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Biomedical subjects

G Carpenter

Publications and source records attributed to G Carpenter.

194 records · Page 11Linked to original sources
PubMed1975

Characterization of the binding of 125-I-labeled epidermal growth factor to human fibroblasts.

Epidermal growth factor (EGF) was labeled with 125-I by a lactoperoxidase technique. The unlabeled, monoiodinated and diiodinated species were separated by DEAE-cellulose chromatography and found to possess equivalent biological activities. The binding of monoiodinated epidermal growth factor to human fibroblasts was specific in that unrelated polypeptides did not affect the binding reaction. The binding reaction was a saturable process and was time- and temperature-dependent. A Scatchard analysis of the binding data indicated that each cell was capable of binding approximately 100, 000 molecules of 125-I-EGF. The apparent dissociation constant for the binding reaction was calculated to be 2.7 to 4.3 times 10-minus 10 M. Subsequent to the binding of 125-I-EGF to the fibroblasts, the growth factor was degraded by a cell-mediated proteolysis and [125-I]monoiodotyrosine appeared in the medium. The extent of degradation was reduced by the protease inhibitors, tosyl-L-lysine chloromethyl ketone and the benzyl ester of guanidobenzoic acid. Active binding sites of 125-I-egf appeared to be present in some but not all cell types. These results demonstrated that cells derived from a number of species (human, mouse, rat, and chick) possessed receptors that interacted with this mouse-derived growth factor.

Animals↗
PubMed1975

Human epidermal growth factor: isolation and chemical and biological properties.

A polypeptide hormone has been isolated from human urine, human epidermal growth factor. It was assayed by its ability to compete with 125I-labeled mouse-derived epidermal growth factor in binding to human foreskin fibroblasts. The biological effects of the human polypeptide are similar to those previously described for the mouse hormone. These include the stimulation of the growth in vitro of human foreskin fibroblasts and corneal epithelial cells in organ culture, and the in vivo induction of precocious eyelid opening in the newborn mouse. The amino acid compositions of the two polypeptides differ, although certain similarities are present. The estimated molecular weight of the human polypeptide, 5300-5500, is slightly lower than that of the mouse hormone. Both polypeptides apparently compete for the same site on the cell membrane; and antibodies to the mouse polypeptide crossreact to some extent with the human hormone.

Amino Acids↗
PubMedDate not supplied

Gray scale ultrasound studies in neonatal infants with malformation of the brain.

Ultrasound findings in four newborn infants with neurological abnormalities and abnormal facies are described. The ultrasound images are compared with the images achieved by computerized tomography and with the findings at postmortem in 3 of the patients. Accurate neuroanatomical diagnosis confirmed by CT and/or autopsy findings is demonstrated in all 4 cases. It is concluded that ultrasound, particularly using an automated water path scanner, is a viable alternative in the investigation of brain malformation in the neonate.

Brain↗