Search results for " molecule"
showing 10 items of 1523 documents
Endothelial cell colonization and angiogenic potential of combined nano- and micro-fibrous scaffolds for bone tissue engineering
2008
Presently the majority of tissue engineering approaches aimed at regenerating bone relies only on postimplantation vascularization. Strategies that include seeding endothelial cells (ECs) on biomaterials and promoting their adhesion, migration and functionality might be a solution for the formation of vascularized bone. Nano/micro-fiber-combined scaffolds have an innovative structure, inspired by extracellular matrix (ECM) that combines a nano-network, aimed to promote cell adhesion, with a micro-fiber mesh that provides the mechanical support. In this work we addressed the influence of this nano-network on growth pattern, morphology, inflammatory expression profile, expression of structura…
4-(3H)-quinazolinones N-3 substituted with a five membered heterocycle: A promising scaffold towards bioactive molecules
2020
Abstract The quinazolinone nucleus represents, among the class of fused heterocycles, a very important scaffold to obtain molecules with biological activities. A review of literature revealed how such kind of fused heterocycles, coming from natural or synthetic source, are associated with a wide range of biological activities. This review is mainly directed towards the 4-(3H)-quinazolinones N-3 substituted with a five membered heterocycle in which all the possible combinations of nitrogen, sulfur and oxygen atoms are present.
Fast apparent oscillations of fundamental constants
2019
Precision spectroscopy of atoms and molecules allows one to search for and to put stringent limits on the variation of fundamental constants. These experiments are typically interpreted in terms of variations of the fine structure constant $\alpha$ and the electron to proton mass ratio $\mu=m_e/m_p$. Atomic spectroscopy is usually less sensitive to other fundamental constants, unless the hyperfine structure of atomic levels is studied. However, the number of possible dimensionless constants increases when we allow for fast variations of the constants, where "fast" is determined by the time scale of the response of the studied species or experimental apparatus used. In this case, the relevan…
Intrinsic Organic Semiconductors as Hole Transport Layers in p–i–n Perovskite Solar Cells
2021
Thin polymeric and small-molecular-weight organic semiconductors are widely employed as hole transport layers (HTLs) in perovskite solar cells. To ensure ohmic contact with the electrodes, the use of doping or additional high work function (WF) interlayer is common. In some cases, however, intrinsic organic semiconductors can be used without any additive or buffer layers, although their thickness must be tuned to ensure selective and ohmic hole transport. Herein, the characteristics of thin HTLs in vacuum-deposited perovskite solar cells are studied, and it is found that only very thin (<5 nm) HTLs readily result inhigh-performing devices, as the HTL acts as a WF enhancer while still ens…
Cycloadditions of vinylindoles with chiral carbodienophiles: the first asymmetric Diels-Alder reactions in the vinylhetarane series
1993
Abstract The first asymmetric Diels-Alder reactions of some 3- and 2-vinylindoles with (N-propenoyl)bornane-10,2-sultam are described. With one exception, the experimental results are indicative of a high π-facial diastereoselectivity. Following a related procedure, 3-vinylindoles were also allowed to react with a racemic bis(naphthylsulfonyl)-dienophile to furnish tetrahydrocarbazoles with endo-diastereoselectivity.
Weak aurophilic interactions in a series of Au(III) double salts.
2015
In this work, several new examples of rare AuIII⋯AuIII aurophilic contacts are reported. A series of gold(III) double salts and complexes, viz. [AuX2(L)][AuX4] (L = 2,2′-bipyridyl, X = Cl 1, Br 2; L = 2,2′-bipyrimidine, X = Cl 3, Br 4; L = 2,2′-dipyridylamine, X = Cl 5, Br 6), [AuX3(biq)] (biq = 2,2′-biquinoline, X = Cl 7, Br 8), [LH][AuX4] (L = 2,2′-bipyridyl, X = Cl 9; L = 2,2′-bipyrimidine, X = Cl 12; L = 2,2′-dipyridylamine, X = Cl 14, Br 15; L = 2,2′-biquinoline, X = Cl 17, Br 18), [AuBr2(bpy)]2[AuBr4][AuBr2] 10, [AuCl2(bpm)][AuCl2] 11, (bpmH)2[AuBr4][AuBr2] 13, and (dpaH)[AuBr2] 16 (1, 2, and 7 were reported earlier) was synthesized by coordination of a particular ligand to the AuIII …
CARATTERIZZAZIONE MOLECOLARE DI BATTERI IN REPERTI LIGNEI SOMMERSI
2013
The focus of this study was the identification of bacterial colonies in waterlogged wood fragments from the rostrum of a excellent workmanship, that is very likely one of the wrecks attributed to Sextus Pompey fleet (36 BC) and discovered in Acqualadroni, Messina, Sicily, Italy (2008). The wood samples were analyzed by light and Scanning Electron Microscopy (SEM), in vitro culture and molecular technique (DNA base techniques). The results, focused on bacterial consortia, allowed us to reveal the presence of Pseudomonas sp., Sphingomonas sp., Xanthomonas sp. besides Marinobacter sp. and Desulforudis audaxviator. A prompt and accurate characterization of bacterial colonization represents one …
Plant extracts to control microbial growth: a “green” potential strategy
2016
growth process and vegetative development have a direct consequence on the conservation of cultural assets. Recently, due to the use of many chemical compounds applied in biodeteriogens growth control, the attention has been focused on the risks resulting from these treatments that may affect human health (operators, visitors) and the environment. In order to develop alternative methods to traditional biocides, several studies have been focused to various natural products with potential antimicrobial activity, particularly against fungi and bacteria associated with the biodeterioration of cultural assets (Borrego et al., 2012; Sakr et al., 2012; Guiamet et al., 2008). In this study, antimic…
Cnidarian inflammatory reaction and bioactive molecules: from multifunctional role to cultural heritage applications
2015
The renewed interest in the study of genes of immunity in Cnidaria has led to additional information to the scenario of the first stages of immunity evolution revealing the cellular processes involved in symbiosis, in the regulation of homeostasis and in the fight against infections. We investigated the inflammatory response in Anemonia sulcata (Cnidaria: Anthozoa), following injection of various substances different in type and dimension, and observed clear, strong and specific reactions especially after injection of bacteria. The enzymes evaluation (protease, phosphatase and esterase), showing how the injection of different bacterial strains alters the expression of these enzymes suggesti…