Plasma membrane cholesterol is required for efficient pseudorabies virus entry

AbstractAlphaherpesviruses comprise closely related viruses of man and animal, including herpes simplex virus, varicella-zoster virus and pseudorabies virus (PRV). Here, using methyl-beta-cyclodextrin and fluorescently tagged PRV, we directly show that depletion of cholesterol from the plasma membrane of host cells significantly reduces PRV entry. Cholesterol depletion did not reduce PRV attachment, but stalled virus particles at the plasma membrane before penetration of the cell. Cholesterol depletion results in destabilization of lipid raft microdomains in the plasma membrane, which have been shown before to be involved in efficient entry of different viruses. A significant fraction of PRV virions appears to localize juxtaposed to GM1, a lipid raft marker, during entry. Together, these data indicate that cholesterol and possibly cholesterol-rich lipid rafts may be important during PRV entry

Le projet CRUMBEL et l'apport de la recherche l'archéométrique

The CRUMBEL project aims to investigate the mobility of the former population in Belgium from the Neolithic period until the Early Middle Ages. To reach these research goals different topics will be studied. In a preliminary phase, the ancient collections of cremated bone will be documented. A selection of these funerary sites will be studied to understand the mobility using different archaeometric approaches as stable isotopes and radiocarbon dating to obtain reliable information on earlier mobility in Belgium

New dinoflagellate cysts from the Miocene of the Porcupine Basin, offshore southwest Ireland

Four new dinoflagellate cyst species from the Lower and Middle Miocene strata of the Porcupine Basin, offshore southwest Ireland. are formally described. Batiacasphaera edwardsiae sp. nov. was previously described under open nomenclature from the Miocene of the adjacent Rockall Plateau. Lejeunecysta challengerensis sp. nov. is recorded sporadically from the Burdigalian and Serravallian. Selenopemphix porcupensis sp. nov. and Trinovantedinium henrietii sp. nov. are large-sized dinoflagellate cysts with maximum dimensions of approximately 100 mu m. Selenopemphix porcupensis sp. nov. is recorded in the uppermost Burdigalian and Langhian, and Trinovantedinium henrietii sp. nov. is present in the Langhian and lowermost Batiacasphaera edwardsiae sp. nov. is possibly biostratigraphically significant for the Middle Miocene

On the cellular processing of nanomedicines for retinal gene therapy and their suitability for intravitreal injections

To restore inherited or acquired genetic defects or to silence malicious genes, nucleic acids can be introduced in somatic cells as an active compound, known as gene therapy. However, the nature of nucleic acids implicates packaging in advanced delivery systems that aid in the protection of their payload against enzymatic degradation and facilitate internalization and intracellular release into the target cells. Nanomaterials for nucleic acid delivery have been developed, however, these non-viral vectors still suffer from a relatively low efficiency in gene transfer. This lack of efficiency can be attributed to the combination of different extracellular and intracellular barriers, depending on the specific application. The future success of these nanomaterials, therefore, strongly depends on the careful scrutiny of these biological barriers, as this knowledge will support the rational design of stable, safe and effective multivalent delivery vectors that tackle all of the encountered barriers. The primary aim of this thesis was to help developing methodologies for studying in vitro the interactions of nanomedicines for retinal gene therapy with their extra- and intracellular environment, allowing both the identification of the barriers to nucleic acid transfer in a particular setup and careful evaluation of different carrier-modifications to overcome these barriers. The performed studies focused on both intravitreal stability and mobility of bioreducible polyplexes after intravitreal injection and on the interactions of these polyplexes with cultured retinal cells at the level of cell attachment, cellular internalization and intracellular trafficking. We are convinced that a strong interaction between disciplines like pharmacy, physics, chemical engineering and cell biology will facilitate the development of suitable assays that allow quantitative assessment of the several subprocesses in retinal NA delivery, both extra- as intracellularly

Contemporary global governance. Multipolarity vs new discourses on global governance

This book presents twelve studies which explore recent trends in the field of global governance. Most authors participated to the conference “Towards a new generation in global governance?”, convened by the Research Network on International Governance, Globalisation and the Transformations of the State (REGIMEN) in Ghent, Belgium, in November 2005. Later, a few other people were also invited to make a contribution. What these various papers have in common, is that they touch upon two broad trends in global governance: the deepening of multipolarity on the one hand and the emergence of new approaches, new views and new discourses on the other