Differential muscle

Shields, D.C., Schaecher, K.E., Saido, T.C., Banik, N.L., 1999, A putative mechanism of demyelination in multiple sclerosis by a proteolytic enzyme, calpain, Proc. Natl. Acad. Sci. USA 96,11486-11491 Shollmeyer, J., 1986, Possible role of calpain I and calpain II in differentiating muscle, Exp. Cell. Res., 163, 413 122... 

G. Ferrari, G. Salvatori, C. Rossi, G. Cossu, and F. Mavilio, A retroviral vector containing a muscle-specific enhancer drives gene expression only in differentiated muscle fibers, Hum. Gene Ther. 6 733 (1995). 

The patterns of several sets of isoenzymes change during normal development in tissues from many species. For example, changes in the relative proportions of several isoenzymes are noted during the embryonic development of skeletal muscle. The proportions of the electrophoretically more cathodal isoenzymes, of both LD and CK, progressively increase in this tissue, until approximately the sixth month of intrauterine life, when the pattern resembles that of differentiated muscle. Smaller quantitative changes in isoenzyme distribution may continue to birth and into early postnatal life. 

Knockout mice and Drosophila mutants have been used to explore the roles of MRF and MEF proteins in conferring myogenic specificity in intact animals, extending the work in cell culture. These experiments demonstrated the importance of three of the MRF proteins and of MEF proteins for distinct steps in muscle development (see Figure 22-14). The function of the fourth myogenic protein, Mrf4, is not entirely clear It may be expressed later and help maintain differentiated muscle cells and by combinatorial control to ensure that only muscle-specific genes are activated. 

It has been shown that actinomycin D, which stops DNA-dependent RNA synthesis, prevents the induction of mesodermal tissues in gastrula ectoderm when applied at a concentration of 1 / g/ml (Toivonen et at, 1964). When the upper blastoporal lip of Triturus gastrulae, which is already determined to differentiate muscle and notochord, together with the ectoderm induced by the blastoporal lip to form neural organs was explanted and treated with actinomycin D (0.5-2.5 / g/ml), a differential sensitivity of the organ anlagen was observed (Tiedemann et... 

Rong, R M., Ziller, C., Pena-Melian, A., and Le Douarin, N. M. (1987) A monoclonal antibody specific for avian early myogenic cells and differentiated muscle. Dev. Biol. 122, 338-353. 

Kinmer, C. R. and Brockes, J. (1984) Monoclonal antibodies identify blastemal cells derived from differentiating muscle in newt limb regeneration. Nature (London) 308,67-69. 

Fig. 11. DNA strand-breaks in differentiating muscle cells. 20 h culture labelled with ( C] thymidine 30, 42, 56 or 90 h cultures labelled with [ H] thymidine. Q ( H) [ CJ. Analysis was by the alkaline unwinding technique...

The physician should then passively put the upper extremity through the ranges of motion. This assists in differentiating muscle from joint pain or restriction. Passive motion relieves the muscle of work so that if they are the source of... 

Alterations of DNA replication with bromodeoxyuridine (which randomly replaces thymidine with bromouracil) inhibits biochemical differentiation. For instance, the increase of creatine phosphokinase activity is reduced in differentiating muscles (Holtzer, 1970). 

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