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result(s) for
"Marwa El Sayed"
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Silver Nanoparticles Loaded on Chitosan-g-PVA Hydrogel for the Wound-Healing Applications
by
Alawam, Khaled
,
El Sayed, Marwa
,
Alduraywish, Shatha
in
Analysis
,
Animals
,
Anti-Bacterial Agents - pharmacology
2023
Silver nanoparticle composites have abundant biomedical applications due to their unique antibacterial properties. In the current work, green tea leaf extract was used as a natural reducing agent to synthesize AgNPs (AgNPs) using microwave irradiation technology. Furthermore, microwave irradiation has been used for the preparation of AgNPs/chitosan (Ch) grafted polyvinyl alcohol (PVA) hydrogel samples. To approve the accomplishment of AgNPs hydrogel polymer, UV-spectrum, TEM, and FT-IR spectrum analyses and the release of silver ions, actions were taken. The wound-healing ability of the prepared hydrogel samples was measured via both the in vitro (fibroblast cells) and the in vivo using rat models. It was found that chitosan-grafted polyvinyl alcohol, including AgNPs, exhibited excellent antibacterial activity against E. coli and S. aureus using the agar diffusion method. It can be said that microwave irradiation was successful in creating a hydrogel that contained silver nanoparticles. A wound that was still open was successfully treated with these composites.
Journal Article
Green Synthesis of Silver Nanoparticles Loaded Hydrogel for Wound Healing; Systematic Review
by
Fagir, Mohammed H.
,
El Dein, Dalia K.
,
Aldakheel, Fahad M.
in
Antibiotics
,
Antimicrobial agents
,
Bacteria
2023
Wound healing is a biological process that involves a series of consecutive process, and its impairment can lead to chronic wounds and various complications. Recently, there has been a growing interest in employing nanotechnology to enhance wound healing. Silver nanoparticles (AgNPs) have expanded significant attention due to their wide range of applications in the medical field. The advantages of AgNPs include their easy synthesis, change their shape, and high surface area. Silver nanoparticles are very efficient for topical drug administration and wound healing because of their high ratio of surface area to volume. The efficiency of AgNPs depends on the synthesis method and the intended application. Green synthesis methods offer an eco-friendly approach by utilizing natural sources such as plant extracts and fungus. The characterization of nanoparticles plays an important character, and it is accomplished through the use of several characterization methods such as UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). These techniques are employed to confirm the specific characters of the prepared Silver Nanoparticles. Additionally, the review addresses the challenges and future perspectives of utilizing green-synthesized AgNPs loaded in Polyacrylamide hydrogel for wound healing applications, including the optimization of nanoparticle size, and release kinetics. Overall, this review highlights the potential of green-synthesized AgNPs loaded in Polyacrylamide hydrogel as promising for advanced wound healing therapies. There are different approaches of usage of AgNPs for wound healing such as polyacrylamide -hydrogels, and the mechanism after their antibacterial action, have been exposed.
Journal Article
Production of Polymer Hydrogel Composites and Their Applications
2023
Hydrogels are three-dimensional cross-linked stable network insoluble in water, which gives them a remarkable capacity to absorb both water and biological fluids. Hydrogel has been synthesized from natural or synthetic polymers and/or monomers, which have made tremendous advancements in many different applications. Composite hydrogel is a type of hydrogel prepared by grafting hydrophilic groups, such as hydroxyl (–OH), carboxylic acid (–COOH), imide (–CONH), sulfonic acid (–SO3H), amine (–NH2), and amide (–CONH2), into the polymer chain’s backbone and adding some additives such as kaolin, zeolite, or even different types of nanoparticles. Whereas the polymeric composite hydrogels exhibit stimuli for different properties such as pH, temperature, or light, which may affect swelling, mechanical properties, and self-healing, which in turn play vital roles in different areas. Hence, numerous efforts have been made to synthesize polymer-based composited hydrogels via physical or chemical crosslinking techniques to enhance their physiochemical, biological, and many other properties. Many researchers are currently paying attention to hydrogels and their applications, including wastewater treatment and purification, medical and biomedical applications, agricultural applications, and many other industrial applications. The aim of this review is to summarize the classification of composite hydrogels based on their chemical and physical crosslinking techniques, in addition to the different polymers and additives used to prepare composite hydrogels. Furthermore, the impact of hydrogel on health and the environment has been discussed. Other significant issues were also presented, including the challenges that face hydrogel production and application, which have been discussed.
Journal Article
PI3K/AKT signaling activation by roflumilast ameliorates rotenone-induced Parkinson’s disease in rats
by
Sayed, Rabab H.
,
El Sayed, Nesrine S.
,
Farid, Heba A.
in
Allergology
,
Aminopyridines
,
Animals
2024
Parkinson’s disease (PD) is the second most common progressive age-related neurodegenerative disorder. Paramount evidence shed light on the role of PI3K/AKT signaling activation in the treatment of neurodegenerative disorders. PI3K/AKT signaling can be activated via cAMP-dependent pathways achieved by phosphodiesterase 4 (PDE4) inhibition. Roflumilast is a well-known PDE4 inhibitor that is currently used in the treatment of chronic obstructive pulmonary disease. Furthermore, roflumilast has been proposed as a favorable candidate for the treatment of neurological disorders. The current study aimed to unravel the neuroprotective role of roflumilast in the rotenone model of PD in rats. Ninety male rats were allocated into six groups as follows: control, rotenone (1.5 mg/kg/48 h, s.c.), L-dopa (22.5 mg/kg, p.o), and roflumilast (0.2, 0.4 or 0.8 mg/kg, p.o). All treatments were administrated for 21 days 1 h after rotenone injection. Rats treated with roflumilast showed an improvement in motor activity and coordination as well as preservation of dopaminergic neurons in the striatum. Moreover, roflumilast increased cAMP level and activated the PI3K/AKT axis via stimulation of CREB/BDNF/TrkB and SIRT1/PTP1B/IGF1 signaling cascades. Roflumilast also caused an upsurge in mTOR and Nrf2, halted GSK-3β and NF-ĸB, and suppressed FoxO1 and caspase-3. Our study revealed that roflumilast exerted neuroprotective effects in rotenone-induced neurotoxicity in rats. These neuroprotective effects were mediated via the crosstalk between CREB/BDNF/TrkB and SIRT1/PTP1B/IGF1 signaling pathways which activates PI3K/AKT trajectory. Therefore, PDE4 inhibition is likely to offer a reliable persuasive avenue in curing PD via PI3K/AKT signaling activation.
Graphical Abstract
Journal Article
Microwave-assisted synthesis and characterization of Xanthan gum-grafted polyacrylamide hydrogel for the removal of acid red 8 dye from aqueous solutions
by
Fadl, Eman Aly
,
Hamza, Marwa El-Sayed
,
El Demerdash, Abdel Ghaffar
in
639/301
,
639/638
,
Acrylamide
2025
This study focuses on creating a sustainable, biodegradable, and affordable hydrogel from xanthan gum grafted polyacrylamide using a microwave-assisted synthesis method. The hydrogel is designed to remove Acid red 8 dye (AR8) from aqueous solutions using adsorption technique. Characterization was done using FTIR, SEM, and TGA analyses. Factors affecting the adsorption of AR8 dye onto the hydrogel such as grafting percent, pH, hydrogel dosage, contact time and the dye’s initial level in solution, temperature, as well as the reusability studies were investigated. The results indicated that at pH 1, the swelling ratio reached 1720% after 20 min. The maximum adsorption capacity of AR8 dye was 177 mg/g after 20 min, with no significant increase beyond 20 min. The percent of dye removal (%) increased from 84.7 to 88.6 with increasing the hydrogel dosage from 0.0063 to 0.05 g/L and there was no increase above 0.05 g/L. The percent of dye removal of AR8 increased with increasing the percentage of grafting due to rising the number of functional groups grafted on XG backbone. Also, q
e
decreased as temperature increased from 20 to 60 °C.
Journal Article
Sustainability consciousness among nursing students in Egypt: a cross-sectional study
by
Ghallab, Eman
,
Amin, Shaimaa Mohamed
,
Mohamed, Marwa Ahmed El-Sayed
in
Attitude
,
Attitudes
,
Behavior
2024
Background
Recognizing nurses as pivotal change agents and urgent preparation for the next generation is crucial for addressing sustainability issues and cultivating a sustainable healthcare system. Reports highlight gaps in the integration of sustainable development goals (SDGs) into nursing curricula, prompting the International Council of Nurses to stress the importance of sustainable development in nursing education. The extent to which nursing students are aware of sustainability issues remains to be determined. This study addresses a global and Egyptian research gap by evaluating and comparing Sustainability Consciousness (SC) levels among nursing students at three universities, providing insights into awareness, attitudes, and behaviors related to sustainability.
Methods
This descriptive comparative study was conducted across three nursing faculties within three Egyptian public universities. The target population for this study was undergraduate nursing students enrolled in these universities during the academic year 2022-2023. This study used the extended version of the Sustainability Consciousness Questionnaire (SCQ-L) to measure individuals' knowingness, attitudes, and behaviors related to the three dimensions of sustainable development: environmental, social, and economic.
Results
More than half of the nursing students across the three universities expressed unfamiliarity with the SDGs. Social media was the most common source of information across the three universities. Sohag University recorded the highest median (IQR) scores in sustainability knowingness (72.0, IQR: 70.0-81.0), attitudes (56.0, IQR: 53.0-61.5), and behavior (65.0, IQR: 60.0-69.0) across their respective dimensions, as well as in overall SC (195, IQR: 184.5-208.5). This was followed by Damanhour University, with a median score of 179.0 (IQR: 124.5-194), and then Alexandria University, with a median score of 116.0 (IQR: 85.5-153), all of which were significantly different (all with p values=0.000). Older students from rural areas exhibited higher SC median scores, while students with insufficient family income and no familiarity with the SDGs had lower SC scores.
Conclusions
This study highlighted the prevalent reliance on social media for information among nursing students across these universities, emphasizing the pivotal role of academic institutions in integrating sustainability development concepts in nursing education. Sohag University's notable commitment to sustainability practices has contributed to the higher SC of its students compared to Alexandria and Damanhour Universities. The study also identified age, place of residence, family income, and familiarity with the SDGs as consistent predictors of sustainability consciousness.
Journal Article
The effect of recess number and conical shape on hydrostatic bearing power losses
by
El-Sayed, Marwa M.
,
Ibrahim, Masoud
,
Taleb, Ahmed. S. A. Abou
in
639/166
,
639/4077
,
ANSYS CFD
2025
Axial loads on machinery are commonly carried by hydrostatic thrust bearings. To ensure sustained performance, designers need to balance the requirement for efficient pumping power with the high load-carrying capacity. This requirement is a common challenge. For the purpose of studying the pumping power losses of hydrostatic thrust bearings, this research presents a numerical analysis of the recess shape design effect. The ANSYS workbench software has been used to implement the numerical simulation. Rectangular and circular pockets with two and four recesses are analyzed for power losses and film thicknesses using FVM and the Navier–Stokes equations. Study results indicated that the number and shape of recesses had a significant effect on power losses.
Journal Article
Enhancing the Toxicity of Cypermethrin and Spinosad against Spodoptera littoralis (Lepidoptera: Noctuidae) by Inhibition of Detoxification Enzymes
by
Ahmed A. A. Aioub
,
Mohamed M. A. Ibrahim
,
Marwa H. El-Sayed
in
Agrochemicals
,
Bioassays
,
Biopesticides
2023
The extensive use of wide-ranging insecticides in agricultural activities may develop resistance in insects. The dipping technique was utilized for examining changes in detoxifying enzyme levels in Spodoptera littoralis L. induced by cypermethrin (CYP) and spinosad (SPD) with and without a combination of three enzyme inhibitors: triphenyl phosphate (TPP), diethyl maleate (DEM), and piperonyl butoxide (PBO), at 70 μg/mL. PBO, DEM, and TPP showed 50% mortality against larvae at 236.2, 324.5, and 245.8 μg/mL, respectively. The LC50 value of CYP on S. littoralis larvae reduced from 2.86 μg/mL to 1.58, 2.26, and 1.96 μg/mL, while the LC50 value of SPD declined from 3.27 μg/mL to 2.34, 2.56, and 2.53, with the addition of PBO, DEM, and TPP, respectively, 24 h after treatment. Moreover, the activity of carboxylesterase (CarE), glutathione S-transferase (GST), and cytochrome P450 monooxygenase (Cyp 450) was significantly inhibited (p < 0.05) by TPP, DEM, PBO plus CYP, and SPD in S. littoralis larvae in comparison with tested insecticides alone. These findings suggested that three enzyme inhibitors play a major role in increasing the toxicity of CYP and SPD in S. littoralis and will provide insight into how to overcome insecticide resistance in insects.
Journal Article
The effects of isoprene and NOx on secondary organic aerosols formed through reversible and irreversible uptake to aerosol water
by
Ortiz-Montalvo, Diana L
,
Hennigan, Christopher J
,
El-Sayed, Marwa M H
in
Aerosols
,
Anthropogenic factors
,
Atmosphere
2018
Isoprene oxidation produces water-soluble organic gases capable of partitioning to aerosol liquid water. The formation of secondary organic aerosols through such aqueous pathways (aqSOA) can take place either reversibly or irreversibly; however, the split between these fractions in the atmosphere is highly uncertain. The aim of this study was to characterize the reversibility of aqSOA formed from isoprene at a location in the eastern United States under substantial influence from both anthropogenic and biogenic emissions. The reversible and irreversible uptake of water-soluble organic gases to aerosol water was characterized in Baltimore, Maryland, USA, using measurements of particulate water-soluble organic carbon (WSOCp) in alternating dry and ambient configurations. WSOCp evaporation with drying was observed systematically throughout the late spring and summer, indicating reversible aqSOA formation during these times. We show through time lag analyses that WSOCp concentrations, including the WSOCp that evaporates with drying, peak 6 to 11 h after isoprene concentrations, with maxima at a time lag of 9 h. The absolute reversible aqSOA concentrations, as well as the relative amount of reversible aqSOA, increased with decreasing NOx ∕ isoprene ratios, suggesting that isoprene epoxydiol (IEPOX) or other low-NOx oxidation products may be responsible for these effects. The observed relationships with NOx and isoprene suggest that this process occurs widely in the atmosphere, and is likely more important in other locations characterized by higher isoprene and/or lower NOx levels. This work underscores the importance of accounting for both reversible and irreversible uptake of isoprene oxidation products to aqueous particles.
Journal Article
Computational fluid dynamics analysis to improve hydrostatic thrust bearings: number of pockets and shape configuration analysis
by
Elhabak, Aiea A.
,
El-Sayed, Marwa M.
,
Ibrahim, Masoud
in
Civil Engineering
,
Computational fluid dynamics
,
Conical shapes
2025
Hydrostatic bearings are expected to attract significant attention in the coming years due to their wide use in engineering applications, such as high-speed machine tool spindles, fast-moving machinery, and precision grinding tools. However, there is still a need to better understand the flow behavior related to different pressure pocket patterns. The aim of this research is to investigate how the supplied pressure and the shape of the pocket affect the pressure distribution in hydrostatic bearings with rectangular pads. Using the 3D Navier–Stokes equations and the finite volume method in ANSYS-CFD-19 R3, different recess designs — specifically rectangular and circular recesses — were analyzed to determine their impact on static pressure. The results showed that conical-shaped recesses produced higher pressure values compared to non-conical shapes. This study focused on two main types of recess shapes: rectangular and circular.
Journal Article