In vitro antibacterial activity and in vivo pharmacokinetics of intravenously administered Amikacin-loaded Liposomes for the management of bacterial septicaemia.

Systemic delivery of amikacin is a widely adopted treatment modality for severe infections like sepsis. However, the current course of treatment requires repeated bolus doses of amikacin, prolonged hospitalization, and continuous therapeutic monitoring to manage the severe adverse effects. Amikacin has short half-life, which further challenges the delivery of sufficient systemic concentrations when administered by intravenous route. To solve this issue, novel delivery systems, amikacin liposomes (Ak-lip) were developed and evaluated for its antibacterial efficacy (agar plate diffusion and resazurin microtiter assay) and in vivo drug release in Sprague-Dawley rats. The Ak-lip were prepared by modified thin film hydration method and optimized based on particle size and Zeta potential. The zone of inhibition for Ak-lip and amikacin was found to be 22 mm and 26 mm against Staphylococcus aureus. The minimum inhibitory concentrations (MIC) of amikacin and Ak-lip against Staphylococcus aureus were found to be 3 µg/mL and 9 µg/mL, and for Pseudomonas aeruginosa were 0.6 µg/mL and 0.9 µg/mL respectively. The in vivo pharmacokinetic parameters were determined using Gastroplus™. A significant difference in the pharmacokinetic parameters (AUC, Cmax) was observed between amikacin and Ak-lip. The developed formulation showed good colloidal stability and sustained release profile up to 72 h which can reduce dosing frequency, minimize hospitalization and improve bactericidal activity at lower concentrations paving the path for improved therapeutic interventions in the treatment of sepsis.

Luliconazole-loaded nanostructured lipid carriers for topical treatment of superficial Tinea infections.

Tinea are superficial fungal infections caused by dermatophytes. Luliconazole exhibits highest antifungal activity against Trichophyton spp. which are major causative agents of dermatophytosis. However, luliconazole suffers from drawbacks such as less skin retention, low aqueous solubility and poor skin penetration. To overcome the limitations of luliconazole, nanostructured lipid carriers (NLCs) were formulated. NLCs are better permeation enhancers as they increase skin occlusion and hydration. The selection of various lipids and surfactants was based on the solubility of luliconazole in these components. Luliconazole NLC dispersion was prepared by hot melt emulsification technique followed by probe sonication. The dispersion was incorporated into a gel composed of Sepineo P 600 under magnetic stirring. in vitro antifungal studies were carried out with optimized luliconazole NLC gel, marketed luliconazole cream and control (luliconazole in gel base) against pathogenic Trichophyton rubrum. Ex-vivo diffusion study demonstrated that NLCs incorporated into gel exhibited greater retention on skin. In-vivo skin irritancy study showed no signs of erythema or edema post 24, 48, and 72 h at site of application. In comparison with marketed cream and based on the zone of inhibition diameters, NLC formulation was found to be very effective against Trichophyton rubrum.

H, C and N resonance assignments of the C-terminal domain of the 43 kDa subunit of the chloroplast signal recognition particle.

We report the assignment of a 109 amino acid C-terminal chromo domain of the chloroplast signal recognition particle cpSRP43 subunit. cpSRP43 plays a crucial role in the targeting of light harvesting chlorophyll proteins to the thylakoids.

A method for the prevention of thrombin-induced degradation of recombinant proteins.

A new strategy to prevent degradation of recombinant proteins caused by non-specific cleavage by thrombin is described. We demonstrate that degradation due to non-specific cleavage of recombinant protein mediated by thrombin can be completely prevented by separation of thrombin from the recombinant protein on spin columns packed with heparin-sepharose. This method is generally applicable to all recombinant proteins that require the thrombin for the cleavage of affinity tags for purification. To our knowledge, this is the first report of an efficient and reliable method for the separation of residual thrombin from purified recombinant proteins.

1H, 13C and 15N resonance assignments of the C-terminal domain of the 43 kDa subunit of the chloroplast signal recognition particle.

We report the assignment of a 109 amino acid C-terminal chromo domain of the chloroplast signal recognition particle cpSRP43 subunit. cpSRP43 plays a crucial role in the targeting of light harvesting chlorophyll proteins to the thylakoids.