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41.
Peerzada Yasir Yousuf Altaf Ahmad Ibrahim M. Aref Munir Ozturk Hemant Arshid Hussain Ganie Muhammad Iqbal 《Protoplasma》2016,253(6):1565-1575
Brassica juncea is mainly cultivated in the arid and semi-arid regions of India where its production is significantly affected by soil salinity. Adequate knowledge of the mechanisms underlying the salt tolerance at sub-cellular levels must aid in developing the salt-tolerant plants. A proper functioning of chloroplasts under salinity conditions is highly desirable to maintain crop productivity. The adaptive molecular mechanisms offered by plants at the chloroplast level to cope with salinity stress must be a prime target in developing the salt-tolerant plants. In the present study, we have analyzed differential expression of chloroplast proteins in two Brassica juncea genotypes, Pusa Agrani (salt-sensitive) and CS-54 (salt-tolerant), under the effect of sodium chloride. The chloroplast proteins were isolated and resolved using 2DE, which facilitated identification and quantification of 12 proteins that differed in expression in the salt-tolerant and salt-sensitive genotypes. The identified proteins were related to a variety of chloroplast-associated molecular processes, including oxygen-evolving process, PS I and PS II functioning, Calvin cycle and redox homeostasis. Expression analysis of genes encoding differentially expressed proteins through real time PCR supported our findings with proteomic analysis. The study indicates that modulating the expression of chloroplast proteins associated with stabilization of photosystems and oxidative defence plays imperative roles in adaptation to salt stress. 相似文献
42.
Ibrahim A. Al-Suwaidan Alaa A.-M. Abdel-Aziz Taghreed Z. Shawer Rezk R. Ayyad Amer M. Alanazi Ahmad M. El-Morsy 《Journal of enzyme inhibition and medicinal chemistry》2016,31(1):78-89
A novel series of 3-benzyl-substituted-4(3H)-quinazolinones were designed, synthesized and evaluated for their in vitro antitumor activity. The results of this study demonstrated that 2-(3-benzyl-6-methyl-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)acetamide, 2-(3-benzyl-6,7-dimethoxy-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)acetamide and 3-(3-benzyl-6-methyl-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)-propanamide have shown amazing broad spectrum antitumor activity with mean GI50 (10.47, 7.24 and 14.12?µM. respectively), and are nearly 1.5–3.0-fold more potent compared with the positive control 5-FU with mean GI50, 22.60?µM. On the other hand, compounds 6 and 10 yielded selective activities toward CNS, renal and breast cancer cell lines, whereas compound 9 showed selective activities towards leukemia cell lines. Molecular docking methodology was performed for compounds 7 and 8 into ATP binding site of EGFR-TK which showed similar binding mode to erlotinib, while compound 11 into ATP binding site of B-RAF kinase inhibited the growth of melanoma cell lines through inhibition of B-RAF kinase, similar to PLX4032. 相似文献
43.
Al‐Sayed Al‐Soudy Tsuyoshi Nakanishi Seiya Mizuno Yoshikazu Hasegawa Hossam H. Shawki Megumi C. Katoh Walaa A. Basha Abdelaziz E. Ibrahim Hany A. El‐Shemy Hiroyoshi Iseki Atsushi Yoshiki Youhei Hiromori Hisamitsu Nagase Satoru Takahashi Hisashi Oishi Fumihiro Sugiyama 《Genesis (New York, N.Y. : 2000)》2016,54(7):389-397
Spermatogenesis is a complex and highly regulated process by which spermatogonial stem cells differentiate into spermatozoa. To better understand the molecular mechanisms of the process, the Cre/loxP system has been widely utilized for conditional gene knockout in mice. In this study, we generated a transgenic mouse line that expresses Cre recombinase under the control of the 2.5 kbp of the Prolactin family 3, subfamily b, member 1 (Prl3b1) gene promoter (Prl3b1‐cre). Prl3b1 was initially reported to code for placental lactogen 2 (PL‐2) protein in placenta along with increased expression toward the end of pregnancy. PL‐2 was found to be expressed in germ cells in the testis, especially in spermatocytes. To analyze the specificity and efficiency of Cre recombinase activity in Prl3b1‐cre mice, the mice were mated with reporter R26GRR mice, which express GFP ubiquitously before and tdsRed exclusively after Cre recombination. The systemic examination of Prl3b1‐cre;R26GRR mice revealed that tdsRed‐positive cells were detected only in the testis and epididymis. Fluorescence imaging of Prl3b1‐cre;R26GRR testes suggested that Cre‐mediated recombination took place in the germ cells with approximately 74% efficiency determined by in vitro fertilization. In conclusion, our results suggest that the Prl3b1‐cre mice line provides a unique resource to understand testicular germ‐cell development. genesis 54:389–397, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
44.
Farhani Ibrahim Nezafat Navid Mahmoodi Shirin 《International journal of peptide research and therapeutics》2019,25(2):541-553
International Journal of Peptide Research and Therapeutics - Shigella spp. causes severe diarrhea and dysenteric disease, which known as shigellosis. Until now, no licensed vaccine is available for... 相似文献
45.
Raza Zulfiqar Ali Tariq Muhammad Rizwan Majeed Muhammad Irfan Banat Ibrahim M. 《Bioprocess and biosystems engineering》2019,42(6):901-919
Bioprocess and Biosystems Engineering - Polyhydroxyalkanoates (PHAs) are biological plastics that are sustainable alternative to synthetic ones. Numerous microorganisms have been identified as PHAs... 相似文献
46.
Haseeb A. Khan Salman Alamery Khalid E. Ibrahim Doaa M. El-Nagar Najla Al-Harbi Mohamad Rusop Salman H. Alrokayan 《Saudi Journal of Biological Sciences》2019,26(3):625-631
Gold nanoparticles (GNPs) are among the ideal nano-sized materials for medical applications such as imaging and drug delivery. Considering the significance of recent reports on acute phase induction of inflammatory mediators by GNPs, we studied the effect of GNPs on proinflammatory cytokines gene expression in mouse brain. Group 1 served as control whereas groups 2–4 were given only one intraperitoneal dose of 5, 20 and 50?nm GNPs, respectively and sacrificed after 24?h. The animals in groups 5–7 also received the same treatment but sacrificed after 7?days. Groups 8–10 received two injections of GNPs (5, 20 and 50?nm, respectively), first at the beginning of study and second on day 6, and sacrificed on day 7. Total RNA was extracted from the cerebral tissue and analyzed for the gene expressions of IL-1β, IL-6 and TNF-α. A single injection of 5?nm diameter GNPs significantly increased the mRNA expression of IL-1β and IL-6 in mouse brain on day 7, which was not augmented by the second dose of the same GNPs. Larger size GNPs (20?nm and 50?nm) did not cause any significant change in the expression of proinflammatory cytokines in mouse brain. In conclusion, systemic administration of small sized GNPs (5?nm) induced a proinflammatory cascade in mouse brain indicating a crucial role of GNPs size on immune response. It is important to use the right sized GNPs in order to avoid an acute phase inflammatory response that could be cytotoxic or interfere with the bioavailability of nanomaterials. 相似文献
47.
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
48.
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
49.
Anvarhusein A. Isab Ibrahim H. Ghazi Mohammed I. M. Wazeer Herman P. Perzanowski 《Journal of inorganic biochemistry》1993,50(4):299-304
15N NMR studies of the interaction of 15N cyanide ion with gold(I)-thiomalate (Autm) and gold(I)-thioglucose (Autg) have been carried out at pH* 7.40. The chemical shifts of the two 15N ions containing species Au(C15N)2− and RS-Au-C15N− (where RS− = tm− or tg−) were identified at 265.94 and 260.30 ppm, respectively. From the broadened 15N NMR signals, approximate life times of the RS-Au-CN− species were calculated. 相似文献
50.
Effects of dietary soybean lecithin on plasma lipid transport and hepatic cholesterol metabolism in rats 总被引:3,自引:0,他引:3
LeBlanc MJ Brunet S Bouchard G Lamireau T Yousef IM Gavino V Lévy E Tuchweber B 《The Journal of nutritional biochemistry》2003,14(1):40-48
Dietary lecithin can stimulate bile formation and biliary lipid secretion, particularly cholesterol output in bile. Studies also suggested that the lecithin-rich diet might modify hepatic cholesterol homeostasis and lipoprotein metabolism. Therefore, we examined hepatic activities of 3-hydroxy-3 methylglutaryl coenzyme A reductase "HMG -CoA reductase", cholesterol 7 alpha-hydroxylase and acyl-CoA: cholesterol acyltransferase "ACAT" as well as plasma lipids and lipoprotein composition in rats fed diets enriched with 20% of soybean lecithin during 14 days. We also evaluated the content of hepatic canalicular membrane proteins involved in lipid transport to the bile (all P-glycoproteins as detected by the C 219 antibody and the sister of P-glycoprotein "spgp" or bile acid export pump) by Western blotting. As predicted, lecithin diet modified hepatic cholesterol homeostasis. The activity of hepatic HMG-CoA reductase and cholesterol 7 alpha-hydroxylase was enhanced by 30 and 12% respectively, while microsomal ACAT activity showed a dramatic decrease of 75%. As previously reported from ACAT inhibition, the plasma level and size of very low-density lipoprotein (VLDL) were significantly decreased and bile acid pool size and biliary lipid output were significantly increased. The canalicular membrane content of lipid transporters was not significantly affected by dietary lecithin. The current data on inhibition of ACAT activity and related metabolic effects by lecithin mimic the previously reported effects following drug-induced inhibition of ACAT activity, suggesting potential beneficial effects of dietary lecithin supplementation in vascular disease. 相似文献