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Areas covered: The multitude of polymers that can be combined with lipids to exert a synergistic effect for oral drug delivery have been identified, reviewed and critically evaluated. Specific focus is attributed to preclinical studies performed within the past 5 years that have elucidated the role and mechanism of the polymer phase in altering the oral absorption of encapsulated therapeutics.
Expert opinion: The potential of PLH systems has been clearly identified; however, improved understanding of the structure–activity relationship between PLH systems and oral absorption is fundamental for translating this promising delivery approach into a clinically relevant formulation. Advancing research within this field to identify optimal polymer, lipid combinations and engineering conditions for specific therapeutics are therefore encouraged. 相似文献
Areas covered: This review was written after detailed search in PubMed, EMBASE, ISI web, SciELO, Scopus, and Cochrane Central Register databases (from 1970 to 2019). It summarized the reported ophthalmologic adverse effects of the currently available AEDs; their risks and possible pathogenic mechanisms. They include ocular motility dysfunctions, retinopathy, maculopathy, glaucoma, myopia, optic neuropathy, and impaired retinal vascular autoregulation. In general, ophthalmo-neuro- or retino-toxic adverse effects of AEDs are classified as type A (dose-dependent), type B (host-dependent or idiosyncratic) or type C which is due to the cumulative effect from long-term use.
Expert opinion: Ocular adverse effects of AEDs are rarely reviewed although some are frequent or may result in permanent blindness. Increasing knowledge of their incidence and improving understanding of their risks and pathogenic mechanisms are crucial for monitoring, prevention, and management of patients’ at risk. 相似文献
Background
To assess the effects of 5-(3-chlorobenzyl)-4-hexyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (TP427) on the protective anticonvulsant action of four classical antiepileptic drugs (carbamazepine, phenobarbital, phenytoin and valproate) in the tonic-clonic seizure model in mice, an isobolographic transformation of data was used.Methods
Electrically-induced tonic-clonic seizures were experimentally evoked in adult male albino Swiss mice. The anticonvulsant effects of TP427, when used singly, were determined by the calculation of the threshold increasing the dose by 20% (TID20 value). The influence of TP427 on the anticonvulsant potency of four various classical antiepileptic drugs was determined with a subthreshold method. Types of interactions between drugs were determined using the isobolographic transformation of data. Additionally, total brain antiepileptic drug concentrations were measured.Results
TP427, when administered separately, significantly increased the threshold for electroconvulsions. The experimentally determined TID20 value for TP427 was 11.71?mg/kg. Moreover, TP427 (10?mg/kg) significantly increased the anticonvulsant activity of valproate (p?<? 0.01), but not that of carbamazepine, phenobarbital or phenytoin in the mouse tonic-clonic seizure model. Isobolographic transformation of data confirmed that the interaction between TP427 and valproate was synergistic. Pharmacokinetic study revealed that TP427 increased total brain valproate concentrations, and had no impact on total brain concentrations of carbamazepine, phenobarbital or phenytoin in mice.Conclusion
The synergistic interaction between TP427 and valproate in the mouse tonic-clonic seizure model might occur favorable for epilepsy patients in future. The combinations of TP427 with carbamazepine, phenobarbital and phenytoin were additive in the mouse tonic-clonic seizure model and also deserves clinical attention. 相似文献Conjugation with the tripeptide glutathione (GSH) is a common mechanism of detoxification of many endogenous and exogenous compounds. This phenomenon typically occurs through the formation of a covalent bond between the nucleophilic free thiol moiety of GSH and an electrophilic site on the compound of interest.
While GSH adducts have been identified for many licit drugs, there is a lack of information on the ability of drugs of abuse to adduct GSH. The present study utilized a metabolic assay with GSH as a nucleophilic trapping agent to bind reactive drug metabolites formed in situ.
Extracted ion MS spectra were collected via LC-QqQ-MS/MS for all potentially significant ions and examined for fragmentation common to GSH-containing compounds, followed by confirmation of adduction and structural characterization performed by LC-QTOF-MS/MS.
In addition to the two positive controls, of the 14 drugs of abuse tested, 10 exhibited GSH adduction, with several forming multiple adducts, resulting in a total of 22 individual identified adducts. A number of these are previously unreported in the literature, including those for diazepam, naltrexone, oxycodone and Δ9-THC.