Dietary Glutamate; Interactions With the Enteric Nervous System

( Guo Du Wang ),( Xi Yu Wang ),( Yun Xia ),( Jackie D Wood ) 대한소화기기능성질환·운동학회 2014 Journal of Neurogastroenterology and Motility (JNM Vol.20 No.1

Background/Aims Digestion of dietary protein elevates intraluminal concentrations of glutamate in the small intestine, some of which gain access to the enteric nervous system (ENS). Glutamate, in the central nervous system (CNS), is an excitatory neurotransmitter. A dogma that glutamatergic neurophysiology in the ENS recapitulates CNS glutamatergic function persists. We reassessed the premise that glutamatergic signaling in the ENS recapitulates its neurotransmitter role in the CNS. Methods Pharmacological analysis of actions of receptor agonists and antagonists in concert with immunohistochemical localization of glutamate transporters and receptors was used. Analysis focused on intracellularly-recorded electrical and synaptic behavior of ENS neurons, on stimulation of mucosal secretion by secretomotor neurons in the submucosal plexus and on muscle contractile behavior mediated by musculomotor neurons in the myenteric plexus. Results Immunoreactivity for glutamate was expressed in ENS neurons. ENS neurons expressed immunoreactivity for the EAAC-1 glutamate transporter. Neither L-glutamate nor glutamatergic receptor agonists had excitatory actions on ENS neurons. Metabotropic glutamatergic receptor agonists did not directly stimulate neurogenic mucosal chloride secretion. Neither L-glutamate nor the metabotropic glutamatergic receptor agonist, aminocyclopentane-1,3-dicarboxylic acid (ACPD), changed the mean amplitude of spontaneously occurring contractions in circular or longitudinal strips of intestinal wall from either guinea pig or human small intestinal preparations. Conclusions Early discoveries, for excitatory glutamatergic neurotransmission in the CNS, inspired enthusiasm that investigation in the ENS would yield discoveries recapitulating the CNS glutamatergic story. We found this not to be the case. (J Neurogastroenterol Motil 2014;20:41-53)

Synthesis and Characterization of Cobalt-Doped WS ₂ Nanorods for Lithium Battery Applications

Wang, Shiquan,Li, Guohua,Du, Guodong,Li, Li,Jiang, Xueya,Feng, Chuanqi,Guo, Zaiping,Kim, Seungjoo Springer 2010 NANOSCALE RESEARCH LETTERS Vol.5 No.8

<P>Cobalt-doped tungsten disulfide nanorods were synthesized by an approach involving exfoliation, intercalation, and the hydrothermal process, using commercial WS<SUB>2</SUB> powder as the precursor and <I>n</I>-butyllithium as the exfoliating reagent. XRD results indicate that the crystal phase of the sample is 2H-WS<SUB>2</SUB>. TEM images show that the sample consists of bamboo-like nanorods with a diameter of around 20 nm and a length of about 200 nm. The Co-doped WS<SUB>2</SUB> nanorods exhibit the reversible capacity of 568 mAh g<SUP>−1</SUP> in a voltage range of 0.01–3.0 V versus Li/Li<SUP>+</SUP>. As an electrode material for the lithium battery, the Co-doped WS<SUB>2</SUB> nanorods show enhanced charge capacity and cycling stability compared with the raw WS<SUB>2</SUB> powder.</P>

Study on the Magnetic Rate Sensitivity and Shear Properties of Magnetorheological Shear Thickening Fluid

Guo-Jun Yu,Shao-Jie Zhu,Cheng-Bin Du,Ling-Yun Wang,Jun-Chi Huang 한국자기학회 2023 Journal of Magnetics Vol.28 No.3

This paper studies magnetic field control and velocity-activated magnetorheological shear thickening fluid (MR-STF). High-concentration STF is composed of nano-sized silica particles suspended in a solvent polyethylene glycol (PEG), and then micron-sized carbonyl iron particles of different mass fractions are added to the STF to manufacture different MR-STF. The rheometer is used to study the viscoelasticity of all four samples. The correlation between dynamic behavior and shear rate, angular frequency, and external magnetic field is studied and discussed. In the lower angular frequency range, the loss modulus is slightly larger than the storage modulus, and MR-STF behaves as a viscoelastic state. After the critical angular frequency, the storage modulus decreases sharply, well below the loss modulus. MR-STF appears in a viscous state and a liquid state. With the start of external field excitation, MR-STF is more inclined to MRF. Finally, the apparent viscosity and shear rate of MR-STF are fitted. The results show that with the increase of magnetic induction strength, the plastic viscosity coefficient of MR fluid increases, the flow characteristic index decreases, and the shear thinning effect becomes more significant.

Gene Microarray Analysis for Porcine Adipose Tissue: Comparison of Gene Expression between Chinese Xiang Pig and Large White

Guo, W.,Wang, S.H.,Cao, H.J.,Xu, K.,Zhang, J.,Du, Z.L.,Lu, W.,Feng, J.D.,Li, N.,Wu, C.H.,Zhang, L. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.1

We created a cDNA microarray representing approximately 3,500 pig genes for functional genomic studies. The array elements were selected from 6,494 cDNA clones identified in a large-scale expressed sequence tag (EST) project. These cDNA clones came from normalized and subtracted porcine adipose tissue cDNA libraries. Sequence similarity searches of the 3,426 ESTs represented on the array using BLASTN identified 2,790 (81.4%) as putative human orthologs, with the remainder consisting of "novel" genes or highly divergent orthologs. We used the gene microarray to profile transcripts expressed by adipose tissue of fatty Chinese Xiang pig (XP) and muscley Large White (LW). Microarray analysis of RNA extracted from adipose tissue of fatty XP and muscley LW identified 81 genes that were differently expressed two fold or more. Transcriptional differences of four of these genes, adipocyte fatty acid binding protein (aP2), stearyl-CoA desaturase (SCD), sterol regulatory element binding transcription factor 1 (SREBF1) and lipoprotein lipase (LPL) were confirmed using SYBR Green quantitative RT-PCR technology. Our results showed that high expression of SCD and SREBF1 may be one of the reasons that larger fat deposits are observed in the XP. In addition, our findings also illustrate the potential power of microarrays for understanding the molecular mechanisms of porcine development, disease resistance, nutrition, fertility and production traits.

Effect of Li on the microstructure and electrical properties of (K_0.17Na_0.83)NbO_3 lead-free piezoceramics

Guo-Zhong Zang,Yan Wang,Xiu-Jie Yi,Juan Du,Zhi-Jun Xu 한국물리학회 2011 Current Applied Physics Vol.11 No.2

Lead-free (K_0.17Na_(0.83-x)Li_x)NbO_3 piezoceramics were synthesized by conventional solid state sintering and the effect of Li on the microstructure and electrical properties was investigated. The experimental results show that 4 mol% Li doping facilitates the grain growth and increases the density of the ceramics. The measurement of dielectric properties reveals that the orthorhombic-tetragonal (T_(O-T)) and tetragonalcubic (T_C) phase transition temperatures change linearly with increasing Li content and the sample with x = 0.06 exhibits the highest T_C of 429 ℃ and lowest T_(O-T) of 181 ℃. Because of the wide apart of T_(O-T) from room temperature, no polymorphic phase structures were obtained and the piezoelectric strain coeffi-cient d_33 and piezoelectric coupling constant k_p varied between low values of 57, 61 pC/N and 0.18, 0.24,respectively with less than 6 mol% Li doping.

Synthesis and Enhanced Photocatalytic Activity of Black Porous Zr-doped TiO2 Monoliths

Jimin Du,Huiming Wang,Huijuan Chen,Menghe Yang,Xiaoling Lu,Hui Guo,Zhanmin Zhang,Tianwei Shang,Shujue Xu,Wenqi Li,Pianpian Wang,Imran Shakir 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.6

Black Porous Zr-doped TiO2 monoliths were successfully synthesized by a combined route including sol–gel method with polystyrene spheres as template followed by calcination at high temperature in the presence of oxygen. As-synthesized samples were then treated in hydrogen atmosphere at 500℃ for 6 h to obtain black Porous Zr-doped TiO2 monoliths. This as-synthesized black porous Zr-doped TiO2 composite showed relatively narrow bandgap compared to the pure anatase phase of TiO2, which may have its origin from the contributions from the Zr impurity and oxygen vacancies. The photocatalytic activity of the black porous Zr-doped TiO2 monolith was examined by carrying out the dye degradation on Rhodamine B under visible irradiation. Our experimental results indicate that black porous 0.9% Zr-doped TiO2 sample exhibits high photocatalytic activity with the photodecomposition of 95.25% under visible irradiation for 120 min.

Experimental Study on Sustained-release 5-Fluorouracil Implantation in Canine Peritoneum and Para-aortic Abdominalis

Wei, Guo,Nie, Ming-Ming,Shen, Xiao-Jun,Xue, Xu-Chao,Ma, Li-Ye,Du, Cheng-Hui,Wang, Shi-Liang,Bi, Jian-Wei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Objective: To observe local and systemic toxicity after sustained-release 5-fluorouracil (5-Fu) implantation in canine peritoneum and para-aortic abdominalis and the changes of drug concentration in the local implanted tissue with time. Methods: 300 mg sustained-release 5-Fu was implanted into canine peritoneum and para-aorta abdominalis. Samples were taken 3, 5, 7 and 10 days after implantation for assessment of changes and systemic reactions. High performance liquid chromatography was applied to detect the drug concentrations of peritoneal tissue at different distances from the implanted site, lymphatic tissue of para-aortic abdominalis, peripheral blood and portal venous blood. Results: 10 days after implantation, the drug concentrations in the peritoneum, lymphatic tissue and portal vein remained relatively high within 5 cm of the implanted site. There appeared inflammatory reaction in the local implanted tissue, but no visible pathological changes such as cell degeneration and necrosis, and systemic reaction like anorexia, nausea, vomiting and fever. Conclusions: Sustained-release 5-Fu implantation in canine peritoneum and para-aortic abdominalis can maintain a relatively high tumour-inhibiting concentration for a longer time in the local implanted area and portal vein, and has mild local and systemic reactions. Besides, it is safe and effective to prevent or treat recurrence of gastrointestinal tumours and liver metastasis.

The antibacterial activity of E. coli bacteriophage lysin lysep3 is enhanced by fusing the Bacillus amyloliquefaciens bacteriophage endolysin binding domain D8 to the C-terminal region

Shuang Wang,Jingmin Gu,Meng Lv,Zhimin Guo,Guangmou Yan,Ling Yu,Chongtao Du,Xin Feng,Wenyu Han,Changjiang Sun,Liancheng Lei 한국미생물학회 2017 The journal of microbiology Vol.55 No.5

Bacteriophage endolysin is one of the most promising antibioticsubstitutes, but in Gram-negative bacteria, the outermembrane prevents the lysin from hydrolyzing peptidoglycansand blocks the development of lysin applications. Theprime strategy for new antibiotic substitutes is allowing lysinto access the peptidoglycan from outside of the bacteria byreformation of the lysin. In this study, the novel Escherichiacoli (E. coli) phage lyase lysep3, which lacks outside-in catalyticability, was fused with the N-terminal region of theBacillus amyloliquefaciens lysin including its cell wall bindingdomain D8 through the best manner of protein fusionbased on the predicted tertiary structure of lysep3-D8 to obtainan engineered lysin that can lyse bacteria from the outside. Our results showed that lysep3-D8 could lyse both Gramnegativeand Gram-positive bacteria, whereas lysep3 and D8have no impact on bacterial growth. The MIC of lysep3-D8on E. coli CVCC1418 is 60 μg/ml; lysep3-D8 can inhibit thegrowth of bacteria up to 12 h at this concentration. The bactericidalspectrum of lysep3-D8 is broad, as it can lyse of allof 14 E. coli strains, 3 P. aeruginosa strains, 1 Acinetobacterbaumannii strain, and 1 Streptococcus strain. Lysep3-D8 hassufficient bactericidal effects on the 14 E. coli strains testedat the concentration of 100 μg/ml. The cell wall binding domainof the engineered lysin can destroy the integrity of theouter membrane of bacteria, thus allowing the catalytic domainto reach its target, peptidoglycan, to lyse the bacteria. Lysep3-D8 can be used as a preservative in fodder to benefitthe health of animals. The method we used here proved to bea successful exploration of the reformation of phage lysin.

Seismic control of high-speed railway bridge using S-shaped steel damping friction bearing

Wei Guo,Yang Wang,Zhipeng Zhai,Qiaodan Du 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.30 No.5

In this study, a new type of isolation bearing is proposed by combining S-shaped steel plate dampers (SSDs) with a spherical steel bearing, and the seismic control effect of a five-span standard high-speed railway bridge is investigated. The advantages of the proposed S-shaped steel damping friction bearing (SSDFB) are that it cannot only lengthen the structural periods, dissipate the seismic energy, but also prevent bridge unseating due to the restraint effectiveness of SSDs in the large relative displacements between the girders and piers. This study first presents a detailed description and working principle of the SSDFB. Then, mechanical modeling of the SSDFB was derived to fundamentally define its cyclic behavior and obtain key mechanical parameters. The numerical model of the SSDFB's critical component SSD was verified by comparing it with the experimental results. After that, parameter studies of the dimensions and number of SSDs, the friction coefficient, and the gap length of the SSDFBs were conducted. Finally, the longitudinal seismic responses of the bridge with SSDFBs were compared with the bridge with spherical bearing and spherical bearing with strengthened shear keys. The results showed that the SSDFB can not only significantly mitigate the shear force responses and residual displacement in bridge substructures but also can effectively reduce girder displacement and prevent bridge unseating, at a cost of inelastic deformation of the SSDs, which is easy to replace. In conclusion, the SSDFB is expected to be a cost-effective option with both multi-stage energy dissipation and restraint capacity, making it particularly suitable for seismic isolation application to high-speed railway bridges.

Characterization of tunnel oxide passivated contact with n-type poly-Si on ptype c-Si wafer substrate

Xueqi Guo,Yuheng Zeng,Zhi Zhang,Yuqing Huang,Mingdun Liao,Qing Yang,Zhixue Wang,Minyong Du,Denggao Guan,Baojie Yan,Jichun Ye 한국물리학회 2019 Current Applied Physics Vol.19 No.7

The junction properties of tunnel silicon oxide (SiOx) passivated contact (TOPCon) with n-type poly-Si on p-type c-Si wafer are characterized using current-voltage (J-V) and capacitance-voltage (C-V) measurements. The dark J-V curves show a standard diode characteristic with a turn-on voltage of ∼0.63 V, indicating a p-n junction is formed. While the C-V curve displays an irregular shape with features of 1) a slow C increase with the decrease of the magnitude of reverse bias voltage, being used to estimate the built-in potential (Vbi), 2) a significant increase at a given positive bias voltage, corresponding to the geometric capacitance crossing the ultrathin SiOx, and 3) a sharp decrease to negative values, resulting from the charge tunneling through the SiOx layer. The C of depleting layer deviates from the normal linear curve in the 1/C2-V plot, which is caused by the diffusion of P dopants from the n-type poly-Si into the p-type c-Si wafer as confirmed by the electrochemical capacitance-voltage measurements. However, the 1/C2+γ-V plots with γ > 0 leads to linear curves with a proper γ and the Vbi can still be estimated. We find that the Vbi is the range of 0.75–0.85 V, increases with the increase of the doping ratio during the poly-Si fabrication process, and correlates with the passivation quality as measured by the reverse saturated current and implied open circuit voltage extracted from transient photoconductivity decay.