Search results for "Filament"
showing 5 items of 405 documents
Higher-order Kerr terms allow ionization-free filamentation in gases
2010
Talk given by J. Kasparian; International audience; Higher-order nonlinear indices, rather than plasma, provide the main defocusing contribution to filamentation in gases at 800 nm. Developing generalized Miller formulae, we discuss the generality of this as a function of the laser wavelength
Evolutionary Dynamics of Pathoadaptation Revealed by Three Independent Acquisitions of the VirB/D4 Type IV Secretion System in Bartonella
2017
The α-proteobacterial genus Bartonella comprises a group of ubiquitous mammalian pathogens that are studied as a model for the evolution of bacterial pathogenesis. Vast abundance of two particular phylogenetic lineages of Bartonella had been linked to enhanced host adaptability enabled by lineage-specific acquisition of a VirB/D4 type IV secretion system (T4SS) and parallel evolution of complex effector repertoires. However, the limited availability of genome sequences from one of those lineages as well as other, remote branches of Bartonella has so far hampered comprehensive understanding of how the VirB/D4 T4SS and its effectors called Beps have shaped Bartonella evolution. Here, we repor…
Chronic ethanol exposure alters the levels, assembly, and cellular organization of the actin cytoskeleton and microtubules in hippocampal neurons in …
2010
The organization and dynamics of microtubules (MTs) and the actin cytoskeleton are critical for the correct development and functions of neurons, including intracellular traffic and signaling. In vitro ethanol exposure impairs endocytosis, exocytosis, and nucleocytoplasmic traffic in astrocytes and alters endocytosis in cultured neurons. In astrocytes, these effects relate to changes in the organization and/or function of MTs and the actin cytoskeleton. To evaluate this possibility in hippocampal cultured neurons, we analyzed if chronic ethanol exposure affects the levels, assembly, and cellular organization of both cytoskeleton elements and the possible underlying mechanisms of these effec…
Microtubules and microfilaments in HSV-Infected rabbit-kidney cells.
1981
In rabbit kidney cells infected with strains of Herpes simplex virus producing either cell-rounding or polycaryocytosis. Vinblastine induced paracrystals. This could be shown by phase-contrast- and electron-microscopy. Infections were done under one-step-growth conditions or at low MOI. 90 per cent noninfected cells contained stress fibers as detected by Servablue R250-staining. Shortly after recruitment into polycaryocytes, stress fibres of normal length appearing in criss-cross arrangement can be seen in the periphery of these cells. Later they polymerize to very long fibers and finally they are partially destroyed. The time of destruction depends on the MOI employed. By using Actinomycin…
Conservation of the positions of metazoan introns from sponges to humans
2002
Abstract Sponges (phylum Porifera) are the phylogenetic oldest Metazoa still extant. They can be considered as reference animals (Urmetazoa) for the understanding of the evolutionary processes resulting in the creation of Metazoa in general and also for the metazoan gene organization in particular. In the marine sponge Suberites domuncula , genes encoding p38 and JNK kinases contain nine and twelve introns, respectively. Eight introns in both genes share the same positions and the identical phases. One p38 intron slipped for six bases and the JNK gene has three more introns. However, the sequences of the introns are not conserved and the introns in JNK gene are generally much longer. Intron…