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The fall armyworm (FAW) Spodoptera frugiperda is a severe economic pest of multiple crops globally. Control of this pest is often achieved using insecticides; however, over time, S. frugiperda has developed resistance to new mode of action compounds, including diamides. Previous studies have indicated diamide resistance is a complex developmental process involving multiple detoxification genes. Still, the mechanism underlying the possible involvement of microRNAs in post-transcriptional regulation of resistance has not yet been elucidated. In this study, a global screen of microRNAs (miRNAs) revealed 109 known and 63 novel miRNAs. Nine miRNAs (four known and five novel) were differentially expressed between insecticide-resistant and -susceptible strains. Gene Ontology analysis predicted putative target transcripts of the differentially expressed miRNAs encoding significant genes belonging to detoxification pathways. Additionally, miRNAs are involved in response to diamide exposure, indicating they are probably associated with the detoxification pathway. Thus, this study provides comprehensive evidence for the link between repressed miRNA expression and induced target transcripts that possibly mediate diamide resistance through post-transcriptional regulation. These findings highlight important clues for further research to unravel the roles and mechanisms of miRNAs in conferring diamide resistance. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW) Spodoptera frugiperda is a severe economic pest of multiple crops globally. Control of this pest is often achieved using insecticides; however, over time, S. frugiperda has developed resistance to new mode of action compounds, including diamides. Previous studies have indicated diamide resistance is a complex developmental process involving multiple detoxification genes. Still, the mechanism underlying the possible involvement of microRNAs in post-transcriptional regulation of resistance has not yet been elucidated. In this study, a global screen of microRNAs (miRNAs) revealed 109 known and 63 novel miRNAs. Nine miRNAs (four known and five novel) were differentially expressed between insecticide-resistant and -susceptible strains. Gene Ontology analysis predicted putative target transcripts of the differentially expressed miRNAs encoding significant genes belonging to detoxification pathways. Additionally, miRNAs are involved in response to diamide exposure, indicating they are probably associated with the detoxification pathway. Thus, this study provides comprehensive evidence for the link between repressed miRNA expression and induced target transcripts that possibly mediate diamide resistance through post-transcriptional regulation. These findings highlight important clues for further research to unravel the roles and mechanisms of miRNAs in conferring diamide resistance. [ABSTRACT FROM AUTHOR]

Drosophila suzukii Matsumura (Drosophilidae) is a devasting invasive pest affecting berry crops and cherry production throughout North America, South America, and Europe. This species has two different morph phenotypes, winter and summer morphs, which are temperature dependent. Chemical control is the most widely used management approach for managing the spotted wing drosophila, D. suzukii. Little is known regarding the differential response of the two seasonal morphs to insecticides. In this study, we identified a high number of differentially expressed genes likely involved in phase I, II, and III of detoxification pathways and other cuticular proteins in winter morphs as compared to summer morphs. Specifically, several detoxification genes (phase I: Cyp4e3, Cyp4s3, Cyp6d5, Cyp49a1, Cyp318a1; phase II: GstD10, Ugt35Bb, Ugt37b1, Ugt58Fa; phase III: Mdr65) were overexpressed more than two‐fold in winter morph. Additionally, we determined the median lethal concentration, LC50, values of Malathion, Cyantraniliprole, Imidan, Zeta‐cypermethrin, and Spinetoram insecticides to compare the insecticide susceptibility against two seasonal morphs of D. suzukii. For most of the pesticides tested, there were no differences between the LC50 values, between summer and winter morphs, however, we found that winter morph exhibited an LC50 value of Spinetoram 3.7‐fold, significantly higher than that of the summer morph. Overall, we demonstrated that seasonally induced different morphological phenotypes may result in different transcriptional response of phases I, II, and III of the detoxification pathways and other cuticular proteins. However, we found different responses to at least one insecticide, Spinetoram. It remains to be determined what are underlying physiological differences that lead to these changes in response to Spinetoram. [ABSTRACT FROM AUTHOR]

Insecticide-resistant Drosophila melanogaster strains represent a resource for the discovery of the underlying molecular mechanisms of cytochrome P450 constitutive over-expression, even if some of these P450s are not directly involved in the resistance phenotype. For example, in select 4,4’-dichlorodiphenyltrichloroethane (DDT) resistant strains the glucocorticoid receptor-like (GR-like) potential transcription factor binding motifs (TFBMs) have previously been shown to be associated with constitutively differentially-expressed cytochrome P450s, Cyp12d1, Cyp6g2 and Cyp9c1. However, insects are not known to have glucocorticoids. The only ortholog to the mammalian glucocorticoid receptor (GR) in D. melanogaster is an estrogen-related receptor (ERR) gene, which has two predicted alternative splice isoforms (ERRa and ERRb). Sequencing of ERRa and ERRb in select DDT susceptible and resistant D. melanogaster strains has revealed a glycine (G) codon insertion which was only observed in the ligand binding domain of ERR from the resistant strains tested (ERR-G). Transgenic flies, expressing the ERRa-G allele, constitutively over-expressed Cyp12d1, Cyp6g2 and Cyp9c1. Only Cyp12d1 and Cyp6g2 were over-expressed in the ERRb-G transgenic flies. Phylogenetic studies show that the G-insertion appeared to be located in a less conserved domain in ERR and this insertion is found in multiple species across the Sophophora subgenera. [ABSTRACT FROM AUTHOR]

Highlights: [•] We tested how natural variation affects the outcomes of RNAi treatments on insects. [•] Three field western corn rootworm populations and two genes were tested. [•] Effect of RNAi targeting a cysteine protease gene varied across populations. [•] RNAi of an immune gene caused opposite effects among populations feeding on soybean. [•] Natural variation among populations can alter the outcome of RNAi applications. [Copyright &y& Elsevier]

Abstract: Nucleic acid-sensing Toll-like receptors (TLRs) initiate innate immune responses to foreign RNA and DNA, yet can detect and respond to host DNA. To avoid autoimmune pathologies, nucleic acid sensing TLRs are tightly regulated. TLR9 primarily resides in the endoplasmic reticulum, traffics to endosomes, is proteolytically processed and responds to DNA. The heat shock protein gp96 is one of several accessory proteins that regulate intracellular trafficking of TLR9. In the absence of gp96, TLR9 fails to exit the endoplasmic reticulum, and therefore gp96-deficient macrophages fail to respond to CpG DNA. However, absence of gp96 precludes studies on potential chaperoning functions of gp96 for TLR9. Here we demonstrate that pharmacologic interference with gp96 function inhibits TLR9 signaling. TLR9 remains associated with gp96 during intracellular trafficking, and gp96-specific inhibitors increase TLR9 sensitivity to proteolytic degradation. We propose that gp96 is critical for both TLR9 egress from the ER, and for protein conformational stability in the endosomal compartment. These studies highlight the importance of examining gp96-specific inhibitors for modulating TLR9 activation, and the treatment autoimmune diseases. [Copyright &y& Elsevier]

Abstract: Attempts to prepare substituted chromones as novel retinoids revealed that some chromones were unstable under Wadsworth–Horner–Emmons reaction conditions. Hence, Wittig reactions were used to prepare chromone-based compounds as potential retinoids. Firstly, Wittig reagents prepared from 3-bromomethyl-chromen-4-one were reacted with olefinic-aldehydes to provide the target compounds with all-trans side chains in good yield. The approach supplies a useful general route to structurally diverse chromone-based compounds possessing a variety of side chains. Sequential Wittig reactions were used also to prepare a chromone-based retinoid. These novel compounds were evaluated in binding assays and a high affinity RAR ligand was identified. Crystal structures obtained for two key precursors aided the interpretation of binding data. [Copyright &y& Elsevier]

Abstract: Heat shock protein 90 (Hsp90) is an important target in cancer because of its role in maintaining transformation and has recently become the focus of several drug discovery and development efforts. While compounds with different modes of action are known, the focus of this review is on those classes of compounds which inhibit Hsp90 by binding to the N-terminal ATP pocket. These include natural product inhibitors such as geldanamycin and radicicol and synthetic inhibitors comprised of purines, pyrazoles, isoxazoles and other scaffolds. The synthetic inhibitors have been discovered either by structure-based design, high throughput screening and more recently using fragment-based design and virtual screening techniques. This review will discuss the discovery of these different classes, as well as their development as potential clinical agents. [Copyright &y& Elsevier]

Abstract: The preparation and magnetism of three supramolecular complexes, DABT-Ni2+/PAA, DABT-Cu2+/PAA and DABT-Fe2+/PAA, which were obtained via electrostatic interactions of the metal complexes of 2,2′-diaminos-4,4′-bithiazole (DABT-Ni2+, DABT-Cu2+and DABT-Fe2+) and poly(acrylic acid) (PAA) were described for the first time. FT-IR and elemental analysis were used to characterize the structures of the obtained materials. The magnetic behavior was examined as a function of magnetic field strength at 4K and as a function of temperature (4–300K). It was found that DABT-Ni2+/PAA and DABT-Cu2+/PAA exhibit ferromagnetic properties, while DABT-Fe2+/PAA exhibits an antiferromagnetic property. The corresponding multilayer films were also constructed on the quartz substrate. UV–vis spectra and AFM images were applied to characterize these thin films. The result indicates a process of uniform assembling. [Copyright &y& Elsevier]

Abstract: Poly(ε-caprolactone)s (PCLs) with various end-capping groups were prepared upon the novel one-pot reduction–initiation strategy. The reduction-involved ring-opening polymerization developed by Guillaume et al. has been firstly extended to aldehydes and ketones. The carbonyl compound was reduced by lanthanide borohydride (Nd or Y) to intermediate, which in situ triggered the ring-opening polymerization of ε-caprolactone. This one-pot strategy affords an efficient access to prepare the end-capped polymers from aldehydes or ketones. The reduction–initiation process and polymers were characterized by IR, NMR and SEC, and the possible mechanism was proposed. [Copyright &y& Elsevier]

Abstract: Magnetite (Fe3O4) nanoparticles were prepared by in situ precipitation and oxidation of ferrous ions in the presence of ω-functionalized polystyrenes having carboxylate, sulfonate, thiol, and thiolated groups. Based on the results for the orthogonal experimental design, both the ratio of the concentration of iron precursor to polymer and the reaction temperature were the major factors controlling the particle size and its shape morphology. By adjusting the reaction conditions, the iron oxide particle size can be effectively controlled in the range between 2 and 20nm. The magnetite-based polymer composite was characterized by UV–vis spectroscopy, thermogravimetric analysis, transmission electron microscopy, and X-ray diffraction. Magnetization measurements revealed that the nanocomposite materials exhibit superparamagnetic behavior at room temperature. [Copyright &y& Elsevier]

Abstract: Two novel copolymers containing bithiazole rings and ethylene oxide on the skeleton (PPOBTz and PNOBTz) were synthesized via Schiff reaction and Ullmann reaction, respectively. The copolymers were characterized by FTIR, 1H NMR. Their polymeric complexes with Cu2+ and Nd2+ were prepared. The magnetic behavior of these polymeric complexes was measured as a function of magnetic field strength (0–60kOe) at 4K and as a function of temperature (4–300K) at a magnetic field strength of 30kOe, indicating that they all exhibited features of soft ferromagnet. [Copyright &y& Elsevier]

large number of oilfield water samples were analyzed in this work. Research on the relationship between the concentrations and distribution of dissolved hydrocarbons suggested that the contents and composition of dissolved hydrocarbons varied with the hydrocarbon-generating potential of reservoirs. The concentrations of dissolved hydrocarbons were low in dry layers, water layers and gas-water layers, but high in gas reservoirs with oil reservoirs, especially in gas reservoirs with condensed oil. Series of carbon-number alkanes were usually absent in oilfield water from dry layers, water layers and gas-water layers but abundant in oilfield water from oil-water reservoirs, gas reservoirs and oil reservoirs, whose carbon numbers varied most widely in oil reservoirs and least in gas reservoirs. A preliminary evaluation model for reservoir hydrocarbon-generating potential was established based on the characteristics of dissolved hydrocarbons in oilfield water to assist hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

Abstract: The preparation and magnetic properties of three rare earth ions-modified multi-walled carbon nanotubes (MWNTs) were discussed. The materials MWNT-X3+ (X=Nd, Gd, Er) were prepared by the coordination of rare earth ions and oxidized MWNTs. A novel magnetic phenomena was observed at the applied field of 30kOe and at T =4K. With the increase of temperature, the value of magnetization decreases from positive to negative, and the magnetic state changes from quasi-ferromagnetism to diamagnetism, which does not follow the behaviors of conventional ferromagnets. [Copyright &y& Elsevier]

Abstract: The polymer (DAPcTPA) was synthesized by polycondensation of 5,6-diamine-1,10-phenanthroline (DAP) with terephthaldehyde (TPA). Three polymeric complexes were first prepared from polymer (DAPcTPA) and NiSO4, CoCl2 or FeSO4, respectively. The structures of polymer and complexes were characterized by IR, 1H NMR spectra and elemental analysis. The magnetic behavior of these complexes was measured as a function of magnetic field strength (0–50kOe) at 5K and as a function of temperature (5–300K) at a magnetic field strength of 30kOe. The results show that DAPcTPA-Ni2+ and DAPcTPA-Co2+ are soft ferromagnets, while DAPcTPA-Fe2+ exhibits features of an antiferromagnet. [Copyright &y& Elsevier]

Abstract: Two novel poly(Schiff base)s (PPHBT and PPHPHN) were prepared by polycondensation of 2,2′-diamino-4,4′-bithiazole (DABT), 5,6-diamino-1,10-phenanthroline (DAPH) with bisdecyloxyterephthaldehyde (BDTA), respectively. The structures of the poly(Schiff base)s were determined by IR and 1H NMR spectroscopy. The Nd3+ complexes of poly(Schiff base) were prepared and characterized. The contents of Nd for complexes were measured by complexometric titration. The magnetic behavior of the complexes was examined as a function of magnetic field strength at 4K and as a function of temperature (4–300K). The results show that both PPHBT-Nd3+ and PPHPHN-Nd3+ exhibit the characteristic of soft-magnetic materials at low temperature. [Copyright &y& Elsevier]

Abstract: Two novel fully conjugated polymers containing bithiazole rings (PDDBTz and PDABTz) were first synthesized by polycondensation of 2,7-dimethyl-2,4,6-octatriene-1,8-dial with 2,2′-bis(diethylphosphinatyl methyl)-4,4′-bithizole or 2,2′-diamino-4,4′-bithiazole (DABT). The structure of the polymers was determined by IR, 1H NMR and elemental analysis. PDDBTz is soluble in trifluoroacetic acid and DMSO, whereas PDABTz is soluble in common solvent such as THF, DMSO, DMF. Bithiazole rings were introduced to provide bidentate N-donor sites for binding metal ions. Their lanthanide metal complexes were prepared. The magnetic behavior of these polymeric complexes was measured as a function of magnetic field strength (0–60kOe) at 4K and as a function of temperature (4–300K) at magnetic field strength of 30kOe. The results show that they all exhibit features of soft ferromagnet. [Copyright &y& Elsevier]

A series of novel polyimide and poly(Schiff base) oligomers containing substituted bithiazole rings were designed and synthesized, for the first time, by polycondensation of 5,5′-dimethyl-2,2′- diamino-4,4′-bithiazole (MDABT) with dianhydrides (pyromellitic dianhydride, 3,3′-4,4′-benzophenone tetracarboxylic dianhydride and bis (3,4-dicarboxyphenyl) ether dianhydride), and dialdehydes (oxalic aldehyde, isophthalaldehyde and terephthalaldehyde). The structure of the oligomers was determined by IR and 1H NMR spectroscopy, and elemental analysis. The oligomers showed good thermal stability. The Fe2+ complex of poly(Schiff base), synthesized from MDABT with oxalic aldehyde (PMTOA), was prepared with 13.7% Fe content and found to be a ferromagnet at low temperature. [Copyright &y& Elsevier]

A novel complex of SWNT-PDTEN-Nd3+ was prepared though coordination action of polymer to introduce Nd3+ in SWNT-PDTEN system. The magnetic behavior of the complex was measured as a function of the magnetic field strength (0–60 kOe) at 5 K and a function of temperature (5–300 K). New magnetic phenomena of temperature dependence of magnetization for SWNT-PDTEN-Nd3+ are observed. The ferromagnetism of polymeric complex directly turns to diamagnetism at transition temperature of 125 K. It exhibits a hysteresis loop at 5 K with small coercivity (165 Oe) and remnant magnetization of 0.008 emu/g, which indicates that this complex possesses soft ferromagnetic property. [Copyright &y& Elsevier]

The preparation and magnetism of two rare earth polymeric complexes, PDTEN-Nd3+ and PMDTEN-Nd3+, which are obtained by polycondensation of -diamino--bithiazole (DABT) or -dimethyl--diamino--bithiazole (MDABT) with glyoxal and complexation of Nd3+ are described. New magnetic phenomena of temperature dependence and applied external field dependence of magnetization of the two complexes are observed in an applied field of 20 kOe and at . With temperature increasing, magnetization decreases to be negative above transition temperature, at which the magnetic state converts from ferromagnetism to diamagnetism. With applied field increasing, magnetization increases first then declines from maximum over turning point. These do not follow the behaviors expected of conventional ferromagnets. [Copyright &y& Elsevier]

Two polymeric ferro-complexes were first synthesized from FeSO4·7H2O and poly(Schiff base)s. The poly(Schiff base)s were prepared by polycondensation of 5,5′-dimethyl-2,2′-diamino-4,4′-bithiazole (MDABT) with oxalic aldehyde and isophthalaldehyde, respectively. The structures of polymers and complexes were characterized by IR and 1H NMR spectra. The Fe contents of complexes were measured by X-ray spectrometer. The magnetic behavior of the complexes was examined as a function of magnetic field strength at 4 K and as a function of temperature (4–300 K). The results show that PMTOA-Fe2+ is a soft ferromagnet while PMTIA-Fe2+ exhibits features of an antiferromagnet. [Copyright &y& Elsevier]

A new way was used to chemically synthesize a series of novel complexes of heteroaromatic polymer-connected SWNTs and metal ions (Fe2+, Nd3+). These derivations of SWNTs were characterized by Fourier transform infrared instrument (FTIR), elemental analysis (EA), the transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Raman spectrum, and better regularity is shown. Moreover, the magnetic behavior of these polymeric complexes was measured as a function of temperature (0–300 K) and as a function of magnetic field strength (0–40 kOe) at 5 K. The results of measurements indicate these complexes have special soft-ferromagnetic properties. [Copyright &y& Elsevier]

This paper describes the synthesis of a novel heterocyclic polymer incorporating both bithiazole and tetrathiapentalene moieties in the main chain. The complexion of the polymer with FeSO4 or NdCl3 in dimethyl sulfoxide produced corresponding metal complexes. Based on IR spectra and X-ray photoelectron spectroscopy (XPS) data the structure of these metal complexes is discussed briefly. The magnetic properties of the metallopolymers were measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K) under an applied magnetic field of 30 kOe, respectively. The neodymium complex exhibits a hysteresis cycle at 5 K, the observed coercivity Hc and the remnant magnetization Mr are 15 Oe and 0.00035 emu/g, respectively. [Copyright &y& Elsevier]

This paper describes the syntheses, structures and magnetic properties of novel bithiazole based polymeric complexes incorporating ferro ions and hexacyanoferrate groups. The polymer (referred to as SDP) is a condensed product, which obtained from the polycondensation of salicylic acid with 2,2′-diamino-4,4′-bithiazole (DABT) and paraformaldehyde. Its ferro-complex (SDP-Fe2+) reacted with potassium ferricyanide (K3[Fe(CN)6]) in DMSO, producing the polymeric–inorganic complex (SDP-Prussian blue). On the basis of preliminary characterization via spectroscopy techniques, reasonable structures have been proposed for these bithiazole based metallopolymers. The magnetic behavior of the polymeric complexes was measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K) at applied fields of 30 and 1000 Oe. SDP-Prussian blue exhibits a hysteresis cycle at 5 K, in which the observed coercive field (HC) is 40 Oe and the remnant magnetization (Mr) is 0.035 emu g−1. The results of measurements indicate that SDP-Fe2+ is an antiferromagnet, while SDP-Prussian blue shows a soft-ferromagnetic behavior. [Copyright &y& Elsevier]

AFLP markers in linkage disequilibrium with vH13, an avirulence gene in the Hessian fly (Mayetiola destructor) that conditions avirulence to resistance gene H13 in wheat (Triticum spp.), were discovered by bulked segregant analysis. Five AFLPs were converted into codominant site-specific markers that genetically mapped within 13 cM of this gene. Flanking markers used as probes positioned vH13 near the telomere of the short arm of Hessian fly chromosome X2. These results suggest that the X-linked avirulence genes vH6, vH9, and vH13 are present on Hessian fly chromosome X2 rather than on chromosome X1 as reported previously. Genetic complementation demonstrated that recessive alleles of vH13 were responsible for the H13-virulence observed in populations derived from four different states in the U.S.A.: Georgia, Maryland, Virginia, and Washington. Results support the hypothesis that a gene-for-gene interaction exists between wheat and Hessian fly.Key words: bulked segregant analysis, gene-for-gene interaction, wheat, Triticum, Mayetioladestructor.Des marqueurs AFLP montrant un déséquilibre de linkage avec le locus vH13, un gène d'avirulence chez la mouche de Hesse (Mayetiola destructor) qui détermine l'avirulence face au gène de résistance H13 chez le blé (Triticum spp.), ont été identifiés par analyse de ségrégants en mélange. Cinq marqueurs AFLP ont été convertis en marqueurs codominants spécifiques de locus et ont été localisés à moins de 13 cM (Kosambi) de ce gène. Des marqueurs bordant le gène ont été employés comme sonde et ont permis de situer le locus vH13 à proximité du télomère sur le bras court du chromosome X2. Ces résultats suggèrent que les gènes d'avirulence liés au chromosome X (vH6, vH9 et vH13) sont situés sur le chromosome X2 de la mouche de Hesse plutôt que sur le chromosome X1 tel qu'il avait été rapporté antérieurement. Une complémentation génétique a montré que les allèles récessifs de vH13 sont responsables de la virulence H13 observée chez des populations provenant de quatre états différents des États-Unis : la Georgie, le Maryland, la Virginie et l'état de Washington. Les résultats viennent appuyer l'hypothèse d'une relation gène-pour-gène entre le blé et la mouche de Hesse.Mots clés : analyse de ségrégants en mélange, interaction gène-pour-gène, blé, Triticum, Mayetiola destructor.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The copolymerization of N-phenylmaleimide (NPMI) with styrene (St) was studied with a rare earth coordination catalyst Nd(naph)3–AlEt3 in toluene at 50 °C. The compositions of the two monomers in copolymers were close to 1:1 even at a high monomer conversion of about 60%, and did not change as the NPMI feed mole fraction varied from 10% to 90%. The copolymer was characterized by 13C nuclear magnetic resonance spectroscopy, showing that the copolymer possessed a nearly alternating structure. The thermal properties of the copolymers were also investigated. It was presumed that a charge transfer complex of NPMI and St participated in the polymerization process. [Copyright &y& Elsevier]

A novel bithiazole oligomer (PCBT) was synthesized from C 60 and the diazo salt of 2,2′-diamino-4,4′-bithiazole (DABT). Its ferro-complex (PCBT-Fe 2+ ) was prepared from PCBT and FeSO 4 in DMSO solution under a purified nitrogen atmosphere. The magnetic behavior of PCBT and PCBT-Fe 2+ was measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. PCBT-Fe 2+ complex exhibits a hysteresis cycle at 5 K, the observed coercive field ( H C ) and remnant magnetization ( M r ) are 690 Oe and 0.12 emu/g, respectively. The results show that PCBT is an anti-ferromagnet and its Fe 2+ -complex is a soft ferromagnet. [ABSTRACT FROM AUTHOR]

Herbivorous insects encounter a variety of toxic environmental substances ranging from ingested plant defensive compounds to human-introduced insecticidal agents. Dietary antioxidants are known to reduce the negative physiological impacts of toxins in mammalian systems through amelioration of reactive oxygen-related cellular damage. The analogous impacts to insects caused by multigenerational exposure to pesticides and the effects on adaptive responses within insect populations, however, are currently unknown. To address these research gaps, we used Drosophila as a model system to explore adaptive phenotypic responses to acute dichlorodiphenyltrichloroethane (DDT) exposure in the presence of the dietary antioxidant vitamin C and to examine the structural genomic consequences of this exposure. DDT resistance increased significantly among four replicates exposed to a low concentration of DDT for 10 generations. In contrast, dietary intake of vitamin C significantly reduced DDT resistance after mutigenerational exposure to the same concentration of DDT. As to the genomic consequences, no significant differences were predicted in overall nucleotide substitution rates across the genome between any of the treatments. Despite this, replicates exposed to a low concentration of DDT without vitamin C showed the highest number of synonymous and non-synonymous variants (3196 in total), followed by the DDT plus vitamin C (1174 in total), and vitamin C alone (728 in total) treatments. This study demonstrates the potential role of diet (specifically, antioxidant intake) on adaptive genome responses, and thus on the evolution of pesticide resistance within insect populations. Unlabelled Image • Dietary intake of vitamin C significantly decreased DDT resistance following multigenerational low-dose DDT selection. • Dietary vitamin C impacted directional selection, decreasing the number of genomic synonymous and non-synonymous variants. • This study reveals that dietary antioxidants may, under some circumstances, impact the evolution of pesticide resistance. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the effects of a high body mass index (BMI) on the outcomes of radical gastrectomy for gastric cancer. Methods: We conducted a retrospective cohort study of 1729 patients with stage I to III gastric cancer who received open radical gastrectomy from February 2003 to August 2011. The patients were divided into 3 groups according to their BMI: a low BMI group (BMI < 18.5 kg/m2), normal BMI group (18.5 ≤ BMI < 25 kg/m2), and high BMI group (BMI ≥ 25 kg/m2). Results: A total of 871 patients were included in the final analysis, of which the median BMI was 22.7 kg/m2 (range 13.6–44.9 kg/m2). A high BMI increased the risk of postoperative intestinal fistula but not the risk of a reduced number of examined lymph nodes or hospital death. Furthermore, a high BMI did not negatively affect the overall survival (OS) of gastric cancer patients. Conclusions: A high BMI increased the operative morbidity after radical gastrectomy for gastric cancer. However, a high BMI did not negatively affect the quality of lymphadenectomy or the OS of gastric cancer patients in experienced high-volume centers. A careful approach during operation and meticulous perioperative management are required for gastric cancer patients with a high BMI. [ABSTRACT FROM AUTHOR]

Abstract: A convenient single-vessel conversion of primary and secondary alcohols to primary amines is reported. Use of this method results in substantially cleaner crude products than similar procedures reported in the literature. A simple work-up also makes this procedure ideal for parallel synthesis. [Copyright &y& Elsevier]

The adaptation of insect populations to insecticidal control is a continual threat to human health and sustainable agricultural practices, butmany complex genomicmechanisms involved in this adaption remain poorly understood. This study applied a systems approach to investigate the interconnections between structural and functional variance in response to dichlorodiphenyltrichloroethane (DDT) within the Drosophila melanogaster strain 91-R. Directional selection in 6 selective sweeps coincided with constitutive gene expression differences in DDT resistant flies, including the most highly upregulated transcript, Unc-115 b, which plays a central role in axon guidance, and the most highly downregulated transcript, the angiopoietin-like CG31832, which is involved in directing vascular branching and dendrite outgrowth but likely may be under trans-regulatory control. Direct functions and protein--protein interactions mediated by differentially expressed transcripts control changes in cellmigration, signal transduction, and gene regulatory cascades that impact the nervous system. Although changes to cellular stress response pathways involve 8 different cytochrome P450s, stress response, and apoptosis is controlled by a multifacetted regulatory mechanism. These data demonstrate that DDT selection in 91-R may have resulted in genome-wide adaptations that impacts genetic and signal transduction pathways that converge to modify stress response, cell survival, and neurological functions. This study implicates the involvement of a multigenic mechanism in the adaptation to a chemical insecticide, which impact interconnected regulatory cascades. We propose that DDT selection within 91-R might act systemically, wherein pathway interactions function to reinforce the epistatic effects of individual adaptive changes on an additive or nonadditive basis. [ABSTRACT FROM AUTHOR]

Maruca vitrata (Fabricius, 1787) is a cryptic pantropical species of Lepidoptera that are comprised of two unique strains that inhabit the American continents (New World strain) and regions spanning from Africa through to Southeast Asia and Northern Australia (Old World strain). In this study, we de novo assembled the complete mitochondrial genome sequence of the New World legume pod borer, M. vitrata, from shotgun sequence data generated on an Illumina HiSeq 2000. Phylogenomic comparisons were made with other previously published mitochondrial genome sequences from crambid moths, including the Old World strain of M. vitrata. The 15,385 bp M. vitrata (New World) sequence has an 80.7% A+T content and encodes the 13 protein-coding, 2 ribosomal RNA and 22 transfer RNA genes in the typical orientation and arrangement of lepidopteran mitochondrial DNAs. Mitochondrial genome-wide comparison between the New and Old World strains of M. vitrata detected 476 polymorphic sites (4.23% nucleotide divergence) with an excess of synonymous substitution as a result of purifying selection. Furthermore, this level of sequence variation suggests that these strains diverged from ~1.83 to 2.12 million years ago, assuming a linear rate of short-term substitution. The de novo assemblies of mitochondrial genomes from next-generation sequencing (NGS) reads provide readily available data for similar comparative studies. [ABSTRACT FROM AUTHOR]

Cowpea is a widely cultivated and major nutritional source of protein for many people that live in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include the pod sucking bugs, Anoplocnemis curvipes Fabricius (Hemiptera: Coreidae) and Clavigralla tomentosicollis Stål (Hemiptera: Coreidae); as well as phloem-feeding cowpea aphids, Aphis craccivora Koch (Hemiptera: Aphididae) and flower thrips, Megalurothrips sjostedti Trybom (Thysanoptera: Thripidae). Efforts to control these pests remain a challenge and there is a need to understand the structure and movement of these pest populations in order to facilitate the development of integrated pest management strategies (IPM). Molecular tools have the potential to help facilitate a better understanding of pest populations. Towards this goal, we used 454 pyrosequencing technology to generate 319,126, 176,262, 320,722 and 227,882 raw reads from A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. The reads were de novo assembled into 11,687, 7,647, 10,652 and 7,348 transcripts for A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. Functional annotation of the resulting transcripts identified genes putatively involved in insecticide resistance, pathogen defense and immunity. Additionally, sequences that matched the primary aphid endosymbiont, Buchnera aphidicola, were identified among A. craccivora transcripts. Furthermore, 742, 97, 607 and 180 single nucleotide polymorphisms (SNPs) were respectively predicted among A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti transcripts, and will likely be valuable tools for future molecular genetic marker development. These results demonstrate that Roche 454-based transcriptome sequencing could be useful for the development of genomic resources for cowpea pest insects in West Africa. [ABSTRACT FROM AUTHOR]

Metal coordinated micelles based on the diblock copolymer PHEMA 82 -b-HQ 78 were synthesized. The block PHQ with 8-hydroxyquinoline groups can coordinate with metal ions to form the crosslinked core for micellization, while the other block PHEMA in the shell of the micelle improves its solubility. The morphological characteristics and the coordinating interaction between the metal ions and the core segment were characterized by DLS and TEM. The magnetic measurement found that the Curie-Weiss temperature T θ of the metalized micelle was 56 K and its hysteresis loop exhibited the typical ‘S’ shape with low H c and M r at 5 K, indicating that this micelle had the properties of soft ferromagnetic materials. [ABSTRACT FROM AUTHOR]

Novel nanoparticles of coordination polymers (CPs) with various morphologies are successfully prepared. The obtained products can be well-dispersed to make films on glass substrates by the colloidal deposition method and introduced into methyl cellulose to produce transparent and luminescent films. [ABSTRACT FROM AUTHOR]

The chemotherapy of lymphatic filariasis relies upon drugs such as diethylcarbamazine and ivermectin that largely target the microfilarial stages of the parasite, necessitating continued treatment over the long reproductive life span of the adult worm. The identification of compounds that target adult worms has been a long-term goal of WHO. Here we describe a fluorescence polarization assay for the identification of compounds that target Hsp90 in adult filarial worms. The assay was originally developed to identify inhibitors of Hsp90 in tumor cells, and relies upon the ability of small molecules to inhibit the binding of fluorescently labelled geldanamycin to Hsp90. We demonstrate that the assay works well with soluble extracts of Brugia, while extracts of the free-living nematode C. elegans fail to bind the probe, in agreement with data from other experiments. The assay was validated using known inhibitors of Hsp90 that compete with geldanamycin for binding to Hsp90, including members of the synthetic purine-scaffold series of compounds. The efficacy of some of these compounds against adult worms was confirmed in vitro. Moreover, the assay is sufficiently sensitive to differentiate between binding of purine-scaffold compounds to human and Brugia Hsp90. The assay is suitable for high-throughput screening and provides the first example of a format with the potential to identify novel inhibitors of Hsp90 in filarial worms and in other parasitic species where Hsp90 may be a target. Author Summary: Helminth diseases of humans remain a major problem in many parts of the tropics. Treatment of these parasitic infections is restricted to a limited number of drugs and few new compounds are in development. One of the major obstacles to the development of new therapeutics is the lack of high-throughput screens that can be adapted to parasitic species for the identification of small molecule inhibitors. Here we present a simple, inexpensive assay for the identification of inhibitors of Hsp90 in filarial worms. The assay, first described for the identification of Hsp90 inhibitors in tumor cells, does not require recombinant protein but relies upon the ability of a fluorescently labelled drug to bind to Hsp90 in the context of a soluble fraction of worm homogenate. We validated the assay using known inhibitors of Hsp90, including derivatives of the synthetic purine-scaffold series of Hsp90 inhibitors and were able to show a differential sensitivity to these compounds between human and Brugia Hsp90. [ABSTRACT FROM AUTHOR]

The chemotherapy of lymphatic filariasis relies upon drugs such as diethylcarbamazine and ivermectin that largely target the microfilarial stages of the parasite, necessitating continued treatment over the long reproductive life span of the adult worm. The identification of compounds that target adult worms has been a long-term goal of WHO. Here we describe a fluorescence polarization assay for the identification of compounds that target Hsp90 in adult filarial worms. The assay was originally developed to identify inhibitors of Hsp90 in tumor cells, and relies upon the ability of small molecules to inhibit the binding of fluorescently labelled geldanamycin to Hsp90. We demonstrate that the assay works well with soluble extracts of Brugia, while extracts of the free-living nematode C. elegans fail to bind the probe, in agreement with data from other experiments. The assay was validated using known inhibitors of Hsp90 that compete with geldanamycin for binding to Hsp90, including members of the synthetic purine-scaffold series of compounds. The efficacy of some of these compounds against adult worms was confirmed in vitro. Moreover, the assay is sufficiently sensitive to differentiate between binding of purine-scaffold compounds to human and Brugia Hsp90. The assay is suitable for high-throughput screening and provides the first example of a format with the potential to identify novel inhibitors of Hsp90 in filarial worms and in other parasitic species where Hsp90 may be a target. [ABSTRACT FROM AUTHOR]

Abstract: The nanotube-based composite MWNT-Fe2+ was prepared through coordination action of the carboxylic acid groups from the oxidized multi-walled carbon nanotubes (MWNTs). The magnetic behavior of this composite was measured as a function of the magnetic field strength at 5K and a function of temperature (5–300K) at 30kOe. A hysteresis loop at 5K with a small coercivity of 260Oe was observed. The experimental results show that the MWNT-Fe2+ composite possesses special ferromagnetic interaction between nanotubes and iron ions. [Copyright &y& Elsevier]

Abstract: Ammonium-based ionic liquid monomers and their corresponding polymers [poly(ionic liquid)s] are synthesized and characterized for CO2 sorption. The polymers have much higher CO2 sorption capacities than the room-temperature ionic liquids and imidazolium-based poly(ionic liquid)s. For example, P[VBTMA][PF6] with polystyrene backbone has a CO2 sorption capacity of 10.67mol%. The CO2 sorption is selective over N2 and O2. The effects of cation, backbone, substituent, anion and crosslinking on CO2 sorption are discussed. The sorption mechanism study indicates that CO2 sorption by the poly(ionic liquid)s is a bulk and surface phenomenon. [Copyright &y& Elsevier]

Abstract: Anionic polymerizations of chiral N-phenylmaleimide derivatives bearing an oxazoline pendant (OPMI) were carried out with n-BuLi initiator to obtain optically active polymers. The polymer yields and specific optical rotations () were found to be significantly influenced by the reaction solvent, temperature, and the molar ratio of initiator to monomer. Particularly, the specific optical rotations exhibited a linear dependence on the molecular weights for the formed polymers, and the inversion from levo- to dextro-specific rotation was also observed with an increase in the molecular weights. On the basis of the results from circular dichroism (CD) and 13C NMR spectral analyses, the optical activity of poly(OPMI)s was attributed not only to the chirality of oxazolinyl groups in monomeric units but also to the partial helical structure due to an excess of threo-diisotactic configuration in the main chain. [Copyright &y& Elsevier]

The synthesis of π-conjugated poly(thiazole-2,4-diyl) (PTz) and its complexes incorporating lanthanide ions in the main chain (PTz–Nd3+, PTz–Gd3+) is described for the first time. FT-IR, 1H NMR, and elemental analysis were used to study the structure of the obtained materials. The magnetic properties of the polymeric complexes were measured as a function of temperature (3–300 K) under an applied magnetic field of 30 kOe, and the results indicated that there are ferromagnetic interactions between the metal ions. The complexes PTz–Nd3+ and PTz–Gd3+ have the Curie–Weiss temperature of 254 and 28 K, respectively. Both polymeric complexes exhibited a hysteresis loop at 5 K, the coercive field and remanence magnetization is, respectively, 51.4 Oe and 0.0033 emu/g for PTz–Nd3+; while corresponding values are 26.1 Oe and 0.018 emu/g for gadolinium complex. [Copyright &y& Elsevier]

The paper presents the polymerization of acrylonitrile (AN) initiated by samarium diiodide (SmI2) combining with hexamethylphosphoramide (HMPA) for the first time. The effects of various parameters, such as reaction temperature, AN/Sm and HMPA/Sm molar ratios, reaction time on the polymer yield and its molecular weight were discussed. On the basis of both IR and NMR analysis of resulted polymers, a single-electron-transfer initiation mechanism of AN as radical anion was proposed for this polymerization, which was further sustained by the copolymerization of AN with &epsiv;-caprolactone and 2,2-dimethyltrimethylene carbonate, respectively. [Copyright &y& Elsevier]

Insecticide resistance is an ongoing challenge in agriculture and disease vector control. Here, we demonstrate a novel strategy to attenuate resistance. We used genomics tools to target fundamental energy-associated pathways and identified a potential "Achilles' heel" for resistance, a resistance-associated protein that, upon inhibition, results in a substantial loss in the resistance phenotype. Specifically, we compared the gene expression profiles and structural variations of the insulin/insulin-like growth factor signaling (IIS) pathway genes in DDT-susceptible (91-C) and -resistant (91-R) Drosophila melanogaster (Drosophila) strains. A total of eight and seven IIS transcripts were up- and down-regulated, respectively, in 91-R compared to 91-C. A total of 114 nonsynonymous mutations were observed between 91-C and 91-R , of which 51.8% were fixed. Among the differentially expressed transcripts, phosphoenolpyruvate carboxykinase (PEPCK), down-regulated in 91-R , encoded the greatest number of amino acid changes, prompting us to perform PEPCK inhibitor–pesticide exposure bioassays. The inhibitor of PEPCK, hydrazine sulfate, resulted in a 161- to 218-fold decrease in the DDT resistance phenotype (91-R) and more than a 4- to 5-fold increase in susceptibility in 91-C. A second target protein, Glycogen synthase kinase 3β (GSK3β-PO), had one amino acid difference between 91-C and 91-R , and the corresponding transcript was also down-regulated in 91-R. A GSK3β-PO inhibitor, lithium chloride, likewise reduced the resistance but to a lesser extent than did hydrazine sulfate for PEPCK. We demonstrate the potential role of IIS genes in DDT resistance and the potential discovery of an "Achilles' heel" against pesticide resistance in this pathway. Unlabelled Image • 114 nonsynonymous mutations, for genes within the insulin signally pathway, were observed between 91-C and 91-R. • PEPCK had the greatest number of amino acid differences identified between 91-C and 91-R. • Inhibitor of PEPCK (hydrazine sulfate) resulted in a 161- to 218-fold decrease in 91-R. • The nutritional status of flies influenced the toxicity of DDT and the effectiveness of inhibitors on resistance levels. [ABSTRACT FROM AUTHOR]

Insects experience a diversity of subtoxic and/or toxic xenobiotics through exposure to pesticides and, in the case of herbivorous insects, through plant defensive compounds in their diets. Many insects are also concurrently exposed to antioxidants in their diets. The impact of dietary antioxidants on the toxicity of xenobiotics in insects is not well understood, in part due to the challenge of developing appropriate systems in which doses and exposure times (of both the antioxidants and the xenobiotics) can be controlled and outcomes can be easily measured. However, in Drosophila melanogaster, a well-established insect model system, both dietary factors and pesticide exposure can be easily controlled. Additionally, the mode of action and xenobiotic metabolism of dichlorodiphenyltrichloroethane (DDT), a highly persistent neurotoxic organochlorine insecticide that is detected widely in the environment, have been well studied in DDT-susceptible and -resistant strains. Using a glass-vial bioassay system with blue diet as the food source, seven compounds with known antioxidant effects (ascorbic acid, β-carotene, glutathione, α-lipoic acid, melatonin, minocycline, and serotonin) were orally tested for their impact on DDT toxicity across three strains of D. melanogaster: one highly susceptible to DDT (Canton-S), one mildly susceptible (91-C), and one highly resistant (91-R). Three of the antioxidants (serotonin, ascorbic acid, and β-carotene) significantly impacted the toxicity of DDT in one or more strains. Fly strain and gender, antioxidant type, and antioxidant dose all affected the relative toxicity of DDT. Our work demonstrates that dietary antioxidants can potentially alter the toxicity of a xenobiotic in an insect population. [ABSTRACT FROM AUTHOR]

The development of a catalyst for the selective catalytic reduction (SCR) of NO x is essential for purifying air and the denitration of coal-burning exhaust. Herein, we prepare novel MnO x -CeO2 nanosheets with porous structures by a homogeneous coordination precipitation (HCP) method which exhibit a high NO removal efficiency above 90 % in the SCR reaction at low temperature (150–240°C). The MnO x -CeO2(HCP) catalysts have a higher Brunauer–Emmett–Teller (BET) surface area and more homogeneous distribution of Mn x+ in the CeO2 lattice than those prepared by co-precipitation and precursor mixture combustion methods according to BET, X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy characterizations. Together with a higher ratio of Mn4+, Ce3+, and Oα, the above properties are responsible for the high catalytic performances of MnO x -CeO2(HCP) in the SCR of NO x. Well defined MnO x -CeO2 nanosheets with porous structures obtained by a homogeneous coordination precipitation method exhibit a high NO removal efficiency above 90 % in the SCR reaction at a low temperature of 150°C. [ABSTRACT FROM AUTHOR]

We report a facile preparation method of Ti‐doped CeO2 nanosheets and their use as supports for palladium (Pd) deposition. The nanosheets were fabricated by the coordination‐precipitation method, and Pd nanoparticles were placed on the surfaces in situ. The obtained Pd‐loaded nanosheets TixCe1–xO2‐Pd were applied as catalysts in the hydrogenation of 4‐nitrophenol (4‐NP). While the catalyst supported by pure CeO2 nanosheets exhibited a 4‐NP conversion of 40 % in 10 min, doping a small amount of Ti into the support led to a faster 4‐NP reduction of 80 % in 10 min and quantitative conversion in 30 min. The hydrogenation of 4‐NP catalyzed by Ti0.1Ce0.9O2‐Pd exhibited a relatively high apparent reaction rate constant (k = 0.134 min‐1). This high catalytic activity could be attributed to the synergetic effect of the Pd nanoparticles with high dispersion and the TixCe1–xO2 supports with high oxygen vacancies. Furthermore, these catalysts displayed high reproducibility and chemical stability: they can be recycled and reused for at least 5 times with negligible loss of catalytic activity. [ABSTRACT FROM AUTHOR]

A one-pot “grafting-from” strategy is presented to prepare AB- and ABA-type bottlebrush block copolymers (BBCPs). Precursor block copolymers with pendant dithiocarbamate and hydroxyl groups were synthesized as the macroinitators. Polylactide (PLA) and poly(N-vinylpyrrolidone) (PVP) side chains were grafted by ring-opening polymerization (ROP) and reversible addition-fragmentation chain-transfer (RAFT) polymerization in one pot, respectively. Molecular weight control was achieved as evidenced by gel permeation chromatography (GPC) and 1 H nuclear magnetic resonance ( 1 H NMR). The length of side chains in each block (DP from 8 to 113) could be facilely tuned by polymerization conditions such as the reaction time and the feed ratio of monomer to initiator, leading to various molecular morphologies observed by atomic force microscopy (AFM). This synthetic strategy is flexible and adaptable, allowing convenient access to customized macromolecular architecture. [ABSTRACT FROM AUTHOR]