Effect of diclofenac on ocular levels of ciprofloxacin and lomefloxacin in rabbits with endophthalmitis.

The purpose of this study was to analyze ciprofloxacin and lomefloxacin penetration into the anterior eye tissues after topical instillation in healthy rabbits and with experimental Staphylococcus aureus endophthalmitis. Additionally, effect of diclofenac sodium eye drops on the distribution of both fluoroquinolones in the inflamed eye tissues was investigated. An intense protocol with frequent antibiotic administration was chosen.

A simulation model for the prediction of tissue:plasma partition coefficients for drug residues in natural casings.

Tissue residues arise from the exposure of animals to undesirable substances in animal feed materials and drinking water and to the therapeutic or zootechnical use of veterinary medicinal products. In the framework of this study, an advanced toxicokinetic model was developed to predict the likelihood of residue disposition of licensed veterinary products in natural casings used as envelope for a variety of meat products, such as sausages. The model proved suitable for the calculation of drug concentrations in the muscles of pigs, cattle and sheep, the major species of which intestines are used.

Functional studies on the activity of efflux transporters in an ex vivo model with chicken splenocytes and evaluation of selected fluoroquinolones in this model.

The efflux proteins P-glycoprotein (P-gp), BCRP and members of the MRP-family (MRPs) are increasingly recognized as determinants of the absorption, tissue distribution and excretion of numerous drugs. A widely applied in vitro screening method, to assess the effect of these efflux transporters in transmembrane transport of drugs is based on the use of peripheral blood mononuclear cells (PBMC), in which the efflux of fluorescent dye Rhodamine 123 (Rh-123) can be easily measured. In avian species, the isolation of PBMCs is compromised by the presence of thrombocytes having approximately the same size.

Integration of pharmacokinetic and pharmacodynamic indices of marbofloxacin in turkeys.

Fluoroquinolones are extensively used in the treatment of systemic bacterial infections in poultry, including systemic Escherichia coli bacillosis, which is a common disease in turkey flocks. Marbofloxacin has been licensed for use in various mammalian species, but not as yet for turkeys, although its kinetic properties distinguish it from other fluoroquinolones. For example, the longer half-life of marbofloxacin in many animal species has been appreciated in veterinary practice.