Vagal Transient Receptor Potential Ankyrin 1 Mediates Stress-exacerbated Visceral Mechanonociception After Antral Cold Exposure

Xin Chen,Qingqing Luo,Xiujuan Yan,Wenting Li,Shengliang Chen 대한소화기 기능성질환∙운동학회 2019 Journal of Neurogastroenterology and Motility (JNM Vol.25 No.3

Background/AimsAbdominal pain can be evoked or exacerbated after gastrointestinal cold stimulation in some patients with diarrhea-predominantirritable bowel syndrome (IBS-D), indicating a low temperature-induced sensitization of visceral perception. We investigated the roleof vagal transient receptor potential ankyrin 1 (TRPA1, a cold-sensing ion channel) in cold-aggravated visceral mechanonociception ina stress-induced IBS animal model. MethodsTRPA1 expression was examined in antral biopsies of healthy controls and IBS-D patients. Abdominal symptoms were assessed beforeand after warm or cold water intake. The visceromotor response (VMR) to colorectal distention (CRD) following intra-antral infusionof cold saline was measured in animals undergoing sham or chronic water avoidance stress. TRPA1 expression, extracellular signalregulatedprotein kinase 1/2 (ERK1/2) phosphorylation, and neuronal calcium influx in vagal afferents were assessed. ResultsCompared to healthy controls, IBS-D patients displayed elevated antral TRPA1 expression, which was associated with symptom scoresafter cold (4°C) water intake. Intra-antral infusion of cold saline increased VMR to CRD in naive rats, an effect dependent on vagalafferents. In stressed rats, this effect was greatly enhanced. Functional blockade and gene deletion of TRPA1 abolished the cold effecton visceral nociception. TRPA1 expression in vagal (but not spinal) afferents increased after stress. Moreover, the cold-induced, TRPA1-dependent ERK1/2 activation and calcium influx in nodose neurons were more robust in stressed rats. ConclusionsStress-exaggerated visceral mechanonociception after antral cold exposure may involve up-regulation of TRPA1 expression andfunction on vagal afferents. Our findings reveal a novel mechanism for abnormal gastrointestinal cold sensing in IBS.

β-Actin regulates interleukin 6-induced p21 transcription by interacting with the Rpb5 and Rpb7 subunits of RNA polymerase II

Xiujuan Tian,Wenjing Qi,Hongyu Chen,Xianlu Zeng,Liping Han,Donghui Mi 한국통합생물학회 2016 Animal cells and systems Vol.20 No.5

In pre-initiation complexes, RNA helicase A interacts with β-actin and acts as a bridging factor linking nuclear actin with RNA polymerase II (Pol II). In addition, β-actin participates in Pol IIdependent transcription elongation by interacting with the positive transcription elongation factor Cdk9. However, many relationships between β-actin and Pol II remain to be identified. In an interleukin 6 (IL-6)-induced p21 expression model, we demonstrated that β-actin knockdown reduced p21 expression. Immunofluorescence analysis showed that the colocalization of β-actin and Pol II increased significantly in cells treated with IL-6. It is known that the Rpb5, Rpb6 and Rpb7 subunits are located at the surface of the enzyme. We next constructed recombinant pcDNA-HA-Rpb5, pcDNA-HA-Rpb6 and pcDNA-HA-Rpb7 plasmids and expressed the three polymerase II subunits in HepG2 cells. We found that β-actin could be immunoprecipitated with HA-Rpb5 and HA-Rpb7. A Glutathione-S-transferase pull-down assay revealed that β-actin was associated with Rpb5 and Rpb7 in vitro. Furthermore, overexpression of Rpb5 and Rpb7 in cells reduced p21 expression significantly, suggesting that Rpb5 and Rpb7 competitively interact with β-actin. This study shows that β-actin associates with Pol II subunits through direct proteinprotein interactions and provides fundamental insight into Pol II transcriptional regulation.

Characteristics of lipoxygenase-based and lipoxygenase-deficient soy yogurt with modified okara

Xiujuan Wang,Yue Chen,Yuhua Wang,Weichang Dai,Chun Hong Piao,Hansong Yu 한국식품과학회 2021 Food Science and Biotechnology Vol.30 No.13

Lipoxygenase-based and lipoxygenase-deficientokara were modified by Kluyveromyces marxianus fermentation,then adding modified okara back to the correspondingsoymilk to prepare soy yogurt. Thephysicochemical properties, texture, and volatile componentsof soy yogurt were characterized. The results showedthat okara modified by Kluyveromyces marxianus fermentationwas rich in soluable dietary fiber and was impartedbetter water-holding capacity, swelling capacity, and oilholdingcapacity. The soy yogurt with the modified okarawas greatly enhanced in its appearance, texture and wasrelatively stable during storage. Moreover, lipoxygenasebasedsoy yogurt had a unique soybean flavor whilelipoxygenase-deficient soy yogurt had a slight beany flavorand soybean flavor. This article guides a bio-modifiedmethod for okara and provides a theoretical basis for thefurther development and application of soy yogurt withhigh dietary fiber as well as lipoxygenase-deficient soyyogurt.

A Mononuclear Non-Heme Manganese(IV)–Oxo Complex Binding Redox-Inactive Metal Ions

Chen, Junying,Lee, Yong-Min,Davis, Katherine M.,Wu, Xiujuan,Seo, Mi Sook,Cho, Kyung-Bin,Yoon, Heejung,Park, Young Jun,Fukuzumi, Shunichi,Pushkar, Yulia N.,Nam, Wonwoo American Chemical Society 2013 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.135 No.17

<P>Redox-inactive metal ions play pivotal roles in regulating the reactivities of high-valent metal–oxo species in a variety of enzymatic and chemical reactions. A mononuclear non-heme Mn(IV)–oxo complex bearing a pentadentate N<SUB>5</SUB> ligand has been synthesized and used in the synthesis of a Mn(IV)–oxo complex binding scandium ions. The Mn(IV)–oxo complexes were characterized with various spectroscopic methods. The reactivities of the Mn(IV)–oxo complex are markedly influenced by binding of Sc<SUP>3+</SUP> ions in oxidation reactions, such as a ∼2200-fold increase in the rate of oxidation of thioanisole (i.e., oxygen atom transfer) but a ∼180-fold decrease in the rate of C–H bond activation of 1,4-cyclohexadiene (i.e., hydrogen atom transfer). The present results provide the first example of a non-heme Mn(IV)–oxo complex binding redox-inactive metal ions that shows a contrasting effect of the redox-inactive metal ions on the reactivities of metal–oxo species in the oxygen atom transfer and hydrogen atom transfer reactions.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2013/jacsat.2013.135.issue-17/ja312113p/production/images/medium/ja-2012-12113p_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja312113p'>ACS Electronic Supporting Info</A></P>

Enhanced dielectric properties and discharged energy density of composite films using submicron PZT particles

Chen, Guanliang,Lin, Xiujuan,Li, Jianan,Fisher, John G.,Zhang, Yan,Huang, Shifeng,Cheng, Xin Elsevier 2018 CERAMICS INTERNATIONAL Vol.44 No.13

<P><B>Abstract</B></P> <P>Flexible dielectric composite films are highly desirable materials with potential application in capacitors due to their high energy density and discharged efficiency. However, agglomeration induced by the large surface energy of nanoparticles and their large dielectric losses are unfavorable to the improvement of energy density. Submicron lead zirconate titanate (PZT) particles have shown great potential as filler in achieving a high energy storage capacity because of their excellent dielectric properties and good dispersion. In this work, calcined PZT particles were used to prepare PZT/polyvinylidene fluoride (PVDF) composite films. The results showed that composite films of high quality could be obtained even with high contents of submicron PZT particles. The introduction of PZT particles significantly improved the dielectric performance of composite films compared with that of the pristine PVDF film. The discharged energy density of composite films with 10 vol% PZT particles achieved 6.41 J/cm<SUP>3</SUP> at 250 kV/mm. A high efficiency of 87.25% was obtained at 50 kV/mm. These findings confirm the feasibility of PZT particles as inorganic filler in composite films for energy storage applications.</P>

Investigation of temperature sensitivity of actuation performance for piezoelectric fiber composites

Lin, Xiujuan,Chen, Haiyan,Ma, Yupeng,Fisher, John G.,Huang, Shifeng,Zhang, Dou,Cheng, Xin Elsevier 2017 CERAMICS INTERNATIONAL Vol.43 No.13

<P><B>Abstract</B></P> <P>Piezoelectric fiber composites (PFCs) suffer an extremely wide range of temperatures when used in various aerospace structures where temperature effects on the mechanical properties of PFCs are important. In this paper, the actuation performances of PFCs were studied when they were exposed to environmental temperatures from −15°C to 80°C. The results showed that the actuation performance of PFCs was greatly dependent on the environmental temperature. The free strain values and the calculated piezoelectric coefficients d<SUB>33</SUB> and d<SUB>31</SUB> were initially enhanced with the increase of temperature due to the restricted movement of epoxy molecule in the glassy state. The glass transition temperature range of the composite was broadened due to a large number of small pores on the surface of the Pb(Zr,Ti)O<SUB>3</SUB> (PZT) fibers, when the epoxy molecules inside the pores had different transition behaviors compared with those outside the pores. The actuation performance including free strain performance and actuation capability, as well as the piezoelectric coefficients d<SUB>33</SUB> and d<SUB>31</SUB> decreased as the temperature increased above room temperature, since the deformation of epoxy molecules in the viscoelastic state was irreversible.</P>

Recent advances on Pestalotiopsis genus: chemistry, biological activities, structure–activity relationship, and biosynthesis

Peng Jiang,Xiujuan Fu,Hong Niu,Siwei Chen,Feifei Liu,Yu Luo,Dan Zhang,Hui Lei 대한약학회 2023 Archives of Pharmacal Research Vol.46 No.6

Strains of the fungal genus Pestalotiopsis are reported as large promising sources of structurally varied biologically active metabolites. Many bioactive secondary metabolites with diverse structural features have been derived from Pestalotiopsis. Moreover, some of these compounds can potentially be developed into lead compounds. Herein, we have systematically reviewed the chemical constituents and bioactivities of the fungal genus Pestalotiopsis, covering a period ranging from January 2016 to December 2022. As many as 307 compounds, including terpenoids, coumarins, lactones, polyketides, and alkaloids, were isolated during this period. Furthermore, for the benefit of readers, the biosynthesis and potential medicinal value of these new compounds are also discussed in this review. Finally, the perspectives and directions for future research and the potential applications of the new compounds are summarized in various tables.

Synthesis of novel Brønsted–Lewis acidic ionic liquid catalysts and their catalytic activities in acetalization

Yan Wei,Han Xiaoxiang,Chen Keke,Zhang Xiaofang,Kuang Yingying,Tang Xiujuan 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.29 No.-

Ionic liquid catalysts which combine the characters of the Brønsted–Lewis solid acids and the ionic liquidare prepared. The obtained composite materials were well characterized by FT-IR, TGA, 1H NMR, 13CNMR and investigated their performance for acetalization. The acid strength was determined by theHammett method combined with UV–vis spectroscopy. Response surface methodology (RSM) wasapplied to optimize the synthesis of benzaldehyde glycol acetal and the effects of various reactionconditions. A Box–Behnken experimental Design (BBD) was employed to search for the optimal yield. The kinetic study for the acetalization was performed under the optimum operating conditions

Incorporating heuristic information into ant colony optimization for epistasis detection

Junliang Shang,Junying Zhang,Xiujuan Lei,Yuanyuan Zhang,Baodi Chen 한국유전학회 2012 Genes & Genomics Vol.34 No.3

Epistasis has been receiving increasing attention in understanding the mechanism underlying susceptibility to complex diseases. Though many works have been done for epistasis detection, genome-wide association study remains a challenging task: it makes the search space excessively huge while solution quality is excessively demanded. In this study, we introduce an ant colony optimization based algorithm,AntMiner, by incorporating heuristic information into ant-decision rules. The heuristic information is used to direct ants in the search process for improving computational efficiency and solution accuracy. During iterations, chi-squared test is conducted to measure the association between an interaction and the phenotype. At the completion of the iteration process, statistically significant epistatic interactions are ordered and then screened by a post-procedure. Experiments of AntMiner and its comparison with existing algorithms epiMODE, TEAM and AntEpiSeeker are performed on both simulation data sets and real age-related macular degeneration data set, under the criteria of detection power and sensitivity. Results demonstrate that AntMiner is promising for epistasis detection. In terms of detection power, AntMiner performs best among all the other algorithms on all cases regardless of epistasis models and single nucleotide polymorphism size; compared with AntEpiSeeker, AntMiner can obtain better detection power but with less ants and iterations. In terms of sensitivity, AntMiner is better than AntEpiSeeker in detecting epistasis models displaying marginal effects but it has moderate sensitivity on epistasis models displaying no marginal effects. The study may provide clues on heuristics for further epistasis detection. The software package is available online at https://sourceforge.net/projects/antminer/files/.

Heterogeneous amino acid-based tungstophosphoric acids as efficient and recyclable catalysts for selective oxidation of benzyl alcohol

Xiaoxiang Han,Yingying Kuang,Chunhua Xiong,Xiujuan Tang,Qing Chen,Chin-Te Hung,Li-Li Liu,Shang-Bin Liu 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.7

A series of organic-inorganic composite catalysts, prepared by modifying tungstophosphoric acid (TPA; H3PW12O40) with different amino acids such as phenylalanine (Phe), alanine (Ala), and glycine (Gly) were synthesized. The physicochemical and acidic properties of these (MH)xH3−xPW12O40 (M=Phe, Ala, and Gly; x=1-3) composite materials were characterized by a variety of different analytical and spectroscopic techniques, namely TGA, XRD, FTIR, XPS, and NMR, and exploited as heterogeneous catalysts for selective oxidation of benzyl alcohol (BzOH) with hydrogen peroxide (H2O2). Among them, the [PheH]H2PW12O40 catalyst exhibited the best oxidative activity with an excellent BzOH conversion of 99.0% and a desirable benzaldehyde (BzH) selectivity of 99.6%. Further kinetic studies and model analysis by response surface methodology (RSM) revealed that the oxidation of BzOH with H2O2 follows a second-order reaction with an activation energy of 56.7 kJ·mol−1 under optimized experimental variables: BzOH/H2O2 molar ratio=1 : 1.5mol/mol, amount of catalyst=6.1 wt%, reaction time (x3)=3.8 h, and amount of water (x4)=30.2mL.