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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Pseudocitrobacter cyperus, a novel bacterial species recovered from Cyperus alternifolius in Egypt
(BioMed Central Ltd, 2025-01-12) Samira M. Hamed; Mai A. Amer
Background Strain Cyp38ST was isolated as an endophyte from the plant Cyperus alternifolius, collected along the banks of the River Nile in 2019. Preliminary analysis tentatively identified Cyp38ST as belonging to the genus Pseudocitrobacter. Methods The preliminary identification of Cyp38ST was performed using the VITEK®2 identification system, MALDITOF-MS, and 16S rRNA gene sequencing. To confirm its taxonomic classification, the draft genome of Cyp38ST was generated using DNBseq, and the genome-based taxonomic evaluation was conducted by calculating the overall genome-relatedness indices (OGRIs) such as Average Nucleotide Identity (ANI), digital DNA-DNA hybridization (dDDH), and the tetra-nucleotide signatures (Tetra). Additionally, the biochemical features, antimicrobial susceptibility profiles, and fatty acid methyl ester content of Cyp38ST were characterized. Results VITEK®2 misidentified Cyp38ST as Citrobacter werkmanii, MALDI-TOF-MS identified it as Pseudocitrobacter faecalis. While the 16S rRNA gene showed more than 99.0% similarity to other Pseudocitrobacter species, the calculated OGRIs were lower than the thresholds recommended for species assignment to all currently known Pseudocitrobacter species. Furthermore, the phylogenomic analysis revealed that Cyp38ST forms a distinct species cluster within the genus Pseudocitrobacter. Cyp38ST was predicted as a potential human pathogen and carried a unique ß-lactamase-coding gene. Conclusion Here we present Cyp38ST (=CCASU-2024-73T ) as the type strain of a novel species within the genus Pseudocitrobacter to which we propose the name Pseudocitrobacter cyperus sp. nov. We provide a full description of the novel species and present its genome sequence and annotation. The discovery of this novel species highlights the potential of endophytic bacteria associated with unique plant hosts to harbor previously uncharacterized microbial diversity
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Cobalt oxide nanoparticles induce cytotoxicity and excessive ROS mediated mitochondrial dysfunction and p53-independent apoptosis in melanoma cells
(Nature Publishing Group, 2025-01-06) Hanan R. H. Mohamed; Basma A. Mohamed; George M. Hakeem; Shahd H. Elnawasani; Maria Nagy; Rawan Essam; Ayman Diab; Gehan Safwat
Nanotherapy has emerged as a promising strategy for the targeted and efficient treatment of melanoma, the most aggressive and lethal form of skin cancer, with minimized systemic toxicity. However, the therapeutic efficacy of cobalt oxide nanoparticles (Co3O4NPs) in melanoma treatment remains unexplored. This study aimed to assess the therapeutic potential of Co3O4NPs in melanoma treatment by evaluating their impact on cell viability, genomic DNA and mitochondrial integrity, reactive oxygen species (ROS) generation and apoptosis induction in melanoma A-375 cells. Our findings demonstrated a concentration-dependent reduction in cell viability upon treatment with five Co3O4NP concentrations (0.2, 2, 20, 200, and 2000 µg/ml), with an IC50 value of 303.80 µg/ml. Treatment with this IC50 concentration significantly increased ROS generation, induced dramatic DNA damage, and disrupted mitochondrial membrane potential integrity. Flow cytometric analysis revealed apoptosis and necrosis induction following Co3O4NP exposure at the IC50 concentration value. Results of qRT-PCR analysis demonstrated remarkable dysregulation of apoptotic and mitochondrial genes, including a significant downregulation of apoptotic p53 and mitochondrial ND3 genes and marked upregulation of the anti-apoptotic gene Bcl2. These findings highlight the novel potential of Co3O4NPs as potent inducers of melanoma A-375 cell death in a concentration-dependent manner through excessive ROS production, genomic instability, mitochondrial dysfunction and dysregulation of apoptotic and mitochondrial gene expression, ultimately promoting apoptosis in A-375 cells. This study thus underscores the potential of Co3O4NPs as a promising nanotherapeutic candidate for melanoma treatment, warranting further exploration to elucidate their full biological and clinical applicability.
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Novel strategies for valorizing red araça pomace: Cyanidin-rich extracts recovery and sustainable bioenergy production
(Institution of Chemical Engineers, 2025-01-14) Cassamo U. Mussagy; Henua U. Hucke; Fabiane O. Farias; Julia Tretin; Leonardo M. de Souza Mesquita; Mauricio A. Rostagno; Jérémy Valette; Mushtaq Ahmad; Ahmad Mustafa; Vijaya Raghavan; Diakaridia Sangaré
This study investigates the valorization of red araçá pomace (RAP) from Easter Island (Rapa Nui) for extracting cyanidin-rich antioxidants and generating bioenergy. Using a UHPLC-PDA system, we characterized the extractable pigments, optimizing extraction conditions with bio-based solvents to achieve a maximum yield of 2.70 mg/L of cyanidin-3-O-glucoside, which constituted approximately 98 % of the extract. The antioxidant activity was evaluated using the DPPH and FRAP assay, revealing a strong antioxidant capacity. Additionally, pyrolysis of the residual colorless biomass indicated significant energy recovery potential, with thermodynamic analysis showing an energy difference of less than 4.67 kJ/mol between activation energy and enthalpy. This pioneering research highlights the dual benefits of utilizing RAP for health-promoting compounds while addressing waste management through sustainable bioenergy solutions.
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Enhanced energy storage with TiO2/NiO/ZnO core-shell heterostructures in hybrid battery-supercapacitor applications
(Elsevier B.V., 2025-01-07) Muhammad Zia Ullah Shah; Jing Feng; Farhat BiBi; Muhammad Sajjad; Muhammad Tauseef Qureshi; A.Shah; Muhammad Sanaullah Shah; Azza Mohamed Khaled; Marwa Syed Salem
We reported the synthesis of novel TiO2/NiO/ZnO ternary core-shell arrays (TCSA) by a one-pot electrospinning method via an ex-situ wet-chemical assisted route for battery-supercapacitor hybrid systems (BSCHs). The structural examinations revealed the obtained TiO2/NiO/ZnO TCSA with high purity and crystallinity. The charge storage and capacitive properties of pure TiO2, binary TiO2/NiO, and TiO2/NiO/ZnO TCSA were examined by cyclic voltammetry, impedance spectroscopy, and discharge/charge techniques. We obtained the battery-supercapacitor hybrid charge storage with remarkable capacitive properties. Interestingly, the TiO2/ NiO/ZnO TCSA achieves a maximum capacitance of 438 F/g and the lowest charge transfer resistance, which supports faster diffusion of electrolyte ions in the host electrode than that of pure TiO2, and binary TiO2/NiO composite at the same conditions. An asymmetric battery-supercapacitor hybrid system (BSCHs) was constructed utilizing battery-type electrode materials, TiO2/NiO/ZnO TCSA as anode and capacitive-type activated carbon (AC) as cathode, represented as TiO2/NiO/ZnO||AC BSCHs). This BSCHs achieved a high energy density of 43.9 Wh/kg with 749 W/kg power density at 1 A/g current rate, and the power density outreach to 3350 W/kg with 17.68 Wh/kg energy density at higher current rates. Also, a remarkable stability was displayed with 94.9 % capacitance retention after 3000 cycles by assembling a BSCHs. The aid of an optimum voltage of 1.5 V coupled with a high capacitance of 140.6 F/g realizes the considerable energy storage performance, which can be effectively extended to construct other oxide-based low-cost electrodes for electronic devices.
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Beverage-Induced Surface Changes in Biomimetic Dental Resin Composite: AFM and Bacterial Analysis
(Georg Thieme Verlag, 2024-12-30) Rasha R. Basheer; Nermeen K. Hamza
Objective Continuous advancements in composite resin materials have revolutionized and expanded its clinical use, improving its physical and mechanical properties. Attaining and retaining surface texture and gloss are crucial for the long-term durability of the composite resin material. This study investigated the supra-nanospherical filler composite material compared with different composite resin materials immersed in different beverages. The study evaluated their surface roughness and subsequent adhesion of bacteria. Materials and methods A total of 144 specimens were made, using Teflon mold from different composite materials. Eighty-four specimens were used for surface roughness testing, using four different resin composite materials, Tetric N-Ceram (Ivoclar Vivadent, Schaan, Liechtenstein), Multichrome (Harvard Dental, Germany), Filtek Z350 XT (3M ESPE, Minnesota, United States), and Palfique LX5 (Tokuyama Dental Corporation, Taitō-Ku, Tokyo, Japan; n ¼ 21). They were further subdivided into three subgroups according to the immersion solution (n ¼ 7) for Monster, Gatorade, and deionized water, which served as the control group. Surface roughness values were tested via atomic force microscopy (AFM). Then, for biofilm testing the bacterial count was performed on the remaining 60 composite specimens from the four tested composite materials (n ¼ 15), that were subdivided randomly based on the immersion solutions into three subgroups (n ¼ 5). Statistical analysis Data were collected and statistically analyzed using the Kruskal– Wallis test followed by Dunn’s post hoc test with Bonferroni’s correction (p 0.05). The intergroup comparison showed a significant difference among different composite materials (p < 0.05), with the Multichrome showing the highest roughness values. Also, there was a significant difference between all composite materials with different beverages, with Palfique LX5 showing the lowest average roughness (Ra) values. All studied materials’ average surface roughness, however, remained below the crucial Ra value of 0.2 μm. For the bacterial count, there was a significant difference between different materials in different beverages (p < 0.05), with Z350 XT and Palfique LX5 showing the lowest bacterial count. Conclusion Supra-nanospherical composite (Palfique LX5) exhibited better resistance to different beverage challenges regarding surface roughness, while nanohybrid composite (Z350) showed the least bacterial adherence.