Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
339
result(s) for
"Khafagy"
Sort by:
On-Chip Silicon Bragg-Grating-Waveguide-Based Polymer Slot for Gas Sensing
by
Khafagy, Merna
,
Khafagy, Maira
,
Hesham, Passant
in
Bragg grating
,
Bragg gratings
,
Carbon dioxide
2025
This work presents a novel CO2 gas sensor based on a slotted polymer-phaseshift Bragg grating (SP-PSBG) waveguide filled with polyhexamethylene biguanide (PHMB) as the sensing medium. The transmission resonance, characterized by a narrow peak with a full width at half maximum (FWHM) of 1.6 nm within the Bragg grating bandgap, is highly responsive to refractive index changes in PHMB caused by variations in CO2 concentration. Numerical simulations demonstrate a sensitivity of 14.4 pm/ppm, outperforming conventional gas sensors based on functional material coatings. This enhanced performance comes from the direct interaction between the PHMB-filled resonant structure and the cladding that contains CO2 molecules, eliminating the need for polymer-coated cladding layers. The optimization approach employed in this design focuses on maximizing the optical confinement factor within the PHMB-filled slot, leading to an effective overlap between the guided optical mode and the sensing material.
Journal Article
Biofilm Lifestyle in Recurrent Urinary Tract Infections
by
Rizvi, Syed Mohd Danish
,
Khafagy, El-Sayed
,
Tabrez, Shams
in
anti-virulence agents
,
Antibiotics
,
Antimicrobial agents
2023
Urinary tract infections (UTIs) represent one of the most common infections that are frequently encountered in health care facilities. One of the main mechanisms used by bacteria that allows them to survive hostile environments is biofilm formation. Biofilms are closed bacterial communities that offer protection and safe hiding, allowing bacteria to evade host defenses and hide from the reach of antibiotics. Inside biofilm communities, bacteria show an increased rate of horizontal gene transfer and exchange of resistance and virulence genes. Additionally, bacterial communication within the biofilm allows them to orchestrate the expression of virulence genes, which further cements the infestation and increases the invasiveness of the infection. These facts stress the necessity of continuously updating our information and understanding of the etiology, pathogenesis, and eradication methods of this growing public health concern. This review seeks to understand the role of biofilm formation in recurrent urinary tact infections by outlining the mechanisms underlying biofilm formation in different uropathogens, in addition to shedding light on some biofilm eradication strategies.
Journal Article
Randomized Controlled Trial on Autologous Platelet-Rich Plasma Versus Saline Dressing in Treatment of Non-healing Diabetic Foot Ulcers
2020
Background
This randomized clinical trial was conducted to assess the role of platelet-rich plasma (PRP) gel as a treatment of clean non-healing diabetic foot ulcer (DFU) in comparison with regular dressing with saline as a control.
Methods
Patients with DFU were randomly assigned to one of two equal groups: group I received dressing with PRP gel and group II received regular saline dressing. The main outcomes of the study were percent reduction in the dimensions of the DFU, healing of DFU, and complications at 20 weeks of follow-up.
Results
Twenty-four patients were included to the study. The mean age of patients was 55.2 ± 6.4 years. Only three (25%) patients in group I achieved complete healing versus none of group II patients. In total, 8.3% of group I and 41.6% of group II patients did not show any response to treatment. The percent of reduction in the longitudinal and horizontal dimensions of the DFU was significantly greater in group I than group II (43.2% vs 4.1%) and (42.3% vs 8.2%), respectively. The time required to maximum healing was significantly shorter in group I than group II (6.3 ± 2.1 vs 10.4 ± 1.7 weeks,
P
< 0.0001).
Conclusion
The use of PRP gel as a dressing for chronic DFU resulted in a more significant reduction in the size of the ulcer when compared to regular saline dressing. Also the time to reach the point of maximal possible healing with the least wound dimensions was significantly shorter when using PRP as a dressing protocol.
Journal Article
Formulation, characterization, and cellular toxicity assessment of tamoxifen-loaded silk fibroin nanoparticles in breast cancer
by
Allam, Ahmed N.
,
Khafagy, El-Sayed
,
Moin, Afrasim
in
Antineoplastic Agents - administration & dosage
,
Antineoplastic Agents - pharmacology
,
Apoptosis
2021
Silk fibroin (SF) is a natural polymeric biomaterial that is widely adopted for the preparation of drug delivery systems. Herein, we aimed to fabricate and characterize SF nanoparticles loaded with the selective estrogen receptor modulator; tamoxifen citrate (TC-SF-NPs) and to assess their in vitro efficacy against breast cancer cell lines (MCF-7 and MDA-MB-231). TC-loaded SF-NPs were characterized for particle size, morphology, entrapment efficiency, and release profile. In addition, we examined the in vitro cytotoxicity of TC-SF-NPs against human breast cancer cell lines and evaluated the anticancer potential of TC-SF-NPs through apoptosis assay and cell cycle analysis. Drug-loaded SF-NPs showed an average particle size of 186.1 ± 5.9 nm and entrapment efficiency of 79.08%. Scanning electron microscopy (SEM) showed the nanoparticles had a spherical morphology with smooth surface. Tamoxifen release from SF-NPs exhibited a biphasic release profile with an initial burst release within the first 6 h and sustained release for 48 h. TC-SF-NPs exerted a dose-dependent cytotoxic effect against breast cancer cell lines. In addition, flow cytometry analysis revealed that cells accumulate in G
0
/G
1
phase, with a concomitant reduction of S- and G
2
-M-phase cells upon treatment with TC-SF-NPs. Consequently, the potent anticancer activities of TC-SF-NPs against breast cancer cells were mainly attributed to the induction of apoptosis and cell cycle arrest. Our results indicate that SF nanoparticles may represent an attractive nontoxic nanocarrier for the delivery of anticancer drugs.
Journal Article
Ocular Delivery of Bimatoprost-Loaded Solid Lipid Nanoparticles for Effective Management of Glaucoma
by
Khafagy, El-Sayed
,
Moin, Afrasim
,
Obaidullah, Ahmad J.
in
Bimatoprost
,
Bioavailability
,
central composite design
2023
Glaucoma is a progressive optic neuropathy characterized by a rise in the intraocular pressure (IOP) leading to optic nerve damage. Bimatoprost is a prostaglandin analogue used to reduce the elevated IOP in patients with glaucoma. The currently available dosage forms for Bimatoprost suffer from relatively low ocular bioavailability. The objective of this study was to fabricate and optimize solid lipid nanoparticles (SLNs) containing Bimatoprost for ocular administration for the management of glaucoma. Bimatoprost-loaded SLNs were fabricated by solvent evaporation/ultrasonication technique. Glyceryl Monostearate (GMS) was adopted as solid lipid and poloxamer 407 as surfactant. Optimization of SLNs was conducted by central composite design. The optimized formulation was assessed for average particle size, entrapment efficiency (%), zeta potential, surface morphology, drug release study, sterility test, isotonicity test, Hen’s egg test-chorioallantoic membrane (HET-CAM) test and histopathology studies. The optimized Bimatoprost-loaded SLNs formulation had an average size of 183.3 ± 13.3 nm, zeta potential of −9.96 ± 1.2 mV, and encapsulation efficiency percentage of 71.8 ± 1.1%. Transmission electron microscopy (TEM) study revealed the nearly smooth surface of formulated particles with a nano-scale size range. In addition, SLNs significantly sustained Bimatoprost release for up to 12 h, compared to free drug (p < 005). Most importantly, HET-CAM test nullified the irritancy of the formulation was verified its tolerability upon ocular use, as manifested by a significant reduction in mean irritation score, compared to positive control (1% sodium dodecyl sulfate; p < 0.001). Histopathology study inferred the absence of any signs of cornea tissue damage upon treatment with Bimatoprost optimized formulation. Collectively, it was concluded that SLNs might represent a viable vehicle for enhancing the corneal permeation and ocular bioavailability of Bimatoprost for the management of glaucoma.
Journal Article
Phytosomes as a Plausible Nano-Delivery System for Enhanced Oral Bioavailability and Improved Hepatoprotective Activity of Silymarin
by
Khafagy, El-Sayed
,
Moin, Afrasim
,
Shriram, Ravi Gundadka
in
Alzheimer's disease
,
anti-oxidant activity
,
Bioavailability
2022
Silymarin, a phyto-constituent derived from the plant Silybum marianum, has been widely acknowledged for its hepatoprotective activities. Nevertheless, its clinical utility is adversely hampered by its poor water-solubility and its limited oral bioavailability. The aim of this study was to investigate the efficacy of phospholipid-based phytosomes for enhancing the oral bioavailability of silymarin. The phytosomes were prepared using the solvent evaporation technique and were optimized using a full factorial design. The optimized silymarin phytosomal formulation was then characterized for particle size, surface morphology, aqueous solubility, and in vitro drug release. Furthermore, in vivo antioxidant activity, hepatoprotective activity and oral bioavailability of the optimized formula were investigated in a rat model. The prepared silymarin phytosomes were discrete particles with a porous, nearly smooth surface and were 218.4 ± 2.54 nm in diameter. In addition, the optimized silymarin phytosomal formulation showed a significant improvement in aqueous solubility (~360 µg/mL) compared to pure silymarin and manifested a higher rate and extent of silymarin release from the optimized formula in dissolution studies. The in vivo assessment studies revealed that the optimized silymarin phytosomal formulation efficiently exerted a hepatoprotective effect in a CCl4-induced hepatotoxicity rat model via restoring the normal levels of antioxidant enzymes and ameliorating cellular abnormalities caused by CCl4-intoxication. Most notably, as compared to pure silymarin, the optimized silymarin phytosomal formulation significantly improved silymarin oral bioavailability, as indicated by a 6-fold increase in the systemic bioavailability. Collectively, phytosomes might represent a plausible phospholipid-based nanocarrier for improving the oral bioavailability of phyto-constituents with poor aqueous solubility.
Journal Article
Modeling of methane emissions from waste disposal sites at selected Egyptian governorates and potential energy production from waste-to-energy projects
by
Emara, Karim
,
Mohamed Naguib Mohamed Khafagy, Shady
,
El Sammak, Amr
in
639/638/224/906/4055
,
639/638/675
,
704/106/694/682
2024
Waste and energy sectors have significant contributions to the greenhouse gas (GHG) emissions caused primarily by the population expansion. Waste-to-Energy (WtE) is introduced to address the issue raised by both sectors simultaneously through utilization of the potential energy stored in municipal solid waste (MSW) as well as offsetting GHG emissions. Limited research have been conducted in Egypt to assess the current situation of MSW management and associated methane emissions. The current study focused on estimating the baseline methane emissions for six Egyptian governorates and determining the energy production potential from WtE projects. To achieve this aim, three scenarios have been assessed: Baseline, Landfill Gas to Energy (LFGE), and Incineration scenarios. Key results revealed that a total of 3.7 million tonnes of methane would be emitted from all studied governorates generated over 50 years. Incineration also found to be more favorable in all governorates in terms of energy production, quantity of avoided GHG emissions, and in terms of economic viability over LFGE. Implementing incineration in all governorates would generate about 5.6 TWh energy annually and could avoid about 5 Mt CO
2
eq annually in comparison to LFGE that would generate about 0.6 TWh annually and could avoid about 2.5 Mt CO
2
eq annually. In terms of economic viability of WtE projects, while they were generally not economically viable under the assumptions made in the current study, incineration technology deemed promising, but policy adjustments, such as competitive Feed-in Tariff (FiT) rates and the inclusion of gate fees, are necessary. Specific minimum gate fees and FiT were identified for each governorate, providing essential guidance for decision makers to ensure the viability of WtE implementation. This study would support the decision makers in assessing technically and financially feasible options for WtE technologies in the selected governorates.
Journal Article
Women in otorhinolaryngology; their challenges and perspective: a cross-sectional study
by
Moneir, Waleed
,
Salem, Eman H.
,
Khafagy, Ahmed Y.
in
Breastfeeding & lactation
,
Careers
,
Cross-sectional studies
2024
Background
The present study investigates the representation of women in the Otolaryngology department in a tertiary academic hospital, and the challenges they face during their residencies.
Methods
A questionnaire which included demographic information and a series of 54-questions of academic, clinical, social, psychological, and private practice challenges was electronically distributed among female residents registered in the Department of Otolaryngology in the last 10 years (2013–2022) throughout November 2023 to January 2024.
Results
Eighty-one female residents out of 103 registered (78.6%) responded to the distributed questionnaire highlighting the challenges they faced during their training period.
Conclusion
The current study addresses the barriers confronted by female residents in the department as well as identifying potential solutions that might help future encouragement of women to select otolaryngology as their specialty.
Journal Article
Tailoring of Novel Bile Salt Stabilized Vesicles for Enhanced Transdermal Delivery of Simvastatin: A New Therapeutic Approach against Inflammation
by
Almutairy, Bjad
,
Abu Lila, Amr
,
Khafagy, El-Sayed
in
Analysis
,
Anti-inflammatory agents
,
Bile
2023
Simvastatin (SMV), a cholesterol-lowering agent, has antioxidant and anti-inflammatory effects. Nevertheless, the oral use of SMV is linked with poor systemic bioavailability owing to its limited aqueous solubility and extensive first-pass metabolism. The aim of this study was to evaluate the feasibility of transdermal delivery of SMV using bile salt stabilized vesicles (bilosomes) for enhancing the anti-inflammatory potential of SMV. SMV-loaded bilosomes (SMV-BS) were prepared by the thin film hydration technique and optimized by 33 Box–Behnken design. The fabricated SMV-BS were assessed for vesicle size, entrapment efficiency (% EE) and cumulative drug release. The optimized formula was incorporated into HPMC gel and investigated for physical properties, ex vivo permeation, in vivo pharmacokinetic study and anti-inflammatory potential in inflamed paw edema rat model. The optimized SMV-BS showed vesicle size of 172.1 ± 8.1 nm and % EE of 89.2 ± 1.8%. In addition, encapsulating SMV within bilosomal vesicles remarkably sustained drug release over 12 h, compared to plain drug suspension. Furthermore, SMV-loaded bilosomal gel showed a three-fold enhancement in SMV transdermal flux, compared to plain drug suspension. Most importantly, the relative bioavailability of SMV-BS gel was ~2-fold and ~3-fold higher than those of oral SMV suspension and SMV gel, respectively. In carrageenan-induced paw edema model, SMV-BS gel induced a potent anti-inflammatory effect, as evidenced by a remarkable reduction in paw edema, which was comparable to that of the standard anti-inflammatory drug, indomethacin. Collectively, bilosomes might represent a plausible transdermal drug delivery system that could enhance the anti-inflammatory activity of SMV by boosting its skin permeation and its systemic bioavailability.
Journal Article
Effect of glycerin on the physical properties of polyvinyl alcohol/sodium alginate blend
2024
Because of the abundance of sodium resources, sodium-ion batteries (NIBs) offer a promising alternative electrochemical energy storage solution. One of the current roadblocks to the development of NIBs technology is a lack of electrode materials capable of reversibly storing/releasing sodium ions for a sufficiently long time. Thus, this work aims to study, theoretically, the effect of glycerin incorporation on polyvinyl alcohol (PVA)/sodium alginate (Na Alg) blend as electrode materials for NIBs. The electronic, thermal, and quantitative structure-activity relationship (QSAR) descriptors of polymer electrolytes based on a blend of PVA and Na Alg and glycerin are the main topics of this work. These properties are examined here using semi-empirical methods and the density functional theory (DFT). Bandgap energy (E
g
) is examined because the structural analysis reveals details regarding the interactions between PVA/Na Alg and glycerin. The findings indicate that the addition of glycerin caused the E
g
value to drop to 0.2814 eV. The molecular electrostatic potential surface, or MESP, shows the electron-rich and deficit regions throughout the electrolyte system as well as the distribution of molecular charges. Thermal parameters that are studied include enthalpy (H), entropy (ΔS), heat capacity (Cp), Gibbs’ free energy (G), and heat of formation. Additionally, the study examines several QSAR descriptors, such as total dipole moment (TDM), total energy (E), ionization potential (IP), Log P, and Polarizability. The results show that H, ΔS, Cp, G, and TDM increased with increasing temperature and glycerin content. Meanwhile, heat of formation, IP, and E decreased, improving reactivity and polarizability. Additionally, the cell voltage increased to 2.488 V due to glycerin addition. The overall DFT and PM6 calculations of cost-effective PVA/Na Alg based glycerin electrolytes indicate that they can partially replace lithium-ion batteries due to their multifunctionality, but requires further improvement and investigations.
Journal Article