Amphiphilic Polyurethane with Cluster-Induced Emission for Multichannel Bioimaging in Living Cell Systems.

The development of single-component materials with low cytotoxicity and multichannel fluorescence imaging capability is a research hotspot. In the present work, highly electron-deficient pyrazine monomers were covalently connected into a polyurethane backbone using addition polymerization with terminal poly(ethylene glycol) monomethyl ether units containing a high density of electron pairs. Thereby, an amphiphilic polyurethane-pyrazine (PUP) derivative has been synthesized. The polymer displays cluster-induced emission through compact inter- and/or intramolecular noncovalent interactions and extensive through-space electron coupling and delocalization. Molecular rigidity facilitates red-shifted emission. Based on hydrophilic/hydrophobic interactions and excitation dependence emission at low concentrations, PUP has been self-assembled into fluorescent nanoparticles (PUP NPs) without additional surfactant. PUP NPs have been used for cellular multicolor imaging to provide a variety of switchable colors on demand. This work provides a simple molecular design for environmentally sustainable, luminescent materials with excellent photophysical properties, biocompatibility, low cytotoxicity, and color modulation.

Protective mechanisms of quercetin in neonatal rat brain injury induced by hypoxic-ischemic brain damage (HIBD).

Neonatal hypoxic-ischemic brain damage (HIBD) is a leading cause of infant mortality worldwide. This study explored whether quercetin (Que) exerts neuroprotective effects in a rat model of HIBD. A total of 36 seven-day-old Sprague-Dawley rats were divided into control, Que, HI, and HI + Que groups. The Rice method was used to establish HIBD in HI and HI + Que rats, which were treated with hypoxia (oxygen concentration of 8%) for 2 h after ligation of the left common carotid artery. The rats in the HI + Que group were intraperitoneally injected with Que (30 mg/kg) 1 h before hypoxia, and the rats in the Que group were only injected with the same amount of Que. Brain tissues were harvested 24 h postoperation and assessed by hematoxylin and eosin staining, 2,3,5-triphenyltetrazolium chloride staining, and terminal deoxynucleotidyl transferase dUTP nick-end labeling assay; relative gene and protein levels were evaluated by RT-qPCR, IHC, or western blot (WB) assay. Brain tissue morphologies were characterized by transmission electron microscopy (TEM); LC3B protein levels were assessed by immunofluorescence staining. Escape latencies and platform crossing times were significantly improved (p < .05) in HI + Que groups; infarct volume significantly decreased (p < .001), whereas the numbers of autophagic bodies and apoptotic cells increased and decreased, respectively. Meanwhile, NLRX1, ATG7, and Beclin1 expressions were significantly upregulated, and mTOR and TIM23 expressions, LC3B protein level, and LC 3II/LC 3I ratio were significantly downregulated. Que exerted neuroprotective effects in a rat model of HIBD by regulating NLRX1 and autophagy.

Co-based MOF heterogeneous catalyst for the efficient degradation of organic dye via peroxymonosulfate activation.

In this study, a new cobalt-based metal-organic framework (JLNU-500), [Co2(OH)(PBA)(AIP)]·3DMA·0.75H2O (4-(pyridin-4-yl) benzoic acid (HPBA), 5-aminoisophthalic acid (H2AIP) and N,N-dimethylacetamide (DMA)), was fabricated using a solvothermal method. JLNU-500 has 3D network architecture with 1D nanopore channels. The prepared JLNU-500 can activate peroxymonosulfate (PMS) for Rhodamine B (RhB) dye decolorization. Interestingly, catalyst JLNU-500 exhibited high efficiency for PMS activation, and nearly 100% (above 99.8%) removal of RhB with a high concentration (50.0 mg L-1, 100 mL) was achieved within 6 min. The reaction rate constant of the JLNU-500/PMS system was 1.02 min-1 calculated based on the pseudo-first-order kinetics, which is higher than that of the other reported catalysts. Furthermore, the factors, which could influence PMS activation were also investigated, such as PMS dosage, catalyst dosage, pollutant RhB concentration, reaction temperature and solution pH. More importantly, the radical trapping experiments ferreted out that sulfate (SO4˙-) and hydroxyl (˙OH) radicals were the dominating oxidants in the removal of RhB. Moreover, the possible degradation mechanism was elucidated. This study provides new prospects for fabricating new MOFs that can potentially be employed for high-efficiency catalytic oxidation as heterogeneous catalysts.

Multicolor Luminescence of a Polyurethane Derivative Driven by Heat/Light-Induced Aggregation.

The study of aggregate formation and its controllable effect on luminescence behavior has a far-reaching influence in establishing a universal aggregation photophysical mechanism. In this paper, we obtained clusters with different extents of aggregation by heat-induced or light-triggered aggregation of a new polyurethane derivative (PUE). The controllable regulation of multicolor fluorescence of a single (nondoped) polymeric material is realized. The luminescence behavior of PUE varies with microscopic control of the aggregation structure. Compared with the powder state, the enhanced atom-atom and group-group interactions of PUE-gel effectively limit the nonradiative transitions in the excited state and result in a red-shift in emission. This work avoids complex organic synthesis and demonstrates a simple strategy to induce aggregation and regulate the emitting color of macromolecules, providing a template for developing new materials for multicolor fluorescence. In addition, a pattern was constructed with encryption, anticounterfeiting, and information transmission functions which provide a proof-of-concept demonstration of the practical potential of PUE as a smart material.

A novel zirconium-based metal-organic framework covalently modified by methyl pyridinium bromide for mild and co-catalyst free conversion of CO2 to cyclic carbonates.

Building metal-organic frameworks (MOFs) covalently modified by onium halides is a promising approach to develop efficient MOF-based heterogeneous catalysts for the cycloaddition of CO2 to epoxides (CCE) into cyclic carbonates. Herein, we report a novel zirconium-based MOF covalently modified by methyl pyridinium bromide, Zr6O4(OH)4(MPTDC)2.2(N-CH3-MPTDC)3.8Br3.8 ((Br-)CH3-Pyridinium-MOF-1), where MPTDC denotes 3-methyl-4-pyridin-4-yl-thieno[2,3-b] thiophene-2,5-dicarboxylate. The structure and composition of this complex were fully characterized with PXRD, NMR, XPS, TEM and so on. CO2 adsorption experiments show that (Br-)CH3-Pyridinium-MOF-1 has a higher affinity for CO2 than its electrically neutral precursor, which should be attributed to the fact that charging frameworks containing pyridinium salt have stronger polarization to CO2. (Br-)CH3-Pyridinium-MOF-1 integrated reactive Lewis acid sites and Br- nucleophilic anions and exhibited efficient catalytic activity for CCE under ambient pressure in the absence of co-catalysts and solvents. Furthermore, (Br-)CH3-Pyridinium-MOF-1 was recycled after five successive cycles without substantial loss in catalytic activity. The corresponding reaction mechanism also was speculated.

Genome-wide investigation and expression analysis of the AP2/ERF family for selection of agarwood-related genes in Aquilaria sinensis (Lour.) Gilg.

Aquilaria sinensis is an important non-timber tree species for producing high-value agarwood, which is widely used as a traditional medicine and incense. Agarwood is the product of Aquilaria trees in response to injury and fungal infection. The APETALA2/ethylene responsive factor (AP2/ERF) transcription factors (TFs) play important roles in plant stress responses and metabolite biosynthesis. In this study, 119 AsAP2/ERF genes were identified from the A. sinensis genome and divided into ERF, AP2, RAV, and Soloist subfamilies. Their conserved motif, gene structure, chromosomal localization, and subcellular localization were characterized. A stress/defense-related ERF-associated amphiphilic repression (EAR) motif and an EDLL motif were identified. Moreover, 11 genes that were highly expressed in the agarwood layer in response to whole-tree agarwood induction technique (Agar-Wit) treatment were chosen, and their expression levels in response to methyl jasmonate (MeJA), salicylic acid (SA), or salt treatment were further analyzed using the quantitative real time PCR (qRT-PCR). Among the 11 genes, eight belonged to subgroup B-3. All 11 genes were significantly upregulated under salt treatment, while eight genes were significantly induced by both MeJA and SA. In addition, the gene clusters containing these upregulated genes on chromosomes were observed. The results obtained from this research not only provide useful information for understanding the functions of AP2/ERF genes in A. sinensis but also identify candidate genes and gene clusters to dissect their regulatory roles in agarwood formation for future research.

Genome-wide analysis of basic helix-loop-helix (bHLH) transcription factors in Aquilaria sinensis.

The basic helix-loop-helix (bHLH) transcription factors are involved in several biological processes both in plant development and stress responses. Agarwood, a major active and economical product, is only induced and accumulated when the roots, stems, or branches are wounded in Aquilaria sinensis. Although genome-wide comprehensive analyses of the bHLH family have been identified in many plants, no systematic study of the genes in this family has been conducted in A. sinensis. In this study, 105 bHLH genes were identified in A. sinensis through genome-wide analysis and named according to their chromosomal locations. Based on a phylogenetic tree, AsbHLH family proteins were classified into 18 subfamilies. Most of them were distributed on eight chromosomes, with the exception of two genes. Based on the tissue-specific expression characteristics and expression patterns in response to methyl jasmonate (MeJA) treatment, seven AsbHLH genes were likely involved in wound-induced agarwood formation. The results provide comprehensive information on AsbHLHs that can be used to elucidate the molecular functions and physiological roles of these proteins in A. sinensis.

1,3-Benzodioxole-based fibrate derivatives as potential hypolipidemic and hepatoprotective agents.

A series of target compounds 1,3-benzodioxole-based fibrate derivatives were designed and synthesized. All the target compounds were preliminarily evaluated by hyperlipidemia mice induced by Triton WR-1339, in which compound 12 displayed a greater anti-hyperlipidemia activity than other compounds as well as positive drug fenofibrate (FF). 12 showed a significant reduction of plasma lipids, such as triglycerides (TG), total cholesterol (TC) and low-density lipoprotein cholesterin (LDL-C), in high fat diet (HFD) induced hyperlipidemic mice. In addition, hepatic transaminases (AST and ALT) were ameliorated after administration of 12, in particular the AST, and the histopathological examination showed that 12 improved the hepatic lipid accumulation. The expression of PPAR-α involved in lipids metabolism was up-regulated in the liver tissues of 12-treated group. Other significant activity such as antioxidant, and anti-inflammation was confirmed and reinforced the effects of 12 as a potential hypolipidemia and hepatoprotective agent.

Targeted MR Imaging Adopting T1-Weighted Ultra-Small Iron Oxide Nanoparticles for Early Hepatocellular Carcinoma: An in vitro and in vivo Study.

Objective The purpose of this study was to produce an arginylglycylaspartic acid (RGD) peptide-modified ultra-small superparamagnetic iron oxide (Fe3O4) nanoparticles (NPs) for targeted magnetic resonance (MR) imaging of hepatocellular carcinoma (HCC) cells and verify its utility as a T1 positive MRI imaging contrast agent in vitroand in vivo.Methods The carboxylated Fe3O4 NPs stabilized with sodium citrate were conjugated with polyethylene glycol (PEG)-linked RGD nanoparticles to form a novel target contrast agent Fe3O4-PEG-RGD NPs. The specificity of Fe3O4-PEG-RGD to bind RGD receptor was investigated in vitro by HepG2 cellular uptake and cell MR imaging, and in vivo by MR imaging of subcutaneous HepG2 tumors of nude mice.Results The formed Fe3O4-PEG-RGD NPs displayed good biocompatibility, and the ultrahigh r1 relaxivity was 1.37 mM -1S -1. The synthesized Fe3O4-PEG-RGD NPs were demonstrated spherical-like with an approximate diameter of 2.7 nm in similar size. The targeting effect to HepG2 cells was confirmed by in vitro cellular uptake and cell MR imaging. The in vivo MR imaging of nude mice demonstrated that the MR signal intensity enhancement of HepG2 tumor in Fe3O4-PEG-RGD NPs treated mice was significantly higher than in mice treated with non-targeted Fe3O4-mPEG NPs at the same post-administration time point. Conclusion The results indicate that the Fe3O4-PEG-RGD particles have potential utility as T1 positive contrast agent in targeted MR imaging.

[Estimating the climatic capacity of food security in Henan Province, China under the future climate change scenarios]. / æœªæ¥æ°”å€™å˜åŒ–æƒ æ™¯ä¸‹æ²³å—çœç²®é£Ÿå®‰å ¨æ°”å€™æ‰¿è½½åŠ›è¯„ä¼°.

To explore the effects of future climate change on food production in Henan Province, the climate potential productivity and its change characteristics in Henan Province were calculated by agro-ecological zone (AEZ) model. This study was based on the production potential and climate resource carrying capacity of summer maize and winter wheat, combined with the observation data of 111 meteorological stations in Henan Province from 1961 to 2017 and the meteorological data under two emission scenarios of RCP4.5 and RCP8.5 in 2041-2080. With the grain demand index under different living standards, we analyzed climate carrying capacity and surplus space of Henan Pro-vince. The results showed that the average climatic potential productivity of maize was 18408.87 kg·hm-2 from 1961 to 2017, with high values in the middle and east, and low values in the west. Compared with the reference period (1981-2010), climatic potential productivity of maize under RCP4.5 and RCP8.5 decreased by 13.0% and 8.0% respectively, with the high value center shifting from the east to the southwest of Henan. The average climatic potential productivity of wheat was 10889.79 kg·hm-2, which was high in the middle region and low in the north. Compared with the reference period, climatic potential productivity of wheat under RCP4.5 and RCP8.5 decreased by 18.6% and 21.7%, respectively. Under the current condition of subsistence and well-off food demand, the maximum carrying capacity of climate resources respectively could support 252 million and 183 million people. In 2070s (2071-2080), the average supporting population of the maximum climate resource carrying capacity (Cmax) would decrease. Compared with the reference period, Cmax under the level of well-off and subsistence would decrease by 9.7% and 18.4% respectively in RCP4.5 scenario, and 7.7% and 16.6% respectively in RCP8.5 scenario. Under current climate condition, the relative surplus rate of climate resources in Henan Province ranged from -93.0% to 356.9%. Compared with the reference period, the relative residual rate of climate resources in the future would reduce nearly 40%.

Genome-wide analysis of WRKY transcription factors in Aquilaria sinensis (Lour.) Gilg.

The WRKY proteins are a superfamily of transcription factor that regulate diverse developmental and physiological processes in plants. Completion of the whole-genome sequencing of Aquilaria sinensis allowed us to perform a genome-wide investigation for WRKY proteins. Here, we predicted 70 WRKY genes from the A. sinensis genome and undertaken a comprehensive bioinformatic analysis. Due to their diverse structural features, the 70 AsWRKY genes are classified into three main groups (group I-III), with five subgroups (IIa-IIe) in group II, except two belong to none of them. Distinct expression profiles of AsWRKYs with RNA sequencing data revealed their diverse expression patterns among different tissues and in the process of whole-tree-inducing agarwood formation. Based on the expression characteristics, we predict some AsWRKYs are pseudogenes, and some may be involved in the biosynthesis of agarwood sesquiterpenes as activators or repressors. Among the tested genes treated with MeJA and H2O2, most of them are induced by H2O2, but downregulated by MeJA, implying the complexity of their involvement in signal transduction regulation. Our results not only provide a basic platform for functional identification of WRKYs in A. sinensis but important clues for further analysis their regulation role in agarwood formation.

WRKY44 represses expression of the wound-induced sesquiterpene biosynthetic gene ASS1 in Aquilaria sinensis.

Agarwood is derived from wounds in Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury; However, the molecular mechanisms by which wounding leads to sesquiterpene formation remain largely unknown. Agarwood sesquiterpene synthase 1 (ASS1) is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a crucial jasmonate (JA)-responsive wound-inducible synthase. However, it is not known why ASS1 is not expressed in healthy trees and how its expression is induced as a result of wounding. Here, we report that ASS1 is a wound-induced gene with a promoter in which a 242-bp region (-973 to -731bp) is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Down-regulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. In addition, AsWRKY44 is degraded and the expression of ASS1 is significantly up-regulated in response to exogenous application of methyl jasmonate. Thus, AsWRKY44 is a crucial negative regulator of wound-induced ASS1 transcription, and is central to the mechanism of sesquiterpene biosynthesis in agarwood.

The complete mitochondrial genome sequence of Yarkand hare (Lepus yarkandensis).

We first reported the mitochondrial genome of Lepus yarkandensis. The mitogenome of L. yarkandensis contains 17,011 base pairs. The overall base composition of complete mitogenome is 28.13% A, 27.67% T, 22.02% C, and 22.17% G, with 44.20% of the GC content. All genes exhibit the typical mitochondrial gene arrangement and transcribing directions. Phylogenetic analysis of 9 Lepus species was performed based on the sequence of cytochrome b gene using the Maximum Likelihood method in MEGA 7.0. The results suggested that L. yarkandensis is closely related to Lepus timidus. The results are helpful to future studies on molecular evolution, population genetics, and wildlife protection of L. yarkandensis.

5-(4-Hydroxyphenyl)-3H-1,2-dithiole-3-thione-based fibrates as potential hypolipidemic and hepatoprotective agents.

Hypolipidemic effects of the newly synthesized 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione-based fibrates were evaluated in Triton WR-1339 and high-fat diet (HFD)-induced hyperlipidemic mice. Preliminary screening of all the synthesized compounds was done by using an acute model (Triton WR-1339 model), in which compound 6 shown more significant antidyslipidemic activity than fenofibrate (FF). The compound 6 was also found to reduce serum triglyceride (TG), total cholesterol (TC) and low density lipoprotein cholesterin (LDL) in HFD-induced hyperlipidemic mice. Moreover, compound 6 displayed hepatoprotective effect, a significant amelioration in hepatic indices (AST and ALT) toxicity was observed and the histological examination showed that compound 6 inhibited the development of hepatic lipid accumulation and ameliorated the damage in hepatic tissue compared to model mice. Additional effects such as the potent antioxidant and anti-inflammatory action confirmed and reinforced the efficacy of compound 6 as a new agent of dual-effect hypolipidemic and hepatoprotective activities.

A new multifunctional hydroxytyrosol-clofibrate with hypolipidemic, antioxidant, and hepatoprotective effects.

Oxidative stress has been regarded as the leading mechanism of the hepatotoxicity of clofibrate (CF). To achieve multifunctional novel hypolipidemic agents with hypolipidemia, antioxidant, and ameliorating liver injury, clofibric acid derivative hydroxytyrosol-clofibrate (CF-HT) was synthesized by molecular hybridization. CF-HT exhibited significant hypolipidemia, reducing serum triglyceride (TG), total cholesterol (TC), and malonaldehyde (MDA) by 30%, 33%, and 29% in hyperlipidemic mice induced by Triton WR 1339. CF-HT also shown hepatoprotective effect, a significant decrease in hepatic indices toxicity was observed, i.e. aspartate and lactate transaminases (AST and ALT) activities, alkalines phosphatases (ALP), and total bilirubin (TBIL) levels. The liver weight and liver coefficient were also ameliorated. Serum superoxide dismutase (SOD) was significantly elevated, and serum catalase (CAT) and malondialdehyde (MDA) content were remarkably restored. The hepatic glutathione (GSH) content was obviously increased and hepatic oxidized glutathione (GSSG) content was reduced dramatically by CF-HT, as compared to the CF treated mice (p < 0.05). Moreover, the histopathological damage that hepatocyte hyperplasia and hypertrophy was also significantly ameliorated by treatment with CF-HT. Therefore, the results indicated that CF-HT exerted more potent hypolipidemic activity and definite hepatoprotective effect which may mainly be associated with its antioxidative property in mice.

Hydroxytyrosol nicotinate, a new multifunctional hypolipidemic and hypoglycemic agent.

Hydroxytyrosol (HT) is a natural polyphenol antioxidant that exists in olive oil. In the study of multifunctional hypolipidemic of nicotinic derivatives, we found that hydroxytyrosol nicotinate (HT-N) incorporation of niacin with HT displayed ?-glucosidase inhibitory activities in vitro, such as yeast ?-glucosidase (IC50?=?117.72??M) and rat intestinal ?-glucosidases maltase (IC50?=?31.86??M) and sucrase (IC50?=?22.99??M), and had a good control of postprandial blood glucose (PBG). HT-N shown significantly hypoglycemic action by 16.9% and protection of pancreatic tissue in type 2 diabetic mellitus (T2DM) mouse model. HT-N also shown a potent antioxidant activity and property of anti-glycation in vitro, which were benefit for ameliorating diabetic complications. Moreover, HT-N exhibited much significant hypolipidemia, lowering plasma triglyceride (TG), total cholesterol (TC), and malonaldehyde (MDA) by 34.6%, 45.8% and 32.1% respectively, in hyperlipidemic mice induced by Triton WR 1339. The results indicated that HT-N has hypolipidemic, hypoglycemic and antioxidant actions. All these properties could be conducive to amelioration of oxidative stress, hyperlipidemia, and diabetes that HT-N may serve as a multifunctional potential therapeutic strategy in diabetic patients with hyperlipidemia.

A multifunctional microporous metal-organic framework: efficient adsorption of iodine and column-chromatographic dye separation.

In this work, a multifunctional microporous metal-organic framework (MOF), [Cd(ABTC)(H2O)2(DMA)]·4DMA (JLNU-4; JLNU = Jilin Normal University; H4ABTC = 3,3',5,5'-azobenzenetetracarboxylic acid), has been synthesized based on the ligand H4ABTC under solvothermal conditions. JLNU-4 shows excellent uptake of iodine both in solution and in the vapor phase, owing to the existence of a microporous structure in JLNU-4. The adsorption kinetics during the process of iodine adsorption were analyzed via a series of qualitative and quantitative analyses, such as the Langmuir and Freündlich adsorption isotherms. In addition, according to UV/vis spectroscopy analysis and the colour variance of JLNU-4, the relatively small sized dye methylene blue (MB) could be efficiently adsorbed by JLNU-4, through size-exclusion effects. Particularly, JLNU-4 can serve as a column-chromatographic filler for the separation of dye molecules. Therefore, JLNU-4 is a multifunctional microporous MOF for iodine adsorption and column-chromatographic dye separation.

Transcription Factor AsMYC2 Controls the Jasmonate-Responsive Expression of ASS1 Regulating Sesquiterpene Biosynthesis in Aquilaria sinensis (Lour.) Gilg.

Sesquiterpenes are one of the most important defensive secondary metabolite components of agarwood. Agarwood, which is a product of the Aquilaria sinensis response to external damage, is a fragrant and resinous wood that is widely used in traditional medicines, incense and perfume. We previously reported that jasmonic acid (JA) plays an important role in promoting agarwood sesquiterpene biosynthesis and induces expression of the sesquiterpene synthase ASS1, which is a key enzyme that is responsible for the biosynthesis of agarwood sesquiterpenes in A. sinensis. However, little is known about this molecular regulation mechanism. Here, we characterized a basic helix-loop-helix transcription factor, AsMYC2, from A. sinensis as an activator of ASS1 expression. AsMYC2 is an immediate-early jasmonate-responsive gene and is co-induced with ASS1. Using a combination of yeast one-hybrid assays and chromatin immunoprecipitation analyses, we showed that AsMYC2 bound the promoter of ASS1 containing a G-box motif. AsMYC2 activated expression of ASS1 in tobacco epidermis cells and up-regulated expression of sesquiterpene synthase genes (TPS21 and TPS11) in Arabidopsis, which was also promoted by methyl jasmonate. Our results suggest that AsMYC2 participates in the regulation of agarwood sesquiterpene biosynthesis in A. sinensis by controlling the expression of ASS1 through the JA signaling pathway.

Conjugated microporous polymer networks with adjustable microstructures for high CO2 uptake capacity and selectivity.

A series of phenylene-based conjugated microporous polymers (CMPs) of the A6 + Mx (x = 2, 3, 4, 6) type were synthesized. By tuning the monomer length and geometry, the BET surface area of CMPs can be tuned from 571 to 1115 m2 g-1. Amongst the synthesized CMPs, A6CMP-1 exhibits the highest CO2 adsorption capacity of 1218 mg g-1 at 318 K and 60 bar pressure. In addition, A6CMP-4 shows a high selectivity ratio of 47 for CO2/N2.