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Notes: Abstract Confocal fluorescence microscopy enables visualisation and quantitation of fluorescent probes at high resolution deep within intact tissues, with minimal disturbance both of cell–cell interactions and the mechanical, ionic and physiological effects of the extracellular matrix. We illustrate the principles of multiple-parameter 3-D (x,y,z) imaging using reconstruction of nuclear channels in mammalian cells. Repeated sampling in time generates 4-D (x,y,z,t) images which can be used to follow dynamic changes, such as blue-light-dependent chloroplast re-orientation, in intact tissues. Quantitative measurements from multi-dimensional images require calibration of the spatial dimensions of the image and the fluorescence intensity response. This must be determined throughout the volume, which must be sampled to correct for geometric distortion as well as photometric errors arising from the complete optical system, including the specimen. The effects of specimen calibration are illustrated for morphological analysis of stomatal closing responses to abscisic acid in Commelina from 4-D images. Calibrated 4-D imaging allows direct volume measurements and we have followed volume regulation of chondrocytes in cartilage explants during osmotic perturbation. In intact cartilage, unlike in isolated cells, the chondrocytes exhibit volume regulatory mechanisms. In other cases, the fluorescence intensity of the probe may be related to a physiological parameter of interest and changes in its distribution within the cell. Optical sectioning permits discrimination of signal in separate compartments within the cell and can be used to follow transport events between different organelles. We illustrate 3-D (x,y,t) measurements of vacuolar glutathione conjugate pump activity in intact roots of Arabidopsis by following the sequestration of a fluorescent conjugate between glutathione and monochlorobimane. Dynamic measurements of protein localisation are now possible following the introduction of chimeric fusion proteins with green fluorescent protein (GFP) from Aequoria victoria. We have analysed the disposition of heterochromatin in nuclei of living Schizosaccharomyces pombe cells expressing a chimeric construct between Swi6 and GFP. Heterochromatin dynamics can be followed throughout mitosis in 4-D (x,y,z,t) images. Statistical analysis of the fluorescence histograms from each nucleus over time provides quantitative support for aggregation and dispersion of Swi6-GFP clusters during mitosis, rather than dissociation of Swi6 from the heterochromatin. A wide range of single-wavelength and ratio probes are available for imaging different ion activities. We compare 3-D (x,y,t) measurements of ion activities made using single-wavelength (Fluo-3 for calcium) and ratio (BCECF for pH) measurements, using stomatal responses in Vicia faba to peptides from the auxin-binding protein of maize and tip growth in pollen tubes of Lilium longiflorum as examples. Ratioing techniques have many advantages for quantitative fluorescence measurements and we conclude with a discussion of techniques to develop ratioing of single-wavelength probes against alternative references, such as DNA, protein or cell wall material.

Notes: Abstract  The application of glass in the microsystems technology becomes more and more important. Therefore, it is necessary to combine special microstructurable glasses with various other materials (e.g. joining with silicon by anodic bonding, joining with metals by electroforming, joining with polymers by glueing, joining with various other glasses by brazing or diffusion welding). In order to increase the use of glass in the microsystems technology especially four fields of research are important: –development of special glasses with various properties –technologies of microstructuring –technologies of joining –application These four topics are main research fields performed at the Institute of Glass/Ceramics-Technology and will be described in this paper.

Notes: [Auszug] SirThe first genetically modified (GM) crops being proposed for commercial planting in the United Kingdom have been altered to make them less sensitive to broad-spectrum herbicides. These crops are intended to allow more efficient weed management and herbicide regimes for the ...

Notes: [Auszug] The UK Farm-Scale Evaluations (FSE) compared the effects on biodiversity of management of genetically modified herbicide-tolerant (GMHT) spring-sown crops with conventional crop management. The FSE reported larger weed abundance under GMHT management for fodder maize, one of three crops ...

Notes: Aims : To determine whether chorioamnionitis has an impact on the extent of apoptosis and proliferation in fetal lungs. Fetuses exposed to chorioamnionitis have an increased risk of aquiring lung tissue damage in utero.Methods and results : Lung tissue sections from 35 stillborn fetuses were used in this study. Chorioamnionitis-exposed fetuses were subdivided depending on whether pneumonia was diagnosed (n = 13) or not (n = 10); 12 unaffected fetuses served as controls. Apoptotic and proliferating cells were determined by in-situ terminal deoxytransferase-mediated dUTP nick end labelling (TUNEL) assay and by anti-Ki67 immunohistochemistry, and quantified. The median apoptotic index in lungs of chorioamnionitis-exposed fetuses increased 2.4-fold compared with chorioamnionitis-negative stillborn controls (P = 0.043) and rose 21.6-fold when chorioamnionitis-exposed fetuses additionally developed pneumonia (P 〈 0.001). Compared with the proliferation index of the control group (PI =2.3), the median percentage of proliferating cells in the lungs of chorioamnionitis-exposed fetuses decreased (PI = 1.4) (P = 0.036), but increased 1.8-fold (P = 0.036) in fetal lungs of the chorioamnionitis/pneumonia group. By double labellings combining the TUNEL assay or the Ki67 antigen with cell marker proteins, we identified distal airway epithelial cells as the cell type undergoing apoptosis in chorioamnionitis-exposed fetal lungs, while epithelial, endothelial and smooth muscle cells proliferated. Immunolabellings of cleaved caspases -8 and -9 revealed that apoptosis is mediated via initiator caspase-8.Conclusion : Chorioamnionitis induces apoptosis of distal airway epithelial cells via the caspase-8 pathway and interferes with the normal proliferative activity of epithelial, endothelial, and smooth muscle cells in fetal lungs. Thus, apoptosis and proliferation are an important feature of chorioamnionitis-associated lung injury in utero.