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      • KCI등재

        Synthesis and cytotoxic activity of certain trisubstituted azetidin- 2-one derivatives as a cis-restricted combretastatin A-4 analogues

        Salwa Elmeligie,Azza T. Taher,Nadia A. Khalil,Ahmed H. El-said 대한약학회 2017 Archives of Pharmacal Research Vol.40 No.1

        Novel series of 1,3,4-trisubstituted azetidin-2-one derivatives 8a–p were synthesized and proposed ascytotoxic agents acting via inhibition of tubulin at thecolchicine binding site. The design of the target compoundswas based upon modification in the structure of the vasculartargeting agent combretastatin A-4 (CA-4). The cisdouble bond linker in CA-4 was replaced with the azetidin-2-one ring aiming to prevent the cis/trans isomerizationthat suppresses the activity of CA-4, thereby enhancing itsantiproliferative activity. All new compounds were investigatedin vitro against MCF-7 and HCT-116 cell lines. Theinhibition of tubulin polymerization by four most potentcompounds 8g, 8j, 8n and 8o was also evaluated. Thesynthesis of the final targets was achieved adopting Staudingerreaction. Molecular modeling studies were performedto rationalize the biological results.

      • KCI등재
      • SCOPUSKCI등재

        Cardenolides and β-Sitosterol Glucoside from Pergularia tomentosa L.

        Ahmed A. Gohar,M. M. El Olemy,Essam Abdel Sattar,M. El Said,M. Niwa 한국생약학회 2000 Natural Product Sciences Vol.6 No.3

        The aerial parts of Pergularia tomentosa L. afforded three cardenolides, desglucouzarin, coroglaucigenin and uzarigenin, in addition to β-sitosterol glucoside. The isolated compounds were identified by physical and spectral means, including IR, UV, [α]_D 1D-, 2D-NMR and FAB-MS experiments. The cardenolides, ghalakinoside, calactin and pergularoside previously reported from roots, were also identified in the aerial parts.

      • SCIESCOPUSKCI등재

        Water Vapor Adsorption and Hydrogen Peroxide Decomposition on Date Pit Carbonization Products

        A.M. Youssef,Th. El-Nabarawy,S.A. Sayed Ahmed,W.E. Rashwan 한국탄소학회 2005 Carbon Letters Vol.6 No.4

        Carbonization products C1, C2, C3, C4 and C5 were prepared by the carbonization of date pit in limited air, at 500, 600, 700, 800 and 1000℃, respectively. C1-V-600, C3-V-600, C1-V-1000 and C3-V-1000 were prepared by thermal treatment of C1 and C3 under vacuum at 600 and 1000℃. The textural properties were determined from nitrogen adsorption at 77 K and from carbon dioxide adsorption at 298 K. The surface pH, the FTIR spectra and the acid and base neutralization capacities of some carbons were investigated. The amounts of surface oxygen were determined by out-gassing the carbon-oxygen groups on the surface as CO2 and CO. The adsorption of water vapor at 308 K on C1, C2, C3 and C4 was measured and the decomposition of H2O2 at 308 K was also investigated on C1, C2, C3, C4 and C5. The surface area and the total pore volume decreased with the rise of the carbonization temperature from 500 to 1000℃. The adsorption of water vapor is independent on the textural properties, while it is related to the amount of acidic carbon-oxygen groups on the surface. The catalytic activity of H2O2 decomposition does not depend on the textural properties, but directly related to the amount of basic carbon-oxygen complexes out-gassed as CO, at high temperatures.

      • SCOPUSKCI등재

        On Some Fractional Quadratic Integral Inequalities

        El-Sayed, Ahmed M.A.,Hashem, Hind H.G. Department of Mathematics 2020 Kyungpook mathematical journal Vol.60 No.1

        Integral inequalities provide a very useful and handy tool for the study of qualitative as well as quantitative properties of solutions of differential and integral equations. The main object of this work is to generalize some integral inequalities of quadratic type not only for integer order but also for arbitrary (fractional) order. We also study some inequalities of Pachpatte type.

      • Shear behaviour of thin-walled composite cold-formed steel/PE-ECC beams

        Ahmed M. Sheta,Xing Ma,Yan Zhuge,Mohamed A. ElGawady,Julie E. Mills,El-Sayed Abd-Elaal 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.46 No.1

        The novel composite cold-formed steel (CFS)/engineered cementitious composites (ECC) beams have been recently presented. The new composite section exhibited superior structural performance as a flexural member, benefiting from the lightweight thin-walled CFS sections with improved buckling and torsional properties due to the restraints provided by thinlayered ECC. This paper investigated the shear performance of the new composite CFS/ECC section. Twenty-eight simply supported beams, with a shear span-to-depth ratio of 1.0, were assembled back-to-back and tested under a 3-point loading scheme. Bare CFS, composite CFS/ECC utilising ECC with Polyethylene fibres (PE-ECC), composite CFS/MOR, and CFS/HSC utilising high-strength mortar (MOR) and high-strength concrete (HSC) as replacements for PE-ECC were compared. Different failure modes were observed in tests: shear buckling modes in bare CFS sections, contact shear buckling modes in composite CFS/MOR and CFS/HSC sections, and shear yielding or block shear rupture in composite CFS/ECC sections. As a result, composite CFS/ECC sections showed up to 96.0% improvement in shear capacities over bare CFS, 28.0% improvement over composite CFS/MOR and 13.0% over composite CFS/HSC sections, although MOR and HSC were with higher compressive strength than PE-ECC. Finally, shear strength prediction formulae are proposed for the new composite sections after considering the contributions from the CFS and ECC components.

      • SCIESCOPUSKCI등재

        Removal of Pesticide (Oxamyl) from Water using Activated Carbons Developed from Apricot Stones

        El-Nabarawy, Th.,Sayed Ahmed, S.A.,Youssef, A.M. Korean Carbon Society 2007 Carbon Letters Vol.8 No.4

        Four stream- activated carbons were prepared by carbonizing apricot stones at $600^{\circ}C$ followed by gasification with steam at $950^{\circ}C$ to burn-off's=17, 32, 49 and 65%. The textural parameters of these activated carbons were determined from nitrogen adsorption results at 77 K. The total pore volume and the mean pore radius increased with the increase of % burn-off whereas the surface area increased with the increase of burn- off from 17 to 32 and further to 49%. Further increase of burn-off to 65% was associated with a considerable decrease in surface area as a result of pronounced pore widening due to pore erosion. The surface pH values of the carbons investigated range between 7.1 and 8.2. The adsorption of oxamyl onto the activated carbon followed pseudo-second order kinetics and the equilibrium adsorption isotherms fitted Langmuir adsorption model. The adsorption of oxamyl proved to be of the physical type and took place in non-micropores. The amount of oxamyl adsorbed expressed as $q_m$ depends to a large extent to the surface area located in non-micropores $S^{\propto}\;_n$, where a straight line relationship passing through the origin was obtained.

      • KCI등재

        Immune Defense of Rats Immunized with Fennel Honey, Propolis, and Bee Venom Against Induced Staphylococcal Infection

        Sayed, S.M.,El-Ella, Ghada A. Abou,Wahba, Nahed M.,Nisr, Neveen A. El,Raddad, Khaled,Rahman, M.F. Abd El,Hafeez, M.M. Abd El,Aamer, Ahmed Abd El Fattah The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.3

        The objective of this work was to evaluate the potency of bee product-immunized rats to overcome an induced Staphylococcus aureus infection. Forty rats were divided to eight groups: T1, T3, and T5 received, respectively, fennel honey, ethanol, and aqueous propolis extracts orally, and T2, T4, and T6 were administered the respective materials intraperitoneally; T7 received bee venom by the bee sting technique; and T8 was the control group. All groups were challenged by a bovine clinical mastitis isolate of S. aureus. Each rat received 2mL of broth inoculated with $1{\times}10^5$ colony-forming units/mL intraperitoneally. Two weeks post-induced infection all rats were sacrificed and eviscerated for postmortem inspection and histopathological study. Three rats from T8 and one rat from T7 died before sacrifice. Another two rats, one each in T4 and T5, had morbidity manifestations. The remaining experimental animals showed apparently healthy conditions until time of sacrifice. Postmortem inspection revealed that all T8 rats showed different degrees of skeletal muscle and internal organ paleness with scattered focal pus nodules mainly on lungs and livers. All rats of the treated groups showed normal postmortem features except three rats. A dead rat in group T7 showed focal pus nodules on the lung surface only, whereas the affected two rats in groups T4 and T5 appeared normal except with some pus nodules, but much smaller than in the control, scattered on the hepatic surface and mesentery. Histopathological studies revealed that T8 rats had typical suppurative bronchopneumonia and or severe degenerative and necrobiotic changes in hepatic tissues. Three affected rats of the treated groups showed slight bronchopneumonia or degenerative hepatic changes only. The other animals of the treated groups showed completely normal parenchymatous organs with stimulated lymphatic tissues. It was concluded that all tested previously bee product-immunized rats could significantly challenge the induced S. aureus infection (P < .01). The effects were more pronounced in rats that had received fennel honey solution.

      • KCI등재

        Life Span Extension of Caenorhabditis elegans by Novel Pyridoperimidine Derivative

        Ahmed A. R. Sayed,Kamal M. El-Shaieb,Aboul-Fetouh E. Mourad 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.1

        Zwitterions formed from the addition of triphenylphosphine to dialky acetylene-dicarboxylates attack the nucleus of both 1H-perimidine (1) and 1H-benzo[d]imidazole (9) to form novel pyrido[1,2,3-cd]perimidine and imidazo[4,5,1-ij]quinoline derivatives in moderate yields (64-72%). The biological activity of the products has been studied. Compound 3a was found to extend life span of wild type Caenorhabditis elegans under standard laboratory conditions. Both heat stress and induced chemical stress resistance of wild type C. elegans were improved in a reverse dose-dependent manner due to 3a treatment. In addition, treatment of worms with compound 3a significantly attenuated the formation of advanced glycation end products in a reverse dose-dependent manner.

      • Quercetin Confers Tumoricidal Activity Through Multipathway Mechanisms in A N-Methylnitrosourea Rat Model of Colon Cancer

        Ahmed, Hanaa H,Aglan, Hadeer A,Zaazaa, Asmaa M,Shalby, Aziza B,Toumy, Sayed A El Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.11

        Objective: This research was conducted to explore mechanisms behind the potency of quercetin in inhibiting colon cancer induced in an experimental model. Materials and Methods: Forty adult male rats of Wistar strain were distributed into 4 groups; a negative control group, a colon cancer bearing group, a quercetin-treated group and a 5-fluorouracil (5-FU)-treated group. Serum TAG72 and GAL3 levels were quantified by ELISA. Colonic Wnt5a and Axin-1 gene expression was estimated by PCR. In addition, colonic tissues were subjected to immunohistochemical examination of Bax expression and histological investigation of histopathological alterations. Results: Quercetin elicited significant reduction in serum TAG72 and GAL3 levels, in addition to significant suppression of colonic Wnt5a gene expression and amplification of colonic Axin-1 gene expression. Also, it caused moderate positive reaction for Bax in mucosal epithelium. Conclusion: The present research provides experimental evidence about the activity of quercetin in the colon cancer of rats. Inhibitory effects on cancer development might be ascribable to regulatory action on Wnt signaling and induction of apoptosis.

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