MSA Repository "MSAR"

MSAR University's Digital Repository is a documentation and digitization of all university outcomes that are of effective value in the scientific and academic community and reflects the university's image, work, and effective contribution to society Through MSAR Digital Repository, the university managed to collect, store, archive and publish digital content - including documents, audio files, images and data sets - all in a safe place. MSAR is one of the strongest University Digital Repositories in Egypt and documented in the DSPACE community with its latest versions.

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Novel strategies for vancomycin-resistant Enterococcus faecalis bioflm control: bacteriophage (vB_EfaS_ZC1), propolis, and their combined efects in an ex vivo endodontic model
(BioMed Central Ltd, 2025-04-10) Toka A. Hakim; Bishoy Maher Zaki; Dalia A. Mohamed; Bob Blasdel; Mohamed A. Gad; Mohamed S. Fayez; Ayman El‑Shibiny
Background Endodontic treatment failures are predominantly attributed to Enterococcus faecalis (E. faecalis) infection, a Gram-positive coccus. E. faecalis forms bioflms, resist multiple antibiotics, and can withstand endodontic disinfection protocols. Vancomycin-resistant strains, in particular, are challenging to treat and are associated with serious medical complications. Methods A novel phage, vB_EfaS_ZC1, was isolated and characterized. Its lytic activity against E. faecalis was assessed in vitro through time-killing and bioflm assays. The phage’s stability under various conditions was determined. Genomic analysis was conducted to characterize the phage and its virulence. The phage, propolis, and their combination were evaluated as an intracanal irrigation solution against a 4-week E. faecalis mature bioflm, using an ex vivo infected human dentin model. The antibioflm activity was analyzed using a colony-forming unit assay, feld emission scanning electron microscopy, and confocal laser scanning microscopy. Results The isolated phage, vB_EfaS_ZC1, a siphovirus with prolate capsid, exhibited strong lytic activity against Vancomycin-resistant strains. In vitro assays indicated its efectiveness in inhibiting planktonic growth and disrupting mature bioflms. The phage remained stable under wide range of temperatures (− 80 to 60 °C), tolerated pH levels from 4 to 11; however the phage viability signifcantly reduced after UV exposure. Genomic analysis strongly suggests the phage’s virulence and suitability for therapeutic applications; neither lysogeny markers nor antibiotic resistance markers were identifed. Phylogenetic analysis clustered vB_EfaS_ZC1 within the genus Saphexavirus. The phage, both alone and in combination with propolis, demonstrated potent antibioflm efects compared to conventional root canal irrigation. Conclusion Phage vB_EfaS_ZC1 demonstrates a promising therapy, either individually or in combination with propolis, for addressing challenging endodontic infections caused by E. faecalis
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Development and optimization of lyophilized dry emulsion tablet for improved oral delivery of Ivermectin
(Editions de Sante, 2025-04-18) Eiman Abdalla Madawi; Hanan M. El-Laithy; Nihal Mohamed Elmahdy Elsayyad; Mutasem Rawas-Qalaji; Amjad Alhalaweh; Iman Saad Ahmed
Ivermectin (IVM) is a widely used antiparasitic agent and has been repurposed for the treatment of COVID-19. However, its poor water solubility and low bioavailability present significant challenges, often requiring large doses for therapeutic effectiveness. This poses a burden on patients, as they need to take multiple tablets at once, which is both inconvenient and uncomfortable. This study aims to develop and optimize rapidly disintegrating lyophilized dry emulsion tablets (LDET) containing IVM using a quality by design (QbD) approach to enhance its solubility, dispersibility, wettability, and dissolution rate, thereby improving its absorption and bioavailability following oral administration. Oil-in-water (O/W) emulsions were prepared using sweet almond oil or Miglyol 840 as the oil phase, along with stabilizers. The optimal emulsion was subsequently lyophilized to produce IVMLDET. Tablets’ characteristics were assessed in vitro for their properties including solubility, disintegration, and dissolution, and in vivo in rabbits for their pharmacokinetic (PK) profile. Results indicated a remarkable 600-fold increase in IVM solubility in the optimal emulsion formulation. IVM-LDET significantly enhanced the extent and rate of dissolution compared to raw IVM and the marketed tablet, Iverzine®. Furthermore, the PK profile of IVM from LDET showed a 30 % increase in maximum plasma concentration (Cmax) and area under the curve (AUC), and reduced time to reach maximum concentration (tmax) by 4 h compared to Iverzine® tablets. In conclusion, the developed IVM-LDET formulation presents a promising therapeutic alternative to conventional oral IVM products for treating parasitic or viral infections, potentially leading to improved therapeutic outcomes and patient compliance.
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Economic Complexity Determinants Insights from Sub-Saharan Countries
(Economic Laboratory for Transition Research, 2025-04-10) Mubarak Saad Aldosai; Mai Yasser
The economic complexity is one of the most recent indicators that reflect how trade and changes in exports structure can affect economics. Therefore this study aims at assess the main determinants in economic complexity in the lower income countries in sub-Saharan Africa (SSA). This study depends on the data available on the World Bank and UNCTAD since 1994 till 2017 in selected 13 countries. This paper uses LM unit root test besides the fixed effect, and random effects. The findings show that schooling, NRR and schooling enrollment affect the economic complexity in these countries. Therefore policy makers have to give more attention to diversify the exports and not depend on the primary goods only. On the other hand, these revenues from the exports and FDI have to be directed to poverty eradication. © 2025, Economic Laboratory for Transition Research. All rights reserved.
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Gamma radiation-assisted synthesis of tea tree oil-based chitosan films for active packaging applications
(John Wiley and Sons Ltd, 2025-04-13) Asmaa Sayed; Manar E. Abdel-Raouf; Mikhail Magdy; Ghada A. Mahmoud
Sustainable packaging materials with inherent antimicrobial and antioxidant properties are increasingly demanded for food preservation. In this study, chitosan/polyacrylamide/tea tree oil (CS/PAAm/TTO) films were developed via gamma irradiation, varying both the irradiation dose (10–50 kGy) and the TTO concentration (25–100 μL) to attain an optimized formulation with superior performance. In this regard, the optimization was accomplished via atomic force microscopy (AFM) through assessing the surface morphologies of the films prepared at different irradiation doses, which identified 30 kGy as the optimal irradiation dose for TTO incorporation. On the other hand, comprehensive characterizations using Fourier transfer infrared spectroscopy, x-ray diffraction, thermogravimetric analysis, and contact angle measurements revealed that increasing the irradiation dose and TTO content enhanced hydrophobicity and improved mechanical properties. More specifically, the contact angle increased significantly at higher TTO levels, indicating an increased surface hydrophobicity, while tensile tests demonstrated improved flexibility. In addition, antimicrobial assays confirmed the efficacy of the films against a range of pathogens, and the 1,1-diphenyl-2-picryl hydrazyl assay indicated notable antioxidant activity, with an IC50 value of 111.45 μg/mL for the optimized formulation. These findings underscore the potential of the developed biofilms as advanced, multifunctional packaging materials, offering a promising environmentally friendly alternative to conventional packaging for food preservation.
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Synthesis, structural characterization, in vitro biological evaluation and in silico molecular docking of some new 1,2,3-Benzotriazole-based Schiff base derivatives
(Elsevier B.V, 2025-04-09) Shawkat Hayat; Mohamed S. Othman; Hayat Ullah; Amina Qureshi; Fazal Rahim; Sadiqa Begum; Mohsan Nawaz; Abdul Wadood; Amal H. Al-Bagawi; Ahmed M. Aref; Mohamed A. Fareid; Rashid Iqbal
1,2,3-benzotriazole-based Schiff base derivatives were synthesized, characterized through different techniques such as 1 HNMR, 13CNMR, and HREI-MS, and screened against the alpha-glucosidase enzyme. All the synthesized analogues showed good inhibitory potentials with IC50 values ranging from 2.20 ± 0.30 μM to 24.40 ± 0.10 μM as compared to the standard drug acarbose (IC50 = 10.30 ± 0.20 μM). The most potent analogues among the series are 3 (IC50 = 4.30 ± 0.20 μM), 8 (IC50 = 9.40 ± 0.10), 9 (IC50 = 6.20 ± 0.40), 10 (IC50 = 6.60 ± 0.20), 11 (IC50 = 6.10 ± 0.30), 12 (IC50 = 4.70 ± 0.50 μM), 13 (IC50 = 2.20 ± 0.30 μM), 14 (IC50 = 4.30 ± 0.20 μM), and 16 (IC50 = 7.40 ± 0.20), which were found manyfold more active than the standard drug acarbose. A structureactivity relationship study was established that significantly depends on the position, nature, number, and electron-donating/withdrawing effect of the substituent(s) attached to the phenyl ring. We conducted molecular docking studies to investigate the binding interaction of the most potent analogues with the active site of an enzyme.