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Biomedical subjects

D D Perrin

Publications and source records attributed to D D Perrin.

At least 19 recordsLinked to original sources

Dissolution of urinary stones by calcium-chelating agents: A study using a model system.

Pellets made by dispersing microcrystals of calcium oxalate monohydrate throughout an organic matrix have served as models for kidney stones in studies of factors governing their dissolution by calcium-chelating agents. These factors include pH, ionic strength, concentration of chelating agent, and addition of other acids and bases. The method shows good reproducibility. Results have been applied to improving a clinical procedure for kidney stone dissolution.

Calcium↗

Computer-based approach to chelation therapy: a theoretical study of some chelating agents for the selective removal of toxic metal ions from plasma.

COMICS is a computer programme for calculating equilibrium concentrations of metal complexes and reactive species in multi-metal-multi-ligand systems. Its usefulness for analysing metal ion equilibria in blood plasma has been improved by including albumin as a ligand. Using this model system the distribution and removal of copper(II) and zinc ions in histidinaemia, lead poisoning and Wilson's disease have been examined. The efficacy of TRIEN in removing excess copper(II) is shown. The use of specific tripeptides such as Gly-Gly-His methyl ester for the selective removal of copper(II) is suggested. A possible chemoprophylaxis of influenza based on complexation of zinc is discussed. Calculations confirm that thiosemicarbazones such as methisazone and 2-acetylpyridine thiosemicarbazone are effective competitors for heavy metal ions under physiological conditions.

Amino Acid Metabolism, Inborn Errors↗

The computed distribution of copper(II) and zinc(II) ions among seventeen amino acids present in human blood plasma.

The equilibrium distribution of copper(II) and zinc(II) ions among a mixture of 17 amino acids has been computed from stability-constant and blood-plasma-composition data. At pH7.4, 98% of the copper(II) in the simulated plasma solution is co-ordinated to histidine and cystine, predominantly as the mixed-ligand complexes [Cu.His.Cystine](-) and [Cu.H.His.Cystine]. Approximately half of the zinc(II) is co-ordinated to cysteine and histidine, but appreciable complex-formation occurs with most of the other amino acids. Stability constants are given for copper(II) and zinc(II) amino acid complexes, including some mixed-ligand species, at 37 degrees C and I=0.15m.

Amino Acids↗