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951.
Ivana Barravecchia Elisabetta Barresi Camilla Russo Francesca Scebba Chiara De Cesari Valerio Mignucci Davide De Luca Silvia Salerno Valeria La Pietra Mariateresa Giustiniano Sveva Pelliccia Diego Brancaccio Greta Donati Federico Da Settimo Sabrina Taliani Debora Angeloni Luciana Marinelli 《Molecules (Basel, Switzerland)》2021,26(24)
Molecule interacting with CasL 2 (MICAL2), a cytoskeleton dynamics regulator, are strongly expressed in several human cancer types, especially at the invasive front, in metastasizing cancer cells and in the neo-angiogenic vasculature. Although a plethora of data exist and stress a growing relevance of MICAL2 to human cancer, it is worth noting that only one small-molecule inhibitor, named CCG-1423 (1), is known to date. Herein, with the aim to develop novel MICAL2 inhibitors, starting from CCG-1423 (1), a small library of new compounds was synthetized and biologically evaluated on human dermal microvascular endothelial cells (HMEC-1) and on renal cell adenocarcinoma (786-O) cells. Among the novel compounds, 10 and 7 gave interesting results in terms of reduction in cell proliferation and/or motility, whereas no effects were observed in MICAL2-knocked down cells. Aside from the interesting biological activities, this work provides the first structure–activity relationships (SARs) of CCG-1423 (1), thus providing precious information for the discovery of new MICAL2 inhibitors. 相似文献
952.
Valeria Zeni Georgia V. Baliota Giovanni Benelli Angelo Canale Christos G. Athanassiou 《Molecules (Basel, Switzerland)》2021,26(24)
Nowadays, we are tackling various issues related to the overuse of synthetic insecticides. Growing concerns about biodiversity, animal and human welfare, and food security are pushing agriculture toward a more sustainable approach, and research is moving in this direction, looking for environmentally friendly alternatives to be adopted in Integrated Pest Management (IPM) protocols. In this regard, inert dusts, especially diatomaceous earths (DEs), hold a significant promise to prevent and control a wide range of arthropod pests. DEs are a type of naturally occurring soft siliceous sedimentary rock, consisting of the fossilized exoskeleton of unicellular algae, which are called diatoms. Mainly adopted for the control of stored product pests, DEs have found also their use against some household insects living in a dry environment, such as bed bugs, or insects of agricultural interest. In this article, we reported a comprehensive review of the use of DEs against different arthropod pest taxa, such as Acarina, Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera, Ixodida, Lepidoptera, when applied either alone or in combination with other techniques. The mechanisms of action of DEs, their real-world applications, and challenges related to their adoption in IPM programs are critically reported. 相似文献
953.
Luisa Affatigato Alice Sciortino Giuseppe Sancataldo Alessio Incocciati Roberta Piacentini Alessandra Bonamore Marco Cannas Fabrizio Messina Mariano Licciardi Valeria Militello 《Photochemistry and photobiology》2023,99(5):1218-1224
Ferritin nanoparticles play many important roles in theranostic and bioengineering applications and have been successfully used as nanovectors for the targeted delivery of drugs due to their ability to specifically bind the transferrin receptor (TfR1, or CD71). They can be either genetically or chemically modified for encapsulating therapeutics or probes in their inner cavity. Here, we analyzed a new engineered ferritin nanoparticle, made of the H chain mouse ferritin (HFt) fused with a specific lanthanide binding tag (LBT). The HFt-LBT has one high affinity lanthanide binding site per each of the 24 subunits and a tryptophane residue within the tag that acts as an antenna able to transfer the energy to the lanthanide ions via a LRET process. In this study, among lanthanides, we selected europium for its red emission that allows to reduce overlap with tissue auto-fluorescence. Steady state emission measurements and time-resolved emission spectroscopy have been employed to investigate the interaction between the HFt-LBT and the Eu3+ ions. This allowed us to identify the Eu3+ energy states involved in the process and to pave the way for the future use of HFt-LBT Eu3+ complex in theranostics. 相似文献
954.
Dr. Amberley D. Stephens Johanna Kölbel Dr. Rani Moons Chyi Wei Chung Dr. Michael T. Ruggiero Dr. Najet Mahmoudi Dr. Talia A. Shmool Dr. Thomas M. McCoy Dr. Daniel Nietlispach Prof. Alexander F. Routh Prof. Frank Sobott Prof. J. Axel Zeitler Prof. Gabriele S. Kaminski Schierle 《Angewandte Chemie (International ed. in English)》2023,62(7):e202212063
The solvation shell is essential for the folding and function of proteins, but how it contributes to protein misfolding and aggregation has still to be elucidated. We show that the mobility of solvation shell H2O molecules influences the aggregation rate of the amyloid protein α-synuclein (αSyn), a protein associated with Parkinson's disease. When the mobility of H2O within the solvation shell is reduced by the presence of NaCl, αSyn aggregation rate increases. Conversely, in the presence CsI the mobility of the solvation shell is increased and αSyn aggregation is reduced. Changing the solvent from H2O to D2O leads to increased aggregation rates, indicating a solvent driven effect. We show the increased aggregation rate is not directly due to a change in the structural conformations of αSyn, it is also influenced by a reduction in both the H2O mobility and αSyn mobility. We propose that reduced mobility of αSyn contributes to increased aggregation by promoting intermolecular interactions. 相似文献
955.
Jonas Žurauskas Dr. Soňa Boháčová Dr. Shangze Wu Dr. Valeria Butera Simon Schmid Michał Domański Dr. Tomáš Slanina Dr. Joshua P. Barham 《Angewandte Chemie (International ed. in English)》2023,62(44):e202307550
Electron-deficient acridones and in situ generated acridinium salts are reported as potent, closed-shell photooxidants that undergo surprising mechanisms. When bridging acyclic triarylamine catalysts with a carbonyl group (acridones), this completely diverts their behavior away from open-shell, radical cationic, ‘beyond diffusion’ photocatalysis to closed-shell, neutral, diffusion-controlled photocatalysis. Brønsted acid activation of acridones dramatically increases excited state oxidation power (by +0.8 V). Upon reduction of protonated acridones, they transform to electron-deficient acridinium salts as even more potent photooxidants (*E1/2=+2.56–3.05 V vs SCE). These oxidize even electron-deficient arenes where conventional acridinium salt photooxidants have thusfar been limited to electron-rich arenes. Surprisingly, upon photoexcitation these electron-deficient acridinium salts appear to undergo two electron reductive quenching to form acridinide anions, spectroscopically-detected as their protonated forms. This new behaviour is partly enabled by a catalyst preassembly with the arene, and contrasts to conventional SET reductive quenching of acridinium salts. Critically, this study illustrates how redox active chromophoric molecules initially considered photocatalysts can transform during the reaction to catalytically active species with completely different redox and spectroscopic properties. 相似文献
956.
Dr. Michele Porto Prof. Ruggero Angelico Dr. Pietro Calandra Dr. Valeria Loise Dr. Abraham A. Abe Prof. Cesare Oliviero Rossi Dr. Paolino Caputo 《Chemphyschem》2023,24(24):e202300217
In this investigation the dynamics of two types of bitumens with different penetration grade were tested by using dynamic shear rheometry (DSR) and Nuclear Magnetic Resonance (NMR) at unaged conditions, and upon both short- and long-term artificial aging. The gel-sol transition temperature was found to increase with increasing the time of aging treatment. Arrhenius parameters of the viscosity were found, unexpectedly, to be correlated with those of simple liquids, suggesting that the two kinds of systems, although chemically and physically quite different, share the same basic process at the molecular level. The molecular dynamics has been then investigated by NMR Pulsed Field Gradient Stimulated-Echo (PFGSE) and relaxometry (Carr-Purcell-Meiboom-Gill, CPMG, spin-echo pulse sequence) to capture the effect of aging upon dynamics variables such as self-diffusion coefficients D and transverse relaxation times T2. The translational diffusion at T> of the light molecular components of both types of bitumens was characterized by broad distributions of D which were found independent of the experimental time scale up to 0.2 s. Similarly, T2 data could be described as a continuous unimodal distributions of relaxation times determined both at T< and T> . 相似文献
957.
958.
Maria Carannante Valeria D'Amato Paola Fersini Salvatore Forte Giuseppe Melisi 《商业与工业应用随机模型》2023,39(4):549-566
Dependence among different cyber risk classes is a fundamentally underexplored topic in the literature. However, disregarding the dependence structure in cyber risk management leads to inconsistent estimates of potential unintended losses. To bridge this gap, this article adopts a regulatory perspective to develop vine copulas to capture dependence. In quantifying the solvency capital requirement gradient for cyber risk measurement according to Solvency II, a dangerous paradox emerges: an insurance company does not tend to provide cyber risk hedging products as they are excessively expensive and would require huge premiums that it would not be possible to find policyholders. 相似文献
959.
In this work reliable experimental data for three semicrystalline polymers (iPP, PA6, PET) crystallised under pressure and high cooling rates are supplied. These results were achieved on the basis of a model experiment where drastic “controlled” solidification conditions are applied. The final objective was to quantify the effect of two typical operating conditions (pressure and cooling rate) on the final properties and morphology of the obtained product. The influence of processing conditions on some macroscopically relevant properties, such as density and micro hardness is stressed, together with the influence of processing conditions on the product morphology, investigated by means of Wide Angle X-Ray Scattering (WAXS). Results on the iPP samples display a decrease of density and micro hardness, due to the pressure increase, in a wide range of cooling rates (from 0.01 to 20°C/s). PET samples exhibit an opposite behaviour with density and micro hardness increasing at higher pressures in the whole range of cooling rates investigated. PA6 samples behave similarly to PET displaying a less significant increase of density and micro hardness with pressure than PET samples. 相似文献