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G Cetta

Publications and source records attributed to G Cetta.

At least 91 records · Page 5Linked to original sources
PubMedDate not supplied

Transient beneficial effect of GH replacement therapy and topical GH application on skin ulcers in a boy with prolidase deficiency.

A diagnostic examination for short stature in a boy with chronic ulcers of the feet due to prolidase deficiency, a rare disorder associated with intractable ulcers of the skin, led to the diagnosis of growth hormone (GH) deficiency. Replacement treatment with r-hGH associated with the topical application of a GH-containing ointment when the boy was 13 years old resulted in complete but transitory healing of the ulcers, which can probably be attributed to the growth-promoting effects of GH on dermal connective tissue.

Adolescent↗
PubMedDate not supplied

Prolidase deficiency: biochemical study of erythrocyte and skin fibroblast prolidase activity in Italian patients.

BACKGROUND AND METHODS: Prolidase deficiency (PD), a rare, autosomally inherited disorder causing iminodipeptiduria is associated with a number of clinical manifestations, the principle feature being chronic skin ulceration. The enzyme prolidase cleaves iminodipeptides containing C-terminal prolyl or hydroxyprolyl residues and is important in the final stages of protein catabolism. We report clinical and biochemical findings in 8 Italian patients with proven prolidase deficiency. There was considerable heterogeneity in age at onset of symptoms (varying from 3-17 years), mental retardation and clinical manifestations (asymptomless to very severe). Prolidase activity was determined in hemolysates of patient erythrocytes and cultured dermal fibroblasts. RESULTS: Prolidase activity was found to be deficient, especially against gly-pro. Erythrocyte and fibroblast enzyme was also separated into two forms, a major isoform (I) and a minor one (II) by fast protein liquid chromatography, and activity against different iminodipeptide substrates was tested. Isoform I activity was markedly reduced in all patients as compared to normal controls, while isoform II activity appeared to be unaltered. CONCLUSIONS: We were unable to find any correlation between degree of enzyme activity loss and severity of symptoms.

Adolescent↗
PubMedDate not supplied

Effect of the triterpenoid fraction of Centella asiatica on macromolecules of the connective matrix in human skin fibroblast cultures.

The mechanism of action of the total triterpenoid fraction extracted from Centella Asiatica (TTFCA) was evaluated using human skin fibroblasts cultures as the experimental system. In particular its influence on the biosynthesis of collagen, fibronectin and proteoglycans was considered. The presence of TTFCA (25 micrograms/ml) does not seem to affect cell proliferation, total protein synthesis or the biosynthesis of proteoglycans in a significant way. A statistically important increase was observed in the percentage of collagen and, as revealed by immunofluorescence measurements, in cell layer fibronectin. This effect on collagen and fibronectin may help to explain the action of TTFCA in promoting wound healing, and suggests an interesting working hypothesis for its action on basal endothelia.

Cell Survival↗
PubMedDate not supplied

Localization of a structural defect in type I procollagen in a patient affected with the severe non-lethal form of Osteogenesis imperfecta.

A case of severe non-lethal Osteogenesis imperfecta was studied. The patient's cultured skin fibroblasts synthesised a mixed population of type I collagen chains some of which showed abnormal behaviour on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Further analysis revealed that two types of alpha 1(I) chains were synthesised, both an abnormal, slower migrating and a normal species. A small defect in one allele of one of the type I procollagen chains could lead to the larger size of the abnormal chains, probably caused by overmodifications of the triple helical region. CNBr peptide mapping allowed us to localise the defect midway along the triple helix: the defect site could be assigned to the region between the alpha 1(I)CB-3 and CB-7 peptides. The abnormal alpha 1(I) chains synthesised by the patient's cells had a melting temperature which was about 2 degrees C lower than normal chains. The results appear to be in agreement with the defect localisation and the phenotype.

Amino Acids↗