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991.
992.
Krygowski TM Szatyłowicz H Zachara JE 《Journal of chemical information and computer sciences》2004,44(6):2077-2082
Aromaticity of the ring of variously substituted phenols in their H-bonded complexes with various bases was a subject of analysis based on 664 geometries retrieved from CSD and by use of the aromaticity index HOMA. GEO and EN, the components of the HOMA index, describing a decrease of aromaticity due to an increase of bond alternation (GEO term) and bond elongation (EN term), were also studied. There is an approximate monotonic dependence of HOMA and GEO on the H-bond strength estimated by the C-O bond length of the hydroxyl group in phenols. 相似文献
993.
Joseph R. Lakowicz Józef Kuśba Yibing Shen Joanna Malicka Sabato D'Auria Zygmunt Gryczynski Ignacy Gryczynski 《Journal of fluorescence》2003,13(1):69-77
We examined the effects of metallic silver island films on resonance energy transfer (RET) between a donor and acceptor bound to double helical DNA. The donor was 4',6-diamidino-2-phenylindole (DAPI) and the acceptor was propidium iodide (PI). Proximity of the labeled DNA to the silver particles resulted in a dramatic increase in RET as seen from the emission spectra and the donor decay times. Proximity to silver particles results in an increase of the Förster distance from 35 Å an to an apparent value of 166 Å. These results suggest a new type of DNA hybridization assays based on RET over distances much longer than the free-space Forster distance. 相似文献
994.
Chris Pickering Maria Hägglund Joanna Szmydynger-Chodobska Fernanda Marques Joana A Palha Linn Waller Adam Chodobski Robert Fredriksson Malin C Lagerström Helgi B Schiöth 《BMC neuroscience》2008,9(1):97
Background
GPR125 belongs to the family of Adhesion G protein-coupled receptors (GPCRs). A single copy of GPR125 was found in many vertebrate genomes. We also identified a Drosophila sequence, DmCG15744, which shares a common ancestor with the entire Group III of Adhesion GPCRs, and also contains Ig, LRR and HBD domains which were observed in mammalian GPR125. 相似文献995.
Tadeusz M. Krygowski Joanna E. Zachara‐Horeglad 《Journal of Physical Organic Chemistry》2007,20(8):594-599
B3LYP/6–311+G** optimization was carried out for azulene and its analogs, in which CH? CH? CH fragment was replaced with O···X···O (X = H or Li). π‐electron delocalization in four possible derivatives with H‐bonding and three possible derivatives with Li‐bonding was described by the use of HOMA index. All derivatives with Li‐bonding exhibit high π‐electron delocalization similar to that found for azulene. Among four H‐bonded systems, two exhibit lower π‐electron delocalization (HOMA < 0.39) and higher total electron energy than the other two derivatives. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
996.
Advances in Surface-Enhanced Fluorescence 总被引:4,自引:0,他引:4
Lakowicz JR Geddes CD Gryczynski I Malicka J Gryczynski Z Aslan K Lukomska J Matveeva E Zhang J Badugu R Huang J 《Journal of fluorescence》2004,14(4):425-441
We report recent achievements in metal-enhanced fluorescence from our laboratory. Several fluorophore systems have been studied on metal particle-coated surfaces and in colloid suspensions. In particular, we describe a distance dependent enhancement on silver island films (SIFs), release of self-quenching of fluorescence near silver particles, and the applications of fluorescence enhancement near metalized surfaces to bioassays. We discuss a number of methods for various shaped silver particle deposition on surfaces. 相似文献
997.
The paper presents and compares the design of three potentiometric transducers: ion-selective field effect transistor (ISFET), solid-state Ag/AgCl electrode and miniaturized classical Ag/AgCl electrode. The reported transducers were fabricated using different, less or more complicated and expensive, technologies. The transducers were constructed to be compatible with the sensor housing of the flow-cell, designed previously. Moreover, the back-side contact structures of the two planar devices, where electrical connectors and the sensing layer are on the opposite sides, facilitated their application in the flow analysis. Exemplary potassium-selective microsensors based on developed transducers were prepared, applying plasticized PVC and polysiloxane membranes containing valinomycine. The determined microsensor performances allowed comparison of their usefulness for multiparameter flow analysis. 相似文献
998.
Geddes CD Gryczynski I Malicka J Gryczynski Z Lakowicz JR 《Combinatorial chemistry & high throughput screening》2003,6(2):109-117
Metallic surfaces and particles can have dramatic effects on fluorescence, including localized excitation, increased quantum yields, increased photostability and increased distances for resonance energy transfer (RET), and directional emission. While all these effects have not yet been realized in a single system, metal-enhanced fluorescence promises to provide the next generation of high sensitivity fluorescence assays for low copy number detection of biochemical species. 相似文献
999.
Dr. Maria Gil-Moles Sebastian Türck Dr. Uttara Basu Dr. Andrea Pettenuzzo Dr. Saurav Bhattacharya Ananthu Rajan Xiang Ma Rolf Büssing Jessica Wölker Dr. Hilke Burmeister Henrik Hoffmeister Pia Schneeberg Andre Prause Petra Lippmann Josephine Kusi-Nimarko Dr. Storm Hassell-Hart Dr. Andrew McGown Dr. Daniel Guest Dr. Yan Lin Dr. Anna Notaro Dr. Robin Vinck Dr. Johannes Karges Dr. Kevin Cariou Dr. Kun Peng Dr. Xue Qin Dr. Xing Wang Dr. Joanna Skiba Dr. Łukasz Szczupak Prof. Dr. Konrad Kowalski Prof. Dr. Ulrich Schatzschneider Dr. Catherine Hemmert Prof. Dr. Heinz Gornitzka Prof. Dr. Elena R. Milaeva Dr. Alexey A. Nazarov Prof. Dr. Gilles Gasser Prof. Dr. John Spencer Dr. Luca Ronconi Prof. Dr. Ulrich Kortz Prof. Dr. Jindrich Cinatl Prof. Dr. Denisa Bojkova Prof. Dr. Ingo Ott 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(71):17928-17940
The global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has called for an urgent need for dedicated antiviral therapeutics. Metal complexes are commonly underrepresented in compound libraries that are used for screening in drug discovery campaigns, however, there is growing evidence for their role in medicinal chemistry. Based on previous results, we have selected more than 100 structurally diverse metal complexes for profiling as inhibitors of two relevant SARS-CoV-2 replication mechanisms, namely the interaction of the spike (S) protein with the ACE2 receptor and the papain-like protease PLpro. In addition to many well-established types of mononuclear experimental metallodrugs, the pool of compounds tested was extended to approved metal-based therapeutics such as silver sulfadiazine and thiomersal, as well as polyoxometalates (POMs). Among the mononuclear metal complexes, only a small number of active inhibitors of the S/ACE2 interaction was identified, with titanocene dichloride as the only strong inhibitor. However, among the gold and silver containing complexes many turned out to be very potent inhibitors of PLpro activity. Highly promising activity against both targets was noted for many POMs. Selected complexes were evaluated in antiviral SARS-CoV-2 assays confirming activity for gold complexes with N-heterocyclic carbene (NHC) or dithiocarbamato ligands, a silver NHC complex, titanocene dichloride as well as a POM compound. These studies might provide starting points for the design of metal-based SARS-CoV-2 antiviral agents. 相似文献
1000.
Vasso Apostolopoulos Joanna Bojarska Tsun-Thai Chai Sherif Elnagdy Krzysztof Kaczmarek John Matsoukas Roger New Keykavous Parang Octavio Paredes Lopez Hamideh Parhiz Conrad O. Perera Monica Pickholz Milan Remko Michele Saviano Mariusz Skwarczynski Yefeng Tang Wojciech M. Wolf Taku Yoshiya Janusz Zabrocki Piotr Zielenkiewicz Maha AlKhazindar Vanessa Barriga Konstantinos Kelaidonis Elham Mousavinezhad Sarasia Istvan Toth 《Molecules (Basel, Switzerland)》2021,26(2)
Peptides are fragments of proteins that carry out biological functions. They act as signaling entities via all domains of life and interfere with protein-protein interactions, which are indispensable in bio-processes. Short peptides include fundamental molecular information for a prelude to the symphony of life. They have aroused considerable interest due to their unique features and great promise in innovative bio-therapies. This work focusing on the current state-of-the-art short peptide-based therapeutical developments is the first global review written by researchers from all continents, as a celebration of 100 years of peptide therapeutics since the commencement of insulin therapy in the 1920s. Peptide “drugs” initially played only the role of hormone analogs to balance disorders. Nowadays, they achieve numerous biomedical tasks, can cross membranes, or reach intracellular targets. The role of peptides in bio-processes can hardly be mimicked by other chemical substances. The article is divided into independent sections, which are related to either the progress in short peptide-based theranostics or the problems posing challenge to bio-medicine. In particular, the SWOT analysis of short peptides, their relevance in therapies of diverse diseases, improvements in (bio)synthesis platforms, advanced nano-supramolecular technologies, aptamers, altered peptide ligands and in silico methodologies to overcome peptide limitations, modern smart bio-functional materials, vaccines, and drug/gene-targeted delivery systems are discussed. 相似文献