Search results for "kinetics"
showing 10 items of 2224 documents
Experimental visualization of inoculation using a charged colloidal model system
2012
Inoculation is widely used to tune the microstructure of a polycrystalline solid from the melt and thus its material properties. We present here a systematic time resolved experimental study of inoculation in a charged colloidal model system investigating the changes of the crystallization scenario upon adding spherical seeds and show that the nucleation kinetics solely determines the resulting microstructure.
Kinetic and equilibrium studies for the adsorption of acid nucleic bases onto K10 montmorillonite
2011
Abstract The kinetic of the adsorption of two nucleic acid bases, namely adenine (A) and cytosine (C), on K10 montmorillonite (MMT) clay has been investigated over a wide range of nitrogenous bases concentrations, by using the spectrophotometric method. The measurements have been performed at T = 25.0 °C and pH = 4.0 where adenine and cytosine exist both in their protonated and neutral forms. Preliminary to the kinetic data treatment, the adsorption isotherms have been gathered and, then, analyzed by using the Freundlich and the Dubinin–Radushkevich model. The obtained results allow to draw the conclusion that physisorption of adenine and cytosine on MMT occurs and the process is mainly gov…
Effect of carbendazim and physicochemical factors on the growth and ochratoxin A production of Aspergillus carbonarius isolated from grapes.
2007
Carbendazim is a systemic fungicide that is commonly used on several crops (tobacco, fruit, vegetables, cereals, etc.). This fungicide is used to control fungal infections in vineyards. It is indicated against Botrytis cinerea, Uncinula necator, Plasmopara viticola and other fungi and can be used either alone or coupled with other fungicides. However, there is a lack of in-depth studies to evaluate its effectiveness against growth of Aspergillus carbonarius isolated from grapes and OTA production. A medium based on red grape juice was used in this study. Preliminary studies were performed at 0.98 a(w) and 25 degrees C using carbendazim concentrations over a wide range (1-2000 ng/ml medium) …
The usefulness of Olanzapine plasma concentrations in monitoring treatment efficacy and metabolic disturbances in first-episode psychosis
2021
Introduction: The role of Olanzapine therapeutic drug monitoring is controversial. The present study explores the associations of Olanzapine plasma concentrations with clinical response and metabolic side effects in first episode psychosis (FEP) after 2 months of treatment. Methods: Forty-seven patients were included. Improvement in clinical symptomatology was assessed using the PANSS. Metabolic assessment included weight, blood pressure, waist circumference, blood glucose, total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides. Results: The Olanzapine plasma concentrations after 2 months of treatment were positively correlated with weight gain (r = 0.49, p …
Fluvoxamine but not sertraline inhibits the metabolism of olanzapine: evidence from a therapeutic drug monitoring service.
2001
Therapeutic drug monitoring data of the new atypical neuroleptic drug olanzapine were used to study interactions with the selective serotonin reuptake inhibitors fluvoxamine and sertraline. The distribution of the ratio of concentration/daily dose (C/D; ng/mL per mg/d) of olanzapine was compared in three groups: patients treated with olanzapine (n = 134), patients treated with olanzapine plus fluvoxamine (n = 10) concomitantly, and patients treated with olanzapine plus sertraline (n = 21) concomitantly. No significant difference was seen between the olanzapine and the olanzapine plus sertraline groups. Patients receiving fluvoxamine in addition to olanzapine had C/D ratios that were in the …
Fluvoxamine augmentation of olanzapine in chronic schizophrenia: pharmacokinetic interactions and clinical effects.
2002
Olanzapine is a substrate of the cytochrome P450 enzyme (CYP) 1A2. In this study, pharmacokinetic interactions and clinical effects of adding the CYP1A2 inhibitor fluvoxamine to steady-state olanzapine was examined in patients suffering from schizophrenia. Eight patients had been treated for at least 3 months with 10 to 20 mg/day olanzapine. Fluvoxamine (100 mg/day) was added (week 0) to the olanzapine treatment and continued for 8 weeks. Concentrations of olanzapine and its metabolite N-desmethylolanzapine and of fluvoxamine were analyzed at weeks 0, 1, 4, and 8. Addition of fluvoxamine resulted in a 12% to 112% (0.01) increase of olanzapine from 31 +/- SD 15 ng/mL (week 0) to 56 +/- 31 ng…
Safety and Pharmacokinetics/Pharmacodynamics of the First-in-Class Dual Action HER3/EGFR Antibody MEHD7945A in Locally Advanced or Metastatic Epithel…
2015
Abstract Purpose: The novel dual-action humanized IgG1 antibody MEHD7945A targeting HER3 and EGFR inhibits ligand-dependent HER dimer signaling. This phase I study evaluated the safety, pharmacokinetics, pharmacodynamics, and antitumor activity of MEHD7945A. Experimental Design: Patients with locally advanced or metastatic epithelial tumors received escalating doses of MEHD7945A (1–30 mg/kg) every 2 weeks (q2w) until disease progression or intolerable toxicity. An expansion cohort was enrolled at the recommended phase II dose (14 mg/kg, q2w). Plasma samples, tumor biopsies, FDG-PET were obtained for assessment of pharmacokinetics, and pharmacodynamic modulation downstream of EGFR and HER3. …
Population pharmacokinetic model of lithium and drug compliance assessment.
2016
Population pharmacokinetic analysis of lithium during therapeutic drug monitoring and drug compliance assessment was performed in 54 patients and 246 plasma concentrations levels were included in this study. Patients received several treatment cycles (1-9) and one plasma concentration measurement for each patient was obtained always before starting next cycle (pre-dose) at steady state. Data were analysed using the population approach with NONMEM version 7.2. Lithium measurements were described using a two-compartment model (CL/F=0.41Lh-1, V1/F=15.3L, Q/F=0.61Lh-1, and V2/F = 15.8L) and the most significant covariate on lithium CL was found to be creatinine clearance (reference model). Lith…
Efficacy of weekly low-dose chemotherapy in elderly women with advanced ovarian cancer: is there an antiangiogenic effect?
2006
13133 Background: In elderly patients decreased functionality of multiple organ systems may affect pharmacokinetics and pharmacodynamics of drugs. For this reason elderly cancer patients experience enhanced susceptibility to common chemotherapy-related adverse events. A way to prevent these effects could be metronomic chemotherapy, which is a variation of dose-dense therapy, with a cumulative dose significantly lower than maximum tolerated dose. Methods: 27 advanced ovarian cancer patients, median age 67 (range 60–86), received low dose weekly continuous chemotherapy until disease progression. All patients were treated with CBDCA AUC 2 mg/ml/min and Docetaxel 35 mg/sqm (adjusted according …
Administration of cetuximab every 2 weeks in the treatment of metastatic colorectal cancer: an effective, more convenient alternative to weekly admin…
2008
Abstract The primary purpose of this paper is to present the available evidence for the administration of cetuximab on an every-2-weeks basis in combination with irinotecan in metastatic colorectal cancer (mCRC). Cetuximab is an epidermal growth factor receptor–targeted IgG1 monoclonal antibody that is approved for use in combination with irinotecan or as monotherapy in the treatment of mCRC. The currently approved dosing regimen for cetuximab is a 400-mg/m2 initial dose followed by 250 mg/m2 weekly. Many commonly used chemotherapy agents for mCRC (including irinotecan alone or in combination with 5-fluorouracil [5-FU]/folinic acid [FA] and oxaliplatin plus 5-FU/FA) are administered on an e…