Estudios de acoplamiento molecular de nuevos análogos de quinolonas a la ADN girasa de Escherichia coli

Indexación: Scopus.Chemicals and CAS Registry Numbers: amino acid, 65072-01-7; ciprofloxacin, 85721-33-1; DNA topoisomerase (ATP hydrolysing); gatifloxacin, 112811-59-3, 180200-66-2; levofloxacin, 100986-85-4, 138199-71-0; lomefloxacin, 98079-51-7; moxifloxacin, 151096-09-2; nalidixic acid, 389-08-2; oxolinic acid, 14698-29-4; pipemidic acid, 51940-44-4; rufloxacin, 101363-10-4; sitafloxacin, 127254-12-0, 163253-35-8Context: Bacterial resistance to antibiotics is the inevitable consequence of the use of antimicrobial agents. Thus, quinolones are an important class of antibacterials; these agents generally consist of a 1-subtituted-1,4-dihydro-4-oxopyridine-3-carboxylic acid moiety combined with an aromatic or heteroaromatic ring fused at the 5- and 6-position. Aims: To determine the binding of quinolones to DNA gyrase of Escherichia coli. Methods: An analysis was performed using an in silico approach to determine, by docking calculations and energy descriptors, the conformer of 4‐oxo‐1,4‐dihydroquinoline skeleton that forms the most stable complex with DNA gyrase of E. coli. Results: The complex shows that the pose of the quinolones coincides with the amino acid residues Asp87, Thr88, Arg91 and Met92, which is expected to be critical in the binding of quinolones to DNA gyrase of E. coli. A series of quinolones were computationally designed, and the interactions between the quinolones and the amino acid residues of the DNA gyrase were calculated. Conclusions: Among the designed compounds, compounds 105 and 115 exhibit higher binding energy values and interact with amino acids Asp87, Thr88, Arg91 and Met92. © 2018 Journal of Pharmacy & Pharmacognosy Research.http://jppres.com/jppres/pdf/vol6/jppres18.368_6.5.386.pd

Magic in the ancient Greco-Roman and ancient Jewish worlds

In Drawing Down the Moon: Magic in the Ancient Greco-Roman World, Radcliffe Edmonds provides us with a new etic framework for understanding ancient magic, but one steeped in the emic perspectives of the actual practitioners and clients as preserved in the literary, epigraphic, and archaeological evidence. In this paper I examine Edmonds’s findings in relation to the ancient Jewish magical and mystical traditions found mainly in Sefer HaRazim, “The Book of the Mysteries,” a late-antique ritual handbook written in Hebrew.Publisher PDFPeer reviewe

Evaluation of the geotechnical behaviour of a volcanic soil wall with additions of lime and cement against landslides

The construction of earth walls can be a significant response to prevent the next landslides from reaching the road and avoid accidents. Therefore, a material of the same slope was used and reinforced with mixtures of lime and cement, with this same reinforced material a mechanically stabilized hypothetical earth wall (MSE) was developed. An analysis of the original slope was developed to check if there was a possible failure through its safety factor. Then, a hypothetical wall was developed with a floor reinforced with mixtures, in order to assess its overall safety factor and its maximum landslides. According to the results, in principle it was determined that the dosage M-3 / C-4-4 improves in a range of 30% to 37% the friction angle. In addition, it was found that a reinforced wall, that is to say with Lime and cement additions, presents a better behaviour. In its effect, its displacements are about 8 mm and have a global factor of 1.23

Experimental and Numerical Analysis of Skin-Stiffener Separation Using a Seven-Point Bend Configuration

Skin-stiffener separation in stiffened composite panels consists of a complex interaction between multiple scales of progressive damage and failure mechanisms. This work used a superposed cohesive element method of modeling resistance curve effects that represents the structural interface of a unidirectional tape skin and a fabric stiffener. Finite element models using cohesive elements with input properties obtained from tape-to-fabric interface characterization tests were compared to experimental results of a stable skin-stiffener separation characterization test using a seven-point bend fixture. This fixture deformed the stiffened panel specimens into a buckled configuration which induced mixed-mode interlaminar stress states at the skin-stiffener interface. The advantage of this fixture was the potential for more stable damage initiation and delamination growth compared to a stringer-stiffened panel under axial compression. Use of the superposed cohesive elements showed promise, but the characterization of interface material properties as input to the cohesive elements remains a crucial component to be investigated to ensure accurate prediction of skin-stiffener separation