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Mohamed, M. S., S. F. Sabet, M. M. Moustafa, and M. S. Salama, "Correlation between a Single Nucleotide Polymorphism (G/T at nt", African Journal of Biotechnology, 2011. Abstract

Interferon used in the treatment of hepatitis C virus (HCV) patients stimulates the expression of a number of host genes encoding enzymes with antiviral activities, including myxovirus resistance gene-1 (Mx1). Mx1 gene was found to have a single nucleotide polymorphism (SNP) at position -88 in the promotor region that affect the expression of Mx 1 protein and was suggested to be associated with the response of HCV. In this study, we assessed the relation between the SNP in the Mx1 gene and the responsiveness of Egyptian HCV patients to pegylated interferon and ribavirin treatment along with other host-related and virus-related predictors of treatment outcome. We genotyped the biallelic G/T SNP in the promoter region of Mx1 gene at position -88 from the transcription start site by restriction fragment length polymorphism found that Mx1 nt-88 SNP is not significantly correlated to achieving sustained virological response (SVR) after pegylated interferon alpha and ribavirin combined treatment.

Fekry, A. M., and R. H. Tammam, "Corrosion and Impedance Studies on Magnesium Alloy in Oxalate Solution", Materials Science and Engineering B, vol. 176, issue 10, pp. 792-798, 2011. AbstractCU-PDF.pdf

Corrosion behavior of AZ91E alloy was investigated in oxalate solution using potentiodynamic polarization and electrochemical impedance measurements (EIS). The effect of oxalate concentration was studied, where the corrosion rate increases with increasing oxalate concentration. The effect of added ions (Br-, Cl- or SiO ) on the electrochemical behavior of magnesium alloy in 0.1 M Na2C2O4 solution at 298 K, was investigated. It was found that the corrosion rate of 0.1 M oxalate solution containing silicate ion is lower than the blank (0.1 M Na2C2O4). This was confirmed by scanning electron microscope (SEM) observations. However, for the other added ions Br- or Cl-, the corrosion rate is higher than the blank. Keywords: AZ91E; Oxalate; EIS; Polarization; SEM.

El-Moneim, A. A., E. Akiyama, K. M. Ismail, and K. Hashimoto, "Corrosion Behaviour of Sputter-Deposited Mg", Corrosion Science, vol. 53, issue 9, pp. 2988–2993, 2011. CU-PDF.pdf
Ameer, M. A., and A. M. Fekry, "Corrosion Inhibition of Mild Steel by Natural Product Compound", Journal Progress in Organic Coating, vol. 71, pp. 343-349, 2011. AbstractCU-PDF.pdf

Corrosion inhibition of mild steel in H3PO4 containing chloride or sulphate ions have been studied using different electrochemical techniques. The corrosion and hydrogen evolution of mild steel alloy in 2M H3PO4 acid containing 0.5M NaCl can be effectively inhibited by addition of natural product compound, Thymol (IPMP), of different concentrations. However, in 2M H3PO4 containing 0.5M Na2SO4 corrosion cannot be effectively inhibited. The results of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements confirm the synergistic effects which describe the increase in the effectiveness of a corrosion inhibitor in the presence of Cl? ions in the corrosive medium. At any temperature, an increase in it leads to an increase of the corrosion rate and hydrogen evolution on mild steel. Polarization and EIS results are in good agreement with each other. The obtained results were confirmed by surface examination using scanning electron.

Atta, N. F., A. M. Fekry, and H. M. Hassaneen, "Corrosion Inhibition, Hydrogen Evolution and Antibacterial Properties of Newly Synthesized Organic Inhibitors on 316L Stainless Steel Alloy in Acid Medium", International Journal of Hydrogen Energy, vol. 36, issue 11, pp. 6462–6471, 2011. AbstractCU-PDF.pdf


S.M.M.Shanab, M. A.Ameer, A. M. Fekry, A. A. Ghoneim, and E. A. Shalaby, "Corrosion Resistance of Magnesium Alloy (AZ31E) asOrthopaedic Biomaterials in Sodium Chloride ContainingAntioxidantly Active Compounds from Eichhornia crassipes", Int. J. Electrochem. Sci., 2011. Abstract

Eichhornia crassipes (Water hyacinth) is a hydrophyte which invaded all Egyptian water bodies causing serious problems of navigation and water quality deterioration. Known weight of the sample was successively extracted with hexane (E1), ethyl acetate (E2) and methanol ( E3). Antioxidant activity of extracts was performed by two complementary test system , 2.2'diphenyl-1- picryl hydrazyl (DPPH) and 2,2'- azino-bis (ethylbenzthiazoline-6- sulfonic acid (ABTS) methods which revealed the highest activity of E3 followed in descending order by E2 and E1. Fractionation of the promising methanol extract E3, produced five antioxidantly active fractions (a-e). Identification of the five fractions was performed using chromatographic and spectroscopic methods. Electrochemical impedance spectroscopy (EIS) experiments were carried out in artificial sea water (3.5% NaCl) to study the corrosion inhibition effect of Eichhornia crassipes (Water hyacinth) extracts (E1, E2, E3) and E3 fractions (a-e) on extruded AZ31E

Fahmy, S. R., and S. A. H. Hamdi, "Curative Effect of the Egyptian Marine Erugosquilla massavensis Extract on Carbon Tetrachloride-Induced Oxidative Stress in Rat Liver and Erythrocytes", European Review for Medical and Pharmacological Sciences, vol. 15, issue 3, pp. 303-12., 2011. AbstractCU-PDF.pdf

The purpose of the present work was to investigate the effect of marine crustacean extract (MCE) from marine mantis shrimp Erugosquilla massavensis and silymarin on oxidative stress induced by carbon tetrachloride (CCl4) in rat liver and erythrocytes.
Male rats were randomly divided into 3 main groups, (1) control group which administered olive oil orally for 2 days, followed by distilled water for 7 consecutive days, (2) MCE group in which rats administered orally MCE, 250 mg/kg body weight for 9 consecutive days and (3) CCl4-treated group in which rats given CCl4 orally (2.5 ml/kg body weight) for 2 days. This group then subdivided into 5 subgroups. All subgroups treated orally for 7 consecutive days with distilled water (subgroup I), silymarin, 150 mg/kg body weight (subgroup II) and MCE at three tested doses 50, 100 and 250 mg/kg body weight (subgroups III, IV and V).
The MCE and silymarin produced significant hepatoprotective effect by decreasing the activity of serum aminotransferases (ASAT and ALAT) and alkaline phosphatase (ALP) as well as malondialdehyde (MDA) level, and increasing the serum total protein, glutathione reduced (GSH) levels and the activities of glutathione-S-transferase (GST) and catalase (CAT). The MCE and silymarin also showed the same antioxidant effect on erythrocytes.
The results of the present study, suggested that, the MCE could protect the liver and erythrocytes injuries perhaps, by its antioxidative effect, hence eliminating the deleterious effect of toxic metabolites from CCl4.

Elmegeed, G. A., W. K. B. Khalil, R. M. Mohareb, H. H. Ahmed, M. M. Abd-Elhalim, and G. H. Elsayed, "Cytotoxicity and Gene Expression Profiles of Novel Synthesized Steroid Derivatives as Chemotherapeutic Anti-Breast Cancer Agents", Bioorganic and Medicinal Chemistry, vol. 19, issue 22, pp. 6860–6872, 2011. CU-PDF.pdf
Soliman, M. S. A., A. K. Hegazy, S. K. Goda, M. H. Emam, and A. A. Al-Atar, "Cytotoxicity and Mutagenic Effects of Soil Radionuclides on Some Black Sand Plant Species", Journal of Mediterranean Ecology, vol. 11, pp. 5-20, 2011. AbstractCU-PDF.pdf

Three plant species (CakilemaritimaScop., Senecioglaucus L. and RumexpictusForssk) were selected from three blacksand habitats along the Mediterranean coast in Egypt for cytogenetic studies and to recognizes the mechanism by whichplants withstand high concentration of the absorbed radionuclides through determination of the electrophoratic bandingpattern of protein and amino acid profiles. The study showed that exposure of the study plant species to soil radionuclidescauses decrease in the percentage of prophase and prophase to metaphase ratio, while the percentage of anaphase and telophaseincreases with soil radioactivity. The results revealed chromosomal aberrations, e.g., C-metaphase, star metaphase,chromosome stickiness at metaphase stage, C-anaphase and chromosomal breaks at the different mitotic stages with fluctuationin the index of mitotic phases. High radionuclide content of plants causes alterations in the bands relative mobility andintensities, expression of new proteins and suppression of some proteins.

El-Tawil, O. S., A. H. Abou-Hadeed, M. F. EL-Bab, and A. A. Shalaby, "D-Amphetamine-induced Cytotoxicity and Oxidative Stress in Isolated Rat Hepatocytes", Pathophysiology, vol. 18, issue 4, pp. 279-285, 2011. AbstractCU-PDF.pdf

Amphetamines (AMP) are potent psychostimulants and commonly used drugs of abuse. Its chronic administration creates tolerance and addiction and also associated with neurotoxicity and hepatocellular damage through oxidative stress.

Shams, H. Z., R. M. Mohareb, and M. H. H. E. - S. andAmira Mahmoud, "Design and Synthesis of Novel Antimicrobial Acyclic and Heterocyclic Dyes and Their Precursors for Dyeing and/or Textile Finishing Based on 2- N -Acylamino-4,5,6,7-tetrahydro-benzo[ b]thiophene Systems", Molecules, vol. 16, pp. 6271-6305, 2011. AbstractCU-PDF.pdf

A series of novel polyfunctionalized acyclic and heterocyclic dye precursors andtheir respective azo (hydrazone) counterpart dyes and dye precursors based on conjugateenaminones and/or enaminonitrile moieties were synthesized. The dyes and their precursorsare based on 2-cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide,2-ethoxycarbonyl-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)

SA., Marouf, K. F. Mohamed, J., and E. L. - J. akee, "Detection of Mycoplasma bovis and Mycoplasma bovigenitalium in Cattle andBuffalo in Egypt Using Dot ELISA and PCR with Anti -Microbial Trials", European Journal of Biological Sciences, vol. 25, pp. 136-146, 2011. AbstractCU-PDF.pdf

Mycoplasmae have the ability to colonize the respiratory and reproductive tracts of bovine. Consequently, these microorganisms can be associated with infertility and pneumonia. A total of 555 cows and 130 buffalo's samples (nasal swabs, lung tissues, tracheal swabs, bronchial lymph nodes and vaginal swabs) was collected from different Egyptian governorates and investigated. Mycoplasmaisolates collected from the respiratory tract of cattle and buffaloes were typed as M. bovis(2.7 and 1.7%, respectively) and other Mycoplasma species (10.8 and 4.2%, respectively). M. boviswas typed from vaginal swabs of the examined cows and buffaloes with incidence of 2.2 and 10 %, respectively, while the incidence of M. bovigenitaliumwas 13.3 and 10 %, respectively. Treatment of Mycoplasma diseases is difficult since Mycoplasma species lack a cell wall and are thus resistant to some commonly used antibiotics. Exposure of M. bovisand M. bovigenitaliumisolates to 1.1Ie against five antibiotics including erythromycin, gentamicin, tetracycline, streptomycin and lincomycin in comparison to reference strains revealed that lincomycin, erythromycin and streptomycin are more effective and able to get rid of M. bovisand M. bovigenitalium.

Park, J. - Y., J. - H. Choi, B. - M. Kim, J. - H. Park, S. - K. Cho, M. W. Ghafar, A. A. M. El-Aty, and J. - H. Shim, "Determination of Acetamiprid Residues in Zucchini Grown Under Greenhouse Conditions: Application to Behavioral Dynamics", Biomedical Chromatography, vol. 25, pp. 136-146, 2011. CU-PDF.pdf
Atta, N. F., A. Galal, and S. M. Azab, "Determination of morphine at gold nanoparticles/Nafion", Analyst., vol. 136, pp. 4682-4692, 2011. AbstractCU-PDF.pdf

Novel and effective electrochemical sensor for the determination of morphine (MO) in 0.04 mol L-1 universal buffer solution (pH 7.4) is introduced using gold nanoparticles electrodeposited on a Nafion modified carbon paste electrode. The effect of various experimental parameters including pH, scan rate and accumulation time on the voltammetric response of MO was investigated. At the optimum conditions, the concentration of MO was determined using differential pulse voltammetry (DPV) in a linear range of 2.0 x 10-7 to 2.6 x 10-4 mol L-1 with a correlation coefficient of 0.999, and a detection limit of 13.3 x 10-10 mol L-1, respectively. The effect of common interferences on the current response of morphine namely ascorbic acid (AA) and uric acid (UA) is studied. The modified electrode can be used for the determination of MO spiked into urine samples, and excellent recovery results were obtained.

Jeong, W. Y., J. S. Jin, Y. A. Cho, J. H. Lee, S. Park, S. W. Jeong, Y. - H. Kim, C. - S. Lim, A. A. M. El-Aty, G. - S. Kim, et al., "Determination of Polyphenols in Three Capsicum Annuum L", Journal of Separation Science, vol. 34, issue 21, pp. 2967-74, 2011. AbstractCU-PDF.pdf

A mixture of polyphenol components was isolated from the fruits of C. annuum L. cv. Cupra, C. annuum L. cv. Orange glory, and C. annuum L. cv. ST4712 (CLST), via 70% methanol extraction followed by column chromatography over silica gel. The polyphenol components of the mixture were analyzed via HPLC-MS/MS and compared with the reported data. Three cinnamic acid derivatives and five flavonoid components in the fruits of the three varieties were identified for the first time in this study. The antioxidant activity and anticancer effect of the polyphenol mixtures of the three fruits were determined. The antioxidant and anticancer activities of CLST were substantially higher than those of C. annuum L. cv. Cupra and C. annuum L. cv. Orange glory. The high activities of CLST were attributed to the much higher concentration of quercetin derivatives in CLST.

Liu, X., A. A. M. El-Aty, J. - Y. Park, J. - H. Park, S. - K. Cho, H. - C. Shin, and J. - H. Shim, "Determination of Spinetoram in Leafy Vegetable Crops using Liquid Chromatography and Confirmation via tandem mass Spectrometry", Biomedical Chromatography, vol. 25, issue 10, pp. 1099-106, 2011. AbstractCU-PDF.pdf

Spinetoram is a second-generation member of the spinosyn class, all members of which have been shown to be effective in insect control via a novel mode of action. Spinetoram is a mixture of 3'-O-ethyl-5, 6-dihydro spinosyn J (XDE-175-J) and 3'-O-ethyl spinosyn L (XDE-175-L). In order to establish a determination method for the analysis of spinetoram residues in crops, commercial product (5% suspension concentrate spinetoram) was applied to two leafy vegetables (Garland chrysanthemum and Aster scaber) on different spraying schedules. The analytical method used herein was based on a reversed-phase separation on a C(18) column, isocratic elution and UV detection. The analytes were confirmed via tandem mass spectrometry. The method was linear over a concentration range of 0.05-10 ppm with a correlation coefficient in excess of 0.9998. The recoveries of XDE-175-J and XDE-175-L from the two vegetables ranged between 86.04 and 98.87% at spiking levels of 1 and 5 ppm. The relative standard deviations were no more than 7% for all recovery tests conducted herein. The calculated limits of detection and quantification were 0.01 and 0.03 ppm for both XDE-175-J and XDE-175-L. The levels of residues in two vegetables treated under a fixed schedule in the greenhouse were 6.21-0.55 ppm (maximum residue limit (MRL) = 7 ppm). In sum, this method constitutes an easy and reliable technique for the determination of spinetoram in leafy vegetables.

Cho, H. - J., K. Jo, H. Yi, S. M. Cho, A. A. M. El-Aty, M. K. Kim, S. B. Han, J. H. Oh, C. H. Kwon, J. - H. Shim, et al., "Development and Validation of A Liquid Chromatography Method with Electrospray Ionization Tandem Mass Spectrometry for the Determination of Brotizolam Residues in Beef and Commercial Whole Milk", Biomedical Chromatography, vol. 25, issue 9, pp. 1061-6, 2011. CU-PDF.pdf
Park, J. H., M. I. R. Mamun, A. A. M. El-Aty, T. W. Na, J. - H. Choi, M. W. Ghafar, K. S. Kim, S. D. Kim, and J. - H. Shim, "Development and Validation of a multiresidue Method for Determination of 37 Pesticides in Soil using GC-NPD", Biomedical Chromatography, vol. 25, issue 9, pp. 1003–1009, 2011. Abstract

In this study, a multiresidue analytical method for the detection of 37 pesticides in a soil matrix was developed and validated. The soil sample was fortified with a known quantity of pesticides at two different concentration levels (0.1 and 0.01 µg/g) and the analytes were extracted via a liquid–solid extraction method. The pesticides were separated on an HP5 capillary column and were analyzed with a gas chromatograph coupled to a nitrogen–phosphorous detector (GC-NPD). Method validation was accomplished with good linearity (r2 = 0.994–0.999) within a considerable range of concentrations. Satisfactory recoveries (70.5–110.4%) were obtained with 32 pesticides at both spiking concentration levels, whereas five pesticides—dimepiperate, buprofezin, prometryn, pirimicarb, and fludioxonil—were recovered at relatively low levels (43.6–61.8%). The applicability of the method was demonstrated by analyzing field samples collected from 24 different sites around Yeongsan and Sumjin rivers in the Republic of Korea. No residues of the selected pesticides were detected in any of the samples. The developed method could be employed as a simple and cost-effective method for the routine detection and analysis of 37 pesticides in soil samples.

Park, J. - Y., J. - H. Choi, A. A. M. El-Aty, B. M. Kim, J. - H. Park, W. J. Choi, and J. - H. Shim, "Development and Validation of an Analytical Method for Determination of Endocrine Disruptor, 2,4-D, In Paddy Field Water", Biomedical Chromatography, vol. 25, issue 9, pp. 1018–1024, 2011. Abstract

The acidic herbicides are an important class of chemical compounds that are used to control a variety of weeds that threaten many crops. Owing to their low microbial activity levels, the acidic herbicides exhibit a residual activity remaining for periods of up to several months in soils and water. The principal objective of this study was to develop an analytical method based on liquid–liquid and solid-phase extraction followed by HPLC, for the determination of 2,4-D in paddy field water. The residues were verified via tandem mass spectrometry (MS/MS) in negative-ion electrospray ionization (ESI) mode. Linearity was good over a concentration range of 1–100 µg/L with a correlation coefficient (r2) of 0.999. The mean recovery rates of triplicate results ranged from 85.2 to 90.85%. The limits of detection and quantitation were 0.4 and 1.0 µg/L, respectively. The method proposed herein was applied to field samples acquired from Hampyung and Sunchang counties, Republic of Korea. The analyte was detected at a concentration range of 6.8–12.8 and 3.55–24.0 µg/L, respectively.

Choi, J. - H., M. I. R. Mamun, A. A. M. El-Aty, J. - H. Park, E. - H. Shin, J. Y. Park, S. - K. Cho, S. C. Shin, K. B. Lee, and J. - H. Shim, "Development of a Single-Step Precipitation Cleanup Method for the Determination of Enrofloxacin, Ciprofloxacin, and Danofloxacin in Porcine Plasma", Food Chemistry, vol. 127, issue 4, pp. 1878–1883, 2011. AbstractCU-PDF.pdf

In this study, we describe a newly developed and simple analytical method using high-performance liquid chromatography coupled to fluorescence detector (HPLC-FLD) for the determination of enrofloxacin, ciprofloxacin, and danofloxacin in porcine plasma. A single-step sample preparation, including extraction with acidic acetonitrile, coagulation with ammonium acetate, and centrifugation made possible the direct analysis of plasma samples without the need for any further cleanup procedure. The developed method was validated with specificity, linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, and precision. All results were fully adequate. In the study using porcine plasma incurring enrofloxacin, the developed method proved capable of quantifying concentrations below its maximum residue limit, and its time-course residues were excreted within the 10-day withdrawal time.

Mohareb, R. M., H. H. Ahmed, G. A. Elmegeed, M. M. Abd-Elhalim, and R. W. Shafic, "Development of New Indole-derived Neuroprotective Agents", Bioorganic & Medicinal Chemistry, vol. 19, issue 9, pp. 2966–2974, 2011. CU-PDF.pdf
Elnasharty, I. Y., A. K. Kassem, M. Sabsabi, and M. A. Harith, "Diagnosis of Lubricating Oil by Evaluating Cyanide and Carbon Molecular Emission Lines in Laser Induced Breakdown Spectra", Spectrochimica Acta, vol. 66, issue 8, pp. 588–593, 2011. AbstractCU-PDF.pdf

To prevent engine failure it is essential to change lubricating oil regularly before it loses its protective properties. It is also necessary to monitor the physical and chemical conditions of the oil to reliably determine the optimum oil-change intervals. The present work focuses on studying evolution of the cyanide (CN) and carbon (C2) molecular spectral emission lines in the laser induced breakdown spectra of lubricating oil as a function of its consumption.

Rasmy, G. E., W. K. B. Khalil, S. A. Moharib, A. A. Kawkab, and E. W. Jwanny, "Dietary Fish Oil Modulates the Effect of Dimethylhydrazine-Induced Colon Cancer in Rats", grasas y aceites, vol. 62, issue 3, pp. 253-267, 2011. AbstractCU-PDF.pdf

This study was conducted to examine the efficacy of fish oil supplementation in male wistar rat colon carcinogenesis.In order to induce colon cancer, the rats were given a weekly subcutaneous injection of 1,2-Dimethyl hydrazine (DMH) at a dose of 20 mg/kg b.w. for five weeks. Afterwards, some of the rats ingested fish oil for either 4 weeks (DMH-FO4 group), or 17 weeks (DMH-FO17 group). The remaining rats continued without any supplementation for the same 4 weeks (DMH4 group), or 17 weeks (DMH17 group). Another two groups of rats did not receive the DMH and were given fish oil (FO17 group) or a normal diet only and considered as the control group (CN group). At the end of the experiment, the rats were sacrificed; and were subsequently subjected to biochemical and molecular biological analyses as well as histopathological examinations. The results showed increased levels of lactate dehydrogenase (LDH), malondialdehyde (MDA) and alkaline phoshatase (ALP) activities in the DMH rats compared to the control. The liver and colonic changes that were induced by DMH were significantly improved through fish oil supplementation in the DMH-FO17 group. The molecular analysis revealed that DMH treatment induced the expression alterations of genes p53, p27 and p21 and increased DNA band patterns related to cancer, while both FO17 and DMH-FO17 groups showed much better results. A histopathological examination of the DMH17 group revealed colon adenocarcinoma and several lesions in rat liver tissues. An improvement in the histopathological picture was seen in the livers and colons of groups DMH- FO17. In conclusion, the present results demonstrated the anti-carciongenic effect of herring fish oil against DMH induced colon carcinogenesis in rats. The inhibitory effect ofFO was due to the modulation of elevated biochemical parameters, DNA damage and histopathological lesions caused by DMH.

El-Beltagi, H. S., A. A. Mohamed, and B. E. - D. B. Mekki, "Differences in some constituents, enzymes activity and electrophoretic characterization of different rapeseed (Brassica napus L", Analele Universit??ii din Oradea - Fascicul Biologie, issue 1, pp. 45-52, 2011. AbstractCU-PDF.pdf

Rapeseed is one of the most important oilseed crops cultivated in many parts of the world and used as a source of edible oil for human consumption. The present work reports some phytochemical and nutritional potentials of different rapeseed cultivars with a view to exploit their benefits for human nutrition. Five rapeseed cultivars namely; pactol, silvo, topas, serw 4 and serw 6 were analyzed for their phytochemical constituents (such as glutathione, ascorbate, phenolic, flavonoid contents) and some antioxidant enzymes activity (i.e. GPX; guaiacol peroxidase, APX; ascorbate peroxidase, CAT; catalase, SOD; superoxide dismutase) together with their protein profile. Among all cultivars significant variations in glutathione, ascorbate, phenolic and flavonoid contents were observed. The highest DPPH radical scavenging activity of the extract was observed in topas cultivar. Minor variations were noticed in SDS-PAGE protein profile. The results of the study suggest the phytochemical and nutritional potentials of B. napus seeds for human and other animal uses due to their extensive consumption in the world