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Spinal Cord Disease
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Inherited leukodystrophies: Adrenoleukodystrophy (ALD)/adrenomyeloneuropathy (AMN).Metachromatic leukodystrophy.Krabbe's (globoid cell) leukodystrophy.
Cystic Fibrosis
Published in Stephen D. Litwin, Genetic Determinants of Pulmonary Disease, 2020
Alexander G. Bearn, Β. Shannon Danes
Studies on metachromasia hint at genetic heterogeneity. In the majority of CF patients and obligatory heterozygotes studied cellular metachromasia was observed. However, in those few patients in whom metachromasia could not be detected either with toluidine blue O or alcian blue, no metachromasia was detected among their parents who are obligatory heterozygotes [51]. It was of interest that studies in tissue culture also suggested that these patients with CF in whom metachromasia was not apparent and did not demonstrate the ciliary inhibitory factor in cell culture had a poorer prognosis [52,53]. In a study on 131 Danish CF patients [54] and their families, it was found that (1) the initial diagnosis was made earlier in patients whose cultures did not show either metachromasia or cystic fibrosis factor activity, (2) only 5% of such patients survived over the age of 15 years, whereas 24% of those patients with metachromatic CFF positive cultures were over age 15 years at the end of the study (Fig. 2).
Sly disease/β-glucuronidase deficiency/mucopolysaccharidosis VII
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
Coarse lamellar Alder-Reilly inclusions are seen in peripheral granulocytes [1, 31,32] and also in the bone marrow. Pathologic examination has revealed vacuolated hepatocytes; electron microscopy has shown cytoplasmic membrane-bound vesicles [18]. The stored material stains with alcian blue, and this staining may be seen in cultured fibroblasts, which also display metachromasia.
Systematic review of accuracy of reporting of Congo red-stained amyloid in 2010–2020 compared with earlier
Published in Annals of Medicine, 2022
Alexander J. Howie, Mared P. Owen-Casey
The birefringence of Congo red-stained amyloid is shown by the appearance of brightness against a dark background when the specimen is examined between crossed analyser and polariser [1–5]. Eight papers incorrectly said that there was green dichroism. Dichroism is shown with either an analyser or a polariser, but not both, and means that a material absorbs some wavelengths of light polarised in one direction of orientation of the material, and so appears a particular colour, red in the case of Congo red-stained amyloid, but does not absorb light polarised at right angles, and so the material appears in theory colourless, but in practice a lighter shade of the same colour, still red in this case [3]. Three papers used the term green metachromasia when talking about polarised light, but metachromasia means that there is a change of colour when a dye is examined in ordinary, unpolarised light [5]. Two papers used the term green fluorescence in polarised light, but fluorescence means emission of longer wavelengths, usually in the visible spectrum, than the illuminating wavelengths, usually ultraviolet radiation.
Tissue biopsy for the diagnosis of amyloidosis: experience from some centres
Published in Amyloid, 2022
Merrill D. Benson, John L. Berk, Angela Dispenzieri, Thibaud Damy, Julian D. Gillmore, Bouke P. Hazenberg, Francesca Lavatelli, Maria M. Picken, Christoph Röcken, Stefan Schönland, Mitsuharu Ueda, Per Westermark
Although Congo red is used in most situations for the recognition of amyloid at microscopy, as mentioned it is not a stain without problems. The affinity for the dye varies strongly between, and sometimes within the different forms of amyloid. When the affinity is low, the resulting birefringence is also weak and can be difficult to discern. Therefore, some laboratories use additional stains, particularly for screening purposes. The old metachromatic stains, such as cresyl violet, are rarely used by specialised laboratories. Alternatives are the Congo-red derived molecule (E,E)-1-fluoro-2,5-bis(3-hydroxycarbonyl-4-hydroxy) styrylbenzene (FSB), giving amyloid a strong fluorescence, or alcian blue, binding to the always present glycosaminoglycans. These two stains are used by some specialised laboratories. Finally, there are additional fluorescent ligands such as luminescent conjugated oligothiophenes (LCOs) with very promising properties but these are mainly yet used for research.
Synthesis and structure-activity relationships of cerebroside analogues as substrates of cerebroside sulphotransferase and discovery of a competitive inhibitor
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Wenjin Li, Joren Guillaume, Younis Baqi, Isabell Wachsmann, Volkmar Gieselmann, Serge Van Calenbergh, Christa E. Müller
Metachromatic leukodystrophy (MLD) is a rare genetic disease characterised by a dysfunction of the enzyme arylsulphatase A1. This defect leads to the lysosomal accumulation of cerebroside sulphate (sulphatide, 1) in various cells such as tubular kidney cells, bile duct epithelia, some neurons, oligodendrocytes and Schwann cells. In particular accumulation in the latter two results in progressive demyelination finally causing lethal symptoms in patients. Recently haematopoetic stem cell-based gene therapy has been shown to be effective in patients in early preclinical states of disease only2. Thus, there is an urgent need to develop alternative strategies to treat MLD. One of these strategies is substrate reduction therapy in which galactosylceramide (cerebroside) sulphotransferase (CST; EC 2.8.2.11), the enzyme which synthesises sulphatide, is inhibited. This would diminish the load of accumulated sulphatide in the patient. Such a strategy has been shown to be effective in Gaucher disease, another lysosomal sphingolipid storage disorder3. Inhibition of galactosylceramide sulphotransferase has been proposed as a promising new therapeutic strategy for the treatment of MLD1,4. CST catalyses the transfer of a sulphate group from the coenzyme 3′-phosphoadenosine-5′-phosphosulphate (PAPS, 2) to galactosylceramide (3) yielding galactosylceramide sulphate (2) and adenosine-3′,5′-bisphosphate (PAP, 4) (Figure 1)5–7.