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991.
Ilkay Orhan Berrin Özçelik Sinem Aslan Murat Kartal Taner Karaoglu Bilge Şener Salih Terzioglu M. Iqbal Choudhary 《Phytochemistry Reviews》2007,6(1):189-196
Purpose of the present study was to evaluate antioxidant, antibacterial, antifungal, and antiviral activities of the petroleum
ether, chloroform, ethyl acetate and methanol extracts as well as the alkaloid fraction of Lycopodium clavatum L. (LC) from Lycopodiaceae growing in Turkey. Antioxidant activity of the LC extracts was evaluated by 1,1-diphenyl-2-picrylhydrazyl
(DPPH) radical-scavenging method at 0.2 mg/ml using microplate-reader assay. Antiviral assessment of LC extracts was evaluated
towards the DNA virus Herpes simplex (HSV) and the RNA virus Parainfluenza (PI-3) using Madin-Darby Bovine Kidney (MDBK) and Vero cell lines. Antibacterial and antifungal activities of the extracts
were tested against standard and isolated strains of the following bacteria; Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Acinobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis as well as the fungi; Candida albicans and C. parapsilosis. All of the extracts possessed noteworthy activity against ATCC strain of S. aureus (4 μg/ml), while the LC extracts showed reasonable antifungal effect. On the other hand, we found that only the chloroform
extract was active against HSV (16–8 μg/ml), while petroleum ether and alkaloid extracts inhibited potently PI-3 (16–4 μg/ml
and 32–4 μg/ml, respectively). However, all of the extracts had insignificant antiradical effect on DPPH. In addition, we
also analyzed the content of the alkaloid fraction of the plant by capillary gas chromatography-mass spectrometry (GC-MS)
and identified lycopodine as the major alkaloid. 相似文献
992.
993.
Targeting bladder tumor cells in vivo and in the urine with a peptide identified by phage display 总被引:3,自引:0,他引:3
Lee SM Lee EJ Hong HY Kwon MK Kwon TH Choi JY Park RW Kwon TG Yoo ES Yoon GS Kim IS Ruoslahti E Lee BH 《Molecular cancer research : MCR》2007,5(1):11-19
Bladder cancer is one of the most common tumors of the genitourinary tract. Here, we use phage display to identify a peptide that targets bladder tumor cells. A phage library containing random peptides was screened for binding to cells from human bladder tumor xenografts. Phage clones were further selected for binding to a bladder tumor cell line in culture. Six clones displaying the consensus sequence CXNXDXR(X)/(R)C showed selective binding to cells from primary human bladder cancer tissue. Of these, the CSNRDARRC sequence was selected for further study as a synthetic peptide. Fluorescein-conjugated CSNRDARRC peptide selectively bound to frozen sections of human bladder tumor tissue, whereas only negligible binding to normal bladder tissue was observed. When the fluorescent peptide was introduced into the bladder lumen, in a carcinogen-induced rat tumor model, it selectively bound to tumor epithelium. Moreover, when the peptide was intravenously injected into the tail vein, it homed to the bladder tumor but was not detectable in normal bladder and control organs. Next, we examined whether the peptide can detect tumor cells in urine. The fluorescent peptide bound to cultured bladder tumor cells but not to other types of tumor cell lines. Moreover, it bound to urinary cells of patients with bladder cancer, while showing little binding to urinary cells of patients with inflammation or healthy individuals. The CSNRDARRC peptide may be useful as a targeting moiety for selective delivery of therapeutics and as a diagnostic probe for the detection of bladder cancer. 相似文献
994.
995.
A series of N4X (X = O, S, Se) compounds have been examined with ab initio and density functional theory (DFT) methods. To our knowledge,
these compounds, except for the C2v ring and the C3v towerlike isomers of N4O, are first reported here. The ring structures are the most energetically favored for N4X (X = O and S) systems. For N4Se, the cagelike structure is the most energetically favored. Several decomposition and isomerization pathways for the N4X species have been investigated. The dissociation of C2v ring N4O and N4S structures via ring breaking and the barrier height are only 1.1 and −0.2 kcal mol−1 at the CCSD(T)/6-311+G*//MP2/6-311+G* level of theory. The dissociation of the cagelike N4X species is at a cost of 12.1–16.2 kcal mol−1. As for the towerlike and triangle bipyramidal isomers, their decomposition or isomerization barrier heights are all lower
than 10.0 kcal mol−1. Although the CS cagelike N4S isomer has a moderate isomerization barrier (18.3–29.1 kcal mol−1), the low dissociation barrier (−1.0 kcal mol−1) indicates that it will disappear when going to the higher CCSD(T) level.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
996.
Three-dimensional quantitative structure-activity relationship (3D-QSAR) analyses using CoMFA and CoMSIA methods were conducted
on a series of fluoropyrrolidine amides as dipeptidyl peptidase IV (DP-IV) inhibitors. The selected ligands were docked into
the binding site of the 3D model of DP-IV using the GOLD software, and the possible interaction models between DP-IV and the
inhibitors were obtained. Based on the binding conformations of these fluoropyrrolidine amides and their alignment inside
the binding pocket of DP-IV, predictive 3D-QSAR models were established by CoMFA and CoMSIA analyses, which had conventional
r
2 and cross-validated coefficient values () up to 0.982 and 0.555 for CoMFA and 0.953 and 0.613 for CoMSIA, respectively. The predictive ability of these models was
validated by six compounds that were in the testing set. Structure-based investigations and the final 3D-QSAR results provide
the guide for designing new potent inhibitors. 相似文献
997.
998.
Karhánek D Kacer P Kuzma M Splíchalová J Cervený L 《Journal of molecular modeling》2007,13(9):1009-1016
Theoretical investigation of Pt(0)-olefin organometallic complexes containing tertiary phosphine ligands was focused on the
strength of platinum-olefin electronic interaction. DFT theoretical study of electronic effects in a substantial number of
ethylene derivatives was evaluated in terms of the Pt-olefin binding energy using MP2 correlation theory. Organometallics
bearing coordinated olefins with general formula (R1R2C = CR3R4)Pt(PH3)2 [R = various substituents] had been selected, including olefins containing both electron-donor substituents as well as electron-withdrawing
groups. The stability of the corresponding complexes increases with a strengthening electron-withdrawal ability of the olefin
substituents.
Figure Representation of (CH2 = CHR)Pt(PPh3)2 and the stability chart 相似文献
999.
With the help of quantum mechanical calculations, we have examined the series of central system X(ML)3
+(X = O, S, Se; M = Au, Ag, Cu). Using a scalar–relativistic density functional approach, we studied the geometry structures, Mulliken populations and charges of the systems. Structure parameters of the experimental systems are reproduced well with Xα method. The metallophilic interaction energy is analyzed and decomposed. For the systems with different central atoms and different metal atoms, the nature of the metallophilic attraction interaction is analyzed. 相似文献
1000.
In this study, we performed a molecular docking and dynamics simulation for a benzoxazinone–human oxytocin receptor system to determine the possible hydrophobic and electrostatic interaction points in the dynamic complex. After the homology modeling, the ligand was docked into the putative active using AutoDock 3.05. After the application of energetic and structural filters, the complexes obtained were further refined with a simulated annealing protocol (AMBER8) to remove steric clashes. Three complexes were selected for subjection to the molecular dynamics simulation (5 ns), and the results on the occurrence of average anchor points showed a stable complex between the benzoxazinone derivative and the receptor. The complex could be used as a good starting point for further analysis with site-directed mutagenesis, or further computational research.
Figure The location of the ligands (complex B – blue; complex E – red; and complex F –
green) in the transmembrane regions (TM1 – red; TM2 – blue; TM3 – yellow; TM4
– purple; TM5 – orange; TM6 – cyan; TM7 – pink) of the hOTR. For clarity, the EC
and IC loops are not shown
Electronic Supplementary Material Supplementary material is available at 相似文献