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"Mohamed, Tarek M."
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Biosynthesis of cellulose from Ulva lactuca, manufacture of nanocellulose and its application as antimicrobial polymer
2023
Green nanotechnology has recently been recognized as a more proper and safer tool for medical applications thanks to its natural reductions with low toxicity and avoidance of injurious chemicals. The macroalgal biomass was used for nanocellulose biosynthesis. Algae are abundant in the environment and have a high content of cellulose. In our study, we extracted parent cellulose from
Ulva lactuca
where consecutive treatments extracted cellulose to obtain an insoluble fraction rich in cellulose. The extracted cellulose has the same results obtained by matching it with reference cellulose, especially the same Fourier transform infrared (FTIR) and X-Ray diffraction (XRD) analysis peaks. Nanocellulose was synthesized from extracted cellulose with hydrolysis by sulfuric acid. Nanocellulose was examined by Scanning electron microscope (SEM) shown by a slab-like region as Fig. 4a and Energy dispersive X-ray (EDX) to examine the chemical composition. The size of nanocellulose in the range of 50 nm is calculated by XRD analysis. Antibacterial examination of nanocellulose was tested against Gram+ bacteria like
Staphylococcus aureus
(ATCC6538),
Klebsiella pneumonia
(ST627), and Gram-negative bacteria such as
Escherichia coli
(ATCC25922), and
coagulase-negative Staphylococci (CoNS)
to give 4.06, 4.66, 4.93 and 4.43 cm as respectively. Comparing the antibacterial effect of nanocellulose with some antibiotics and estimating minimal Inhibitory Concentration (MIC) of nanocellulose. We tested the influence of cellulose and nanocellulose on some fungi such as
Aspergillus flavus, Candida albicans,
and
Candida tropicalis
. These results demonstrate that nanocellulose could be developed as an excellent solution to these challenges, making nanocellulose extracted from natural algae a very important medical material that is compatible with sustainable development.
Journal Article
Synthesis of an enhanced nanobiocatalyst system from Aspergillus niger as single green source
2025
The development of sustainable nanobiocatalysts is a focal challenge in green chemistry, requiring robust and eco-friendly production methods. This study introduces a single-source strategy that addresses this challenge. By utilizing the fungus
Aspergillus niger
as a single biological factory to simultaneously produce a lipase enzyme and biosynthesize the iron oxide nanoparticles (IONPs) that serve as lipase matrix support. This integrated approach ensures a high degree of compatibility between the enzyme and its nanoparticle support, which was confirmed during the immobilization step by an 81.73% yield and a remarkable 97.4% activity retention. The resulting nanobiocatalyst demonstrated a distinct operational stability, broad pH tolerance, and maintained over 80% of its activity after eight consecutive reuse cycles. In practical applications, the catalyst showed powerful bioremediation capabilities, achieving near-complete (> 95%) removal of industrial dyes and effective oil-stain removal from fabric. Our findings could establish that using a single biological source for both the enzyme and its immobilization matrix offers a new benchmark for future enzyme immobilization technologies.
Journal Article
Quercetin mitigates rheumatoid arthritis by inhibiting adenosine deaminase in rats
by
Atta, Amira
,
El-Said, Karim Samy
,
Mohamed, Tarek M.
in
Adenosine
,
Adenosine deaminase
,
Biomedical and Life Sciences
2022
Rheumatoid arthritis (RA) is a chronic inflammatory joint disease characterized by synovial proliferation and bone destruction. Adenosine deaminase (ADA) is a key inflammatory enzyme that increases joint stiffness and pain in RA. In this study, we evaluated the in-silico, and in vivo inhibitory effect of quercetin isolated from Egyptian Fenugreek on ADA enzyme activity. We also determined the combinatorial effect of quercetin on methotrexate mediated anti-inflammatory efficacy and toxicity. In-silico molecular docking was conducted and confirmed in an in vivo RA rat model. The results showed that the inhibition constant of quercetin on joint ADA by docking and in-vitro was 61.9 and 55.5 mM, respectively. Therefore, quercetin exhibits anti-inflammatory effect in a rat RA model as evidenced by reducing the specific activity of ADA in joint tissues, lower jaw volume, enhance body weight, downregulate ADA gene expression, reduce levels of RA cytokines interleukin-1
β
, interleukin-6, tumor necrosis factor-α, also, rheumatoid factor, C-reactive protein, and anti-cyclic citrullinated peptide RA biomarker levels. These findings demonstrate that the purified quercetin has a promising anti-inflammatory effect against RA disease through its inhibitory effects on the ADA enzyme. Furthermore, isolated quercetin improved the anti-inflammatory efficacy of methotrexate, reduced its toxic effects by increasing antioxidant enzymes and reducing oxidative stress.
Journal Article
The UFM1 system regulates ER-phagy through the ufmylation of CYB5R3
2022
Protein modification by ubiquitin-like proteins (UBLs) amplifies limited genome information and regulates diverse cellular processes, including translation, autophagy and antiviral pathways. Ubiquitin-fold modifier 1 (UFM1) is a UBL covalently conjugated with intracellular proteins through ufmylation, a reaction analogous to ubiquitylation. Ufmylation is involved in processes such as endoplasmic reticulum (ER)-associated protein degradation, ribosome-associated protein quality control at the ER and ER-phagy. However, it remains unclear how ufmylation regulates such distinct ER-related functions. Here we identify a UFM1 substrate, NADH-cytochrome b5 reductase 3 (CYB5R3), that localizes on the ER membrane. Ufmylation of CYB5R3 depends on the E3 components UFL1 and UFBP1 on the ER, and converts CYB5R3 into its inactive form. Ufmylated CYB5R3 is recognized by UFBP1 through the UFM1-interacting motif, which plays an important role in the further uyfmylation of CYB5R3. Ufmylated CYB5R3 is degraded in lysosomes, which depends on the autophagy-related protein Atg7- and the autophagy-adaptor protein CDK5RAP3. Mutations of
CYB5R3
and genes involved in the UFM1 system cause hereditary developmental disorders, and ufmylation-defective
Cyb5r3
knock-in mice exhibit microcephaly. Our results indicate that CYB5R3 ufmylation induces ER-phagy, which is indispensable for brain development.
The UFM1 system, a ubiquitin-like conjugation system is crucial for endoplasmic reticulum (ER) homeostasis. Here, authors found that CYB5R3 is covalently conjugated with UFM1, which becomes a signal for ER-phagy, a selective autophagy of ER.
Journal Article
Nano Astaxanthin ameliorates myocardial infarction in rats through autophagy
2025
Acute myocardial infarction (MI), a serious manifestation of ischemic heart disease, remains the culprit for mortality among coronary heart disease patients. Astaxanthin has demonstrated the ability to alleviate inflammation-induced myocardial damage while maintaining a balance between oxidants and antioxidants. This study investigates the cardioprotective potential of astaxanthin (ASX), particularly when encapsulated in nanostructured lipid carriers (NLCs), in isoprenaline (ISO)-induced myocardial infarction in rats. The study involved 48 rats separated into 6 groups. ASX and Nano-ASX (5 mg/kg) were administrated orally for 21 days before MI induction (isoprenaline, 85 mg/kg, subcutaneously). Blood and cardiac tissue samples were taken 24 h following the last isoprenaline injection for biochemical and histopathological investigation. The findings reveal that nano-formulated ASX significantly reduces oxidative stress and cardiac injury markers, including CK-MB, Troponin-I, and LDH. Additionally, it enhances antioxidant enzyme activities (GSH, GPx, and GSH-RD) and decreases inflammatory markers (COX-2 and VEGF). The study further demonstrates that nano-ASX stimulates autophagy by upregulating critical genes such as Beclin-1, ULK1, and LC3B, which are vital for cardiac protection and repair. Histological analysis confirms these biochemical outcomes, showing reduced myocardial damage and inflammation in the nano-ASX-treated groups. This study concludes the potential of ASX nano-formulations as an advanced therapeutic approach for myocardial infarction, leveraging improved bioavailability and targeting oxidative stress, inflammation, and autophagic mechanisms.
Journal Article
Non-alcoholic fatty liver disease is associated with decreased bone mineral density in upper Egyptian patients
by
Kenawy, Eglal M.
,
Qura, Mohamed Khairy
,
Abdelmeguid, Mona Mohamed
in
692/4020
,
692/4023
,
Body mass index
2023
Nonalcoholic fatty liver disease (NAFLD) has been linked with a number of extra hepatic diseases and could be a potential risk factor of decreasing bone mineral density. To determine whether Upper Egyptian patients with NAFLD are at risk of developing osteoporosis. Cross sectional study was done on a total 100 individuals; 50 patients diagnosed with NAFLD (based on ultrasound imaging) crossed-matched with 50 individuals without NAFLD based on age, sex and body mass index. Bone mineral density, serum calcium and phosphorus levels, serum parathyroid hormone, serum vitamin D and fasting insulin level were assessed. Osteoporosis was prevalent in NAFLD patients versus to controls (19/50 vs. 0/50;
P
< 0.001). There was significant decrease in bone mineral density in NAFLD patients than controls (− 2.29 ± 0.4 vs. − 1.53 ± 0.1;
P
< 0.001). There was a statistical significance decrease in serum vitamin D and calcium levels in NAFLD patients than controls. Furthermore, vitamin D levels in the NAFLD group was a predictor for osteoporosis (OR 0.614; 95% CI 0.348–0.825). Patients with NAFLD tend to have a significant decrease in bone density, vitamin D, and serum calcium levels than controls.
Journal Article
The synthetic opioid fentanyl enhances viral replication in vitro
by
Mohamed Tarek M. Shata
,
Ling Kong
,
Jennifer L. Brown
in
Addictions
,
Analgesics, Opioid
,
Analogs
2021
The US is in the midst of a major drug epidemic fueled in large part by the widespread recreational use of synthetic opioids such as fentanyl. Persons with opioid use disorder are at significant risk for transmission of injection-associated infections such as hepatitis B virus (HBV) and hepatitis C virus (HCV). Commonly abused substances may antagonize immune responses and promote viral replication. However, the impact of synthetic opioids on virus replication has not been well explored. Thus, we evaluated the impact of fentanyl and carfentanil using in vitro systems that replicate infectious viruses. Fentanyl was used in cell lines replicating HBV or HCV at concentrations of 1 ng, 100 ng, and 10 ug. Viral protein synthesis was quantified by ELISA, while apoptosis and cell death were measured by M30 or MTT assays, respectively. HCV replicative fitness was evaluated in a luciferase-based system. RNAseq was performed to evaluate cellular gene regulation in the presence of fentanyl. Low dose fentanyl had no impact on HCV replication in Huh7.5JFH1 hepatocytes; however, higher doses significantly enhanced HCV replication. Similarly, a dose-dependent increase in HCV replicative fitness was observed in the presence of fentanyl. In the HepG2.2.15 hepatocyte cell line, fentanyl caused a dose-dependent increase in HBV replication, although only a higher doses than for HCV. Addition of fentanyl resulted in significant apoptosis in both hepatocyte cell lines. Cell death was minimal at low drug concentrations. RNAseq identified a number of hepatocyte genes that were differentially regulated by fentanyl, including those related to apoptosis, the antiviral / interferon response, chemokine signaling, and NFκB signaling. Collectively, these data suggest that synthetic opioids promote viral replication but may have distinct effects depending on the drug dose and the viral target. As higher viral loads are associated with pathogenesis and virus transmission, additional research is essential to an enhanced understanding of opioid-virus pathogenesis and for the development of new and optimized treatment strategies.
Journal Article
Synthesis, characterization and theoretical studies of nitroxoline azo dye metal complexes and their role in mitigation of rheumatoid arthritis
2025
In this work, an azo dye ligand of 2,6-dichloroaniline with nitroxoline (
CPAQ
), and its Zn(II), Cu(II), Cd(II), Ni(II) and Co(II) complexes have been synthesized. The structures of the synthesized compounds have been elucidated applying analytical and spectral tools. According to these results, all complexes proved to have a tetrahedral structure, except Ni(II) complex, which has an octahedral geometry. Analytical results also inferred the formation of Co(II) and Ni(II) complexes in the molar ratio 1M:1L and the remaining complexes in 1M:2L molar ratio. For further insight into the complexes’ geometry, bond lengths, bond angles, and electronic characteristics with respect to the organic ligand were assigned in addition to DFT calculations. HOMO and LOMO calculations show the Co(II) complex is more reactive. The interactions of the target compounds with the
Mus musculus
ADA enzyme structure (PDB ID: 1a4m) were estimated by applying molecular docking studies. The inhibitory effect of the synthesized compounds on adenosine deaminase enzyme (ADA) activity was tested in-vitro, showing the Co(II) to be the most active.
Journal Article
Harnessing exosomes for targeted drug delivery systems to combat brain cancer
by
Atta, Amira
,
Mohamed, Tarek M.
,
Basyoni, Abdullah E.
in
Apoptosis
,
Biomedical and Life Sciences
,
Biomedicine
2025
Brain cancer remains a significant challenge in the field of oncology, primarily because of its aggressive nature and the limited treatment options available. Conventional therapies often fall short in effectively targeting tumor cells, while sparing healthy brain tissue from collateral damage. However, exosomes are now recognized as promising nanocarriers for targeted drug delivery. These naturally occurring extracellular vesicles can cross the blood–brain barrier and selectively interact with cancer cells. Utilizing exosomes as drug delivery vehicles offers a novel approach with significant potential for targeted therapy. By encapsulating therapeutic agents within exosomes, drugs can be specifically targeted to tumor cells, maximizing their impact whilst minimizing damage to healthy brain tissue. Furthermore, exosomes can be modified to display molecules that specifically recognize and bind to cancer cells, further enhancing their precision and efficacy. While exosome-based therapies show potential, scalability, purification, and clinical application challenges remain. The scalability of exosome production, purification, and modification techniques remains a hurdle that must be overcome for clinical translation. Additionally, the intricate interactions between the tumor microenvironment and exosomes necessitate further research to optimize therapeutic outcomes. The review explores applications and future perspectives of exosome-based therapies in advancing targeted brain cancer treatment.
Journal Article
Mechanistic role of quercetin as inhibitor for adenosine deaminase enzyme in rheumatoid arthritis: systematic review
by
Atta, Amira
,
El-Said, Karim Samy
,
Mohamed, Tarek M.
in
Adenosine
,
Adenosine deaminase
,
Adenosine Deaminase - metabolism
2024
Rheumatoid arthritis (RA) is an autoimmune disease involving T and B lymphocytes. Autoantibodies contribute to joint deterioration and worsening symptoms. Adenosine deaminase (ADA), an enzyme in purine metabolism, influences adenosine levels and joint inflammation. Inhibiting ADA could impact RA progression. Intracellular ATP breakdown generates adenosine, which increases in hypoxic and inflammatory conditions. Lymphocytes with ADA play a role in RA. Inhibiting lymphocytic ADA activity has an immune-regulatory effect. Synovial fluid levels of ADA are closely associated with the disease’s systemic activity, making it a useful parameter for evaluating joint inflammation. Flavonoids, such as quercetin (QUE), are natural substances that can inhibit ADA activity. QUE demonstrates immune-regulatory effects and restores T-cell homeostasis, making it a promising candidate for RA therapy. In this review, we will explore the impact of QUE in suppressing ADA and reducing produced the inflammation in RA, including preclinical investigations and clinical trials.
Graphical Abstract
Journal Article