Aliaa Nabil ElMeshad

Bio: Aliaa Nabil ElMeshad is an academic researcher from Cairo University. The author has contributed to research in topics: Bioavailability & Medicine. The author has an hindex of 16, co-authored 41 publications receiving 680 citations. Previous affiliations of Aliaa Nabil ElMeshad include Al-Azhar University & The Chinese University of Hong Kong.

Enhanced corneal permeation and antimycotic activity of itraconazole against Candida albicans via a novel nanosystem vesicle.

Abstract: The objective of this study was to investigate the potential of spanlastics as an ophthalmic delivery system to improve the corneal permeability and antimycotic activity of itraconazole (ITZ). Spanlastics containing edge activators, including Tween 20 or 80, were produced by modified ethanol injection method and exhibited a particle size of approximately 287 nm and an entrapment efficiency of more than 88%. Less than 13% ITZ was released from spanlastics over 6 h compared to 35% from conventional niosomes. Spanlastics exerted a 1.34-fold increase in the amount of ITZ permeated through excised bovine cornea after 24 h compared to conventional niosomes. Antimycotic study revealed a significant (p < 0.05) increase in the zone of inhibition of Candida albicans culture demonstrated by spanlastics compared to ITZ powder at the same concentration level (10 mg). In vivo Draize test showed no signs of acute ocular toxicity upon application of the selected spanlastic formulation to the rabbit eye. Results r...

Characterization and Optimization of Orodispersible Mosapride Film Formulations

Abstract: Orodispersible film (ODF) technology offers new possibilities for drug delivery by providing the advantages of oral delivery coupled with the enhanced onset of action and convenience to special patient categories such as pediatrics and geriatrics. In this study, mosapride (MOS) was formulated in an ODF preparation that can be used for treatment of patients who suffer from gastrointestinal disorders, especially difficulty in swallowing due to gastroesophageal reflux disease. Poloxamer 188 was used to solubilize MOS to allow its incorporation into the film matrix. The films were prepared by solvent-casting method using different polymer ratios of maltodextrin and hydroxypropyl methylcellulose and plasticizer levels of glycerol and propylene glycol. A D-optimal design was utilized to study the effect of polymer ratio, plasticizer type, and level on film mechanical properties, disintegration time, and dissolution rate. Statistical analysis of the experimental design showed that the increase of maltodextrin fraction and plasticizer level conferred optimum attributes to the prepared films in terms of film elasticity, film disintegration time, and MOS release rate. The ODF formulations were further tested for moisture sorption capacity, with formulations containing a higher ratio of maltodextrin and percent plasticizer showing more moisture uptake. The optimum film composition was also tested in vivo for film palatability and disintegration time. An optimized mosapride orodispersible film formulation was achieved that could be of benefit to patients suffering from gastrointestinal disorders.

Potential therapeutic effect of nanobased formulation of rivastigmine on rat model of Alzheimer&#39;s disease

Abstract: Background To sustain the effect of rivastigmine, a hydrophilic cholinesterase inhibitor, nanobased formulations were prepared. The efficacy of the prepared rivastigmine liposomes (RLs) in comparison to rivastigmine solution (RS) was assessed in an aluminium chloride (AlCl(3))-induced Alzheimer's model. Methods Liposomes were prepared by lipid hydration (F1) and heating (F2) methods. Rats were treated with either RS or RLs (1 mg/kg/day) concomitantly with AlCl(3) (50 mg/kg/day). Results The study showed that the F1 method produced smaller liposomes (67.51 ± 14.2 nm) than F2 (528.7 ± 15.5 nm), but both entrapped the same amount of the drug (92.1% ± 1.4%). After 6 hours, 74.2% ± 1.5% and 60.8% ± 2.3% of rivastigmine were released from F1 and F2, respectively. Both RLs and RS improved the deterioration of spatial memory induced by AlCl(3), with RLs having a superior effect. Further biochemical measurements proved that RS and RLs were able to lower plasma C-reactive protein, homocysteine and asymmetric dimethy-larginine levels. RS significantly attenuated acetylcholinesterase (AChE) activity, whereas Na(+)/K(+)-adenosine triphosphatase (ATPase) activity was enhanced compared to the AlCl(3)-treated animals; however, RLs succeeded in normalization of AChE and Na(+)/K(+) ATPase activities. Gene-expression profile showed that cotreatment with RS to AlCl(3)-treated rats succeeded in exerting significant decreases in BACE1, AChE, and IL1B gene expression. Normalization of the expression of the aforementioned genes was achieved by coadministration of RLs to AlCl(3)-treated rats. The profound therapeutic effect of RLs over RS was evidenced by nearly preventing amyloid plaque formation, as shown in the histopathological examination of rat brain. Conclusion RLs could be a potential drug-delivery system for ameliorating Alzheimer's disease.

Comparative Study on the Effects of Some Polyoxyethylene Alkyl Ether and Sorbitan Fatty Acid Ester Surfactants on the Performance of Transdermal Carvedilol Proniosomal Gel Using Experimental Design

Abstract: The aim of this work was to investigate the effects of formulation variables on development of carvedilol (CAR) proniosomal gel formulations as potential transdermal delivery systems Different non-ionic surfactants; polyoxyethylene alkyl ethers, namely Brij 78, Brij 92, and Brij 72; and sorbitan fatty acid esters (Span 60) were evaluated for their applicability in preparation of CAR proniosomal gels A 23 full factorial design was employed to evaluate individual and combined effects of formulation variables, namely cholesterol content, weight of proniosomes, and amount of CAR added on performance of proniosomes Prepared proniosomes were evaluated regarding entrapment efficiency (EE%), vesicle size, and microscopic examination Also, CAR release through cellulose membrane and permeation through hairless mice skin were investigated Proniosomes prepared with Brij 72 and Span 60 showed better niosome forming ability and higher EE% than those prepared with Brij 78 and Brij 92 Higher EE% was obtained by increasing both weight of proniosomes and amount of CAR added, and decreasing cholesterol content Release rate through cellulose membrane was inversely affected by weight of proniosomes In Span 60 proniosomes, on increasing percent of cholesterol, a decrease in release rate was observed While in Brij 72 proniosomes, an enhancement in release rate was observed on increasing amount of CAR added Permeation experiments showed that skin permeation was mainly affected by weight of proniosomes and that Span 60 proniosomal gels showed higher permeation enhancing effect than Brij 72 Proniosomal gel could constitute a promising approach for transdermal delivery of CAR

Enhancement of dissolution and oral bioavailability of lacidipine via pluronic P123/F127 mixed polymeric micelles: formulation, optimization using central composite design and in vivo bioavailability study.

Abstract: This study aims at preparing and optimizing lacidipine (LCDP) polymeric micelles using thin film hydration technique in order to overcome LCDP solubility-limited oral bioavailability. A two-factor ...

The Design and Analysis of Experiments

Abstract: THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

Stability of chitosan-a challenge for pharmaceutical and biomedical applications.

Abstract: Chitosan—one of the natural multifunctional polymers—due to its unique and versatile biological properties is regarded as a useful compound in medical and pharmaceutical technology. Recently, considerable research effort has been made in order to develop safe and efficient chitosan products. However, the problem of poor stability of chitosan-based systems restricts its practical applicability; thus, it has become a great challenge to establish sufficient shelf-life for chitosan formulations. Improved stability can be assessed by controlling the environmental factors, manipulating processing conditions (e.g., temperature), introducing a proper stabilizing compound, developing chitosan blends with another polymer, or modifying the chitosan structure using chemical or ionic agents. This review covers the influence of internal, environmental, and processing factors on the long-term stability of chitosan products. The aim of this paper is also to highlight the latest developments which enable the physicochemical properties of chitosan-based applications to be preserved upon storage.

The return of a forgotten polymer : Polycaprolactone in the 21st century

Abstract: During the resorbable-polymer-boom of the 1970s and 1980s, polycaprolactone (PCL) was used in the biomaterials field and a number of drug-delivery devices. Its popularity was soon superseded by faster resorbable polymers which had fewer perceived disadvantages associated with long term degradation (up to 3-4 years) and intracellular resorption pathways; consequently, PCL was almost forgotten for most of two decades. Recently, a resurgence of interest has propelled PCL back into the biomaterials-arena. The superior rheological and viscoelastic properties over many of its aliphatic polyester counterparts renders PCL easy to manufacture and manipulate into a large range of implants and devices. Coupled with relatively inexpensive production routes and FDA approval, this provides a promising platform for the production of longer-term degradable implants which may be manipulated physically, chemically and biologically to possess tailorable degradation kinetics to suit a specific anatomical site. This review will discuss the application of PCL as a biomaterial over the last two decades focusing on the advantages which have propagated its return into the spotlight with a particular focus on medical devices, drug delivery and tissue engineering.

Getting into the brain: liposome-based strategies for effective drug delivery across the blood-brain barrier.

Abstract: This review summarizes articles that have been reported in literature on liposome-based strategies for effective drug delivery across the blood-brain barrier. Due to their unique physicochemical characteristics, liposomes have been widely investigated for their application in drug delivery and in vivo bioimaging for the treatment and/or diagnosis of neurological diseases, such as Alzheimer's, Parkinson's, stroke, and glioma. Several strategies have been used to deliver drug and/or imaging agents to the brain. Covalent ligation of such macromolecules as peptides, antibodies, and RNA aptamers is an effective method for receptor-targeting liposomes, which allows their blood-brain barrier penetration and/or the delivery of their therapeutic molecule specifically to the disease site. Additionally, methods have been employed for the development of liposomes that can respond to external stimuli. It can be concluded that the development of liposomes for brain delivery is still in its infancy, although these systems have the potential to revolutionize the ways in which medicine is administered.