Provider: - Institution: - Data provided by Europeana Collections- Rekonstrukcija plovbe rimske tovorne ladje, odkrite pri Lipah leta 1890. Ladjo so premikali z odrivanjem, vzdolž desnega boka je ...bil prostor, kjer se je gibala posadka. Uporabljali so dolge lesene drogove.Risba je bila objavljena v: Ljubljanica. Kulturna dediščina reke (ur. P. Turk in dr.), Ljubljana 2009, str. 108, sl. 122.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Following the finding that ammodytoxin (Atx), a neurotoxic secreted phospholipase A2 (sPLA2) in snake venom, binds specifically to protein disulfide isomerase (PDI) in vitro we show that these ...proteins also interact in living rat PC12 cells that are able to internalize this group IIA (GIIA) sPLA2. Atx and PDI co-localize in both differentiated and non-differentiated PC12 cells, as shown by fluorescence microscopy. Based on a model of the complex between Atx and yeast PDI (yPDI), a three-dimensional model of the complex between Atx and human PDI (hPDI) was constructed. The Atx binding site on hPDI is situated between domains b and b'. Atx interacts hPDI with an extensive area on its interfacial binding surface. The mammalian GIB, GIIA, GV and GX sPLA2s have the same fold as Atx. The first three sPLA2s have been detected intracellularly but not the last one. The models of their complexes with hPDI were constructed by replacement of Atx with the respective mammalian sPLA2 in the Atx-hPDI complex and molecular docking of the structures. According to the generated models, mammalian GIB, GIIA and GV sPLA2s form complexes with hPDI very similar to that with Atx. The contact area between GX sPLA2 and hPDI is however different from that of the other sPLA2s. Heterologous competition of Atx binding to hPDI with GV and GX sPLA2s confirmed the model-based expectation that GV sPLA2 was a more effective inhibitor than GX sPLA2, thus validating our model. The results suggest a role of hPDI in the (patho)physiology of some snake venom and mammalian sPLA2s by assisting the retrograde transport of these molecules from the cell surface. The sPLA2-hPDI model constitutes a valuable tool to facilitate further insights into this process and into the (patho)physiology of sPLA2s in relation to their action intracellularly.
Understanding the molecular basis of ligand-DNA-binding events, and its application to the rational design of novel drugs, requires knowledge of the structural features and forces that drive the ...corresponding recognition processes. Existing structural evidence on DNA complexation with classical minor groove-directed ligands and the corresponding studies of binding energetics have suggested that this type of binding can be described as a rigid-body association. In contrast, we show here that the binding-coupled conformational changes may be crucial for the interpretation of DNA (hairpin) association with a classical minor groove binder (netropsin). We found that, although the hairpin form is the only accessible state of ligand-free DNA, its association with the ligand may lead to its transition into a duplex conformation. It appears that formation of the fully ligated duplex from the ligand-free hairpin, occurring via two pathways, is enthalpically driven and accompanied by a significant contribution of the hydrophobic effect. Our thermodynamic and structure-based analysis, together with corresponding theoretical studies, shows that none of the predicted binding steps can be considered as a rigid-body association. In this light we anticipate our thermodynamic approach to be the basis of more sophisticated nucleic acid recognition mechanisms, which take into account the dynamic nature of both the nucleic acid and the ligand molecule.
We have investigated new and retrieved cementless hip endoprostheses that prematurely failed due to (i) aseptic loosening, (ii) infection and (iii) latent infection. The aim was to better understand ...the physico-chemical phenomena on the surfaces and sub-surfaces of the Ti6Al7Nb alloy implant. The results of our studies should enable us to distinguish the causes of premature failure, optimize the surface modification, achieve optimal osseointegration and extend the useful lifetime of the implants. The surface properties of the Ti6Al7Nb alloys of the hip-stem endoprostheses (30 retrieved and 2 new) were determined by contact-angle measurements and the average surface roughness. The surface chemistry and microstructure were analysed by scanning electron microscopy (SEM) for morphology, energy-dispersive X-ray spectroscopy (EDS) for the chemistry, and electron back-scatter diffraction (EBSD) for the phase analysis; Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) for the surface chemistry; and electrochemical measurements for the corrosion. The improved wettability of the grit-blasted surface of the Ti6Al7Nb stems after autoclaving was measured, as was the super wettability after oxygen-plasma sterilization. The secondary-electron images showed that the morphology and microstructure of the new and retrieved stems (prematurely failed due to aseptic loosening, infection and latent infection) differ slightly, while the EDS analysis revealed corundum contamination of the grit-blasted surface. We found corundum-contaminated Ti6Al7Nb stem surfaces and sub-surfaces for all the investigated new and retrieved implants. These residues are a potential problem, i.e., third-body wear particles, and probably induce the osteolysis and aseptic loosening.
The aim of this study was to find the optimal basketball athletic stance which will enable the fastest subsequent action. We compared the reaction (RT), movement (MT), and total response (RST) times ...of a single leg lateral step, performed from starting positions and differentiating in three different heights and two different stance widths. RMANOVA results showed that the RSTs obtained during wide stance positions were clearly shorter when compared to the times obtained during narrow stances (p = 0.000). Interaction of the height (knee angle) and width of stance was also found significant (p = 0.048), while the effect of the height of the stance alone was not (p = 0.098). Similar results were found for MT, while no differences were found for RT. Width of the stance therefore clearly brings about different RSTs; a wide feet position enabled shorter MT when compared to a narrow position and consequently shorter RST, probably due to a more advantageous starting position for lateral movements and due to laws of joint and muscle mechanics. The basic athletic stance with feet double shoulder distance apart and a medium (120°) and small (150°) knee flexion was found optimal in enabling the quickest lateral movement response.
Following the finding that ammodytoxin (Atx), a neurotoxic secreted phospholipase A.sub.2 (sPLA.sub.2) in snake venom, binds specifically to protein disulfide isomerase (PDI) in vitro we show that ...these proteins also interact in living rat PC12 cells that are able to internalize this group IIA (GIIA) sPLA.sub.2 . Atx and PDI co-localize in both differentiated and non-differentiated PC12 cells, as shown by fluorescence microscopy. Based on a model of the complex between Atx and yeast PDI (yPDI), a three-dimensional model of the complex between Atx and human PDI (hPDI) was constructed. The Atx binding site on hPDI is situated between domains b and b'. Atx interacts hPDI with an extensive area on its interfacial binding surface. The mammalian GIB, GIIA, GV and GX sPLA.sub.2 s have the same fold as Atx. The first three sPLA.sub.2 s have been detected intracellularly but not the last one. The models of their complexes with hPDI were constructed by replacement of Atx with the respective mammalian sPLA.sub.2 in the Atx-hPDI complex and molecular docking of the structures. According to the generated models, mammalian GIB, GIIA and GV sPLA.sub.2 s form complexes with hPDI very similar to that with Atx. The contact area between GX sPLA.sub.2 and hPDI is however different from that of the other sPLA.sub.2 s. Heterologous competition of Atx binding to hPDI with GV and GX sPLA.sub.2 s confirmed the model-based expectation that GV sPLA.sub.2 was a more effective inhibitor than GX sPLA.sub.2, thus validating our model. The results suggest a role of hPDI in the (patho)physiology of some snake venom and mammalian sPLA.sub.2 s by assisting the retrograde transport of these molecules from the cell surface. The sPLA.sub.2 -hPDI model constitutes a valuable tool to facilitate further insights into this process and into the (patho)physiology of sPLA.sub.2 s in relation to their action intracellularly.
PDF
