Al-Arab Medical University

About: Al-Arab Medical University is a education organization based out in Benghazi, Libya. It is known for research contribution in the topics: Population & Nephrotoxicity. The organization has 311 authors who have published 283 publications receiving 3931 citations.

Skin permeation mechanism and bioavailability enhancement of celecoxib from transdermally applied nanoemulsion.

Abstract: Celecoxib, a selective cyclo-oxygenase-2 inhibitor has been recommended orally for the treatment of arthritis and osteoarthritis. Long term oral administration of celecoxib produces serious gastrointestinal side effects. It is a highly lipophilic, poorly soluble drug with oral bioavailability of around 40% (Capsule). Therefore the aim of the present investigation was to assess the skin permeation mechanism and bioavailability of celecoxib by transdermally applied nanoemulsion formulation. Optimized oil-in-water nanoemulsion of celecoxib was prepared by the aqueous phase titration method. Skin permeation mechanism of celecoxib from nanoemulsion was evaluated by FTIR spectral analysis, DSC thermogram, activation energy measurement and histopathological examination. The optimized nanoemulsion was subjected to pharmacokinetic (bioavailability) studies on Wistar male rats. FTIR spectra and DSC thermogram of skin treated with nanoemulsion indicated that permeation occurred due to the disruption of lipid bilayers by nanoemulsion. The significant decrease in activation energy (2.373 kcal/mol) for celecoxib permeation across rat skin indicated that the stratum corneum lipid bilayers were significantly disrupted (p < 0.05). Photomicrograph of skin sample showed the disruption of lipid bilayers as distinct voids and empty spaces were visible in the epidermal region. The absorption of celecoxib through transdermally applied nanoemulsion and nanoemulsion gel resulted in 3.30 and 2.97 fold increase in bioavailability as compared to oral capsule formulation. Results of skin permeation mechanism and pharmacokinetic studies indicated that the nanoemulsions can be successfully used as potential vehicles for enhancement of skin permeation and bioavailability of poorly soluble drugs.

Sweet’s syndrome: Is the pathogenesis mediated by helper T cell type 1 cytokines?

Abstract: Background: The pathogenesis of Sweet's syndrome (acute febrile neutrophilic dermatosis; SS) is still not fully understood. An imbalance between helper T cell types 1 and 2 cytokine secretion patterns has been shown to be relevant in many diseases. Objective: We assessed the serum cytokine levels (interleukin [IL]-1α, IL-1β, IL-2, interferon gamma [IFN-γ], IL-4) in patients with SS. Methods: Eight patients with SS were analyzed for their clinical features and serum cytokine levels and compared with normal control subjects. Results: In patients serum levels of IL-1α, IL-1β, IL-2, and IFN-γ were significantly elevated, whereas the IL-4 level was within the normal range. Conclusion: Our findings suggest that the pathogenesis of SS is probably mediated through helper T cell type 1 cytokines (IL-2, IFN-γ) rather than helper T cell type 2 cytokines (IL-4). (J Am Acad Dermatol 1998;39:940-3.)

Celecoxib nanoemulsion: Skin permeation mechanism and bioavailability assessment

Abstract: The aim of the present study was to assess the skin permeation mechanism and bioavailability of celecoxib (CXB) using novel nanoemulsion formulation. Fourier transform infrared spectra and differential scanning calorimetric thermogram of skin treated with nanoemulsion indicated that permeation occurred due to the extraction of stratum corneum (SC) lipids by nanoemulsion. The significant decrease in activation energy for CXB permeation across rat skin indicated that the SC lipid bilayers were significantly disrupted (p < 0.05). Photomicrograph of skin sample showed the disruption and extraction of lipid bilayers as distinct voids and empty spaces visible in the epidermal region. The absorption of CXB through transdermally applied nanoemulsion and nanoemulsion gel resulted in 3.03- and 2.65-fold increases in bioavailability when compared with conventional oral capsule formulation. Overall, these findings indicated that nanoemulsions can be successfully used for the enhancement of skin permeation and bioavailability of poorly soluble drugs.