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Aims Calcium dyshomeostasis is implicated in the pathogenesis of several neurodegenerative disorders including Alzheimer's disease. However, much of the previous research has focused on changes in neuronal calcium signalling. In a recent microarray study we identified dysregulation of several key signalling pathways including the Ca2+ signalling pathway in astrocytes as Alzheimer-type pathology developed. In this study we sought to determine the expression of calpain-10 and calcium/calmodulin-dependent kinase alpha (CamKIIα) in relation to Alzheimer-type pathology in a population-based study. Methods Using post mortem temporal cortex samples derived from the Medical Research Council Cognitive Function and Ageing Study (MRC-CFAS) ageing brain cohort we examined calpain-10 and CamKIIα gene and protein expression using quantitative polymerase chain reaction and immunohistochemistry. Results We demonstrate that astrocytic expression of calpain-10 is up-regulated, and CamKIIα down-regulated with increasing Braak stage. Using immunohistochemistry we confirm protein expression of calpain-10 in astrocytes throughout the temporal cortex and demonstrate that calpain-10 immunoreactivity is correlated with both local and global measures of Alzheimer-type pathology. In addition, we identify a subpopulation of calpain-10 immunoreactive interlaminar astrocytes that extend processes deep into the cortex. CamKIIα is predominantly neuronal in localization and is associated with the presence of diffuse plaques in the ageing brain. Discussion Dysregulated expression of key calcium signalling molecules occurs with progression of Alzheimer-type pathology in the ageing brain, highlighting the need for further functional studies of astrocytic calcium signalling with respect to disease progression.

Die Entwicklung des thermischen Beschichtens als eine der Schlusselindustrien des 21. Jahrhunderts wird auch zukunftig besonders vom Kostendruck getrieben werden. Die Moglichkeit zur Herstellung qualitativ hochwertiger Schichten erfordert ein vertiefendes Verstandnis in allen Abschnitten des Beschichtungsprozesses. Den Eigenschaften der Gasstromung im Bereich des Ausganges des Flammengenerators kommt hierbei eine grose Bedeutung zu, wenn die Reproduzierbarkeit der gespritzten Schichten erhoht und dadurch eine Kostenreduktion erreicht werden soll. Die Optimierung der Injektionsbedingungen verschiedenster Pulver ist Ziel der Forschung. Diese Arbeit stellt ein robustes ruckwirkungsfreies optisches Diagnostikverfahren fur schnelle Gasstromungen vor, welches auf der Auswertung dopplerverschobenen gestreuten Laserlichts beruht. Zur Validierung des Verfahrens wurde eine Uberschallduse von bekannter Mach-Zahl konstruiert und mit dem etablierten Particle Imaging Velocimetry (PIV) Verfahren der Stromungsmechanik vermessen. Thermal spraying, as one of the key industries of the 21st century, is being developed particularly due to its potential in reducing production costs. The possibility of a deposition of high quality coatings requires a deep knowledge of each step involved in the spraying process. One important factor are the properties of the gas flow close to the outlet of the flame generator, if the reproducibility of the sprayed coatings is to be achieved, as well as their production cost reduction. The optimisation of the injection parameters for different powders is the main object of this work. This paper presents a robust contact-less optical diagnostic technique for high velocity gas flows, based in the measurement of the Doppler shift of scattered laser light. Additionally, in order to validate these measurements, a supersonic nozzle of known Mach number at outlet has been designed and measured with the well established particle imaging velocimetry technique.

The developing field of community genetics has the potential to broaden the contribution of genetics to conservation biology by demonstrating that genetic variation within foundation plant species can act to structure associated communities of microorganisms, invertebrates, and vertebrates. We assessed the biodiversity consequences of natural patterns of intraspecific genetic variation within the widely distributed Australian forest tree, Eucalyptus globulus.We assessed genetic variation among geographic races of E. globulus (i.e., provenances, seed zones) in the characteristics of tree-trunk bark in a 17-year-old common garden and the associated response of a dependent macroarthropod community. In total, 180 macroarthropod taxa were identified following a collection from 100 trees of five races. We found substantial genetically based variation within E. globulus in the quantity and type of decorticating bark. In the community of organisms associated with this bark, significant variation existed among trees of different races in composition, and there was a two-fold difference in species richness (7–14 species) and abundance (22–55 individuals) among races. This community variation was tightly linked with genetically based variation in bark, with 60% of variation in community composition driven by bark characteristics. No detectable correlation was found, however, with neutral molecular markers. These community-level effects of tree genetics are expected to extend to higher trophic levels because of the extensive use of tree trunks as foraging zones by birds and marsupials. Our results demonstrate the potential biodiversity benefits that may be gained through conservation of intraspecific genetic variation within broadly distributed foundation species. The opportunities for enhancing biodiversity values of forestry and restoration plantings are also highlighted because such planted forests are increasingly becoming the dominant forest type in many areas of the world.

Coating production by thermal plasma spray is dependent on the residence time of particles in the plasma jet produced by the gas flow inside a plasma torch. To ensure a high fraction of well-molten particles to be accelerated towards the substrate a long reproducible residence time is needed. This can be achieved by a long plasma jet with little or no temporal variation in length and temperature. While single electrode plasma torches need an unstable attachment of the anodic arc root in order to avoid excess erosion, which also causes an unstable plasma jet, multi-electrode torches allow operation with fixed anode attachments by subdividing the anode current by the number of electrodes used, and thereby thus reducing the power input for each separated arc root. Once the steady anode attachment has been obtained the produced plasma jet exhibits a steady characteristic, but also looses rotational symmetry. The separation can be achieved by using either multi anode or multi cathode geometry with appropriate electrical control. Both version have been produced with 3 electrodes each resulting in two systems known as the Delta Gun (3 anodes) and Triplex (3 cathodes). (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

White matter lesions (WML) on magnetic resonance imaging (MRI) brain scans are associated with ageing. They are unrelated to specific disorders, and their impact on cognitive and other brain functions is poorly characterized. Pathological studies often omit systematic survey of WML because of the need to study multiple full coronal tissue blocks, and uncertainty over the significance of lesions identified in periventricular and deep subcortical regions. Post-mortem MRI provides a means of mapping WML but the sensitivity and specificity of the method are unresolved. In this study post-mortem MRI of WML in fixed brain slices was compared with pathology in 33 brains donated to the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS). This study shows that MRI detection of WML was less sensitive than pathology: periventricaular lesions (PVL) sensitivity = 95% (87-99%), specificity = 71% (44-90%); deep subcortical lesions (DSCL) sensitivity = 86% (79-93%), specificity = 80% (72-88%). False negative MRI was associated with milder pathology, but lesions detected by myelin attenuation alone showed both microglial and endothelial activation. Therefore post-mortem MRI of formalin-fixed brain slices is a reliable method to obtain systematic data on the severity and distribution of cerebral white matter disease, and appears to detect those WML most likely to have clinical impact.

We have investigated the correlation between urinary isatin concentration and MAO-B inhibitory activity. A sensitive enzyme-linked immunosorbent assay (ELISA) for the measurement of isatin in urine was developed. There was a strong correlation between isatin concentrations determined by this method and the established GC/MS technique. In two sets of urine samples from healthy individuals (N = 63 and N = 21), we have shown that there is no significant correlation between isatin concentration and MAO-B inhibitory activity (r = − 0.1013 and − 0.1597, respectively). Based upon IC50 measures, the concentration of isatin in normal urine (N = 10) was 3– 5 times less than that which could account for the detected MAO-B inhibitory activity. Furthermore, Lineweaver-Burk plots from urine samples (N = 12) compared with isatin showed that the inhibition by isatin was competitive whereas urine samples could elicit either mixed or non-competitive inhibition. We conclude that the MAO-B inhibitory activity in urine cannot be attributed to isatin alone and another inhibitor(s) appears to be present.