Histochemical

A. Engstrom, Quantitative Micro- and Histochemical Elementary Analysis by Roentgen Absorption Spectrography, Acta Radiol. Suppl, 63 (1946). 

NADPH-diaphorase activity is the ability of an enzyme to reduce soluble tetrazolium salts to an insoluble, visible formazan. This activity is being used by many laboratories to localize NO synthase histochemically. 

Although clinical examination provides important clues to diagnosis of congenital myopathies, ultrastructural and histochemical examination of muscle biopsies provides the key to definitive identification. Most of the congenital myopathies... 

Histopathological features are dominated by the large number of centrally-placed muscle nuclei, sometimes affecting more than 90% of muscle fibers. The nuclei form long chains in the middle of the fiber and are surrounded by cytoplasm, which contains mitochondria and membranous vesicles, but no myofibrils. This morphological appearance has prompted comparison with myotubes, and in fact centronuclear myopathies are sometimes referred to as myotubular myopathies. This is a misnomer, however, since although the affected fibers retain some of the structural features of myotubes, and maturational arrest may play a role in their formation, the vast majority of such fibers are fully differentiated histochemically into either type 1 or type 2. 

Centronuclear myopathy with type 1 fiber hypotrophy is sometimes regarded as a separate entity because many cases show central nuclei only in the hypotrophic type 1 fibers, while the type 2 fibers are morphologically normal. Affected type 1 fibers are even more myotubelike than in other variants of the disorder, with the exception of the severe X-linked form, due to the persistence of a mitochondria-rich core within a peripheral ring of myofibrils. These features are clearly demonstrable using histochemical methods for the localization of SDH activity and myofibrillar ATPase, respectively. 

From the practical viewpoint it is important to be able to distinguish infants and children with this condition from less benign disorders such as the spinal muscular atrophies. Careful histochemical assessment of muscle biopsies with histographic analysis is recommended. Most biopsies from CFTD patients show type 1 fibers which are small in relation to type 2 fibers. A revised definition of CFTD states that... 

Glycogenosis type VIII (phosphorylase b kinase deficiency) gives rise to myopathy and liver disease, either singly or in combination. Phosphorylase b kinase (PBK) converts the inactive b form of both muscle and liver phosphorylases to the active a forms of the enzymes. The ischemic lactate test sometimes shows a flat result as in McArdle s disease, but is more likely to be normal. Histochemical demonstration of myophosphorylase activity in tissue sections shows a near-normal reaction due to the presence of phosphorylase a. Accumulation of glycogen is modest and found mainly in type 2 (fast-twitch glycolytic) muscle fibers. 

Figure 15. Grouping of muscle fibers of uniform histochemical type indicating reinnervation in a patient with SMA.

Muscle biopsy with full histochemical and ultrastructural investigation is necessary for the confirmation of a diagnosis of IBM. The inclusions which are the hallmark of this disorder are to be found in three locations (a) basophilic granular inclusions are found at the periphery of vacuoles within the cytoplasm of muscle fibers (b) eosinophilic hyaline inclusions are also found in the cytoplasm but are not associated with vacuoles and (c) intranuclear inclusions consisting of aggregates of filamentous microtubules are found in a variable percentage of muscle nuclei. Inclusions of the first two types are visible at light microscope level, whereas the third type is detectable at the electron microscope level only. Ultrastructural... 

Figure22. (a) Euthyroid(normal)ratmuscleshowingmixtureoftype1 (slow-twitch) and type 2 (fast-twitch) fibers, (b) Hypothyroid rat muscle showing uniformly type 1 (slow-twitch) histochemical profile myofibrillar ATPase after alkaline preincubation.

Hahn T, Ruhnke M, Luppa H. 1991. Inhibition of acetylcholinesterase and butyrylcholinesterase by the organophosphorus insecticide methyl parathion in the central nervous system of the golden hamster i Mesocricetus aumtus). Acta Histochem (Jena) 91 13-19. 

Crevecoeur M. Pinedo M. Greppin H. Penel C. (1997) Peroxodase activity in shoot apical meristem from Spimcia / / Acta Histochem. V. 99(2). P. 177-186. 

The polyene macrolide filipin was isolated in 1955 from the cell culture filtrates of Sterptomyces filipinensis, and was later shown to be a mixture of four components [36]. Although too toxic for therapeutic use, the filipin complex has found widespread use as a histochemical stain for cholesterol and has even been used to quantitate cholesterol in cell membranes [37]. The flat structure of filipin III, the major component of the filipin complex, was assigned from a series of degradation studies [38]. Rychnovsky completed the structure determination by elucidating the relative and absolute stereochemistry [39]. The total synthesis plan for filipin III relied heavily on the cyanohydrin acetonide methodology discussed above. 

Nitrophenyl esters of thymidine are substrates for staphylococcal nuclease and ribonucleotide 5 -(5-iodoindol-3-ol) (3) and 5 -(4-methyl-coumarin-7-ol) (4) esters have been used for the histochemical demon-... 

BONTOUX L (2001) The European strategy on endocrine disrupters progress to date and EU/US cooperation. Folia Histochem Cytobiol. 39 (Suppl 2) 9-11. 

RozemuUer, J.M., Eikelenboom, P., Kamphorst, W. and Stam, F.C. (1988). Lack of evidence for dysfunction of the blood-brain barrier in Alzheimer s disease an immuno-histochemical study. Neurobiol. Aging 9, 383-391. 

LR white embedding allows a multi-method approach to the analysis of brain tissue from patients with Alzheimer s disease. Histochem. J. 22, 257-268. 

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