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Artigo Revisado por pares

Mahmoud Mohammaden, Stephen English, Christopher J. Stapleton, Eman M. Khedr, Ahmed Shoyb, Ahmed Hegazy, Ahmed Elbassiouny,

Background Flow diversion (FD) is a common treatment modality for complex intracranial aneurysms. A major concern regarding the use of FD is thromboembolic events (TEE). There is debate surrounding the optimal antiplatelet regimen to prevent TEE. We aim to evaluate the safety and efficacy of ticagrelor as a single antiplatelet therapy (SAPT) for the prevention of TEE following FD for complex aneurysm treatment. Methods A retrospective review of a prospectively maintained neuroendovascular database ...

Tópico(s): Acute Ischemic Stroke Management

2020 - BMJ | Journal of NeuroInterventional Surgery

Revisão Revisado por pares

Ahmed S. Doghish, Maghawry Hegazy, Ahmed Ismail, Hesham A. El-Mahdy, Elsayed G.E. Elsakka, Samy Y. Elkhawaga, Mohamed A. Elkady, Amr Mohamed Yehia, Nourhan M. Abdelmaksoud, Mahmoud Mohamed Mokhtar,

Osteosarcoma (OS) is one of the most common bone cancers that constantly affects children, teenagers, and young adults. Numerous epigenetic elements, such as miRNAs, have been shown to influence OS features like progression, initiation, angiogenesis, and treatment resistance. The expression of numerous genes implicated in OS pathogenesis might be regulated by miRNAs. This effect is ascribed to miRNAs' roles in the invasion, angiogenesis, metastasis, proliferation, cell cycle, and apoptosis. Important ...

Tópico(s): Circular RNAs in diseases

2023 - Elsevier BV | Pathology - Research and Practice

Artigo Acesso aberto Revisado por pares

Amira A. Sallam, Mohammed A. El‐Magd, Mona M. Ahmed, Heba I. Ghamry, Mohammad Y. Alshahrani, Rabab A. Hegazy, Ahmed Magdy, Magdy F. Abou El-Fotoh,

Recently, we reported that quercetin (Que) could alleviate immunotoxicity induced by pristine multi-walled carbon nanotubes (MWCNTs) in mice. In the present study, we explored whether Que could also relieve MWCNTs-induced neurotoxicity. MWCNTs injection induced a dose-dependent neurotoxic effect in mice as evidenced by increased oxidative stress, inflammation, and pyroptosis in the brain. However, treatment with Que ameliorated MWCNTs-induced neurotoxicity as revealed by 1) elevated acetylcholinesterase ( ...

Tópico(s): Curcumin's Biomedical Applications

2022 - Elsevier BV | Biomedicine & Pharmacotherapy

Artigo Acesso aberto Revisado por pares

Sherin K. Ali, Ahmed R. Hamed, Maha M. Soltan, Ali M. El-Halawany, Usama M. Hegazy, Ahmed A. Hussein,

The alcoholic extract of Adhatoda vasica showed strong and reversible inhibition of the enzyme acetyl cholinesterase (AChE) with an IC50 = 294 μg/mL. Phytochemical study of the total alcoholic extract of A. vasica yielded four known compounds vasicine, vasicinone, vasicole and anisotine. Vasicine reversibly and competitively inhibited AChE with ki value 11.24 μM. On the other hand, rest of isolated alkaloids showed no/or weak inhibitory effect on AChE. Vasicine showed binding similarity to both galantamine ...

Tópico(s): Cancer therapeutics and mechanisms

2016 - Elsevier BV | South African Journal of Botany

Artigo Revisado por pares

M.A. Hegazy, Ahmed Abdel Nazeer, K. Shalabi,

The inhibition effect of two quaternary ammonium salts namely: N1,N2-didodecyl-N1,N1,N2,N2-tetramethylethane-1,2-diaminium bromide (I) and N-(2-hydroxyethyl)-N,N-dimethyldodecan-1-aminium bromide (II) on the corrosion of copper in 1 M HNO3 has been investigated by polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. Polarization studies showed that these compounds are mixed-type inhibitors. The inhibition efficiency increases with increasing ...

Tópico(s): Analytical Chemistry and Sensors

2015 - Elsevier BV | Journal of Molecular Liquids

Artigo Acesso aberto Revisado por pares

Nadia Z. Shaban, Iman M. Talaat, Fatma H. El-Rashidy, A.Y. Hegazy, Ahmed Sultan,

Postmenopausal osteoporosis is mostly caused by increased bone remodeling resulting from estrogen deficiency. Hormone replacement therapy (HRT) is used to prevent osteoporosis, but it increases the risk for breast cancer, thromboembolism, strokes, and heart attacks. Pomegranate seed oil extract (SOE) is rich in phytoestrogen and antioxidant compounds. To evaluate the therapeutic role of SOE against bone turnover, resorption and osteoporosis induced in ovariectomized rats as a postmenopausal model ...

Tópico(s): Garlic and Onion Studies

2017 - Springer Science+Business Media | The journal of nutrition health & aging

Artigo Revisado por pares

A.S. El-Tabei, M.A. Hegazy, Ahmed H. Bedair, N. El Basiony, M.A. Sadeq,

New cationic amphiphilic substance (DMNAPDAB) (namely: N,N-dimethyl-N-(3-(2-(naphthalene-1-yloxy)acetoxy)propyl)dodecan-1-aminium bromide) was evaluated as corrosion inhibitor. Carbon steel (CS) corrosion behavior in 5% HCl was investigated via electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PP), weight loss (WL), SEM & EDX techniques. Inhibition performance improves with rising DMNAPDAB dosage and falls slightly when the temperature increases. DMNAPDAB adsorption on to CS surface ...

Tópico(s): Hydrogen embrittlement and corrosion behaviors in metals

2021 - Elsevier BV | Journal of Molecular Liquids

Revisão Revisado por pares

Elsayed G.E. Elsakka, Mahmoud Mohamed Mokhtar, Maghawry Hegazy, Ahmed Ismail, Ahmed S. Doghish,

The endocytosis mechanism is a complicated system that is essential for cell signaling and survival. Megalin, a membrane-associated endocytic receptor, and its related proteins such as cubilin, the neonatal Fc receptor for IgG, and NaPi-IIa are important in receptors-mediated endocytosis. Physiologically, megalin uptakes plasma vitamins and proteins from primary urine, preventing their loss. It also facilitates tubular retrieval of solutes and endogenous components that may be involved in modulation ...

Tópico(s): Complement system in diseases

2022 - Elsevier BV | Life Sciences

Artigo

El‐Sayed A. Hegazy, Ahmed M. Dessouki, Ahmed Rabie, Isao Ishigaki,

Abstract Some properties of the membranes obtained by preirradiation grafting of acrylic acid onto poly(tetrafluoroethylene‐perfluorovinyl ether) copolymer (PFA) films have been investigated. The dimensional change caused by grafting and swelling behavior, water uptake, electrical conductivity, and mechanical properties of the grafted films were found to increase as the grafting proceeds. The influence of the preparation conditions (such as preirradiation dose, monomer concentration, grafting temperature, ...

Tópico(s): Advanced Battery Technologies Research

1984 - Wiley | Journal of Polymer Science Polymer Chemistry Edition

Artigo

El‐Sayed A. Hegazy, Ahmed M. Dessouki, M. M. El-Dessouky, Naeem M. El‐Sawy,

Tópico(s): biodegradable polymer synthesis and properties

1985 - Pergamon Press | Radiation Physics and Chemistry (1977)

Artigo

El‐Sayed A. Hegazy, Ahmed M. Dessouki, H. A. El-Boohy,

Abstract Radiation‐induced graft polymerization of acrylamide (AAm) onto low‐density polyethylene(LDPE) film has been investigated. The appropriate reaction conditions at which the graft polymerization was carried out successfully were selected. It was observed that the grafting process was enhanced remarkably by using distilled water as diluent. In this grafting system ammonium ferrous sulphate (Mohr's salt) was used as inhibitor to minimize the homopolymerization of AAm and the suitable concentration ...

Tópico(s): Plant Disease Management Techniques

1986 - Wiley | Journal of Polymer Science Part A Polymer Chemistry

Artigo

El‐Sayed A. Hegazy, Ahmed M. Dessouki, N.B. El-Assy, Naeem M. El‐Sawy, M.A. Abd El‐Ghaffar,

Abstract Direct radiation‐induced grafting of aqueous acrylic acid (AAc) onto poly(tetrafluoroethylene‐ethylene) (ET) film has been studied. The effect of grafting conditions such as monomer concentration, exposure dose, dose rate, and film thickness on the grafting yield was investigated. The dependence of the grafting rate on monomer concentration was found to be 1.2 order. The dependence of the grafting rate on dose rate was found to be 0.6 order regardless of the film thickness. The relationship ...

Tópico(s): Fiber-reinforced polymer composites

1992 - Wiley | Journal of Polymer Science Part A Polymer Chemistry

Artigo Revisado por pares

Naeem M. El‐Sawy, M.A. Abd El‐Ghaffar, El‐Sayed A. Hegazy, Ahmed M. Dessouki,

Grafting of aqueous acrylic acid onto poly(tetrafluoroethylene-co-perfluorovinyl ether) films has been carried out using γ-irradiation. Copper and chromium complexes have been prepared by treating the grafted films with aqueous solutions of copper and chromium sulphates. The formation of polymer/metal complexes has been confirmed spectrophotometrically by u.v. and colour measurements. Electrical and mechanical properties of films of the complexes have been studied. Thermal analysis and study of ...

Tópico(s): Photopolymerization techniques and applications

1992 - Elsevier BV | European Polymer Journal

Artigo Revisado por pares

Mostafa M. El‐Sheekh, A. M. Ismail, Mostafa El-Abd, Eman M. Hegazy, Ahmed I. El‐Diwany,

The production of a notable and highly effective pectinase by the local fungal strain Aspergillus carneus NRC1 utilizing the abundant Egyptian orange peels and pulps (OPP) scraps excluded in the orange juice and canning industry was achieved in 5-day submerged fermentation (SMF) cultures, at temperature and pH ranges of 30–55 °C and 5.0–5.5, respectively. Fresh or thawed OPP (6%, w/v) were the most preferable sole carbon source. Pectinase activity was dramatically stimulated by ammonium sulphate as ...

Tópico(s): Enzyme Production and Characterization

2008 - Elsevier BV | International Biodeterioration & Biodegradation

Artigo

Messai Laid, Mohamed‐Elamir F. Hegazy, Ahmed A. Ahmed, Kalla Ali, Djaballah Belkacemi, Shinji Ohta,

The phytochemical investigation of the methylene chloride/methanol extract of the aerial parts of Artemisia herba-alba afforded two new natural sesquiterpene lactones 1β,9β-diacetoxyeudesm-3-en-5α,6β,11βH-12,6-olide (1) and 1β,9β-diacetoxyeudesm-4-en-6β,11βH-12,6-olide (2). The structures of the compounds were determined by comprehensive NMR studies, including DEPT, COSY, NOESY, HMQC, HMBC and HRMS.

Tópico(s): Phytochemistry and Biological Activities

2008 - Elsevier BV | Phytochemistry Letters

Artigo

M. A. Abdel-Rahman Tahany, Ahmad K. Hegazy, Ahmed M. Sayed, Hanan F. Kabiel, Taha S. El‐Alfy, S. M. El-Komy,

Three plants were used in this study: Moringa pregrina, Achillea fragrantissimaand Coleome droserifolia. Six active constituents were separated from n-hexane and ethyl acetate fractions of Moringa pregrina. These active constituents were lupeol acetate, α-amyrin, β-amyrin, β-sitosterol, β-sitosterol-3-O- β-D-glucoside and apignin were assayed individually and in combination against pathogenic bacteria and fungi. All constituents were proved to be more antibacterial than antifungal agents. Aspergillus ...

Tópico(s): Phytochemistry and Bioactivity Studies

2010 - Academic Journals | Journal of Yeast and Fungal Research

Artigo Revisado por pares

A. M. Badawi, M.A. Hegazy, Ahmed El-Sawy, Hend Ahmed, W.M. Kamel,

A series of alkyl dimethylisopropylammonium hydroxide cationic surfactants (DEDIAOH, DODIAOH and HEDIAOH) was synthesized and characterized. The surface properties such as the critical micelle concentration (CMC), the effectiveness of surface tension reduction (ΠCMC), surface excess concentration (Γmax) and surface area per molecule (Amin) have been determined by means of surface tension measurements. The degree of counter ion dissociation (β) and the free energy of micellization (ΔGmic) were calculated. ...

Tópico(s): Environmental Chemistry and Analysis

2010 - Elsevier BV | Materials Chemistry and Physics

Artigo Revisado por pares

Tarek Hegazy, Ahmed Elhakeem,

This paper introduces a new formulation for large-scale combinatorial bilevel optimization problems that involve integer, discrete, two-level decisions. The most vivid example where the new technique most applies is the life cycle optimization needed to allocate repair types and repair timings to a number of infrastructure assets (e.g., building components). Combining these decisions into a single optimization for hundreds of assets simultaneously makes the optimization problem complex and prohibitive. ...

Tópico(s): Water Systems and Optimization

2011 - NRC Research Press | Canadian Journal of Civil Engineering

Artigo Acesso aberto Revisado por pares

Tarek Hegazy, Ahmed Elhakeem, Shipra Singh Ahluwalia, Mohamed Attalla,

Abstract: Among the various asset management functions that support capital renewal decisions, both inspection and fund‐allocation are very challenging in terms of time, cost, and technology. To support these functions, this article introduces two unique techniques that can be implemented, individually or combined, into any asset management system: (1) Focused‐Inspection Technique (FIT); and (2) Multiple Optimization and Segmentation Technique (MOST). FIT improves inspection by incorporating an analysis ...

Tópico(s): BIM and Construction Integration

2011 - Wiley | Computer-Aided Civil and Infrastructure Engineering

Artigo Acesso aberto Revisado por pares

Mohamed‐Elamir F. Hegazy, Ahmed A. El‐Beih, Alaa Y. Moustafa, Abdelhamed A. Hamdy, Montaser A. Alhammady, Rehab M. Selim, Mohamed Abdel‐Rehim, Paul W. Paré,

One new cembrane diterpene, 2R,7R,8R-dihydroxydeepoxysarcophine (1), together with three known compounds, 7alpha,8beta-dihydroxydeepoxysarcophine (2), 7beta-acetoxy-8alpha-hydroxydeepoxysarcophine (3), and sarcophine (4), have been isolated from the Red Sea soft coral Sarcophyton glaucum. Their structures were determined using 1D and 2D NMR spectroscopy. 7beta-Acetoxy-8alpha-hydroxydeepoxysarcophine (3) exhibits cytotoxic activity against HepG2, HCT-116, and HeLa cells with IC50 values of 3.6, 2.3, and ...

Tópico(s): Microbial Natural Products and Biosynthesis

2011 - SAGE Publishing | Natural Product Communications

Artigo

El‐Sayed A. Hegazy, Ahmed M. Dessouki, Naeem M. El‐Sawy, M.A. Abd El‐Ghaffar,

Abstract A study has been made on the graft copolymers obtained by radiation‐induced grafting of acrylic acid onto poly(tetrafluoroethylene‐ethylene) (ET) films. The conversion of the graft copolymer into metal acrylate copolymer complex was carried out by treatment with different metal salts. Such a prepared graft copolymer–metal complex was confirmed by different methods: IR, UV spectrometry, degree of coloration, and x‐ray fluorescence. Some selected properties of the graft copolymer–metal complexes ...

Tópico(s): Silicone and Siloxane Chemistry

1993 - Wiley | Journal of Polymer Science Part A Polymer Chemistry

Artigo Revisado por pares

Hassan A. Abd El‐Rehim, El‐Sayed A. Hegazy, Ahmed Mahmoud Abdelhaleem Ali, Ahmed Rabie,

Tópico(s): Nanocomposite Films for Food Packaging

2004 - Elsevier BV | Journal of Photochemistry and Photobiology A Chemistry

Artigo Revisado por pares

Tarek Hegazy, Ahmed Elhakeem, Emad Elbeltagi,

This paper presents an innovative model for scheduling, resource planning, and cost optimization of large construction and/or maintenance programs that involve multiple distributed sites. The proposed distributed scheduling model (DSM) employs an information system to store data related to various work sites, activities' optional construction methods, and available resources. The DSM also incorporates a scheduling algorithm that is resource focused, and maintains crew work continuity under any sequence ...

Tópico(s): Elevator Systems and Control

2004 - American Society of Civil Engineers | Journal of Construction Engineering and Management

Artigo Revisado por pares

A.S. El-Tabei, M.A. Hegazy, Ahmed H. Bedair, M.A. Sadeq,

Abstract A novel Tri‐cationic surfactant was synthesized, purified and characterized. The critical micelle concentration value of the prepared surfactant was determined by surface tension and conductivity measurements. The surface parameters were calculated by surface tension measurements. The relationship between the surface properties and the corrosion inhibition efficiency of the prepared surfactant was discussed. The inhibition effect of the novel Tri‐cationic surfactant on carbon steel corrosion ...

Tópico(s): Surfactants and Colloidal Systems

2013 - Wiley | Journal of Surfactants and Detergents

Artigo

Tamer Awad Ali, E. M. S. Azzam, M.A. Hegazy, Ahmed F. El‐Farargy, Ali A. Abd‐Elaal,

In the present study newly developed potentiometric sensors for determination of zinc(II) are presented. The proposed potentiometric method was based on the fabrication of modified carbon paste (MCPE; electrode X) and modified gold nanoparticles-carbon paste (GNPs-CPE; electrode IX) sensors. A mercapto compound of 1,4-bis(5-mercaptopentyloxy)-benzene (BMPB) alone or self-assembled on gold nanoparticles was used as modifier to construct electrode (X) and electrode (IX) sensors, respectively. The prepared ...

Tópico(s): Electrochemical sensors and biosensors

2013 - Elsevier BV | Journal of Industrial and Engineering Chemistry

Artigo Revisado por pares

Mohamed‐Elamir F. Hegazy, Ahmed R. Hamed, Tarik A. Mohamed, Abdessamad Debbab, Seikou Nakamura, Hisashi Matsuda, Paul W. Paré,

New sesquiterpenes tanacetolide A–C ( 1–3 ) were isolated from a Tanacetum sinaicum extract together with known compounds ( 4–10 ).

Tópico(s): Phytochemistry and Biological Activities

2015 - Royal Society of Chemistry | RSC Advances

Artigo

Mohamed‐Elamir F. Hegazy, Ahmed R. Hamed, Ali M. El-Halawany, Taha A. Hussien, Sara Abdelfatah, Shinji Ohta, Paul W. Paré, Essam Abdel‐Sattar, Thomas Efferth,

Diterpenoids salvimulticanol (1) and salvimulticaoic acid (2) together with known diterpenoid (3-6) were isolated from Salvia multicaulis. Structures were elucidated by spectroscopic techniques including HRESIMS as well as 1D-, and 2D-NMR. In-vitro cytotoxicity was assayed against human cancer cell lines. As several metabolites exhibited activity against drug-resistance lines, compounds were screened against a panel of human drug-sensitive and multidrug-resistant cancer lines. A proposed biosynthetic ...

Tópico(s): Biological Activity of Diterpenoids and Biflavonoids

2018 - Elsevier BV | Fitoterapia

Capítulo de livro Revisado por pares

Aida A. Abd El‐Wahed, Shaden A. M. Khalifa, Bassem Y. Sheikh, Mohamed A. Farag, Aamer Saeed, Fayaz Ali Larik, Ufuk Koca Çalışkan, Mohamed F. Alajmi, Moustapha Hassan, Habibah A. Wahabi, Mohamed‐Elamir F. Hegazy, Ahmed F. Algethami, Sabrina Büttner, Hesham R. El‐Seedi,

Nature has provided many drugs capable of treating and alleviating human diseases. Terrestrial plants, bacteria, insects, fungi, and bee products have played major roles in traditional medicine. Secondary metabolites from a range of bee products, such as honey, pollen, propolis, royal jelly, and bee venom, represent a huge repository of chemical biodiversity, providing renewable and rewarding sources of therapeutic substances, either directly from nature or as synthesized analogues. Bee venom in ...

Tópico(s): Bee Products Chemical Analysis

2018 - Elsevier BV | Studies in natural products chemistry