193 research outputs found

    Tau phosphorylation at Alzheimer\u27s disease-related Ser356 contributes to tau stabilization when PAR-1/MARK activity is elevated.

    Get PDF
    Abnormal phosphorylation of the microtubule-associated protein tau is observed in many neurodegenerative diseases, including Alzheimer\u27s disease (AD). AD-related phosphorylation of two tau residues, Ser262 and Ser356, by PAR-1/MARK stabilizes tau in the initial phase of mismetabolism, leading to subsequent phosphorylation events, accumulation, and toxicity. However, the relative contribution of phosphorylation at each of these sites to tau stabilization has not yet been elucidated. In a Drosophila model of human tau toxicity, we found that tau was phosphorylated at Ser262, but not at Ser356, and that blocking Ser262 phosphorylation decreased total tau levels. By contrast, when PAR-1 was co-overexpressed with tau, tau was hyperphosphorylated at both Ser262 and Ser356. Under these conditions, the protein levels of tau were significantly elevated, and prevention of tau phosphorylation at both residues was necessary to completely suppress this elevation. These results suggest that tau phosphorylation at Ser262 plays the predominant role in tau stabilization when PAR-1/MARK activity is normal, whereas Ser356 phosphorylation begins to contribute to this process when PAR-1/MARK activity is abnormally elevated, as in diseased brains

    Identification and Radiofrequency Catheter Ablation of a Nonsustained Atrial Tachycardia at the Septal Mitral Annulus with the Use of a Noncontact Mapping System: A Case Report

    Get PDF
    AbstractHere we report a case of a 16-year old female with symptomatic nonsustained atrial tachycardia (NSAT) originating from the septal mitral annulus. NSAT was induced by atrial burst pacing after an intravenous isoproterenol (ISP) injection. The array mode of the noncontact mapping system (NCM) allowed us to quickly identify the tachycardia focus at the septal mitral annulus, where the contact bipolar voltage map revealed no low voltage area (<0.5 mV). The NSAT was eliminated by a radiofrequency energy application to the identified tachycardia focus during sinus rhythm, and the patient has been free from any symptoms during 10 months of follow-up

    Low energy proton-proton scattering in effective field theory

    Full text link
    Low energy proton-proton scattering is studied in pionless effective field theory. Employing the dimensional regularization and MS-bar and power divergence subtraction schemes for loop calculation, we calculate the scattering amplitude in 1S0 channel up to next-to-next-to leading order and fix low-energy constants that appear in the amplitude by effective range parameters. We study regularization scheme and scale dependence in separation of Coulomb interaction from the scattering length and effective range for the S-wave proton-proton scattering.Comment: 23 pages, 6 eps figures, revised considerably, accepted for publication in Phys. Rev.

    An Alternative Approach for Radiofrequency Catheter Ablation for Intra-atrial Reentrant Tachycardia Associated with Open-Heart Surgery

    Get PDF
    We present case reports of 2 patients with scar-related intra-atrial reentrant tachycardia (IART) associated with previous open-heart surgeries, in which standard ablation strategies failed to eliminate atrial tachycardia (AT). The strategies targeted a narrow conducting channel between the right atrial scars or between the scar and inferior vena cava. In these patients, an alternative approach to transect another narrow conducting pathway between the scar and crista terminalis (CT), which was revealed by a noncontact mapping system, successfully terminated and eliminated the IART. Both the cases were free of recurrent AT at the 24-and 25-month follow up visits, respectively. Transection of the corridor between the CT and the incision scar appears to be an effective technique for eliminating scar-related IART and can be considered as a second-line procedure for radiofrequency catheter ablation to eliminate IART

    X-ray magnetic circular dichroism and photoemission study of the diluted ferromagnetic semiconductor Zn1−x_{1-x}Crx_xTe

    Full text link
    We have performed x-ray magnetic circular dichroism (XMCD) and valence-band photoemission studies of the diluted ferromagnetic semiconductor Zn1−x_{1-x}Crx_xTe. XMCD signals due to ferromagnetism were observed at the Cr 2p absorption edge. Comparison with atomic multiplet calculations suggests that the magnetically active component of the Cr ion was divalent under the tetrahedral crystal field with tetragonal distortion along the crystalline a-, b-, and c-axes. In the valence-band spectra, spectral weight near the Fermi level was strongly suppressed, suggesting the importance of Jahn-Teller effect and the strong Coulomb interaction between the Cr 3d electrons

    SDSSp J104433.04−-012502.2 at z=5.74z=5.74 is Gravitationally Magnified by an Intervening Galaxy

    Get PDF
    During the course of our optical deep survey program on Lα\alpha emitters at z≈5.7z \approx 5.7 in the sky area surrounding the quasar SDSSp J104433.04−-012502.2 at z=5.74z=5.74, we found that a faint galaxy with mBm_B(AB) ≈25\approx 25 is located at \timeform{1".9} southwest of the quasar. Its broad-band color properties from BB to zâ€Čz^\prime suggest that the galaxy is located at a redshift of z∌1.5z \sim 1.5 -- 2.5. This is consistent with no strong emission line in our optical spectroscopy. Since the counter image of the quasar cannot be seen in our deep optical images, the magnification factor seems not to be very high. Our modest estimate is that this quasar is gravitationally magnified by a factor of 2.Comment: 11 pages, 5 figures, PASJ, in pres

    The Discovery of a Very Narrow-Line Star Forming Obat a Redshift of 5.66ject

    Full text link
    We report on the discovery of a very narrow-line star forming object beyond redshift of 5. Using the prime-focus camera, Suprime-Cam, on the 8.2 m Subaru telescope together with a narrow-passband filter centered at λc\lambda_{\rm c} = 8150 \AA with passband of Δλ\Delta\lambda = 120 \AA, we have obtained a very deep image of the field surrounding the quasar SDSSp J104433.04−-012502.2 at a redshift of 5.74. Comparing this image with optical broad-band images, we have found an object with a very strong emission line. Our follow-up optical spectroscopy has revealed that this source is at a redshift of z=5.655±0.002z=5.655\pm0.002, forming stars at a rate ∌13 h0.7−2 M⊙\sim 13 ~ h_{0.7}^{-2} ~ M_\odot yr−1^{-1}. Remarkably, the velocity dispersion of Lyα\alpha-emitting gas is only 22 km s−1^{-1}. Since a blue half of the Lyα\alpha emission could be absorbed by neutral hydrogen gas, perhaps in the system, a modest estimate of the velocity dispersion may be ≳\gtrsim 44 km s−1^{-1}. Together with a linear size of 7.7 h0.7−1h_{0.7}^{-1} kpc, we estimate a lower limit of the dynamical mass of this object to be ∌2×109M⊙\sim 2 \times 10^9 M_\odot. It is thus suggested that LAE J1044−-0123 is a star-forming dwarf galaxy (i.e., a subgalactic object or a building block) beyond redshift 5 although we cannot exclude a possibility that most Lyα\alpha emission is absorbed by the red damping wing of neutral intergalactic matter.Comment: 6 pages, 2 figures. ApJ Letters, in pres

    重症濃èș«éšœćźłć…ă«ćŻŸă™ă‚‹ć–‰é ­æ°—çźĄćˆ†é›ąăƒ»æ°—çźĄéŁŸé“ć»ćˆèĄ“ăšć–‰é ­æ°—çźĄćˆ†é›ąèĄ“ăźè‡šćșŠçš„ćŠč果

    Get PDF
    Objective: Outcomes of tracheoesophageal diversion and laryngotracheal separation were evaluated in 15 neurologically impaired children treated for intractable aspiration. Methods: A retrospective analysis of the hospital records was carried out in 15 consecutive pediatric patients who underwent either tracheoesophageal diversion or laryngotracheal separation with trumpet-shaped tracheotomy from 1999 to 2006 in Kagawa Children’s Hospital. Results: The number of hospital admissions for aspiration pneumonia after surgery was signiïŹcantly decreased in 6 patients who were cared for at home. The parent-reported number of secretion suctioning was decreased after surgery especially in patients with pre-operative tracheotomy or intubation. Four patients fed through naso-gastric tube progressed with oral diet post-operatively, whereas 3 patients who had pre-operative tracheotomy developed temporary post-operative tracheocutaneous ïŹstula that was managed by local wound care. Conclusion: It is suggested that tracheoesophageal diversion and laryngotracheal separation decrease the morbidity of pediatric patients and improve their quality of life and that of their parents. It is suggested that the risk of developing post-operative ïŹstula is higher in pediatric patients with than without pre-operative tracheotomy

    A Young Brown Dwarf Companion to DH Tauri

    Get PDF
    We present the detection of a young brown dwarf companion DH Tau B associated with the classical T Tauri star DH Tau. Near-infrared coronagraphic observations with CIAO on the Subaru Telescope have revealed DH Tau B with H = \~15 mag located at 2.3" (330 AU) away from the primary DH Tau A. Comparing its position with a Hubble Space Telescope archive image, we confirmed that DH Tau A and B share the common proper motion, suggesting that they are physically associated with each other. The near-infrared color of DH Tau B is consistent with those of young stellar objects. The near-infrared spectra of DH Tau B show deep water absorption bands, a strong K I absorption line, and a moderate Na I absorption line. We derived its effective temperature and surface gravity of Teff = 2700 -- 2800 K and log g = 4.0--4.5, respectively, by comparing the observed spectra with synthesized spectra of low-mass objects. The location of DH Tau B on the HR diagram gives its mass of 30 -- 50 M_Jupiter.Comment: 10 pages, 14 figures, 1 table, accepted for publication in Ap
    • 

    corecore