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Antisense oligonucleotide (ASO) is a major tool used for silencing pathogenic genes. For stroke in the hyperacute stage, however, the ability of ASO to regulate genes is limited by its poor delivery to the ischemic brain owing to sudden occlusion of the supplying artery. Here we show that, in a mouse model of permanent ischemic stroke, lipid-ligand conjugated DNA/RNA heteroduplex oligonucleotide (lipid-HDO) was unexpectedly delivered 9.6 times more efficiently to the ischemic area of the brain than to the contralateral non-ischemic brain and achieved robust gene knockdown and change of stroke phenotype, despite a 90% decrease in cerebral blood flow in the 3 h after occlusion. This delivery to neurons was mediated via receptor-mediated transcytosis by lipoprotein receptors in brain endothelial cells, the expression of which was significantly upregulated after ischemia. This study provides proof-of-concept that lipid-HDO is a promising gene-silencing technology for stroke treatment in the hyperacute stage.
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Isquemia Encefálica , Accidente Cerebrovascular , Ratones , Animales , Oligonucleótidos , ARN , Células Endoteliales/metabolismo , Ligandos , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/metabolismo , Encéfalo/metabolismo , Isquemia , ADN , LípidosRESUMEN
The relationship between the magnetorheology of bimodal magnetic elastomers with high concentrations (60 vol %) of plastic beads with diameters of 8 or 200 µm and the meso-structure of the particles was investigated. Dynamic viscoelasticity measurements revealed that the change in storage modulus of the bimodal elastomer with 200 µm beads was 2.8 × 105 Pa at a magnetic field of 370 mT. The change in the storage modulus for monomodal elastomer without beads was 4.9 × 104 Pa. The bimodal elastomer with 8 µm beads hardly responded to the magnetic field. In-situ observation for the particle morphology was performed using synchrotron X-ray CT. For the bimodal elastomer with 200 µm beads, a highly aligned structure of magnetic particles was observed in the gaps between the beads when the magnetic field was applied. On the other hand, for the bimodal elastomer with 8 µm beads, no chain structure of magnetic particles was observed. The orientation angle between the long axis of the aggregation of magnetic particles and the magnetic field direction was determined by an image analysis in three dimensions. The orientation angle varied from 56° to 11° for the bimodal elastomer with 200 µm beads and from 64° to 49° for that with 8 µm beads by applying the magnetic field. The orientation angle of the monomodal elastomer without beads changed from 63° to 21°. It was found that the addition of beads with a diameter of 200 µm linked the chains of magnetic particles, while beads with a diameter of 8 µm prevented the chain formation of the magnetic particles.
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In situ observation of the migration and structure formation of magnetic particles in polyurethane elastomers was carried out by X-ray computed tomography using synchrotron radiation. The mean diameter of the magnetic particles was 7.0 µm, and the volume fraction was Ï= 0.24 at its maximum. The exposure time was 100 ms/frame, and the pixel size was 0.458 µm/pixel. The orientation angle and the volume fraction of the maximum aggregate were analyzed using commercial software for image analysis. The orientation angle for magnetic elastomers with Ï = 0.24 was approximately 55° at 0 mT and decreased remarkably with the magnetic field. At magnetic fields above 150 mT, the orientation angle gradually decreased with the field and showed a constant value of 38° at 300 mT, suggesting that magnetic particles move and form a chain-like structure although the chains do not align perfectly in the direction of the magnetic field. On the other hand, the volume fraction of the maximum aggregate was constant at magnetic fields below 100 mT, and it significantly increased with the field, indicating that magnetic particles were connected to each other and developed into a macroscopic structure with anisotropy. Dynamic viscoelastic measurements revealed that the storage modulus of the magnetic elastomers cannot be simply scaled by the orientation angle. It was also found that the volume fraction of the maximum aggregate is a good parameter for explaining the huge increase in the storage modulus. The dynamic movement of magnetic particles when a magnetic field of 300 mT was switched on and off was also successfully observed. When the field was switched on, magnetic particles connected instantly and their aggregates were rapidly elongated in the direction of the magnetic field. When the field was switched off, some of the connections between aggregates were broken; however, most of the aggregates did not return to the original position even 5 min after being switched off.
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OBJECTIVES: A pain-free stable wrist is a prerequisite for patients with rheumatoid arthritis to improve their activity of daily life. The present study investigated whether or not radiocarpal arthrodesis yielded good results for more than 20 years. METHODS: A retrospective study was performed on 20 unstable wrists in 17 patients with rheumatoid arthritis. Radiocarpal arthrodesis combined with synovectomy and the Darrach procedure was performed. Wrist pain, grip power, the range of motion, pharmacotherapy, ESR, CRP, and serial radiographs were investigated at the baseline and 20 years after the operation. Patient-reported outcomes using the mHAQ, DASH and patient's satisfaction level were investigated at the final follow-up. RESULTS: Pain had disappeared completely in all patients at 20 years after the operation. The average grip power increased in 16 wrists (80%) and decreased in 4 wrists (20%). Wrist extension and flexion significantly decreased, and supination and pronation remained within the functional range. Radiographically, ulnar shift and palmar subluxation initially improved and remained unchanged for a long time. Fourteen patients (82.4%) with 17 wrists were satisfied with this operation. CONCLUSION: Radiocarpal arthrodesis for rheumatoid wrists provided painless stability for a long period for 20 years or more.
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Artritis Reumatoide/cirugía , Artrodesis/efectos adversos , Luxaciones Articulares/epidemiología , Dolor/epidemiología , Complicaciones Posoperatorias/epidemiología , Sinovectomía/efectos adversos , Articulación de la Muñeca/cirugía , Adulto , Anciano , Artrodesis/métodos , Femenino , Fuerza de la Mano , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Rango del Movimiento ArticularRESUMEN
BACKGROUND: Development of collateral circulation after acute ischemic stroke is triggered by shear stress that occurs in pre-existing arterioles. Recently, sphingosine-1-phosphate receptor 1 (S1P1) on endothelial cells was reported to sense shear stress and transduce its signaling pathways. METHODS: BALB/c mice (n = 118) were subjected to permanent middle cerebral artery occlusion (pMCAO) or sham operation. We investigated the effect of an S1P1-selective agonist SEW2871 on leptomeningeal collateral arteries and neurological outcome after pMCAO. RESULTS: Immunohistochemistry showed that without treatment, the expression of S1P1 on endothelial cells of leptomeningeal arteries and capillaries increased early after pMCAO, peaking at 6 hours, whereas a significant increase in the expression of S1P1 in neurons was seen from 24 hours later. After intraperitoneal administration of SEW2871 for 7 days after pMCAO, the number of leptomeningeal collateral arteries was significantly increased, cerebral blood flow improved, infarct volume was decreased, and neurological outcome improved compared with the controls. Significantly increased phosphorylation of endothelial nitric oxide synthase (eNOS) as early as 6 hours after pMCAO and higher expression of tight junction proteins at postoperative day 3 were observed with SEW2871 treatment as assessed by Western blot. Daily administration of SEW2871 also increased capillary density in peri-infarct regions and promoted monocyte/macrophage mobilization to the surface of ischemic cortex at 7 days after pMCAO. CONCLUSIONS: An S1P1-selective agonist enhanced leptomeningeal collateral circulation via eNOS phosphorylation and promoted postischemic angiogenesis with reinforced blood-brain barrier integrity in a mouse model of acute ischemic stroke, leading to smaller infarct volume and better neurological outcome.
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Circulación Cerebrovascular/efectos de los fármacos , Circulación Colateral/efectos de los fármacos , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Meninges/irrigación sanguínea , Meninges/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Oxadiazoles/farmacología , Receptores de Lisoesfingolípidos/agonistas , Tiofenos/farmacología , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Línea Celular , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Infarto de la Arteria Cerebral Media/fisiopatología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Meninges/metabolismo , Meninges/patología , Ratones Endogámicos BALB C , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Fosforilación , Receptores de Lisoesfingolípidos/metabolismo , Recuperación de la Función , Transducción de Señal/efectos de los fármacos , Receptores de Esfingosina-1-Fosfato , Proteínas de Uniones Estrechas/metabolismo , Factores de TiempoRESUMEN
A diamond phase retarder was applied to control the polarization states of a hard X-ray free-electron laser (XFEL) in the photon energy range 5-20 keV. The horizontal polarization of the XFEL beam generated from the planar undulators of the SPring-8 Angstrom Compact Free-Electron Laser (SACLA) was converted into vertical or circular polarization of either helicity by adjusting the angular offset of the diamond crystal from the exact Bragg condition. Using a 1.5 mm-thick crystal, a high degree of circular polarization, 97%, was obtained for 11.56 keV monochromatic X-rays, whereas the degree of vertical polarization was 67%, both of which agreed with the estimations including the energy bandwidth of the Si 111 beamline monochromator.
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The cerium oxidation states in single catalyst particles of Pt/Ce2Zr2O(x) (x=7 to 8) were investigated by spatially resolved nano X-ray absorption fine structure (nano-XAFS) using an X-ray nanobeam. Differences in the distribution of the Ce oxidation states between Pt/Ce2Zr2O(x) single particles of different oxygen compositions x were visualized in the obtained two-dimensional X-ray fluorescent (XRF) mapping images and the Ce L(III)-edge nano X-ray absorption near-edge structure (nano-XANES) spectra.
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There is limited information on the mechanism for platinum oxidation and dissolution in Pt/C cathode catalyst layers of polymer electrolyte fuel cells (PEFCs) under the operating conditions though these issues should be uncovered for the development of next-generation PEFCs. Pt species in Pt/C cathode catalyst layers are mapped by a XAFS (X-ray absorption fine structure) method and by a quick-XAFS(QXAFS) method. Information on the site-preferential oxidation and leaching of Pt cathode nanoparticles around the cathode boundary and the micro-crack in degraded PEFCs is provided, which is relevant to the origin and mechanism of PEFC degradation.
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A 57-year-old man whose mother had been pathologically diagnosed with Alexander disease (ALXDRD), presented with cerebellar ataxia, pyramidal signs, and mild dysarthria. Brain magnetic resonance imaging revealed typical ALXDRD alterations, such as atrophy of the medulla oblongata (MO) and cervical spinal cord, a reduced sagittal diameter of the MO, and garland-like hyperintensity signals along the lateral ventricular walls. A genetic analysis of GFAP by Sanger sequencing revealed a single heterozygous mutation of Glu to Lys at codon 332 (c.994G>A) in the GFAP gene. Our results newly confirmed that p.E332K alone is the pathogenic causative mutation for adult-onset ALXDRD.
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Enfermedad de Alexander , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Alexander/diagnóstico por imagen , Enfermedad de Alexander/genética , Codón/genética , Proteína Ácida Fibrilar de la Glía/genética , Imagen por Resonancia Magnética/métodos , Bulbo Raquídeo/diagnóstico por imagen , Bulbo Raquídeo/patología , MutaciónRESUMEN
Rheumatoid arthritis (RA) causes significant physical disability. We comprehensively investigated the relationship between RA disease activity (Disease Activity Score 28-C-reactive protein [DAS28-CRP], Simplified Disease Activity Index [SDAI], and Clinical Disease Activity Index [CDAI]), physical function (10-Meter Walk Test [10 MWT], Timed Up and Go test [TUG], Functional Reach Test [FRT], and Disabilities of the Arm, Shoulder, and Hand [DASH]), and quality of life (QOL) (Short-Form 36 [SF-36®]). We also investigated the relationship between van der Heijde's modified Total Sharp Score (mTSS), modified Health Assessment Questionnaire (mHAQ), and physical function and QOL assessments. Among 35 female patients with RA, DAS28-CRP correlated solely with DASH (r = 0.376), while SDAI and CDAI did not correlate with physical function. The mTSS-hand roentgenographic evaluation correlated with TUG (r = 0.359), FRT (r = - 0.415), and DASH (r = 0.533) among physical function assessments. The mHAQ correlated with 10 MWT (r = 0.347), TUG (r = 0.356), FRT (r = - 0.420), and DASH (r = 0.646). DAS28-CRP correlated with six of the eight subscales of SF-36®, and mTSS and mHAQ correlated with only one subscale. RA disease activity assessments may not reflect all physical functions and QOL domains of female patients with RA. Evaluating physical function and QOL in female patients with RA is essential.
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Artritis Reumatoide , Calidad de Vida , Humanos , Femenino , Equilibrio Postural , Estudios de Tiempo y Movimiento , Examen Físico , Índice de Severidad de la EnfermedadRESUMEN
CoxFe3-xO4(CFO)/Pt bilayers prepared by molecular beam epitaxy were investigated for the anomalous Hall effect and X-ray magnetic circular dichroism (XMCD). We found that the anomalous Hall effect originates from a magnetic proximity effect at the CFO/Pt interface. The XMCD signal in the Pt L-edge was obtained only for the sample deposited at 600 °C, indicating that the magnetic proximity effect is sensitive to the interface structure. Transmission electron microscopy images of the CFO/Pt interface and XMCD measurements of Co and Fe L-edges do not provide direct evidence for interfacial atomic diffusion or alloying. In summary, these results suggest that the magnetic proximity effect is robust for transport properties, such as the anomalous Hall effect, while the induced magnetic moment depends on slight differences in the interfacial structure, such as the presence or absence of interfacial oxygen ions.
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We show that bulk gold (Au) exhibits temperature-independent paramagnetism in an external magnetic field by x-ray magnetic circular dichroism spectroscopy at the Au L(2) and L(3) edges. Using the sum-rule analysis, we obtained a magnetic moment of 1.3 × 10(-4) µB/atom in an external magnetic field of 10 T and a paramagnetic susceptibility of 8.9 × 10(-6) for the 5d orbit. The induced paramagnetism in bulk Au is characterized by a large (≈ 30%) orbital contribution. This orbital component was retained even when Au atoms formed nanoparticles, playing an important role in stabilizing the spontaneous spin polarization in the Au nanoparticles.
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By using the perpendicular-exchange-biased Pt/Co/α-Cr(2)O(3) system, we provide experimental evidence that the unreversed uncompensated Cr spins exist at the Co/α-Cr(2)O(3) interface. The unreversed uncompensated Cr spin manifests itself in both the vertical shift of an element-specific magnetization curve and the relative peak intensity of soft-x-ray magnetic circular dichroism spectrum. We also demonstrate an in situ switching of the interfacial Cr spins and correspondingly a reversal of the exchange bias without interfacial atomic diffusion. Such switching shows the direct relationship between the interfacial antiferromagnetic spins and origin of the exchange bias. The demonstrated switching of exchange bias would likely offer a new design of advanced spintronics devices, using the perpendicular-exchange-biased system, with low power consumption and ultrafast operation.
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This study reports on the linear dichroism in angular-resolved photoemission from the valence band of the Heusler compounds NiTi0.9Sc0.1Sn and NiMnSb. High-resolution photoelectron spectroscopy was performed with an excitation energy of hν = 7.938 keV. The linear polarization of the photons was changed using an in-vacuum diamond phase retarder. The valence band spectra exhibit the typical structure expected from first-principles calculations of the electronic structure of these compounds. Noticeable linear dichroism is found in the valence band of both materials, and this allows for a symmetry analysis of the contributing states. The differences in the spectra are found to be caused by symmetry-dependent angular asymmetry parameters, and these occur even in polycrystalline samples without preferential crystallographic orientation.
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Brain endothelial cells (BECs) are involved in the pathogenesis of ischemic stroke. Recently, several microRNAs (miRNAs) in BECs were reported to regulate the endothelial function in ischemic brain. Therefore, modulation of miRNAs in BECs by a therapeutic oligonucleotide to inhibit miRNA (antimiR) could be a useful strategy for treating ischemic stroke. However, few attempts have been made to achieve this strategy via systemic route due to lack of efficient delivery-method toward BECs. Here, we have developed a new technology for delivering an antimiR into BECs and silencing miRNAs in BECs, using a mouse ischemic stroke model. We designed a heteroduplex oligonucleotide, comprising an antimiR against miRNA-126 (miR-126) known as the endothelial-specific miRNA and its complementary RNA, conjugated to α-tocopherol as a delivery ligand (Toc-HDO targeting miR-126). Intravenous administration of Toc-HDO targeting miR-126 remarkably suppressed miR-126 expression in ischemic brain of the model mice. In addition, we showed that Toc-HDO targeting miR-126 was delivered into BECs more efficiently than the parent antimiR in ischemic brain, and that it was delivered more effectively in ischemic brain than non-ischemic brain of this model mice. Our study highlights the potential of this technology as a new clinical therapeutic option for ischemic stroke.
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MicroARNs/genética , Oligonucleótidos/química , Oligonucleótidos/uso terapéutico , alfa-Tocoferol/química , Animales , Encéfalo/metabolismo , Línea Celular , Inmunohistoquímica , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The dynamic properties of crystalline materials are important for understanding their local environment or individual single-grain motions. A new time-resolved observation method is required for use in many fields of investigation. Here, we developed in situ diffracted X-ray blinking to monitor high-resolution diffraction patterns from single-crystal grains with a 50 ms time resolution. The diffraction spots of single grains of silver halides and silver moved in the θ and χ directions during the photolysis chemical reaction. The movements of the spots represent tilting and rotational motions. The time trajectory of the diffraction intensity reflecting those motions was analysed by using single-pixel autocorrelation function (sp-ACF). Single-pixel ACF analysis revealed significant differences in the distributions of the ACF decay constants between silver halides, suggesting that the motions of single grains are different between them. The rotational diffusion coefficients for silver halides were estimated to be accurate at the level of approximately 0.1 to 0.3 pm2/s. Furthermore, newly formed silver grains on silver halides correlated with their ACF decay constants. Our high-resolution atomic scale measurement-sp-ACF analysis of diffraction patterns of individual grains-is useful for evaluating physical properties that are broadly applicable in physics, chemistry, and materials science.
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BACKGROUND: This study aimed to evaluate the relationships between concomitant biologic disease-modifying anti-rheumatic drugs (DMARDs) and prednisolone administration and blood tacrolimus exposure or serum CYP3A4/5-related markers in rheumatoid arthritis (RA) patients without severe disease activity. METHODS: Forty-six RA patients treated with oral tacrolimus once daily for maintenance of clinical remission to moderate disease activity were enrolled. The blood concentrations of tacrolimus and its major metabolite were determined at 12â¯h after the evening dosing. Blood samples for determination of serum markers including 4ß-hydroxycholesterol (4ß-OHC), 25-hydroxyvitamin D (25-OHD) and interleukin-6 (IL-6), and CYP3A5 genotype were collected. RESULTS: Most enrolled patients had RA with clinical remission to mild disease activity. Concomitant tocilizumab or low-dose prednisolone administration did not alter the blood tacrolimus exposure. Serum 4ß-OHC level was lower in tocilizumab co-treated patients than in the biologic DMARD non-treated patients. The blood tacrolimus concentration was inversely correlated with the serum level of 25-OHD, but not 4ß-OHC and IL-6. The serum level of 4ß-OHC was positively associated with that of 25-OHD. No correlations were observed between the serum levels of CYP3A4/5 activity markers and IL-6. The patients with the homozygous CYP3A5*3 had the higher blood tacrolimus concentration, while CYP3A5*3 allele was not associated with the serum levels of 4ß-OHC and 25-OHD. CONCLUSIONS: Concomitant use of tocilizumab or low-dose prednisolone had no effect on the pharmacokinetics of tacrolimus, while tocilizumab lowered serum 4ß-OHC. Blood tacrolimus exposure was negatively associated with serum 25-OHD in RA patients with clinical remission to moderate disease activity.
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Antirreumáticos/uso terapéutico , Artritis Reumatoide/sangre , Artritis Reumatoide/tratamiento farmacológico , Citocromo P-450 CYP3A/sangre , Inmunosupresores/uso terapéutico , Prednisolona/uso terapéutico , Tacrolimus/uso terapéutico , Anciano , Antirreumáticos/administración & dosificación , Artritis Reumatoide/enzimología , Biomarcadores/sangre , Femenino , Humanos , Hidroxicolesteroles/sangre , Inmunosupresores/sangre , Límite de Detección , Masculino , Persona de Mediana Edad , Prednisolona/administración & dosificación , Tacrolimus/administración & dosificación , Vitamina D/análogos & derivados , Vitamina D/sangreRESUMEN
The aim of this study was to assess abatacept in rheumatoid arthritis (RA) patient. Patients (20 men, 89 women, aged 61.9 ± 10.4 y) who responded inadequately to conventional synthetic disease-modifying anti-rheumatic drug were treated with abatacept for 24-months. Disease activity score in 28 joints (DAS28-CRP) was evaluated. Of 109 patients, 82 (75.2%) were on methotrexate (MTX; mean dosage 9.0 ± 2.7 mg/week); 48 (44.0%) were naive to biologics and 61 (56.0%) had failed biologics. The 1- and 2-year retention rates were 77% and 53%, respectively. At 24-months, the DAS28-CRP remission rates were 54.5% in the biologic-naïve patients, and 28.2% in the biologic-failure patients (p < .01), while the structural remission rates were 83.9% and 73.1%, respectively (p = .461). Abatacept was equally effective in RA patients who were and were not on concomitant MTX. Biologic-naïve was associated with better clinical outcome. Abatacept was effective in patients who showed decreasing anti-CCP antibody titers or serum MMP-3 levels during treatment. Infection was the most frequent adverse effect of abatacept therapy. In conclusion, abatacept is more effective in biologic-naïve than in biologic-failure RA patients with or without concomitant use of MTX. Abatacept is more effective in RA patients with than without decreasing serum MMP-3 or anti-CCP antibody titers during treatment.
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Abatacept/administración & dosificación , Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antiproteína Citrulinada/sangre , Artritis Reumatoide/diagnóstico , Pueblo Asiatico , Biomarcadores/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Metaloproteinasa 3 de la Matriz , Metotrexato/administración & dosificación , Persona de Mediana Edad , Inducción de Remisión , Resultado del TratamientoRESUMEN
RATIONALE: OSAM is a rare ventriculoperitoneal (VP) shunt complication where cervical spinal cord compression by epidural venous plexus engorgement is caused by cerebrospinal fluid (CSF) overdrainage. Symmetrically indented deformity of the upper cervical spinal cord and surrounding epidural venous engorgement are characteristic radiological findings. Both of them are typically detected on magnetic resonance imaging (MRI) and enhanced computed tomography (CT). PATIENT CONCERNS: The 77-year-old man who underwent the placement of a VP shunt without an antisiphon device to treat post-subarachnoid hemorrhage (SAH) hydrocephalus presented with progressive quadriplegia 10 years postoperatively. DIAGNOSIS: MRI revealed a symmetrically indented spinal cord from the craniocervical junction (CCJ) to the C2 level and enhanced CT showed the epidural venous engorgement, which were characteristic radiological findings of overshunting-associated myelopathy (OSAM). However, MRI atypically failed to detect the engorged epidural vein and showed no compressive lesion around the spinal cord. INTERVENTION: In order to reveal how the cervical spinal cord was deformed and compressed by engorged epidural vein, CT myelography was performed. OUTCOMES: CT myelography proved that the epidural vein dynamically engorged and compressed the cervical spinal cord immediately after rotation and extension of the neck. LESSONS: CT myelography combined with neck rotation and extension revealed the dynamic change of the epidural venous engorgement, and is useful for evaluation and diagnosis of OSAM especially when epidural venous engorgement was not detectable on MRI.