Biomedical subjects

I Buggia

Publications and source records attributed to I Buggia.

4 recordsLinked to original sources

PubMed1994

High-performance liquid chromatography determination of pravastatin in plasma.

Pravastatin is a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor that reduces plasma cholesterol levels. Some analytical methods have been described for determination of pravastatin levels in biological fluids, but these methods are rather cumbersome and involve expensive specialized equipment, usually not available in a clinical setting. A new technique, reversed-phase high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection capability, has been developed for the analytical determination of pravastatin in plasma. Extraction and sample clean-up procedures are simple and rapid to execute, yet yield chromatograms virtually free of interference from endogenous plasma constituents and other antihypercholesterolemic agents or drugs usually taken concomitantly with pravastatin. Our detection limit for pravastatin was 2 ng/ml. Standard curves were linear between 5 and 200 ng/ml, with a coefficient of variation (CV) of < 10% at the limits of quantitation. This method was used to study pravastatin plasma levels in two hypercholesterolemic heart-transplant recipients and two hypercholesterolemic nontransplanted patients. We conclude that the method reported here would be ideal for therapeutic pravastatin monitoring in patients.

Chromatography, High Pressure Liquid↗

PubMed1994

Evaluation of two buflomedil tablet formulations in patients with atherosclerotic disease.

The bioequivalence of a 600-mg methocel tablet containing buflomedil hydrochloride in sustained-release form was determined relative to a 300-mg CAP/carbovax-coated tablet of buflomedil hydrochloride in immediate-release form. The tablets were given to 20 patients in a double-blind placebo-controlled clinical study with cross-over between the administration plans. The 300-mg tablets were given b.i.d., at 8 a.m. and 8 p.m. while the 600-mg tablets were taken once a day at 8 a.m. (+placebo at 8 p.m.). Plasma samples were collected at appropriate times up to 24 h after administration and were analyzed for buflomedil with a validated high-performance liquid chromatographic procedure. Results showed an overall significant mean difference in absorption rate between the two formulations. The mean tmax (5.5 +/- 3.5 h) for the 600-mg tablet was longer (P < 0.001) than the tmax value (1.8 +/- 0.8 h) seen after administration of the first 300-mg tablet. Analysis of AUC(O-infinity) values indicated that the sustained-release preparation (32.1 +/- 20.7 micrograms/ml h) was not significantly different from the 300-mg tablet b.i.d. (28.7 +/- 16.0 micrograms/ml h). Furthermore, it was seen that single administration of a 600-mg sustained-release tablet of buflomedil hydrochloride delivered the same amount of total drug as a 300-mg tablet given twice a day.

Aged↗

PubMed1994

Busulfan.

OBJECTIVE: To review the current published studies evaluating the pharmacokinetics, clinical efficacy, safety, and toxicity of busulfan in pediatric and adult patients. DATA SOURCES: English-language literature published between 1953 and 1993 was analyzed; pertinent literature was reviewed. STUDY SELECTION: Emphasis was placed on pharmacologic studies and clinical trials involving busulfan therapy both in myeloproliferative disorders and in conditioning regimens for autologous or allogeneic bone marrow transplantation. DATA EXTRACTION: Data from both pediatric and adult studies were evaluated; emphasis was placed on the relationship between plasma concentrations of busulfan and its efficacy and toxicity. DATA SYNTHESIS: Busulfan has been used widely at conventional dosages (1-12 mg/d) for the treatment of patients with chronic myelogenous leukemia (CML). Busulfan at high doses (usually 16 mg/kg) given with other cytotoxic drugs (especially cyclophosphamide) is a common preparative regimen in patients undergoing allogeneic or autologous bone marrow transplantation (BMT) for acute or chronic leukemia and other nonmalignant disorders (e.g., hemoglobinopathies, inborn error of immune system, congenital metabolic disorders). Pharmacokinetics of high-dose busulfan are age-dependent. Busulfan systemic exposure and, thus, tissue and tumor exposure are lower in children than with adults. Relationships between toxicity (principally neutropenia, hepatic veno-occlusive disease, incidence of seizures) and drug exposure were found for busulfan. CONCLUSIONS: Busulfan is a useful, sufficiently safe drug in the treatment of patients with CML. At higher dosages, busulfan is a fundamental part of myeloablative therapies for patients undergoing BMT. As the pharmacokinetics and metabolism of busulfan is further understood, there is great potential for improving treatment outcome. An assessment of maximal tolerated exposure determined by therapeutic drug monitoring may decrease the incidence and lethality of regimen-related toxicities.

Age Factors↗

PubMed1992

[The bioavailability of nicorandil after oral administration of a single dose of 10 or 20 mg preparations].

To evaluate the bioavailability of 4 different formulations of nicorandil, 10 mg and 20 mg (Bracco) versus 10 mg ang 20 mg (Merck), we have carried out a study involving 24 young healthy volunteers. The drug was administered in single oral dose and the plasma concentration levels were evaluated by HPLC method. From the results obtained, we have seen that both the 2 products of 10 mg (A and B) and the 2 products of 20 mg (C and D) are equivalent and have high relative bioavailability: it reaches the values of 96.5% (A versus B) and 120% (C versus D). As regards the 2 formulation of 20 mg, the results of bioavailability are confirmed by data obtained from dissolution study in vitro, where the dissolution is almost complete in 30 minutes.

Adult↗