Congo red stain

Spatially confined self-assembly has been further confirmed by localizing ther-molysin on certain areas of a PEGylated surface. Upon immersion of this modified surface into a solution containing self-assembling precursors, nanostructures were formed in the vicinity of the enzyme, as observed through congo-red staining (Fig. 7c) [21]. Thus, enzyme-assisted self-assembly allows for construction of supramolecular polymers with spatiotemporal control, i.e. where and when they are required. 

Mycelial mats of the selected 35 strains and the original strain were incubated on the medium for estimation of cellulase productivity for 6 d at 28°C in order to compare cellulase productivity. After Congo red staining, strain Cll, showed the highest cellulase productivity. Moreover, the cellulase productivity of strain Cll was compared with that of the original strain using 18 agar plates of the medium for estimation of cellulase productivity. After incubation, strain Cll showed superior cellulase productivity, as shown in Fig. 2 and Table 2. Thus, strain Cll was selected as a cellulase hyperproducer. 

Carder, J. H., Detection and quantitation of cellulase by Congo red staining of substrates in a cup-plate diffusion assay. Anal Biochem 1986, 153 (1), 75-9. 

Hemorrhage into brain tissue has many causes and often accompanies other lesions within the CNS. The major role of IHC is to identify certain causes of hemorrhage such as amyloid and neoplasm. Amyloid angiopathy is a common cause of spontaneous intracerebral hemorrhage in the elderly (see Table 20.3). Immunohis-tochemical staining with an antibody to 3/A4 protein is more sensitive than Congo red stain in demonstrating the extent of vascular amyloid." ... 

Howie, A. J. Brewer, D. B. Howell, D. Jones, A. P. Physical basis of colors seen in congo red-stained amyloid in polarized light. Lab. Invest. 2008, 88, 232-242. 

This is an extracellular deposition of an insoluble protein, which has adopted a (3-sheet structure due to an unknown event that induced misfolding of unstable proteins. The name amyloid has been given according to the amyloid staining properties, which are similar to carbohydrate deposits, e.g., amyloid can be identified with Congo red and seen under polarized light (birefringence test). 

Wolman, M., and Bubis, J. J. (1965). The cause of the green polarization color of amyloid stained with Congo red. Histochemie 4, 351-356. 

Congo red org chem C32H22N5Na205S2 An azo dye, sodium diphenyldiazo-bis-a-naphthylamine sulfonate, used as a biological stain and as an acid-base indicator it is red in alkaline solution and blue in acid solution. kag-go red ... 

The demonstration of amyloid protein in a tissue biopsy specimen by staining with Congo red and examination by polarized light microscopy is required for a definitive diagnosis. 

It has been reported that crystallinity and accessibility to moisture do not change after enzymatic hydrolysis. Techniques employing light microscopy and staining of fibers with Congo Red can be used to determine the location of enzymatic attack for cotton and linen. 

Figure 43.1. Compacted paienchymal amyloid plaque in APP trai gaiic mouse liippocampus. Section was stained witli Congo red and viewed witli aoss-polaiized liglit. Total magnificadon x 400.

Figure 43.1. Compacted parenchymal amyloid plaque in APP transgenic mouse hippocampus. Section was stained with Congo red and viewed with cross-polarized light. Total magnification x 400.

---