Search

The heat shock transcription factor (HSF) family is one of the most widely studied transcription factor families in plants; HSFs can participate in the response to various stressors, such as heat stress, high salt, and drought stress. Based on garlic transcriptome data, we screened and identified 22 garlic HSFs. The HSF proteins of garlic and Arabidopsis can be divided into three (A, B, C) subfamilies. The phylogenetic relationship, chromosome localization, sequence characteristics, conserved motifs, and promoter analysis of the HSF family were analyzed through bioinformatics methods. RT-qPCR analysis showed that the nine selected genes had different degrees of response to heat stress. In addition, we isolated and identified a class B HSF gene, AsHSFB1, from garlic variety 'Xusuan No.6'. Subsequently, the AsHSFB1 gene was overexpressed in Arabidopsis thaliana. Under heat stress, the germination rate and growth of wild-type plants were better than that of transgenic plants. Moreover, after heat treatment, the contents of peroxidase, catalase, and chlorophyll a and b of transgenic plants were lower, but the contents of malondialdehyde (MDA) and leaf conductivity were higher. Nitroblue tetrazolium (NBT) staining showed that the stained area of transgenic plant leaves was larger than that of the wild type. Further studies showed that AsHSFB1 overexpression inhibited the expression of related reverse resistance genes. These results indicate that AsHSFB1 might play a negative regulatory role in garlic resistance under high stress. Altogether, these findings provide valuable data for revealing the function of HSF genes and lay a foundation for the subsequent selection of heat-resistant garlic varieties. [ABSTRACT FROM AUTHOR]

Astragaloside IV (AST) has been confirmed to have antiasthmatic effects. However, the underline mechanism is unclear. The study aimed to explore the treatment mechanism of AST based on autophagy of memory T cells. AST treatment significantly decreased the number of T effector cells in asthma mice blood and the nude mice that received AST-treated TCMs had relieved inflammation compared with the untreated group; meanwhile, we found that AST significantly decreased the autophagy level and inhibited OX40/OX40L signal pathway of lymphocytes. The results highlighted that AST regulated autophagy to inhibit differentiation of effector T-cell phenotype. [ABSTRACT FROM AUTHOR]

We report for the first time the synthesis of a core‐shell structured composite powder with a core of Zr(Ti,Ta)C and a shell of Ti,Ta(Zr)C at 1700°C and investigate the formation mechanism for the core‐shell structure. The medium‐entropy (Ti,Zr,Ta)C ceramics with fine grains (1.1 ± 0.4 μm) and relative density of 94.8% was prepared by hot‐pressing at 2100°C. The flexural strength of (Ti,Zr,Ta)C at 1000°C (493 ± 21 MPa) was close to the room temperature (511 ± 52 MPa). As the temperature increased from 1600°C to 1800°C, the flexural strength was increased significantly, with an ultra‐high flexural strength of 725 ± 32 MPa at 1800°C. The existence of the core‐shell structure in the powder suppressed the grain growth due to the sluggish diffusion effect. The ultra‐high strength of (Ti,Zr,Ta)C ceramics was attributed to its fine microstructures, high fracture toughness, and the reinforced the grain boundary strength. [ABSTRACT FROM AUTHOR]

An abnormal level of SO2 is closely related to many diseases. Therefore, developing an effective method for the detection of SO2 in biological environments has important physiological and pathological significance. In this work, a new fluorescent probe (CA-SO2) was designed and synthesized for efficiently and specifically detecting SO2 derivatives through nucleophilic addition reaction. The novel fluorescent probe (CA-SO2) showed high selectivity, fast response time (within 50 s), and low detection limit (LOD = 75 nM). Furthermore, after adding SO2 derivatives to the probe solution, the color of the solution changes from orange to colorless, which allows "naked eye" detection for SO2. Moreover, the probe has a large Stokes shift (129 nm) and excellent biocompatibility. The probe has been successfully applied to the detection of SO2 derivatives in living cells and zebrafish. [ABSTRACT FROM AUTHOR]

Background: Our recent studies have identified that the red nucleus (RN) dual-directionally modulates the development and maintenance of mononeuropathic pain through secreting proinflammatory and anti-inflammatory cytokines. Here, we further explored the action of red nucleus IL-33 in the early development of mononeuropathic pain.Methods: In this study, male rats with spared nerve injury (SNI) were used as mononeuropathic pain model. Immunohistochemistry, Western blotting, and behavioral testing were used to assess the expressions, cellular distributions, and actions of red nucleus IL-33 and its related downstream signaling molecules.Results: IL-33 and its receptor ST2 were constitutively expressed in the RN in naive rats. After SNI, both IL-33 and ST2 were upregulated significantly at 3 days and peaked at 1 week post-injury, especially in RN neurons, oligodendrocytes, and microglia. Blockade of red nucleus IL-33 with anti-IL-33 neutralizing antibody attenuated SNI-induced mononeuropathic pain, while intrarubral administration of exogenous IL-33 evoked mechanical hypersensitivity in naive rats. Red nucleus IL-33 generated an algesic effect in the early development of SNI-induced mononeuropathic pain through activating NF-κB, ERK, p38 MAPK, and JAK2/STAT3, suppression of NF-κB, ERK, p38 MAPK, and JAK2/STAT3 with corresponding inhibitors markedly attenuated SNI-induced mononeuropathic pain or IL-33-evoked mechanical hypersensitivity in naive rats. Red nucleus IL-33 contributed to SNI-induced mononeuropathic pain by stimulating TNF-α expression, which could be abolished by administration of inhibitors against ERK, p38 MAPK, and JAK2/STAT3, but not NF-κB.Conclusions: These results suggest that red nucleus IL-33 facilitates the early development of mononeuropathic pain through activating NF-κB, ERK, p38 MAPK, and JAK2/STAT3. IL-33 mediates algesic effect partly by inducing TNF-α through activating ERK, p38 MAPK and JAK2/STAT3. [ABSTRACT FROM AUTHOR]

Summary: Lysine is the main limiting essential amino acid (EAA) in the rice seeds, which is a major energy and nutrition source for humans and livestock. In higher plants, the rate‐limiting steps in lysine biosynthesis pathway are catalysed by two key enzymes, aspartate kinase (AK) and dihydrodipicolinate synthase (DHDPS), and both are extremely sensitive to feedback inhibition by lysine. In this study, two rice AK mutants (AK1 and AK2) and five DHDPS mutants (DHDPS1–DHDPS5), all single amino acid substitution, were constructed. Their protein sequences passed an allergic sequence‐based homology alignment. Mutant proteins were recombinantly expressed in Escherichia coli, and all were insensitive to the lysine analog S‐(2‐aminoethyl)‐l‐cysteine (AEC) at concentrations up to 12 mm. The AK and DHDPS mutants were transformed into rice, and free lysine was elevated in mature seeds of transgenic plants, especially those expressing AK2 or DHDPS1, 6.6‐fold and 21.7‐fold higher than the wild‐type (WT) rice, respectively. We then engineered 35A2D1L plants by simultaneously expressing modified AK2 and DHDPS1, and inhibiting rice LKR/SDH (lysine ketoglutaric acid reductase/saccharopine dehydropine dehydrogenase). Free lysine levels in two 35A2D1L transgenic lines were 58.5‐fold and 39.2‐fold higher than in WT and transgenic rice containing native AK and DHDPS, respectively. Total free amino acid and total protein content were also elevated in 35A2D1L transgenic rice. Additionally, agronomic performance analysis indicated that transgenic lines exhibited normal plant growth, development and seed appearance comparable to WT plants. Thus, AK and DHDPS mutants may be used to improve the nutritional quality of rice and other cereal grains. [ABSTRACT FROM AUTHOR]

WRKY transcription factors (TFs) are primarily involved in regulating the response of plants to different types of abiotic stress and related physiological processes. WRKY genes have yet to be characterized in garlic (Allium sativum L.), which is in the family Alliaceae. Here, 78 WRKY TFs were identified based on the garlic transcriptome and genome. They were divided into seven subfamilies based on Arabidopsis thaliana WRKY domains. Cis-element analysis revealed that the WRKY family members have ABRE and MBS cis-response elements that respond to salt stress, gibberellins, and drought stress. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis revealed that the expression of nine WRKY genes was induced under heat and salt stress. [ABSTRACT FROM AUTHOR]

We previously reported that interleukin (IL)‐6 in the red nucleus (RN) is involved in the maintenance of neuropathic pain induced by spared nerve injury (SNI), and exerts a facilitatory effect via Janus‐activated kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) and extracellular signal‐regulated kinase (ERK) signal transduction pathways. The present study aimed at investigating the roles of tumor necrosis factor‐α (TNF‐α) and IL‐1β in RN IL‐6‐mediated maintenance of neuropathic pain and related signal transduction pathways. Being similar to the elevation of RN IL‐6 three weeks after SNI, increased protein levels of both TNF‐α and IL‐1β were also observed in the contralateral RN three weeks after the nerve injury. The upregulations of TNF‐α and IL‐1β were closely correlative with IL‐6 and suppressed by intrarubral injection of a neutralizing antibody against IL‐6. Administration of either the JAK2 antagonist AG490 or the ERK antagonist PD98059 to the RN of rats with SNI remarkably increased the paw withdrawal threshold (PWT) and inhibited the up‐regulations of local TNF‐α and IL‐1β. Further experiments indicated that intrarubral injection of exogenous IL‐6 in naive rats apparently lowered the PWT of the contralateral hindpaw and boosted the local expressions of TNF‐α and IL‐1β. Pretreatment with AG490 could block IL‐6‐induced tactile hypersensitivity and suppress the up‐regulations of both TNF‐α and IL‐1β. However, injection of PD98059 in advance only inhibited the upregulation of IL‐1β, but not TNF‐α. These findings indicate that RN IL‐6 mediates the maintenance of neuropathic pain by inducing the productions of TNF‐α and IL‐1β. IL‐6 induces the expression of TNF‐α through the JAK2/STAT3 pathway, and the production of IL‐1β through the JAK2/STAT3 and ERK pathways. [ABSTRACT FROM AUTHOR]

Summary: Purple carrots, the original domesticated carrots, accumulate highly glycosylated and acylated anthocyanins in root and/or petiole. Previously, a quantitative trait locus (QTL) for root‐specific anthocyanin pigmentation was genetically mapped to chromosome 3 of carrot. In this study, an R2R3‐MYB gene, namely DcMYB113, was identified within this QTL region. DcMYB113 expressed in the root of 'Purple haze', a carrot cultivar with purple root and nonpurple petiole, but not in the roots of two carrot cultivars with a purple root and petiole (Deep purple and Cosmic purple) and orange carrot 'Kurodagosun', which appeared to be caused by variation in the promoter region. The function of DcMYB113 from 'Purple haze' was verified by transformation in 'Cosmic purple' and 'Kurodagosun', resulting in anthocyanin biosynthesis. Transgenic 'Kurodagosun' carrying DcMYB113 driven by the CaMV 35S promoter had a purple root and petiole, while transgenic 'Kurodagosun' expressing DcMYB113 driven by its own promoter had a purple root and nonpurple petiole, suggesting that root‐specific expression of DcMYB113 was determined by its promoter. DcMYB113 could activate the expression of DcbHLH3 and structural genes related to anthocyanin biosynthesis. DcUCGXT1 and DcSAT1, which were confirmed to be responsible for anthocyanins glycosylation and acylation, respectively, were also activated by DcMYB113. The WGCNA identified several genes co‐expressed with anthocyanin biosynthesis and the results indicated that DcMYB113 may regulate anthocyanin transport. Our findings provide insight into the molecular mechanism underlying root‐specific anthocyanin biosynthesis and further modification in carrot and even other root crops. [ABSTRACT FROM AUTHOR]

Celery (Apium graveolens L.) is one of the most important vegetables in the Apiaceae family, rich in nutrients and widely grown around the world. bZIP transcription factors family plays an important role in the transcription regulation of plant growth and development, as well as adaptation to the external environment. In this paper, 62 bZIP family transcription factors were screened and identified based on the whole genome sequence of celery. The bZIP proteins of celery and Arabidopsis thaliana were divided into 10 subfamilies according to the phylogenetic tree. Phylogenetic and evolutionary analysis showed that the number of bZIP family members gradually expanded from lower plants to higher plants during the long evolution process. Based on the homology of celery and A. thaliana bZIP genes, the interaction network between celery bZIP transcription factors and other proteins in the genome was constructed, and the correlation data of protein interaction were also obtained. The expression profiles of 12 selected AgbZIP genes were detected and analyzed under abiotic stress treatments and different tissues using RT-qPCR. The results showed that AgbZIP can respond to high temperature, low temperature, drought, and high salt stress. [ABSTRACT FROM AUTHOR]

• A novel sequential solution strategy is proposed for a type of benchmark 3D IHCP. • A new time-space adaptive mesh refinement strategy is developed. • Different heat-flux patterns of practical significance are investigated. • The IHCPs for plain and micro/nano structured surfaces in pool boiling are studied. • The method is successfully applied in a single-bubble nucleate boiling experiment. Inverse heat conduction problems appear in a variety of applications in industry and academia. Due to their mathematical challenges, they have been studied extensively over the last decades. Nevertheless, the solution of three dimensional transient inverse heat conduction problems are still computationally expensive. Commonly used solution approaches include the regularization-based approaches such as Tikhonov regularization or iterative regularization that result in formulating and solving optimization problems. A radically different solution approach is presented in this paper to provide efficient solutions of three dimensional transient inverse heat conduction problems on thin-plates that are used very often in industrial applications. Instead of solving optimization problems subject to constraints given in terms of three dimensional partial differential equations, the suggested approach transforms the inverse problem into an easy-to-solve direct problem that only needs the reconstruction of a Dirichlet boundary condition. This yields an approximated solution. Furthermore, a new time-space adaptive mesh refinement strategy is proposed to further reduce computational effort at an acceptable level of estimation precision. The accuracy and efficiency of the proposed sequential approach as well as the time-space adaptive mesh refinement strategy are validated by four representative case studies arising from practice. Estimation results with experimental data are also presented. The current work is considered as an important step forward towards the efficient solution of transient three dimensional inverse heat conduction problems, which is particularly useful for developing heat-flux soft sensors in practical problems arising from different fields such as pool boiling, falling films and steelmaking. [ABSTRACT FROM AUTHOR]

Rice is the primary staple food for half of the world's population but is low in lysine content. Previously, we developed transgenic rice with enhanced free lysine content in rice seeds (lysine-rich rice), which was shown safe for consumption and improved the growth in rats. However, the effects of lysine-rich rice on skeletal growth and development remained unknown. In this study, we hypothesized that lysine-rich rice improved skeletal growth and development in weaning rats. Male weaning Sprague–Dawley rats received lysine-rich rice (HFL) diet, wild-type rice (WT) diet, or wild-type rice with various contents of lysine supplementation diet for 70 days. Bone microarchitectures were examined by microcomputed tomography, bone strength was investigated by mechanical test, and dynamics of bone growth were examined by histomorphometric analysis. In addition, we explored the molecular mechanism of lysine and skeletal growth through biochemical testing of growth hormone, bone turnover marker, and amino acid content of rat serum analysis, as well as in a cell culture system. Results indicated that the HFL diet improved rats' bone growth, strength, and microarchitecture compared with the WT diet group. In addition, the HFL diet increased the serum essential amino acids, growth hormone (insulin-like growth factor-1), and bone formation marker concentrations. The cell culture model showed that lysine deficiency reduced insulin-like growth factor-1 and Osterix expression, Akt/mammalian target of rapamycin signaling, and matrix mineralization, and inhibited osteoblast differentiation associated with bone growth. Our findings showed that lysine-rich rice improved skeletal growth and development in weaning rats. A further increase of rice lysine content is highly desirable to fully optimize bone growth and development. A rat-feeding study was performed. Bone strength and quality were then assessed, and the molecular mechanism for bone growth was evaluated. Lysine-rich rice diets improved the growth of rats. Lysine induced serum IGF-1 expression and activated the downstream signaling pathway. The active signaling and higher intracellular amino acid pool led to subsequent bone formation. Abbreviations: CT, computed tomography; IGF-1, insulin-like growth factor-1; mTOR, mammalian target of rapamycin; SD, Sprague–Dawley. [Display omitted] [ABSTRACT FROM AUTHOR]

To identify the short-lived, highly-active iron intermediate generated in situ for water oxidation, we describe here a new complex 1 by subtle modulation of the TPA ligand and succeed in capturing the high-valent FeIV(O) species, which is responsible for the O–O bond formation and oxygen evolution with higher efficiency. [ABSTRACT FROM AUTHOR]

Lysine is considered to be the first essential amino acid in rice. An elite H igh- F ree- L ysine transgenic line HFL1 was previously produced by metabolic engineering to regulate lysine metabolism. In this study, a 90-day toxicology experiment was undertaken to investigate the potential health effect of feeding different doses of HFL1 rice to Sprague-Dawley rats. During the trial, body weight gain, food consumption and food efficiency were recorded, and no adverse effect was observed in rats fed transgenic (T) rice diets compared with non-transgenic (N) or control diets. At both midterm and final assessments, hematological parameters and serum chemistry were measured, and organ weights and histopathology were examined at the end of the trial. There was no diet-related difference in most hematological or serum chemistry parameters or organ weights between rats fed the T diets and those fed the N or control diets. Some parameters were found to differ between T groups and their corresponding N and/or control groups, but no adverse histological effect was observed. Taken together, the data from the current trial demonstrates that high lysine transgenic rice led to no adverse effect in Sprague-Dawley rats given a diet containing up to 70% HFL1 rice in 90 days. [ABSTRACT FROM AUTHOR]

The first example of a catalytic asymmetric formal [4+1] annulation reaction between sulfur ylides and in situ generated ortho-quinone methides (o-QMs) is reported in this work. A C2-symmetric chiral urea was identified to be the best H bonding catalyst, affording a wide range of chiral 2,3-dihydrobenzofurans in high yields and moderate enantioselectivities [70-98 % yields, up to 89:11 e.r. (enantiomeric ratio)]. [ABSTRACT FROM AUTHOR]

Photocatalysis enables the cascade reactions of indoles and CBr4 in MeOH through a C(sp2)H functionalization/methanolysis sequence. The title reaction provides an efficient access to indole 2- and 3-carboxylates in a single operation (no preinstallation of protecting as well as directing groups was required) with good yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Aims Alterations in the expression of several long non-coding RNAs (lnc RNAs) have been found in primary nasopharyngeal carcinoma ( NPC). However, the effect of lnc RNA expression on primary NPC as well as the molecular mechanism of lnc RNA remains vague. This study was to identify differentially expressed lnc RNAs involved in NPC on a genome-wide scale and predict their potential functions. Methods and results Using high-throughput microarray with 30 586 lnc RNA and 26 109 mRNA probes, 856 lnc RNAs and 767 mRNAs were expressed differentially between NPC and chronic nasopharyngitis tissues. Bioinformatic analysis (clustering analysis, gene ontology analysis and pathway analysis) was used for further research. Differentially expressed lnc RNAs were subgrouped into three types and differentially expressed mRNAs were clustered into 28 pathways. The first coexpression network analysis revealed that 46 lnc RNAs interacting with three mRNAs involved the Janus kinase-signal transducer and activator of transcription ( JAK- STAT) signalling pathway. Quantitative real-time polymerase chain reaction ( PCR) verified 11 up- and down-regulated lnc RNAs and eight mRNAs in NPC. The second coexpression network analysis showed that 23 significantly aberrantly expressed mRNAs interacted with three validated lncRNAs. Conclusions This study could provide new insight into the molecular mechanisms of lnc RNAs and their potential role in NPC for further study. These differentially expressed lnc RNAs may act as novel biomarkers and therapeutic targets for NPC. [ABSTRACT FROM AUTHOR]

The highly enantioselective synthesis of densely functionalized 2,3-indoline-cyclobutanes by means of chiral gold catalysis is presented. Intermolecular formal [2+2]-cycloaddition reactions between substituted indoles and allenamides enabled direct access to methylenecyclobutane-fused indolines, featuring two consecutive quaternary stereogenic centers with excellent stereochemical control (dr ＞ 20 : 1, ee up to 99%). [ABSTRACT FROM AUTHOR]

Abstract: A direct and efficient synthesis of 2,3-unsubstituted 1-acylpyrrolo[2,1-a]isoquinolines is described. The 1,3-dipolar cycloaddition of stabilized isoquinolinium N-ylides with vinyl sulfonium salts features simple experimental procedures, mild conditions, and moderate to good yields. [Copyright &y& Elsevier]

Get asymmetric! Asymmetric [4+1] annulation of sulfur ylides and N‐(ortho‐chloromethyl)aryl amides allowed the formation of the desired cycloadduct with moderate to high yields and enantioselectivities (see scheme). The described strategy, taking advantage of chiral sulfur ylides, represents a direct procedure to access chiral 2‐substituted indolines. [ABSTRACT FROM AUTHOR]

Immobilizing molecular catalysts on electro‐conductive supports (for example, multi‐walled carbon nanotubes, CNTs) represent a promising way to well‐defined catalyst/support interfaces, which has shown appreciable performance for catalytic transformation. However, their full potential is far from achieved due to insufficient utilization of the intrinsic activity for each immobilized molecular catalyst, especially at loadings that should allow decent current densities. In the present work, we discover host–guest interaction between tetra‐crown ether substituted cobalt phthalocyanine and metal ions, for example K+ ions, not only eliminate catalyst aggregation at immobilization procedures but also reinforce catalyst/support interactions by additional electrostatic attractions under operational conditions. Through simple dip‐coating procedures, a successful single molecular dispersion is achieved. Such a catalyst/electrode interface is stable and can selectively catalyze CO2‐to‐CO conversion with Faradaic efficiency over 96%. Importantly, this interface maintains an almost unchanged turnover frequency (TOF) across all loading conditions, implying a full utilization of the intrinsic activity of supported molecular catalysts. Therefore, a simultaneous achievement of high TOF and high current density (TOF of 111 s−1 at 38 mA cm−2) is achieved, in an aqueous H‐type electrolyzer at an overpotential of 570 mV. [ABSTRACT FROM AUTHOR]

3-Isothiocyanato oxindoles are a class of important building blocks which have been widely used in the synthesis of structurally diverse enantioenriched spirooxindoles. In this short review, it is attempted to cover the recent synthetic aspects of 3-isothiocyanato oxindoles participated cascade cyclizations in the last few years (i.e., from 2017 to 2022), with an emphasis on formal [3+2] cycloaddition reactions. 1 Introduction 2 Organocatalyzed Formal [3+2] Cycloaddition of 3-Isothiocyanato Oxindoles 3 Lewis Acid Catalyzed Formal [3+2] Cycloaddition of 3-Isothiocyanato Oxindoles 4 Conclusions [ABSTRACT FROM AUTHOR]

As a traditional Chinese medicine, Lianhua Qingwen capsules have been widely used to treat Coronavirus Disease 2019 (COVID-19). This study was aimed to demonstrate the association between treatment with Lianhua Qingwen capsules and the clinical outcomes of hospitalized patients with COVID-19. This retrospective study was conducted at four hospitals in Central China. Data of hospitalized COVID-19 patients were collected between December 19, 2019 and April 26, 2020. Based on whether Lianhua Qingwen capsules were used, patients were classified into Lianhua Qingwen and non-Lianhua Qingwen (control) groups. To control for confounding factors, we used conditional logistic regression in a propensity-score matched (PSM) cohort (1 : 1 balanced), as well as logistic regression without matching as sensitivity analysis. A total of 4918 patients were included, 2760 of whom received Lianhua Qingwen capsules and 2158 of whom did not. In the PSM model, after adjusting for confounders, the in-hospital mortality was similar between the Lianhua Qingwen group and the control group (6.8% vs. 3.3%, adjusted OR, 0.66 [95% CI, 0.38-1.15], p = 0.138). The negative conversion rate of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection was higher in the Lianhua Qingwen group (88.3% vs. 96.1%, adjusted OR, 4.02 [95% CI, 2.58-6.25], p < 0.001). The incidence of acute liver injury was comparable between the two groups (14.0% vs. 11.5%, adjusted OR: 0.85 [95% CI, 0.71-1.02], p = 0.083), and the incidence of acute kidney injury was lower in the Lianhua Qingwen group (5.3% vs. 3.0%, adjusted OR: 0.71 [95% CI, 0.50-1.00], p = 0.048). Treatment with Lianhua Qingwen capsules was not significantly associated with in-hospital mortality in COVID-19 patients. In the Lianhua Qingwen group, the negative conversion rate of SARS-CoV-2 infection was higher and the incidence of acute kidney injury was lower than in the control group. [ABSTRACT FROM AUTHOR]

The development of a near-infrared fluorophore with excellent fluorescence performance, a large Stokes shift, and good biocompatibility has become a focus in the field of fluorescence imaging in recent years. Based on quantum chemistry calculations and reasonable molecular design strategies, a new NIR fluorophore was developed and characterized by simple synthesis, easy structural modification, and a large Stokes shift (105 nm). Furthermore, two new "activatable" fluorescent probes QN-Cys and QN-DNP were synthesized using a simple structural modification. The probe QN-Cys can recognize Cys with high sensitivity (LOD = 128 nM) and high selectivity, and its fluorescence intensity has a good linear relationship with the Cys concentration in the range of 5–35 μM. Furthermore, probe QN-Cys can effectively distinguish Cys from Hcy and GSH, and was successfully applied to the detection and imaging of Cys in human serum, cells, and zebrafish. The probe QN-DNP showed a good specific and sensitive (LOD = 78 nM) fluorescence response to thiophenol, and its fluorescence intensity has a good linear relationship with the thiophenol concentration in the range of 5–30 μM. Furthermore, it was successfully applied to detect thiophenol in real water samples with good recoveries (97–102%), and image thiophenol in living cells, zebrafish and mice. Notebly, the QN-DNP probe could be applied to visualize the distribution of thiophenol in the mice. [Display omitted] • Reasonably designed a fluorophore QN-OH with NIR fluorescence properties (λem = 685 nm) and large Stokes shift (105 nm). • Probe QN-Cys can be used to discriminate detection of Cys from Hcy and GSH, imaging Cys in cells and zebrafish. • Probe QN-DNP was used for detection of PhSH in water samples, and imaging PhSH in living cells, zebrafishs and mice. [ABSTRACT FROM AUTHOR]

Background: R2R3-MYB transcription factors belong to one of the largest gene subfamilies in plants, and they are involved in diverse biological processes. However, the role of R2R3-MYB transcription factor subfamily genes in the response of rice (Oryza sativa L.) to salt stress has been rarely reported. Results: In this study, we performed a genome-wide characterization and expression identification of rice R2R3-MYB transcription factor subfamily genes. We identified a total of 117 R2R3-MYB genes in rice and characterized their gene structure, chromosomal location, and cis-regulatory elements. According to the phylogenetic relationships and amino acid sequence homologies, the R2R3-MYB genes were divided into four groups. qRT-PCR of the R2R3-MYB genes showed that the expression levels of 10 genes significantly increased after 3 days of 0.8% NaCl treatment. We selected a high expression gene OsMYB2-115 for further analysis. OsMYB2-115 was highly expressed in the roots, stem, leaf, and leaf sheath. OsMYB2-115 was found to be localized in the nucleus, and the yeast hybrid assay showed that OsMYB2-115 has transcriptional activation activity. Conclusion: This result provides important information for the functional analyses of rice R2R3-MYB transcription factor subfamily genes related to the salt stress response and reveals that OsMYB2-115 may be an important gene associated with salt tolerance in rice. [ABSTRACT FROM AUTHOR]

Aza- ortho -quinone methides are important reactive intermediates that have found broad applications in synthetic chemistry. Recently, 1,4-elimination of ortho -chloromethyl aniline derivatives has emerged as a novel, powerful and convenient method for aza- ortho -quinone methide generation. This review will highlight the recent applications of aza- ortho -quinone methide precursors in annulation reactions to access various biologically important nitrogen-containing heterocycles. The general mechanisms are briefly discussed as well. 1 Introduction 2 [4+n] Annulation Reactions Using ortho -Chloromethyl Anilines as Aza- ortho -Quinone Methide Precursors 2.1 [4+2] Annulation Reactions 2.2 [4+1] Annulation Reactions 2.3 [4+3] Annulation Reactions 3 Conclusion and Perspective [ABSTRACT FROM AUTHOR]

Diazo compounds have proven to be a useful class of carbenes or metal carbenoids sources under thermal, photochemical, or metal-catalyzed conditions, which can subsequently undergo a wide range of synthetically important transformations. Recently, asymmetric photocatalysis has provoked increasing research interests, and great advances have been made in this discipline towards the synthesis of optically enriched compounds. In this context, the past two decades have been the most productive period in the developments of enantioselective photochemical reactions of diazo compounds due to a better understanding of the reactivities of diazo compounds and the emergence of new catalytic modes, as well as easier access to and treatment of stabilized diazo compounds. This review highlights these impressive achievements according to the reaction type, and the general mechanisms and stereochemical inductions are briefly discussed as well. [ABSTRACT FROM AUTHOR]

Medium‐entropy (Ti,Zr,Hf)C ceramics were prepared by hot pressing a dual‐phase medium‐entropy carbide powder with low oxygen content (0.45 wt%). The results demonstrate that the medium‐entropy (Ti,Zr,Hf)C ceramics sintered at 2100°C had a relative density of 99.2% and an average grain size of 1.9 ± 0.6 μm. The flexural strength of (Ti,Zr,Hf)C carbide ceramics at room temperature was 579 ± 62 MPa. With an increase in temperature to 1600°C, the flexural strength showed an increase up to 619 ± 57 MPa, and had no significant degradation even up to 1800°C. The high‐temperature flexural strengths of (Ti,Zr,Hf)C were obviously higher than those of the monocarbide ceramics (TiC, ZrC, and HfC). The primary strengthening mechanism in (Ti,Zr,Hf)C could be attributed to the high lattice parameter mismatch effects between TiC and ZrC, which not only inhibited the fast grain coarsening of (Ti,Zr,Hf)C ceramics, but also increased the grain‐boundary strength of the obtained ceramics. [ABSTRACT FROM AUTHOR]

The accurate identification of forest tree species is the basis for the utilization and protection of forest resources. In this study, we collected hyperspectral data on 3287 leaves from seven typical tree species in the Caohai Nature Reserve and Huaxi District, Guizhou Province, China. The Savitzky–Golay smoothing, baseline, normalize, standardized normal variable, and moving average methods were used to preprocess the original spectral reference after removing the abnormal values, and then the dimension was reduced by principal component analysis. Finally, the reduced data were classified by support vector machine with the linear, polynomial, radial basis function, and Sigmoid kernel functions. The results show the following: (1) the principal component analysis + support vector machine method is feasible for tree species identification, however, the recognition results of different preprocessing methods, different combinations of principal components, and different support vector machine classification methods are quite different; (2) the best combination is 20 principal components + the normalize + linear support vector machine model, achieving a classification overall accuracy of 98.97%. [ABSTRACT FROM AUTHOR]

Summary: Starch accounts for up to 90% of the dry weight of rice endosperm and is a key determinant of grain quality. Although starch biosynthesis enzymes have been comprehensively studied, transcriptional regulation of starch‐synthesis enzyme‐coding genes (SECGs) is largely unknown. In this study, we explored the role of a NAC transcription factor, OsNAC24, in regulating starch biosynthesis in rice. OsNAC24 is highly expressed in developing endosperm. The endosperm of osnac24 mutants is normal in appearance as is starch granule morphology, while total starch content, amylose content, chain length distribution of amylopectin and the physicochemical properties of the starch are changed. In addition, the expression of several SECGs was altered in osnac24 mutant plants. OsNAC24 is a transcriptional activator that targets the promoters of six SECGs; OsGBSSI, OsSBEI, OsAGPS2, OsSSI, OsSSIIIa and OsSSIVb. Since both the mRNA and protein abundances of OsGBSSI and OsSBEI were decreased in the mutants, OsNAC24 functions to regulate starch synthesis mainly through OsGBSSI and OsSBEI. Furthermore, OsNAC24 binds to the newly identified motifs TTGACAA, AGAAGA and ACAAGA as well as the core NAC‐binding motif CACG. Another NAC family member, OsNAP, interacts with OsNAC24 and coactivates target gene expression. Loss‐of‐function of OsNAP led to altered expression in all tested SECGs and reduced the starch content. These results demonstrate that the OsNAC24‐OsNAP complex plays key roles in fine‐tuning starch synthesis in rice endosperm and further suggest that manipulating the OsNAC24‐OsNAP complex regulatory network could be a potential strategy for breeding rice cultivars with improved cooking and eating quality. [ABSTRACT FROM AUTHOR]

A visible‐light‐induced cascade radical cyclization of aroyl chlorides with 2‐(allyloxy)‐benzaldehyde derivatives has been developed. The method takes advantages of unactivated C=C bonds as the acyl radical acceptors and offers a mild and green approach for the synthesis of 1,4‐diketones bearing biologically important chroman‐4‐one skeletons with moderate to good yields. [ABSTRACT FROM AUTHOR]

A photoredox-mediated carboxylation of heterocycles and even electron-rich benzenes is described. [ABSTRACT FROM AUTHOR]

High‐valent iron‐oxo species are appealing for conducting O−O bond formation for water oxidation reactions. However, their high reactivity poses a great challenge to the dissection of their chemical transformations. Herein, we introduce an electron‐rich and oxidation‐resistant ligand, 2‐[(2,2′‐bipyridin)‐6‐yl]propan‐2‐ol to stabilize such fleeting intermediates. Advanced spectroscopies and electrochemical studies demonstrate a high‐valent FeV(O) species formation in water. Combining kinetic and oxygen isotope labelling experiments and organic reactions indicates that the FeV(O) species is responsible for O−O bond formation via water nucleophilic attack under the real catalytic water oxidation conditions. [ABSTRACT FROM AUTHOR]

High‐valent iron‐oxo species are appealing for conducting O−O bond formation for water oxidation reactions. However, their high reactivity poses a great challenge to the dissection of their chemical transformations. Herein, we introduce an electron‐rich and oxidation‐resistant ligand, 2‐[(2,2′‐bipyridin)‐6‐yl]propan‐2‐ol to stabilize such fleeting intermediates. Advanced spectroscopies and electrochemical studies demonstrate a high‐valent FeV(O) species formation in water. Combining kinetic and oxygen isotope labelling experiments and organic reactions indicates that the FeV(O) species is responsible for O−O bond formation via water nucleophilic attack under the real catalytic water oxidation conditions. [ABSTRACT FROM AUTHOR]

A Cu(ii) coordination polymer, [Cu(tza)2]n (Htza, tetrazole-1-acetic acid), was investigated as an efficient water oxidation catalyst in the well-established Ru(bpy)32+/S2O82− (bpy = 2,2′-bipyridine) photocatalytic system. The turnover frequency (TOF) was measured to be 1.68 s−1, which is the highest among all reported copper-based photocatalytic water oxidation systems. [ABSTRACT FROM AUTHOR]

Highly enantioenriched spiro-epoxyoxindoles are obtained from isatins and chiral sulfur ylides generated in situ from camphor-derived sulfonium salts. [ABSTRACT FROM AUTHOR]

Asymmetric [4 + 1] annulation of axial chiral sulfur ylides (I) and N-(ortho-chloromethyl)aryl amides represents a direct procedure to access chiral 2-substituted indolines. [ABSTRACT FROM AUTHOR]

The title approach is advantageous with regards to simple experimental procedure and mild reaction conditions. [ABSTRACT FROM AUTHOR]

α-Fetoprotein (AFP)-producing gastric carcinoma (AFPGC) is a rare subtype of gastric cancer (GC) with controversial classification methods. Hepatoid adenocarcinoma of the stomach (HAS) is another rare subtype of GC. Its definition intersects with that of AFPGC, but it is much rarer. The present report describes the case of an elderly patient with GC and AFPGC and HAS features in a serum test and pathology, respectively, and proposes a new classification of GC subtypes based on histological and AFP-producing features. A 75-year-old woman presented with a history of polydipsia and polyuria for over a decade and dizziness for 1 day. Serum AFP levels gradually elevated from 183.70 to 397.70 ng/ml in 1 month after the patient's first clinic visit. Subsequent pathological findings from endoscopic biopsy samples confirmed a hepatoid focus with positive immunohistochemical staining for AFP. The patient underwent a laparoscopic-assisted radical total gastrectomy and esophagojejunal Roux-en-Y anastomosis, and the serum AFP levels decreased to the normal range after the surgery. The present case indicates the diagnostic value of both the serum AFP level and pathological examinations in the diagnosis of AFPGC and HAS, and also highlights the contemporary circumstances of the vague classification based on different criteria for these two subtypes. Furthermore, the present report proposes a new classification considering both histological and AFP-producing features (using both serum biomarkers and immunohistochemistry tests) to cover all cases encompassed by AFPGC and HAS under all definition methods. This new method would give more precise diagnoses and add value to the subsequent treatment decision-making. [ABSTRACT FROM AUTHOR]

Our previous study has verified that activation of group Ⅰ metabotropic glutamate receptors (mGluRⅠ) in the red nucleus (RN) facilitate the development of neuropathological pain. Here, we further discussed the functions and possible molecular mechanisms of red nucleus mGluR Ⅱ (mGluR2 and mGluR3) in the development of neuropathological pain induced by spared nerve injury (SNI). Our results showed that mGluR2 and mGluR3 both were constitutively expressed in the RN of normal rats. At 2 weeks post-SNI, the protein expression of mGluR2 rather than mGluR3 was significantly reduced in the RN contralateral to the nerve lesion. Injection of mGluR2/3 agonist LY379268 into the RN contralateral to the nerve injury at 2 weeks post-SNI significantly attenuated SNI-induced neuropathological pain, this effect was reversed by mGluR2/3 antagonist EGLU instead of selective mGluR3 antagonist β-NAAG. Intrarubral injection of LY379268 did not alter the PWT of contralateral hindpaw in normal rats, while intrarubral injection of EGLU rather than β-NAAG provoked a significant mechanical allodynia. Further studies indicated that the expressions of nociceptive factors TNF-α and IL-1β in the RN were enhanced at 2 weeks post-SNI. Intrarubral injection of LY379268 at 2 weeks post-SNI significantly suppressed the overexpressions of TNF-α and IL-1β, these effects were reversed by EGLU instead of β-NAAG. Intrarubral injection of LY379268 did not influence the protein expressions of TNF-α and IL-1β in normal rats, while intrarubral injection of EGLU rather than β-NAAG significantly boosted the expressions of TNF-α and IL-1β. These findings suggest that red nucleus mGluR2 but not mGluR3 mediates inhibitory effect in the development of SNI-induced neuropathological pain by suppressing the expressions of TNF-α and IL-1β. mGluR Ⅱ may be potential targets for drug development and clinical treatment of neuropathological pain. • Red nucleus (RN) mGluR2 but not mGluR3 is reduced in spared nerve injury rats. • RN mGluR2 but not mGluR3 activation inhibits the development of neuropathic pain. • RN mGluR2 inhibits neuropathic pain by suppressing the expression of TNF-α. • RN mGluR2 inhibits neuropathic pain by suppressing the expression of IL-1β. [ABSTRACT FROM AUTHOR]

Raising the configurational entropy in a solid solution ceramic is regarded as a promising strategy to improve the mechanical properties of ceramics, especially when five or more elements are mixed to form so‐called high‐entropy ceramics. However, in this study, we report that the binary (TiZr)C solid solution ceramics can demonstrate high hardness comparable or even superior to high‐entropy ceramics. Followed by a carbothermal reduction synthesis of carbide powders, the bulk ceramics were synthesized by hot pressing. Via increasing the hot pressing temperature to 2200°C, a full solid solution of equimolar (TiZr)C was obtained in contrast to phase separation at lower sintering temperatures, for example, 2000 and 2100°C. The dislocation networks are observed in the single‐phase (TiZr)C ceramic and should be the product of competition between enthalpy and entropy in a binary full solid solution. These defects finally contribute to the high nano‐hardness of 41.9 ± 1.4 GPa (H) and the Vickers hardness of 22.0 ± 0.6 GPa (HV at 49 N). [ABSTRACT FROM AUTHOR]

Background: Compound Turkish gall ointment (CTGO) has a long history of being widely used as a folk medicine in Xinjiang for the treatment of eczema. CTGO is currently in the pre-investigational new drug application stage, but its pharmacological mechanisms of action have not yet been clarified. Methods: First, a sensitive and reliable ultra-high performance liquid chromatography-Q exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry (UHPLC-Q-Orbitrap HRMS) technique was established. Second, an integrative strategy of network analysis and molecular docking based on identified and retrieved ingredients was implemented to investigate the potential targets and pathways involved in the treatment of eczema with CTGO. Finally, Sprague–Dawley (SD) rats with eczema were prepared to verify the predicted results. The skin conditions of the rats were observed, evaluated, and scored. Skin tissues were observed by hematoxylin–eosin (HE) staining, and the levels of serum interferon-γ (IFN-γ) and interleukin-4 (IL-4) were determined by enzyme-linked immunosorbent assay (ELISA). The expression levels of toll-like receptor 4 (TLR4), nuclear factor kappa-B p65 (NF-κB p65), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Results: A total of 29 compounds were identified. We found 38 active components and 58 targets for the treatment of eczema, which included 118 signaling pathways related to inflammation, immunity, and apoptosis. CTGO significantly improved the skin surface and histopathological characteristics of eczema-affected rats, downregulated the expression of IL-4, TLR4, NF-κB (p65), IL-1β, and TNF-α, and upregulated the expression level of IFN-γ. Conclusion: We predicted and validated our prediction that CTGO may be used to treat eczema by affecting the TLR4/NF-κB signaling pathway, which provides guidance for future experimental studies. [ABSTRACT FROM AUTHOR]

An unprecedented Zn(OTf)2-catalyzed asymmetric Michael addition/cyclization cascade of 3-nitro-2 H-chromenes with 3-isothiocyanato oxindoles has been disclosed. This transformation provides an efficient access to various synthetically important polycyclic spirooxindoles in a highly stereoselective manner under mild conditions (72-99 % yields, up to >95:5 d.r. and >99 % ee). The reaction leads to the formation of three consecutive stereocenters, including 1,3-nonadjacent tetrasubstituted carbon stereocenters, in a single operation. A bifunctional activation model of the chiral Zn(OTf)2/bis(oxazoline) complex was proposed based on control experiments, wherein the ZnII moiety serves as a Lewis acid and the N atom of the free NH group acts as a Lewis base by a hydrogen-bonding interaction. [ABSTRACT FROM AUTHOR]

Our previous study has identified that glutamate in the red nucleus (RN) facilitates the development of neuropathic pain through metabotropic glutamate receptors (mGluR). Here, we further explored the actions and possible molecular mechanisms of red nucleus mGluR Ⅰ (mGluR1 and mGluR5) in the development of neuropathic pain induced by spared nerve injury (SNI). Our data indicated that both mGluR1 and mGluR5 were constitutively expressed in the RN of normal rats. Two weeks after SNI, the expressions of mGluR1 and mGluR5 were significantly boosted in the RN contralateral to the nerve injury. Administration of mGluR1 antagonist LY367385 or mGluR5 antagonist MTEP to the RN contralateral to the nerve injury at 2 weeks post-SNI significantly ameliorated SNI-induced neuropathic pain. However, unilateral administration of mGluRⅠ agonist DHPG to the RN of normal rats provoked a significant mechanical allodynia, this effect could be blocked by LY367385 or MTEP. Further studies indicated that the expressions of TNF-α and IL-1β in the RN were also elevated at 2 weeks post-SNI. Administration of mGluR1 antagonist LY367385 or mGluR5 antagonist MTEP to the RN at 2 weeks post-SNI significantly inhibited the elevations of TNF-α and IL-1β. However, administration of mGluR Ⅰ agonist DHPG to the RN of normal rats significantly enhanced the expressions of TNF-α and IL-1β, these effects were blocked by LY367385 or MTEP. These results suggest that activation of red nucleus mGluR1 and mGluR5 facilitate the development of neuropathic pain by stimulating the expressions of TNF-α and IL-1β. mGluR Ⅰ maybe potential targets for drug development and clinical treatment of neuropathic pain. • Enhanced mGluR1and mGluR5 in the red nucleus (RN) of spared nerve injury rats. • Activation of RN mGluR1and mGluR5 facilitate the development of neuropathic pain. • RN mGluR1and mGluR5 facilitate neuropathic pain by stimulating TNF-α expression. • RN mGluR1and mGluR5 facilitate neuropathic pain by stimulating IL-1β expression. [ABSTRACT FROM AUTHOR]

A series of morpholiny analogues were efficiently obtained through nucleophilic aromatic substitution (S N Ar) under microwave irradiation with simple operation. Furthermore, the molecular docking studies suggested that the compound 4m could bind receptor PYR1 much more strongly than abscisic acid. Significantly, the application of 4m could reduce the permeability of cell membranes to enhance the tolerance. Furthermore, the growth of root and above-ground parts and the fresh weight was improved when treatment with 4m under cadmium stress at 200–500 mg/L. Thus, compound 4m was successfully designed and synthesized as the most potent candidate. [Display omitted] • Microwave-assisted approach to morpholine analogue. • R was mono-substitution, 13 Samples, 75–85 %; R = 3,5-diF, 40 %. • The 4m (R = 6-F) could bind the receptor much effectively than ABA. • Treatment with 4m could reduce cadmium stress. [ABSTRACT FROM AUTHOR]

Hybrid rice technology has been used for more than 50 years, and eating and cooking quality (ECQ) has been a major focus throughout this period. Waxy (Wx) and alkaline denaturation (ALK) genes have received attention owing to their pivotal roles in determining rice characteristics. However, despite significant effort, the ECQ of restorer lines (RLs) has changed very little. By contrast, obvious changes have been seen in inbred rice varieties (IRVs), and the ECQ of IRVs is influenced by Wx, which reduces the proportion of Wxa and increases the proportion of Wxb, leading to a decrease in amylose content (AC) and an increase in ECQ. Meanwhile, ALK is not selected in the same way. We investigated Wx alleles and AC values of sterile lines of female parents with the main mating combinations in widely used areas. The results show that almost all sterile lines were Wxa-type with a high AC, which may explain the low ECQ of hybrid rice. Analysis of hybrid rice varieties and RLs in the last 5 years revealed serious homogenisation among hybrid rice varieties. [ABSTRACT FROM AUTHOR]

A visible light-induced, aerobic oxyamidation reaction of indoles, using air as the sole oxidant, has been developed. This process serves as a photocatalytic strategy to generate efficiently tetrahydro-5 H-indolo[2,3- b]quinolinols, which may have interesting biological and pharmacological activities owing to their privileged indoline structure. [ABSTRACT FROM AUTHOR]