PubMed Health⌕ Search

Biomedical subjects

A Marzo

Publications and source records attributed to A Marzo.

158 records · Page 9Linked to original sources
PubMedDate not supplied

Mefenamic acid bioequivalence assessment with a new statistical procedure.

The bioequivalence of three different formulations of mefenamic acid was tested using the index zeta 2 previously defined by Rescigno. This index is a measure of the distance in Hilbert space of two concentration vs time functions; unlike the approach of Westlake which assumes a multiplicative model for the AUC and Cmax characteristics, this approach does not imply any hypotheses on the structure of the data and no particular model of the absorption or of the elimination processes. The index zeta 2 is simply an indication of how similar two formulations are. Results for this new test were compared with those obtained with two other tests, namely 90 and 95% symmetrical confidence intervals of Westlake and two one-sided t-tests of Shuirmann through the 90% confidence intervals in the ranges 80-125% for AUC and 70-143% for Cmax. Results of the new test are fully comparable with those obtained using the other two tests.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMedDate not supplied

Some pharmacokinetic considerations about homeostatic equilibrium of endogenous substances.

Endogenous substances in the body are controlled through simple, very effective mechanisms, that preserve an optimum homeostatic equilibrium of baseline concentration and restore it when impaired. When planning a pharmacokinetic investigation of an endogenous substance exogenously administered, it is imperative to carefully ascertain the above mechanisms as well as the baseline value and their possible variations associated with daily rhythm, food, age, sex, menstrual cycle. Often the control mechanisms operate through non-linear processes, therefore a non-compartmental analysis or a tailored model may be more appropriate than the compartmental models used in standard pharmacokinetic analysis. Some specific examples of endogenous substances are discussed here on the basis of the data from the literature and personal experience.

Bile Acids and Salts↗
PubMedDate not supplied

Pharmacokinetics of endogenous substances: some problems and some solutions.

The paper deals with the most relevant aspects related to the pharmacokinetics of endogenous substances. Two different views are presented in order to focus on two aspects of the problem, the physiological background of these substances and the need for empirical or tailored models to process pharmacokinetic data. Very often endogenous substances follow saturable enzyme biotransformation, reversible interconversion, active and diffusional transports, renal threshold, endogenous synthesis plus dietary supply with possible balancement between these two factors, feedback processes, asymmetric distribution with specific body storage, and gender differences. These mechanisms allow the body to preserve and restore homeostatic equilibria of endogenous substances. The most relevant problem in pharmacokinetics of these substances is the presence of baseline concentration which needs to be carefully defined also for possible rhythms related to age, sex, diet, night and day periods. Theoretical considerations are presented for the management of pharmacokinetic analysis of these substances, which only rarely follow linear processes. Throughout the text various practical examples are considered.

Animals↗
PubMedDate not supplied

Endoscopic evaluation of the effects of indobufen and aspirin in healthy volunteers.

This is an outcomes pharmacodynamic study using Nonsteroidal antiinflammatory agents, particularly acetylsalicylic acid (ASA), have been shown useful in various cardiovascular disorders, but they can be a major cause of iatrogenic gastrointestinal injury. Newer NSAIDs such as indobufen, an inhibitor of platelet aggregation that acts by reversibly inhibiting the platelet cyclooxygenase enzyme, have proven to be as effective as the older NSAIDs and appear to have a better gastrointestinal tolerability profile. When the gastroduodenal tolerability of 10 days of oral treatment with indobufen or ASA was assessed in healthy adult volunteers using endoscopic evaluation and the modified score scale of Lanza, only 1 of 18 (6%) volunteers who received indobufen had an increased erosion score at the completion of therapy, compared with 6 of 18 volunteers who received ASA (33%). Overall, both drugs were well tolerated. These results suggest that indobufen has a lower incidence of gastrointestinal effects than other NSAIDs and should be useful in the management of patients with cardiovascular disease.

Adolescent↗