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Cells undergoing xenobiotic or oxidative stress activate the transcription factor nuclear factor erythroid-derived 2-like 2 (Nrf2), which initiates an intrinsic "stress surveillance" pathway. We recently found that the cytokine IL-17D effects a form of extrinsic stress surveillance by inducing antitumor immunity, but how IL-17D is regulated remains unknown. Here, we show that Nrf2 induced IL-17D in cancer cell lines. Moreover, both Nrf2 and IL-17D were induced in primary tumors as well as during viral infection in vivo. Expression of IL-17D in tumors and virally infected cells is essential for optimal protection of the host as il17d(-/-) mice experienced a higher incidence of tumors and exacerbated viral infections compared to wild-type (WT) animals. Moreover, activating Nrf2 to induce IL-17D in established tumors led to natural killer cell-dependent tumor regression. These data demonstrate that Nrf2 can initiate both intrinsic and extrinsic stress surveillance pathways and highlight the use of Nrf2 agonists as immune therapies for cancer and infection.

The accumulation of ions at electrochemical interfaces governs the local chemical environment, which in turn determines the reaction pathways and rates of electrocatalytic processes, including electrochemical CO2 reduction. Imidazolium cations have been shown to promote CO2 reduction in nonaqueous electrolytes, where multiple mechanisms have been proposed for how imidazolium facilitates CO2 reduction. However, many puzzles persist surrounding how imidazolium cations modify local chemical environments at electrochemical interfaces during CO2 reduction. Dialkylimidazolium cations are multifunctional species that interact with adsorbed CO2˙− while also donating protons and forming carbene-mediated coordination complexes. In this work, we exploit the combination of independent proton donor [Et3NH]Cl and aprotic imidazolium cations, namely 1-ethyl-2,3-dimethylimidazolium ([EMMIm]+) and 1-ethyl-2,3,4,5-tetramethylimidazolium ([EM4Im]+) to further illuminate how imidazolium cations promote selective CO2 electrochemical reduction. Our data indicates that the presence of an aromatic, planar delocalized charge region on imidazolium rings plays an essential role in stabilizing CO2˙− to promote electrocatalytic reduction. Kinetic and steady-state electrochemical analysis demonstrates that ring substituents of [EMMIm]+ additionally tune local chemical environments to impact the rate and product distribution of CO2 reduction by limiting the transport of proton donors. Further, we leverage surface-enhanced Raman scattering in the presence of a molecular probe of local electric fields to illustrate that the unique interface-tuning properties of [EMMIm]+ stem from potential-driven assembly at cathodes. Our study highlights how imidazolium substituents can be tuned to regulate interfacial electrochemical environments and illustrates the importance of balancing CO2˙− stabilization and proton transport in sustaining steady-state electrochemical CO2 reduction with high rate and selectivity. More broadly, our results suggest that aromatic cations promote electrochemical CO2 reduction via a distinct "π+–anion" interaction that appears to be the electrostatic analog of the more commonly investigated "cation–π" interaction, which drives self-assembly in proteins and many other biological systems. [ABSTRACT FROM AUTHOR]

Climate warming is believed to have irreversible effects on biodiversity and ecosystem functions. Secondary forests are non-negligible ecosystems in northern China that have attracted much attention because of their instability and sensitivity to global change. However, there is no consensus on the impact of warming on secondary forest succession. In this study, we explored the response of tree species diversity to climate warming in northern secondary forests in China using a series of field surveys combined with annual meteorological data from 2015 to 2021. Our results indicate that the temperature in the study area increased in spring and autumn, while the precipitation increased in spring, summer, and autumn from 2015 to 2021. Changes in species composition in the study area and climate warming were significant in the northern region of China. The importance values of many broadleaf tree species increased, whereas those of local coniferous and broadleaf tree species decreased. The Shannon–Wiener, Simpson, and Margalef indices for the pure forest were significantly lower than those for the broadleaf mixed forest and the conifer–broadleaf mixed forest (p < 0.05) in 2015 and 2021. The highest value for the Pielou index was in the conifer–broadleaf mixed forest (p < 0.05), whereas it was not significantly different between the pure forest and broadleaf mixed forest in 2021. Surprisingly, the secondary broadleaf mixed forest in northern China showed an unfavorable degradation trend under the influence of climate change, just the same as the secondary pure forest. Our work provides an experimental data source for research on secondary forests under various climate change scenarios and is an important reference for predicting and dealing with the impact of global climate change on the adaptive management and protection of secondary ecosystems. [ABSTRACT FROM AUTHOR]