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Increase of β -1, 3-Glucanase and Chitinase Activities in Cotton Callus Cells Treated by Salicylic Acid and Toxin of Verticillium dahliae 被引量:12
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作者 李颖章 郑晓华 +2 位作者 唐海林 朱建伟 杨晶明 《Acta Botanica Sinica》 CSCD 2003年第7期802-808,共7页
The different resistance of cotton (Gossypium hirsutum L.) cultivars to crude toxin of Verticillium dah/iae(VD) was correlated with the activities of chitinase and β-1, 3-glucanase in callus cells. The activities of ... The different resistance of cotton (Gossypium hirsutum L.) cultivars to crude toxin of Verticillium dah/iae(VD) was correlated with the activities of chitinase and β-1, 3-glucanase in callus cells. The activities of chitinase and β-1, 3-glucanase in the callus cells treated with the VD-toxin were increased to the higher level at earlier time point in resistant cultivars than these in the susceptible cultivars. Exogenous salicylic acid (SA) induced the accumulation of chitinase and β -1,3-glucanase, which resulted in the resistance of callus cells to the VD. toxin. Western blot using a polyclonal antibody against β -1,3-glucanase identified 28 kD protein that was induced by VD-toxin, SA, or VD-toxin plus SA. 展开更多
关键词 Gossypium hirsutum toxin of Verticillium dahliae salicylic acid CHITINASE Β-1 3-GLUCANASE
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2-氯酮与Meldrum’s acid的反应研究 被引量:2
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作者 丛志奇 尹炳柱 +2 位作者 金龙一 陈铁 李国雷 《化学试剂》 CAS CSCD 北大核心 2003年第6期321-322,366,共3页
探讨了2-氯(?)酮与Meldrum’s acid在不同条件下的反应结果,合成了化合物2-氧代-3-羧基-1-氧杂薁。并用1HN- MR,13CNMR和IR表征了其结构。
关键词 2-氯Zhuo酮 Meldrum′s acid 亲核试剂 2-氧代-3-羧基-1-氧杂薁 药物中间体
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Δ4-3-oxosteroid-5β-reductase deficiency: Responses to oral bile acid therapy and long-term outcomes 被引量:7
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作者 Mei-Hong Zhang Kenneth DR Setchell +3 位作者 Jing Zhao Jing-Yu Gong Yi Lu Jian-She Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第7期859-869,共11页
BACKGROUND Disorders of primary bile acid synthesis may be life-threatening if undiagnosed,or not treated with primary bile acid replacement therapy. To date, there are few reports on the management and follow-up of p... BACKGROUND Disorders of primary bile acid synthesis may be life-threatening if undiagnosed,or not treated with primary bile acid replacement therapy. To date, there are few reports on the management and follow-up of patients with Δ4-3-oxosteroid 5β-reductase(AKR1 D1) deficiency. We hypothesized that a retrospective analysis of the responses to oral bile acid replacement therapy with chenodeoxycholic acid(CDCA) in patients with this bile acid synthesis disorder will increase our understanding of the disease progression and permit evaluation of this treatment regimen as an alternative to the Food and Drug Administration(FDA) approved drug cholic acid, which is currently unavailable in China.AIM To evaluate the therapeutic responses of patients with AKR1 D1 deficiency to oral bile acid therapy, specifically CDCA.METHODS Twelve patients with AKR1 D1 deficiency, confirmed by fast atom bombardment ionization-mass spectrometry analysis of urine and by gene sequencing for mutations in AKR1 D1, were treated with differing doses of CDCA or ursodeoxycholic acid(UDCA). The clinical and biochemical responses to therapy were monitored over a period ranging 0.5-6.4 years. Dose adjustment, to optimize the therapeutic dose, was based on changes in serum biochemistry parameters,notably liver function tests, and suppression of the urinary levels of atypical hepatotoxic 3-oxo-Δ4-bile acids measured by mass spectrometry.RESULTS Physical examination, serum biochemistry parameters, and sonographic findings improved in all 12 patients during bile acid therapy, except one who underwent liver transplantation. Urine bile acid analysis confirmed a significant reduction in atypical hepatotoxic 3-oxo-Δ4 bile acids concomitant with clinical and biochemical improvements in those patients treated with CDCA. UDCA was ineffective in down-regulating endogenous bile acid synthesis as evidenced from the inability to suppress the urinary excretion of atypical 3-oxo-Δ4-bile acids. The dose of CDCA required for optimal clinical and biochemical responses varied from 5.5-10 mg/kg per day among patients based on maximum suppression of the atypical bile acids and improvement in serum biochemistry parameters, and careful titration of the dose was necessary to avoid side effects from CDCA.CONCLUSION The primary bile acid CDCA is effective in treating AKR1 D1 deficiency but the therapeutic dose requires individualized optimization. UDCA is not recommended for long-term management. 展开更多
关键词 Δ4-3-oxosteroid--reductase DEFICIENCY Mass SPECTROMETRY BILE acid synthesis DISORDER Chenodeoxycholic acid Ursodeoxycholic acid
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Biocatalytic synthesis of (R)-(-)-mandelic acid from racemic mandelonitrile by a newly isolated nitrilase-producer Alcaligenes sp. ECU0401 被引量:12
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作者 Yu Cai He Jian He Xu +2 位作者 Yi Xu Li Ming Ouyang Jiang Pan 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期677-680,共4页
By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mand... By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mandelonitrile into (R)-(?)-mandelic acid, with an enantiomeric excess of >99.9%. 展开更多
关键词 Mandelonitrile NITRILASE (R)-()-Mandelic acid SCREENING Alcaligenes sp. ECU0401
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Identification and Mutagenesis of a New Isolated Strain Bacillus sp.B26 for Producing (R)-α-Hydroxyphenylacetic Acid 被引量:3
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作者 CHEN Bingmei XU Xiaoping +2 位作者 HOU Zhiguo LI Zhongqin RUAN Wenbing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期636-643,共8页
A bacterium strain B26 capable of producing(R)-α-hydroxyphenylacetic acid [(R)-HPA](yield,47.5%;enantiomeric excess,99.1%) from phenylglyoxylic acid(PGA) with high optical purity was isolated and identified as Bacill... A bacterium strain B26 capable of producing(R)-α-hydroxyphenylacetic acid [(R)-HPA](yield,47.5%;enantiomeric excess,99.1%) from phenylglyoxylic acid(PGA) with high optical purity was isolated and identified as Bacillus sp.B26 by 16S rDNA(ribosomal DNA) sequencing.Phylogenic analysis showed that the strain was most similar to Bacillus sp.enrichment culture clone SYW5(FJ601635.1) and Bacillus cereus strain FM-4(EU794727.1).Efforts were made to further improve HPA-production and PGA-tolerance by UV irradiation and UV-LiCl cooperative mutagenesis.Among viable mutants,B.sp.UV-38 and B.sp.ULi-11 exhibited better productivities than the wild type.Comparisons of HPA production and time course among wild strain and two mutants showed that B.sp.ULi-11 was more competent than B.sp.UV-38.HPA production was increased by 39.1% with B.sp.ULi-11(yield,65.4%) compared to that with B.sp.B26(yield,47.0%) when cultured in fermentation broth(pH 7.2) at 32℃ with an agitation speed of 180 r·min-1 and PGA final concentration of 15 mmol·L-1 for 25 h. 展开更多
关键词 (R)-α-hydroxyphenylacetic acid BIOTRANSFORMATION phylogenetic analysis Bacillus phenylglyoxylic acid UV mutagenesis
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Transgenic Pigs Carrying a Synthesized Fatty Acid Desaturase Gene Yield High Level of ω-3 PUFAs 被引量:7
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作者 REN Hong-yan ZHENG Xin-min +1 位作者 CHEN Hong-xing LI Kui 《Agricultural Sciences in China》 CAS CSCD 2011年第10期1603-1608,共6页
Polyunsaturated fatty acids (PUFAs) are essential for normal growth in mammals, especially the ω-3 PUFAs, which play important roles in preventing several life-threatening diseases, such as coronary heart disease a... Polyunsaturated fatty acids (PUFAs) are essential for normal growth in mammals, especially the ω-3 PUFAs, which play important roles in preventing several life-threatening diseases, such as coronary heart disease and diabetes. In this study, we aimed to investigate whether the sFat-1 gene from Caenorhabditis briggsae could be functionally expressed in transgenic pigs, and whether the transgenic could synthesize high quality ω-3 PUFAs endogenously. In this study, a gene construct consisting of CMV promoter and 1.9 kb cDNA of ω-3 fatty acid desaturase gene (sFat-1) from C. briggsae was injected into the male pronucleus of pig embryos by microinjection. The piglets were screened for the transgene by PCR, Southern blot and reverse transcription-PCR analysis. Pigs that give positive results were mated with wild-type pigs to produce the next generation and the transmission of transgene was examined by PCR analysis. Fatty acids compositions of various tissues in the transgenic pigs were then analyzed by gas chromatograph. A total of 878 embryos were transferred into 42 recipients, among which 29 successfully got pregnant and gave birth to a total of 162 piglets, and 8 of them were identified to be transgenic. Fatty acid compositions in the transgenic pigs were altered, and the levels of ω-6:ω-3 ratios were decreased from 14.53 in the control to 2.62 in Fat-1 transgenic pigs. A number of primary sFat-1-transgenic pigs were bred in this study, which lays the foundation for cultivation of new varieties of transgenic pigs. 展开更多
关键词 transgenic pigs sFat-1 gene ω-3 polyunsaturated fatty acids MICROINJECTION
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An efficient route towards R-2-phenoxypropionic acid synthesis for biotransformative production of R-2-(4-hydroxyphenoxy)propionic acid 被引量:3
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作者 Haiyan Zhou Yizuo Li +4 位作者 Rui Jiang Xianlin Wang Yuanshan Wang Yaping Xue Yuguo Zheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期315-323,共9页
R2(4hydroxyphenoxy)propionic acid(RHPPA)is a key intermediate for the synthesis of classic herbicides with high selectivity against grassy weed.The main route for RHPPA biosynthesis is to hydroxylate the substrate R2p... R2(4hydroxyphenoxy)propionic acid(RHPPA)is a key intermediate for the synthesis of classic herbicides with high selectivity against grassy weed.The main route for RHPPA biosynthesis is to hydroxylate the substrate R2phenoxypropionic acid(RPPA)at C4 position with microbes.In order to provide sufficient RPPA for the industrial production of RHPPA,an effective RPPA synthesis method was established and optimized in this work.The synthesis process mainly consisted of two steps:(1)synthesis of S2chloropropionic acid from Lalanine via diazotization and chlorination reactions;and(2)synthesis of RPPA from S2chloropropionic acid and phenol via etherification reaction.The optimal reaction conditions were as follows:HCl:NaNO_(2):KI:LAla=2.0:1.2:0.7:1.0(in molar),125℃reflux for 1.5 h,with KI as catalyst,and KI:S2chloropropionic acid:phenol=0.075:1.2:1.0(in molar).Under these conditions,an improved molar conversion rate(74.9%,calculated in phenol)was achieved.After extraction using anionic exchange resin Amberlite IRA400(CI),RPPA product with a purity of 95.08%was obtained.The purified RPPA was identified and evaluated in the application of the biotransformative production of RHPPA.The results indicated that the synthesized RPPA supported the RHPPA biosynthesis with a comparable yield as that of the standard RPPA.The RPPA synthesis method provided herein exhibited the advantages of low price and easy availability of raw materials,less toxicity of reagents,simple manipulations,and low equipment/instrument requirements. 展开更多
关键词 R-2-phenoxypropionic acid R-2-(4-hydroxyphenoxy)propionic acid BIOSYNTHESIS S-2-chloropropionic acid
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Kinetics of Asymmetric Reduction of Phenylglyoxylic Acid to R-(-)-Mandelic Acid by Saccharomyces Cerevisiae FD11b 被引量:9
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作者 肖美添 黄雅燕 +1 位作者 孟春 郭养浩 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第1期73-80,共8页
The kinetics of asymmetric production of R-(-)-mandelic acid (R-MA) from phenylglyoxylic acid (PGA) catalyzed by Saccharomyces cerevisiae sp. strain FD11b was studied by fed-batch cultures. The concentrations of... The kinetics of asymmetric production of R-(-)-mandelic acid (R-MA) from phenylglyoxylic acid (PGA) catalyzed by Saccharomyces cerevisiae sp. strain FD11b was studied by fed-batch cultures. The concentrations of glucose and PGA were controlled respectively with a dual feeding system. When the electron donor glucose was supplied at the rate of 0.0833mmol·gdw^-1·h^-1, the specific production rate (qp) and the enantiomeric excess of R-MA reached the maximum 0.353mmol·gdw^-1·h^-1 and 97.1%, respectively. The apparent reduction activity of yeast FD 11 b was obviously affected by both substrate PGA and product MA. The qp value reached the maximum 0.36-0.38mmol·gdw^-1·h^-1 when the PGA concentration was controlled between 25 and 35mmol·L^-1. The obvious substrate inhibition of bioconversion was observed at the PGA concentrations higher than 40mmol·L^-1. The accumulation of product MA also caused a severe feed-back inhibition for its production when the product concentration was above 60mmol·L^-1. The kinetic model with the inhibition effect of both substrate and product was simulated by a computer-based least-square arithrnatic. The established kinetic model was in good agreement with the experimental data. 展开更多
关键词 Saccharomyces cerevisiae asymmetric reduction R---mandelic acid substrate inhibition product inhibi- tion kinetic model
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Estrogen affects neuropathic pain through upregulating N-methyl-D-aspartate acid receptor 1 expression in the dorsal root ganglion of rats 被引量:8
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作者 Chao Deng Ya-juan Gu +1 位作者 Hong Zhang Jun Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第3期464-469,共6页
Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in t... Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D(-)-2-amino-5-phosphonopentanoic acid(AP-5),or both once daily for 15 days.Compared with injured drug na?ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity(as assessed by immunohistochemistry) and protein(as determined by western blot assay) in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia. 展开更多
关键词 nerve regeneration peripheral nerve injury ESTROGEN 17Β-ESTRADIOL N-rnethyl-D-aspartic acid receptor 1 pain sciatic nerve chronic constriction injury neuropathic pain D(--2-amino-5-phosphonopentanoic acid dorsal root ganglion spinal cord IMMUNOREACTIVITY western blot assay neural regeneration
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Crystal Structure and Magnetic Property of 2-(Imidazo[1,2-α]pyri-din-2-yl)- 2-oxoacetic Acid and Its Perchlorate
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作者 沈忱 张一曼 雍国平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期240-244,I0002,共6页
We herein report two crystals based on 2-(imidazo[1,2-a]pyridin-2-yl)-2-oxoacetic acid rad- ical and its perchlorate, and investigate the relationship between magnetic properties and crystal stacking structures or s... We herein report two crystals based on 2-(imidazo[1,2-a]pyridin-2-yl)-2-oxoacetic acid rad- ical and its perchlorate, and investigate the relationship between magnetic properties and crystal stacking structures or supramolecular interactions. 2-(imidazo[1,2-a]pyridin-2-yl)- 2-oxoaeetic acid radical in two crystals mainly exist as diamagnetic dimer formed via short atomic contacts or supramolecular interactions (hydrogen bonds, anion-Tr or lone- pair-~r interactions), leading to low magnetic susceptibilities. 2-(imidazo[1,2-a]pyridin-2-yl)- 2-oxoaeetic acid radical crystal exhibits quasi-one-dimensional columnar stacking chain and weak antiferromagnetism. However, its perchlorate crystal possesses one-dimensional double- stranded chain structure assembled through double hydrogen bonds and anion-To interactions, and reveals weak ferromagnetism. 展开更多
关键词 2-(Imidazo[1 2-α]pyridin-2-yl)-2-oxoacetic acid radical Crystallographic struc-ture Magnetic properties Organic compound
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Usefulness of ω-3 fatty acid supplementation in addition to mesalazine in maintaining remission in pediatric Crohn's disease: A double-blind, randomized, placebo-controlled study 被引量:4
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作者 C Romano S Cucchiara +3 位作者 A Barabino V Annese C Sferlazzas SIGENP Italian Study Group of Pediatric Inflammatory Bowel Diseases 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第45期7118-7121,共4页
AIM: To assess the value of long-chain w-3 fatty acids (FAs) supplementation in addition to amino-salicylic-acid (5-ASA) in pediatric patients with Crohn's disease (CD). METHODS: Thirty-eight patients (20 ma... AIM: To assess the value of long-chain w-3 fatty acids (FAs) supplementation in addition to amino-salicylic-acid (5-ASA) in pediatric patients with Crohn's disease (CD). METHODS: Thirty-eight patients (20 males and 18 females, mean age 10.13 years, range 5-16 years) with CD in remission were randomized into two groups and treated for 12 too. Group Ⅰ (18 patients) received 5-ASA (50 mg/kg/d)+w-3 FAs as triglycerides in gastroresistant capsules, 3 g/d (eicosapentanoic acid, EPA, 400 mg/g, docosahexaenoic acid, DHA, 200 mg/g). Group Ⅱ (20 patients) received 5-ASA (50 mg/kg/d)+olive oil placebo capsules. Patients were evaluated for fatty acid incorporation in red blood cell membranes by gas chromatography at baseline 6 and 12 mo after the treatment. RESULTS: The number of patients who relapsed at 1 year was significantly lower in group I than in group Ⅱ (P〈0.001). Patients in group I had a significant increase in the incorporation of EPA and DHA (P〈0.001) and a decrease in the presence of arachidonic acids. CONCLUSION: Enteric-coated w-3 FAs in addition to treatment with 5-ASA are effective in maintaining remission of pediatric CD. 展开更多
关键词 Crohn's disease ω-3 fatty acids Remission maintenance Treatment
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Effects of ω-3 fatty acids on toll-like receptor 4 and nuclear factor-κB p56 in lungs of rats with severe acute pancreatitis 被引量:12
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作者 Bin Wang Xiao-Wei Wu +4 位作者 Mei-Xia Guo Min-Li Li Xiao-Bing Xu Xin-Xin Jin Xiao-Hua Zhang 《World Journal of Gastroenterology》 SCIE CAS 2016年第44期9784-9793,共10页
AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 5... AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 56 Sprague-Dawley rats were randomly divided into 4 groups: control group, SAP-saline group, SAP-soybean oil group and SAP-ω-3FA group. SAP was induced by the retrograde infusion of sodium taurocholate into the pancreatic duct. The expression of TLR4 and NF-κBp56 in the lungs was evaluated by immunohistochemistry and Western blot analysis. The levels of inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha in the lungs were measured by enzyme-linked immunosorbent assay. RESULTS The expression of TLR4 and NF-κBp56 in lungs and of inflammatory cytokines in serum significantly increased in the SAP group compared with the control group(P < 0.05), but was significantly decreased in the ω-3FA group compared with the soybean oil group at 12 and 24 h(P < 0.05).CONCLUSION During the initial stage of SAP, ω-3FA can efficiently lower the inflammatory response and reduce lung injury by triggering the TLR4/NF-κBp56 signal pathway. 展开更多
关键词 Severe acute pancreatitis ω-3 fatty acids Lung injury Toll-like receptor 4 Nuclear factor-κB p56 CYTOKINE
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A New Luminescent Cd(Ⅱ) Coordination Polymer Constructed with 2-(Carboxymethoxy) benzoic Acid 被引量:5
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作者 王秀艳 李冠霆 +3 位作者 孙迪雅 张莹 刘东雪 徐占林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1939-1944,1845,共7页
In this work, we synthesized a new Cd(Ⅱ) coordination polymer, [Cd(L)(cmb)H;O]· H;O(1), by using mixed 2-(carboxymethoxy)benzoic acid(H2 cmb) and typical chelating N-donor ligands 2-(2-fluoro-6-fluoro... In this work, we synthesized a new Cd(Ⅱ) coordination polymer, [Cd(L)(cmb)H;O]· H;O(1), by using mixed 2-(carboxymethoxy)benzoic acid(H2 cmb) and typical chelating N-donor ligands 2-(2-fluoro-6-fluorophenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline ligand(L). 1 crystallizes in monoclinic, space group P21/c with a = 17.6150(8), b = 9.7811(4), c = 18.1603(8) ?, β = 118.9150(10)o, V = 2738.9(2) ?;, Z = 4, C28 H20 CdF2 N4 O7, Mr = 674.88, Dc = 1.637 g/cm3, F(000) = 1352, μ(Mo Ka) = 0.865 mm–1, R = 0.0643 and w R = 0.1976. In 1, the cmb2– anions link neighboring Cd(Ⅱ) atoms in a bis-chelating mode, yielding a one-dimensional chain structure along the b axis. The L ligands are attached on one side of the chain through chelating the Cd(Ⅱ) atoms, and are stacked with those of an adjacent chain through π-π interactions to generate a one-dimensional double-chain structure. Furthermore, the one-dimensional double-chains are stacked by C–H???π interactions between the carbon atom of L ligand and the benzene ring of cmb2–ligand to give a layer structure. Moreover, the solid state luminescent property of 1 was also investigated at room temperature. 展开更多
关键词 crystal structure coordination polymer 2-(carboxymethoxy)benzoic acid
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Extraction Equilibria of Trimellitic and [ 1,1′-Biphenyl]-2,2′-dicarboxylic Acid with 1-Octanol, 50%TBP, and 10%TRPO in Kerosene 被引量:2
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作者 周智勇 秦炜 戴猷元 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期867-870,共4页
To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equil... To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate (TBP) in kerosene, and 10% trialkylphosphine oxide (TRPO) in kerosene. The results showed that the degree of extraction of [1,1′-biphenyl]-2,2′-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1′-biphenyl]-2,2′-dicarboxylic acid from the mixture of trimellitic acid and [1,1′-biphenyl]-2,2′-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [ 1, 1′-biphenyl]-2,2′-dicarboxylic to trimellitic acid depends on the stoichiometric ratio. 展开更多
关键词 trimellitic acid [1 1′-biphenyl]-2 2′-dicarboxylic acid extraction equilibrium 1-octanol TBP and TRPO
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Synthesis, Crystal Structure and DNA-Binding Property of a Mn(Ⅱ) Complex Based on 5-(Tri-fluoromethyl)pyridine-2-carboxylic Acid 被引量:4
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作者 WANG Jia-Kai LI Bing +2 位作者 WU Huan-Ping TIAN Xiao-Yan MA Xiao-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第8期1349-1355,共7页
A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ... A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc. 展开更多
关键词 5-(trifluoromethyl)pyridine-2-carboxylic acid crystal structure DNA fluorescence SPECTRA
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1D Lanthanide Coordination Polymers Based on 3-(Pyridin-4-yl)benzoic Acid: Syntheses, Structures and Luminescent Properties 被引量:4
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作者 肖雪英 韦永勤 +1 位作者 郑文旭 吴克深 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1543-1550,共8页
ABSTRACT Four novel 1D lanthanide coordination polymers with formula [Ln(3,4-pybz)3(HzO)2. H2O]n (Ln = 1 Sm; 2 Eu; 3 Tb; 4 Dy, 3,4-Hpybz = 3-(pyridin-4-yl)benzoic acid) have been synthesized by hydrothermal re... ABSTRACT Four novel 1D lanthanide coordination polymers with formula [Ln(3,4-pybz)3(HzO)2. H2O]n (Ln = 1 Sm; 2 Eu; 3 Tb; 4 Dy, 3,4-Hpybz = 3-(pyridin-4-yl)benzoic acid) have been synthesized by hydrothermal reactions of lanthanide oxide and 3-(pyridine-4-yl) benzoic acid. Single-crystal X-ray diffraction shows that the four compounds are isostructural. They all crystallize in a monoelinic system, space group P1^-. They have a doubly carboxylate-bridged infinite-chain structure with alternating Ln-(carboxylate)2-Ln linkages and one chelating carboxylate group on each metal center. The Ln ion also combines to two water molecules to form an eight-coordinate square antiprismatic geometry. The pyridine nitrogen atoms of the ligand do not coordinate to the metal centers but direct the formation of a 3D network through hydrogen bonding with coordinated water molecules. The photoluminescent properties of 2 and 3 have been also studied. 展开更多
关键词 lanthanide coordination polymer 3-(pyridine-4-yl) benzoic acid HYDROGEN-BONDING photoluminescence
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Luteolin prevents uric acid-induced pancreatic β-cell dysfunction 被引量:3
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作者 Ying Ding Xuhui Shi +5 位作者 Xuanyu Shuai Yuemei Xu Yun Liu Xiubin Liang Dong Wei Dongming Su 《The Journal of Biomedical Research》 CAS 2014年第4期292-298,共7页
Elevated uric acid causes direct injury to pancreatic β-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced β-cell dysfunction. We first evaluated the effect of ... Elevated uric acid causes direct injury to pancreatic β-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced β-cell dysfunction. We first evaluated the effect of luteolin on nitric oxide (NO) formation in uric acid-stimulated Min6 cells using the Griess method. Next, we performed transient transfection and reporter assays to measure transcriptional activity of nuclear factor (NF)-κB. Western blotting assays were also performed to assess the effect of luteolin on the expression of MafA and inducible NO synthase (iNOS) in uric acid-treated cells. Finally, we evaluated the effect of luteolin on uric acidinduced inhibition of glucose-stimulated insulin secretion (GSIS) in Min6 cells and freshly isolated mouse pancreatic islets. We found that luteolin significantly inhibited uric acid-induced NO production, which was well correlated with reduced expression of iNOS mRNA and protein. Furthermore, decreased activity of NF-κB was implicated in inhibition by luteolin of increased iNOS expression induced by uric acid. Besides, luteolin significantly increased MafA expression in Min6 cells exposed to uric acid, which was reversed by overexpression of iNOS. Moreover, luteolin prevented uric acidinduced inhibition of GSIS in both Min6 cells and mouse islets. In conclusion, luteolin protects pancreatic β-cells from uric acid-induced dysfunction and may confer benefit on the protection of pancreatic β-cells in hyperuricemiaassociated diabetes. 展开更多
关键词 LUTEOLIN uric acid nitric oxide nuclear factor (NF)-κB MAFA
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18β-glycyrrhetinic acid inhibits proliferation of gastric cancer cells through regulating the miR-345-5p/TGM2 signaling pathway 被引量:3
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作者 Xia Li Xiao-Ling Ma +8 位作者 Yi Nan Yu-Hua Du Yi Yang Dou-Dou Lu Jun-Fei Zhang Yan Chen Lei Zhang Yang Niu Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第23期3622-3644,共23页
BACKGROUND Gastric cancer(GC)is a common gastrointestinal malignancy worldwide.Based on cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is ... BACKGROUND Gastric cancer(GC)is a common gastrointestinal malignancy worldwide.Based on cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is important to find effective drug treatment targets.AIM To explore the molecular mechanism of 18β-glycyrrhetinic acid(18β-GRA)regulating the miR-345-5p/TGM2 signaling pathway to inhibit the proliferation of GC cells.METHODS CCK-8 assay was used to determine the effect of 18β-GRA on the survival rate of GES-1 cells and AGS and HGC-27 cells.Cell cycle and apoptosis were detected by flow cytometry,cell migration was detected by a wound healing assay,the effect of 18β-GRA on subcutaneous tumor growth in BALB/c nude mice was investigated,and the cell autophagy level was determined by MDC staining.TMT proteomic analysis was used to detect the differentially expressed autophagy-related proteins in GC cells after 18β-GRA intervention,and then the protein-protein interaction was predicted using STRING(https://string-db.org/).MicroRNAs(miRNAs)transcriptome analysis was used to detect the miRNA differential expression profile,and use miRBase(https://www.mirbase/)and TargetScan(https://www.targetscan.org/)to predict the miRNA and complementary binding sites.Quantitative real-time polymerase chain reaction was used to detect the expression level of miRNA in 18β-GRA treated cells,and western blot was used to detect the expression of autophagy related proteins.Finally,the effect of miR-345-5p on GC cells was verified by mir-345-5p overexpression.RESULTS 18β-GRA could inhibit GC cells viability,promote cell apoptosis,block cell cycle,reduce cell wound healing ability,and inhibit the GC cells growth in vivo.MDC staining results showed that 18β-GRA could promote autophagy in GC cells.By TMT proteomic analysis and miRNAs transcriptome analysis,it was concluded that 18β-GRA could down-regulate TGM2 expression and up-regulate miR-345-5p expression in GC cells.Subsequently,we verified that TGM2 is the target of miR-345-5p,and that overexpression of miR-345-5p significantly inhibited the protein expression level of TGM2.Western blot showed that the expression of autophagy-related proteins of TGM2 and p62 was significantly reduced,and LC3II,ULK1 and AMPK expression was significantly increased in GC cells treated with 18β-GRA.Overexpression of miR-345-5p not only inhibited the expression of TGM2,but also inhibited the proliferation of GC cells by promoting cell apoptosis and arresting cell cycle.CONCLUSION 18β-GRA inhibits the proliferation of GC cells and promotes autophagy by regulating the miR-345-5p/TGM2 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid Gastric cancer MiR-345-5p TGM2 PROLIFERATION AUTOPHAGY
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Synthesis and Crystal Structure of a New Copper(II) Complex with 4-Cyanobenzoic Acid 被引量:6
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作者 LI Yan WU A-Qing +3 位作者 ZHENG Fa-Kun GUO Guo-Cong LU Can-Zhong HUANG Jin-Shun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1281-1285,共5页
A new Cu(Ⅱ) complex [Cu(4-cba)(1,10-phen)(H2O)2](NO3) (4-Hcba = 4-cyanobenzoic acid) has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characteriz... A new Cu(Ⅱ) complex [Cu(4-cba)(1,10-phen)(H2O)2](NO3) (4-Hcba = 4-cyanobenzoic acid) has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data: C20H16CuN4O7, Mr= 487.91, triclinic, space group PI, a = 7.8420(2), b = 9.1070(2), c = 15.1140(6) A, a = 76.889(9), β = 81.332(11), γ = 74.844( 11)°, V = 1009.89(5) A^3, Z = 2, Dc = 1.605 g/cm^3, F(000) = 498, μ = 1.134 mm^-1, the final R = 0.0379 and wR = 0.0865 for 2977 observed reflections with 1 〉 2σ(Ⅰ). The Cu(Ⅱ) atom is coordinated by two terminal water molecules, one chelating 1,10-phen molecule and one monodentate 4-cba ligand to form a slightly distorted square pyramid. The title complex molecules are connected through hydrogen bonds and π-π stacking interactions to generate a 2D layered network. The thermogravimetric analysis of the title complex has also been discussed. 展开更多
关键词 copper(Ⅱ) complex 4-cyanobenzoic acid crystal structure hydrogen bonds π-π stacking
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Crystal Structure, Thermal Behavior and Luminescence of a New Copper Coordination Polymer Constructed with 4-(Carboxymethoxy)-benzoic Acid 被引量:3
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作者 WANG Xiu-Yan LI Guan-Ting +3 位作者 WANG Heng SONG Yu LIU Dong-Xue XU Zhan-Lin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第4期629-634,共6页
A new Cu(Ⅱ) coordination polymer, [Cu(L1)(L2)](1), was synthesized under hydrothermal conditions(H_2L1 = 4-(carboxymethoxy)benzoic acid, L2 = 2-(4-fluorophenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline). Crystallograph... A new Cu(Ⅱ) coordination polymer, [Cu(L1)(L2)](1), was synthesized under hydrothermal conditions(H_2L1 = 4-(carboxymethoxy)benzoic acid, L2 = 2-(4-fluorophenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline). Crystallographic data for 1: triclinic, space group P1 with a = 9.750(5), b = 10.148(5), c = 12.869(5) ?, α = 104.904(5), β = 102.133(5), γ = 95.219(5)°, V = 1188.7(10) ?~3, Z = 2, C_(28)H_(17)FN_4O_5Cu, Mr = 572.01, D_c = 1.598 g/cm^3, F(000) = 582, μ(MoKa) = 0.977 mm^(-1), R = 0.0474 and w R = 0.1144. The TGA behaviors and luminescence of 1 have been studied in detail. The L1 dianions link neighboring Cu(Ⅱ) atoms in a bis-chelating mode, yielding a one-dimensional chain structure along the b axis. The L2 ligands are attached on one side of the chain through chelating the Cu(Ⅱ) atoms, and are stacked with those of an adjacent chain through π-π interactions, yielding a layer structure. Additionally, the N–H???O hydrogen bonds further stabilize the structure of 1. 展开更多
关键词 crystal structure COORDINATION polymer 4-(carboxymethoxy)benzoic acid copper(Ⅱ) LUMINESCENT property
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