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C A Shuttleworth

Publications and source records attributed to C A Shuttleworth.

85 records · Page 5Linked to original sources

Changes in guinea-pig dermal collagen during development.

Guinea-pig dermis was digested with pepsin and the solubilized collagen molecules separated by differential salt precipitation at pH 7.5. Differences in subunit composition and amino acid analysis were noted between type I and type III collagen. Incorporation of radioactive proline into the developing foetus enabled isolation of labelled type I and type III collagens. Comparison of the specific activity of the isolated collagen molecules showed that type III collagen had a high specific activity in the early stages of foetal development, which decreased dramatically during foetal development. The specific activity of pepsin-solubilized type I collagen remained fairly constant during foetal development.

Amino Acids↗

Comparison of the cyanogen bromide peptides of insoluble guinea-pig skin and scar collagen.

Insoluble guinea-pig skin collagen and insoluble dermal scar collagen were cleaved with CNBr and the peptides derived from the alpha1-chain were separated by ion-exchange and molecular-sieve chromatography. Comparison of the peptides from scar collagen with those from skin collagen showed that the former contained more hydroxylysine. Separation of the CNBr peptides showed that this increase in hydroxylysine was found not only in the non-helical regions, but was also seen down the helical portion of the molecule. Separation of the peptides revealed the presence of more peptides in digests of skin collagen than those of scar, and these have been attributed to the presence of Type III collagen in skin, but no evidence was found for the presence of this Type III collagen in dermal scar tissue.

Amino Acids↗

Scanning transmission electron microscopy mass analysis of fibrillin-containing microfibrils from foetal elastic tissues.

We have applied scanning transmission electron microscopy to intact native fibrillin-containing microfibrils isolated from foetal bovine elastic tissues in order to derive new insights into microfibril organisation. This technique provides quantitative data on the mass per unit length and axial mass distribution of unstained, unshadowed macromolecules. Scanning transmission electron microscopy of microfibrils from aorta, skin and nuchal ligament revealed that the beads corresponded to peaks of mass and the interbead regions to troughs of mass. These major features of axial mass distribution were characteristic of all microfibrils examined. Tissue-specific and age-dependent variations in mass were identified in microfibrils that were structurally comparable by rotary shadowing electron microscopy. Increased microfibril mass correlated with increasing gestational age. The additional mass was associated predominantly at, or close to, the bead. Some microfibril populations exhibited pronounced assymetry in their axial mass distribution. These data indicate that intact native microfibrillar assemblies from developing elastic tissues are heterogeneous in composition. Loss of mass following chondroitinase ABC or AC lyase treatment confirmed the presence of chondroitin sulphate in nuchal ligament microfibrillar assemblies.

Actin Cytoskeleton↗