Ana Rosa Abadía

Pharmacokinetics of ciprofloxacin in sheep after single intravenous or intramuscular administration

The disposition and urinary excretion of ciprofloxacin (CIP) following intravenous (IV) or intramuscular (IM) administration of 7.5 mg/kg body weight in sheep (n = 5) was studied. The intravenous plasma concentration curve was best described pharmacokinetically by a two-compartment open model, while the intramuscular administration data fitted better to a one-compartment open model. Mean elimination half-lives after IV and IM administration were 72 and 184 minutes, respectively. The absorption of intramuscularly administered CIP in sheep was fast: maximal plasma concentration (Cmax) was reached quickly (tmax 31.93 min) and attained values of 0.69 +/- 0.27 mg/l. The bioavailability was 49%. The urinary data showed a significant decrease in the elimination rate constant of CIP when CIP was administered intramuscularly. The other parameters calculated did not display differences between the two routes of administration. The results obtained suggest that when CIP was administered by the IM route in the assayed dose, it was able to maintain serum concentrations above the MIC of most common pathogens over an 8-hour period.

Limited capacity of neonatal rabbits to eliminate enrofloxacin and ciprofloxacin

The pharmacokinetics of enrofloxacin (ENR) and ciprofloxacin (CIP) in newborn and young rabbits were studied. Rabbits of different ages (1-, 8-, 16-, and 30-day-old) were administered, by the intraperitoneal route (i.p.), a dose of 7.5 mg of either drug/kg. In 1-, 8-, and 16-day-old rabbits, blood samples were drawn by cardiac puncture, under light ether anaesthesia, at predetermined times after drug administration. In 30-day-old rabbits, serial blood samples were drawn through an arterial catheter. Plasma was immediately obtained and analysed using an HPLC method. ENR and CIP plasma protein binding was also determined. The plasma pharmacokinetic profiles of ENR and CIP obtained for 30-day-old rabbits agreed with those reported in the literature for healthy adult rabbits. Nevertheless, significant differences were observed for the body clearance, the slope of the terminal phase, the volume of distribution, and the area under the curve when compared with those for younger animals (1-, 8-, and 16-day-old rabbits), indicating a limited capacity of neonatal rabbits to eliminate ENR and CIP. No differences were found when we compared the calculated values for ENR or CIP plasma protein binding as a function of the postnatal age, indicating that development does not seem to alter the free fraction of these drugs in the rabbit. Taking into account that extensive placental and milk transfer has been reported for these drugs after administration to pregnant or nursing rabbits, a cautious, attitude regarding their use in these animals must be adopted.

Deacetylation of Diltiazem by Several Rabbit Tissues

AbstractPurpose. Diltiazem (DTZ) undergoes extensive metabolism yielding several metabolites, some of which retain a certain degree of pharmacological activity. N-demethylating activity has been detected mainly in the liver. Nevertheless, the organs involved in the formation of the deacetylated metabolite of DTZ (Ml) have not been fully elucidated. In order to address this issue, we have carried out in vitro studies using the blood, lung, brain, small intestine, and liver as enzyme sources. Methods. DTZ (1,000 ng/ml) was incubated in 10,000 × g supernatant homogenates of selected tissues or in whole blood for 240 minutes at 37°C. Multiple samples were withdrawn, and DTZ and its metabolite Ml were assayed by HPLC. Results. The apparent degradation rate constant of DTZ was in the rank order blood > lung > brain > liver > small intestine. This trend can also be observed for the AUC and for the percentage of DTZ metabolized. In all the tissue homogenates examined there was a net production of the deacetylated metabolite. The Ml metabolite was also detected in the blood (500 ng/ml after 240 minutes of incubation). Conclusions. The widespread distribution of the DTZ deacetylase activity described in this study suggests that extrahepatic metabolism of DTZ to Ml may play a relevant role in the overall pharmacokinetics of DTZ.

Magnetic study of iron sorbitol

A magnetic study of iron sorbitol, an iron-containing drug to treat the iron deficiency anemia is presented. Transmission electron microscopy reveals that the system contains nanometric particles with an average diameter of 3 nm whose composition is close to two-line ferrihydrite. The characterisation by magnetisation and AC susceptibility measurements indicates superparamagnetic behaviour with progressive magnetic blocking starting at 8 K. The quantitative analysis of the magnetic results indicates that the system consists of an assembly of very small magnetic moments, presumably originated by spin uncompensation of the antiferromagnetic nanoparticles, with Arrhenius type magnetic dynamics.

Mirada a los clásicos. "Cine forum", nuevo enfoque interdisciplinar en el Grado de Óptica y Optometría - [A look back at the classics."Cinema forum", new interdisciplinary approach in the Optics and Optometry Degree]

Five academic years ago, an interdisciplinary collaboration started between two subjects belonging to different areas of knowledge in the first year of the Optics and Optometry Degree at the University of Zaragoza. This collaboration focuses on Problem-Based Learning (PbL) and Portfolios methodologies. With the purpose of exploring new educational strategies that allow us to approach both subjects comprehensively, and without abandoning those that we already have integrated in the teaching of our subjects, we have used, during the present academic year 2016-17, the cinema as a formative resource; obtaining clearly satisfactory results since the students, besides working purely technical aspects of the subjects, appreciated learning in terms of more emotional, affective or empathic aspects as future health professionals.

Valoración de la utilización de SOCRATIVE como herramienta didáctica interactiva en dos asignaturas del grado en Óptica-Optometría de la Universidad de Zaragoza

Se presenta el analisis de la herramienta digital docente SOCRATIVE en relacion a diversas modalidades y finalidades de utilizacion. La experiencia se ha realizado en el marco del trabajo interdisciplinar desarrollado en las asignaturas: “Anatomia e Histologia Ocular” y “Fisiologia Ocular y del Sistema Visual” del primer curso del Grado en Optica y Optometria de la Universidad de Zaragoza. Se ha utilizado SOCRATIVE para que en clase los estudiantes, por grupos, respondiesen a un cuestionario, en un caso con retroalimentacion inmediata, en otro con un caracter mas evaluativo y por ultimo como herramienta de Tutoria de grupo completo. Una de las ventajas de esta practica es la rapidez en la obtencion de informacion acerca del grado de comprension de la asignatura por los estudiantes, asi como en la retroalimentacion ofrecida. Para su utilizacion como herramienta de evaluacion se constata la necesidad de acotar adecuadamente las condiciones de la misma. En cuanto a la opinion de los estudiantes, lo consideran bastante o muy util como herramienta de aprendizaje, pero no asi para la evaluacion.