Authors:Markus Krohn, Thomas Wanek, Marie-Claude Menet, Andreas Noack, Xavier Declèves, Oliver Langer, Wolfgang Löscher, and Jens Pahnke
successful humanization of the Abcg2 gene in mice by exchanging the 107 kbp mouse gene for the 141 kbp human gene. The approach may suffer from the unpredictability of disrupting long-range transcriptional elements or possible incompatibilities between
Authors:Boussenane Nadia, Kebsa Wided, Boutabet Kheira, Rouibah Hassiba, Benguedouar Lamia, S. Rhouati, M. Alyane, A. Zellagui, and M. Lahouel
This paper reports an investigation of the ability of propolis extract (a resinous substance collected by honeybees from various plant sources) to restore the collapse of mitochondrial membrane potential induced by ferulenol, a sesquiterpene prenylated coumarin derivative isolated from the plant
. We show that ferulenol was able to induce the permeability transition pore (PTP) opening. This effect is caused by the interaction of the compound with the mitochondrial respiratory chain, more particularly by the fall of membrane potential and the inhibition of complex II. We have previously demonstrated that this inhibition results from a limitation of electron transfers involved in the respiratory chain and initiated by the reduction of ubiquinone. We hypothesized that the protective effect of propolis could be due to a direct action on mitochondrial functions. So we have investigated
the mitochondrial effects of Algerian propolis using rat liver mitochondria, by analysing their effects on membrane potential, mitochondrial respiration and mitochondrial swelling. We show that propolis extract was able to restore the fall of mitochondrial membrane potential. Taken together these data reveal that propolis extract may be an interesting inhibitor of PTP and provide an additional mechanism by which the natural product propolis extract may restore the mitochondrial membrane potential and to prevent apoptotic process.
Authors:C. Battisti, E. Ukmar, L. Luiselli, and M. Bologna
Breeding bird communities were studied by line-transect in burnt pinewood and unburnt pinewoods, during three years subsequently to a fire event, in a coastal woodland of Mediterranean central Italy. We analyzed data following a diversity/dominance approach that ranks the species in order of their abundance, to obtain rank/abundance diagrams (‘Whittaker plots’). Although it is generally accepted that fire may induce structural changes in forest communities of breeding birds, we observed more evident effects when considering the assemblage of forest-specialist species. When considering the whole community of birds, ordinate intercepts of the regression between rank and relative abundance of species were not significantly different between unburnt and burnt plots in any of the three years of study. However, when considering only the forest-related species, there was a significant difference between unburnt and burnt plots in all the years of study. Evenness showed lower values that were explicited by the diversity/dominance diagrams (lower collocation of the curves of burnt pinewoods if compared to unburnt ones). Overall, the patterns observed in this study suggest that the effects of fire disturbance were more evident at the ecological level than at the taxonomic-level assemblages. The gradual decline of the more sensitive species due to fires and the proportional increase of edge/generalist species may induce a species turnover in burnt woods with cascade and relaxation effects which could be evidenced by diversity/dominance diagrams. Consequently, it is useful to separate the effects of fires at community-level and at assemblage-level when studying bird communities in areas subjected to fires.
Authors:Y. Jing, Y. Hao, H. Qu, Y. Shan, D. Li, and R. Du
Helander, I. M., Nurmiaho-Lassila, E. L., Ahvenainen, R., Rhoades, J., Roller, S. (2001) Chitosan disrupts the barrier properties of the outer membrane of Gram-negative bacteria.
Int. J. Food Microbiol. 71
Authors:Manja Boehm, Daniel Simson, Ulrike Escher, Anna-Maria Schmidt, Stefan Bereswill, Nicole Tegtmeyer, Steffen Backert, and Markus M. Heimesaat
junctional proteins leads to disruption of the epithelial barrier (4), paving the way for bacteria to transmigrate across the cell monolayer by a paracellular route (5) and to enter deeper tissues (6). In addition, HtrA is also involved in bacterial adhesion
Authors:Peter Ilgen, Frank Maier, and Wilhelm Schäfer
, C., von Wettstein, D., Schäfer, W., Kogel, K.H., Felk, A., Maier F.J. 2005. Infection patterns in barley and wheat spikes inoculated with wild-type and trichodiene synthase disrupted