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      • KCI등재

        New ursane triterpenoids from Ficus pandurata and their binding affinity for human cannabinoid and opioid receptors

        Amgad I. M. Khedr,Sabrin R. M. Ibrahim,Gamal A. Mohamed,Hany E. A. Ahmed,Amany S. Ahmad,Mahmoud A. Ramadan,Atef E. Abd El-Baky,Koji Yamada,Samir A. Ross 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

        Phytochemical investigation of Ficus pandurataHance (Moraceae) fruits has led to the isolation of two newtriterpenoids, ficupanduratin A [1b-hydroxy-3b-acetoxy-11a-methoxy-urs-12-ene] (11) and ficupanduratin B [21ahydroxy-3b-acetoxy-11a-methoxy-urs-12-ene] (17), alongwith 20 known compounds: a-amyrin acetate (1), a-amyrin(2), 3b-acetoxy-20-taraxasten-22-one (3), 3b-acetoxy-11amethoxy-olean-12-ene (4), 3b-acetoxy-11a-methoxy-12-ursene (5), 11-oxo-a-amyrin acetate (6), 11-oxo-b-amyrinacetate (7), palmitic acid (8), stigmast-4,22-diene-3,6-dione(9), stigmast-4-ene-3,6-dione (10), stigmasterol (12), b-sitosterol(13), stigmast-22-ene-3,6-dione (14), stigmastane-3,6-dione (15), 3b,21b-dihydroxy-11a-methoxy-olean-12-ene (16), 3b-hydroxy-11a-methoxyurs-12-ene (18), 6-hydroxystigmast-4,22-diene-3-one (19), 6-hydroxystigmast-4-ene-3-one (20), 11a,21a-dihydroxy-3b-acetoxy-urs-12-ene(21), and b-sitosterol-3-O-b-D-glucopyranoside (22). Compound21 is reported for the first time from a natural source. The structures of the 20 compounds were elucidated on thebasis of IR, 1D (1H and 13C), 2D (1H–1H COSY, HSQC,HMBC and NOESY) NMR and MS spectroscopic data, inaddition to comparison with literature data. The isolatedcompounds were evaluated for their anti-microbial, antimalarial,anti-leishmanial, and cytotoxic activities. In addition,their radioligand displacement affinity on opioid andcannabinoid receptors was assessed. Compounds 4, 11, and15 exhibited good affinity towards the CB2 receptor, withdisplacement values of 69.7, 62.5 and 86.5 %, respectively. Furthermore, the binding mode of the active compounds inthe active site of the CB2 cannabinoid receptors was investigatedthrough molecular modelling.

      • KCI등재

        Bioactive compounds from Withania somnifera dun and their toxicity against some piercing sucking pests

        Ragab Amany,Taher Mohamed A.,El-Rafey Helmy H.,El-Rokh Ahmed Ramadan 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

        Piercing sucking pests are destructive to many strategic crops all over the world. Botanical pesticides can be used to control these pests. A new withanolide derivative 3 named sominone A ((20R,22R)-1α,3β,20,27-tetrahydroxywitha- 5,24-dienolide) was isolated from the alkaloid fraction of the whole plant of Withania somnifera. In addition, there are three known compounds named withasomine 1, methyl isoferulate 2, and coagulin Q 4 were also isolated. The structures of isolated compounds were identified using different spectroscopic methods such as 1D, 2D NMR, and HRESIMS spectroscopy. The alkaloid fraction and the four isolated compounds were tested for their pesticidal activity against four piercing sucking pests (Aphis craccivora Koch, Bemisia tabaci Gennadius, Nezara viridula Linnaeus, and Tetranychus urticae Koch) that attack many strategic crops under laboratory conditions, along with azadirachtin (Okios 3.2% EC) as a positive control. The results showed that the alkaloid compound (withasomine 1) was the most toxic to A. craccivora, B. tabaci, N. viridula, and T. urticae, with LC50 values of 15.44, 36.61, 85.11, and 128.28 ppm, respectively, compared with the control. Withanolide compounds had moderate effects on all tested pests. Biochemical parameters of six enzymes; α-esterase, β-esterase, chitinase, acetylcholinesterase, glutathione-S-transferase, and peroxidase of A. craccivora were estimated at the LC50 value of the most potent compound, withasomine 1 and the values were 38.83, 72.86, 31.45, 506.4, 2.62, and 251.0, respectively. The results demonstrated that all enzymes activity levels were increased compared with the control except a remarkable inhibition in AChE enzyme level was observed compared with control. Therefore, the alkaloid fraction of W. somnifera is a promising extract that contains many active compounds that can be used as a natural pesticide against many harmful pests in agriculture crops.

      • SCOPUSKCI등재

        ON FUZZY BITOPOLOGICAL SPACES IN ŠOSTAK'S SENSE

        Ramadan, A.A.,Abbas, S.E.,El-Latif, A.A. Abd Korean Mathematical Society 2006 대한수학회논문집 Vol.21 No.3

        In this paper, we used the supra fuzzy topology which generated from a fuzzy bitopological space [1] to introduce and study the concepts of continuity (resp. openness, closeness) of mapping, separation axioms and compactness for a fuzzy bitopological spaces. Our definition preserve much of the correspondence between concepts of fuzzy bitopological spaces and the associated fuzzy topological spaces.

      • KCI등재

        On L-fuzzy pre-proximities and L-fuzzy interior operators

        A. A. Ramadan,M. A. Usama,M. A. Reham 원광대학교 기초자연과학연구소 2019 ANNALS OF FUZZY MATHEMATICS AND INFORMATICS Vol.17 No.2

        In this paper, we introduce the notions of $L$-fuzzy pre-proximities, $L$-fuzzy interior operators in complete residuated lattices. Moreover, we investigate the relations among the $L$-fuzzy pre-proximities, $L$-fuzzy interior operators and $L$-fuzzy topologies. We show that there is a Galois correspondence between the category of separated $L$-fuzzy interior spaces and that of separated $L$-fuzzy pre-proximity spaces.

      • SCIESCOPUSKCI등재

        SUPRA FUZZY CONVERGENCE OF FUZZY FILTERS

        Ramadan, A.A.,El-Latif, A.A. Abd Korean Mathematical Society 2008 대한수학회보 Vol.45 No.2

        We introduce and study the notions of supra fuzzy convergence of fuzzy filters, $s{\gamma}$-fuzzy open (closed) sets, $s{\gamma}($s{\gamma}^*)$-fuzzy continuous and $s{\gamma}$-fuzzy open mapping. Also. we investigate some of fundamental properties of these notions.

      • KCI등재

        Smooth uniform spaces

        Ramadan, A.A.,El-Dardery, M.,Kim, Y.C. Korean Institute of Intelligent Systems 2002 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.2 No.1

        We study some properties of smooth uniform spaces. We investigate the relationship between smooth topological spaces and smooth uniform spaces. In particular, we define a subspace of a smooth uniform space and a product of smooth uniform spaces.

      • KCI등재

        Supra fuzzy convergence of fuzzy filters

        A. A. Ramadan,A. A. Abd El-latif 대한수학회 2008 대한수학회보 Vol.45 No.2

        We introduce and study the notions of supra fuzzy conver-gence of fuzzy lters,sγ-fuzzy open (closed) sets,sγ(sγ*)-fuzzy continu-ous and sγ-fuzzy open mapping. Also, we investigate some of fundamentalproperties of these notions.

      • KCI등재

        Smooth Ideals

        Ramadan, A.A.,Kim, Y.C.,EI-Gayyar, M.K. Korean Institute of Intelligent Systems 2002 한국지능시스템학회논문지 Vol.12 No.1

        In this paper, we show that there exists a one-to-one correspondence between the collection of generalized ideals on a set and the collection of smooth ideals on a set. We study some properties of the images and preimages of smooth ideals. Smooth ideals, Generalized ideals, Images and preimages of smooth ideals.

      • KCI등재

        Cytokeratin 13, Cytokeratin 17, and Ki-67 Expression in Human Acquired Cholesteatoma and Their Correlation With Its Destructive Capacity

        Mahmood A. Hamed,Seiichi Nakata,Kazuya Shiogama,Kenji Suzuki,Ramadan H. Sayed,Yoichi Nishimura,Noboru Iwata,Kouhei Sakurai,Badawy S. Badawy,Ken-ichi Inada,Hayato Tsuge,Yutaka Tsutsumi 대한이비인후과학회 2017 Clinical and Experimental Otorhinolaryngology Vol.10 No.3

        Objectives. Cholesteatoma is a nonneoplastic destructive lesion of the temporal bone with debated pathogenesis and bone resorptive mechanism. Both molecular and cellular events chiefly master its activity. Continued research is necessary to clarify factors related to its aggressiveness. We aimed to investigate the expression of Ki-67, cytokeratin 13 (CK13) and cytokeratin 17 (CK17) in acquired nonrecurrent human cholesteatoma and correlate them with its bone destructive capacity. Methods. A prospective quantitative immunohistochemical study was carried out using fresh acquired cholesteatoma tissues (n=19), collected during cholesteatoma surgery. Deep meatal skin tissues from the same patients were used as control (n=8). Cholesteatoma patients were divided into 2 groups and compared (invasive and noninvasive) according to a grading score for bone resorption based upon clinical, radiologic and intraoperative findings. To our knowledge, the role of CK17 in cholesteatoma aggressiveness was first investigated in this paper. Results. Both Ki-67 and CK17 were significantly overexpressed in cholesteatoma than control tissues (P<0.001 for both Ki-67 and CK17). In addition, Ki-67 and CK17 were significantly higher in the invasive group than noninvasive group of cholesteatoma (P=0.029, P=0.033, respectively). Furthermore, Ki-67 and CK17 showed a moderate positive correlation with bone erosion scores (r=0.547, P=0.015 and r=0.588, P=0.008, respectively). In terms of CK13, no significant difference was found between cholesteatoma and skin (P=0.766). Conclusion. Both Ki-67 and CK17 were overexpressed in cholesteatoma tissue and positively correlated with bone resorption activity. The concept that Ki-67 can be a predictor for aggressiveness of cholesteatoma was supported. In addition, this is the first study demonstrating CK17 as a favoring marker in the aggressiveness of acquired cholesteatoma.

      • KCI등재

        Pathogenesis and Bone Resorption in Acquired Cholesteatoma: Current Knowledge and Future Prospectives

        Mahmood A. Hamed,Seiichi Nakata,Ramadan H. Sayed,Hiromi Ueda,Badawy S. Badawy,Yoichi Nishimura,Takuro Kojima,Noboru Iwata,Ahmed R. Ahmed,Khalid Dahy,Naoki Kondo,Kenji Suzuki 대한이비인후과학회 2016 Clinical and Experimental Otorhinolaryngology Vol.9 No.4

        Cholesteatoma is a cystic non tumorous lesion of the temporal bone that has the ability to destroy nearby structures by its power to cause bone resorption and as a result, fatal complications prevail. We aimed to conduct a comprehensive review for pathogenesis of acquired cholesteatoma, bone resorption mechanisms, and offer a future vision of this serious disease. We have reviewed different theories for pathogenesis of acquired cholesteatoma including the most relevant and updated ones with special emphasis on the mechanisms of bone resorption through Medline/PubMed research using the keywords ‘aetiopathogenesis, bone resorption, acquired cholesteatoma, temporal bone, and cytokines.’ In order to strengthen our study, we searched the reference lists of identified reviews. Cholesteatoma is a subject of debate among otolaryngologists since it was prescribed firstly. Over many decades, several theories were postulated for aetiopathogenesis of cholesteatoma with a tendency to follow more than one theory to explain the proper nature of that disease. Until now, the mechanism of bone resorption has yet to be more clarified. In the last century, a leap has occurred in the field of biomolecular cholesteatoma research which improved our knowledge about its pathophysiology and bone destructive mechanism. However, surgery is still the only available treatment. We conclude that discovery of new therapeutic choices for cholesteatoma other than surgery by the use of anti-growth, anti-proliferative, apoptotic agents as well as medications that antagonize osteoclastogenesis should be the main concern in the future clinical and experimental research work. Also, searching for predictors of the aggressiveness of cholesteatoma can affect the timing of intervention and prevent occurrence of complications.

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