431 research outputs found
Diethyl 2-amino-5-[(E)-(furan-2-ylmethylidene)amino]thiophene-3,4-dicarboxylate
In the crystal structure of the title compound, C15H16N2O5S, the azomethine adopts the E configuration. The two heterocyclic rings adopt an antiperiplanar orientation. The mean planes of the thiophene and furan rings are twisted by 2.51 (4)°. The crystal structure exhibits intermolecular N—H⋯O hydrogen bonding. π–π stacking is also observed, the centroid-to-centroid distance being 3.770 (4) Å
Diethyl 2,5-bis[(E)-2-furylmethyleneamino]thiophene-3,4-dicarboxylate
The title compound, C20H18N2O6S, crystallizes as two independent molecules that are disposed about a pseudo-inversion center (1/2, 1/4, 1/8). The mean planes of the two terminal furyl rings are twisted with respect to the central thiophene ring by 7.33 (4) and 21.74 (5)° in one molecule, and by 6.91 (4) and 39.80 (6)° in the other
(E)-5-(2-Thienylmethyleneamino)quinolin-8-ol
Two molecules of the title compound, C14H10N2OS, are hydrogen bonded about a center of inversion. In the molecule, the two aromatic rings are twisted by 37.27 (5)° with respect to one another. The azomethine bond is in the E configuration
Diethyl 2-[(1-methyl-1H-pyrrol-2-yl)methyleneamino]-5-(2-thienylmethyleneamino)thiophene-3,4-dicarboxylate
Both imine bonds of the title compound, C21H21N3O4S2, were found to be in the E configuration. The terminal pyrrole and thiophene rings are twisted by 2.5 (3) and 2.3 (2)°, respectively, from the mean plane of the central thiophene to which they are attached. The structure is disordered by exchange of the terminal heterocyclic rings; the site occupancy factors are ca 0.8 and 0.2. The crystal packing involves some π–π stacking [3.449 (4) Å between pyrrole and terminal thiophene rings]
Diethyl 2,5-bis[(1E)-(1H-pyrrol-2-ylmethylidene)amino]thiophene-3,4-dicarboxylate
In the crystal structure of the title compound, C20H20N4O4S, the azomethine group adopt E conformations. The pyrrole units are twisted by 10.31 (4) and 18.90 (5)° with respect to the central thiophene ring. The three-dimensional network is close packed and involves N—H⋯O, N—H⋯N, C—H⋯N and C—H⋯O hydrogen bonding
Multidimensional Dynamics of the Proteome in the Neurodegenerative and Aging Mammalian Brain
Neurodegenerative diseases are characterized by the abnormal accumulation of aggregated proteins in the brain. Using in vivo pulse isotope labeling, we screened the proteome for changes in protein turnover and abundance in multiple mouse models of neurodegeneration. These data suggest that the disease state of pathologically affected tissue is characterized by a proteome-wide increase in protein turnover and repair. In contrast, in healthy wild-type mice, aging in the mammalian brain is associated with a global slowdown in protein turnover.Peer reviewe
A Networks-Science Investigation into the Epic Poems of Ossian
In 1760 James Macpherson published the first volume of a series of epic poems
which he claimed to have translated into English from ancient Scottish-Gaelic
sources. The poems, which purported to have been composed by a third-century
bard named Ossian, quickly achieved wide international acclaim. They invited
comparisons with major works of the epic tradition, including Homer's Iliad and
Odyssey, and effected a profound influence on the emergent Romantic period in
literature and the arts. However, the work also provoked one of the most famous
literary controversies of all time, colouring the reception of the poetry to
this day. The authenticity of the poems was questioned by some scholars, while
others protested that they misappropriated material from Irish mythological
sources. Recent years have seen a growing critical interest in Ossian,
initiated by revisionist and counter-revisionist scholarship and by the
two-hundred-and-fiftieth anniversary of the first collected edition of the
poems in 1765. Here we investigate Ossian from a networks-science point of
view. We compare the connectivity structures underlying the societies described
in the Ossianic narratives with those of ancient Greek and Irish sources.
Despite attempts, from the outset, to position Ossian alongside the Homeric
epics and to distance it from Irish sources, our results indicate significant
network-structural differences between Macpherson's text and those of Homer.
They also show a strong similarity between Ossianic networks and those of the
narratives known as Acallam na Sen\'orach (Colloquy of the Ancients) from the
Fenian Cycle of Irish mythology.Comment: Accepted for publication in Advances in Complex system
Extrinsic and intrinsic determinants of nerve regeneration
After central nervous system (CNS) injury axons fail to regenerate often leading to persistent neurologic deficit although injured peripheral nervous system (PNS) axons mount a robust regenerative response that may lead to functional recovery. Some of the failures of CNS regeneration arise from the many glial-based inhibitory molecules found in the injured CNS, whereas the intrinsic regenerative potential of some CNS neurons is actively curtailed during CNS maturation and limited after injury. In this review, the molecular basis for extrinsic and intrinsic modulation of axon regeneration within the nervous system is evaluated. A more complete understanding of the factors limiting axonal regeneration will provide a rational basis, which is used to develop improved treatments for nervous system injury
Defending the genome from the enemy within:mechanisms of retrotransposon suppression in the mouse germline
The viability of any species requires that the genome is kept stable as it is transmitted from generation to generation by the germ cells. One of the challenges to transgenerational genome stability is the potential mutagenic activity of transposable genetic elements, particularly retrotransposons. There are many different types of retrotransposon in mammalian genomes, and these target different points in germline development to amplify and integrate into new genomic locations. Germ cells, and their pluripotent developmental precursors, have evolved a variety of genome defence mechanisms that suppress retrotransposon activity and maintain genome stability across the generations. Here, we review recent advances in understanding how retrotransposon activity is suppressed in the mammalian germline, how genes involved in germline genome defence mechanisms are regulated, and the consequences of mutating these genome defence genes for the developing germline
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