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A Cockburn

Publications and source records attributed to A Cockburn.

35 records · Page 2Linked to original sources

Safety of ticarcillin disodium/potassium clavulanate.

Clavulanate potentiated ticarcillin contains two components with an established safety record. Ticarcillin used clinically alone and with clavulanate, a component of clavulanate potentiated amoxycillin, given orally or intravenously. No pharmacokinetic interaction occurs between the two components when given together in man or animals in which metabolism is qualitatively similar to man. Safety evaluation studies carried out in the animals established as suitable for studying the toxicology of ticarcillin have shown no unexpected synergistic or antagonistic toxic effects of Timentin not predicted from the toxicological evaluation of clavulanate alone. Reproductive mutagenic, cardiovascular and general pharmacological studies have shown no significant hazard from Timentin. Clinical experience with ticarcillin has been reviewed, and impairment of platelet function, seen at supratherapeutic doses, has been shown in an animal model not to be influenced by clavulanate. The assessment of the safety of ticarcillin and clavulanate for therapeutic use in man is thus comprised of the clinical experience with ticarcillin and parenteral clavulanate in clavulanate potentiated amoxycillin, animal safety evaluation studies, and the clinical experience with Timentin reported in this symposium.

Animals↗

Temocillin. Summary of safety studies.

Temocillin is a novel injectable beta-lactam antibiotic designed for parenteral use. It is active against the majority of Gram-negative bacteria and is stable to a wide range of beta-lactamases. Disposition and metabolic studies on temocillin in animals and man demonstrate that the drug is well distributed throughout the body tissues and will cross the placenta. The major route of elimination is via the kidney (89%) where the drug is excreted unchanged as parent compound, mainly by the glomerular filtration of unbound temocillin. A full toxicological safety evaluation programme has been completed and includes acute, subacute and chronic toxicology in rat and dog, and reproductive and mutagenicity studies. Temocillin was well tolerated in animals at dosages of up to 1000 mg/kg and appears to be without any potential hazard for man in dosages which are well in excess of the proposed therapeutic dose.

Animals↗

Where did our infectious diseases come from? The evolution of infectious disease.

Infectious diseases have been evolving from the earliest days of life on earth. Major factors influencing their developments include the splitting of continents (continental drift), the radiation of early primates into present-day forms, migrations of man around the world, the ending of the Ice Age, the invention of agriculture, the domestication of animals, the increase in populations, and the urbanization of societies. The impact of such basic changes on infectious diseases is reviewed.

Agriculture↗

DNA-protein interactions of the rat liver non-histone chromosomal protein.

Native rat liver NHC protein-DNA interactions have been investigated by use of a nitrocellulose filter assay sensitive in detection of protein-DNA complexes. Optimal conditions for DNA-protein interactions occurs at low ionic strength conditions (110 mM phosphate buffer). A fraction of NHC proteins was enriched 25-fold by their affinity for rat DNA immobilized on cellulose columns under these conditions. At higher ionic strength (260 mM-0.04M phosphate buffer and 0.15 M sodium chloride), this fraction binds approximately sevenfold less to rat DNA but with a substantial increase in stability of the complexes. Equilibrium competition experiments indicate that at the higher ionic strength there is a considerable DNA sequence specificity of the rat DNA binding NHC protein. Since rat DNA contains three components as defined by their reassociation kinetics: single copy DNA (C0t1/2pure = 1.6 times 103); middle repetitive DNA (C0t1?1PURE = 1.1); and highly repetitive (C0t1/2pure smaller than 0.02). The two former were isolated and employed in the DNA binding assays. At the high ionic strength criterion, the rat DNA binding NHC proteins showed a substantial preference for a subset of middle repetitive DNA sequences. This suggests a preferential interaction between a class of NHC proteins and a class of middle repetitive DNA sequences.

Animals↗