There is a lack of a standardized tool for adherence measurement in patients with epilepsy. Studies in children with epilepsy have reported adherence in 50-96.5%. The primary objective of this study was to identify predictors of nonadherence to antiepileptic drugs (AEDs) using two different methods in Jordanian children and adolescents with epilepsy. Participants included 63 children and adolescents with epilepsy and their primary caregivers. Adherence measures included a subjective approach (using parent and child self-reports via Medication Adherence Report Scale (MARS)) and an objective method (measuring plasma levels of AEDs coupled with the application of population pharmacokinetic models to predict AED concentrations in the children). The Beliefs about Medicines Questionnaire (BMQ) was used to examine the association beliefs about medicines with nonadherence in the participating patients. Measuring AEDs in plasma samples captured the highest percentage of nonadherence (36.2%). No significant agreement was found between the AED plasma level method and both the MARS (parent) and MARS (child). The overall nonadherence (combined methods) to AED therapy in children with epilepsy was 44.4%. Logistic regression analysis indicated that children with longer duration of disease were more likely (odds ratio [OR]: 1.54, 95% confidence interval [CI]: 1.16-2.04) to be classified as nonadherent as were children whose parents have lower AED Necessity scores (OR: 0.68, 95% CI: 0.53-0.87) and higher AED Concerns (OR: 1.6, 95% CI: 1.26-2.04) as measured by the BMQ. The use of a multimethod approach for assessing adherence increases sensitivity for detection of nonadherence to AEDs. Disease duration and parental necessity beliefs and concerns assessed by the BMQ-specific questionnaire were significant predictors of nonadherence to the AED therapy. The need for the development and implementation of interventions that can be employed to improve adherence within this pediatric population has been highlighted by the high levels of nonadherence identified.
Insulin mucoadhesive buccal films (MBF) are a noninvasive insulin delivery system that offers an advantageous alternative route of administration to subcutaneous injection. One major concern in the formulation of insulin MBF is the preservation of an insulin secondary structure in the presence of the other film components. Buccal films were formulated using chitosan, glycerin, and L-arginine. The MBF-forming solutions (MBF-FS) and the films (MBF) were examined for their chemical and structural stability and for their in vivo activity. Enzyme-Linked Immunosorbent Assay (ELISA) of the insulin-loaded MBF showed that each individualized unit dose was at least loaded with 80% of the insulin theoretical dose. Results of Synchrotron Radiation Circular Dichroism (SRCD) measurements revealed that MBF-FS retained the α-helices and β–sheets conformations of insulin. Fourier transform infrared (FTIR)-microspectroscopy (FTIR-MS) examination of insulin MBF revealed the protective action of L-arginine on insulin structure by interacting with chitosan and minimizing the formation of an unordered structure and β-strand. A blood glucose-lowering effect of insulin MBF was observed in comparison with subcutaneous (S.C) injection using a rat model. As a result; chitosan-based MBFs were formulated and characterized using SRCD and FTIR-MS techniques. Furthermore, the results of in vivo testing suggested the MBFs as a promising delivery system for insulin.
2 December 2018 in Drug Development and Industrial Pharmacy
Objective: To study the potential influence of selected metal ions on absorption (and hence oral bioavailability of ciprofloxacin (Cipro) in presence and absence of a competing ligand. Significance: The presence of metal ions together with Cipro results in complexes exhibiting a decreased bioavailability. Attempts were made to better understand the mechanism of decreased Cipro bioavailability in the presence of metals such as calcium and ferrous ions, and a small-sized ligand citric acid (CitA). Methods: Effect of complex size or other potential factors was studied using diffusion through synthetic membrane, permeation studies across Caco-2 cells and capillary electrophoresis. A molecular dynamics (MD) simulation study was conducted to find the arrangement and the nature of the interactions between Cipro molecules and ferrous ions. Results: Cipro was shown to form complexes with metals and CitA. The presence of CitA improved permeation of Cipro through the synthetic membrane but this was not as obvious in case of Caco-2 cells. Capillary electrophoresis suggested the existence of large molecular aggregates of Cipro: metal complexes. MD simulations offered clear evidence of large size aggregates in line with the experimental findings. CitA alone significantly improved permeation of Cipro through Caco-2 cells. Conclusions: The size of the formed complexes, rather than the decrease in the solubility of formed complexes, plays a significant role in permeation (absorption) of Cipro. CitA might ameliorate the effect of co-administered metal ions on the bioavailability of Cipro.
Twenty-five structurally diverse compounds have been tested in vitro for their pancreatic lipase (PL) inhibitory activity. Despite the diversity of tested compounds, the relationship comprising structural attributes of the compounds could be established to correlate with the observed inhibitory activity. Compounds that exerted inhibitory action through surface activity were of different profile from the rest of compounds. When co-incubated with orlistat (OsT), important synergistic effects for some compounds (orphenadrine, gliclazide, cefuroxime and sulfacetamide) were revealed, while antagonistic effects were demonstrated for others (camphor sulfonic acid and dinitro salicylic acid). Docking studies for the most active molecules were performed and molecular interaction forces with the PL active site were identified. The results suggested co-binding of OsT along with the other inhibitor in the binding site in cases of synergistic effect but not in the case of antagonistic effect. These results were additionally supported by affinity capillary electrophoresis. In conclusion, synergistic lipase inhibitory activity between OsT and some other pharmaceutical compounds was demonstrated for the first time, which might help improve the pharmacological effect of OsT.
7 February 2017 in Journal of Liquid Chromatography & Related Technologies
Determination of residual pharmaceutical compounds in environmental water is gaining increasing interests. The task represents a substantial challenge to analysts because analytes present in quite complicated matrices and at very low concentrations. Despite the inherent low sensitivity associated with capillary electrophoresis (CE), it has been used successfully to determine different types of pharmaceutical compounds at very low levels that rival those reported by more commonly used methods for that purpose such as high performance liquid chromatography-mass spectrometry (HPLC-MS). Attempts to use CE for the determination of drugs in environmental water samples started nearly in the late 1990s; since then, different modes of CE including capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography together with different detection techniques (UV, fluorescence, MS) have been investigated and shown to be of adequate performance. A key to the success of CE for such low-level determination was the sample concentration steps that have been used including solid-phase extraction and more advanced approaches such as in-line sample concentration, large volume sample stacking, and others. The different reports that have been reported for this application in particular have been reviewed since late 1990s with emphasis on the attained limits of detections and sample treatment. The particularities of the separation conditions in each case have been discussed with some elaboration. GRAPHICAL ABSTRACT
1 January 2017 in Journal of Analytical Methods in Chemistry
Levetiracetam (LVT) is a widely used antiepileptic drug (AED). A less invasive sampling method for therapeutic drug monitoring (TDM) would be very useful particularly for children. Saliva has been shown as an adequate sample for TDM of some AEDs. Due to the high hydrophilicity of LVT its separation on common stationary phases is quite a challenge so that previous methods for determination of LVT in saliva employed either gradient high performance liquid chromatographic (HPLC) system or mass spectrometer as a detector. In this study the retention behavior of LVT on some common stationary phases was examined, with C8 being the most retentive. A simple isocratic HPLC method that is based on simple protein precipitation was developed and validated for the determination of LVT in saliva. The method was applied to a sample group of epileptic children for the purpose of assessing potential correlation with plasma LVT levels and to investigate patient’s compliance. The results confirmed a reasonable correlation between plasma and salivary levels of LVT ( = 0.9) which supports the use of saliva for TDM of LVT. The study also revealed a significant percentage of epileptic patients having LVT levels below the estimated therapeutic range.