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121.
Samia E. Omer Tawasol M. Ibrahim Omer A. Krar Amna M. Ali Alaa A. Makki Walaa Ibraheem Abdulrahim A. Alzain 《Biochemistry and Biophysics Reports》2022
The current novel corona virus illness (COVID-19) is a developing viral disease that was discovered in 2019. There is currently no viable therapeutic strategy for this illness management. Because traditional medication development and discovery has lagged behind the threat of emerging and re-emerging illnesses like Ebola, MERS-CoV, and, more recently, SARS-CoV-2. Drug developers began to consider drug repurposing (or repositioning) as a viable option to the more traditional drug development method. The goal of drug repurposing is to uncover new uses for an approved or investigational medicine that aren't related to its original use. The main benefits of this strategy are that there is less developmental risk and that it takes less time because the safety and pharmacologic requirements are met. The main protease (Mpro) of corona viruses is one of the well-studied and appealing therapeutic targets. As a result, the current research examines the molecular docking of Mpro (PDB ID: 5R81) conjugated repurposed drugs. 12,432 approved drugs were collected from ChEMBL and drugbank libraries, and docked separately into the receptor grid created on 5R81, using the three phases of molecular docking including high throughput virtual screening (HTVS), standard precision (SP), and extra precision (XP). Based on docking scores and MM-GBSA binding free energy calculation, top three drugs (kanamycin, sulfinalol and carvedilol) were chosen for further analyses for molecular dynamic simulations. 相似文献
122.
The side population (SP) phenotype has been reported as a method to identify hematopoietic stem cells in the bone marrow based upon differential staining with the fluorescent dye, Hoechst 33342. This technique has drawn great interest in the stem cell community, as it may provide a simple approach to the enrichment of progenitor cells from a variety of normal and malignant tissues. The frequency of these cells and their performance in functional assays has varied considerably within the literature. To investigate mechanisms that may contribute to the SP phenotype, we measured the fluorescence emission of Hoechst-stained bone marrow cells as a function of both time and dye concentration using a custom flow cytometer and data acquisition software. These measurements demonstrate that all nucleated cells within the bone marrow undergo an identical staining pattern at varying rates, even under conditions previously reported to abrogate the SP. Therefore, the SP phenotype is not unique to stem cells, but rather represents a transient feature of marrow cells exposed to Hoechst 33342 for varying amounts of time. We propose that heterogeneity of SP-defined populations may be a consequence of the rate at which differing cell populations accumulate Hoechst 33342. Further, we suggest that dye uptake kinetics will likely be an important factor for optimal use of Hoechst 33342 in isolating stem cells. 相似文献
123.
124.
Y chromosome lineage- and village-specific genes on chromosomes 1p22 and 6q27 control visceral leishmaniasis in Sudan
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Miller EN Fadl M Mohamed HS Elzein A Jamieson SE Cordell HJ Peacock CS Fakiola M Raju M Khalil EA Elhassan A Musa AM Ibrahim ME Blackwell JM 《PLoS genetics》2007,3(5):e71
Familial clustering and ethnic differences suggest that visceral leishmaniasis caused by Leishmania donovani is under genetic control. A recent genome scan provided evidence for a major susceptibility gene on Chromosome 22q12 in the Aringa ethnic group in Sudan. We now report a genome-wide scan using 69 families with 173 affected relatives from two villages occupied by the related Masalit ethnic group. A primary ten-centimorgan scan followed by refined mapping provided evidence for major loci at 1p22 (LOD score 5.65; nominal p = 1.72 × 10−7; empirical p < 1 × 10−5; λS = 5.1) and 6q27 (LOD score 3.74; nominal p = 1.68 × 10−5; empirical p < 1 × 10−4; λS = 2.3) that were Y chromosome–lineage and village-specific. Neither village supported a visceral leishmaniasis susceptibility gene on 22q12. The results suggest strong lineage-specific genes due to founder effect and consanguinity in these recently immigrant populations. These chance events in ethnically uniform African populations provide a powerful resource in the search for genes and mechanisms that regulate this complex disease. 相似文献
125.
Heba A. Ahmed Eman H. S. Ibrahim Ekram Abdelhaliem Eman Y. T. Elariny 《Journal of applied microbiology》2022,132(6):4555-4568
The aim of this study was to investigate the frequency, molecular characterization, virulence genes, resistance genes and antimicrobial profile of nosocomial extended spectrum beta lactamase producing Klebsiella species. A total of 22 (12.2%) K. pneumoniae strains were isolated from 180 clinical samples collected from hospitalized patients in Egypt. K. pneumoniae biotypes were B1 (72.8%), B3 (13.6%) and B4 (13.6%). The isolates were classified for the capsular serotypes, 86.4% (20/22) were of K1 serotype, while only two isolates (13.64%) were of K2 serotype. Hypermucoviscous K. pneumoniae isolates accounted for 68.2%. Biofilm formation ability of K. pneumoniae was determined by microtitre plate method. The majority of the isolates (40.9%) were moderate biofilm producers, while 27.3% were strong biofilm producers. All K. pneumoniae strains were positive for fimH and traT genes, while magA was identified in only 63.6% of the isolates. The antibiotic susceptibility profile of the isolates (n = 22) was determined by the disc diffusion technique using 23 different antibiotics. Streptomycin and imipenem are the most effective antibiotics against 22 tested K. pneumoniae isolates with sensitivity rates of 63.64% and 54.54% respectively. All tested K. pneumoniae isolates showed high resistance to amoxicillin∕clavulanate (100%), cefuroxime (100%) and ceftazidime (95.45%). Extended spectrum beta lactamases (ESBL) production and the presence of ESBL-related genes were tested in the isolates. All the isolates tested positive for blaVIM, NDM1 and blaTEM, while only 81.8 %tested positive for the blaSHV gene. Increasing antimicrobial resistance in K. pneumoniae causing nosocomial infections limits the use of antimicrobial agents for treatment. Furthermore, the spread of biofilm, multiple drug resistant and ESBL-producing K. pneumoniae isolates is a public threat for hospitalized patients. 相似文献
126.
Ibrahim M. El-Deen El-Zend Manar A. Tantawy Mohamed A. Barakat Lamiaa A. A. 《Russian Journal of Bioorganic Chemistry》2022,48(2):380-390
Russian Journal of Bioorganic Chemistry - A series of coumarin and aza-coumarin derivatives (II–IX) were synthesized and identified using IR, 1H NMR, and 13C NMR spectral data. All the... 相似文献
127.
Faraag Ahmed Hassan Ibrahim Shafaa Medhat W. Elkholy Nourhan S. AbdelHafez Lina Jamil M. 《International microbiology》2022,25(3):663-663
International Microbiology - 相似文献
128.
Erin G. Roberts Vladimir F. Kleptsyn Gregory D. Roberts Katherine J. Mossburg Bei Feng Ibrahim J. Domian Sitaram M. Emani Joyce Y. Wong 《Biotechnology and bioengineering》2019,116(11):3098-3111
Here we propose a bio-MEMS device designed to evaluate contractile force and conduction velocity of cell sheets in response to mechanical and electrical stimulation of the cell source as it grows to form a cellular sheet. Moreover, the design allows for the incorporation of patient-specific data and cell sources. An optimized device would allow cell sheets to be cultured, characterized, and conditioned to be compatible with a specific patient's cardiac environment in vitro, before implantation. This design draws upon existing methods in the literature but makes an important advance by combining the mechanical and electrical stimulation into a single system for optimized cell sheet growth. The device has been designed to achieve cellular alignment, electrical stimulation, mechanical stimulation, conduction velocity readout, contraction force readout, and eventually cell sheet release. The platform is a set of comb electrical contacts consisting of three-dimensional walls made of polydimethylsiloxane and coated with electrically conductive metals on the tops of the walls. Not only do the walls serve as a method for stimulating cells that are attached to the top, but their geometry is tailored such that they are flexible enough to be bent by the cells and used to measure force. The platform can be stretched via a linear actuator setup, allowing for simultaneous electrical and mechanical stimulation that can be derived from patient-specific clinical data. 相似文献
129.
Gregor Schlüter Arzu Celik Renato Obata Mike Schlicker Sigrun Hofferbert Astrid Schlung Ibrahim M. Adham Wolfgang Engel 《Molecular reproduction and development》1996,43(1):1-6
Structural data are presented on the protamine gene cluster (PGC) of human, mouse, rat, and bull. By restriction mapping we demonstrate that the organization of the protamine cluster is conserved throughout all four species, i.e., the genes are situated in a head to tail arrangement in the order: protamine l-protamine 2-transition protein 2. Further, we established the nucleotide sequence of the entire human PGC (25 kb in total) and the 3′ portion of the rat protamine cluster (PRM2 and TNP2 genes and intergenic region). In addition, a 1 kb fragment of the bovine and murine protamine cluster, situated between PRM2 and TNP2, was sequenced. This fragment is conserved regarding sequence, position, and orientation in all species examined, and was classified as likely coding region by gene recognition program GRAIL. Using the rat fragment as a probe in RNA blots, we detected a testis-specific signal of about 0.5 kb. Finally, we demonstrate a high density of Alu elements, both full and fragmented copies, in the human PGC and discuss their localization with respect to evolutionary and functional aspects. © 1996 Wiley-Liss, Inc. 相似文献
130.