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"Khalil, I"
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HPV upregulates MARCHF8 ubiquitin ligase and inhibits apoptosis by degrading the death receptors in head and neck cancer
The membrane-associated RING-CH-type finger ubiquitin ligase MARCHF8 is a human homolog of the viral ubiquitin ligases Kaposi’s sarcoma herpesvirus K3 and K5 that promote host immune evasion. Previous studies have shown that MARCHF8 ubiquitinates several immune receptors, such as the major histocompatibility complex II and CD86. While human papillomavirus (HPV) does not encode any ubiquitin ligase, the viral oncoproteins E6 and E7 are known to regulate host ubiquitin ligases. Here, we report that MARCHF8 expression is upregulated in HPV-positive head and neck cancer (HNC) patients but not in HPV-negative HNC patients compared to normal individuals. The MARCHF8 promoter is highly activated by HPV oncoprotein E6-induced MYC/MAX transcriptional activation. The knockdown of MARCHF8 expression in human HPV-positive HNC cells restores cell surface expression of the tumor necrosis factor receptor superfamily (TNFRSF) death receptors, FAS, TRAIL-R1, and TRAIL-R2, and enhances apoptosis. MARCHF8 protein directly interacts with and ubiquitinates the TNFRSF death receptors. Further, MARCHF8 knockout in mouse oral cancer cells expressing HPV16 E6 and E7 augments cancer cell apoptosis and suppresses tumor growth in vivo. Our findings suggest that HPV inhibits host cell apoptosis by upregulating MARCHF8 and degrading TNFRSF death receptors in HPV-positive HNC cells.
Journal Article
Molecular assessment of drug-phospholipid interactions consequent to cancer treatment: a study of anthracycline-induced cardiotoxicity
Cardiotoxicity limits the use of anthracyclines as potent chemotherapeutics. We employ classical molecular dynamics to explore anthracycline interactions with a realistic myocardial membrane and compare to an ideal membrane widely used in literature. The interaction of these two membranes with four anthracyclines; doxorubicin, epirubicin, daunorubicin, and idarubicin are studied. Careful analysis was conducted on three forms of each drug; pristine, primary metabolite, and cationic salt. By examining the molecular residence time near the membrane’s surface, the average number of molecule/membrane hydrogen bonds, the immobilization of the molecules near the membrane, and the location of those molecules relative to the mid-plane of the membrane we found out that salt forms exhibit the highest cardiotoxic probability, followed by the metabolites and pristine forms. Additionally, all forms have more affinity to the upper layer of the realistic myocardial membrane. Meanwhile, an ideal membrane consisting of a single type of phospholipids is not capable of capturing the specific interactions of each drug form. These findings confirm that cardiotoxic mechanisms are membrane-layer and drug-form dependent.
Journal Article
Synthesis, Characterization, and Antibacterial Activity of Mg-Doped CuO Nanoparticles
This study aims to investigate the effect of magnesium (Mg) doping on the characteristics and antibacterial properties of copper oxide (CuO) nanoparticles (NPs). The Mg-doped CuO NPs were fabricated by the co-precipitation method. NPs were characterized by X-ray Powder Diffraction (XRD), Transmission Electron Microscope (TEM), Energy Dispersive X-ray (EDX) analysis, Fourier Transform Infrared Spectroscopy (FTIR), and Photoluminescence (PL). Broth microdilution, agar-well diffusion, and time-kill assays were employed to assess the antibacterial activity of the NPs. XRD revealed the monoclinic structure of CuO NPs and the successful incorporation of Mg dopant to the Cu1−xMgxO NPs. TEM revealed the spherical shape of the CuO NPs. Mg doping affected the morphology of NPs and decreased their agglomeration. EDX patterns confirmed the high purity of the undoped and Mg-doped CuO NPs. FTIR analysis revealed the shifts in the Cu–O bond induced by the Mg dopant. The position, width, and intensity of the PL bands were affected as a result of Mg doping, which is an indication of vacancies. Both undoped and doped CuO NPs exhibited significant antibacterial capacities. NPs inhibited the growth of Gram-positive and Gram-negative bacteria. These results highlight the potential use of Mg-doped CuO NPs as an antibacterial agent.
Journal Article
Composition engineered GNS/CNT Hybrid nanocomposites with enhanced thermal stability and tunable optical properties via one-step methane CVD
Graphene nanosheet/carbon nanotube (GNS/CNT) hybrid nanocomposites were produced using a one-step methane CVD method, employing a Mo–Mg–Fe catalytic system. This facilitated the concurrent growth and integration of graphitic elements. The impact of the Mo/Mg ratio on structural development, oxide chemistry, defect density, and thermal stability was examined in detail. SAED, TEM, and SEM revealed the coexistence of wrinkled graphene sheets linked with CNTs, while EDS and STEM showed even C, O, Mg, Mo, and Fe distribution. Raman indicated low defects (I
D
/I
G
≈ 0.14), I
2D
/I
G
= 0.33, and A
2D
/A
G
≈ 0.43, which reveals that samples have common characteristics of few to multilayer graphene structures. FTIR reflected Mo/Mg-dependent oxide and surface chemistry, and UV–Vis revealed broad, enhanced optical absorption. TGA conducted in an inert atmosphere demonstrated remarkable enhanced thermal stability, characterized by negligible mass loss (2–6%) up to 1000 °C; this stability is ascribed to the formation of Mo-assisted carbides and the mitigation of Mg volatilization. The CVD method creates hybrids that are structurally low in defects. These hybrids show improved thermal stability and allow for the adjustment of their physical and chemical properties. As a result, these findings confirm that changing the catalyst’s composition is a useful way to design carbon nanohybrids with multiple functions.
Journal Article
Calibration-free picosecond LIPS for quantifying heavy metals in soils near Egyptian industrial sites
Excessive fertilizer and chemical usage have led to soil contamination by toxic heavy metals near the Abu-Zaabal industrial complex in Egypt. We introduce a groundbreaking calibration-free methodology using ultrafast Picosecond Laser-Induced Plasma Spectroscopy (CF-Ps-LIPS) for quantifying contaminant elements (Cd, Zn, Fe, Ni) in soils near Egypt’s Abu-Zaabal industrial complex. This study pioneers applying 170 ps laser pulses (Nd: YAG, 1064 nm) to achieve calibration-free analysis, eliminating matrix-matched standards and offering ± 1% agreement with ICP-OES. By integrating plasma diagnostics (electron density N
e
= 1.2–1.5 × 10
17
cm
− 3
and temperature T
e
= 8508–10,275 K), we establish CF-Ps-LIPS as a rapid, minimally invasive tool for on-site environmental monitoring, validated through spatial contamination gradients linked to wind patterns. Concentrations of Cd (25.1–136.5 mg/kg), Zn (19.8–146.9 mg/kg), Fe (59.7–62 mg/kg), and Ni (119.4–157.8 mg/kg) were analyzed across seven sampling sites. The seventh site was used as a test sample of unknown concentration to validate CF-Ps-LIPS. Utilizing the Boltzmann distribution with plotting techniques enables precise plasma electron density and temperature determination under local thermodynamic equilibrium (LTE) conditions. The CF-Ps-LIPS study revealed significant concentration variations dependent on trace metal type, sampling location, and facility orientation. The CF-Ps-LIPS method provides calibration-free, rapid, and accurate detection of metal contaminants in Egyptian soils for the first time. This methodology significantly advances environmental monitoring and soil contamination analysis, allowing on-site assessments with higher efficiency and reliability.
Journal Article
Petrogenesis of contrasting magmatic suites in the Abu Kharif area, Northern Eastern Desert, Egypt: implications for Pan-African crustal evolution and tungsten mineralization
The Abu Kharif area in the Northern Eastern Desert consists of contrasting granitic magma suites: a Cryogenian granodiorite suite (850–635 Ma), an Ediacaran monzogranite suite (635–541 Ma) and a Cambrian alkali riebeckite granite suite (541–485 Ma). Tungsten mineralization occurs within W-bearing quartz veins and a disseminated type confined to the monzogranite. Whole-rock geochemical data classify the granodiorite as a late-orogenic I-type with calc-alkaline affinity, while the monzogranite and alkali riebeckite granite represent respectively a post-orogenic highly fractionated I-type with calc-alkaline affinity and an anorogenic A1-subtype with alkaline affinity. Geochemical modelling indicates that the three intrusions represent separate magmatic pulses where the granodiorite was generated by ∼75 % batch partial melting of an amphibolitic source followed by fractional crystallization of hornblende, biotite, apatite and titanite. The monzogranite was formed by 62 % batch partial melting of the normal ‘non-metasomatized’ Pan-African crust of calc-alkaline granite composition followed by fractional crystallization of plagioclase, biotite, K-feldspar, magnetite, ilmenite, with minor apatite and titanite. The alkali riebeckite granite was generated by 65 % batch partial melting of metasomatized Pan-African granite source followed by fractional crystallization of plagioclase, K-feldspar, amphibole and biotite with minor magnetite, apatite and titanite. In general, the parent magmas of the three intrusions were originally enriched in W, but with different concentrations. This W-enrichment would be caused by magmatic-related hydrothermal volatile-rich fluids and concentrated within the monzogranite.
Journal Article
Octaarginine-modified multifunctional envelope-type nanoparticles for gene delivery
This study describes a multifunctional envelope-type nano device (MEND) that mimics an envelope-type virus based on a novel packaging strategy. MEND particles contain a DNA core packaged into a lipid envelope modified with an octaarginine peptide. The peptide mediates internalization via macropinocytosis, which avoids lysosomal degradation. MEND-mediated transfection of a luciferase expression plasmid achieved comparable efficiency to adenovirus-mediated transfection, with lower associated cytotoxicity. Furthermore, topical application of MEND particles containing constitutively active bone morphogenetic protein (BMP) type IA receptor (ca
Bmpr1a
) gene had a significant impact on hair growth
in vivo
. These data demonstrate that MEND is a promising non-viral gene delivery system that may provide superior results to existing non-viral gene delivery technologies.
Journal Article
The bio-adsorptive treatment of detergent: performance and mechanisms
This study develops an optimized hybrid system to treat sodium dodecyl sulfate (SDS)-contaminated wastewater that synergistically integrates microbial biodegradation with physical adsorption within a Response Surface Methodology (RSM) framework. A highly effective SDS-degrading bacterium,
Serratia plymuthica
strain BSU-AH-03, was isolated from hydrocarbon-contaminated soil. Using a Box-Behnken Design (BBD), the optimal biodegradation conditions (pH 7.9, 20 °C, 300 mg L⁻¹ SDS) yielded a degradation efficiency of 90.46% (predicted 91.27%, R² = 0.981). Subsequently, natural anthracite coal was employed as an adsorbent to polish the effluent. The anthracite exhibited a high surface area (890.9 m² g⁻¹) and a heterogeneous micro-mesoporous structure. Batch adsorption experiments achieved a maximum SDS uptake capacity of 158.7 mg g⁻¹ and a near-complete removal efficiency of 99.58% at 318 K and pH 7. The adsorption process was endothermic (ΔH° = 58.4 kJ mol⁻¹), spontaneous (ΔG° from – 5.15 to -10.65 kJ mol⁻¹), and followed pseudo-second-order kinetics and the Langmuir isotherm, indicating chemisorption as the dominant mechanism. Mechanistic analysis revealed that SDS adsorption involves intra-particle pore diffusion, hydrophobic interactions, electrostatic forces, and hydrogen bonding, culminating in interfacial hemi-micellar aggregation. The synergistic combination of tailored biodegradation and advanced adsorption provides a highly efficient, statistically optimized strategy for the complete remediation of surfactant-laden industrial effluents.
Journal Article
Strength of Fiber Reinforced Modified Metakaolin‐Based Geopolymer Incorporating Crumbed Rubber and Mixed Plastic Waste Aggregate Under Sulfate Solution
Rising demand for sustainable construction materials, combined with the growing knowledge about geopolymers as a green substitute for ordinary Portland cement (OPC), which has an internationally well‐known high CO 2 footprint during manufacture, has increased research into this area. Specifically, this study is intended to investigate the behavior of metakaolin‐based geopolymer concrete (GPC) modified with 5% by weight of calcium oxide and silica fume after being immersed in a solution of 5% sodium sulfate (Na 2 SO 4 ). The parameters of the mix design included metakaolin, fine and coarse aggregates, superplasticizer, and water activated with sodium hydroxide and sodium silicate solutions in proportional quantities (372, 910, 603, 8, 56, 83, and 192 kg/m 3 , respectively). To make this further impactful towards sustainability, 10% of the voluminous natural coarse aggregate was replaced with recycled mixed plastic‐waste or crumb rubber from used tires. Increasing the volume fraction of carbon fiber (0%, 0.15%, and 0.2%) to enhance its mechanical properties. This study examined the compressive strength and mass change, as well as visual assessment after exposure to sulfate solution for periods of 28, 90, 180, 366, and 456 days. After 90 days of sulfate exposure, compressive strength improvements were seen, ranging from 3% in the reference mix to 9% with plastic‐waste aggregate and 0.2% carbon fibers in the GPC‐based matrix. Although strength gradually reduced over time, after 456 days, the maximum loss was only about 22% in mixes with crumb rubber aggregate and carbon fibers, with remaining strength still acceptable. No significant surface degradation or cracking occurred, and the addition of carbon fibers enhanced both the microstructure density and compressive strength. A fiber‐reinforced metakaolin‐based GPC, which incorporates recycled aggregates, has been shown to maintain structural performance while also improving resistance to sulfate attack, suggesting it is a viable environmentally friendly alternative.
Journal Article