Horn sheath

The subunit eomposition is such that the intraeellular release of the viral genome horn its coat involves only the dissociahon of non-eovalently bonded subunits, rather than the degradation of an integral protein sheath. 

Rhinoceros horns are composed of densely compressed hair-like fibers over a stubby bone core that is part of the skull. They are composed of a dense growth of epidermal cells and dermal papillae, which are similar to thick hair. These are not really true hairs, since they do not grow from a follicle in the skin. Unlike the sheath-like horns of cattle and buffalo, rhino horns are mosdy solid. 

Horn fi om the rhino is different firom other types of hom, as it is composed entirely of compacted strands of keratin, so that it is solid with no bony core. Other types of hom are thin sheaths of homy material covering a bony core. Rhinos horns grow throughout the animals lives, and can regrow if broken or damaged. They grow om the skin on the animals noses (Fig. 6.1). 

Rams horn is more compact than other types of horn, so it is harder to woi but gives very beautiful results, llie sheath varies in thickness around its circumference, and is almost triangular in cross-secdon. It is also curved and ridged (Fig. 7.3). 

The lesions comprise degeneration of the myelin sheath of the nerves and nerve roots, with degeneration of the corresponding anterior horn cells and muscle fibers. The pathogenesis is unclear. Impairment of glutathione reductase has been considered. Even in healthy people, nitrofurantoin 400 mg/day for 2 weeks causes a significant increase in motor nerve conduction time. If strict attention is paid to the contraindication of renal insufficiency, the risk of polyneuropathy can be reduced. Careful controls for the initial symptoms of paresthesia can prevent the development of severe disablement. 

About 25 different human genes encode the keratins of skin and other soft tissues. Others specify the keratins of hair and nails.Both of these hard tissues as well as claws, hoofs, beaks, horns, scales, quills, and feathers are largely keratin. However, there are additional constituents. During the final stages of keratinocyte differentiation a 15-nm-thick crosslinked sheath of protein, the cornified cell envelope (CE), forms beneath the plasma membrane. Crosslinkages between keratin and other proteins are formed by the action of transglutaminases. " ... 

Figure 6.11 Horning-crown macrocycle (derived from isoaromatization of 25) inclusion complexes with oc-methylphenethylamine and propylenedia-mine contain ball-like structures (left) and sheath/core structures (right), respectively.

In cattle, sheep. Old World antelopes and related animals, the horns are permanent, unhranched and are usually present in hoth sexes. They are composed of a sheath of keratin (a tough fibrous material derived from epithelial tissue) overlying a bony core projecting from the skull. In pigment terms the references to horn do not actually refer to horn, but to the antlers of deer (stags or hinds) which are not strictly horns Columbia Encydopedia, 2003)... 

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