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Significantly improved oxidation of bio-based furans into furan carboxylic acids using substrate-adapted whole cells

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Journal of Energy Chemistry 2020年第2期29卷 20-26页

作者： Mao Wen xue-ying zhang Min-Hua Zong Ning Li School of Food Science and Engineering South China University of TechnologyGuangzhou 510640GuangdongChina

Furan carboxylic acids are important building blocks in polymer and fine chemical industries. In this work, a simple substrate adaptation strategy was applied to improve the catalytic performances of Comamonas testosteroni SC1588 cells for the synthesis of various furan carboxylic acids. It was found that biocatalytic synthesis of 5-hydroxymethyl-2-furancarboxylic acid(HMFCA) was substantially promoted by adding histidine and increasing cell concentrations. HMFCA was produced in a quantitative yield from200 m M HMF in 24 h. Besides, the HMFCA yields of 71%–81% were achieved with the substrate concentrations up to 250–300 m M. It was firstly found that 4-tert-butylcatechol(TBC), as the stabilizer present in HMF, exerted a significantly detrimental effect on whole-cell catalytic synthesis of HMFCA at high substrate concentrations(more than 130 m M). In addition, a variety of furan carboxylic acids such as2-furoic acid, 5-methyl-2-furancarboxylic acid and 5-methoxymethyl-2-furancarboxylic acid were synthesized with the yields up to 98%.

关键词： 5-hydroxymethylfurfural 5-hydroxymethyl-2-furancarboxylic acid Oxidation Substrate adaptation strategy Whole-cell biocatalysis

Mechanistic and functional extrapolation of SET and MYND domaincontaining protein 2 to pancreatic cancer

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World Journal of Gastroenterology 2022年第29期28卷 3753-3766页

作者： Eid Alshammari ying-xue zhang Zhe Yang Department of Biochemistry Microbiologyand ImmunologyWayne State UniversityDetroitMI 48201United States Department of Biochemistry Microbiologyand ImmunologyWayne State University School of MedicineDetroitMI 48201United States

Pancreatic ductal adenocarcinoma(PDAC)is one of the most lethal neoplasms worldwide and represents the vast majority of pancreatic cancer *** the molecular pathogenesis and the underlying mechanisms involved in the initiation,maintenance,and progression of PDAC is an urgent need,which may lead to the development of novel therapeutic strategies against this deadly ***,we review the role of SET and MYND domaincontaining protein 2(SMYD2)in initiating and maintaining PDAC development through methylating multiple tumor suppressors and oncogenic *** the broad substrate specificity of SMYD2 and its involvement in diverse oncogenic signaling pathways in many other cancers,the mechanistic extrapolation of SMYD2 from these cancers to PDAC may allow for developing new hypotheses about the mechanisms driving PDAC tumor growth and metastasis,supporting a proposition that targeting SMYD2 could be a powerful strategy for the prevention and treatment of PDAC.

关键词： Pancreatic ductal adenocarcinoma Protein lysine methyltransferase Histone/non-histone methylation Oncogenic signaling pathways Methyltransferase inhibitors

Effects of nuclei ambiguus and dorsal motor nuclei of vagus on gastric H^+ and HCO_3^- secretion in rats

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World Journal of Gastroenterology 2006年第20期12卷 3271-3274页

作者： xue-ying zhang Hong-Bin Ai Xi-Yun Cui College of Life Sciences Shandong Normal University Jinan 250014 Shandong Province China

AIM: To determine the effects of electrical stimulation of nucleus ambiguus (NA) and dorsal motor nuclei of vagus (DMV) on gastric acid and bicarbonate secretion in rats. METHODS: NA and DMV in rats were electrically stimulated. Pylorus ligation or esophagus perfusion was used to collect the gastric secretion. The titratable H+ quantum, H+ concentration, HCO3- secretion quantum were measured. RESULTS: Electrical stimulation of NA had no effects on the volume of gastric juice, titratable acidity and acid concentration, but elicited a pronounced increase in the total bicarbonate. However, electrical stimulation of DMV significantly increased the titratable acidity, the volume of gastric juice and the acid concentration. Similarly, electrical stimulation of either NA or DMV decreased the respiratory frequency and sinus bradycardia. CONCLUSION: NA in rats can not control the secretion of gastric acid but the secretion of bicarbonate in gastric juice, while DMV controls the secretion of gastric acid.

关键词： Rat Nucleus ambiguus Dorsal motor nuclei of vagus Gastric acid Gastric bicarbonate

Effect of cyclic hydraulic stimulation on pore structure and methane sorption characteristics of anthracite coal: A case study in the Qinshui Basin, China

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Petroleum Science 2024年第5期21卷 3271-3287页

作者： Rui-Shuai Ma Ji-Yuan zhang Qi-Hong Feng xue-ying zhang Yan-Hui Yang State Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongPR China Shandong Institute of Petroleum and Chemical Technology Dongying257000ShandongPR China PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083PR China PetroChina Huabei Oilfield Company Renqiu062552HebeiPR China

The cyclic hydraulic stimulation(CHS) has proven as a prospective technology for enhancing the permeability of unconventional formations such as coalbeds. However, the effects of CHS on the microstructure and gas sorption behavior of coal remain unclear. In this study, laboratory tests including the nuclear magnetic resonance(NMR), low-temperature nitrogen sorption(LTNS), and methane sorption isotherm measurement were conducted to explore changes in the pore structure and methane sorption characteristics caused by CHS on an anthracite coal from Qinshui Basin, China. The NMR and LTNS tests show that after CHS treatment, meso- and macro-pores tend to be enlarged, whereas micropores with larger sizes and transition-pores may be converted into smaller-sized micro-pores. After the coal samples treated with 1, 3, 5 and 7 hydraulic stimulation cycles, the total specific surface area(TSSA)decreased from 0.636 to 0.538, 0.516, 0.505, and 0.491 m^(2)/g, respectively. Fractal analysis based on the NMR and LTNS results show that the surface fractal dimensions increase with the increase in the number of hydraulic stimulation cycles, while the volume fractal dimensions exhibit an opposite trend to the surface fractal dimensions, indicating that the pore surface roughness and pore structure connectivity are both increased after CHS treatment. Methane sorption isothermal measurements show that both the Langmuir volume and Langmuir pressure decrease significantly with the increase in the number of hydraulic stimulation cycles. The Langmuir volume and the Langmuir pressure decrease from 33.47 cm^(3)/g and 0.205 MPa to 24.18 cm^(3)/g and 0.176 MPa after the coal samples treated with 7 hydraulic stimulation cycles, respectively. The increments of Langmuir volume and Langmuir pressure are positively correlated with the increment of TSSA and negatively correlated with the increments of surface fractal dimensions.

关键词： Coalbed methane Cyclic hydraulic stimulation Pore structure Methane sorption characteristics Fractal analysis

Design of a 200-MHz continuous-wave radio frequency quadrupole accelerator for boron neutron capture therapy

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Nuclear Science and Techniques 2021年第3期32卷 1-10页

作者： Zhi-Chao Gao Liang Lu Chao-Chao Xing Lei Yang Tao He xue-ying zhang Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China The Sino-French Institute for Nuclear Energy and Technology Sun Yat-sen UniversityZhuhai 519000China

A high-intensity continuous-wave(CW) radio frequency quadrupole(RFQ) accelerator is designed for boron neutron capture *** transmission efficiency of a 20-mA proton beam accelerated from 30 keV to 2.5 MeV can reach 98.7% at an operating frequency of 200 *** beam dynamics have a good tolerance to *** comparing the high-frequency parameters of quadrilateral and octagonal RFQ cross sections,the quadrilateral structure of the four-vane cavity is selected owing to its multiple advantages,such as a smaller cross section at the same frequency and easy *** addition,tuners and undercuts are designed to tune the frequency of the cavity and achieve a flat electric field distribution along the *** this paper,the beam dynamic simulation and electromagnetic design are presented in detail.

关键词： RFQ accelerator BNCT Dynamic simulation Electromagnetic design

Aβ28-Induced Specific and Effective Serum Antibodies Against Aβ42

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Chemical Research in Chinese Universities 2010年第6期26卷 974-980页

作者： WANG Jia-peng CUI Li-li HUANG xue-mei zhang ying-jiu Key Laboratory for Molecular Enzymology ＆ Engineering Ministry of Education Jilin University Changchun 130021 P. R. China

Though phase I clinical trial of immunotherapy for Alzheimer＇s disease（AD） with inoculated Aβ42 in humans had been proven to be effective,phase II immunotherapy trial was discontinued in 2002 because a few patients developed significant inflammatory reactions caused by C-terminal domain of Aβ*** aim of the study was to investigate the levels and the abilities of antibodies induced by C-terminal truncated Aβ species to inhibit Aβ42 aggregation and cytotoxity in vitro.46-week-old male BALB/c mice,Aβ42 and Aβ28/Aβ35/Aβ42 with a C-terminal eight-histidine tag（Aβ28H8,Aβ35H8,and Aβ42H8） were applied in the present *** mice were randomly divided into 5 groups（n=8）,control mice immunized with the normal saline,Aβ42-immunized mice and Aβ42H-/Aβ35H-/Aβ28H-immunized *** the serum antibodies were evaluated by measuring their abilities to inhibit Aβ42 aggregation and cytotoxity in *** mouse was vaccinated with purified Aβ peptide emulsified with Freund＇s adjuvant（volume ratio 1：1）.Titers,concentrations and isotypes of serum antibodies against Aβ42 were measured by indirect *** of serum antibodies on Aβ42 aggregation and disassembly of Aβ42 fibrils in vitro were observed by electron *** of serum antibodies on Aβ42 cytotoxicity were determined by MTT assay.Aβ42 or Aβ28 could induce higher anti-Aβ42 antibody titer（1：6400） than Aβ35（1：3200）.Significantly,Aβ28 induced more IgG1 and IgG2b isotype antibodies and less IgG2b isotype antibody than other Aβ species though all the induced serum antibodies could inhibit Aβ42 aggregation or fibrillogenesis,could induce the disassembly of Aβ42 aggregates,and neutralized or inhibited the cytotoxicity of Aβ42 in vitro.C-Terminal truncated Aβ28 could induce the same effective but safer serum antibodies against Aβ42 than full length Aβ42 by eliciting more Th2-type immune responses.

关键词： Alzheimer's disease Amyloid peptide Antibody Epitope Immunization

Heterotopic pregnancy after assisted reproductive techniques with favorable outcome of the intrauterine pregnancy:A case report

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World Journal of Clinical Cases 2023年第3期11卷 669-676页

作者： Ya-Nan Wang Lian-Wen Zheng Lu-Lu Fu ying Xu xue-ying zhang Department of Obstetrics and Gynecology Reproductive Medical CenterThe Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND Heterotopic pregnancy(HP)is a rare condition in which both ectopic and intrauterine pregnancies *** is uncommon after natural conception but has recently received more attention due to the widespread use of assisted reproductive techniques(ART)such as ovulation promotion *** SUMMARY Here,we describe a case of HP that occurred after ART with concurrent tubal and intrauterine singleton *** was treated successfully with surgery to preserve the intrauterine pregnancy,resulting in the birth of a low-weight premature *** case report aims to increase awareness of the possibility of HP during routine first-trimester ultrasound examinations,especially in pregnancies resulting from ART and even if multiple intrauterine pregnancies are *** This case alerts us to the importance of comprehensive data collection during regular *** is important for us to remind ourselves of the possibility of HP in all patients presenting after ART,especially in women with an established and stable intrauterine pregnancy that complain of constant abdominal discomfort and also in women with an unusually raised human chorionic gonadotropin level compared with simplex intrauterine *** will allow symptomatic and timeous treatment of patients with better results.

关键词： Heterotopic pregnancy Assisted reproductive techniques Preterm labor Premature rupture of membranes Case report

Silencing of odorant binding protein gene AlinOBP4 by RNAi induces declining electrophysiological responses of Adelphocoris lineolatus to six semiochemicals

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Insect Science 2017年第5期24卷 789-797页

作者： xue-ying zhang Xiao-Qiang Zhu Shao-Hua Gu Yan-Le Zhou Song-ying Wang Yong-Jun zhang Yu-Yuan Guo State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of AgriculturalSciences Beijing China

Odorant binding proteins （OBPs） are believed to be important for transporting semiochemicals through the aqueous sensillar lymph to the olfactory receptor cells within the insect antennal sensilla. Here, we injected AlinOBP4-siRNA into the conjunctivum between prothorax and mesothorax of the lucerne plant bug, Adelphocoris lineolatus and evaluated the silencing of AlinOBP4 by reverse transcription polymerase chain reaction （RT-PCR） analysis, quantitative real-time PCR （qPCR） test and electroantennogram （EAG） assay. The combination of RT-PCR and qPCR analyses revealed that the levels of mes- senger RNA transcript were significantly reduced ~95% in AlinOBP4-siRNA-treated A. lineolatus males and ~75% in RNAi-treated females within 48 hours. It was found that there are different EAG responses between male and female bugs when the AlinOBP4 gene was silenced by RNAi. The EAGs of A. lineolatus to two plant volatiles, tride- canal and hexyl alcohol, were reduced 9.09% and 79.45% in RNAi-treated males, 62.08% and 62.08% in RNAi-treated females compared to the controls, separately. Antennae of RNAi-treated bugs showed significantly lower electrophysiological responses to four sex pheromone analogs, butyl butanoate, 1-hexyl butyrate, （E）-2-hexenyl butyrate and hexyl hexanoate. The EAG recordings were reduced 35.43%, 35.24%, 39.96% and 78.47% in RNAi-treated males and 64.52%, 18.13%, 36.88% and 49.52% in RNAi-treated females, respectively. The results suggested that AlinOBP4 might play dual-roles in the identifi- cation of plant volatiles and sex pheromones. It was suspected that AlinOBP4 may have different functions in odor perception between male and female A. lineolatus.

关键词： Adelphocoris lineolatus electrophysiological responses odorant bindingprotein AlinOBP4 RNA interference

Expression Characterization and Preparation of Human Amyloid Precursor Protein in Escherichia coli

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Chemical Research in Chinese Universities 2009年第1期25卷 64-68页

作者： XU Guang-wei WANG Jia-peng HUANG xue-mei zhang ying-jiu Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education Jilin University Changehun 130021 P R. China

To analyze whether expressed amyloid precursor protein（APP） existed in hydrophilic（cytoplasmid） or hydrophobic（lipid bilayer） environment in E. coli and to obtain intact APP for study on its function, we investigated the expression characterization and preparation of the three intact isoforms APP770, APP751, and APP695 in E. coll. The results show that these expressed APPs existed both in hydrophilic cytoplasm region as inclusion bodies and hydrophobic membrane region as membrane-bound state in E. coll. APPs in inclusion bodies were purified on an NTA-Ni^2＋ agarose column after dissolving in the urea buffer and APPs in membrane-bound state were obtained by ultracentrifugation. The activity analysis indicates that APP770 and APP751 exhibited strong trypsin-inhibitory activity like the natural ones. These results indicate that E. coli cells can be used as host cells for the expression of human integral membrane protein like APP in either soluble or membrane-bound state unless the interest protein undergone post-translational modification is required.

关键词： Amyloid precursor protein Expression characterization Preparation Membrane Inclusion body