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Fluorescent Aptamer-polyethylene glycol Functionalized Graphene Oxide Biosensor for Profenofos Detection in Food

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Chemical Research in Chinese Universities 2020年第5期36卷 787-794页

作者： XIONG Jin'en LI Shuang LI Yi CHEN Yingli LIU Yu GAN Junlan JU Jiahui XIAN Yaoling XIONG Xiaohui College of Food Science and L ight Industry Nanjing Tech UniversityNanjing 211816P.R.China

A biosensor based on self-assembled ssDNA(aptamer)and polyethylene glycol functionalized graphene oxide(GO-PEG)has been designed for sensing profenofos in food.The sensor has employed the fluorescence"on/off"switching strategy in a single step iii homogeneous solution.Compared to traditional detection methods,the strategy proposed here is simple,convenient,fast and sensitive.Furthermore,compared with the general aptamer-GO structure,this aptamer-GO-PEG stmcture is in possession of a better detection performance,wliich is largely attributed to the improvement of the biocompatibility and the adjustment of the adsorption capacity of GO by grafting the blocking agent PEG onto the surface of GO.Additionally,the improved biocompatibility of GO shows better stability in salt solutions and physiological solutions,which is more conducive to its practical application in foods.In this project,profenofos had been detected with the proposed strategy,and the limit of detection has been controlled to be 0.21 ng/mL.This aptasensing assay has been applied to detemiining profenofos in(spiked)tap water,cabbage and milk with the recovery values ranging from 93.1% to 108.5%,from 90.8% to 113.2% and from 105.9% to 114.2%,respectively.

关键词： Aptamer Graphene oxide polyethylene glycol Profenofos

Synergistic inhibition of polyethylene glycol and potassium chloride in water-based drilling fluids

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Petroleum Science 2021年第3期18卷 827-838页

作者： Dan-Chao Huang Gang Xie Ni-Yuan Peng Jian-Guo Zou Yao Xu Ming-Yi Deng Wei-Chao Du Yu-Rong Xiao Jin-Jun Huang Ping-Ya Luo State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500SichuanChina College of Chemistry and Chemical Engineering Southwest Petroleum UniversityChengdu 610500SichuanChina College of Chemistry and Chemical Engineering Xi’an Shiyou UniversityXi’an 710056ShanxiChina

Mud shale hydration and swelling are major challenges in the development of water-based drilling fuids(WBDFs).In this work,the inhibition performance and inhibition mechanism of polyethylene glycol(PEG)and potassium chloride(KCl)were investigated by hot rolling recovery tests,linear swell tests,Fourier transform infrared spectroscopy,X-ray difraction,atomic absorption spectrophotometry and X-ray photoelectron spectroscopy.The experimental results show that the combination of PEG and KCl achieved higher recovery and lower linear swelling rate than those obtained by individual PEG or KCl.Compared to the d-spacing of Na-montmorillonite(Na-Mt)with PEG or KCl,the d-spacing of Na-Mt with PEG+KCl was lower,which indicates that KCl and PEG have synergistic inhibition efect.This synergistic efect can replace sodium ions and water molecules from the interlayer space of Na-Mt and decrease the d-spacing of Na-Mt.Based on the above experimental results and analysis,a method for optimizing PEG and KCl concentrations was proposed and further verifed by rheological and hot rolling recovery tests of WBDFs.Hence,the results of this work can provide valuable theoretical guidance for developing other synergistic inhibitors.

关键词： Clay hydration Inhibitor Synergistic inhibition polyethylene glycol Water-based drilling fuids

Electrospun polyethylene glycol/Polyvinyl Alcohol Composite Nanofibrous Membranes as Shape-Stabilized Solid-Solid Phase Change Materials

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Advanced Fiber Materials 2020年第3期2卷 167-177页

作者： Junwen Huang Houyong Yu Somia Yassin Hussain Abdalkarim Jaromir Marek Jiri Militky Yingzhan Li Juming Yao Key Laboratory of Advanced Textile Materials and Manufacturing Technology Zhejiang Provincial Key Laboratory of FiberMaterials and Manufacturing TechnologyZhejiang Sci-Tech UniversityNo.928Avenue 2Xiasha Higher Education ParkHangzhou 310018China Institute for Nanomaterials Advanced Technologies and InnovationsLiberec 46001Czech Republic

In this work,shape-stabilized solid-solid phase change materials(PCMs)were fabricated by simply electrospinning polyethylene glycol(PEG)and polyvinyl alcohol(PVA).Owing to the strong hydrogen bonds and entanglement between those molecular chains of PEG and PVA,PEG was packaged by PVA.The morphological structures,thermal stability and thermal energy storage properties of those fibers were investigated.SEM results showed that those electrospun PVA/PEG composite membranes hold a three-dimensional nonwoven web structure even the content of PEG as high as 70%.The thermal energy storage ability of those composite fibers increased with the increase of the content of PEG.The heat enthalpies of PEG/PVA=7/3 were as high as 78.806 J/g.Moreover,those composite fibers had excellent thermal stability.After 100 heating and cooling cycles,there was almost no obvious change in the melting enthalpy and crystallization enthalpy.Those fibers still maintained good thermal regulation.The simple preparation process,low cost of raw materials and excellent stability endow the PCMs great utilization potentiality in smart textile and energy storage systems.

关键词： Solid-solid PCMs Electrospinning polyethylene glycol

Experimental Research of Gas Hydrate Drilling Fluids Using polyethylene glycol as an Inhibitor

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Journal of China University of Geosciences 2006年第3期17卷 276-282页

作者：张凌蒋国盛涂运中蔡记华窦斌张家铭宁伏龙 Faculty of Engineering China University of Geosciences

Low temperature is the key for maintaining the wellbore stability of the gas hydrate well and for ensuring the safety in the well. In this article, the characteristics of drilling in the permafrost containing gas hydrates are analyzed initially. And later, the relative properties and the inhibitory mechanisms of the polyethylene glycol and the hydrate inhibitor of the drilling fluids ensuring drilling safety are discussed. On the basis of these, the effects of the molecular weight and the content of the polyethylene glycol, and its interaction with the salts on the performances of the four groups of drilling fluids under low temperature are mainly analyzed. The results of these analyses show that for the relative drilling fluid system, the 5% content of polyethylene glycol with a molecular weight of 10 000 combined with 15% NaCl＋5% KCI or 20% NaCl is suitable.

关键词： drilling fluids gas hydrate polyethylene glycol inhibitor.

Preparation and Hydrophilicity of Copolymerization of Chitosan Selectively Grafted by polyethylene glycol

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Journal of Wuhan University of Technology(Materials Science) 2013年第2期28卷 334-338页

作者：李若慧 SHAN Dantong DU Ying Biochemical Engineering College Beijing Union University

Copolymerization of chitosan selectively grafted by polyethylene glycol was prepared. Chitosan was selectively grafted by monomethoxy polyethylene glycol（mPEG-OH）, which contained a hydroxyl group combining with hexamethylene diisocyanate（HDI） to form a novel macromonomer namely monomethoxy polyethylene glycol isocyanate（mPEG-NCO） containing a isocyanate group with higher chemical activity in ethyl glyoxalate solution absolutely without water. The selective grafted copolymerization of Chitosan with mPEG-NCO was conducted under heterogeneous conditions as suspension in dimethylformamide. The hydrophilic copolymers of chitosan were prepared by condensation reaction of isocyanate group on mPEG- NCO with hydroxy groups on chitosan chains because amino groups on chitosan chains were protected by complexion formation with copper ions. The effect of reaction condition on the grafting extents was discussed. Swelling properties of mPEG-g-CS were researched. The graft copolymer mPEG-g-CS was characterized by the infrared spectra. The experimental result showed that the copper ions were very effective to protect amino groups from condensation reaction. The swelling degree in water increases with adding of grafting ratio. The maximum swelling degree was up to above 132% when the grafting ratio was about 270%. The graft copolymer can be soluble partially in pure water.

关键词： chitosan polyethylene glycol selectively graft grafting ratio hydrophilicity swelling properties

Constipation and colonoscopy

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World Journal of Gastrointestinal Endoscopy 2024年第5期16卷 244-249页

作者： Dusan Dj Popovic Branka Filipovic Faculty of Medicine University of BelgradeBelgrade 11000Serbia Department of Gastroenterology and Hepatology Clinic for Internal MedicineUniversity Clinical Hospital Center“Dr.Dragisa Misovic-Dedinje”Belgrade 11000Serbia

Constipation is a significant sociomedical problem,which can be caused by various reasons.In the diagnostic approach to patients with constipation,the following data are usually sufficient:History,complete physical examination(including rectal examination),and additional diagnostic tests.A colonoscopy is not a necessary diagnostic method for all patients with constipation.However,if patients have alarm symptoms/signs,that suggest an organic reason for constipation,a colonoscopy is necessary.The most important alarm symptoms/signs are age>50 years,gastrointestinal bleeding,new-onset constipation,a palpable mass in the abdomen and rectum,weight loss,anemia,inflammatory bowel disease,and family history positive for colorectal cancer.Most endoscopists do not like to deal with patients with constipation.There are two reasons for this,namely the difficulty of endoscopy and the adequacy of preparation.Both are adversely affected by constipation.To improve the quality of colonoscopy in these patients,good examination techniques and often more extensive preparation are necessary.Good colonoscopy technique implies adequate psychological preparation of the patient,careful insertion of the endoscope with minimal insufflation,and early detection and resolution of loops.Bowel preparation for colonoscopy often requires prolonged preparation and sometimes the addition of other laxatives.

关键词： Constipation Functional constipation Colonoscopy Bowel preparation polyethylene glycol

Sodium picosulphate or polyethylene glycol before elective colonoscopy in outpatients?A systematic review and meta-analysis

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World Journal of Gastrointestinal Endoscopy 2018年第12期10卷 422-441页

作者： Rodrigo Silva de Paula Rocha Igor Braga Ribeiro Diogo Turiani Hourneaux de Moura Wanderley Marques Bernardo Maurício Kazuyoshi Minata Flávio Hiroshi Ananias Morita Júlio Cesar Martins Aquino Elisa Ryoka Baba Nelson Tomio Miyajima Eduardo Guimaraes Hourneaux de Moura Gastrointestinal Endoscopy Unit Hospital das Cliicas da Faculdade de Medicina da Universidade de Sao PauloSao Paulo 05403-010Brazil Division of Gastroenterology Hepatology and EndoscopyBrigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115United States

AIM To determine the best option for bowel preparation [sodium picosulphate or polyethylene glycol(PEG)] for elective colonoscopy in adult outpatients.METHODS A systematic review of the literature following the PRISMA guidelines was performed using Medline, Scopus, EMBASE, Central, Cinahl and Lilacs. No restrictions were placed for country, year of publication or language. The last search in the literature was performed on November 20th, 2017. Only randomized clinical trials with full texts published were included. The subjects included were adult outpatients who underwent bowel cleansing for elective colonoscopy. The included studies compared sodium picosulphate with magnesium citrate(SPMC)and PEG for bowel preparation. Exclusion criteria were the inclusion of inpatients or groups with specific conditions, failure to mention patient status(outpatient or inpatient) or dietary restrictions, and permission to have unrestricted diet on the day prior to the exam. Primary outcomes were bowel cleaning success and/or tolerability of colon preparation. Secondary outcomes were adverse events, polyp and adenoma detection rates. Data on intention-totreat were extracted by two independent authors and risk of bias assessed through the Jadad scale. Funnel plots, Egger's test, Higgins' test(I2) and sensitivity analyses were used to assess reporting bias and heterogeneity. The meta-analysis was performed by computing risk difference(RD) using MantelHaenszel(MH) method with fixed-effects(FE) and random-effects(RE) models.Review Manager 5(RevMan 5) version 6.1(The Cochrane Collaboration) was the software chosen to perform the meta-analysis.RESULTS662 records were identified but only 16 trials with 6200 subjects were included for the meta-analysis. High heterogeneity among studies was found and sensitivity analysis was needed and performed to interpret data. In the pooled analysis,SPMC was better for bowel cleaning [MH FE, RD 0.03, IC(0.01, 0.05), P = 0.003, I2= 33%, NNT 34], for tolerability [MH RE, RD 0.08, IC(0.03, 0.13), P = 0.

关键词： Sodium picosulphate polyethylene glycol Bowel cleaning success Tolerability Colonoscopy Randomized clinical trials Meta-analysis

Research Progress of Bowel Preparation for Colonoscopy

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Journal of Biosciences and Medicines 2024年第5期12卷 10-18页

作者： Yongquan Huang Xiaoping Tan Medical College of Yangtze University Jingzhou China Department of Gastroenterology Zhuhai Fifth People&#8217s Hospital Zhuhai China

Colorectal cancer ranks third in the global cancer data in 2020. Colorectal scope is the most effective method to diagnose colorectal diseases such as benign and malignant colorectal tumors. The poor quality of intestinal preparation causes an increased rate of missed diagnosis of colorectal tumors, reduces the rate of cecal intubation for colorectal examination, increases the discomfort, and reduces the compliance of re-examination. Therefore, we should try our best to improve the quality of intestinal preparation. This study reviewed the latest advances related to the preoperative preparation for colonoscopy. Recent research shows that smartphone apps can provide more detailed education and guidance on bowel preparation;Pre-packaged foods are more suitable as a way to eat before colonoscopy. The use of smaller doses, better taste of cathartic agents, and some auxiliary measures, combined with the patient’s situation to provide personalized intestinal preparation measures to improve the quality of intestinal preparation. Starting from the quality of colonoscopy bowel preparation, continuous improvement of patients’ tolerance to bowel preparation, continuous improvement of bowel preparation plan based on individual factors’ needs, and better communication with examined subjects by using existing scientific information technology, may be the hot spot of colonoscopy bowel preparation research in the next few years.

关键词： Colonoscopy Bowel Preparation Preoperative Education Quality of Bowel Preparation polyethylene glycol

Ascorbic acid and low-volume polyethylene glycol for bowel preparation prior to colonoscopy:A meta-analysis

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World Journal of Meta-Analysis 2013年第1期1卷 10-15页

作者： Jonathan D Godfrey Robert E Clark Abhishek Choudhary Imran Ashraf Michelle L Matteson Srinivas R Puli Matthew L Bechtold Division of Gastroenterology University of Missouri Columbia MO 65212 United States OSF MG Gastroenterology University of Illinois Peoria IL 61604 United States

AIM: To evaluate the benefits of low-volume polyethylene glycol(PEG) with ascorbic acid compared to fulldose PEG for colonoscopy preparation. METHODS: MEDLINE, Cochrane Central Register of Controlled Trials and Database of Systematic Reviews, CINAHL, Pub Med, and recent abstracts from major conferences were searched(January 2012). Only randomized-controlled trials on adult subjects comparing lowvolume PEG(2 L) with ascorbic acid vs full-dose PEG(3 or 4 L) were included. Meta-analysis for the efficacy of low-volume PEG with ascorbic acid and full-dose PEG were analyzed by calculating pooled estimates of number of satisfactory bowel preparations as well as adverse patient events(abdominal pain, nausea, vomiting). Separate analyses were performed for each main outcome by using OR with fixed and random effects models. Heterogeneity was assessed by calculating the I2 measure of inconsistency. Rev Man 5.1 was utilized for statistical analysis.RESULTS: The initial search identified 242 articles and trials. Nine studies(n = 2911) met the inclusion criteria and were analyzed for this meta-analysis with mean age range from 53.0 to 59.6 years. All studies were randomized controlled trials on adult patients comparing large-volume PEG solutions(3 or 4 L) with low-volume PEG solutions and ascorbic acid. No statistically significant difference was noted between lowvolume PEG with ascorbic acid and full-dose PEG for number of satisfactory bowel preparations(OR 1.07, 95%CI: 0.86-1.33, P = 0.56). No statistically significant difference was noted between low-volume PEG with ascorbic acid and full-dose PEG for abdominal pain(OR 1.09, 95%CI: 0.81-1.48, P = 0.56), nausea(OR 0.70, 95%CI: 0.49-1.00, P = 0.05), or vomiting(OR 0.99, 95%CI: 0.78-1.26, P = 0.95). No publication bias was noted.CONCLUSION: Low-volume PEG with the addition of ascorbic acid demonstrates no statistically significant difference to full-dose PEG for satisfactory bowel preparation and side-effects.

关键词： polyethylene glycol Ascorbic acid Colonoscopy Meta-analysis Bowel preparation