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In plants, submergence from flooding causes hypoxia, which impairs energy production and affects plant growth, productivity, and survival. In Arabidopsis, hypoxia induces nuclear localization of the group VII ethylene-responsive transcription factor RELATED TO AP2.12 (RAP2.12), following its dissociation from the plasma membrane-anchored ACYL-COA BINDING PROTEIN1 (ACBP1) and ACBP2. Here, we show that polyunsaturated linolenoyl-CoA (18:3-CoA) regulates RAP2.12 release from the plasma membrane. Submergence caused a significant increase in 18:3-CoA, but a significant decrease in 18:0-, 18:1-, and 18:2-CoA. Application of 18:3-CoA promoted nuclear accumulation of the green fluorescent protein (GFP) fusions RAP2.12-GFP, HYPOXIA-RESPONSIVE ERF1-GFP, and RAP2.3-GFP, and enhanced transcript levels of hypoxia-responsive genes. Plants with decreased ACBP1 and ACBP2 (acbp1 ACBP2-RNAi, produced by ACBP2 RNA interference in the acbp1 mutant) had reduced tolerance to hypoxia and impaired 18:3-CoA-induced expression of hypoxia-related genes. In knockout mutants and overexpression lines of LONG-CHAIN ACYL-COA SYNTHASE2 (LACS2) and FATTY ACID DESATURASE 3 (FAD3), the acyl-CoA pool size and 18:3-CoA levels were closely related to ERF-VII-mediated signaling and hypoxia tolerance. These findings demonstrate that polyunsaturation of long-chain acyl-CoAs functions as important mechanism in the regulation of plant hypoxia signaling, by modulating ACBP-ERF-VII dynamics.

Summary The ability of the plant pathogen Xanthomonas campestris pv. campestris (Xcc) to cause disease is dependent on its ability to adapt quickly to the host environment during infection. Like most bacterial pathogens, Xcc has evolved complex regulatory networks that ensure expression and regulation of their virulence genes. Here, we describe the identification and characterization of a Fis‐like protein (named Flp), which plays an important role in virulence and type III secretion system (T3SS) gene expression in Xcc. Deletion of flp caused reduced virulence and hypersensitive response (HR) induction of Xcc and alterations in stress tolerance. Global transcriptome analyses revealed the Flp had a broad regulatory role and that most T3SS HR and pathogenicity (hrp) genes were down‐regulated in the flp mutant. β‐glucuronidase activity assays implied that Flp regulates the expression of hrp genes via controlling the expression of hrpX. More assays confirmed that Flp binds to the promoter of hrpX and affected the transcription of hrpX directly. Interestingly, the constitutive expression of hrpX in the flp mutant restored the HR phenotype but not full virulence. Taken together, the findings describe the unrecognized regulatory role of Flp protein that controls hrp gene expression and pathogenesis in Xcc.

In clinical applications, osseointegration is essential for the long-term stability of dental implants. Inspired by the hierarchical structure of natural bone, we applied the electrochemical etching (EC) technique to form a micro-nano structure on a titanium alloy (Ti6Al4V) substrate, called EC surface. Sand blasting and acid etching (SLA) and machined (M) methods were employed to generate micro and smooth textures, respectively, as the control groups. The surface topographies of the three substrates were characterized using scanning electron microscopy (SEM). Then, human osteoblast-like cells (MG63) were cultured on substrates, and adhesion, proliferation, morphology, alkaline phosphatase activity (ALP), and gene expression levels of Runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), osteopontin (OPN), and type I collagen (COLIA 1) were analyzed. MG63 cells cultured on the EC Ti alloy substrates displayed better cell adhesion, significant proliferation, and a higher production level of ALP, gene expressions of RUNX2, OCN, OPN and COLIA 1 (p < 0.01 or p < 0.05) compared with those of SLA and M substrates. These results indicate that the micro-nano structure fabricated by electrochemical etching method is beneficial for the biological functions of MG63 cells and may be a promising candidate in dental implants. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 757-769, 2017.

A new symmetric 16-membered macrodiolide, trichobotryside A (1), and two new asymmetric 18-membered macrodiolides trichobotrysides B–C (2–3) were obtained from the deep-sea-derived fungus Trichobotrys effuse DFFSCS021. Their structures were elucidated by extensive spectroscopic analysis. The absolute configurations of 1 and 2 were established by the methanolysis and modified Mosher method. And the methanolysis of both 1 and 2 produced the new compound of 4R,7S,9S-trihydroxyl-2-en-1-methyl decanoate (4). It was rare to obtain an 18-membered macrodiolide from nature. Compound 1 showed strong antifouling activity against Bugula neritina and Balanus amphitrite larvae settlement.

Trichobotrysins A–F (1–6), a class of new tetramic acid derivatives with a decalin ring, were characterized from the culture of Trichobotrys effuse DFFSCS021 derived from the deep sea sediment collected from the South China Sea. Their structures were elucidated by extensive spectroscopic analysis. Compounds 1, 2, and 4 exhibited significant selective cytotoxicity against human carcinoma KG-1a cell line with IC50 values of 5.44, 8.97, and 6.16 μM, and obvious antiviral activity towards HSV-1 with IC50 values of 3.08, 9.37, and 3.12 μM, respectively. This is the first time to report the anti-HSV-1 activity of this type of compounds.

Midday depressions in stomatal conductance (gs) and pho- tosynthesis are common in plants.The aim of this study was to understand the hydraulic determinants of midday gs, the coordination between leaf and stem hydraulics and whether regulation of midday gs differed between deciduous and evergreen broadleaf tree species in a subtropical cloud forest of Southwest (SW) China. We investigated leaf and stem hydraulics, midday leaf and stem water potentials, as well as midday gs of co-occurring deciduous and ever- green tree species. Midday gs was correlated positively with midday stem water potential across both groups of species, but not with midday leaf water potential. Species with higher stem hydraulic conductivity and greater daily reliance on stem hydraulic capacitance were able to main- tain higher stem water potential and higher gs at midday. Deciduous species exhibited significantly higher stem hydraulic conductivity, greater reliance on stem capaci- tance, higher stem water potential and gs at midday than evergreen species. Our results suggest that midday gs is more associated with midday stem than with leaf water status, and that the functional significance of stomatal regulation in these broadleaf tree species is probably for preventing stem xylem dysfunction.

An aggregate signature scheme is a digital signature scheme that allows aggregation of n distinct signatures by n distinct users on n distinct messages. In this paper, we present an aggregate signcryption scheme (ASC) that is useful for reducing the size of certification chains (by aggregating all signatures in the chain) and for reducing message size in secure routing protocols. The new ASC scheme combines identity-based encryption and the aggregation of signatures in a practical way that can simultaneously satisfy the security requirements for confidentiality and authentication. We formally prove the security of the new scheme in a random oracle model with respect to security properties IND-CCA2, AUTH-CMA2, and EUF-CMA.

Objective Angiographic slow/no-reflow during emergency percutaneous coronary intervention (PCI) in patients with ST-elevated acute myocardial infarction (AMI) may result in unfavorable outcomes. The aim of our study was to investigate the clinical factors and angiographic findings that predict slow/no-reflow phenomenon and the long-term prognosis of AMI patients with angiographic slow/no-reflow. Methods A total of 210 consecutive AMI patients, who underwent primary PCI within 12 hours of symptom onset were divided into a normal flow group (thrombolysis in myocardial infarction [TIMI] flow grade 3, n = 169) and a slow/no-reflow group (≤TIMI flow grade 2, n = 41), based on cineangiograms performed during PCI. Results A total of 41 patients (19.5%) developed slow/no-reflow phenomenon. Univariate analysis showed that delayed reperfusion, high thrombus burden on baseline angiography, and acute hyperglycemia all correlated with slow/no-reflow (P < 0.05 for all). Multivariate analysis revealed that hyperglycemia on admission (≥10 mmol/L; odds ratio [OR]: 1.7, 95% confidence interval [CI]: 1.423–2.971, P = 0.012), reperfusion time (≥6 h; OR:1.4, 95% CI: 1.193–1.695, P = 0.040), and high thrombus burden (OR: 1.6, 95% CI: 1.026–2.825, P = 0.031) were significant and independent predictors of angiographic slow/no-reflow. The 6-month mortality and incidence of major adverse cardiac and cerebrovascular events (MACCE) were significantly higher in the slow/no-reflow group than in the normal flow group. Angiographic slow/no-reflow was independently predictive of MACCE (hazard ratio [HR]: 2.642, 95% CI: 1.304–5.932, P = 0.028). Conclusion Delayed reperfusion, high thrombus burden on baseline angiography, and blood glucose level on admission can be used to stratify AMI patients into a lower or higher risk for angiographic slow/no-reflow during PCI. In addition, angiographic slow/no-reflow predicts an adverse outcome in AMI patients. Copyright © 2010 Wiley Periodicals, Inc.

The reaction between K(1-C5H9C9H6) and anhydrous LnCl3 (Ln=Sm, Yb) in the molar ratio of 2:1 in THF with subsequent treatment by Na-K alloy afforded (1-C5H9C9H6)2Ln-(THF)n(Ln=Sm, n=1; Ln=Yb, n=2), while the reaction of Sml2 with K(1-C5H9C9H6) in the molar ratio of 1:2 in THF gave the anionic complex K(1-C5H9C9H6)3Sm(THF)3. The X-ray structure of (1-C5H9C9H6)2Yb(THF)2 showed that central metal Yb is coordinated by two cyclopentadienyl rings of 1-cyclopentylindenyls and two oxygen atoms from two tetrahydrofuran molecules to form pseudo-tetrahedral coordinate geometry. All these complexes are active for the polymerization of acrylonitrile.

Two new polyoxygenated steroids, (1 alpha,3 beta,7 alpha,11 alpha,12 beta)-gorgost-5-ene-1,3,7,11,12-pentol 12-acetate (1) and 11-O-acetyl-22-epihippuristanol (2), and a new alkaloid. 2,3,5,6,11,11b-hexahydro-2-hydroxy-1H-indolizine[8,7-b]indole-2-carboxylic acid (3), together with three known compounds. 22-epihippuristanol (4), hippuristanol (5), and tryptamine (6), were isolated from the EtOH/CH2Cl2 extracts of the South China Sea gorgonian Isis minorbruchyblasta. The structures of the new compounds were determined by spectroscopic methods. Compound 1 showed weak cytotoxicity against A549, HONE1. and He La cancer cell lines and strong anti larval activity towards Bugula neritina larvae with an EC50 value of 5.8 mu g/ml. Compound 5 showed moderate cytotoxicity against A549. HONE1, and He La cell lines, and the epimer mixture 4/5 (weight ratio 3 :2) exhibited potent cytotoxicity against A549 and HONE1 cell lines with IC50 values of 4.2 and 4.8 mu g/ml, which indicated that epimers 4 and 5 might have a synergistic effect on their cytotoxicity against A549 and HONE1 cell lines.

Four new coumarins, micromelosides A-D, together with four known coumarins were isolated from the stem bark of Micromelum fatcatum. The complete assignments of the H-1 and C-13 NMR chemical shifts for these new compounds were achieved by means of 1D and 2D NMR techniques, including H-1-H-1 COSY, HSQC, HMBC and NOE difference. Copyright (C) 2009 John Wiley & Sons, Ltd.

Two new iridoid glycosides, named scyphiphorins A (1) and B (2), together with four known compounds. geniposidic acid (= (1S, 4aS, 7aS)-1-(beta-D-glucopyranosyloxy)- 1,4a,5,7a-tetrahydro-7-(hydroxylmethyl)cyclopenta[c]pyr an-4-carboxylic acid; 3), 4-(4-hydroxy-3-methoxybenzyl)butan-2-one, oleanolic acid (=(3 beta)-3-hydroxyolean-12-en-28-oic acid). and stigmasterol beta-D-glucoside ( =(3 beta,22E)-stigmasta-5.22-dien-3-yl beta-D-glucopyranoside), were isolated for the first time from the stem bark of a Chinese mangrove. Scyphiphora hydrophyllacea GAERTN. f.. The structures of compounds I and 2 were determined as 10-O-benzoylgeniposidic acid and 10-O-[(2E, 6R)-8-hydroxy-2,6-dimethyl-1-oxooct-2-en-1-yl]geniposidic acid. respectively. on the basis of spectroscopic data and chemical methods, including 2D NMR techniques.

An efficient and scalable N-allylic alkylation of variously substituted indole derivatives and other N-heterocycles using diaryl and aryl alkyl propenylacetates is described which generally proceeds with high yields and enantioselectivities.

isolation, structure determination and biological activity of nine new oxindole alkaloids, cyclopiamides B—J (I)—(V)

Five new cyclopentane-condensed chromones, coniochaetones G-K (I) - (III), are isolated together with four known compounds from the crude extract of marine-derived fungus Penicillium oxalicum.

Two new polyoxygenated steroids, reticulatic acid (1) and reticulatin (2), together with a known compound 3,22,25-trihydroxy-16-24,20-24-bisepoxy-3 beta,16 beta,20S,22R,24S-cholest-5-ene (3), were isolated from the CH2Cl2/EtOH extract of the South China Sea gorgonian coral Subergorgia reticulata. Their structures were established on the basis of extensive spectroscopic analysis. The absolute stereochemistry of compounds 2 and 3 was determined by the X-ray crystallographic analysis and the Mosher ester determination.

Three new briarane diterpenes, junceellonoids C - E (1 - 3), along with six known briaranes, junceellin A (4), praelolide (5), and junceellolides A-D (6 - 9), were isolated from the EtOH/CH2Cl2 extracts of the South China Sea gorgonian coral Junceella fragilis. The structures of 1 - 3 were established by extensive spectroscopic analysis, including 1D- and 2D-NMR data. Compounds I and 2 exhibited mild cytotoxicity against human galactophore carcinoma (MDA-mB-231 and MCF-7) cells at the concentration of 100 mu m.

Vascular endothelial growth factor receptor-2 (VEGFR-2) activation by VEGF-A is essential in vasculogenesis and angiogenesis. We have generated a pan-phosphorylation site map of VEGFR-2 and identified one major tyrosine phosphorylation site in the kinase insert (Y951), in addition to two major sites in the C-terminal tail (Y1175 and Y1214). In developing vessels, phosphorylation of Y1175 and Y1214 was detected in all VEGFR-2-expressing endothelial cells, whereas phosphorylation of Y951 was identified in a subset of vessels. Phosphorylated Y951 bound the T-cell-specific adapter (TSAd), which was expressed in tumor vessels. Mutation of Y951 to F and introduction of phosphorylated Y951 peptide or TSAd siRNA into endothelial cells blocked VEGF-A-induced actin stress fibers and migration, but not mitogenesis. Tumor vascularization and growth was reduced in TSAd-deficient mice, indicating a critical role of Y951-TSAd signaling in pathological angiogenesis.

Oxalicumones D (I) and E (II) are isolated along with the known oxalicumones A-B and five other known chromones from a culture broth of marine gorgonian-associated fungus Penicillium oxalicum SCSGAF 0023.

The free radicals generated from the iron containing system of xanthine oxidase and hypoxanthine (Fe-XO/HX) were directly detected by using spin trapping. It was found that not only superoxide anion (O2 −) and hydroxyl radical (OH ), but also alkyl or alkoxyl radicals (R ) were formed when saccharides such as glucose, fructose and sucrose were added into the Fe-XO/HX system. The generated amount of R was dependent on the kind and concentration of saccharides added into the Fe-XO/HX system and no R were detected in the absence of saccharides, indicating that there is an interaction between the saccharide molecules and the free radicals generated from the Fe-XO/HX system and saccharide molecules are essential for generating R in the Fe-XO/HX system. It is expected that the toxicity of R would be greater than of hydrophilic O2 − and OH because they are liposoluble and their lives are longer and the active sites of biomolecules are closely related with lipophilic phase, thus they can damage cells more seriously than O2 − and OH . The R generated from the saccharide containing Fe-XO/HX can be effectively scavenged by selenium containing abzyme (Se-abzyme), indicating Se-abzyme is a promising antioxidant.

Three new cyclic tetrapeptides, aspergillipeptides A-C (1-3), and one new asteltoxin B (4) were isolated from a culture broth of gorgonian-derived fungal strain Aspergillus sp. SCSGAF 0076. Their structures were elucidated by spectroscopic analysis, and the absolute configurations of aspergillipeptides A-C were determined by Marfey's method. Aspergillide C (3) showed strong antifouling activity against Bugula neritina larvae settlement with LC50/EC50>25. (c) 2013 Elsevier Ltd. All rights reserved.

Penispirolloid A (1), a novel alkaloid possessing a unique Spiro imidazolidinyl skeleton, was isolated from a halotolerant fungal strain. Penicillium sp. OUCMDZ-776. Its structure was elucidated on the basis of spectroscopic methods and quantum chemical CD calculation. Compound 1 showed significant antifouling activity toward Bugula neritina larvae with EC50 of 2.40 mu g/ml. Plausible biogenesis of compound 1 was also proposed. (C) 2012 Elsevier Ltd. All rights reserved.

isolation, structure determination and cytotoxicity of four new steroidal glycosides, muricellasteroids A—D (I), and related muricellasteroid E (II)

19 F NMR chemical shifts and coupling constants are given for a series of aryl (phenyl, naphthyl and phenanthryl) substituted trifluorovinyls and (E)- and (Z)-perfluoropropenyls. The relationship between the 19 F NMR chemical shifts and the configurational orientation of the perfluoroalkenyl substituents is discussed

Photolysis of γ-keto-α,β-unsaturated amides provides N-alkyl pyrrolidinones in high yield (77–;100%). The procedure is applicable to a variety of amides derived from the corresponding γ-keto acid.

The new compound macrolactin V (Ia) is isolated from the title bacillus together with the known diastereoisomer (Ib) and 3 other known compounds.

Catunaregin (1) and epicatunaregin (2), two novel norneolignans with a unique O-bridged furopyran ring, together with three known neolignans, ficusal, balanophonin, and 5″-methoxy-4″-O-(8-guaiacylglycerol)buddlenol A, were isolated from the stem bark of Catunaregam spinosa, a Chinese mangrove associate. Their structures were elucidated by spectroscopic means, including two-dimensional NMR techniques. Compounds 1 and 2 exhibited moderate inhibition against the mammary cancer F10 cell line.

Three new apo-tirucallols, 1alpha,7alpha-diacetoxyl-17alpha-20S-21,24-epoxy-apotirucall-14-ene-3alpha,23R,24S,25-tetraol (1), 7alpha-acetoxyl-17alpha-20S-21,24-epoxy-apotirucall-14-ene-3a,23R,24S,25-tetraol (2), 7alpha-acetoxyl-17alpha-20S-21,24-epoxy-apotirucall-14-en-3-one-23R,24S,25-triol (3) were obtained from the plants of the family Meliaceae. Their configurations were elucidated on the basis of extensive 1D and 2D NMR techniques in CD3OD solution. The equilibrium of the six-membered ring hemiacetal at side chain is also discussed. Finally, the stereochemistry of compound 1 was demonstrated by X-ray crystallography. (C) 2002 Elsevier Science Ltd. All rights reserved.

Two new quinoldione alkaloids, methyl 2-(3-hydroxy-1-methyl-2,4-dioxo-1,2,3,4-tetrahydroquinolin-3-yl)acetate (1) and 3-hydroxy-1-methyl-3-(2-oxopropyl)quinoline-2,4(1H,3H)-dione (2), and two quinolinone alkaloids previously synthesized but first isolated as natural products, N-methylflindersine (3) and 4-hydroxy-3-methoxy-1-methyl-2(1H)-quinolinone (4), were isolated from the stem bark of Micromelum falcatum, together with the known N-methylswietenidine-B (5). Their structures were established mainly on the basis of 1D- and 2D-NMR techniques. All compounds were evaluated for toxicity towards brine shrimp larvae, and 3 showed strong toxicity with an LD50 value of 1.39 mu g/ml.

A glassy carbon electrode having two polymer layers has been applied to selectively detect epinephrine. The inner layer formed by electropolymerization of macrocyclic nickel complex functioned as an electrocatalyst for epinephrine oxidation and the outer layer composed of hydrolyzed polyurethane γ-benzyl L-glutamate as a screening layer. Differential pulse voltammetry showed almost 100% recovery of epinephrine even in 100-fold excess of interferents. When applied to a dual glassy carbon electrode as an amperometric detector in flow injection analysis, a linear response over 0.1 μM and 10 μM was obtained. Recovery tested for 5-fold diluted human urine samples was 97.5%.

Two new iridoid glycosides with a lignan substituent, named scyphiphorins C (1) and D (2), were isolated from the stem bark of a Chinese mangrove Scyphiphora hydrophyllacea Gaertn. f., together with five known iridoid glycosides, 10-O-acetylgeniposidic acid (3), 7-deoxy-8-epi-loganic acid (4), mussaenoside (5), 7-deoxygardoside (6), and 10-deoxygeniposidic acid (7). The structures of compounds 1 and 2 were elucidated on the basis of spectroscopic data, especially 2D NMR techniques.

A new carbazole alkaloid, antipathine A (1), together with three known zoanthoxanthin alkaloids (2-4) was isolated from the EtOH/CH2Cl2 extracts of the South China Sea black coral Antipathes dichotoma. The structure of I was determined on the bases of extensive spectroscopic analysis, including 1 D and 2D NMR data. Compounds 1 and 2 showed moderate cytotoxicity against human stomach carcinoma SGC-7901 cell line with IC50 of 67.38 and 86.40 mu g/ml, respectively, and 1 and 2 also showed weak cytotoxicity toward human liver carcinoma Hep_G2 cell line.

Three new purine derivatives, namely, 4-caryboxy-5,6-dihydro-4H,8H-pyrimido[1,2,3-cd]purine-8,10(9H)-dione (1), 7,9-dihydro-1-(3-oxobutyl)-1H-purine-6,8-dione (2), and 7-hydro-9-(3-oxobutyl)-1H-purine-6,8-dione (3) together with six known purine and pyrimidine derivatives were isolated from the EtOH/CH2Cl2 extracts of the South China Sea gorgonian Subergorgia suberosa. The structures of 1—3 were determined on the bases of extensive spectroscopic analysis, including 1D and 2D NMR data.

Direct reduction of seven benzoic acids to alcohols via sodium borohydride–bromine (NaBH4–Br2) reagent was developed. The isolated yields for the seven acids to reduce reached 60.6–90.1%. This new synthesis route has the advantages of simple of application, low cost, mild nature, and satisfactory yields.

Two new iridoid glycosides, named scyphiphorins A (1) and B (2), together with four known compounds. geniposidic acid (= (1S, 4aS, 7aS)-1-(beta-D-glucopyranosyloxy)- 1,4a,5,7a-tetrahydro-7-(hydroxylmethyl)cyclopenta[c]pyr an-4-carboxylic acid; 3), 4-(4-hydroxy-3-methoxybenzyl)butan-2-one, oleanolic acid (=(3 beta)-3-hydroxyolean-12-en-28-oic acid). and stigmasterol beta-D-glucoside ( =(3 beta,22E)-stigmasta-5.22-dien-3-yl beta-D-glucopyranoside), were isolated for the first time from the stem bark of a Chinese mangrove. Scyphiphora hydrophyllacea GAERTN. f.. The structures of compounds I and 2 were determined as 10-O-benzoylgeniposidic acid and 10-O-[(2E, 6R)-8-hydroxy-2,6-dimethyl-1-oxooct-2-en-1-yl]geniposidic acid. respectively. on the basis of spectroscopic data and chemical methods, including 2D NMR techniques.

Ten new antifouling briarane diterpenoids, juncins R-ZI (1-10) were isolated from the South China Sea gorgonian coral Junceella juncea. The structures of these new compounds were established by extensive spectroscopic analysis, including 1D and 2D NMR data. Compounds 1-10 all showed potent antifouling activities against the larval settlement of barnacle Balanus amphitrite at nontoxic concentrations with EC50 values of 0.004, 0.34, 2.65, 1.61, 3.77, 21.06, 0.004, 0.14, 1.47, and 0.51 mu g mL(-1). The structure-activity relationship was discussed. (c) 2006 Elsevier Ltd. All rights reserved.

Two new polyoxygenated steroids, reticulatic acid (1) and reticulatin (2), together with a known compound 3,22,25-trihydroxy-16-24,20-24-bisepoxy-3 beta,16 beta,20S,22R,24S-cholest-5-ene (3), were isolated from the CH2Cl2/EtOH extract of the South China Sea gorgonian coral Subergorgia reticulata. Their structures were established on the basis of extensive spectroscopic analysis. The absolute stereochemistry of compounds 2 and 3 was determined by the X-ray crystallographic analysis and the Mosher ester determination.