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231.
Salem Zeinab A. Kamel Amany Hany Mohamed AbuBakr Nermeen 《Journal of molecular histology》2021,52(3):467-477
Journal of Molecular Histology - Diabetes mellitus (DM) is one of the major metabolic diseases. Xerostomia and salivary gland dysfunction are of its common oral complications. Exosomes, as a new... 相似文献
232.
Zeinab Tavassoli 《Journal of biomolecular structure & dynamics》2018,36(1):166-176
One way to control hypertension is inactivation of the Renin- Angiotensin- Aldosterone System (RAAS). Inhibition of renin as a rate-limiting step of this system is an effective way to stop up RAAS. It has been proved that soyasaponin I, an herbal compound obtained from soybeans, has anti-hypertensive effect via renin inhibition, so it has the potential of being an anti-hypertensive drug. Herein, some theoretical approaches such as Docking Simulation, Molecular Dynamics (MD) Simulation and MMPBSA analysis have been used to study how soyasaponin I inhibits renin at the structural level. The results of docking simulation and hydrogen bond pattern show that this ligand is able to bind to the active site of renin and a region near the active site. Results of MD simulation for renin – soyasaponin I complexes confirm that soyasaponin I binds to the active site of renin and has inhibition effect on it via competing with the substrate. Besides, according to MMPBSA analysis, the binding free energy for renin – soyasaponin I complex is ?42.61 kcal/mol when it binds to the active site. Comparing to the peptide obtained from angiotensinogen, ΔG = ?74.96 kcal/mol, it may inferred that although binding of soyasaponin I to the active site of renin does not have a complete competition with the substrate, it might attenuate the formation of renin – angiotensinogen complex and have partial non-competitive effect. The results of this survey might be helpful to design partial non – competitive renin inhibitors with pharmaceutical capability. 相似文献
233.
Louisa Roudini Negar NayebZadeh Eidgahi Hamid Reza Rahimi Mohammad Reza Saberi Zeinab Amiri Tehranizadeh Sima Beigoli 《Journal of biomolecular structure & dynamics》2020,38(2):364-381
AbstractThe binding of small molecules with histone-DNA complexes can cause an interference in vital cellular processes such as cell division and the growth of cancerous cells that results in apoptosis. It is significant to study the interaction of small molecules with histone-DNA complex for the purpose of better understanding their mechanism of action, as well as designing novel and more effective drug compounds. The fluorescence quenching of ct-DNA upon interaction with Berberine has determined the binding of Berberine to ct-DNA with Ksv?=?9.46?×?107 M?1. Ksv value of ct-DNA-Berberine in the presence of H1 has been observed to be 3.10?×?107 M?1, indicating that the H1 has caused a reduction in the binding affinity of Berberine to ct-DNA. In the competitive emission spectrum, ethidium bromide (EB) and acridine orange (AO) have been examined as intercalators through the addition of Berberine to ct-DNA complexes, which includes ctDNA-EB and ctDNA-AO. Although in the presence of histone H1 , we have observed signs of competition through the induced changes within the emission spectra, yet there has been apparently no competition between the ligands and probes. The viscosity results have confirmed the different behaviors of interaction between ctDNA and Berberine throughout the binary and ternary systems. We have figured out the IC50 and viability percent values at three different time durations of interaction between Berberine and MCF7 cell line. The molecular experiments have been completed by achieving the results of MTT assay, which have been confirmed to be in good agreement with molecular modeling studies.Communicated by Ramaswamy H. Sarma 相似文献
234.
Zeinab Mamouei Shakti Singh Bernard Lemire Yiyou Gu Abdullah Alqarihi Sunna Nabeela Dongmei Li Ashraf Ibrahim Priya Uppuluri 《PLoS biology》2021,19(3)
A forward genetic screening approach identified orf19.2500 as a gene controlling Candida albicans biofilm dispersal and biofilm detachment. Three-dimensional (3D) protein modeling and bioinformatics revealed that orf19.2500 is a conserved mitochondrial protein, structurally similar to, but functionally diverged from, the squalene/phytoene synthases family. The C. albicans orf19.2500 is distinguished by 3 evolutionarily acquired stretches of amino acid inserts, absent from all other eukaryotes except a small number of ascomycete fungi. Biochemical assays showed that orf19.2500 is required for the assembly and activity of the NADH ubiquinone oxidoreductase Complex I (CI) of the respiratory electron transport chain (ETC) and was thereby named NDU1. NDU1 is essential for respiration and growth on alternative carbon sources, important for immune evasion, required for virulence in a mouse model of hematogenously disseminated candidiasis, and for potentiating resistance to antifungal drugs. Our study is the first report on a protein that sets the Candida-like fungi phylogenetically apart from all other eukaryotes, based solely on evolutionary “gain” of new amino acid inserts that are also the functional hub of the protein. 相似文献
235.
Zeinab F. Mahmoud N.A.Abdel Salam Taha M. Sarg Ferdinand Bohlmann 《Phytochemistry》1981,20(4):735-738
The aerial parts of Inula crithmoides afforded a new carotane derivative and a eudesmanolide, inucrithmolide. The most probable structures were elucidated by the spectroscopic data and by some chemical transformations. 相似文献
236.
Ibrahim F. Nassar Ahmed F. El Farargy Fathy M. Abdelrazek Zeinab Hamza 《Nucleosides, nucleotides & nucleic acids》2020,39(7):991-1010
Abstract6-(4-Chloro-3-nitrophenyl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile (4) was prepared and was reacted with ethyl chloroacetate, hydrazine hydrate, 4-chloroaniline, formaldehyde, acetic anhydride, formic acid, carbon disulfide, 4-cyanobenzaldehyde, triethyl orthoformate, D-sugars, 4-aminoacetophenone, benzoyl choride and cyclohexanone to afford a series of new uracil derivatives (5–18). Examination of some of the prepared compounds for their antimicrobial, antioxidant and anticancer activities was conducted. Among the tested samples, compound 17 was the most active substance against the gram-positive bacteria and was more potent than the reference drug Cefoperazone. Moreover, the antibacterial activity of 17 was higher against gram-negative bacteria. Compounds 6 and 13 reached a higher scavenging ability toward DPPH radicals and are better candidates for antioxidant activity. Also, compounds 6 and 13 had no significant anticancer activity toward liver cancer (Hep G2) and breast cancer (MCF-7) cell lines. 相似文献
237.
Herbicide tolerance in maize is related to increased levels of glutathione and glutathione-associated enzymes 总被引:1,自引:0,他引:1
Mamdouh M. Nemat Alla Abdel-Hakeem M. Badawi Nemat M. Hassan Zeinab M. El-Bastawisy Enas G. Badran 《Acta Physiologiae Plantarum》2008,30(3):371-379
Treatment of 10 days old maize seedlings with metribuzin and pretilachlor near the recommended field-dose resulted in differential
reductions in shoot fresh and dry weights during the following 16 days. Metribuzin showed great and consistent reductions,
however, the reduction induced by pretilachlor, mostly nullified by the end of the experiment. Moreover, there were differential
accumulations of lipid peroxides, carbonyl groups and H2O2 in maize leaves; metribuzin caused the greatest accumulation. Meanwhile, levels of thiol forms and reduced glutathione (GSH)
were much more induced by pretilachlor than metribuzin; the contrary was true regarding oxidized glutathione (GSSG). The ratio
of GSH/GSSG was highest following pretilachlor treatment and least by metribuzin. On the other hand, activities of glutathione-S-transferases (GSTs, EC 2.5.1.18), γ-glutamyl-cysteine synthetase (γ-GCS, EC 6.3.2.2), glutathione synthetase (GS, EC 6.3.2.3),
glutathione peroxidase (GPX, EC 1.15.1.1) and glutathione reductase (GR, EC 1.6.4.2) were more enhanced in maize leaves by
pretilachlor than metribuzin. These findings suggest the occurrence of an oxidative stress differentially induced in maize
by the herbicides, a state that was most pronounced with metribuzin. Pretilachlor was concluded to be the least phytotoxic
to maize, while metribuzin was the most, this differential tolerance seemed to be related to the induction of GSH and GSH-associated
enzymes. 相似文献
238.
Summary The mineral nutrition ofEchinops spinosissimus Turra on white calcareous dune, loamy soil and gravel sandy soil, representing the habitats of the plant in the semi-desert
and desert, has been studied. In all cases Ca content in the plant generally exceeded K or Na. Better nutritional conditions
occurred on the loamy soil where K, Na, and Mg nearly reached half the level of Ca in the plant. Weak nutrition was observed
on the white-dune and gravel-sand soils. Early competition for minerals seems not so excessive being, moreover, readily accentuated
through natural thinning of seedlings. The nutritional problem under such habitats has been discussed. 相似文献
239.
240.
Sajad Hassanzadeh Maryam Jalessi Seyed Behnamedin Jameie Mehdi Khanmohammadi Zohre Bagher Zeinab Namjoo Seyed Mohammad Davachi 《Biochemistry and Biophysics Reports》2021
Functional improvement after spinal cord injury remains an unsolved difficulty. Glial scars, a major component of SCI lesions, are very effective in improving the rate of this recovery. Such scars are a result of complex interaction mechanisms involving three major cells, namely, astrocytes, oligodendrocytes, and microglia. In recent years, scientists have identified two subtypes of reactive astrocytes, namely, A1 astrocytes that induce the rapid death of neurons and oligodendrocytes, and A2 astrocytes that promote neuronal survival. Moreover, recent studies have suggested that the macrophage polarization state is more of a continuum between M1 and M2 macrophages. M1 macrophages that encourage the inflammation process kill their surrounding cells and inhibit cellular proliferation. In contrast, M2 macrophages promote cell proliferation, tissue growth, and regeneration. Furthermore, the ability of oligodendrocyte precursor cells to differentiate into adult oligodendrocytes or even neurons has been reviewed. Here, we first scrutinize recent findings on glial cell subtypes and their beneficial or detrimental effects after spinal cord injury. Second, we discuss how we may be able to help the functional recovery process after injury. 相似文献