) in this study. An undulator x-ray beam is irradiated onto this film, and its elastic and Compton scattering are observed through a 50 µm-diameter pinhole. A beam spot is detected through a pinhole camera system using a direct-detection-type charge-coupled device camera with energy resolution. The peak of the first-order harmonic of the undulator radiation is selectively visualized to measure the centroid of the undulator radiation, as well as the spectrum. The proposed system using a CVD diamond film can provide accurate position information for a photon beam exiting the FE.

12.
Rev Sci Instrum ; 87(8): 083111, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27587104

RESUMO

A new beam profile monitoring system for the small X-ray beam exiting from the SPring-8 front-end was developed and tested at BL13XU. This system is intended as a screen monitor and also as a position monitor even at beam currents of 100 mA by using photoluminescence of a chemical vapor deposition-grown diamond film. To cope with the challenge that the spatial distribution of the photoluminescence in the vertical direction is too flat to detect the beam centroid within a limited narrow aperture, a filter was installed that absorbs the fundamental harmonic concentrated in the beam center, which resulted in "de-flattening" of the vertical distribution. For the measurement, the filter crossed the photon beam vertically at high speed to withstand the intense heat flux of the undulator pink-beam. A transient thermal analysis, which can simulate the movement of the irradiation position with time, was conducted to determine the appropriate configuration and the required moving speed of the filter to avoid accidental melting. In a demonstration experiment, the vertically separated beam profile could be successfully observed for a 0.8 × 0.8 mm(2) beam shaped by an XY slit and with a fundamental energy of 18.48 keV. The vertical beam centroid could be detected with a resolution of less than 0.1 mm.

13.
J Synchrotron Radiat ; 15(Pt 2): 144-50, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18296780

RESUMO

A procedure to predict the fatigue fracture life of high-heat-load components made of GlidCop has been successfully established. This method is based upon the Manson-Coffin equation with a cumulative linear damage law. This prediction was achieved by consolidating the results of experiments and analyses, and considered the effects of environment and creep. A low-cycle-fatigue test for GlidCop was conducted so that environment-dependent Delta(t)-N(f) diagrams for any temperature could be prepared. A special test piece was designed to concentrate the strain in a central area locally, resulting in the low-cycle-fatigue fracture. The experiments were carried out by repeatedly irradiating a test piece with an electron beam. The results of the experiment confirmed that the observed fatigue life was within a factor of two when compared with the predicted fatigue life, yet located on the safer side.

14.
J Synchrotron Radiat ; 15(Pt 1): 1-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18097071

RESUMO

The thermal contact conductance (TCC) of a real front-end component at SPring-8 has been quantitatively estimated by comparing the results of experiments with those of finite-element analyses. In this paper one of the methods of predicting the TCC of a real instrument is presented. A metal filter assembly, which is an indirect-cooling instrument, was selected for the estimation of the TCC. The temperature of the metal filter assembly for the maximum heat load of synchrotron radiation was calculated from the TCC that is expected under normal conditions. This study contributes towards the ongoing research program being conducted to investigate the real thermal limitation of all front-end high-heat-load components.

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