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      • KCI등재

        Allelic variance among ABO blood group genotypes in a population from the western region of Saudi Arabia

        Abdularahman B.O. Mohamed,Salwa Ibrahim Hindawi,Sameer Al-harthi,Qamre Alam,Mohammad Zubair Alam,Absarul Haque,Waseem Ahmad,Ghazi A Damanhouri 대한혈액학회 2016 Blood Research Vol.51 No.4

        BackgroundCharacterization of the ABO blood group at the phenotype and genotype levels is clinically essential for transfusion, forensics, and population studies. This study elucidated ABO phenotypes and genotypes, and performed an evaluation of their distribution in in-dividuals from the western region of Saudi Arabia.MethodsOne-hundred and seven samples underwent standard serological techniques for ABO blood group phenotype analysis. ABO alleles and genotypes were identified using multi-plex polymerase chain reaction, and electrophoretic analysis was performed to evaluate the highly polymorphic ABO locus.ResultsA phenotype distribution of 37.4%, 30.8%, 24.3%, and 7.5% was found for blood groups O, A, B, and AB respectively in our study cohort. Genotype analysis identified 10 genotype combinations with the O01/O02 and A102/O02 genotypes being the most frequent with frequencies of 33.6% and 14.95%, respectively. Common genotypes such as A101/A101, A101/A102, A101/B101, B101/B101, and O01/O01 were not detected. Similarly, the rare genotypes, cis-AB01/O02, cis-AB01/O01, and cis-AB01/A102 were not found in our cohort. The most frequently observed allele was O02 (35.98%) followed by the A102 allele (17.76%). Furthermore, our findings are discussed in reference to ABO allele and geno-type frequencies found in other ethnic groups.ConclusionThe study has a significant implication on the management of blood bank and transfusion services in Saudi Arabian patients.

      • 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

        A comparative study of mechanical behavior of ABS material based on UVC sterilization for medical usage

        Mohamed A. Aboamer,Doaa H. Elgohary,Ali Abdullah Almukil,Ahmed A. Aboamer,Ibrahim M Alarifi,Mohsen Bakouri,Nader A. Rahman Mohamed 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.7

        This study aims to examine the mechanical properties of acrylonitrile butadiene styrene specimens using ASTM 638, 695, and 790. UVC radiation was also used as a sterilizing method. The fused deposition modeling of 3D-printed polymerize with 30 % filling was used to manufacture 30 specimens for tensile, compression, and bending. Half of the specimens were treated with UVC, whereas the other half were not. The chosen dosage of 13.5 J/cm 2 with an exposure time of 48 min corresponds to 3650 sterilization treatments or 10 years of sterilization. The average ultimate stress in the tensile test, compression test, and bending test was 34.5 ± 7.4, 25.4 ± 0.5, and 24.5 ± 2.1 Mpa, respectively. The analysis of variance test shows that UVC radiation has a demonstrable influence on tensile specimens, with a P-value of 0.012, which is less than the significance threshold of 0.05. Thus, the null hypothesis is rejected.

      • SCISCIESCOPUS

        Electrocatalytic behavior of a nanocomposite of Ni/Pd supported by carbonized PVA nanofibers towards formic acid, ethanol and urea oxidation: A physicochemical and electro-analysis study

        Mohamed, Ibrahim M.A.,Yasin, Ahmed S.,Barakat, Nasser A.M.,Song, Seung A.,Lee, Ha Eun,Kim, Seong Su Elsevier BV * North-Holland 2018 Applied Surface Science Vol.435 No.-

        <P><B>Abstract</B></P> <P>A nanocomposite of Ni/Pd supported by carbonized poly-vinyl alcohol (PVA) nanofibers (NFs) was synthesized via electrospinning followed by calcination under an argon atmosphere. The as-synthesized NFs were studied using physicochemical analyses, such as field-emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), to investigate the morphology, crystallinity, effect of carbonization and surface chemistry of the NFs, respectively. Cyclic voltammetry (CV) and chronoamperometry (CA) were utilized to study the performance of the NFs towards electrooxidation reactions. The designed NFs present superior electrocatalytic behavior in an acid medium towards formic acid oxidation, as well as urea and ethanol oxidation in an alkaline medium. The electrocatalytic performance of the bimetallic NFs appears to arise from the assembly of bimetallic Ni/Pd@NFs based on PVA, which has hydroxyl groups. These hydroxyl groups can decrease the negative processes that occur as a result of metal-metal interactions, such as the aggregation process. This study introduces a novel non-precious electrocatalyst to facilitate the commercialization of fuel cells based on formic acid, urea and ethanol.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ni&Pd@C-nanofibers are synthesized via facile two steps; electrospinning followed by carbonization. </LI> <LI> The produced NFs have FCC-crystals with crystal size and d-spacing 18.08 and 0.211 nm, respectively. </LI> <LI> Enhancement on the produced current was observed as increase of formic acid concentration up to 3 mol/l. </LI> <LI> Cyclic voltammetry studies confirm the electrocatalytic performance of the synthesized-NFs towards ethanol and urea in alkaline medium. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

      • KCI등재

        Lucerne transient streak virus; a Recently Detected Virus Infecting Alfafa (Medicago sativa) in Central Saudi Arabia

        Ahmed Raza,Ibrahim M. Al-Shahwan,Omer A. Abdalla,Mohammed A. AL-Saleh,Mahmoud A. Amer 한국식물병리학회 2017 Plant Pathology Journal Vol.33 No.1

        A survey was conducted to determine the status ofLucerne transient streak virus (LTSV) in three highyieldingalfalfa regions in central Saudi Arabia (Riyadh,Qassim, and Hail) during 2014. Three hundredand eight symptomatic alfalfa, and seven Sonchus oleraceussamples were collected. DAS-ELISA indicatedthat 59 of these samples were positive to LTSV. Twoisolates of LTSV from each region were selected formolecular studies. RT-PCR confirmed the presence ofLTSV in the selected samples using a specific primerpair. Percentage identity and homology tree comparisonsrevealed that all Saudi isolates were more closelyrelated to each other but also closely related to the Canadianisolate-JQ782213 (97.1–97.6%) and the NewZealand isolate-U31286 (95.8–97.1%). ComparingSaudi isolates of LTSV with ten other sobemovirusesbased on the coat protein gene sequences confirmedthe distant relationship between them. Eleven out offourteen plant species used in host range study werepositive to LTSV. This is the first time to documentthat Trifolium alexandrinum, Nicotiana occidentalis,Chenopodium glaucum, and Lathyrus sativus are newhost plant species for LTSV and that N. occidentalisbeing a good propagative host for it.

      • KCI등재

        Effectiveness of sequence-related amplified polymorphism (SRAP) markers to assess the geographical origin and genetic diversity of collected lentil genotypes

        Mohammed Nabil A.,Afzal Muhammad,Al-Faifi Sulieman A.,Khan Muhammad A.,Refay Yahya A.,AL-Samin Bazel H.,Alghamdi Salem S.,Ibrahim Abdullah 한국식물생명공학회 2023 Plant biotechnology reports Vol.17 No.4

        Lentil is an important annual food legume crop, nitrogen fixer and provides a substantial amount of protein, carbohydrate, minerals, and vitamin content. The use of molecular markers to assess genetic diversity is crucial for crop improvement, efficient management, and conservation of plant genetic resources. The current study aimed to determine the genetic diversity among lentil genotypes using sequence-related amplified polymorphism (SRAP) markers. Therefore, we evaluated a collection of 36 lentil genotypes, including 20 from Yemen, Saudi Arabia (7), Egypt (4), and Bangladesh (3), and (2) genotypes from the International Center for Research in Dry Area (ICARDA) using 21 SRAP primer combinations. The amplified fragments showed a high level of useful polymorphic amplified fragments (775 out of 782) indicating a higher degree of variation. The polymorphic information content (PIC) ranged from 0.31 to 0.39 with an average of 0.33 for each primer. The UPGMA trees, based on Jaccard similarity index matrices, separated the genotypes into four main clusters according to their geographical origin. The population structure supported the major groups and attested to their great degree of differentiation. The highest lentil population was found at K = 3, K = 5, and K = 7 levels, showing purity and admixture ancestry among the lentil population. This study highlighted the wide genetic diversity among the studied lentil genotypes and demonstrated the effectiveness of the SRAP technique in determining the genetic variability of lentil. Furthermore, it could be used to establish the genetic peculiarity of ecotypes when applying for the obtainment of origin and agro-morphological characteristics.

      • KCI등재

        Swertiamarin ameliorates inflammation and oxidative damage in autoimmune encephalomyelitis mouse model

        Ibrahim Hairul-Islam Mohamed,Ahmed Emad A.,Alzahrani Abdullah M.,Sayed Abdullah A.,Hanieh Hamza 한국응용생명화학회 2022 Applied Biological Chemistry (Appl Biol Chem) Vol.65 No.2

        Multiple sclerosis (MS) is a degenerative autoimmune disease attacks the myelin sheath of the central nervous system (CNS) neurons causing different disabilities. According to recent evidence, the main bioactive component in Enicostema axillare , the Swrtiamarin (SM) has been found to exert anti-inflammatory and antioxidant activities against several diseases. However, SM activities in treatment of autoimmune diseases remain to be explored. Herein, we used a murine model of MS, to show that SM treatment ameliorates the severity of experimental autoimmune encephalomyelitis (EAE). This occurs through reducing the levels of pro-inflammatory cytokines and infiltration of CD4+CD45+ cells into CNS. That was associated with a reduction in the expression of STAT3 and NFkB in CD4+ T cells under Th17 and LPS-stimulated macrophages. Furthermore, in silico studies revealed that SM interacts with NF-E2-related factor 2 (NRF2), and therefore, suppressed oxidative stress by inducing formation NRF2-antioxidant response element (ARE) complex. We found that SM is an agonist of NRF2 complex regulating the total CD4 population and antioxidant markers in EAE mice. Molecular docking analysis showed a stable and higher binding affinity between SM and NRF2. Results revealed that SM treatment increased the complex formation between ARE and NRF2 where immunoprecipitation methods showed a higher binding affinity of ARE to NRF2 in SM treated animals. Complex formation triggered ARE cascade of antioxidant gene clusters and reduces the MS pathological alterations in EAE mice model. Current data proposed SM as an effective biomolecule in treatment of MS and controlling neuronal damage through inhibiting oxidative stress markers and targeting NRF2.

      • SCIEKCI등재

        Lucerne transient streak virus; a Recently Detected Virus Infecting Alfafa (Medicago sativa) in Central Saudi Arabia

        Raza, Ahmed,Al-Shahwan, Ibrahim M.,Abdalla, Omer A.,Al-Saleh, Mohammed A.,Amer, Mahmoud A. The Korean Society of Plant Pathology 2017 Plant Pathology Journal Vol.33 No.1

        A survey was conducted to determine the status of Lucerne transient streak virus (LTSV) in three high-yielding alfalfa regions in central Saudi Arabia (Riyadh, Qassim, and Hail) during 2014. Three hundred and eight symptomatic alfalfa, and seven Sonchus oleraceus samples were collected. DAS-ELISA indicated that 59 of these samples were positive to LTSV. Two isolates of LTSV from each region were selected for molecular studies. RT-PCR confirmed the presence of LTSV in the selected samples using a specific primer pair. Percentage identity and homology tree comparisons revealed that all Saudi isolates were more closely related to each other but also closely related to the Canadian isolate-JQ782213 (97.1-97.6%) and the New Zealand isolate-U31286 (95.8-97.1%). Comparing Saudi isolates of LTSV with ten other sobemoviruses based on the coat protein gene sequences confirmed the distant relationship between them. Eleven out of fourteen plant species used in host range study were positive to LTSV. This is the first time to document that Trifolium alexandrinum, Nicotiana occidentalis, Chenopodium glaucum, and Lathyrus sativus are new host plant species for LTSV and that N. occidentalis being a good propagative host for it.

      • Dynamic analysis of piezoelectric perforated cantilever bimorph energy harvester via finite element analysis

        Yousef A. Alessi,Ibrahim Ali,Mashhour A. Alazwari,Khalid Almitani,Alaa A Abdelrahman,Mohamed A. Eltaher Techno-Press 2023 Advances in aircraft and spacecraft science Vol.10 No.2

        This article presents a numerical analysis to investigate the natural frequencies and harmonic response of a perforated cantilever beam attached to two layers of piezoelectric materials by using the finite element method for the first time. The bimorph piezoelectric is composed of 3 layers; two of them at the outer are piezoelectric, and the inner isotropic material. A higher order 3-D 20-node solid element that exhibits quadratic displacement behavior is exploited to discretize the isotropic layer, and coupled piezoelectric 3D element with twenty nodes is used to mesh the top and bottom layers. CIRCU94 element is added to act as a resistor part of the model. The proposed model is validated with previous works. The numerical parametric studies are presented to illustrate the effects of perforation geometry, the number of rows, the resistance on the natural frequencies, frequency response, and power. It is found that the thickness has a positive relationship with the natural frequency. Perforations help in producing higher voltage, and the best shape is rectangular perforations, and to produce higher voltage, two rows of rectangular perforations should be applied.

      • KCI등재

        Sub-switching domain effect for analysis the non-linear dielectric behavior of (K0.49 Na0.49Li0.02) (Nb0.98Sb0.02)O3 ceramic based on Rayleigh model

        Atito Ibrahim A.,Shaban H. T.,Salem A.,Ezzeldien Mohammed,Mahmoud Abd El-razek 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.5

        The solid-state sintering technique has been implemented to synthesize (K 0.5 Na 0.5 NbO 3 )-0.02(LiSbO 3 ) (KNN-LS) Pb- free ceramic. The crystal structure, dielectric and ferroelectric properties of the prepared material were investigated. Pure orthorhombic perovskite phase [ I (220) / I (002) = 1.68] with Amm2 space group has been detected at room temperature for sintered ceramic. Two anomalous permittivity peaks corresponding to orthorhombic–tetragonal (O–T) phase transition at T = 175 °C and tetragonal–cubic (T–C) phase transition at T = 355 °C have been observed. At polymorphic phase transition, the Ray- leigh model shown the extrinsic contributions caused by domain wall motion is about 80%, while the intrinsic contribution attributed to the lattice distortion is about 20%. Ferroelectric properties were investigated in a wide range of temperatures (RT-225)°C. The results shown a conductive material at high temperature due to the higher cation disorder and leakage cur- rent above PPT. The present results are interested for understanding the mechanism of t permittivity–temperature behavior of KNN-doped LS ions based on Rayleigh model. The large remnant polarization and low coercive fi eld below PPT make the material a suitable candidate for energy storage application.

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