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451.
Scavenging of hydroxyl radical by resveratrol and related natural stilbenes after hydrogen peroxide attack on DNA 总被引:1,自引:0,他引:1
Miriam Rossi Francesco Caruso Roberto Antonioletti Angela Viglianti Gianandrea Traversi Stefano Leone Emiliano Basso Renata Cozzi 《Chemico-biological interactions》2013
Resveratrol (3,5,4′-trihydroxystilbene) is of interest due to its role in prevention and therapy of degenerative diseases as cancer and aging. However, depending on its concentration and cell type studied, resveratrol activity appears conflicting. It exerts antioxidant action, as a scavenger of free radicals and as promoter of antioxidant enzyme activity, but resveratrol acts also as a pro-oxidant. Here we present experimental and theoretical studies for resveratrol and two methoxy-derivatives found in plants, pterostilbene and 3,5,4′-trimethoxystilbene. We show that both methoxy-derivatives induce less DNA damage than resveratrol. The protective effects of the three molecules against oxidative DNA damage induced by hydrogen peroxide treatment were analyzed on mammalian cells in vitro. Our data show for the first time that methoxylated derivatives of resveratrol are very efficient in reducing DNA damage: using the same concentration of the three molecules we obtain a relative reduction of 85.5% (pterostilbene), 43.7% (trimethoxystilbene) and 21.1% (resveratrol). Analysis of the crystal structures of pterostilbene and 3,5,4′-trimethoxystilbene, compared to resveratrol, show fewer intermolecular interactions and a lack of planarity, due to packing forces, which is confirmed by density functional theory (DFT) calculations. We also describe the results of DFT calculations (including water solvent effects) in which the three stilbene species scavenge the hydroxyl radical (associated with the H2O2 insult). 相似文献
452.
Jacopo Cerri Emiliano Mori Leonardo Ancillotto Danilo Russo Sandro Bertolino 《Mammal Review》2022,52(1):16-25
- SARS-CoV-2, the virus that caused the COVID-19 pandemic, is genomically similar to a SARS-like beta-coronavirus found in Asian rhinolophid bats. This evolutionary relationship impressed the global media, which then emphasised bats as key actors in the spillover that resulted in the pandemic. In this study, we highlight changes in the traditional and new media coverage of bats and in Internet search volumes that occurred since the beginning of the COVID-19 pandemic in 2020.
- We analysed Google and Wikipedia searches for bats and coronaviruses in 21 countries and eight languages, as well as television broadcasts in the USA, some of which have global coverage, between January 2016 and December 2020. In January 2020, the amount of television news about bats boomed, and news associated with the term ‘bat’ shifted to COVID-19-related topics. A nearly identical pattern was observed in Google searches during 2020 at the global scale. The daily time series of television coverage and Internet search volumes on bats and coronavirus in the USA covaried in the first quarter of 2020, in line with the existence of a media bubble. Time-series analysis revealed that both the Google Trends index and visits to Wikipedia pages about bats boomed in early 2020, despite the fact that this time of year is usually characterised by low search volumes.
- Media coverage emphasised, correctly or not, the role of bats in the COVID-19 pandemic and amplified public interest in bats worldwide. The public image of these mammals, in many cases threatened and important ecosystem service providers, was seriously compromised. We therefore recommend that policymakers and journalists prioritise scientifically accurate communication campaigns about bats, which would help counteract the surge in bat persecution, and leverage interest towards positive human–bat interactions.
453.
Emiliano Cristiani Paolo Frasca Benedetto Piccoli 《Journal of mathematical biology》2011,62(4):569-588
This paper proposes an agent-based model which reproduces different structures of animal groups. The shape and structure of
the group is the effect of simple interaction rules among individuals: each animal deploys itself depending on the position
of a limited number of close group mates. The proposed model is shown to produce clustered formations, as well as lines and
V-like formations. The key factors which trigger the onset of different patterns are argued to be the relative strength of
attraction and repulsion forces and, most important, the anisotropy in their application. 相似文献
454.
455.
Héctor Romero Emiliano Pereira Hugo Naya Héctor Musto 《Journal of molecular evolution》2009,69(2):203-206
One of the historic debates in molecular evolution concerns the strong variation in the genomic guanine–cytosine (GC) content of prokaryotes, which ranges from approximately 20–75%: Is this factor selectively neutral, or is it the result of natural selection? In a previous article published by our group, we showed that inside well-defined taxonomic groups of prokaryotes, strictly aerobic organisms tend to display higher genomic GC levels than strictly anaerobic species. In the present study, we examined the GC content of fragments of DNA obtained from microbial communities along a well-defined environmental gradient: a 4,000-m vertical profile in the North Pacific subtropical gyre. The patterns of GC distribution might be associated with oxygen concentrations in the seawater column. These results give further support to the link between a physiologic trait (aerobic respiration) and genomic GC content. 相似文献
456.