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991.
992.
Lipoprotein(a), atherosclerosis and thrombosis 总被引:1,自引:0,他引:1
G H Dahlén 《Progress in lipid research》1991,30(2-3):189-194
Lipoprotein(a) denotes cholesterol-rich particles similar to low density lipoproteins but characterized by an extra large hydrophilic glycoprotein, Apo(a), added to low density lipoproteins. Apolipoprotein(a) is bound to ApoB-100 by a disulfide bridge. Eleven different Apo(a) isoforms of varying sizes coded for by alleles at the Apo(a) gene locus on chromosome 6 have been identified, ranging in Mr between roughly 400-800 kDa. The level of lipoprotein(a) is inversely correlated with isoform size. A strong independent association between high lipoprotein(a) levels and atherosclerotic disorders is documented. Lipoprotein(a) is selectively retained in the intima and engulfed by macrophages in unmodified form. Human Apo(a) is very similar to plasminogen, which suggests that lipoprotein(a) represents a link between atherosclerosis and thrombosis. 相似文献
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994.
Olga Dolnik Larissa Kolesnikova Sonja Welsch Thomas Strecker Gordian Schudt Stephan Becker 《PLoS pathogens》2014,10(10)
Endosomal sorting complex required for transport (ESCRT) machinery supports the efficient budding of Marburg virus (MARV) and many other enveloped viruses. Interaction between components of the ESCRT machinery and viral proteins is predominantly mediated by short tetrapeptide motifs, known as late domains. MARV contains late domain motifs in the matrix protein VP40 and in the genome-encapsidating nucleoprotein (NP). The PSAP late domain motif of NP recruits the ESCRT-I protein tumor susceptibility gene 101 (Tsg101). Here, we generated a recombinant MARV encoding NP with a mutated PSAP late domain (rMARVPSAPmut). rMARVPSAPmut was attenuated by up to one log compared with recombinant wild-type MARV (rMARVwt), formed smaller plaques and exhibited delayed virus release. Nucleocapsids in rMARVPSAPmut-infected cells were more densely packed inside viral inclusions and more abundant in the cytoplasm than in rMARVwt-infected cells. A similar phenotype was detected when MARV-infected cells were depleted of Tsg101. Live-cell imaging analyses revealed that Tsg101 accumulated in inclusions of rMARVwt-infected cells and was co-transported together with nucleocapsids. In contrast, rMARVPSAPmut nucleocapsids did not display co-localization with Tsg101, had significantly shorter transport trajectories, and migration close to the plasma membrane was severely impaired, resulting in reduced recruitment into filopodia, the major budding sites of MARV. We further show that the Tsg101 interacting protein IQGAP1, an actin cytoskeleton regulator, was recruited into inclusions and to individual nucleocapsids together with Tsg101. Moreover, IQGAP1 was detected in a contrail-like structure at the rear end of migrating nucleocapsids. Down regulation of IQGAP1 impaired release of MARV. These results indicate that the PSAP motif in NP, which enables binding to Tsg101, is important for the efficient actin-dependent transport of nucleocapsids to the sites of budding. Thus, the interaction between NP and Tsg101 supports several steps of MARV assembly before virus fission. 相似文献
995.
Much recent progress has been made in understanding the structural organization and functional properties of voltage-dependent Na+ channels, in particular in the areas of activation, ion conductance, and inactivation. At the same time, however, electrophysiological studies have revealed new, more complex functional properties in the form of at least two gating modes and the existence of as yet unidentified modulatory factors. 相似文献
996.
In situ observation of localized,sub-mm scale changes of phosphorus biogeochemistry in the rhizosphere 总被引:2,自引:0,他引:2
Kreuzeder Andreas Santner Jakob Scharsching Vanessa Oburger Eva Hoefer Christoph Hann Stephan Wenzel Walter W. 《Plant and Soil》2018,424(1-2):573-589
Plant and Soil - We imaged the sub-mm distribution of labile P and pH in the rhizosphere of three plant species to localize zones and hot spots of P depletion and accumulation along individual root... 相似文献
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Emission analysis of Tb3+‐and Sm3+‐ion‐doped (Li2O/Na2O/K2O) and (Li2O + Na2O/Li2O + K2O/K2O + Na2O)‐modified borosilicate glasses 下载免费PDF全文
B. Naveen Kumar Reddy S. Sailaja K. Thyagarajan Young Dahl Jho B. Sudhakar Reddy 《Luminescence》2018,33(3):486-494
Four series of borosilicate glasses modified by alkali oxides and doped with Tb3+ and Sm3+ ions were prepared using the conventional melt quenching technique, with the chemical composition 74.5B2O3 + 10SiO2 + 5MgO + R + 0.5(Tb2O3/Sm2O3) [where R = 10(Li2O /Na2O/K2O) for series A and C, and R = 5(Li2O + Na2O/Li2O + K2O/K2O + Na2O) for series B and D]. The X‐ray diffraction (XRD) patterns of all the prepared glasses indicate their amorphous nature. The spectroscopic properties of the prepared glasses were studied by optical absorption analysis, photoluminescence excitation (PLE) and photoluminescence (PL) analysis. A green emission corresponding to the 5D4 → 7F5 (543 nm) transition of the Tb3+ ions was registered under excitation at 379 nm for series A and B glasses. The emission spectra of the Sm3+ ions with the series C and D glasses showed strong reddish‐orange emission at 600 nm (4G5/2 →6H7/2) with an excitation wavelength λexci = 404 nm (6H5/2→4F7/2). Furthermore, the change in the luminescence intensity with the addition of an alkali oxide and combinations of these alkali oxides to borosilicate glasses doped with Tb3+ and Sm3+ ions was studied to optimize the potential alkali‐oxide‐modified borosilicate glass. 相似文献
1000.
Joost Brandsma Victoria M. Goss Xian Yang Per S. Bakke Massimo Caruso Pascal Chanez Sven-Erik Dahlén Stephen J. Fowler Ildiko Horvath Norbert Krug Paolo Montuschi Marek Sanak Thomas Sandström Dominick E. Shaw Kian Fan Chung Florian Singer Louise J. Fleming Ana R. Sousa Ioannis Pandis Aruna T. Bansal Peter J. Sterk Ratko Djukanović Anthony D. Postle The U-BIOPRED Study Group 《Metabolomics : Official journal of the Metabolomic Society》2018,14(10):123