Domain analysis of lipoprotein LppQ in Mycoplasma mycoides subsp. mycoides SC

The lipoprotein LppQ is the most prominent antigen of Mycoplasma mycoides subsp. mycoides small colony type (SC) during infection of cattle. This pathogen causes contagious bovine pleuropneumonia (CBPP), a devastating disease of considerable socio-economic importance in many countries worldwide. The dominant antigenicity and high specificity for M. mycoides subsp. mycoides SC of lipoprotein LppQ have been exploited for serological diagnosis and for epidemiological investigations of CBPP. Scanning electron microscopy and immunogold labelling were used to provide ultrastructural evidence that LppQ is located to the cell membrane at the outer surface of M. mycoides subsp. mycoides SC. The selectivity and specificity of this method were demonstrated through discriminating localization of extracellular (i.e., in the zone of contact with host cells) vs. integral membrane domains of LppQ. Thus, our findings support the suggestion that the accessible N-terminal domain of LppQ is surface exposed and such surface localization may be implicated in the pathogenesis of CBPP

Induction of cytochrome P450 enzymes in primary equine hepatocyte culture

In this study, we established cell culture conditions for primary equine hepatocytes allowing cytochrome P450 enzyme (CYP) induction experiments. Hepatocytes were isolated after a modified method of Bakala et al. (2003) and cultivated on collagen I coated plates. Three different media were compared for their influence on morphology, viability and CYP activity of the hepatocytes. CYP activity was evaluated with the fluorescent substrate 7-benzyloxy-4-trifluoromethylcoumarin. Induction experiments were carried out with rifampicin, dexamethasone or phenobarbital. Concentration-response curves for induction with rifampicin were created. Williams' medium E showed the best results on morphology and viability of the hepatocytes and was therefore used for the following induction experiments. Cells cultured in Dulbecco's Modified Eagle Medium were not inducible. Incubation with rifampicin increased the CYP activity in two different hepatocyte preparations in a dose dependent manner (EC50=1.20 μM and 6.06 μM; Emax=4.1- and 3.4-fold induction). No increase in CYP activity was detected after incubation with dexamethasone or phenobarbital. The hepatocyte culture conditions established in this study proved to be valuable for investigation of the induction of equine CYPs. In further studies, other equine drugs can be evaluated for CYP induction with this in vitro system

Expression and morphology of enterotoxigenic Escherichia coli surface antigen CS31A in E. coli K12 and Vibrio cholerae

Enterotoxigenic Escherichia coli (ETEC) is known as a worldwide cause of diarrheal disease. The pathogenesis involves the attachment of the microorganisms to the mucosa and the production of enterotoxins. Surface expression of CS31A fimbriae was assessed by Western blots, dot blots, immunofluorescence, and electron microscopy using negative staining and immunogold labeling. These investigations revealed significant differences in both the morphology of the wild-type and recombinant strains and the antigen exposure of CS31A in the wild-type and recombinant strains. In the wild-type ETEC strain, expression of CS31A was subject to phase variation. The recombinant E. coli strain produced CS31A but was prone to epitope shedding. In Vibrio cholerae vaccine strain CVD 103-HgR, the recombinant CS31A antigen was expressed but was only found intracellularly. Thus, E. coli strains seem to lend themselves better to the development of recombinant vaccines expressing ETEC-specific antigens at the cell’s surface than strains from other orders or genera such as V. cholerae.</jats:p

The Geology of Switzerland

The general picture of the physiographic map of Switzerland reflects the tectonic structure rather directly. Local relief in the Jura Mountains is a direct consequence of folding of the detached Mesozoic strata. The Swiss Plateau mimics the Molasse Basin with flat lying sediments while thrusting and tilting of these strata in the Subalpine Molasse amalgamated these units with the Alps. The Alps exhibit nappe stacks of very different origin. Most of them evolved from pre-Triassic crystalline basement rocks and their sedimentary cover. In many cases the cover was detached from its basement and now forms a nappe stack of its own. The Helvetic nappe system derived from the European continental margin contains nappes of cover rocks displaced over 30–50 km; crystalline basement rocks form large-scale domes. The Penninic nappe system is derived from basins that formed in Mesozoic times between the European and Adriatic continents. They contain far travelled nappes of cover rocks, as well as nappes of basement rocks that were transported over considerable distances, too. In addition, nappes of oceanic rocks outcrop as thin slivers at the top. Post-nappe folding within the Penninic nappe stack is reminiscent of their complex formation history. The Austroalpine nappe system was derived from the Adriatic margin and now forms a horizontal layer as the highest unit in eastern and central Switzerland. This nappe system contains crystalline basement as well as Mesozoic cover rocks and was emplaced early in the Alpine history in a ENE direction. The Southalpine nappe system was derived from the Adriatic margin as well. Here thrusting of crystalline basement with its Mesozoic cover was south-directed. The various Alpine nappe piles led to the amalgamation of very different rock types: continental and oceanic basement rocks, shallow marine carbonates, deep marine clastics and radiolarian chert to name the most important. Landforms and landscapes reflect these differences, in addition to the landforms created by fluvial and glacial erosion

Special National Intelligence Estimate Number 13-4-63 Possiblities of Greater Militancy by the Chinese Communists

Special National Intelligence Estimate Number 13-4-63 Possiblities of Greater Militancy by the Chinese Communist

Study of a V-shape flame based on IR spectroscopy and IR imaging

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