10,126 research outputs found
Inspiral and Plunging Orbits in Kerr-Newman Spacetimes
We present the analytical solutions for the trajectories that spiral and
plunge inward the event horizon along the timelike geodesics of particles
following general non-equatorial paths within Kerr-Newman spacetimes. Our
studies encompass both bound and unbound motions. The solutions can be written
in terms of the elliptical integrals and the Jacobian elliptic functions of
manifestly real functions of the Mino time, and can respectively reduce to the
Kerr, Reissner-Nordstrm, and Schwarzschild black holes in certain
limits of the spin and charge of the black holes. The results can be compared
with some of the known ones restricted in the equatorial plane. These explicit
solutions may find applications such as the black hole accretion.Comment: 28 pages, 9 figure
Antinociceptive actions of honokiol and magnolol on glutamatergic and inflammatory pain
The antinociceptive effects of honokiol and magnolol, two major bioactive constituents of the bark of Magnolia officinalis, were investigated on animal paw licking responses and thermal hyperalgesia induced by glutamate receptor agonists including glutamate, N-methyl-D-aspartate (NMDA), and metabotropic glutamate 5 receptor (mGluR5) activator (RS)-2-chloro-5-hydroxyphenylglycine (CHPG), as well as inflammatory mediators such as substance P and prostaglandin E2 (PGE2) in mice. The actions of honokiol and magnolol on glutamate-induced c-Fos expression in the spinal cord dorsal horn were also examined. Our data showed that honokiol and magnolol blocked glutamate-, substance P- and PGE2-induced inflammatory pain with similar potency and efficacy. Consistently, honokiol and magnolol significantly decreased glutamate-induced c-Fos protein expression in superficial (I-II) laminae of the L4-L5 lumbar dorsal horn. However, honokiol was more selective than magnolol for inhibition of NMDA-induced licking behavioral and thermal hyperalgesia. In contrast, magnolol was more potent to block CHPG-mediated thermal hyperalgesia. These results demonstrate that honokiol and magnolol effectively decreased the inflammatory pain. Furthermore, their different potency on inhibition of nociception provoked by NMDA receptor and mGluR5 activation should be considered
Ser-634 and Ser-636 of Kaposi’s Sarcoma-Associated Herpesvirus RTA are Involved in Transactivation and are Potential Cdk9 Phosphorylation Sites
The replication and transcription activator (RTA) of Kaposi’s sarcoma-associated herpesvirus (KSHV), K-RTA, is a lytic switch protein that moderates the reactivation process of KSHV latency. By mass spectrometric analysis of affinity purified K-RTA, we showed that Thr-513 or Thr-514 was the primary in vivo phosphorylation site. Thr-513 and Thr-514 are proximal to the nuclear localization signal (527KKRK530) and were previously hypothesized to be target sites of Ser/Thr kinase hKFC. However, substitutions of Thr with Ala at 513 and 514 had no effect on K-RTA subcellular localization or transactivation activity. By contrast, replacement of Ser with Ala at Ser-634 and Ser-636 located in a Ser/Pro-rich region of K-RTA, designated as S634A/S636A, produced a polypeptide with ∼10 kDa shorter in molecular weight and reduced transactivation in a luciferase reporter assay relative to the wild type. In contrast to prediction, the decrease in molecular weight was not due to lack of phosphorylation because the overall Ser and Thr phosphorylation state in K-RTA and S634A/S636A were similar, excluding that Ser-634 or Ser-636 motif served as docking sites for consecutive phosphorylation. Interestingly, S634A/S636A lost ∼30% immuno-reactivity to MPM2, an antibody specific to pSer/pThr-Pro motif, indicating that 634SPSP637 motif was in vivo phosphorylated. By in vitro kinase assay, we showed that K-RTA is a substrate of CDK9, a Pro-directed Ser/Thr kinase central to transcriptional regulation. Importantly, the capability of K-RTA in associating with endogenous CDK9 was reduced in S634A/S636A, which suggested that Ser-634 and Ser-636 may be involved in CDK9 recruitment. In agreement, S634A/S636A mutant exhibited ∼25% reduction in KSHV lytic cycle reactivation relative to that by the wild type K-RTA. Taken together, our data propose that Ser-634 and Ser-636 of K-RTA are phosphorylated by host transcriptional kinase CDK9 and such a process contributes to a full transcriptional potency of K-RTA
Butylidenephthalide antagonizes cromakalim-induced systolic pressure reduction in conscious normotensive rats
Merged planning photographs of [284] southern pavilion rubble fill removed to reveal ditch fill and natural; facing west; linked as external references to excavation plan 'Thwing_4-2_excavation_plan.dwg
Bis(μ-9-anthracenemethanolato)bis[dimethylaluminium(III)]
The title complex, [Al2(CH3)4(C15H11O)2], is dimeric bridged through the O atoms of the 9-anthracenemethanolate anions. Each Al atom is tetracoordinated by two bridging O atoms from two different 9-anthracenemethanolate ligands and by two C atoms from two methyl groups, forming a distorted tetrahedral environment. The average Al—O bond distance in the Al2O2 core is 1.845 Å
Bis{1-[(E)-o-tolyldiazenyl]-2-naphtholato}copper(II)
In the title complex, [Cu(C17H13N2O)2], the CuII atom is tetracoordinated by two N atoms and two O atoms from two bidentate 1-[(E)-o-tolyldiazenyl]-2-naphtholate ligands, forming a slightly distorted square-planar environment. The two N atoms and two O atoms around the CuII atom are trans to each other, with an O—Cu—O bond angle of 177.00 (9)° and an N—Cu—N bond angle of 165.63 (10)°. The average distances between the CuII atom and the coordinated O and N atoms are 1.905 (2) and 1.995 (2)Å, respectively
Bis[μ-2-(2H-benzotriazol-2-yl)-4-methylphenolato]bis[dimethylaluminium(III)]
The title complex, [Al2(CH3)4(C13H10N3O)2], is dimeric, bridged through the O atoms of the phenolate anions. The asymmetric unit contains one half of the molecule and there is a crystallographic inversion centre in this molecule. Each Al atom is pentacoordinated by one N atom and two bridging O atoms of two N,O-bidentate benzotriazolylphenolate ligands and by two C atoms from two methyl groups, forming a distorted trigonal–bipyramidal environment
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