Publications by authors named "Sara Nageeb El-Helaly"

Telomerase enzyme prevents telomere shortening during division, having human telomerase reverse transcriptase (hTERT) as its catalytic subunit. Favipiravir (FAV), an RNA-dependent RNA polymerases inhibitor, shared structural similarity with hTERT and thus assumed to have cytotoxic effect on cancer cells, in addition to its prophylactic effect to immunocompromised cancer patients. Nanoemulsion (NE) is a potential tumor cells targeting delivery system, thereby enhancing therapeutic efficacy at the intended site, mitigating systemic toxicity, and overcoming multidrug resistance.

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Autophagy is a crucial process involved in the degradation and recycling of cytoplasmic components which are transported to the lysosomal compartment by autophagosomes. Exosomes are an important means of communication and signaling in both normal and diseased states, and they have a significant role in the transmission and propagation of proteins, especially proteins implicated in neurodegenerative disorders. Autophagy may affect exosomal processing, but whether autophagy controls the release of aggregated β-amyloid and tau proteins in exosomes of Alzheimer disease (AD) is unclear.

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Major depression is a prevalent disorder characterized by sadness, lack of interest or pleasure, interrupted sleep or food, and impaired concentration. Mirtazapine (MTZ), a tetracyclic antidepressant drug, is commonly used to treat moderate to severe depression. MTZ is classified as a BCS class II drug that has shown bioavailability of 50% due to extensive first-pass metabolism.

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The first melatonergic antidepressant drug, agomelatine (AGM), is commonly used for controlling major depressive disorders. AGM suffers low (< 5%) oral bioavailability owing to the hepatic metabolism. The current work investigated the potential of low-frequency sonophoresis on enhancing transdermal delivery of AGM-loaded novasomes and, hence, bioavailability of AGM.

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Green nanotechnology utilizes the principles of green chemistry to formulate eco-friendly nanocarrier systems to mitigate patients and environment hazards. Raloxifene (RLX) demonstrates poor aqueous solubility (BCS class II) and low bioavailability, only 2% (extensive first-pass metabolism). The aim of this study is to enhance RLX solubility and bioavailability via development of novel solid dispersed multilayered core-sheath RLX-loaded nanofibers (RLX-NFs) without the involvement of organic solvents.

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Aim: Agomelatine (AGM) is the first melatonergic antidepressant. It suffers from low oral bioavailability (<5%) due to extensive hepatic metabolism. The current work aimed to develop an alternative AGM-loaded invasomes to enhance transdermal drug bioavailability.

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Hypertension shows circadian blood pressure rhythms (day-night pattern) that urge the delivery of antihypertensive drugs at the right time in the desired levels. Thus, a bilayered core-in-cup buccoadhesive tablet was formulated that immediately releases olmesartan, to give a burst effect, and controls azelnidipine release, to prolong its therapeutic effect. The main challenge was the poor bioavailability of azelnidipine due to its poor aqueous solubility and first-pass effect.

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The aim of this research was to formulate a novel nano-micellar complex carrier with intrinsically enhanced intestinal permeability for rosuvastatin calcium (RSV); as a model of BCS class III active pharmaceutical ingredients (APIs). The model drug is used primarily for treating hypercholesterolemia. Three phospholipid types with different degrees of saturation were chosen for the study.

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Reduced bioavailability of azelnidipine is related to its poor aqueous solubility and extensive first-pass metabolism, which hinder its efficacy. These problems were addressed by implementing (1) a liquisol technique for promoting the dissolution rate in a controlled-release manner and (2) a core-in-cup bucco-adhesive drug delivery system as an alternative to the oral route. A 33 factorial design was used to study the effects of polymer type (sodium carboxymethyl cellulose (CMC Na), chitosan, or Carbomer P940) concentration (5, 10 or 15 %) and preparation technique (simple mix, liquisol or wet granulation) on the dissolution and mucoadhesion of core-in-cup azelnidipine buccoadhesive tablets.

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The study aimed to fabricate innovative drug-phospholipid complexes termed "sonocomplexes" adopting ultrasound irradiation to increase the liposolubility and to enhance the intestinal absorption of rosuvastatin as a model drug for BCS class III active pharmaceutical ingredients (APIs). A 2 full factorial design was fashioned to investigate the influence of phosphatidylcholine content in the phospholipid (∼30 and 60%) and molar ratio of phospholipid to rosuvastatin (1:1 and 2:1) on physicochemical properties of sonocomplexes. In comparison to pure drug, sonocomplexes showed a minimum of about 2 folds and a maximum of about 15 folds increase in lipophilicity (expressed in terms of partition coefficient, P).

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This study aims to investigate factors affecting weakly basic drugs liposomal systems. Resolution V fractional factorial design (2) is used as an example of screening designs that would better be used as a wise step before proceeding with detailed factors effects or optimization studies. Five factors probable to affect liposomal systems of weakly basic drugs were investigated using Amisulpride as a model drug.

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Intranasal zaleplon solid dispersion was formulated to enhance the solubility, bioavailability and deliver an effective therapy. Zaleplon belongs to Class II drugs, and undergoes extensive first-pass metabolism after oral absorption exhibiting 30% bioavailability. A 2 full-factorial design was chosen for the investigation of solid dispersion formulations.

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Background: Zaleplon is a pyrazolopyrimidin derivative hypnotic drug indicated for the short-term management of insomnia. Zaleplon belongs to Class II drugs, according to the biopharmaceutical classification system (BCS), showing poor solubility and high permeability. It undergoes extensive first-pass hepatic metabolism after oral absorption, with only 30% of Zaleplon being systemically available.

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Being one of the highly effective drugs in treatment of Alzheimer's disease, Rivastigmine brain targeting is highly demandable, therefore liposomal dispersion of Rivastigmine was prepared containing 2 mol% PEG-DSPE added to Lecithin, Didecyldimethyl ammonium bromide (DDAB), Tween 80 in 1:0.02:0.25 molar ratio.

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