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      • KCI등재

        Synthesis, Pharmacological Activity Evaluation and Molecular Modeling of New Polynuclear Heterocyclic Compounds Containing Benzimidazole Derivatives

        Fatma A. Bassyouni,Tamer S. Saleh,Mahmoud M. ElHefnawi,Sherein I. Abd El-Moez,Waled M. El-Senousy,Mohamed E. Abdel-Rehim 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.12

        Novel heterocyclic compounds containing benzimidazole derivatives were synthesized from 2-(1Hbenzimidazol-2-yl) acetonitrile (1) and arylhydrazononitrile derivative 2 was obtained via coupling of 1 with 4-methyl phenyldiazonium salt, which was then reacted with hydroxylamine hydrochloride to give amidooxime derivative 3. This product was cyclized into the corresponding oxadiazole derivative 4 upon reflux in acetic anhydride. Compound 4 was refluxed in DMF in the presence of triethylamine to give the corresponding 5-(1H-benzimidazol-2-yl)-2-p-tolyl-2H-1,2,3-triazol-4-amine 6. Treatment of compound 6 with ethyl chloroformate afforded 2,6-dihydro-2-(4-methylphenyl)-1,2,3-triazolo[4'',5''-4',5']pyrimido[1,6-a]benzimidazole-5(4H)-one (8). 1,2-bis(2-cyanomethyl-1H-benzimidazol-1-yl)ethane-1,2-dione (10) was synthesized via the condensation reaction of 2-(1H-benzimidazol-2-yl) acetonitrile (1) and diethyloxalate. The reactivity of compound 10 towards some diamine reagents was studied. The in vitro antimicrobial activity of the synthesized compounds was investigated against several pathogenic bacterial strains such as Escherichia coli O157, Salmonella typhimurium, E. coli O119, S. paratyphi, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus. The results of MIC revealed that compounds 12a-c showed the most effective antimicrobial activity against tested strains. On the other hand, compounds 12a, b exhibited high activity against rotavirus Wa strain while compounds 12b, c exhibited high activity against adenovirus type 7. In silico target prediction, docking and validation of the compounds 12a-c were performed. The dialkylglycine decarboxylase bacterial enzyme was predicted as a potential bacterial target receptor using pharmacophorebased correspondence with previous leads; giving the highest normalized scores and a high correlation docking score with mean inhibition concentrations. A novel binding mechanism was predicted after docking using the MOE software and its validation.

      • KCI등재

        Physical characterization and radiation shielding features of B2O3-As2O3 glass ceramic

        Mohamed Y. Hanfi,Ahmed K. Sakr,A.M. Ismail,Bahig M. Atia,Mohammed S. Alqahtani,K.A. Mahmoud 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.1

        The synthetic B2O3eAs2O3 glass ceramic are prepared to investigate the physical properties and the radiation shielding capabilities with the variation of concentration of the As2O3 with 10, 20, 30, and 40%, respectively. XRD analyses are performed on the fabricated glasseceramic and depicted the improvement of crystallinity by adding As2O3. The radiation shielding properties are studied for the B2O3eAs2O3 glass ceramic. The values of linear attenuation coefficient (LAC) are varied with the variation of incident photon gamma energy (23.1e103 keV). The LAC values enhanced from 12.19 cm1e37.75 cm1 by raising the As2O3 concentration from 10 to 40 mol% at low gamma energy (23.1 keV) for BAs10 and BAs40, respectively. Among the shielding parameters, the halfevalue layer, transmission factor, and radiation protection efficiency are estimated. Furthermore, the fabricated samples of glass ceramic have low manufacturing costs and good shielding features compared to the previous work. It can be concluded the B2O3eAs2O3 glass ceramic is appropriate to apply in X-ray or low-energy gamma-ray shielding applications.

      • SCIESCOPUS

        An incremental convex programming model of the elastic frictional contact problems

        Mohamed, S.A.,Helal, M.M.,Mahmoud, F.F. Techno-Press 2006 Structural Engineering and Mechanics, An Int'l Jou Vol.23 No.4

        A new incremental finite element model is developed to simulate the frictional contact of elastic bodies. The incremental convex programming method is exploited, in the framework of finite element approach, to recast the variational inequality principle of contact problem in a discretized form. The non-classical friction model of Oden and Pires is adopted, however, the friction effect is represented by an equivalent non-linear stiffness rather than additional constraints. Different parametric studies are worked out to address the versatility of the proposed model.

      • SCIESCOPUSKCI등재

        The radiation shielding competence and imaging spectroscopic based studies of Iron ore region of Kozhikode district, Kerala

        S. Arivazhagan,K.A. Naseer,K.A. Mahmoud,S.A. Bassam,P.N. Naseef Mohammed,N.K. Libeesh,A.S. Sachana,M.I. Sayyed,Mohammed S. Alqahtani,E. El Shiekh,Mayeen Uddin Khandaker Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.7

        Hyperspectral data and its ability to explore the minerals and their associated rocks have a remarkable application in mineral exploration and lithological characterization. The present study aims to explore the radiation shielding aspects of the iron ore in Kerala with the aid of the Hyperion hyperspectral dataset. The reflectance-spectra obtained from the laboratory conditions as well as from the image show various absorptions. The results from the spectra are validated with geochemical data and GPS points. The Monte Carlo simulation employed to evaluate the radiation shielding ability. Raising the oxygen ions caused a noteworthy decrease in the µ values of the studied rocks which is accompanied by an increase in Δ<sub>0.5</sub> and Δ<sub>eq</sub> values. The Δ<sub>0.5</sub> and Δ<sub>eq</sub> values increased by factors of approximately 77 % with raising the oxygen ions between 44.32 and 47.57 wt.%. The µ values varies with the oxygen concentrations, where the µ values decreased from 2.531 to 0.925 cm<sup>-1</sup> (at 0.059 MeV), from 0.381to 0.215 cm<sup>-1</sup> (at 0.662 MeV), and from 0.279 to 0.158 cm<sup>-1</sup> (at 1.25 MeV) with raising the oxygen ions from 44.32 to 47.43 wt.%.

      • KCI등재

        Optimizing Pumping Rate in Pipe Networks Supplied by Groundwater Sources

        Mohamed M. Somaida,Medhat M. H. El-Zahar,Yasser A. Hamed,Mahmoud S. Sharaan 대한토목학회 2013 KSCE JOURNAL OF CIVIL ENGINEERING Vol.17 No.5

        In the present paper, an analytical solution has been reached for determining the optimum pumping rate in a pipe network supplied from a ground water source by means of water wells. The solution depends on the use of the gradient technique which requires the derivatives of the studied cost functions and is based on the maximum economic benefit from the produced water. The solution is examined on a predetermined optimal water distribution system, and gives values for optimum pumping rates which are in good agreement with those obtained using the graphical solutions, indicating the reliability of the analytical solution. The effect of the initial cost on the optimum pumping rate and its bearing on the unit price of water has been also studied. This reflects the importance of choosing the proper unit water price that makes the water return covers the global cost and satisfies the maximum economic benefit from the produced water. Studying the effect of unit price of water on the water return or different pumping rates shows that,whether ignoring or including the initial cost, the water return increases with increase of pumping rate till reaching a turning point,often which the water return begin to drop slightly. Hence, this point determines the optimum pumping rate in the pipe network as well as the maximum economic benefit satisfied. Finally within the scope of the present study, it is concluded that, the identity or good agreement found in the results of optimum pumping rates, indicates the validity of the developed analytical solution and the employed graphical solutions.

      • KCI등재

        Metabolic Effects of Honey in Type 1 Diabetes Mellitus: A Randomized Crossover Pilot Study

        Mamdouh M. Abdulrhman,Mohamed H. El-Hefnawy,Rasha H. Aly,Rania H. Shatla,Rasha M. Mamdouh,Doaa M. Mahmoud,Waheed S. Mohamed 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.1

        The aim of this study was to evaluate the metabolic effects of 12-week honey consumption on patients suffering from type 1 diabetes mellitus (DM). This was a randomized crossover clinical trial done in the National Institute for Diabetes and Endocrinology, Cairo, Egypt. Twenty patients of both sexes aged 4–18 years with type 1 DM and HbA1C<10% participated in the study. They were randomized into two equal groups (intervention to control and control to intervention). The dietary intervention was 12-week honey consumption in a dose of 0.5 mL/kg body weight per day. The main outcome measures were serum glucose, lipids, and C-peptide, and anthropometric measurements. None of participants were lost in follow-up. The intervention resulted in significant decreases in subscapular skin fold thickness (SSFT; P=.002), fasting serum glucose (FSG; P=.001), total cholesterol (P=.0001), serum triglycerides (TG; P=.0001), and low-density lipoprotein (P=.0009), and significant increases in fasting C-peptide (FCP; P=.0004) and 2-h postprandial C-peptide (PCP; P=.002). As possible long-term effects of honey after its withdrawal, statistically significant reductions in midarm circumference (P=.000), triceps skin fold thickness (P=.006), SSFT (P=.003), FSG (P=.005), 2-h postprandial serum glucose (P=.000), TG (P=.003), and HbA1C (P=.043), and significant increases in FCP (P=.002) and PCP (P=.003) were observed. This small clinical trial suggests that long-term consumption of honey might have positive effects on the metabolic derangements of type 1 DM.

      • Impacts of surface irregularity on vibration analysis of single-walled carbon nanotubes based on Donnell thin shell theory

        Selim, Mahmoud M.,Althobaiti, Saad,Yahia, I.S.,Mohammed, Ibtisam M.O.,Hussin, Amira M.,Mohamed, Abdel-Baset A. Techno-Press 2022 Advances in nano research Vol.12 No.5

        The present work is an attempt to study the vibration analysis of the single-walled carbon nanotubes (SWCNTs) under the effect of the surface irregularity using Donnell's model. The surface irregularity represented by the parabolic form. According to Donnell's model and three-dimensional elasticity theory, a novel governing equations and its solution are derived and matched with the case of no irregularity effects. To understand the reaction of the nanotube to the irregularity effects in terms of natural frequency, the numerical calculations are done. The results obtained could provide a better representation of the vibration behavior of an irregular single-walled carbon nanotube, where the aspect ratio (L/d) and surface irregularity all have a significant impact on the natural frequency of vibrating SWCNTs. Furthermore, the findings of surface irregularity effects on vibration SWCNT can be utilized to forecast and prevent the phenomena of resonance of single-walled carbon nanotubes.

      • Serum Talin-1 is a Potential Novel Biomarker for Diagnosis of Hepatocellular Carcinoma in Egyptian Patients

        Youns, Mahmoud M.,Abdel Wahab, Abdel Hady A.,Hassan, Zeinab A.,Attia, Mohamed S. Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

        Background: Hepatocellular carcinoma (HCC) is a major cause of cancer mortality worldwide. The outcome of HCC depends mainly on its early diagnosis. To date, the performance of traditional biomarkers is unsatisfactory. Talins were firstly identified as cytoplasmic protein partners of integrins but Talin-1 appears to play a crucial role in cancer formation and progression. Our study was conducted to assess the diagnostic value of serum Talin-1 (TLN1) compared to the most feasible traditional biomarker alpha-fetoprotein (AFP) for the diagnosis of HCC. Methods: TLN1 was detected using enzyme linked immunosorbent assay (ELISA) in serum samples from 120 Egyptian subjects including 40 with HCC, 40 with liver cirrhosis (LC) and 40 healthy controls (HC). Results: ROC curve analysis was used to create a predictive model for TLN1 relative to AFP in HCC diagnosis. Serum levels of TLN1 in hepatocellular carcinoma patients were significantly higher compared to the other groups (p<0.0001). The diagnostic accuracy of TLN1 was higher than that of AFP regarding sensitivity, specificity, positive predictive value and negative predictive value in diagnosis of HCC. Conclusions: The present study showed for the first time that Talin-1 (TLN1) is a potential diagnostic marker for HCC, with a higher sensitivity and specificity compared to the traditional biomarker AFP.

      • KCI등재

        The radiation shielding proficiency and hyperspectral-based spatial distribution of lateritic terrain mapping in Irikkur block, Kannur, Kerala

        Arivazhagan S.,Naseer K.A.,Mahmoud K.A.,Libeesh N.K.,Arun Kumar K.V.,Naga Kumar K.ChV.,Sayyed M.I.,Alqahtani Mohammed S.,Shiekh E. El,Khandaker Mayeen Uddin 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.9

        The practice of identifying the potential zones for mineral exploration in a speedy and low-cost method includes the use of satellite imagery analysis as a part of remote sensing techniques. It is challenging to explore the iron mineralization of a region through conventional methods which are a time-consuming process. The current study utilizes the Hyperion satellite imagery for mapping the iron mineralization and associated geological features in the Irikkur region, Kannur, Kerala. Along with the remote sensing results, the field study and laboratory-based analysis were conducted to retrieve the ground truth point and geochemical proportion to verify the iron ore mineralization. The MC simulation showed for shielding properties indicate an increase in the linear attenuation coefficient with raising the Fe2O3þSiO2 concentrations in the investigated rocks where it is varied at 0.662 MeV in the range 0.190 cm1 - 0.222 cm1 with rising the Fe2O3þSiO2 content from 57.86 wt% to 71.15 wt%. The analysis also revealed that when the g-ray energy increased from 0.221 MeV to 2.506 MeV, sample 1 had the largest linear attenuation coefficient, ranging from 9.33 cm1 to 0.12 cm1 . Charnockite rocks were found to have exceptional shielding qualities, making them an excellent natural choice for radiation shielding applications.

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