PubMed Health⌕ Search

Biomedical subjects

J GROSS

Publications and source records attributed to J GROSS.

At least 19 recordsLinked to original sources
PubMed1964

THERMAL DENATURATION OF COLLAGEN IN THE DISPERSED AND SOLID STATE.

Thermal denaturation temperature of newly reconstituted collagen fibrils from rat tail tendons is 52 degrees C compared with 42 degrees C for neutral solutions. This suggests that the increase in concentration of collagen within the fibril increases the stability of the individual molecules. The absence of firm intermolecular bonds in these fibrils rules out crosslinking as an explanation for increased stability. "Aging" at 37 degrees C up to 1 year raises the shrinkage temperature of reconstituted fibrous gels by 4 degrees to 6 degrees C and greatly increases resistance to dissolution at high temperature. The newly formed fibrils dissolve without shrinking, whereas older gels exhibit shrinkage before dissolution. Since nearly all extractable collagen is in the form of fibrillar aggregates in tissue, it is unlikely that thermal denaturation occurs at body temperature; therefore it could not be involved as a necessary stage in collagen resorption.

Aging↗
PubMed1964

COLLAGEN METABOLISM IN THE NORMAL AND LATHYRITIC CHICK.

1. Radioisotope incorporation studies of normal and lathyritic chick embryo bone collagen do not demonstrate any interference by lathyrism with collagen synthesis or fibril formation. 2. The results indicate that a portion of the extractable collagen from lathyritic chick embryo bone represents newly synthesized protein. Evidence from a double labeling experiment and from analysis of isotope flow between the extractable and non-extractable pools suggests the extractable lathyritic collagen is heterogeneous. We propose that the lathyritic process affects collagen in all states of aggregation, probably in varying degree. 3. Puromycin, administered intravenously, reduces the amount of extractable collagen in both normal and lathyritic chick embryo bone, and diminishes the incorporation of labeled proline into collagen. 4. Marked fluctuations in incorporation of labeled amino acids into chick embryo bone collagen suggests the occurrence of wide fluctuations in metabolism of this protein.

Amino Acids↗
PubMed1964

ORGANIZATION AND DISORGANIZATION OF COLLAGEN.

The organization of the normal collagen molecule and fibrils is reviewed and the detection, assay, and isolation of a collagenolytic enzyme from amphibian tadpole tissue are described and its possible significance in metamorphosis is discussed

Animals↗