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Rising atmospheric CO2 concentration ([CO2]) and nitrogen (N) deposition are changing plant growth, physiological characteristics and chemical compositions; however, few studies have explored such impacts in a heavy metal-contaminated environment. In this study, we conducted an open-top chamber experiment to explore the impacts of 2 years of elevated atmospheric [CO2] and N addition on the growth, physiological characteristics and chemical compositions of five subtropical tree species in a cadmium (Cd)-contaminated environment. Results showed that N addition significantly increased concentration of leaf N and protein in five tree species and also decreased payback time (PBT) and leaf carbon:nitrogen ratios and increased tree relative height growth rate (RGR-H) and basal diameter growth rate (RGR-B) in Liquidambar formosana Hance and Syzygium hainanense Chang et Miau. Elevated [CO2] increased leaf maximum photosynthetic rate (A max) and concentration of total non-structural carbohydrates and shortened PBT to offset the negative effect of Cd contamination on RGR-B in Acacia auriculiformis A. Cunn. ex Benth. The combined effects of elevated [CO2] and N addition did not exceed their separate effects on RGR-H and RGR-B in Castanopsis hystrix Hook. f. & Thomson ex A. DC. and Cinnamomum camphora (L.) presl. The addition of N significantly increased the concentration of leaf Cd by 162.1% and 338.0%, and plant Cd bio-concentration factor by 464% and 861% in C. hystrix and C. camphora , respectively, compared with only Cd addition. Among the five tree species, the decrease in PBT and the increase in A max, RGR-B and concentrations of leaf protein in response to N and Cd addition under elevated [CO2] were on average 86.7% higher in A. auriculiformis than other species, suggesting that the mitigation of the negative effects of Cd pollution by elevated [CO2] and N addition among five species was species-specific. Overall, we concluded that N addition and elevated [CO2] reduced Cd toxicity and increased the growth rate in A. auriculiformis , S. hainanense and L. formosana , while it maintained the growth rate in C. hystrix and C. camphora by differently increasing photosynthetic rate, altering the leaf chemical compositions and shortening PBT. [ABSTRACT FROM AUTHOR]

Invasive plants rapidly spread in habitats with low soil phosphorus (P) availability and have triggered a sharp decline in the diversity of native species. However, no studies have explored how widespread invasive species acclimate to low soil P availability via changing foliar P fractions, especially under elevated atmospheric CO2 concentrations ([CO2]) and nitrogen (N) deposition. Here, an open‐top chamber experiment was conducted to explore the effect of nutrient addition and elevated [CO2] on leaf traits and foliar functional P fractions (i.e., Pi, metabolite P, lipid P, nucleic acid P, and residual P) of two aggressive invasive species (Mikania micranatha and Chromolaena odorata). We found that foliar N/P ratios were more than 20, and P addition significantly increased plant biomass. Both results indicated P‐limited plant growth at our studied site. Elevated [CO2], N and N + P addition greatly increased plant biomass, photosynthetic rates, and photosynthetic P‐use efficiency (PPUE) in invasive species, but PPUE decreased with increasing P addition. Nitrogen addition slightly decreased the concentration of leaf total P, decreased foliar residual P, but increased metabolite P concentrations in invasive species. Similar changes in foliar P fractions were found under N + P addition. Phosphorus addition increased foliar P concentrations, which was strongly correlated with an increase in metabolite P concentrations in invasive species. Elevated [CO2] alleviated these effects and increased PPUE. The present results suggest that future elevated [CO2] and N deposition allow the invasive species to acclimate to low soil P availability and support their successful invasion by greatly reducing P allocation to non‐metabolite foliar P fractions (i.e., nucleic acid P and residual P) to meet their demand of metabolite P for photosynthesis and exhibit a high PPUE. [ABSTRACT FROM AUTHOR]

Introduction: Bright light therapy (BLT) is known to treat depression and sleep disorders in clinical practice, but its efficacy on poststroke depression (PSD) has not been studied. Objective: To investigate the therapeutic effects and safety of BLT combined with escitalopram oxalate (ESC) on insomnia in patients with PSD. Methods: Ischemic stroke patients with depressive symptoms and a score of ≥8 on the Hamilton Depression Scale (HAMD‐17) while meeting DSM‐IV criteria were diagnosed as having PSD. A total of 112 PSD patients with symptoms of insomnia were randomly assigned to polytherapy (BLT plus ESC) and monotherapy (ESC only) groups. Each regimen continued for 6 weeks. The primary outcomes were a change in scores on the Pittsburgh Sleep Quality Index (PSQI) and a remission rate (PSQI ≤7 at the endpoint). The secondary outcomes included changes in the HAMD‐17 and Barthel Index (BI) scores. Adverse effects were assessed by the Adverse Events Scale. Results: The endpoint assessment included 106 patients (monotherapy, 54; polytherapy, 52). The mean changes in the PSQI scores for the monotherapy and polytherapy groups were 4.85 (1.47) and 5.87 (1.72) (P = 0.001), respectively. Compared to monotherapy, polytherapy improved PSQI remission rate (71.4% vs 50.0%; χ2 = 5.390; P = 0.020), and HAMD‐17 score (6.70 [2.12] vs 4.75 [1.98]; P < 0.001). Both treatments improved BI score, with no statistical difference, and were well tolerated, with few significant differences in treatment‐associated adverse events. Conclusion: BLT combined with ESC is effective and well tolerated for the treatment of PSD‐associated insomnia. [ABSTRACT FROM AUTHOR]

(13R,17S)-ethyl secols is an important chiral intermediate used in the synthesis of contraceptive levonorgestrel. Cyberlindnera saturnus ZJPH1807 can be used as a biocatalyst for the asymmetric reduction of ethyl secondione to prepare (13R, 17S)-ethyl secols. To further enhance the carbonyl reductase activity of C. saturnus ZJPH1807,the main components of the fermentation medium including carbon source, nitrogen source, and inorganic salt were optimized using single factor experiment and response surface methodology( RSM) .The optimized medium composition was (g/L) :glucose 34. 36, yeast extract 14. 89,NH4Cl 30. 34,KH2P04 1.01. With the optimized medium, enzyme activity reached 0. 27 U/g,biomass was 6. 13 g/L, with the increase of 233. 33% and 20. 39%, respectively. The results provide a basis for the efficient synthesis of levonorgestrel by biocatalysis. [ABSTRACT FROM AUTHOR]

Objectives: To investigate whether curcumin regulates Notch signaling to cause neuroprotection and neurogenesis after focal ischemia reperfusion injury. Method: Focal ischemia reperfusion injury was modeled in rats by occluding the middle cerebral artery. These animals were given either curcumin (300 mg/kg) or corn oil (vehicle) by intraperitoneal injection starting 1 h after stroke and continuing for 7 d. In parallel, sham-operated control animals received vehicle. All animals were killed on day 12. The different treatment groups were compared in terms of neurobehavioral deficits, BrdU incorporation, and levels of doublecortin (DCX) and Notch intracellular domain (NICD) using immunohistochemistry, immunofluorescence and Western blotting. Results: Animals treated with curcumin showed significantly smaller neurobehavioral deficits than vehicle-treated animals after 3, 7, and 12 d of reperfusion (all p < 0.05). Tissue sections from curcumin-treated animals contained significantly greater numbers of BrdU-positive cells (p < 0.05) and BrdU/DCX-positive cells (p < 0.01), as well as significantly higher NICD levels (p < 0.01). Conclusion: Curcumin may protect from focal cerebral ischemia reperfusion injury as well as stimulate neurogenesis by activating the Notch signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTRice is the staple food for 1/3 of the world’s population, but soil pollution with cadmium (Cd) is harmful to rice production and human health. Therefore, how to reduce the Cd content in rice grains is a hot topic worldwide. However, so far, little is known about Cd remediation technologies for paddy soils from the perspective of patents. Therefore, a meta-analysis was performed to assess the effects of measures based on 1402 observations from 336 patents from 2011 to 2021. The spatio-temporal analysis showed that the number of patents was positively related to the general economic development of the country, but hardly related to the regional economy or the level of provincal Cd pollution. The meta-analysis showed that the overall effect of Cd reduction was slightly higher for combined technologies (59%) than for single technologies (57%). Among all technology classifications, soil applications, which are mainly based on nutritional elements, were the most commonly used technology that could reduce the Cd content in rice grains by 57%. The plant biotechnology was the most effective and could reduce Cd content in rice grains by 76%. Further analysis showed that macronutrients (calcium, phosphorus, and sulfur) were preferred in soil amendments, while micronutrients (silicon, zinc, and selenium) were preferred in foliar amendments. NRAMP5 and HMA3 were the most important genes for manipulating Cd uptake in rice, while Bacillus and Pseudomonas were the most important bacterial taxa for bioremediation of Cd. Overall, this study compiled data on Cd remediation of paddy soil from 10 years of Chinese patents, providing a theoretical basis for better production of low Cd crops and protection of human health.Patents are an indicator and promoter of theoretical innovation and technological improvement. However, little is known about Cd remediation technologies for paddy soils and rice grains from the perspective of patents. In this study, the first dataset of soil Cd remediation and rice safety production measures from the Chinese patents in the past 10 years was established. Then it evaluated the effect of each measure using meta-analysis and pointed out the future direction of research to find better solutions for Cd remediation. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is easily absorbed by rice and enters the food chain, posing a health risk to humans. Plant growth promoting bacteria (PGPB) can help the plant respond to Cd stress, but the mechanism of PGPB for Cd reduction is unclear. Therefore, this study was conducted and found inoculation with a newly isolated Pseudomonas koreensis promoted the growth of rice and reduced its Cd content. Fluorescent staining using PI and H 2 O 2 probe indicated that PGPB attenuated oxidative damage in rice. Metabolomics revealed that 59 metabolites were upregulated after inoculation, with phenylpropanoids and flavonoids being significantly activated. Spectrophotometry analysis comfirmed the content of flavonoid, lignin, phenol, glutathione, proline and the activities of antioxidant enzymes were higher in the inoculated rice than in the control. Quantitative PCR showed the expression of genes related to phenylpropanoids (OsPAL, OsC4H, Os4CL) and flavonoids (OsCHS, OsCHI) was significantly increased by PGPB, while the genes of heavy metal transporters (OsNRAMP5, OsHMA2, OsIRT1) were significantly decreased. Overall, this study provides an insight into the PGPB-mediated detoxification mechanism in rice under Cd stress and emphasizes the role of phenylpropanoids and flavonoids in the production of low-Cd rice to ensure human health., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Invasive plants rapidly spread in habitats with low soil phosphorus (P) availability and have triggered a sharp decline in the diversity of native species. However, no studies have explored how widespread invasive species acclimate to low soil P availability via changing foliar P fractions, especially under elevated atmospheric CO 2 concentrations ([CO 2 ]) and nitrogen (N) deposition. Here, an open-top chamber experiment was conducted to explore the effect of nutrient addition and elevated [CO 2 ] on leaf traits and foliar functional P fractions (i.e., Pi, metabolite P, lipid P, nucleic acid P, and residual P) of two aggressive invasive species (Mikania micranatha and Chromolaena odorata). We found that foliar N/P ratios were more than 20, and P addition significantly increased plant biomass. Both results indicated P-limited plant growth at our studied site. Elevated [CO 2 ], N and N + P addition greatly increased plant biomass, photosynthetic rates, and photosynthetic P-use efficiency (PPUE) in invasive species, but PPUE decreased with increasing P addition. Nitrogen addition slightly decreased the concentration of leaf total P, decreased foliar residual P, but increased metabolite P concentrations in invasive species. Similar changes in foliar P fractions were found under N + P addition. Phosphorus addition increased foliar P concentrations, which was strongly correlated with an increase in metabolite P concentrations in invasive species. Elevated [CO 2 ] alleviated these effects and increased PPUE. The present results suggest that future elevated [CO 2 ] and N deposition allow the invasive species to acclimate to low soil P availability and support their successful invasion by greatly reducing P allocation to non-metabolite foliar P fractions (i.e., nucleic acid P and residual P) to meet their demand of metabolite P for photosynthesis and exhibit a high PPUE., (© 2021 Scandinavian Plant Physiology Society.)