Formulation, characterization and in vivo evaluation of novel edible dosage form containing nebivolol HCl

ABSTRACT The objective of this investigation was to develop a novel oral edible gel dosage form for nebivolol hydrochloride, with suitable rheological characteristics that can provide a means of administering the drug to dysphagic and geriatric patients. Edible gels were prepared using low acetylated gellan gum and sodium citrate in different concentrations. The effect of concentration of the solution on gelation time, viscosity, and drug release was studied. Optimized formulation had "spoon thick" consistency that is considered suitable for dysphagic patients as suggested by National Dysphagia Diet Task Force. The optimized formulation containing gellan gum (0.4 % w/v) and sodium citrate (0.3 % w/v) showed more than 95% drug release in 20 minutes. This formulation also showed significantly better pharmacokinetic profile when compared to marketed conventional tablets in New Zealand white rabbits (n = 3). Optimized formulation was found stable for 6 months when stored at 25 °C ± 0.2 °C/60 ± 5% RH. From this study, it can be concluded that the novel edible gel dosage form containing nebivolol hydrochloride may prove to be more efficacious in the treatment of hypertension in dysphagic patients

Functional characterization of the HD-ZIP IV transcription factor OCL1 from maize

OCL1 (OUTER CELL LAYER1) encodes a maize HD-ZIP class IV transcription factor (TF) characterized by the presence of a homeo DNA-binding domain (HD), a dimerization leucine zipper domain (ZIP), and a steroidogenic acute regulatory protein (StAR)-related lipid transfer domain (START) involved in lipid transport in animals but the function of which is still unknown in plants. By combining yeast and plant trans-activation assays, the transcriptional activation domain of OCL1 was localized to 85 amino acids in the N-terminal part of the START domain. Full-length OCL1 devoid of this activation domain is unable to trans-activate a reporter gene under the control of a minimal promoter fused to six repeats of the L1 box, a cis-element present in target genes of HD-ZIP IV TFs in Arabidopsis. In addition, ectopic expression of OCL1 leads to pleiotropic phenotypic aberrations in transgenic maize plants, the most conspicuous one being a strong delay in flowering time which is correlated with the misexpression of molecular markers for floral transition such as ZMM4 (Zea Mays MADS-box4) or DLF1 (DELAYED FLOWERING1). As suggested by the interaction in planta between OCL1 and SWI3C1, a bona fide subunit of the SWI/SNF complex, OCL1 may modulate transcriptional activity of its target genes by interaction with a chromatin remodelling complex. © 2010 The Author