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31.
Anna Carbone Stella Cascioferro Barbara Parrino Daniela Carbone Camilla Pecoraro Domenico Schillaci Maria Grazia Cusimano Girolamo Cirrincione Patrizia Diana 《Molecules (Basel, Switzerland)》2021,26(1)
Anti-virulence strategy is currently considered a promising approach to overcome the global threat of the antibiotic resistance. Among different bacterial virulence factors, the biofilm formation is recognized as one of the most relevant. Considering the high and growing percentage of multi-drug resistant infections that are biofilm-mediated, new therapeutic agents capable of counteracting the formation of biofilms are urgently required. In this scenario, a new series of 18 thiazole derivatives was efficiently synthesized and evaluated for its ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 25923 and S. aureus ATCC 6538 and the Gram-negative strain Pseudomonas aeruginosa ATCC 15442. Most of the new compounds showed a marked selectivity against the Gram-positive strains. Remarkably, five compounds exhibited BIC50 values against S. aureus ATCC 25923 ranging from 1.0 to 9.1 µM. The new compounds, affecting the biofilm formation without any interference on microbial growth, can be considered promising lead compounds for the development of a new class of anti-virulence agents. 相似文献
32.
Marco Verona Sara Rubagotti Stefania Croci Sophia Sarpaki Francesca Borgna Marianna Tosato Elisa Vettorato Giovanni Marzaro Francesca Mastrotto Mattia Asti 《Molecules (Basel, Switzerland)》2021,26(4)
The cholecystokinin-2 receptor (CCK-2R) is overexpressed in several human cancers but displays limited expression in normal tissues. For this reason, it is a suitable target for developing specific radiotracers. In this study, a nastorazepide-based ligand functionalized with a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelator (IP-001) was synthesized and labelled with indium-111. The radiolabeling process yielded >95% with a molar activity of 10 MBq/nmol and a radiochemical purity of >98%. Stability studies have shown a remarkable resistance to degradation (>93%) within 120 h of incubation in human blood. The in vitro uptake of [111In]In-IP-001 was assessed for up to 24 h on a high CCK-2R-expressing tumor cell line (A549) showing maximal accumulation after 4 h of incubation. Biodistribution and single photon emission tomography (SPECT)/CT imaging were evaluated on BALB/c nude mice bearing A549 xenograft tumors. Implanted tumors could be clearly visualized after only 4 h post injection (2.36 ± 0.26% ID/cc), although a high amount of radiotracer was also found in the liver, kidneys, and spleen (8.25 ± 2.21%, 6.99 ± 0.97%, and 3.88 ± 0.36% ID/cc, respectively). Clearance was slow by both hepatobiliary and renal excretion. Tumor retention persisted for up to 24 h, with the tumor to organs ratio increasing over-time and ending with a tumor uptake (1.52 ± 0.71% ID/cc) comparable to liver and kidneys. 相似文献
33.
Alexandra Bod Lilla Radvnyi Tams Kszegi Rita Csepregi Dvid U. Nagy gnes Farkas Marianna Kocsis 《Molecules (Basel, Switzerland)》2021,26(9)
Melissopalynology, antioxidant capacity and mineral and toxic element contents were analyzed in eight types of Hungarian honeys. Based on color, two groups were distinguished: light honeys comprised acacia, amorpha, phacelia and linden honeys; while dark honeys included sunflower, chestnut, fennel and sage honeys, with 100 to 300 and 700 to 1500 mAU, respectively. The unifloral origin of each sample was supported using pollen analysis. The absorbance of honey correlated positively with antioxidant capacity determined by three different methods (TRC, DPPH, ORAC), and also with mineral content. The exception was the light amber linden honey with significantly higher K content and antiradical activity than other light honeys. The Mn, Zn and Fe contents were the highest in chestnut, sunflower and fennel honeys, respectively. The black meadow sage honey performed best regarding the content of other elements and antioxidant activity. The concentrations of several toxic elements were below the detection limit in the samples, indicating their good quality. The principal component analysis (PCA) revealed correlations between different antioxidant assays and minerals, and furthermore, confirmed the botanical authentication of the honeys based on the studied parameters. To our best knowledge, the present study is the first to provide a complex analysis of quality parameters of eight unifloral Hungarian honeys. 相似文献
34.
A Highly Luminescent Tetramer from a Weakly Emitting Monomer: Acid‐ and Redox‐Controlled Multiple Complexation by Cucurbit[7]uril
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Dr. Giacomo Bergamini Andrea Fermi Marianna Marchini Mirko Locritani Prof. Alberto Credi Prof. Margherita Venturi Prof. Fabrizia Negri Prof. Paola Ceroni Dr. Massimo Baroncini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):7054-7060
The tetrahedral, shape‐persistent molecule 1 4+, containing four pyridylpyridinium units connected through a central carbon atom, exhibits unexpected photophysical properties including a substantially redshifted absorption (2350 cm?1) and a very strong fluorescence (Φem=40 %), compared with the monomer 2 + (Φem=0.4 %). Density functional theory calculations on the structure and spectroscopic properties of 1 4+ and 2 + show that exciton interactions, homoconjugation, and orbital nature account for the observed differences in their photophysical properties. The protonated tetramer binds four cucurbit[7]uril molecules and the host/guest interactions can be controlled by chemical (acid/base) as well as redox stimuli. 相似文献
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37.
Cucinotta V Giuffrida A Grasso G Maccarrone G Messina M 《Journal of chromatography. A》2002,979(1-2):137-145
Six different racemates of the profen family were used as analytes in order to test the chiral selector properties of three members of a new class of cyclodextrin derivatives, hemispherodextrins (HMs), in capillary electrophoresis. In addition to experiments carried out to separate each enantiomeric pair one by one, other experiments were carried out on samples containing all six enantiomeric pairs. Electropherograms were obtained either by adding a single HM to the background electrolyte (BGE), or a binary mixture of HMs. The results obtained confirm the excellent chiral selector properties of the HMs, and furthermore show that these compounds can also be used for achiral selection. When mixing different HMs, a complementary effect in chiral selectivity is observed, which, in our opinion, deserves further study. 相似文献
38.
Marina Quartu Maria Pina Serra Marianna Boi Viviana Ibba Tiziana Melis Marina Del Fiacco 《BMC neuroscience》2008,9(1):108
Background
The polysialylated neuronal cell adhesion molecule (PSA-NCAM) is considered a marker of developing and migrating neurons and of synaptogenesis in the immature vertebrate nervous system. However, it persists in the mature normal brain in some regions which retain a capability for morphofunctional reorganization throughout life. With the aim of providing information relevant to the potential for dynamic changes of specific neuronal populations in man, this study analyses the immunohistochemical occurrence of PSA-NCAM in the human trigeminal ganglion (TG) and brainstem neuronal populations at prenatal and adult age. 相似文献39.
Luciano Carbone 《Rendiconti del Circolo Matematico di Palermo》1979,28(1):115-133
We give some solution existence and uniqueness theorems for the Volterra type equations systems (1) and (6). 相似文献
40.
Low-frequency current fluctuations are investigated over a bias range covering Ohmic, trap-filling, and space-charge-limited current regimes in polycrystalline polyacenes. The relative current noise power spectral density S(f) is constant in the Ohmic region, steeply increases at the trap-filling transition region, and decreases in the space-charge-limited-current region. The noise peak at the trap-filling transition is accounted for within a continuum percolation model. As the quasi-Fermi level crosses the trap level, intricate insulating paths nucleate within the Ohmic matrix, determining the onset of nonequilibrium conditions at the interface between the insulating and conducting phase. The noise peak is written in terms of the free and trapped charge carrier densities. 相似文献