Search results for "PreP"
showing 10 items of 1334 documents
What drives inhaler prescription for asthma patients? Results from a real-life retrospective analysis
2020
Abstract Background The choice of inhaler device for asthma patients depends upon multiple attributes. We investigated factors that may drive general practitioners (GPs) and respiratory specialists in the prescription of inhaler devices for asthma patients who initiated inhalation therapy. Methods We retrospectively analysed prescriptions by GPs and respiratory specialists to asthma patients commencing inhaled corticosteroid/long-acting β2-agonist combination therapy available as both pressurised metered-dose inhalers (pMDIs) and dry powder inhalers (DPIs). Patient characteristics were compared by device and multivariate analysis was used to model the likelihood of receiving a pMDI as oppos…
Quantitative and qualitative control of antineoplastic preparations: Gravimetry versus HPLC.
2019
This article compares gravimetry vs. high-performance liquid chromatography (HPLC) as quality control (QC) methods for paclitaxel, docetaxel and oxaliplatin preparations. We aimed at assessing the preparation method reliability in our hospital, evaluating compounding accuracy and estimating the influence of personnel training and standardized homogenization on compounding accuracy. Agreement, correlation, concordance, accuracy and precision between methods were evaluated for each drug. Conforming preparation percentages (CPs) at different tolerance limits (TLs) and compounding accuracy were calculated for each method and drug. Compounding accuracy was compared before and after personnel tra…
Matrix solid-phase dispersion microextraction and determination by high-performance liquid chromatography with UV detection of pesticide residues in …
1999
A multiresidue method based on matrix solid-phase dispersion (MSPD) microextraction was studied to determine the carbamate, benfuracarb, and urea insecticides, diflubenzuron, flufenoxuron hexaflumuron and hexythiazox, used in control of citrus pests. Optimisation of different parameters, such as the type of solid support for matrix dispersion, elution solvents and the clean-up step were carried out. The method used 0.5 g of orange sample, C8 bonded silica as MSPD sorbent and dichloromethane as eluting solvent. Recoveries, at spiked concentrations below the maximum residue levels established by Spanish Government, were between 74 and 84% with relative standard deviations ranging from 2 to 4%…
Quality control Fourier transform infrared determination of diazepam in pharmaceuticals
2007
A quality control procedure has been developed for the determination of diazepam in pharmaceuticals using Fourier transform infrared (FTIR) spectroscopy. The method involves the off-line extraction of diazepam with chloroform by sonication and direct determination in the extracts through peak area measurement in the interval between 1672 and 1682 cm(-1) using a baseline correction defined between 1850 and 1524 cm(-1). For standardization it was used an external calibration line established from standard solutions of diazepam in chloroform. The method provides a limit of detection of 0.04 mg per tablet (n=5), a relative standard deviation (R.S.D.) of 0.5% for 5 independent measurements of a …
Pressurized liquid extraction combined with capillary electrophoresis–mass spectrometry as an improved methodology for the determination of sulfonami…
2007
A new analytical method, based on capillary electrophoresis and tandem mass spectrometry (CE-MS2), is proposed and validated for the identification and simultaneous quantification of 12 sulfonamides (SAs) in pork meat. The studied SAs include sulfathiazole, sulfadiazine, sulfamethoxypyridazine, sulfaguanidine, sulfanilamide, sulfadimethoxyne, sulfapyridine, sulfachloropyridazine, sulfisoxazole, sulfasalazine, sulfabenzamide and sulfadimidine. Different parameters (i.e. separation buffer, sheath liquid, electrospray conditions) were optimized to obtain an adequate CE separation and high MS sensitivity. MS2 experiments using an ion trap as analyzer, operating in the selected reaction monitori…
Chromatographic multivariate quality control of pharmaceuticals giving strongly overlapped peaks based on the chromatogram profile
2004
In the present paper, the simultaneous quantification of two analytes showing strongly overlapped chromatographic peaks (alpha = 1.02), under the assumption that both available equipment and training of the laboratory staff are basic, is studied. A pharmaceutical preparation (Mutabase) containing two drugs of similar physicochemical properties (amitriptyline and perphenazine) is selected as case of study. The assays are carried out under realistic working conditions (i.e. routine testing laboratories). Uncertainty considerations are introduced in the study. A partial least squares model is directly applied to the chromatographic data (with no previous signal transformation) to perform quali…
Enantiomeric quality control of antihistamines in pharmaceuticals by affinity electrokinetic chromatography with human serum albumin as chiral select…
2007
The present paper deals with the enantiomeric separation of six antihistaminic enantiomers by affinity electrokinetic chromatography (AEKC)-partial filling technique using human serum albumin (HSA) as chiral selector. A multivariate optimization approach of the most critical experimental variables in enantioresolution, running pH, HSA concentration and HSA plug length (SPL) was carried out since there are interactions between variables that could not be considered in an univariate optimization. The estimated and experimental resolution values obtained for antihistaminic enantiomers varied from 1.13 (for orphenadrine) to 2.15 (for brompheniramine). The optimum experimental conditions for ena…
Biopartitioning micellar chromatoraphy to predict blood to lung, blood to liver, blood to fat and blood to skin partition coefficients of drugs
2009
[EN] Biopartitioning micellar chromatography (BMC), a mode of micellar liquid chromatography that uses micellar mobile phases of Brij35 in adequate experimental conditions, has demonstrated to be useful in mimicking the drug partitioning process into biological systems. In this paper, the usefulness of BMC for predicting the partition coefficients from blood to lung, blood to liver. blood to fat and blood to skin is demonstrated. PLS2 and multiple linear regression (MLR) models based on BMC retention data are proposed and compared with other ones reported in bibliography. The proposed models present better or similar descriptive and predictive capability. (C) 2008 Elsevier B.V. All rights r…
Molecular topology as a novel approach for drug discovery
2012
Molecular topology (MT) has emerged in recent years as a powerful approach for the in silico generation of new drugs. One key part of MT is that, in the process of drug design/discovery, there is no need for an explicit knowledge of a drug's mechanism of action unlike other drug discovery methods.In this review, the authors introduce the topic by explaining briefly the most common methodology used today in drug design/discovery and address the most important concepts of MT and the methodology followed (QSAR equations, LDA, etc.). Furthermore, the significant results achieved, from this approach, are outlined and discussed.The results outlined herein can be explained by considering that MT r…
A topological substructural approach for the prediction of P-glycoprotein substrates
2006
A topological substructural molecular design approach (TOPS-MODE) has been used to predict whether a given compound is a P-glycoprotein (P-gp) substrate or not. A linear discriminant model was developed to classify a data set of 163 compounds as substrates or nonsubstrates (91 substrates and 72 nonsubstrates). The final model fit the data with sensitivity of 82.42% and specificity of 79.17%, for a final accuracy of 80.98%. The model was validated through the use of an external validation set (40 compounds, 22 substrates and 18 nonsubstrates) with a 77.50% of prediction accuracy; fivefold full cross-validation (removing 40 compounds in each cycle, 80.50% of good prediction) and the predictio…