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91.
Stable Peptides Instead of Stapled Peptides: Highly Potent αvβ6‐Selective Integrin Ligands 下载免费PDF全文
Dr. Oleg V. Maltsev Dr. Udaya Kiran Marelli Tobias G. Kapp Dr. Francesco Saverio Di Leva Dr. Salvatore Di Maro Dr. Markus Nieberler Prof. Dr. Ute Reuning Prof. Dr. Markus Schwaiger Prof. Dr. Ettore Novellino Prof. Dr. Luciana Marinelli Prof. Dr. Horst Kessler 《Angewandte Chemie (International ed. in English)》2016,55(4):1535-1539
The αvβ6 integrin binds the RGD‐containing peptide of the foot and mouth disease virus with high selectivity. In this study, the long binding helix of this ligand was downsized to an enzymatically stable cyclic peptide endowed with sub‐nanomolar binding affinity toward the αvβ6 receptor and remarkable selectivity against other integrins. Computational studies were performed to disclose the molecular bases underlying the high binding affinity and receptor subtype selectivity of this peptide. Finally, the utility of the ligand for use in biomedical studies was also demonstrated here. 相似文献
92.
Cristina M. Belfiore Mauro F. La Russa Luciana Randazzo Giuseppe Montana Antonino Pezzino Silvestro A. Ruffolo Piergiorgio Aloise 《Applied Physics A: Materials Science & Processing》2014,114(3):741-752
The present contribution is part of a biennial research project funded by the Italian Ministry of Education, Universities and Research (MIUR). This study, currently in progress, deals with innovative experimental approaches applied to the chemical, mineralogical and physical transformations occurring during the prolonged permanence of archaeological ceramic finds in seawater environments as well as to restoration and conservation issues of the same underwater artifacts. The experimental approach used in this research consisted in the manufacture of ceramic test-pieces (briquettes) and their successive placing in underwater environment. This work aims at assessing how textural and compositional parameters along with firing temperatures of a ceramic paste could affect total porosity, pore size distribution and kinetics of capillary water absorption. A further purpose is concerned with the study of the potential modification of porosity and pore size distribution in the same ceramic bodies after immersion in seawater (3 and 6 months). The study was carried out using a multi-technique approach including investigations through polarized light microscopy (PLM), capillary water absorption test, mercury intrusion porosimetry (MIP) analyses and theoretical calculation of salt crystallization pressures. The obtained results show a different behavior of the six experimental pastes as a function of their compositional and textural features as well as pore size distribution and firing temperatures. These parameters, in various extents, have been found significantly influencing the kinetics of water absorption and the susceptibility of ceramic artifacts to salt crystallization processes, with important implications on conservation procedures needed before the musealization. 相似文献
93.
Ciminiello P Dell'Aversano C Dello Iacovo E Fattorusso E Forino M Grauso L Tartaglione L Guerrini F Pezzolesi L Pistocchi R Vanucci S 《Journal of the American Chemical Society》2012,134(3):1869-1875
Since 2005, the benthic dinoflagellate Ostreopsis cf. ovata has bloomed across the Mediterranean basin, provoking serious toxic outbreaks. LC/MS studies have identified a number of palytoxin-like compounds, termed ovatoxins, along with trace amounts of putative palytoxin as the causative agents of the O. cf. ovata -related human sufferings. So far, any risk assessment for ovatoxins as well as establishment of their allowance levels in seafood has been prevented by the lack of pure toxins. The present paper reports on the isolation, NMR-based structural determination, and preliminary mouse lethality evaluation of ovatoxin-a, the major toxic compound contained in O. cf. ovata extracts. Availability of pure ovatoxin-a will open the double prospect of fully evaluating its toxicity and preparing reference standards to be employed in LC/MS quantitative analyses. Elucidation of ovatoxin-a's complex structure will ultimately herald the understanding of the molecular bases of ovatoxins bioactivity. 相似文献
94.
Santos AK Machado LL Bizerra AM Monte FJ Santiago GM Braz-Filho R Lemos TL 《Natural product communications》2012,7(6):729-730
A new indole alkaloid of the pyridocarbazole type, named 6N-hydroxy-olivacine, and two known compounds, 2N-oxide-olivacine and olivacine, were isolated from roots of Peschiera affinis. The structures of the compounds were determined by spectroscopic {IR and extensive NMR (COSY, HMQC, HMBCand NOESY)} and EIMS analysis. 相似文献
95.
dos Anjos JV Srivastava RM Costa-Silva JH Scotti L Scotti MT Wanderley AG Leite ES de Melo SJ Mendonça Junior FJ 《Molecules (Basel, Switzerland)》2012,17(1):809-819
In this study, the antinociceptive properties of 3,4-dihydro-2,6-diaryl-4-oxo-pyrimidine-5-carbonitrile derivatives 5a-i at doses of 25 and 50 mg/kg were evaluated in mice, using the abdominal constriction test. Molecular modeling studies were also performed using density functional theory calculations. These data provided information about the electrostatic and ionization potentials and were used to compare the antinociceptive activity of the title compounds. The most active compounds were 3,4-dihydro-2-(4-chlorophenyl)-6-(4-methoxyphenyl)-4-oxo-pyrimidine-5-carbonitrile (5b) and 3,4-dihydro-2,6-diphenyl-4-oxo-pyrimidine-5-carbonitrile (5i), which inhibited the number of abdominal constrictions, at 50 mg/kg dose, in 88.6% and 88% of the sample, respectively. A preliminary SAR study demonstrated that halogen replacement in the phenyl rings of the compounds under study reduces the antinociceptive activity. DFT calculations showed that there is a high correlation between the ionization potentials and the analgesic properties of the compounds. It was found that compounds with a positive ionization potential (compounds 5b and 5i) were found to be the best analgesic drugs in this series. 相似文献
96.
Gonçalves Luciana R. B. Suzuki Glória S. Giordano Roberto C. Giordano Raquel L. C. 《Applied biochemistry and biotechnology》2001,91(1-9):691-702
Applied Biochemistry and Biotechnology - Kinetic and mass transport parameters were estimated for maltotriose hydrolysis using glucoamylase immobilized on macroporous silica and wrapped in pectin... 相似文献
97.
Giordano Raquel L. C. Hirano Paulo C. Gonçalves Luciana R. B. Netto Willibaldo Schmidell 《Applied biochemistry and biotechnology》2000,84(1-9):643-654
This article presents a detailed study on the conditions for achieving a stable biocatalyst to be used in the production of
ethanol from starch. Different pellets were used depending on which characteristic of the biocatalyst was being studied: (a)
Saccharomyces cerevisiae entrapped in pectin or calcium alginate gel particles; (b) silica containing immobilized glucoamylase entrapped in pectin
gel particles; or (c) pectin gel particles, with the silicaenzyme derivative and yeast coimmobilized. The influence of several
variables on the mechanical resistance of the particle, on the viability of the microorganism, and on the rate of substrate
hydrolysis was studied with biocatalyst. The best conditions found were 6% pectin gel, 2-mm particle diameter, and curein
0.2 M CaCl2·2H2O/60 mM acetate buffer, pH 4.2, for gel preparation; and 6.0 g/L of CaCl2·2H2O in the fermentation medium. Biocatalyst (c) was successfully tested for the production of ethanol from liquefield manioc
flour syrup. 相似文献
98.
Carlo Anchisi Luciana Corda Anna Maria Fadda Antonio Maccioni Gianni Podda 《Journal of heterocyclic chemistry》1984,21(2):577-581
A new series of macrocyclic compounds containing 1,2-cyclohexanediols and 2,3-butandiol sub-unit have been prepared treating the stannolanic and stibolanic derivatives with diacyl chlorides. The structures of the compounds prepared have been determined by elemental analysis and spectroscopic data. 相似文献
99.
Griselda Barrera Galland Luciana P. Da Silva Marcos L. Dias Geraldo L. Crossetti Cludio M. Ziglio Carlos A. L. Filgueiras 《Journal of polymer science. Part A, Polymer chemistry》2004,42(9):2171-2178
A complete 13C NMR characterization of a polymer synthesized with a new Ni‐diimine complex [DADNi(NCS)2, where DAD = 2,6‐iPr? C6H3? N?C(Me)? C(Me)? N? 2,6‐iPr? C6H3] activated by methylaluminoxane by homopolymerization of propylene is presented. The amorphous material was made up mainly of blocks of syndiotactic polypropylene and ethylene–propylene copolymer. Some degree of propylene inversion (<1.2 mol %) and of long isobutyl and 2‐methyl hexyl branching (<1 mol %) were assigned and quantified. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2171–2178, 2004 相似文献
100.
Carlo Anchisi Luciana Corda Anna Maria Fadda Anna Maria Maccioni Gianni Podda 《Journal of heterocyclic chemistry》1988,25(3):735-737
Three new macrocyclic polyether-diester have been prepared. The catalytic activity of these compounds has been tested in the Br/I exchange reactions of octyl bromide with different ionic diameter cations. 相似文献