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Summary Water use efficiency (WUE) represents the trade‐off between carbon assimilation and water loss in plants. It remains unclear how leaf stomatal and photosynthetic traits regulate the spatial variation of leaf WUE in different natural forest ecosystems. We investigated 43 broad‐leaf tree species spanning from cold‐temperate to tropical forests in China. We quantified leaf WUE using leaf δ13C and measured stomatal traits, photosynthetic traits as well as maximum stomatal conductance (Gwmax$$ {G}_{{\mathrm{w}}_{\mathrm{max}}} $$) and maximum carboxylation capacity (Vcmax$$ {V}_{{\mathrm{c}}_{\mathrm{max}}} $$). We found that leaves in cold‐temperate forests displayed ‘fast’ carbon economics, characterized by higher leaf nitrogen, Chl, specific leaf area, and Vcmax$$ {V}_{{\mathrm{c}}_{\mathrm{max}}} $$, as an adaptation to the shorter growing season. However, these leaves exhibited ‘slow’ hydraulic traits, with larger but fewer stomata and similar Gwmax$$ {G}_{{\mathrm{w}}_{\mathrm{max}}} $$, resulting in higher leaf WUE. By contrast, leaves in tropical forests had smaller and denser stomata, enabling swift response to heterogeneous light conditions. However, this stomatal configuration increased potential water loss, and coupled with their low photosynthetic capacity, led to lower WUE. Our findings contribute to understanding how plant photosynthetic and stomatal traits regulate carbon–water trade‐offs across climatic gradients, advancing our ability to predict the impacts of climate changes on forest carbon and water cycles. [ABSTRACT FROM AUTHOR]

Increased atmospheric nitrogen (N) deposition significantly disturbs ecosystem N cycle. Although foliar interception and uptake of N deposition can provide an important alternative N supply to forest ecosystems, the mechanisms regulating foliar N uptake from wet deposition are not fully understood. Here, we selected 19 woody species with a wide range of plant traits from different functional groups and conducted a 15N isotope labelling experiment through brushing 15NH4+ and 15NO3− solution on canopy leaves. Our findings demonstrate that leaves can directly absorb N from wet deposition within a few hours. The average leaf 15N recoveries were 10% and 28% under 15NH4+ and 15NO3− treatments across species, respectively, while twig N recoveries were only 1%–7% of leaf N recoveries. Differences in foliar N uptake efficiency among species were closely associated with leaf traits but were little influenced by meteorological conditions or soil nutrient status. Specifically, plants with higher leaf N concentration, larger specific leaf area and lower wax concentration exhibited higher leaf N recovery. Our results indicated that tree canopies could directly absorb N from atmospheric deposition. We highlight the critical role of leaf traits in determining canopy foliar N uptake, which may consequently influence plant competition under elevated N deposition. Summary Statement: We conducted a 15N‐labelling experiment on canopy leaves of 19 woody species with diverse traits. We found that species with acquisitive traits had higher foliar nitrogen (N) uptake than conservative species, providing insights into the necessity of accounting foliar uptake into ecosystem N budget. [ABSTRACT FROM AUTHOR]

Summary: Forest canopies can retain nitrogen (N) from atmospheric deposition. However, most empirical and modeling studies do not consider the processing of the N deposited in the canopy.To assess whether N deposition through canopy will alter the plant's N uptake and retention, we conducted a 3‐yr mesocosm experiment by applying (15NH4)2SO4 solution to aspen sapling canopies or directly to the soil.We found that 15N‐NH4+ applied to the canopy was directly taken up by leaves. Compared with the soil N application, the canopy N application resulted in higher photosynthesis but lower N retention of the plant–soil system in the first growing season. Plant biomass, N concentration, and leaf N resorption were not significantly different between the canopy and soil N applications. The partitioning of retained 15N among plant components and soil layers was similar between the two treatments 3 yr after the N application.Our findings indicated that the canopy N processing could alter leaf N supply and photosynthesis in the short term but not N retention in the long term. Under natural conditions, the chronic N deposition could continuously refill the canopy N pool, causing a sustained increase in canopy carbon uptake. Canopy N processing needs to be considered for accurately predicting the impact of N deposition. [ABSTRACT FROM AUTHOR]

A novel coumarin Schiff base fluorescent probe ethyl 7-hydroxycoumarin-3-carboxylate-8-formaldehyde benzoyl hydrazone ( EBH) has been designed and synthesized which shows solvent dependent dual sensing, viz., recognition of Ca2+ in DMF-H2O (9∶1, V/ V) solution based on C = N isomerization, photoinduced electron transfer ( PET) inhibition and chelation-enhanced fluorescence ( CHEF) mechanism as well as detection of Zn2+ in H2O-CH3OH (9∶1, V/ V) solution by excited-state intramolecular proton transfer ( ESIPT) and CHEF processes. The structure of the probe EBH has been confirmed by single-crystal X-ray diffraction analysis. Meanwhile, the probe was also used to image intracellular Zn2+ ions in MCF-7 cells with a good performance. [ABSTRACT FROM AUTHOR]

Treatment with mesenchymal stem cells (MSCs) has been revealed to suppress CD4+ T cells and autoimmunity in both mouse models and patients with primary Sjögren syndrome (pSS); however, the underlying mechanism remains unclear. MicroRNAs (miRNAs or miRs) mediate CD4+ T cell activation, but the mechanism is not understood, particularly for CD4+ T cells treated with MSCs. Characterization of miRNAs may reveal pSS pathogenesis, guide MSC treatment and provide more personalized management options. The present study aimed to perform an miRNome analysis of quiescent and T cell receptor (TCR)-activated CD4+ T cells treated with MSCs via miRNA profiles and bioinformatics. Following 72 h of co-culture, MSCs inhibited TCR-induced CD4+ T cell activation and decreased IFN-γ levels. The numbers of aberrant miRNAs in pSS naïve (vs. healthy naïve), pSS activation (vs. pSS naïve), MSC treatment and pre-IFN-γ MSC treatment (vs. pSS activation) groups were 42, 55, 27 and 32, respectively. Gene enrichment analysis revealed that 259 pathways were associated with CD4+ T cell stimulation, and 240 pathways were associated with MSC treatment. Increased miRNA-7150 and miRNA-5096 and decreased miRNA-125b-5p and miRNA-22-3p levels in activated CD4+ T cells from patients with pSS were reversed by MSC treatment. Notably, the proliferation of CD4+ T cells and CD4+ IFN-γ+ cells, expression levels of miRNA-125b-5p and miRNA-155 in CD4+ T cells and supernatant IFN-γ secretion were associated with disease activity. miRNA may play a vital role in MSC treatment for activated CD4+ T cells. The results indicated that the expression levels of miRNA-125b-5p and miRNA-155 in TCR-activated CD4+ T cells from patients with pSS may provide insight regarding autoimmune diseases and offer a novel target for prospective treatment. Therefore, these results may be crucial in providing MSC treatment for pSS. [ABSTRACT FROM AUTHOR]

Background: Malignant pleural effusion (MPE) is prevalent among cancer patients, indicating pleural metastasis and predicting poor prognosis. However, accurately identifying MPE in clinical settings is challenging. The aim of this study was to establish an innovative nomogram-derived model based on clinical indicators and serum metal ion levels to identify MPE., Methods: From July 2020 to May 2022, 428 patients diagnosed with pleural effusion (PE) were consecutively recruited. Comprehensive demographic details, clinical symptoms, imaging data, pathological information, and laboratory results, including serum metal ion levels, were systematically collected. The nomogram was created by incorporating the most significant predictors identified through LASSO and multivariate logistic regression analysis. The predictors were assigned weighted points based on their respective regression coefficients, allowing for the calculation of a total score that corresponds to the probability of MPE. Internal validation using bootstrapping techniques assessed the nomogram's performance, including calibration, discrimination, and clinical applicability., Results: Seven key variables were identified using LASSO regression and multiple regression analysis, including dyspnea, fever, X-ray/CT compatible with malignancy, pleural carcinoembryonic antigen(pCEA), serum neuron-specific enolase(sNSE), serum carcinoembryonic antigen(sCEA), and pleural lactate dehydrogenase(pLDH). Internal validation underscored the superior performance of our model (AUC=0.940). Decision curve analysis (DCA) analysis demonstrated substantial net benefit across a probability threshold range > 1%. Additionally, serum calcium and copper levels were significantly higher, while serum zinc levels were significantly lower in MPE patients compared to benign pleural effusion (BPE) patients., Conclusion: This study effectively developed a user-friendly and reliable MPE identification model incorporating seven markers, aiding in the classification of PE subtypes in clinical settings. Furthermore, our study highlights the clinical value of serum metal ions in distinguishing malignant pleural effusion from BPE. This significant advancement provides essential tools for physicians to accurately diagnose and treat patients with MPE., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ji, Shi, Yan, Wang, Jiang, Jiang, Pan, Yu and Li.)

Treatment with mesenchymal stem cells (MSCs) has been revealed to suppress CD4 + T cells and autoimmunity in both mouse models and patients with primary Sjögren syndrome (pSS); however, the underlying mechanism remains unclear. MicroRNAs (miRNAs or miRs) mediate CD4 + T cell activation, but the mechanism is not understood, particularly for CD4 + T cells treated with MSCs. Characterization of miRNAs may reveal pSS pathogenesis, guide MSC treatment and provide more personalized management options. The present study aimed to perform an miRNome analysis of quiescent and T cell receptor (TCR)‑activated CD4 + T cells treated with MSCs via miRNA profiles and bioinformatics. Following 72 h of co‑culture, MSCs inhibited TCR‑induced CD4 + T cell activation and decreased IFN‑γ levels. The numbers of aberrant miRNAs in pSS naïve (vs. healthy naïve), pSS activation (vs. pSS naïve), MSC treatment and pre‑IFN‑γ MSC treatment (vs. pSS activation) groups were 42, 55, 27 and 32, respectively. Gene enrichment analysis revealed that 259 pathways were associated with CD4 + T cell stimulation, and 240 pathways were associated with MSC treatment. Increased miRNA‑7150 and miRNA‑5096 and decreased miRNA‑125b‑5p and miRNA‑22‑3p levels in activated CD4 + T cells from patients with pSS were reversed by MSC treatment. Notably, the proliferation of CD4 + T cells and CD4 + IFN‑γ + cells, expression levels of miRNA‑125b‑5p and miRNA‑155 in CD4 + T cells and supernatant IFN‑γ secretion were associated with disease activity. miRNA may play a vital role in MSC treatment for activated CD4 + T cells. The results indicated that the expression levels of miRNA‑125b‑5p and miRNA‑155 in TCR‑activated CD4 + T cells from patients with pSS may provide insight regarding autoimmune diseases and offer a novel target for prospective treatment. Therefore, these results may be crucial in providing MSC treatment for pSS.

Background: Xerostomia is the main manifestation from patients with Sjögren syndrome (SS). However, traditional immunosuppressive agents are nearly invalid due to complicated etiopathogenesis in salivary glands, including aberrant immune dysregulation, epithelial structure destruction, and diminished secretory function., Objective: To investigate the therapeutic effect of murine embryonic mesenchymal stem cells (ME-MSCs) on salivary glandular epithelium structure and secretory function in Sjögren-like mice., Methods: Salivary flow rate (SFR), blood glucose, and body weight was weekly monitored among treatment group, disease group, and health control group. ME-MSCs were used to treat NOD mice via tail vein injection. HE staining and transmission electron microscope was used to evaluate the structure of salivary gland epithelial cells (SGEC). TUNEL fluorescence staining and PCNA immumohistochemical staining was used to evaluate the SGEC apoptosis and proliferation. The SGEC secretory function was tested by PAS staining and amylase immumohistochemical staining., Results: ME-MSC treatment could elevate SFR, restore the acini and micromorphologies , promote the SGEC proliferation, and suppress the SGEC apoptosis in NOD mice, but not restore to that in health control group. The SGEC structure was more intact in treatment group. Mucopolysaccharide and amylase of salivary acinar cells in treatment group was better than that in disease group, although transmission electron microscopy showed secretory granules were lower than those in healthy control., Conclusion: ME-MSCs demonstrated its potential as a candidate treatment for xerostomia due to some effects on salivary flow rate in NOD mice by restoring the SGEC impairment and secretory function., Competing Interests: None., (IJCEP Copyright © 2020.)