Search results for "pharmacodynamic"
showing 10 items of 85 documents
Semi-mechanistic Pharmacokinetic/Pharmacodynamic model of three pegylated rHuEPO and ior®EPOCIM in New Zealand rabbits.
2018
Abstract Marketed formulations of erythropoietin (EPO) ior®EPOCIM, MIRCERA® and two newly developed pegylated-EPO analogues (PEG-EPO 32 and 40 kDa) formulations were intravenously administered to New Zealand rabbits. A semi-mechanistic Pharmacokinetic/Pharmacodynamic (PK/PD) model describing in a simultaneous and integrated form the time course of reticulocytes, red blood cells and hemoglobin was built to account for the time course of hematopoiesis stimulation after erythropoietin administration. Data analysis was performed based on the population approach with the software NONMEM version 7.3. Erythropoietin disposition of each of the administered formulations was best described with a two…
Involvement of Dopamine D2 Receptors in Addictive-Like Behaviour for Acetaldehyde
2014
Acetaldehyde, the first metabolite of ethanol, is active in the central nervous system, where it exerts motivational properties. Acetaldehyde is able to induce drinking behaviour in operant-conflict paradigms that resemble the core features of the addictive phenotype: drug-intake acquisition and maintenance, drug-seeking, relapse and drug use despite negative consequences. Since acetaldehyde directly stimulates dopamine neuronal firing in the mesolimbic system, the aim of this study was the investigation of dopamine D2-receptors' role in the onset of the operant drinking behaviour for acetaldehyde in different functional stages, by the administration of two different D2-receptor agonists, q…
DALI: Defining Antibiotic Levels in Intensive Care Unit Patients: Are Current -Lactam Antibiotic Doses Sufficient for Critically Ill Patients?
2014
Background. Morbidity and mortality for critically ill patients with infections remains a global healthcare problem. We aimed to determine whether α-lactam antibiotic dosing in critically ill patients achieves concentrations associated with maximal activity and whether antibiotic concentrations affect patient outcome.Methods. This was a prospective, multinational pharmacokinetic point-prevalence study including 8 α-lactam antibiotics. Two blood samples were taken from each patient during a single dosing interval. The primary pharmacokinetic/pharmacodynamic targets were free antibiotic concentrations above the minimum inhibitory concentration (MIC) of the pathogen at both 50% (50% f TMIC) an…
Cetuximab administered once every second week to patients with metastatic colorectal cancer: a two-part pharmacokinetic/pharmacodynamic phase I dose-…
2009
Abstract Background This phase I dose-escalation study was designed to determine the maximum tolerated dose (MTD) and recommended dose of cetuximab administered on an every-second-week schedule to patients with metastatic colorectal cancer, on the basis of safety, pharmacokinetic and pharmacodynamic evaluation. Patients and methods The study comprised two parts: a 6-week cetuximab monotherapy dose-escalation phase and a subsequent combination therapy phase, during which patients received cetuximab, at the same dose/schedule as in the monotherapy phase, followed by irinotecan plus infusional 5-fluorouracil/folinic acid (FOLFIRI). Patients in the control group received cetuximab as a 400 mg/m…
Sirolimus exposure and the occurrence of cytomegalovirus DNAemia after allogeneic hematopoietic stem cell transplantation
2018
Sirolimus appears to protect against cytomegalovirus (CMV) in organ transplant recipients. The effect of this drug in allogeneic hematopoietic stem cell transplantation recipients remains unexplored. By means of multivariate continuous-time Markov model analyses, we identified 3 independent covariates that significantly impacted the risk of CMV DNAemia: recipient/donor CMV serostatus, tacrolimus exposure, and sirolimus exposure. CMV-seropositive recipients with CMV-seronegative donors had a significantly higher probability of having detectable CMV DNAemia. Increasing the tacrolimus trough concentration from 0 to 16 ng/mL increased the probability of patients having detectable CMV DNAemia by…
The Pharmacokinetics of Metronidazole and Gentamicin in a Single Preoperative Dose as Antibiotic Prophylaxis in Colorectal Surgery
2008
Objective: To describe, in patients undergoing colorectal surgery (CRS), the pharmacokinetics of a single, prophylactic preoperative dose of 1500 mg of metronidazole plus 240 mg gentamicin and measure its efficacy in accordance with the accepted pharmacodynamic and microbiological parameters. Method: Thirty-six patients undergoing CRS agreed to participate in the study. Three blood samples were taken from each. Cmax 15 minutes after finishing the infusion of the mixture, CfinIQ on finishing the surgery, and Cmin between 12 and 24 hours post-administration. The concentrations of metronidazole and gentamicin in each simple were measured and the pharmacokinetic parameters were estimated (dV-di…
Lack of effect of azithromycin on QT interval in children: a cohort study.
2016
Macrolides are a group of antimicrobial drugs used widely, being well known for their adverse cardiac effects. Erythromycin and clarithromycin are most commonly associated with these conditions. In recent years, azithromycin (AZM) has been assessed because of its possible relation to arrhythmias (mainly QT interval prolongation) and risk of cardiovascular death.1 The pharmacodynamics of these effects is complex and the occurrence of cardiovascular death is unpredictable.2 However, all published manuscripts on the cardiac effects of AZM to date are cases in adults or …
Action of the racemate and the isomers of the platelet-activating factor antagonist bepafant (WEB 2170) after oral administration to guinea-pigs and …
1991
The aim of the present study was to clarify whether there is a difference in terms of potency and pharmacodynamic half time between the isomers and the racemate of the platelet-activating factor antagonist WEB 2170 (bepafant) after oral administration to guineapigs or rats. The following experiments were performed in the guinea-pig. Infusion of platelet-activating factor at 30 ng/ (kg × min) for 30 min to anaesthetized guinea-pigs induced a decrease of respiratory flow and mean arterial blood pressure. Oral pretreatment with WEB 2170 or isomers, respectively, 60 min before infusion of plateletactivating factor inhibited these changes in a dose-dependent manner. The ED50S for inhibition of r…
Variability in individual response to various doses of omeprazole. Implications for antiulcer therapy.
1994
This study was carried out in order to perform a combined prospective assessment of the individual pharmacodynamic response and of duodenal ulcer healing in patients treated with three different doses of omeprazole. Ninety-nine patients with endoscopically proven duodenal ulcers were subdivided into three parallel groups of 33 cases, who were randomly assigned to receive orally at 0800 hr, in single blind fashion, either 10 mg, 20 mg, or 40 mg of omeprazole. All of them underwent continuous intragastric pH monitoring both in basal conditions and on the fifth day of each dose regimen; ulcer healing was then assessed endoscopically after four weeks of treatment. All three doses of omeprazole …
In vivo efficacy of humanised intermittent versus continuous ceftazidime in combination with tobramycin in an experimental model of pseudomonal pneum…
2008
In this study, we compared the efficacy of ceftazidime (CAZ) intermittent versus continuous infusion with or without tobramycin (TOB) for the treatment of pneumonia caused by Pseudomonas aeruginosa in rabbits. Treatments were humanised and mimicked intermittent CAZ (iCAZ) (2g three times daily), continuous CAZ (cCAZ) (4g once daily (qd)) and TOB (10mg/kg qd). Minimum inhibitory concentrations (MICs) were 1mg/L and 4mg/L for TOB and CAZ, respectively. Bacterial efficacy in lungs was as follows: control, 9+/-0.6 colony-forming units (CFU)/g; TOB monotherapy, 8+/-0.5CFU/g; iCAZ monotherapy, 7.8+/-1.4CFU/g; cCAZ monotherapy, 8+/-0.4CFU/g (P = 0.005); and iCAZ+TOB, 8+/-0.5CFU/g; cCAZ+TOB, 7.2+/-…