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A large number of studies have indicated that Astragalus Membranaceus (AM) possesses growth-promoting effects in animal husbandry. However, the function of AM in common carp growth performance has not meant fully evaluated. In this work, to investigate the potential effects of AM and Lactobacillus plantarum-fermented AM (FAM) on growth performance, intestinal function, and intestinal microenvironment of common carp, fish with an average weight of 10.10 ± 0.25 g were divided into seven groups, and fed daily with an additive-free basal diet (BD); 0.1%, 0.2%, and 0.4% (w/w) of AM (L-AM, M-AM, and H-AM); 0.1%, 0.2%, and 0.4% (w/w) of FAM (L-FAM, M-FAM and H-FAM) for an eight-week period. The results showed that incorporating L-AM or L-FAM in the diet significantly increased (P

[This corrects the article DOI: 10.1371/journal.pone.0156260.].

Chronic myeloid leukemia (CML) is a myeloproliferative disease. Imatinib (IM), the first line treatment for CML, is excessively expensive and induces various side effects in CML patients. Therefore, it is essential to investigate a new strategy for improving CML therapy. Our immunoblot data revealed that RanGTPase activating protein 1 (RanGAP1) protein levels increased by approximately 30-fold in K562 cells compared with those in normal cells. RanGAP1 is one of the important components of RanGTPase system, which regulates the export of nuclear protein. However, whether RanGAP1 level variation influences BCR-ABL nuclear export is still unknown. In this report, using shRNA to downregulate RanGAP1 expression level augmented K562 cell apoptosis by approximately 40% after treatment with 250 nM IM. Immunofluorescence assay also indicated that three-fold of nuclear BCR-ABL was detected. These data suggest that BCR-ABL nuclear entrapment induced by RanGAP1 downregulation can be used to improve IM efficacy. Moreover, our qRT-PCR data indicated a trend of inverse correlation between the RanGAP1 and microRNA (miR)-1301 levels in CML patients. MiR-1301, targeting the RanGAP1 3' untranslated region, decreased by approximately 100-fold in K562 cells compared with that in normal cells. RanGAP1 downregulation by miR-1301 transfection impairs BCR-ABL nuclear export to increase approximately 60% of cell death after treatment of 250 nM IM. This result was almost the same as treatment with 1000 nM IM alone. Furthermore, immunofluorescence assay demonstrated that Tyr-99 of nuclear P73 was phosphorylated accompanied with nuclear entrapment of BCR-ABL after transfection with RanGAP1 shRNA or miR-1301 in IM-treated K562 cells. Altogether, we demonstrated that RanGAP1 downregulation can mediate BCR-ABL nuclear entrapment to activate P73-dependent apoptosis pathway which is a novel strategy for improving current IM treatment for CML.

A solution-processable functional polyimide (PYTPA-PI) containing triphenylamine-substituted diphenylpyridine moieties (PYTPA) and phthalimide moieties (PI) is prepared and analyzed. The electronic transitions and transport mechanisms associated with the memory effect are analyzed and the electrical switching performance in PYTPA-PI has illustrated the possibility of tuning memory properties in imide polymers.

Two novel near-infrared (NIR) electrochromic polynorbornenes, poly(NBDTPA) and poly(HNBDTPA), containing electroactive chromophores, were prepared viaring-opening metathesis polymerisation from a new norbornene derivative (NBDTPA) using Grubbs' catalysts followed by hydrogen reduction. The glass transition temperatures (Tg) of poly(NBDTPA) and hydrogenated poly(HNBDTPA) were 141 °C and 91 °C, respectively. The 10% weight-loss temperatures of hydrogenated poly(HNBDTPA) and poly(NBDTPA) were up to 440 °C and 397 °C, respectively. Hydrogenated poly(HNBDTPA) film showed excellent transparency (up to 91%). Poly(NBDTPA) showed a cyclic voltammogram and electrochromic behaviour that was similar to poly(HNBDTPA). The cyclic voltammogram of a poly(HNBDTPA) film cast onto an indium-tin oxide (ITO)-coated glass substrate exhibited three reversible oxidation redox couples at 0.63, 0.82 and 1.23 V vs.Ag/Ag+in acetonitrile solution. The electrochromic characteristics of poly(HNBDTPA) showed excellent stability and reversibility, with multi-stage colour changes from its colourless neutral form to green, light-blue and dark-blue with applied potentials of 0 to 1.75 V. The colour switching time and bleaching time of the poly(HNBDTPA) were 7.1 s and 4.2 s in the near-infrared region (1230 nm), and 7.4 s and 4.5 s in the UV-vis region (420 nm), respectively. [ABSTRACT FROM AUTHOR]

This work reports the synthesis and characterization of a series of functional aromatic polyimides (OXTA-PI)s containing triphenylamine and 1,3,4-oxadiazole moieties. All the polyimides exhibit high glass transition temperatures of 309−319 °C. A resistive switching device with the sandwich structure of indium−tin oxide/polymer/Al was fabricated using the soluble polyimide from 4,4′-hexafluoroisopropylidenediphthalic anhydride (OXTA-PIa). The device exhibits two conductivity states and can be switched from the initial low-conductivity (OFF) state to the high-conductivity (ON) state at the threshold voltages of 1.8 V under both positive and negative electrical sweeps, with an ON/OFF state current ratio in the order of 105. The ON state of the device is nonvolatile and can withstand a constant voltage stress of −1 V for 6 h and 108pulse read cycles at −1 V under ambient conditions. Upon reversing the bias, the ON state cannot be reset to the initial OFF states. The nonvolatile and inerasable nature of the ON state, as well as the ability to write, read, and sustain the electrical states, fulfills the requirements of a write-once read-many-times (WORM) memory. [ABSTRACT FROM AUTHOR]

A solution-processable functional polyimide, P(BPPO)-PI, containing oxadiazole moieties (electron donors) and phthalimide moieties (electron acceptors) was synthesized. A switching device, based on a solution-cast thin film of P(BPPO)-PI sandwiched between an indium−tin oxide (ITO) bottom electrode and an Al top electrode, exhibits two accessible conductivity states and can be switched from the low-conductivity (OFF) state to the high-conductivity (ON) state when swept positively or negatively, with an ON/OFF current ratio on the order of 1 × 104. The device exhibits ON state “remanence”, with the ON state retainable for a period of about 4 min after turning off the power. The ON state can be electrically sustained either by a refreshing voltage pulse of −1 V or by a continuous bias of −1 V. The “remanent” but volatile nature of the ON state and the ability to write, read, and sustain the electrical states with bias are characteristic features observed in a static random access memory (SRAM). The mechanisms associated with the memory effect were elucidated from molecular simulation results and changes in the photoelectronic spectrum of P(BPPO)-PI film when the device was switched between the ON and OFF states. [ABSTRACT FROM AUTHOR]

Pure exo‐functional norbornene monomers containing various chromophores such as fluorene, pyrene, and carbazole were successfully prepared via the Diels–Alder reaction and condensation reaction. The living ring‐opening metathesis polymerization (ROMP) of a fluorene‐containing monomer, exo‐2‐(fluorene‐9‐ylcarboxymethyl)norborn‐5‐ene (exo‐1), was observed and confirmed by the formation of a diblock copolymer and a linear relationship between the number‐average molecular weight and [M]/[I] ratios ([M] = monomer concentration; [I] = initiator concentration). The synthesis and characteristics of novel fluorene‐containing polymers based on pure exo‐1 are reported with Grubbs catalyst I {RuCl2(CHPh)[P(C6H11)3]2} with a high molecular weight of 3.18 × 104 in 90 s ([M]/[I] = 100). However, the ROMP of pyrene‐ and carbazole‐containing monomers [exo‐5‐(pyrene methoxy carbonyl)bicyclo[2.2.1]hept‐2‐ene and exo‐5‐(carbazole ethoxy carbonyl)bicyclo[2.2.1]hept‐2‐ene, respectively] were carried out in a nonliving fashion. All the chromophore‐containing polymers showed excellent solubility in various organic solvents, particularly in chloroform, N‐methyl‐2‐pyrrolidinone, and 1,2‐dichlorobenzene. The glass transition temperatures of polynorbornenes containing various chromophores were determined to be 80–109 °C (by differential scanning calorimetry) higher than that of ring‐opened polynorbornene (glass transition temperature = 35 °C), indicating that the incorporation of the pendant aromatic moieties (e.g., fluorene, pyrene, and carbazole) could enhance the transition temperature for segmental motions of polymer chains. The photoluminescence spectra of all polymer solutions showed a strong emission in the blue region of the visible spectra. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3022–3031, 2007 [ABSTRACT FROM AUTHOR]

A new diamine containing a pyridine heterocyclic group and a naphthalene substituent, 4‐(2‐naphthyl)‐2,6‐bis(4‐aminophenyl) pyridine (NBAPP), was synthesized with the Chichibabin reaction and used in the preparation of poly(pyridine imide) by direct polycondensation with 4,4′‐hexafluoroisopropylidenediphathalic anhydride in N‐methyl‐2‐pyrrolidinone (NMP). The poly(pyridine imide) derived from diamine NBAPP with naphthalene substituents was highly organosoluble: it was soluble in tetrahydrofuran, NMP, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, and γ‐butyrolactone at room temperature and in pyridine, dimethyl sulfoxide, and cyclohexanone upon heating at 70 °C. The poly(pyridine imide) was converted into lightly colored, optically transparent, flexible, and tough polyimide films via casting onto glass from a DMAc solution. This polymer exhibited good thermal stability (temperature of 10% weight loss = 527 °C) in air and high dielectric constants (as high as 4.20 at 1 kHz). The polyimide films had a tensile strength of 102 MPa and a tensile modulus of 1.8 GPa. As for the optical properties, the polymer exhibited UV–vis absorption bands in the region of 223–450 nm and possessed strong green‐yellow fluorescence (500 nm) after being protonated with acid. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2367–2374, 2007 [ABSTRACT FROM AUTHOR]

A new diamine containing a pyridine heterocyclic group and a pyrene substituent, 4-(1-pyrene)-2,6-bis(4-aminophenyl)pyridine (PBAPP), was synthesized and used in a preparation of poly(pyridine−imide) by direct polycondensation with 4,4‘-hexafluoroisopropylidenediphathalic anhydride (6FDA) in N-methyl-2-pyrrolidinone (NMP). The poly(pyridine−imide) derived from diamine (PBAPP) was highly soluble in several solvents such as THF, NMP, DMAc, DMF, pyridine, DMSO, and cyclohexanone at room temperature or upon heating at 70 °C and exhibited good thermal stability both in nitrogen and air (Td10>520 °C) and a high dielectric constant of 4.32 at 1 kHz. The poly(pyridine−imide) could be cast into a flexible and tough film from DMAc solution. The poly(pyridine−imide) film had a tensile strength of 118 MPa and a tensile modulus of 2.2 GPa. The optical properties exhibited the UV−vis absorption bands at the region of 200−400 nm and possessed strong orange fluorescent (560 nm) after protonated with protic acid. [ABSTRACT FROM AUTHOR]

Aromatic polyamides with multi amino end groups were prepared from a novel triamine (II) (BBB) and dicarboxylic acids (A2) in the presence of (2,3-dihydro-2-thioxo-3-benzoxazolyl) phosphonic acid diphenyl ester (DBOP) as a condensing agent. The corresponding polyamides were obtained in quantitative yields with inherent viscosities of 0.400.42 dL g-1. The structure of the polyamides with low degree of branching was confirmed by nuclear magnetic resonance and by infrared spectroscopy. The amino terminal groups of the polymers were modified by reacting with acetyl chloride, benzoyl chloride and phthalic anhydride to give terminally modified polyamides. Although the degree of branching was as small as 0.05, their solubility in amide solvents was clearly improved. The end group modification of the polyamides greatly affected the thermal properties. Strong but brittle films were prepared by casting from N,Ndimethylformamide (DMF) solution. The mechanical properties were comparable with those of corresponding linear polymers. [ABSTRACT FROM AUTHOR]

Hyperbranched polyamides with different degree of branchings (DBs) were prepared by different polycondensation conditions from an ABB' type monomer, 4-(2,4-diaminophenoxy)benzoic acid. Polyamide (PAl) with multi-amino groups prepared in the presence of (2,3-dihydro-2-thioxo-3-benzoxazolyl) phosphonic acid diphenyl ester (DBOP) and triethylamine as condensing agents at room temperature had lower DB of 0.1. Polyamide (PA2) with multi-amino groups prepared in the presence of triphenylphosphite and pyridine as condensing agent at 100°C had higher DB of 0.2. The free amino groups of both polyamides were modified by acetyl chloride, benzoyl chloride and phthalic anhydride, respectively, to give corresponding modified polyamides. The solubility and thermal properties were not influenced by the different DBs but were influenced by the end groups. Strong films were prepared from polyamides with lower DBs and polyamides with amino groups. [ABSTRACT FROM AUTHOR]