Protein Kinase C Mediates the Corticosterone-induced Sensitization of Dorsal Root Ganglion Neurons Innervating the Rat Stomach

( Meng Li ),( Lu Xue ),( Hong-yan Zhu ),( Hongjun Wang ),( Xue Xu ),( Ping-an Zhang ),( Geping Wu ),( Guang-yin Xu ) 대한소화기기능성질환·운동학회 2017 Journal of Neurogastroenterology and Motility (JNM Vol.23 No.3

Background/Aims Gastric hypersensitivity contributes to abdominal pain in patients with functional dyspepsia. Recent studies showed that hormones induced by stress are correlated with visceral hypersensitivity. However, the precise mechanisms underlying gastric hypersensitivity remain largely unknown. The aim of the present study was designed to investigate the roles of corticosterone (CORT) on excitability of dorsal root ganglion (DRG) neurons innervating the stomach. Methods DRG neurons innervating the stomach were labeled by DiI injection into the stomach wall. Patch clamp recordings were employed to examine neural excitability and voltage-gated sodium channel currents. Electromyograph technique was used to determine the responses of neck muscles to gastric distension. Results Incubation of acutely isolated DRG neurons with CORT significantly depolarized action potential threshold and enhanced the number of action potentials induced by current stimulation of the neuron. Under voltage-clamp mode, incubation of CORT enhanced voltage-gated sodium current density of the recorded neurons. Pre-incubation of GF109203X, an inhibitor of protein kinase C, blocked the CORT-induced hyperexcitability and potentiation of sodium currents. However, pre-incubation of H-89, an inhibitor of protein kinase A, did not alter the sodium current density. More importantly, intraperitoneal injection of CORT produced gastric hypersensitivity of healthy rats, which was blocked by pre-administration of GF109203X but not H-89. Conclusions Our data strongly suggest that CORT rapidly enhanced neuronal excitability and sodium channel functions, which is most likely mediated by protein kinase C but not protein kinase A signaling pathway in DRG neurons innervating the stomach, thus underlying the gastric hypersensitivity induced by CORT injection. (J Neurogastroenterol Motil 2017;23:464-476)

Impact of a Glyphosate-Tolerant Soybean Line on the Rhizobacteria, Revealed by Illumina MiSeq

( Gui-hua Lu ),( Yin-ling Zhu ),( Ling-ru Kong ),( Jing Cheng ),( Cheng-yi Tang ),( Xiao-mei Hua ),( Fan-fan Meng ),( Yan-jun Pang ),( Rong-wu Yang ),( Jin-liang Qi ),( Yong-hua Yang ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.3

The global commercial cultivation of transgenic crops, including glyphosate-tolerant soybean, has increased widely in recent decades with potential impact on the environment. The bulk of previous studies showed different results on the effects of the release of transgenic plants on the soil microbial community, especially rhizosphere bacteria. In this study, comparative analyses of the bacterial communities in the rhizosphere soils and surrounding soils were performed between the glyphosate-tolerant soybean line NZL06-698 (or simply N698), containing a glyphosate-insensitive EPSPS gene, and its control cultivar Mengdou12 (or simply MD12), by a 16S ribosomal RNA gene (16S rDNA) amplicon sequencing-based Illumina MiSeq platform. No statistically significant difference was found in the overall alpha diversity of the rhizosphere bacterial communities, although the species richness and evenness of the bacteria increased in the rhizosphere of N698 compared with that of MD12. Some influence on phylogenetic diversity of the rhizosphere bacterial communities was found between N698 and MD12 by beta diversity analysis based on weighted UniFrac distance. Furthermore, the relative abundances of part rhizosphere bacterial phyla and genera, which included some nitrogen-fixing bacteria, were significantly different between N698 and MD12. Our present results indicate some impact of the glyphosate-tolerant soybean line N698 on the phylogenetic diversity of rhizosphere bacterial communities together with a significant difference in the relative abundances of part rhizosphere bacteria at different classification levels as compared with its control cultivar MD12, when a comparative analysis of surrounding soils between N698 and MD12 was used as a systematic contrast study.

Electrospun Polyphenylquinoxaline Ultrafine Non-woven Fibrous Membranes with Excellent Thermal and Alkaline Resistance: Preparation and Characterization

Chen-yu Guo,Lu-meng Yin,Jin-gang Liu,Xin-ke Wang,Na Zhang,Lin Qi,Yan Zhang,Xiao Wu,Xiu-min Zhang 한국섬유공학회 2019 Fibers and polymers Vol.20 No.12

A series of polyphenylquinoxaline (PPQ) ultrafine non-woven fibrous membranes have been first successfullyprepared via the electrospinning procedure with the soluble PPQ solutions as the starting materials. For this purpose, variousorgano-soluble PPQ resins were synthesized via the one-step high temperature polycondensation procedure from thearomatic ether-bridged bis(α-diketone) and bis(o-diamine) monomers. Flexible ether linkages and pendant bulky phenylsubstituents endowed the PPQ resins good solubility in polar aprotic solvents. The high-molecular-weight PPQ resins weredissolved in N-methyl-2-pyrrolidone (NMP) to afford the PPQ electrospinning solution except PPQ-Ia derived from 4,4'-oxydibenzil (ODB) and 3,3'-diaminobenzidine (DAB) due to the limited solubility in the solvent. All the derived PPQultrafine non-woven fibrous membranes maintained good structure integrity after hydrolysis aging either at room temperature(25 oC) for 72 h or at refluxing temperature (100 oC) for 24 h in an aqueous sodium hydroxide (NaOH) solution at a solidcontent of 20 wt%. Comparatively, the polyimide (PI) reference electrospun membrane (PI-ref) derived from 1,2,4,5-pyrromellitic anhydride (PMDA) and 4,4'-oxydianiline (ODA) lost its original structure only after boiling in the same NaOHsolution within 3 h. In addition, the developed PPQ ultrafine non-woven fibrous membranes exhibited good thermal stabilitywith the 5 % weight loss temperatures (T5%) higher than 555.0 oC in nitrogen and glass transition temperatures (Tg) in therange of 248.1-266.1 oC, respectively.

Preparation and Characterization of Electrospun Polyimide Microfibrous Mats with High Whiteness and High Thermal Stability from Organo-soluble Polyimides Containing Rigid-rod Moieties

Chen-yu Guo,Jin-gang Liu,Lu-meng Yin,Meng-ge Huangfu,Yan Zhang,Xiao Wu,Xiu-min Zhang 한국섬유공학회 2018 Fibers and polymers Vol.19 No.8

A series of flexible and tough polyimide (PI) microfibrous mats (PI-1~PI-4) have been prepared via the one-step electrospinning procedure with the organo-soluble PI resins as the starting materials. For this purpose, four PI resins were first synthesized by the chemical imidization reaction from 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and four aromatic diamines containing rigid-rod moieties in their molecular skeletons, respectively. The PI resins derived from 6FDA and aromatic diamines, including PI-1 from 2-(4-aminophenyl)-5-aminobenzimidazole (APBI), PI-2 from 2-(4-aminophenyl)-5-aminobenzoxazole (APBO), PI-3 from 4,4′-diaminobenzanilide (DABA), and PI-4 from 2- chloro-4,4-diaminobenzanilide (Cl-DABA) exhibited good solubility in polar aprotic solvents, such as N-methyl-2- pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). Flexible and tough microfibrous mats were successfully prepared by a one-step electrospinning procedure from the PI/DMAc solution (solid content: 15-20 wt%; absolute viscosity: 8000- 10000 mPa·s). The derived PI mats exhibited good whiteness according to the CIE Lab measurements with W (whiteness) values as high as 94.31, L (lightness) values higher than 94.00, b* (yellowness) values as low as 2.98 and yellow indices (YI) as low as 4.87. In addition, the prepared PI mats exhibited excellent thermal and dimensional stability with the glass transition temperatures (Tg) higher than 345 oC and linear coefficients of thermal expansion (CTE) as low as 27.8×10-6 /K.

The Focused Electrode Ring for Electrohydrodynamic Jet and Printing on Insulated Substrate

Zeshan Abbas,Dazhi Wang,Liangkun Lu,Zhaoliang Du,Xiangyu Zhao,Kuipeng Zhao,Meng Si,Penghe Yin,Xi Zhang,Yan Cui,Junsheng Liang 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.5

Drop-on-demand electrohydrodynamic jet (DoD E-Jet) printing is considered a well-known type of fabrication method contemporary since it can be used to print high-resolution microstructures (< 1 μm) on various insulating substrates. This paper presents a numerical study of DoD E-Jet printing using a novel combination of needle and focused electrode ring to print stable and consistent microdroplets on a Polyethylene terephthalate substrate. Primarily, a phase field method was used to generate a stable cone-jet morphology that can allow the production of high-resolution micron/nano structures on PET substrates. The numerical simulation of cone-jet morphology was performed by COMSOL multiphysics software. Further, the impact of key parameters such as flow rate and dc positive pulse voltage was studied on cone-jet morphology through numerical simulation. Subsequently, optimized operating parameters i.e., f = 5.3 . 10 –15 m 3 s −1 , V n = 1.9 kV and V r = 0.7 kV were achieved by performing a series of numerical experiments. Then, optimized parameters by simulation were directly used to print arrays of stable droplets on PET substrate using the focused electrode ring in different locations by regulating distance 0.2 mm to 1.3 mm between needles to focused electrode ring. The minimum size of stable microdrop was measured 3 μm on PET substrate (thickness = 0.2 mm) using a 50 μm size quartz capillary maintaining a distance of 0.2 mm between combined needle and focused electrode ring. The experimental results proved that the simulation model is useful for printing different microstructures on insulating substrates and creating a promising production path for micro-electro mechanical system and nano-electro mechanical system (MEMS and NEMS).