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Background: Chronic obstructive pulmonary disease (COPD) is a widespread inflammatory disease with a high mortality rate. Long noncoding RNAs play important roles in pulmonary diseases and are potential targets for inflammation intervention. Methods: The expression of small nucleolar RNA host gene 6 (SNHG6) in mouse lung epithelial cell line MLE12 with or without cigarette smoke extract (CSE) treatment was first detected using quantitative reverse‐transcription PCR. ELISA was used to evaluate the release of inflammatory cytokines (TNF‐α, IL‐1β, and IL‐6). The binding site of miR‐182‐5p with SNHG6 was predicted by using miRanda, which was verified by double luciferase reporter assay. Results: Here, we revealed that SNHG6 was upregulated in CS‐exposed MLE12 alveolar epithelial cells and lungs from COPD‐model mice. SNHG6 silencing weakened CS‐induced inflammation in MLE12 cells and mouse lungs. Mechanistic investigations revealed that SNHG6 could upregulate IκBα kinase through sponging the microRNA miR‐182‐5p, followed by activated NF‐κB signaling. The suppressive effects of SNHG6 silencing on CS‐induced inflammation were blocked by an miR‐182‐5p inhibitor. Conclusion: Overall, our findings suggested that SNHG6 regulates CS‐induced inflammation in COPD by activating NF‐κB signaling, thereby offering a novel potential target for COPD treatment. [ABSTRACT FROM AUTHOR]

Maize is a major crop essential for food and feed, but its production is threatened by various biotic and abiotic stresses. Drought is one of the most common abiotic stresses, causing severe crop yield reduction. Although several studies have been devoted to selecting drought‐tolerant maize lines and detecting the drought‐responsive mechanism of maize, the transcriptomic differences between drought‐tolerant and drought‐susceptible maize lines are still largely unknown. In our study, RNA‐seq was performed on leaves of the drought‐tolerant line W9706 and the drought‐susceptible line B73 after drought treatment. We identified 3147 differentially expressed genes (DEGs) between these two lines. The upregulated DEGs in W9706 were enriched in specific processes, including ABA signaling, wax biosynthesis, CHO metabolism, signal transduction and brassinosteroid biosynthesis‐related processes, while the downregulated DEGs were enriched in specific processes, such as stomatal movement. Altogether, transcriptomic analysis suggests that the different drought resistances were correlated with the differential expression of genes, while the drought tolerance of W9706 is due to the more rapid response to stimulus, higher water retention capacity and stable cellular environment under water deficit conditions. [ABSTRACT FROM AUTHOR]

Nitroreductase (NTR) is an important biomarker widely used to evaluate the degree of tumor hypoxia. Although a few optical methods have been reported for detecting nitroreductase at low concentration ranges, an effective strategy for nitroreductase monitoring in vivo without limits to the imaging depth is still lacking. Herein, a novel dual‐mode NIR fluorescence and 19F MRI agent, FCy7‐NO2, is proposed for imaging tumor hypoxia. We show that FCy7‐NO2 serves as not only a rapid NIR fluorescence enhanced probe for monitoring and bioimaging of nitroreductase in tumors, but also a novel 19F MR chemical shift‐sensitive contrast agent for selectively detecting nitroreductase catalyzed reduction. Notably, integrating two complementary imaging technologies into FCy7‐NO2 enables sensitive detection of nitroreductase in a broad concentration range without tissue‐depth limit. In general, this agent has a remarkable response to nitroreductase, which provides a promising method for understanding tumor evolution and its physiological role in the hypoxic microenvironment. [ABSTRACT FROM AUTHOR]

How likely genetic variations associated with environment identified in silico from genome wide association study are functionally relevant to environmental adaptation has been largely unexplored experimentally. Here we analyzed top 29 genes containing polymorphisms associated with local temperature variation (minimum, mean, maximum) among 1129 natural accessions of Arabidopsis thaliana. Their loss‐of‐function mutants were assessed for growth and stress tolerance at five temperatures. Twenty genes were found to affect growth or tolerance at one or more of these temperatures. Significantly, genes associated with maximum temperature more likely have a detect a function at higher temperature, while genes associated with minimum temperature more likely have a function at lower temperature. In addition, gene variants are distributed more frequently at geographic locations where they apparently offer an enhanced growth or tolerance for five genes tested. Furthermore, variations in a large proportion of the in silico identified genes associated with minimum or mean‐temperatures exhibited a significant association with growth phenotypes experimentally assessed at low temperature for a small set of natural accessions. This study shows a functional relevance of gene variants associated with environmental variables and supports the feasibility of the use of local temperature factors in investigating the genetic basis of temperature adaptation. SUMMARY STATEMENT: Whether or not genetic variations associated with local environmental variables are functionally relevant to environmental adaptation have not been experimentally investigated. Here we analyzed top genes with polymorphisms associated with three temperature variables of 1129 natural accessions of Arabidopsis thaliana and showed a functional relevance of these genes in temperature responses, supporting the feasibility of using in silico environment association to investigate environmental adaptation. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that is primarily caused by cigarette smoke (CS)‐induced chronic inflammation. In this study, we investigated the function and mechanism of action of the long non‐coding RNA (lncRNA) taurine‐up‐regulated gene 1 (TUG1) in CS‐induced COPD. We found that the expression of TUG1 was significantly higher in the sputum cells and lung tissues of patients with COPD as compared to that in non‐smokers, and negatively correlated with the percentage of predicted forced expiratory volume in 1 second. In addition, up‐regulation of TUG1 was observed in CS‐exposed mice, and knockdown of TUG1 attenuated inflammation and airway remodelling in a mouse model. Moreover, TUG1 expression was higher in CS extract (CSE)‐treated human bronchial epithelial cells and lung fibroblasts, whereas inhibition of TUG1 reversed CSE‐induced inflammation and collagen deposition in vitro. Mechanistically, TUG1 promoted the expression of dual‐specificity phosphatase 6 (DUSP6) by sponging miR‐145‐5p. DUSP6 overexpression reversed TUG1 knockdown‐mediated inhibition of inflammation and airway remodelling. These findings suggested an important role of TUG1 in the pathological alterations associated with CS‐mediated airway remodelling in COPD. Thus, TUG1 may be a promising therapeutic target in CS‐induced airway inflammation and fibroblast activation. [ABSTRACT FROM AUTHOR]

Purpose: CEST has become a preeminent technology for the rapid detection and grading of tumors, securing its widespread use in both laboratory and clinical research. However, many existing CEST MRI agents exhibit a sensitivity limitation due to small chemical shifts between their exchangeable protons and water. We propose a new group of CEST MRI agents, free‐base porphyrins and chlorin, with large exchangeable proton chemical shifts from water for enhanced detection. Methods: To test these newly identified CEST agents, we acquired a series of Z‐spectra at multiple pH values and saturation field strengths to determine their CEST properties. The data were analyzed using the quantifying exchange using saturation power method to quantify exchange rates. After identifying several promising candidates, a porphyrin solution was injected into tumor‐bearing mice, and MR images were acquired to assess detection feasibility in vivo. Results: Based on the Z‐spectra, the inner nitrogen protons in free‐base porphyrins and chlorin resonate from −8 to −13.5 ppm from water, far shifted from the majority of endogenous metabolites (0‐4 ppm) and Nuclear Overhauser enhancements (−1 to −3.5 ppm) and far removed from the salicylates, imidazoles, and anthranillates (5‐12 ppm). The exchange rates are sufficiently slow to intermediate (500‐9000 s−1) to allow robust detection and were sensitive to substituents on the porphyrin ring. Conclusion: These results highlight the capabilities of free‐base porphyrins and chlorin as highly upfield CEST MRI agents and provide a new scaffold that can be integrated into a variety of diagnostic or theranostic agents for biomedical applications. [ABSTRACT FROM AUTHOR]

Monitoring a drug-delivery system with an imaging modality is of great importance for detailed understanding of drug-delivery processes and for achieving optimal therapeutic effects. Here, novel fluorinated self-assembled dendrimers with a single 19F NMR signal were conveniently synthesized on multigram scales, and 19F magnetic resonance, including spectroscopy (19F NMR) and imaging (19F MRI), was used to monitor the fluorinated dendrimer-based self-assembled drug-delivery systems. It was found that 19F NMR and 19F MRI were convenient and sensitive tools to monitor the self-assembly and drugloading processes and to detect weak interactions between the drug and the drug-delivery vehicle because changes in the selfassembly profile sensitively induced corresponding 19F magnetic resonance responses. [ABSTRACT FROM AUTHOR]

A new magnetic resonance imaging (MRI) molecular sensor for hydrogen sulfide detection and imaging using the nuclear spin resonance of hyperpolarized 129Xe is developed. The designed MRI sensor employs cryptophane for NMR sensing, together with an azide group serving as a reaction site. It demonstrates a 'proof-of-concept' that a fluorescent H2S probe can be linked to a xenon-binding cryptophane and thereby converted into an MRI probe, which could provide a very generalizable template. [ABSTRACT FROM AUTHOR]

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A bimodal imaging probe FCy7‐NO2 was applied to image nitroreductase overexpressed by lung cancer in vivo, as reported by Xin Zhou and co‐workers in their Research Article (e202213495). Integrating two complementary imaging technologies into FCy7‐NO2 enables sensitive detection of nitroreductase over a broad concentration range without tissue‐depth limit. [ABSTRACT FROM AUTHOR]

With 4 figures and 2 tables Abstract The bifunctional α-amylase/subtilisin inhibitor (BASI) encoded by the Isa gene on barley chromosome 2HL could inhibit wheat α-amylase activity, thereby reducing sprouting and improving the quality of wheat. Regenerated plants were derived from immature embryo culture of hybrids of common wheat varieties 'Zhengmai 9023', 'CB037' and 'Zhongmai 16' with the wheat-barley 2H alien substitution lines 2H(2A) and 2H(2B) after callus induction, subculture and differentiation. The presence of barley 2H chromatin was detected in regenerated plants (SC1) and their selfed progeny (SC2-5) using homoeologous group 2 SSR markers from barley and further identified in selected SC4 and SC5 lines using genomic in situ hybridization with barley genomic DNA as probe and CS genomic DNA for blocking. The Isa gene from the identified SC4 and SC5 lines was also amplified using Isa-specific primers. We identified wheat-barley 2H chromosome translocation lines carring the Isa gene. [ABSTRACT FROM AUTHOR]

Hyperpolarization is one of the methods for NMR signal enhancement. NMR sensitivity can be further enhanced by combining hyperpolarization with chemical exchange saturation transfer (CEST), which termed “Hyper‐CEST”. A H2S sensor is reported that contains a cryptophane group for NMR sensing and a naphthalimide group for fluorescence sensing, together with an azide group as the reaction site. Upon reacting with H2S, the fluorescence and 129Xe NMR signal changes, which may provide a universal template for converting a fluorescence sensor into an 129Xe Hyper‐CEST MRI sensor. More information can be found in the Communication by X. Zhou, M. Liu, et al. on page 7648. [ABSTRACT FROM AUTHOR]