Avoidance of precipitation and carbohydrate breakdown in autoclaved plant tissue culture media

The extent of breakdown of fructose and glucose derived from sucrose in the medium of Murashige and Skoog (1962) during autoclaving was investigated by polarographic measurement. Although not present in the original MS medium but often used in place of FeSO₄ + Na₂-EDTA, FeNa-EDTA was found to be primarily responsible for catalyzing the breakdown of these monosaccharides. It would therefore be good practice to autoclave FeNa-EDTA separate from the carbohydrate constituents of the medium in order to reduce the formation of toxic substances derived from the latter's breakdown. Autoclaving FeNa-EDTA separately has the additional advantage of preventing precipitation of certain micronutrient elements. Further precipitation can be avoided by autoclaving FeNa-EDTA and KH₂PO₄ together, but separately, from other components of the medium. By eliminating precipitation and minimizing the breakdown of monosaccharides during autoclaving, it is possible to improve the quality of the medium without resorting to sterilization by filtering.Abbreviations HMF 5-(hydroxymethyl)-2-furaldehyde - FeNa-EDTA ferric monosodium ethylenediaminetetraacetic acid - MS Murashige and Skoog - NAA naphthylacetic acid     

Staining Problems with Eosin Y: A Note from the Biological Stain Commission

In 1980, eosin Y was the certified dye with which technologists encountered most problems. The specific problem most frequently brought to the attention of the Biological Stain Commission was that solutions of eosin Y formed a precipitate and failed to stain cytoplasm red when used as a counterstain to hematoxylin.     

Colour development of immunogold-labelled antibodies for light microscopy

We describe an improvement of the immunogold technique, which is based on the colour development of silver-intensified immunogold signals. This method (referred to as the coloured-SIG technique) was found to be as sensitive as the silver-intensified immunogold method and more sensitive (in two of the three tested systems) than immunoenzymatic procedures, such as the peroxidase/antiperoxidase technique or the avidin-biotin system. The coloured SIG-method results in either a magenta-red or a cyan-blue final reaction product. Therefore, this new improvement of the immunogold technique should be useful in double-staining methods, immunoblot methods and conventional immunostaining methods.     

CYR61/CCN1 and WISP3/CCN6 are chemoattractive ligands for human multipotent mesenchymal stroma cells

Background:  

CCN-proteins are known to be involved in development, homeostasis and repair of mesenchymal tissues. Since these processes implicate recruitment of cells with the potential to be committed to various phenotypes, we studied the effect of CYR61/CCN1 and WISP3/CCN6 on migration of human bone marrow derived mesenchymal stroma cells (MSCs) in comparison to in vitro osteogenic differentiated MSCs using a modified Boyden chamber assay.