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91.
Nikolai F. Zobov Sergei V. Shirin Oleg L. Polyansky Robert J. Barber Pierre-François Coheur Peter F. Bernath Michel Carleer 《Journal of Molecular Spectroscopy》2006,237(1):115-122
An emission spectrum recorded in an oxyacetylene torch [P.-F. Coheur, P.F. Bernath, M. Carleer, R. Colin, O.L. Polyansky, N.F. Zobov, S.V. Shirin, R.J. Barber, J. Tennyson, J. Chem. Phys. 122 (2005) 074307] is analyzed for the region covering stretching fundamentals and associated hot bands of water. Many lines could be assigned on the basis of previously determined energy levels. New assignments made with a new variational linelist allow a further 800 energy levels covering 15 vibrational states and rotations up to J = 32 to be assigned. A simultaneous re-analysis of previously reported sunspot absorption spectra leads to the assignment of 581 further lines in the L-band spectrum and 67 in the N-band spectrum. 相似文献
92.
Sagiv Weintraub Tali Yarnitzky Shirin Kahremany Iliana Barrera Olga Viskind Kobi Rosenblum Masha Y. Niv Arie Gruzman 《Molecular diversity》2016,20(4):805-819
Protein kinase RNA-activated (PKR) plays an important role in a broad range of intracellular regulatory mechanisms and in the pathophysiology of many human diseases, including microbial and viral infections, cancer, diabetes and neurodegenerative disorders. Recently, several potent PKR inhibitors have been synthesized. However, the enzyme’s multifunctional character and a multitude of PKR downstream targets have prevented the successful transformation of such inhibitors into effective drugs. Thus, the need for additional PKR inhibitors remains. With the help of computer-aided drug-discovery tools, we designed and synthesized potential PKR inhibitors. Indeed, two compounds were found to inhibit recombinant PKR in pharmacologically relevant concentrations. One compound, 6-amino-3-methyl-2-oxo-N-phenyl-2,3-dihydro-1H-benzo[d]imidazole-1-carboxamide, also showed anti-apoptotic properties. The novel molecules diversify the existing pool of PKR inhibitors and provide a basis for the future development of compounds based on PKR signal transduction mechanism. 相似文献
93.
Shirin Changizi Mahyar Sameti Gabrielle L. Bazemore Hong Chen Chris A. Bashur 《Macromolecular bioscience》2023,23(9):2300073
Endothelialization of engineered vascular grafts for replacement of small-diameter coronary arteries remains a critical challenge. The ability for an acellular vascular graft to promote endothelial cell (EC) recruitment in the body would be very beneficial. This study investigated epsins as a target since they are involved in internalization of vascular endothelial growth factor receptor 2. Specifically, epsin-mimetic UPI peptides are delivered locally from vascular grafts to block epsin activity and promote endothelialization. The peptide delivery from fibrin coatings allowed for controlled loading and provided a significant improvement in EC attachment, migration, and growth in vitro. The peptides have even more important impacts after grafting into rat abdominal aortae. The peptides prevented graft thrombosis and failure that is observed with a fibrin coating alone. They also modulated the in vivo remodeling. The grafts are able to remodel without the formation of a thick fibrous capsule on the adventitia with the 100 µg mL−1 peptide-loaded condition, and this condition enabled the formation of a functional EC monolayer in the graft lumen after only 1 week. Overall, this study demonstrated that the local delivery of UPI peptides is a promising strategy to improve the performance of vascular grafts. 相似文献
94.
Seyed Majid Hashemianzadeh Shirin Faraji Amir Hossein Amin Sepideh Ketabi 《Monatshefte für Chemie / Chemical Monthly》2008,139(2):89-100
Summary. Interactions of the DNA bases adenine (A), guanine (G), cytosine (C), and thymine (T) with various metal ions (M) of groups IA and IIA of the periodic table of the elements were studied at the HF, MP2, and DFT levels of theory. The structures and thermodynamic stabilities of these species were studied at the gas phase. The calculations
uphold that there exist two active sites in G and one in A, C, and T. The calculations also show that the O2 atom in T is a more active site for metal ion bindings than that in C. The stability energies for G … M complexes are larger than those for A … M complexes and the stability energies for T … M complexes are larger than those for C … M complexes. As z/r ratio for the metal ion increases, the interaction energy for the complex increases systematically. Thermodynamic quantities
such as ΔH, ΔG, ΔS, and ln K were determined for each complexation reaction, [Base+M
n+ →(Base … M)
n+]. A, G, and C complexation reactions except for C … Rb+ are exothermic. The situation is quite different for T complexation reactions and all except for T … Be2+ and T … Mg2+ are endothermic. 相似文献
95.
Grechko M Maksyutenko P Zobov NF Shirin SV Polyansky OL Rizzo TR Boyarkin OV 《The journal of physical chemistry. A》2008,112(42):10539-10545
We report here an experimental approach that enables measurement of weak transitions to a wide range of rovibrational levels of water in the energy region 27,000-34,200 cm(-1). We have previously demonstrated the use of laser double-resonance overtone excitation to access highly excited vibrational levels from single rovibrational states. Although this approach simplifies the assignment of the spectra, it strongly reduces the number of observed transitions and hence our ability to test theoretical predictions. Here, we increase significantly the number of observed transitions by allowing rotational relaxation of H2O at intermediate levels of the double-resonance excitation scheme to the levels of the same nuclear spin (ortho or para). Our recently developed semiempirical potential energy surface PES12 enables assignment of the resulting complex spectra and reproduction of the measured transitions with accuracy better than 1 cm(-1). 相似文献
96.
In this paper a review of studies on ternary polymer blends, reported in the period from 1980s to 2007, is presented. This review covers the investigations carried out on the formation of morphologies observed in ternary blends including separated disperse, core–shell and co‐continuous morphologies; and also the parameters affecting the type of morphology and its distribution state. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
97.
Zabardasti Abedien Joshaghani Mohammad Nadri Shirin Goudarziafshar Hamid Salehnassaj Maryam 《Structural chemistry》2012,23(5):1497-1502
Structural Chemistry - Ab initio calculations at the MP2/6-311++G(d,p) computational level were used to analyze the interactions between a molecule of B2H6 with some small molecules which often... 相似文献
98.
A single hydrogen bond between an amide N-H and a thiolate sulfur in model complexes designed to mimic the binding site of zinc thiolate proteins, is shown to reduce the reactivity of the thiolate toward electrophiles by up to 2 orders of magnitude. In addition a single such bond is also sufficient to achieve nearly 100% regiospecificity of reaction between a strong, and hence inherently indiscriminate, alkylating agent like trimethyl oxonium tetrafluoroborate and a single sulfur in a dithiolate construct. The importance of these results in understanding how two systems such as the zinc fingers of the GATA family and the Escherichia coli DNA repair protein Ada which share the same pseudotetrahedral structure and tetrascysteinyl ligation around the zinc can fulfill such widely divergent (structural vs reactive) roles and how specificity of reaction in multithiolate-containing systems can be achieved is discussed. 相似文献
99.
It is shown in model complexes designed to mimic the binding site of zinc-thiolate proteins that a single hydrogen bond between an amide N-H and a Zn-coordinated thiolate reduces its reactivity toward electrophiles by up to 2 orders of magnitude. In addition, we show that a single N-H...S hydrogen bond is sufficient to achieve near 100% regiospecificity of reaction between a strong, and hence inherently indiscriminate, alkylating agent like trimethyloxonium tetraflouroborate and a single sulfur in a dithiolate construct. The importance of these results in understanding how systems such as the zinc fingers of the GATA family and the E. coli DNA repair protein Ada, which share the same pseudotetrahedral structure and tetracysteinyl ligation around the zinc, can fulfill such widely divergent (structural vs reactive) roles and how specificity of reaction in such multi-thiolate containing systems can be achieved is discussed. 相似文献
100.
Shirin Bahrami Amarjeet Bassi Ernest Yanful 《Journal of Sol-Gel Science and Technology》2007,42(2):119-126
The application of silica sol–gel particles containing crude metallothionein (MT) was investigated for cadmium removal from
water. The metallothionein was first extracted from the yeast Scchizosaccharomyces pombe, and entrapped in the sol–gel matrices. Then sol–gel particles with the different sizes (ranging from 45 to 225 μm) were
made. The effect of different flow rates as well as different particle sizes on adsorption of cadmium was investigated. The
particle size has a greater effect on Cd adsorption than flow rate in the system studied. The breakthrough curves in the column
were modeled using an empirical two parameter fixed-bed adsorption model. The model relates the changes of cadmium concentration
in effluent to the standard deviation (σ) and characteristic of time (t
0). 相似文献