66 research outputs found
Quantitative Proteomic Analysis of Stratum Corneum Dysfunction in Adult Chronic Atopic Dermatitis.
Suppressed basal mitophagy drives cellular aging phenotypes that can be reversed by a p62-targeting small molecule.
Selective degradation of damaged mitochondria by autophagy (mitophagy) is proposed to play an important role in cellular homeostasis. However, the molecular mechanisms and the requirement of mitochondrial quality control by mitophagy for cellular physiology are poorly understood. Here, we demonstrated that primary human cells maintain highly active basal mitophagy initiated by mitochondrial superoxide signaling. Mitophagy was found to be mediated by PINK1/Parkin-dependent pathway involving p62 as a selective autophagy receptor (SAR). Importantly, this pathway was suppressed upon the induction of cellular senescence and in naturally aged cells, leading to a robust shutdown of mitophagy. Inhibition of mitophagy in proliferating cells was sufficient to trigger the senescence program, while reactivation of mitophagy was necessary for the anti-senescence effects of NAD precursors or rapamycin. Furthermore, reactivation of mitophagy by a p62-targeting small molecule rescued markers of cellular aging, which establishes mitochondrial quality control as a promising target for anti-aging interventions. [Abstract copyright: Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.
Crystal Structures of AâFeClâ ·HâO (A=Rbâș, Csâș) and Field Dependent Superconducting Susceptometer Measurements
Crystal structures and low field principal crystal axis magnetic measurements are reported for the antiferromagnetic iron (III) salts A2FeCl5·H2O; A=Rb+, Cs+. The two compounds undergo a zero field paramagnetic to antiferromagnetic phase transition at 6.5 K (A=Cs+) and 10.05 K (A=Rb+). The spin flop magnetic phase is observed in high field measurements. The magnetic field-temperature phase diagrams are reported. All magnetic measurements were recorded on a superconducting susceptometer. The bicritical points are 6.25 K, 14.5 kOe (A=Cs+), 9.75 K, 17.8 KOe (A=Rb+). Crystal data for Cs2FeCl5· H2O: space group Cmcm, Z = 4, a = 7.442(3) Ă
, b = 17.307(7) Ă
, c = 8.077(7) Ă
, V = 1040 Ă
3, R = 5.2%, 561 reflections. Crystal data for Rb2FeCl5·H2O, space group Pnma, Z = 4, a = 13.825(4) Ă
, b = 9.918(3) Ă
, c = 7.100(2) Ă
, V = 4.9 Ă
3, 5.7%, 712 reflections
Magnetic Anisotropy Measurements with Orthogonal Directional SQUID Detection
A superconducting susceptometer with SQUID (superconducting quantum interference device) detectors parallel and perpendicular to the magnetic field has been used to measure single crystal magnetic susceptibility anisotropy. The method allows calculation of the parallel and perpendicular components of an axial susceptibility tensor from a single known orientation of the crystal. The magnetic anisotropy of the nitrate salts of the hexakis(pyridine N-oxide) complexes of cobalt(II) and copper(II) were analyzed with this technique. The complexes crystallize in the space group R3 with the metal atom at the center of the unit cell, which imposes a center of inversion and a threefold rotation axis at the metal atom. The NO3 - anions are positionally disordered with one main and several minor positions. The predominant position (\u3e90%) is orthogonal to the threefold axis, with the nitrogen atom on the unique axis. The [Co(C5H5NO)6]2+ cation has octahedral coordination about the metal environment and the [Cu(C5H5NO)6]2+ ion is slightly distorted from regular octahedral symmetry. The metal-ligand bond lengths are 2.090 (1) and 2.092 (2) Ă
for the cobalt and copper complexes, respectively. Crystal data are as follows: [Co(C5H5NO)6](NO3)2, space group R3, Z = 1, a = 9.489 (2) Ă
, α = 83.41 (2)°, R = 5.0%, 1050 reflections; [Cu(C5H5NO)6](NO3)2, space group RÌ3, Z = 1, a = 9.504 (3) Ă
, α = 83.41 (5)°, R = 5.4% for 640 reflections. © 1982 American Chemical Society
Low Temperature Magnetic Properties and Antiferromagnetic Interactions of the Magnetic Susceptibility Calibrant HgCo(NCS)â
High sensitivity magnetic susceptibility determinations in the range 1.3-100K, on HgCo(NCS)4, a common susceptibility calibrant, are reported. Earlier literature data reported for calibration purposes are shown to be inaccurate. Previously undetected anti- ferromagnetic interactions are shown to exist in HgCo(NCS)4, causing deviation from Curie-Weiss behavior at low temperatures. © 1979
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