Muscle human, composition

It is obvious that one should not expect to find in the literature extensive information regarding the composition of the brains, livers, or even muscles of healthy human individualsespecially so since repeated samples would have to be taken for analysis in order to determine conclusively the importance of inter-individual differences. The best that could be hoped for would be extensive "horizontal" studies relative to the composition of blood, secretions, etc., of individual human specimens and, perhaps, more comprehensive data including tissue composition with respect to animals. However, satisfactory studies of this sort have seldom, if ever, been made. More often than not, such horizontal studies as have been made have not been published in complete enough form to give the kind of information needed to answer the questions which we are considering. 

Ferritin is composed by the arrangement of 24 protein subunits, which results in a hollow shell of 8 nm inner diameter and 13 nm outer diameter (Fig. 13). Ferritin from vertebrates have two types of subunits heavy (H) and light (L). The subunit composition of human ferritins depends on the origin of the protein H2L22 for liver ferritin, H20L4 for muscle ferritin, etc. Access channels are formed by the intersection of subunits. The 8 channels located at the intersection of three subunits are hydrophilic while the 6 channels located at the intersection of 4 subunits are hydrophobic. The empty protein is called apoferritin (30). 

Chemical substances, which are injected into laboratory animals, may cause tumors locally at the injection site, e.g., in the muscle, irrespective of the mechanism for the tumor formation. It is now well established that smooth-surfaced foreign bodies, regardless of their chemical composition, will produce sarcomas when transplanted subcutaneously into rodents (Moore 1991). It is difficult to evaluate the relevance for humans of such site-related tumor formation this issue has been further addressed by lARC (1999b). 

A minor measure of civilization s progress is that television androids now look more realistic their limbs flex like a human s. Artificial joints and muscles are becoming more realistic as new lightweight soft technologies replace the steels of the industrial age and even the plastics of the twentieth century. Some new materials flex when an electrical impulse is passed through, and others expand more than 100 times when the temperature is raised by 1°C. The nonmetals and metalloids play an important role in these new materials, especially in gels, composite materials, ceramics, polymers, artificial muscle, and luminescent materials. 

Maclellan, D.L., Steen, H., Adam, R.M., Garlick, M., Zurakowski, D., Gygi, S.P., Freeman, M.R. and Solomon, K.R. (2005) A quantitative proteomic analysis of growth factor-induced compositional changes in lipid rafts of human smooth muscle cells. Proteomics 5, 4733-4742, Published on-line. 

The amino acid compositions of two phosphorylases have been determined, and are shown in Table XVI. The complete, amino acid sequence or three-dimensional structure of a phosphorylase is not yet known, and the task of delineating it will be difficult because of the large size of the molecules. However, the sequence of amino acids about an important phosphoserine residue has been reported for rabbit and human muscle phosphorylase a. In the rabbit enzyme, the sequence is... 

Amino Acid Composition" of Phosphorylase b of Babbit Muscle and Human Muscle... 

Bodor GS, Survant L, Voss EM, Smith S, Porterfield D, Apple FS. Cardiac troponin T composition in normal and regenerating human skeletal muscle. Clin Chem 1997 43 476-84. 

The fatty acid composition of muscle lipids may show quantitative alterations in diseased muscle. Thus lecithin isolated from human dystrophic muscle had an increased amount of oleic but diminished linoleic acid (Tl). Changes have been recorded also in the fatty acid composition of lecithin from denervated muscle (PI). Recently it has been reported (K16) that the fatty acid pattern of muscle phosphatides from patients with the autosomal dominant form of myotonia congenita differed markedly from that of the autosomal recessive form and from the normal. Tani and his co-workers (F7) have made a detailed study of the phospholipids of normal and dystrophic mouse tissues. In normal mice phosphatidylcholine and phosphatidylethanolamine from skeletal and heart muscles had a very high content of 20-22-carbon polyunsaturated acids, in comparison with those for other tissues the most abundant was docosahexaenoic acid. In dystrophic mice there was a sharp decrease in the proportion of docosahexaenoic acid in the phosphoglycerides from skeletal and heart muscles, suggesting the likelihood of important alterations in muscle membranes. Somewhat similar studies have been reported by Owens (05), who also observed a fall in the proportion of docosahexaenoic acid, mainly in the phosphatidylcholine -j- choline plasmalogen fraction. 

Tl. Takagi, A., Muto, Y., Takahashi, Y., and Nakao, K., Fatty acid composition of lecithin from muscles in human progressive muscular dystrophy. Clin. Chim. Acta 20, 41-42 (1968). 

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