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High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice (Oryza sativa L.). Brassinosteroids play important roles in enhancing crop stress resistance. In this study, we subjected rice cultivars Huanghuazhan (heat-resistant) and IR36 (heat-sensitive) to high temperature (HT, 40 ºC) or normal temperature (NT, 33 ºC) for 7 d at the panicle initiation stage, in conjunction with application of 24-epibrassinolide [EBR, a synthetic brassinolide (BR)] or brassinazole (BRZ, a BR biosynthesis inhibitor) at the beginning of the treatments. HT exacerbated spikelet degeneration and inhibited young panicle growth, which were partially prevented by EBR application, while BRZ application aggravated the reduction in spikelet number. HT decreased the contents of BR, active cytokinins (aCTK), active gibberellins (aGA) and indole-3-acetic acid (IAA), but increased the content of abscisic acid (ABA) in young panicles. The activities of key enzymes involved in sucrose hydrolysis, glycolysis and the tricarboxylic acid cycle in young panicles were decreased with the change of endogenous hormone levels under HT. In addition, the contents of H 2 O 2 and malondialdehyde (MDA) were increased and the activities of antioxidant enzymes were decreased in young panicles. Exogenous application of EBR induced the expression of phytohormone biosynthesis-related genes and down-regulated the expression of phytohormone catabolism-related genes to increase the contents of endogenous BR, aCTK, aGA and ABA, thus promoting the decomposition and utilization of sucrose in young panicles, enhancing the activities of superoxide dismutase, catalase and peroxidase, and reducing the accumulation of H 2 O 2 and MDA in young panicles, whereas application of BRZ had the opposite physiological effects. These results showed that brassinosteroids mediate endogenous phytohormone metabolism to alleviate HT injury at the panicle initiation stage in rice. [ABSTRACT FROM AUTHOR]

The continuously increasing level of atmospheric CO 2 in the atmosphere has led to global warming. Converting CO 2 into other carbon compounds could mitigate its atmospheric levels and produce valuable products, as CO 2 also serves as a plentiful and inexpensive carbon feedstock. However, the inert nature of CO 2 poses a major challenge for its reduction. To meet the challenge, nature has evolved metalloenzymes using transition metal ions like Fe, Ni, Mo, and W, as well as electron-transfer partners for their functions. Mimicking these enzymes, artificial metalloenzymes (ArMs) have been designed using alternative protein scaffolds and various metallocofactors like Ni, Co, Re, Rh, and Fe S clusters. Both the catalytic efficiency and the scope of CO 2 -reduction product of these ArMs have been improved over the past decade. This review first focuses on the natural metalloenzymes that directly reduce CO 2 by discussing their structures and active sites, as well as the proposed reaction mechanisms. It then introduces the common strategies for electrochemical, photochemical, or photoelectrochemical utilization of these native enzymes for CO 2 reduction and highlights the most recent advancements from the past five years. We also summarize principles of protein design for bio-inspired ArMs, comparing them with native enzymatic systems and outlining challenges and opportunities in enzymatic CO 2 reduction. Both natural and artificial metalloenzymes that reduce CO 2 using common electrochemical, photochemical, or photoelectrochemical strategies are reviewed. Structure, active sites, and reaction mechanisms for CO 2 -reducing natural metalloenzymes, as well as examples and designing strategies for designing CO 2 -reducing artificial metalloenzymes are also summarized. [Display omitted] • Describe the structures and reaction mechanisms of natural CO 2 -reducing enzymes. • Introduce photochemical and electrochemical strategies for enzymatic CO 2 reduction. • Review recent advances in designing artificial metalloenzymes for CO 2 reduction. • Summarize designing principles of artificial metalloenzymes for CO 2 reduction. [ABSTRACT FROM AUTHOR]

Acupuncture is used to relieve symptoms, reducing recurrence, and improve the lives of patients with skin diseases. To identify, describe, and organize the available evidence on acupuncture for atopic eczema (AE) using evidence mapping of randomized controlled trials (RCTs), systematic reviews (SRs), and meta-analyses. We searched eight databases from inception to October 30, 2021, for RCTs, SRs, and meta-analyses of acupuncture for patients with AE. Two reviewers screened the papers, before extracting the data and assessing the quality of the included studies. The basic and clinical characteristics, and quality of assessment of the studies were assessed using descriptive statistics and qualitative analyses. A bubble plot was used to visualize the evidence map to indicate the relationship between the type and frequency of outcomes, the quality and overall effects of acupuncture, and the outcomes of the studies. Forty-five studies (40 RCTs, five SRs, and meta-analyses) were included. The number of publications increased rapidly after 2013 and peaked in 2019. The most frequently applied intervention was one type of acupuncture therapy. The most frequent comparison was between acupuncture and active medicine. The symptomatic outcome was the most commonly used, and the quality of the included studies was relatively low. All included studies showed a significantly better outcome in the acupuncture group compared to the control group (P < 0.05). Most outcomes in the included studies were of low or critically low quality. Several symptomatic outcomes and health-related quality of life outcomes in the included RCTs indicated moderate quality, while some symptomatic outcomes and global symptom improvement in the included SRs and meta-analyses indicated low quality. The majority of studies related to acupuncture for AE indicated promising results, but with relatively low quality; thus, further studies with more robust designs should be conducted to validate the results. [ABSTRACT FROM AUTHOR]