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71.
Fernanda Rodríguez-Enríquez Dr. Dolores Viña Dr. Eugenio Uriarte Dr. Reyes Laguna Dr. Maria J. Matos 《ChemMedChem》2021,16(1):179-186
This study explores the potential of 7-amidocoumarins as multitarget agents against Parkinson's and Alzheimer's diseases, by modulating the substitution patterns within the scaffold. Sixteen compounds were synthesized via 7-amino-4-methylcoumarin acylation, and in vitro evaluation of the molecules against hMAO-A, hMAO-B, hAChE, hBuChE and hBACE1 was performed. Five compounds turned out to be potent and selective hMAO-B inhibitors in the nanomolar range, six displayed inhibitory activity of hMAO-A in the low micromolar range, one showed hAChE inhibitory activity and another one hBACE1 inhibitory activity. MAO-B reversibility profile of 7-(4’-chlorobenzamido)-4-methylcoumarin ( 10 ) was investigated, with this compound being a reversible inhibitor. Neurotoxicity on motor cortex neurons and neuroprotection against H2O2 were also studied, corroborating the safety profile of these molecules. Finally, theoretical ADME properties were also calculated, showing these molecules as good candidates for the optimization of a lead compound. Results suggest that by modulating the substitution pattern at position 7 of the scaffold, selective or multitarget molecules can be achieved. 相似文献
72.
Eugenio Meloni Marco Martino Antonio Ricca Vincenzo Palma 《International Journal of Hydrogen Energy》2021,46(26):13729-13747
Hydrogen is a potential green energy vector. Since the heating of the reforming processes commonly used for its production is obtained by burning hydrocarbons, it has a substantial CO2 footprint. One of the most critical aspects in the methane steam reforming (MSR) reaction is the heat transfer to the catalytic volume, due to the high heat fluxes required to obtain high methane conversions. Consequently, the reactor has complex geometries, along with the heating medium being characterized by temperatures higher than 1000 °C; expensive construction materials and high reaction volumes are therefore needed, resulting in slow thermal transients. These aspects increase the costs (both operative and fixed) as well as cause a decrease in the whole process efficiency. The heat transfer limitations due to the endothermicity of methane steam reforming reaction could be effectively overcome by microwave (MW) heating. This heating technique, that depends only on the dielectric properties of the materials, can result in an efficient and faster method for transferring heat directly to the catalyst, thus generating the heat directly inside the catalytic volume. In this work, Ni-based catalysts, differing from each other by the Ni loading (7 and 15 wt% with respect to the washcoat) were prepared. The catalysts were characterized by means of several techniques and tested in the MW-assisted methane steam reforming reaction. Furthermore, the energy balance of the entire process was performed to calculate the energy efficiency, making a preliminary evaluation of its feasibility in distributed hydrogen production also possible. The results of the preliminary tests showed that the prepared structured catalysts are very susceptible to the MW radiation, and that in the presence of the MSR reaction, it is possible to make the system reach a temperature of 900 °C. In the same tests, the CH4 conversion showed a good approach to the thermodynamic equilibrium values starting at temperatures of about 800 °C at a value of gas hourly space velocity (GHSV) of about 5000 h?1. The energy efficiency of the lab-scale system, calculated as the ratio among the energy absorbed by the system and the energy supplied by the microwaves, was about 50%. Future studies will deal with the microwave reactor optimization, aiming at the increase of the energy efficiency of the system, as well as to obtain a higher CH4 conversion at lower temperatures and increase the H2 yield and selectivity. 相似文献
73.
Miriam Saponaro Isabella Giacomini Giulia Morandin Veronica Cocetta Eugenio Ragazzi Genny Orso Ilaria Carnevali Massimiliano Berretta Mariangela Mancini Francesco Pagano Monica Montopoli 《International journal of molecular sciences》2020,21(23)
Benign prostatic hyperplasia (BPH) is an age-related chronic disorder, characterized by the hyperproliferation of prostatic epithelial and stromal cells, which drives prostate enlargement. Since BPH aetiology and progression have been associated with the persistence of an inflammatory stimulus, induced both by Nuclear Factor-kappa B (NF-κB) activation and reactive oxygen species (ROS) production, the inhibition of these pathways could result in a good tool for its clinical treatment. This study aimed to evaluate the antioxidant and anti-inflammatory activity of a combined formulation of Serenoa repens and Urtica dioica (SR/UD) in an in vitro human model of BPH. The results confirmed both the antioxidant and the anti-inflammatory effects of SR/UD. In fact, SR/UD simultaneously reduced ROS production, NF-κB translocation inside the nucleus, and, consequently, interleukin 6 (IL-6) and interleukin 8 (IL-8) production. Furthermore, the effect of SR/UD was also tested in a human androgen-independent prostate cell model, PC3. SR/UD did not show any significant antioxidant and anti-inflammatory effect, but was able to reduce NF-κB translocation. Taken together, these results suggested a promising role of SR/UD in BPH and BPH-linked disorder prevention. 相似文献
74.
F. A. Pulgarín-Agudelo O. Vigil-Galán Jacob A. Andrade-Arvizu J. R. González-Castillo Eugenio Rodríguez-González Maykel Courel Y. Sánchez E. Saucedo 《Journal of Materials Science: Materials in Electronics》2018,29(18):15363-15368
The doping of Cu2ZnSnSe4 semiconductor with Ge element has demonstrated improvements to kesterite solar cell efficiency. However, the impact of different Cu concentrations on Cu2ZnSnGeSe4/CdS solar cell performance has been poorly studied. In this work, Cu2ZnSnGeSe4 thin films with different Cu contents were synthesized by selenization of sequential thermal evaporation precursors. Solar cells based on kesterite-type Cu2ZnSnGeSe4 (CZTGSe) were fabricated and the influence of the Cu thickness on the chemical composition and morphology of the layers and electro-optical properties of solar cells was studied. The stacking process was performed at room substrate temperature. Efficiency values in the range of 2.0–6.8% are reported as a function of Cu concentration. The highest efficiency of 6.8%, was achieved for solar cell with glass/Mo/CZTGSe/CdS/i-ZnO/ITO structure using the stacking of Cu (3 nm)/Sn (248 nm)/Cu (112 nm)/Zn (174 nm)/Ge (20 nm). 相似文献
75.
76.
Vaz Isabela C. F. Macchi Carlos Eugenio Somoza Alberto Rocha Leandro S. R. Longo Elson Cabral Luis da Silva Edison Z. Simões Alexandre Zirpoli Zonta Giulia Malagù Cesare Desimone P. Mariela Ponce Miguel Adolfo Moura Francisco 《Journal of Materials Science: Materials in Electronics》2022,33(15):11632-11649
Journal of Materials Science: Materials in Electronics - This study reports the electrical properties of Nd-doped cerium oxide (CeO2) films synthesized by microwave assisted hydrothermal using a... 相似文献
77.
Jillian Aurisano Abhinav Kumar Abeer Alsaiari Barbara Di Eugenio Andrew Johnson 《Computer Graphics Forum》2020,39(3):229-240
This paper describes results from an observational, exploratory study of visual data exploration in a large, multi-view, flexible canvas environment. Participants were provided with a set of data exploration sub-tasks associated with a local crime dataset and were instructed to pose questions to a remote mediator who would respond by generating and organizing visualizations on the large display. We observed that participants frequently posed requests to cast a net around one or several subsets of the data or a set of data attributes. They accomplished this directly and by utilizing existing views in unique ways, including by requesting to copy and pivot a group of views collectively and posing a set of parallel requests on target views expressed in one command. These observed actions depart from multi-view flexible canvas environments that typically provide interfaces in support of generating one view at a time or actions that operate on one view at a time. We describe how participants used these ‘cast-a-net’ requests for tasks that spanned more than one view and describe design considerations for multi-view environments that would support the observed multi-view generation actions. 相似文献
78.
Uzma Choudry Dr. Derren J. Heyes Dr. Samantha J. O. Hardman Michiyo Sakuma Dr. Igor V. Sazanovich Joyce Woodhouse Dr. Eugenio De La Mora Dr. Martin N. Pedersen Dr. Michael Wulff Dr. Martin Weik Dr. Giorgio Schirò Prof. Nigel S. Scrutton 《Chembiochem : a European journal of chemical biology》2018,19(10):1036-1043
Phytochromes are bilin‐containing photoreceptors that are typically sensitive to the red/far‐red region of the visible spectrum. Recently, phytochromes from certain eukaryotic algae have become attractive targets for optogenetic applications because of their unique ability to respond to multiple wavelengths of light. Herein, a combination of time‐resolved spectroscopy and structural approaches across picosecond to second timescales have been used to map photochemical mechanisms and structural changes in this atypical group of phytochromes. The photochemistry of an orange/far‐red light‐sensitive algal phytochrome from Dolihomastix tenuilepis has been investigated by using a combination of visible, IR and X‐ray scattering probes. The entire photocycle, correlated with accompanying structural changes in the cofactor/protein, are reported. This study identifies a complex photocycle for this atypical phytochrome. It also highlights a need to combine outcomes from a range of biophysical approaches to unravel complex photochemical and macromolecular processes in multi‐domain photoreceptor proteins that are the basis of biological light‐mediated signalling. 相似文献
79.
Figueroa B E 《The Science of the total environment》2008,389(1):1-9
In the past, Cd regulations have imposed trade restrictions on foodstuffs from some developing countries seeking to access markets in the developed world and in recent years, there has been a trend towards imposing more rigorous standards. This trend seems to respond more to public and private sectors strategies in some developed countries to create disguised barriers to trade and to improve market competitiveness for their industries, than to scientifically justified health precautions (sanitary and phytosanitary measures) and/or technical barriers to trade acceptable under the Uruguay Round Agreement of the WTO. Applying more rigorous Cd standards in some developed countries will not only increase production costs in developing countries but it will also have a large impact on their economies highly dependent on international agricultural markets. In the current literature there are large uncertainties in the cause-effect relationship between current levels of Cd intakes and eventual health effects in human beings; even the risk of Cd to kidney function is under considerable debate. Recent works on the importance of zinc:Cd ratio rather than Cd levels alone to determine Cd risk factors, on the one hand, and on the declining trends of Cd level in foods and soils, on the other, also indicate a lack of scientific evidence justifying more restrictive cadmium standards. This shows that developing countries should fight for changing and making more transparent the current international structures and procedures for setting sanitary and phytosanitary measures and technical barriers to trade. 相似文献
80.
In the present paper, the Rasch measurement model is used in the validation and analysis of data coming from the satisfaction section of the first national survey concerning the social services sector carried out in Italy. A comparison between two Rasch models for polytomous data, that is the Rating Scale Model and the Partial Credit Model, is discussed. Given that the two models provide similar estimates of the item difficulties and workers satisfaction, for almost all the items the response probabilities computed using the RSM and the PCM are very close and the analysis of the bootstrap confidence intervals shows that the estimates obtained applying the RSM are more stable than the ones obtained using the PCM, it can be conclude that, for the present data, the RSM is more appropriate than the PCM. 相似文献