Using a pulsed laser ablation system, core–shell [email protected] nanoparticles ([email protected] NPs) were efficiently synthesized and incorporated into a polymeric nanofibrous cellulose acetate (CA)/polyvinylidene fluoride (PVDF) solution prior to electrospinning. Highly crystalline [email protected] NPs were formed in a spherical core/shell configuration with core and shell diameters of 10.5 nm and 25 nm, respectively. The networked scaffolds were decorated with micro-distensions with lengths ranging from 2.8 to 4.3 μm at the lowest [email protected] NPs content. Cell viability analysis confirmed the high biocompatibility of the produced scaffolds, with survival ratios around 91.1 ± 3.4% and 88.2 ± 4.3% at the lowest and highest concentrations of [email protected] NPs, respectively. Obviously, the cells spread and proliferated significantly through the nanofibers. Moreover, the cells not only grew on the surface, but also connected through the deeply porous interior of the nanoparticles. The compositions of these nanofibrous scaffolds can be manipulated to realize a new design for the dressing and healing of wounded tissues.

Polyvinylidene fluoride

Electrospinning

Biocompatibility

Cellulose acetate

Bacterial Cellulose

10.1016/j.jmrt.2020.10.079

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Citations (55)

Covalently Cross-Linked Polyelectrolyte Complex Nanoparticles with Enhanced Stability against Dissociation at High Ionic Strength

Langmuir (2024)

Xiongyu Chen Zhenhe Zhang Hongtao Zhong Mohamed Ahmed Golnaz Heydari

Polyelectrolyte complex nanoparticles (PECNPs) often fully dissociate into individual polycations (PC) and polyanions (PA) at high salinities. Herein, we introduce a novel type of colloidally stable PECNP in which the PC is cross-linked, in this case branched polyethylenimine (PEI) to limit this dissociation, even in solutions up to 5.2 M NaCl or 5.4 M CaCl2. For cross-linked PECNPs at specified conditions, the size and the PC (poly(vinylsulfonate)) partition coefficient reach equilibrium within the first 24 h and change very little for 7 weeks. From the determination of the released polyanion concentration over a wide range in PEI protonation degree (f), it was found that strong nonelectrostatic (hydrophobic) as well as electrostatic interactions between the PC and PA control the degree of dissociation. The electrostatic repulsion from the PEI chains on the surface provided long-term colloidal stability with PECNP hydrodynamic diameters on the order of 200 to 300 nm. The ability to achieve partial dissociation of a PECNP up to ultrahigh salinity creates new opportunities in fundamental experimental and theoretical studies of PECNP with relevance to controlled release in subsurface energy and environmental applications.

Polyethylenimine

10.1021/acs.langmuir.4c02921

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Retraction to “Silver-Doped Cadmium Selenide/Graphene Oxide-Filled Cellulose Acetate Nanocomposites for Photocatalytic Degradation of Malachite Green toward Wastewater Treatment”

ACS Omega (2023)

Mohamed Ahmed Ahmed Esmail Shalan Mohamed Afifi M. M. El–Desoky S. Lanceros‐Méndez

[This retracts the article DOI: 10.1021/acsomega.1c02667.].

Malachite green

Degradation

Cellulose acetate

Cadmium oxide

Cadmium selenide

10.1021/acsomega.3c05698

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Citations (0)

Clinical and safety outcomes of BeEAM (Bendamustine, Etoposide, Cytarabine, Melphalan) versus CEM (Carboplatin, Etoposide, Melphalan) in lymphoma patients as a conditioning regimen before autologous hematopoietic cell transplantation

BMC Cancer (2024)

Mohamed A. Eltelbanei Noha A. El‐Bassiouny Mahmoud Salah Abdalla Mohamed Ahmed Rehab H. Werida

Autologous stem cell transplantation (ASCT) is a pivotal treatment for lymphoma patients. The BeEAM regimen (Bendamustine, Etoposide, Cytarabine, Melphalan) traditionally relies on cryopreservation, whereas the CEM regimen (Carboplatin, Etoposide, Melphalan) has been optimized for short-duration administration without the need for cryopreservation. This study rigorously compares the clinical and safety profiles of the BeEAM and CEM regimens.

Melphalan

Carboplatin

Plerixafor

Bendamustine

Carmustine

Autologous stem-cell transplantation

10.1186/s12885-024-12694-9

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A comparative study of diesel engine fueled by Jatropha and Castor biodiesel: Performance, emissions, and sustainability assessment

Process Safety and Environmental Protection (2024)

Mohamed Ahmed Tiemin Xuan Waleed A Abdel-Fadeel Hassan Mustafa Salama Abdelhady

Jatropha

10.1016/j.psep.2024.05.137

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Citations (14)

Electrospun nanofibrous scaffolds of polycaprolactone containing binary ions of Pd/vanadate doped hydroxyapatite for biomedical applications

Journal of Drug Delivery Science and Technology (2022)

M.A. El‐Morsy M. Afifi Mohamed Ahmed Nasser S. Awwad Hala A. Ibrahium

Polycaprolactone

Electrospinning

Vanadate

10.1016/j.jddst.2022.103153

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Citations (6)

IMPROVEMENT OF CATCHES BY SHRIMP TRAWL GEAR, IN BARDAWIL LAGOON, NORTH SINAI, EGYPT

Sinai Journal of Applied Sciences/Sinai Journal of Applied Sciences (2016)

Ola Abd El-Hady Gaber Ibrahim Mohamed Ahmed

Four types of shrimp trawl nets 4, 5, 7.5 and 10 mm mesh sizes were used to assess the efficiency of various shrimp trawl nets modification to select and reduce the catch.The catches were affected by different meshes.After five months (Fifteen fishing trips) average catches was calculated per mesh size as follows: 11.11, 10.83, 7 and 6.24 kg for 4, 5, 7.5 and 10 mm, respectively.Average weights of targeted and non-targeted catches were calculated as follows: 1.39, 1.64, 1.4 and 1.31 kg and 9.72, 9.19, 5.6 and 4.93 kg for the same models, respectively.Discarded fish were reducing significantly (P≤0.5) with increasing of mesh sizes, where increasing mesh size up to 7.5 and10 mm in a trawl end was limited for discards and shrimp No.3.Results indicate that substantial improvement in size-fish for shrimp is achieved by switching from the conventional 4 mm-mesh sizes to a 10 mm-mesh size.The minimum mesh size of the shrimp trawl especially used in shrimp fishery must be 7.5 mm in order to protect fish stocks and optimum catch efficiency for the future.On the economic level, the study showed that the use of 7.5 mm as a mesh size will slightly decrease the total income on a short term but will protect fish stock and secure a profitable on long term.Hence, there is a need to identify the potential long and short-term benefits by lagoon management.

10.21608/sinjas.2016.78636

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S3714 A Rare Case of Glomus Tumor of the Stomach Presenting With Upper Gastrointestinal Bleeding

The American Journal of Gastroenterology (2022)

Wael T. Mohamed Vinay Jahagirdar Mohamed Ahmed Ifrah Fatima Hasan Bader

Introduction: Glomus tumors are mesenchymal neoplasms arising from glomus bodies – thermoregulatory arteriovenous shunts, mainly located in the extremities. Gastrointestinal (GI) glomus tumors are rare, with gastric involvement being even less common. Given their rarity and non-specific presentation, they are a challenge to diagnose. Case Description/Methods: A 27-year-old female with no significant past medical history presented with new-onset melena and lightheadedness. Her hemoglobin (Hb) was 6.5 g/dl. EGD showed a single 15-mm cratered ulcer with an overlying blood clot in the gastric body. An endoclip was placed for site marking. Hb continued to fall and multiple blood transfusions were needed. CT abdomen showed a 3-cm rounded prominence along the inferior wall of the gastric antrum, adjacent to the metallic clip. Repeat EGD revealed a fresh clot and oozing from previous site. No discrete vessel or lesion was visible. Hemostasis was achieved with epinephrine injection. Hb remained stable in the 7s and patient was discharged. She re-presented to the ER 2 days later with dizziness and melena. BP was 89/65 and Hb was 5.2 g/dl. On EGD, an ulcer with an adherent clot was seen in the gastric antrum. This appeared to arise from a 1-2 cm submucosal nodule, suggestive of an ulcerated GIST. The defect was closed with endoclips. Hb continued to drop, and surgery was consulted, who proceeded with laparoscopic robotic-assisted local wedge resection of the bleeding gastric mass. Post-operative course was uneventful. The fluctuation in Hb stopped. On histopathology, proliferation of glomus cells around blood cells was seen. Immunohistochemistry (IHC) was positive for calponin and actin, consistent with a glomus tumor. On a follow-up visit 4 weeks later, patient reported resolution of symptoms (Figure 1). Discussion: Gastric glomus tumors commonly present with epigastric pain. GI bleeding is seen in 1/4th of the cases, when the tumors bulge towards the mucosa and ulcerate. EUS can help identify their origin from the submucosa and muscularis propria, though EUS-guided biopsy may cause bleeding. Radiological appearance mimics hypervascular gastric tumors like GIST and neuroendocrine tumors. These can be differentiated via histopathology and IHC. Glomus tumors are composed of vasculature surrounded by small, monomorphic cells without atypia. IHC is suggestive of smooth muscle differentiation with positive actin and vimentin. Surgical resection is preferred. Cases of recurrence and malignant transformation have been reported.Figure 1.: CT scan of the abdomen showing a 3 cm heterogeneous slightly rounded prominence along the inferior wall. (B) EGD showing A 1-2 cm submucosal nodule with an overlying bloody ulcerated mucosa in (A). (C) Classic features of glomus tumor with solid sheets of neoplastic cells in a background of blood vessels with varying caliber (hematoxylin and eosin, magnification 200×). Table 1. - Subtypes of glomus tumors Type Incidence Characteristics Solid 75% Mainly composed of glomus cells nests. Glomangioma 20% Cavernous hemangioma-like vascular structures, surrounded by glomus cells. Glomangiomyoma 5% Glomus cells resemble mature smooth muscle.

Melena

Glomus tumor

Gastrointestinal bleeding

10.14309/01.ajg.0000871496.23443.a5

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Manufacturing of Nano-Surface Composites on AA7075 Using Friction Stir Processing for Military Vehicle and Transportation Applications

International Conference on Aerospace Sciences and Aviation Technology (2013)

M. Refat Mohamed Ahmed Iman El-Mahallawi

Friction stir processing (FSP) is solid state process that has been used recently for microstructural modification and surface composite development. In this study FSP has been used to incorporate Al2O3 nanoparticles on the surface of AA7075 with the aim of manufacturing low density high hardness surface nanocomposites for military vehicles andtransportation applications. The Al2O3 nanoparticles were packed into grooves of 1mm width and 7.5mm depth that were machined in 15mm thick plates of AA7075. The FSP was done using FSP tool of cylindrical probe of 6mm diameter and 20mm diameter shoulder. The tool rotation rate and tool travel speed were selected based on available literature to produce uniform dispersion of Al2O3 nanoparticles. The effect of post processing heat treatment after incorporating Al2O3nanoparticles into different temper conditions of AA7075-T6 and AA7075-O was investigated. The developed nanocomposites were investigated and characterized using optical microscopy, scanning electron microscopy, and hardness testing.

Friction Stir Processing

Surface Modification

10.21608/asat.2013.22053

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