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The interactions between cellulose nanocrystals and six different polymers (three anionic, two non-ionic, and one cationic) were investigated using rheological measurements of aqueous solutions of nanocrystals and polymers. The experimental viscosity data could be described adequately by a power-law model. The variations in power-law parameters (consistency index and flow behavior index) with concentrations of nanocrystals and polymers were determined for different combinations of nanocrystals and polymers. The interactions between nanocrystals and the following polymers: anionic sodium carboxymethyl cellulose and non-ionic guar gum, were found to be strong in that the consistency index increased substantially with the addition of nanocrystals to polymer solutions. The interaction between nanocrystals and non-ionic polymer polyethylene oxide was moderate. Depending on the concentrations of nanocrystals and polymer, the consistency index both increased and decreased upon the addition of nanocrystals to polymer solution. The interactions between nanocrystals and the following polymers: anionic xanthan gum, anionic polyacrylamide, and cationic quaternary ammonium salt of hydroxyethyl cellulose, were found to be weak. The changes in rheological properties with nanocrystal addition to these polymer solutions were found to be small or negligible.

Poor aqueous solubility besides extensive hepatic first effect significantly decreases the oral absorption of levosulpiride, which in turn minimizes its therapeutic effectiveness. Niosomes have been extensively investigated as a transdermal vesicular nanocarrier to increase the delivery of low permeable compounds into and across the skin. This research work was to design, develop and optimize levosulpiride-loaded niosomal gel and to evaluate its prospects for transdermal delivery. The Box-Behnken design was used to optimize niosomes by analyzing the impact of three factors (cholesterol; X1, Span 40; X2, and sonication time; X3) on the responses (particle size, Y1, and entrapment efficiency, Y2). Optimized formulation (NC) was incorporated into gel and evaluated for pharmaceutical properties, drug release study, ex vivo permeation, and in vivo absorption. The design experiment data suggest that all three independent variables influence both response variables significantly (p < 0.01). Pharmaceutical characteristics of NC vesicles showed the absence of drug excipient interaction, nanosize (~102.2 nm), narrow distribution (~0.218), adequate zeta potential (−49.9 mV), and spherical shape, which are suitable for transdermal therapy. The levosulpiride release rates varied significantly (p < 0.01) between niosomal gel formulation and control. Greater flux (p < 0.01) was observed with levosulpiride-loaded niosomal gel than with control gel formulation. Indeed, the drug plasma profile of niosomal gel was significantly higher (p < 0.005), with ~3 folds higher Cmax and greater bioavailability (~500% higher; p < 0.0001) than its counterpart. Overall, these findings imply that the use of an optimized niosomal gel formulation can increase the therapeutic efficacy of levosulpiride and may represent a promising alternative to conventional therapy.

Only a small subset of all the transcribed RNAs are used as a template for protein translation, whereas RNA molecules that are not translated play a very important role as regulatory non-coding RNAs (ncRNAs). Besides traditionally known RNAs (ribosomal and transfer RNAs), ncRNAs also include small non-coding RNAs (sncRNAs) and long non-coding RNAs (lncRNAs). The lncRNAs, which were initially thought to be junk, have gained a great deal attention because of their regulatory roles in diverse biological processes in animals and plants. Insects are the most abundant and diverse group of animals on this planet. Recent studies have demonstrated the role of lncRNAs in almost all aspects of insect development, reproduction, and genetic plasticity. In this review, we describe the function and molecular mechanisms of the mode of action of different insect lncRNAs discovered up to date.