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Biomedical subjects

G Fitzgerald

Publications and source records attributed to G Fitzgerald.

28 records · Page 2Linked to original sources
PubMed1983

The physical effects of visco elastic substances on human donor cornea.

A case of corneal graft operation using chondroitin sulphate (CDS-TM) to protect the endothelium, highlights the surgical difficulties encountered as a result of the severe dehydration effects on the donor corneal button produced by the CDS. In vitro experiments comparing Healonid and CDS on 8 mm excised donor corneal buttons from three pairs of human eyes, confirms this effect with CDS which was absent with Healonid.

Adult↗
PubMed1981

Inhibition of reverse transcriptase by tyrosinase generated quinones related to levodopa and dopamine.

Several derivatives of levodopa have been shown to be potent inhibitors of the sulfhydryl enzyme, RNA dependent DNA polymerase, reverse transcriptase (RT). In the presence of the polyphenol oxidase, tyrosinase, the inhibitory values were between 10(-6) M and 10(-5) M. Structure-activity studies revealed that active oxidation or reduction was necessary for this potent inhibitory response. Spectrophotometric analysis showed that the presence of both the quinone and quinol was required for maximum inhibitory activity. These data suggest that the common intermediate of oxidation of quinols or reduction of quinones (i.e., semiquinone) is the active species. The use of tyrosinase provides a convenient model for the detection of the actual inhibitory interaction of a free-radical (semiquinone) with a biologically important macromolecule, reverse transcriptase.

Avian Myeloblastosis Virus↗
PubMed1978

Effect of peroral administration of xylitol on exocrine secretions of monkeys.

The effects of the administration of xylitol on the biochemical properties of monkey parotid and submandibular saliva and lacrimal fluid were investigated. Monkeys (Macaca mulatta) were fed either a sucrose or xylitol diet for 3 days. Ingestion of xylitol was associated with a significant increase of the activity of the salivary lactoperoxidase. The concentration of protein was also increased. Higher lactoperoxidase activity was found in parotid than in submandibular saliva. The concentrations of inorganic phosphate, calcium and SCN ions were practically unaffected. The concentration of SCN ions in pilocarpine stimulated monkey saliva was low (less than 5.5 mg/liter). Peroral administration of 2.5 g of xylitol or sorbitol per day to M. fascicularis resulted in almost similar levels of salivary lactoperoxidase activity. The administration of xylitol orally or by gastric intubation was not found to affect the concentration of lactoperoxidase, protein, phosphate, and SCN and iodine ions in lacrimal fluid. The results suggest that specific dietary sugars have a selective effect on the biochemical properties of saliva.

Animals↗