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1.
Protoplasma - Watermelon and melon are members of the Cucurbitaceae family including economically significant crops in the world. The expansin protein family, which is one of the members of the...  相似文献   
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In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1H-NMR, 13C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f .  相似文献   
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Yilmaz  Şehnaz  Yoldas  Oguz  Dumani  Aysin  Guler  Gizem  Ilgaz  Seda  Akbal  Eylül  Oksuz  Hale  Celik  Ayla  Yilmaz  Bertan 《Molecular biology reports》2020,47(7):5377-5383
Molecular Biology Reports - Antimicrobial irrigation solutions are widely used under clinical settings. Their effect on dental tissue is a subject of recent research, which aims for a safer...  相似文献   
4.
Integrin CD11b/CD18 is a key adhesion receptor that mediates leukocyte migration and immune functions. Leukadherin-1 (LA1) is a small molecule agonist that enhances CD11b/CD18-dependent cell adhesion to its ligand ICAM-1. Here, we used single-molecule force spectroscopy to investigate the biophysical mechanism by which LA1-activated CD11b/CD18 mediates leukocyte adhesion. Between the two distinct populations of CD11b/CD18:ICAM-1 complex that participate in cell adhesion, the cytoskeleton(CSK)-anchored elastic elements and the membrane tethers, we found that LA1 enhanced binding of CD11b/CD18 on K562 cells to ICAM-1 via the formation of long membrane tethers, whereas Mn2+ additionally increased ICAM-1 binding via CSK-anchored bonds. LA1 activated wild-type and LFA1−/− neutrophils also showed longer detachment distances and time from ICAM-1-coated atomic force microscopy tips, but significantly lower detachment force, as compared to the Mn2+-activated cells, confirming that LA1 primarily increased membrane-tether bonds to enhance CD11b/CD18:ICAM-1 binding, whereas Mn2+ induced additional CSK-anchored bond formation. The results suggest that the two types of agonists differentially activate integrins and couple them to the cellular machinery, providing what we feel are new insights into signal mechanotransduction by such agents.  相似文献   
5.
A bioassay-guided phytochemical analysis of the triterpene saponins from under ground parts of Gypsophila arrostii var. nebulosa allowed the isolation of two triterpene saponins; nebuloside A, B based on gypsogenin and quillaic acid aglycone. Two new oleanane type triterpenoid saponins (nebuloside A, B) and three known saponins (13) were isolated from the root bark of Gypsophila arrostii var. nebulosa. The structures of the two new compounds were elucidated as 3-O-β-d-galactopyranosyl-(1→2)-[β-d-xylopyranosyl-(1→3)]-β-d-glucuronopyranosyl quillaic acid 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside A) and 3-O-β-d-xylopyranosyl-(1→3)-[β-d-galactopyranosyl(1→3)-β-d-galactopyranosyl-(1→2)]-β-d-glucuronopyranosyl gypsogenin 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside B), on the basis of extensive spectral analysis and chemical evidence. Nebuloside A and B showed toxicity enhancing properties on saporin a type-I RIP without causing toxicity by themselves at 15 μg/mL.  相似文献   
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CLTOAB is an ammonium-based ionic liquid composed of ε-Caprolactam (CL) C6H11NO and tetraoctylammonium bromide (TOAB) (C32H68BrN). In this study, experimental IR and Raman spectra of CLTOAB ionic liquid together with the computational results of the compound have been reported. The optimized geometry, vibrational frequencies, IR intensities and Raman activities of the CLTOAB were calculated using the wb97xd and B3LYP density functional methods combined with the 6-31G(d,p) basis set using Gaussian 03 program. The complete assignment of the bands was performed based on the potential energy distributions (PED%). The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. The Gauge-including atomic orbital 1H-NMR and 13C-NMR chemical shifts calculations were carried out and compared with the experimental data. Furthermore to evaluate interaction between CLTOAB and DNA, molecular docking study was carried out.

Communicated by Ramaswamy H. Sarma  相似文献   

9.
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   
10.
Nigella sativa (NS) has been shown to have antioxidant and antiinflammatory activities in different conditions. The goal of this study was to evaluate the effects of NS on cholestatic liver injury in rats. Thirty rats were recruited in the study as follows: Group 1, Bile duct ligation (BDL) (n = 10); Group 2, BDL plus NS (n = 10); and Group 3, Sham (n = 10). Bile duct ligated group received 0.2 mL kg?1 dose of NS intraperitoneally daily throughout 14 days. Liver damage and cholestasis were determined by the biochemical and the pathologic examination. Data showed a decrease in gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities of the NS treated rats when compared with BDL group (p < 0.001 for GGT and p < 0.05 for others). The NS treated rats' tissue levels of total oxidant status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) were significantly lower than that of the BDL group (p < 0.01 for all). Increases in total antioxidant capacity (TAC) and catalase (CAT) levels were statistically significant in the NS treated rats compared to BDL group (p < 0.01 for both). On the other hand, administration of NS in the rats with biliary obstruction resulted in inhibition of necro‐inflammation. These results indicate that NS exerts a therapeutic effect on cholestatic liver injury in bile duct ligated rats possibly through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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