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A contribution to the study of the modified Marschalk reaction:Hydroxymethylation of 6,8-O-dimethyl emodin

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Chinese Chemical Letters 2010年第5期21卷 568-571页

作者： Hai shan jin,Li Ming Zhao School of Chemistry and Chemical Engineering,Xuzhou Normal University,Xuzhou 221116,China School of Chemistry and Chemical Engineering Xuzhou Normal University Xuzhou 221116 China

Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk *** influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was *** results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.

关键词： Marschalk reaction Hydroxymethylation Emodin Antitumor activity

Two new ursane-type nortriterpenes from Lonicera macranthoides and their iNOS-inhibitory activities

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Chinese Journal of Natural Medicines 2019年第1期17卷 27-32页

作者： MEI Yu-Dan ZHANG Nan ZHANG Wei-Yang TANG jin-shan ZHOU Hua YU Yang YAO Xin-Sheng Institute of Traditional Chinese Medicine&Natural Products College of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchJinan University XiangXue Academician workstation Xiangxue Pharmaceutical Co.Ltd. College of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Faculty of Chinese Medicine Macao University of Science and Technology and State Key Laboratory of Quality Research in Chinese Medicine(Macao University of Science and Technology)

The flower buds of Lonicera macranthoides(shan Yin-Hua), represent an important traditional Chinese medicine and food ingredient. A phytochemical investigation of the 70% EtOH extract of the flower buds of L. macranthoides resulted in the isolation of 12 triterpenoids(1-12), including two new ursane-type nortriterpenes, 2α, 24-dihydroxy-23-nor-ursolic acid(1) and 2α, 4α-dihydroxy-23-nor-ursolic acid(2). Their structures were established by multiple spectroscopic methods and comparison with literature data. All isolated compounds were evaluated for their anti-inflammatory effects in LPS-activated RAW264.7 cells. Compounds 1 and 2 exhibited inhibitory effects on iNOS at the concentration of 30 μmol·L^(-1).

关键词： Lonicerae Flos Lonicera macranthoides Ursane-type nortriterpenes Anti-inflammation iNOS

Identification of PAL genes related to anthocyanin synthesis in tea plants and its correlation with anthocyanin content

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Horticultural Plant Journal 2022年第3期8卷 381-394页

作者： Xuejin Chen Pengjie Wang Mengya Gu Binghao Hou Churan Zhang Yucheng Zheng Yun Sun shan jin Naixing Ye College of Horticulture Fujian Agriculture and Forestry University/Key Laboratory of Tea Science in University of Fujian ProvinceFuzhou 350002China College of Horticulture Nanjing Agricultural UniversityNanjing 210095China

The phenylalanine ammonia-lyase(PAL)gene family in tea plants(Camellia sinensis L.)encodes the enzyme that catalyzes the first reaction of the phenylpropane metabolic *** present study aimed to characterize the PAL genes in tea plants,and get better insights on the CsPALs in anthocyanins *** CsPAL genes were identified and characterized in tea plants by bioinformatics *** analysis of CsPALs was conducted for its phylogenetic relationship,gene structure,chromosomal location,and protein conserved motifs based on tea plant *** cis-elements of CsPALs were responsive to light,abiotic stress,hormone,and MYB-binding ***,tissuespecific expression analysis showed that CsPAL4 was expressed preferentially in young leaves and *** analysis was performed in purple-leaf tea with anthocyanin components,and it was suggested that CsPAL4 was closely related with different anthocyanin accumulated,especially with cyanidin 3-O-galactoside,cyanidin 3-O-glucoside,and delphinidin ***,the putative upstream regulation factors CsMYBs(CsMYB59,CsARR1,CsSRM1,CsMYB101,and CsMYB52)and CsbHLHs(CsbHLH104,CsbHLH3,CsbIM1,CsTCP14,and CsPIF4)could bind to the promoter of CsPALs,thereby activating its *** study provides a theoretical basis for further research to elucidate the functions of the CsPAL genes.

关键词： Camellia sinensis Phenylalanine ammonia-lyase(PAL) Anthocyanin biosynthesis Expression pattern

Physiological and histological responses of Phascolosoma esculenta (Sipuncula: Phascolosomatidea) to acute heat stress

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Journal of Oceanology and Limnology 2022年第2期40卷 643-655页

作者： Xinming GAO Haiyan YANG Daojun TANG Chen DU shan jin Congcong HOU Chundan ZHANG Junquan ZHU Jianping WANG Key Laboratory of Applied Marine Biotechnology by the Ministry of Education School of Marine SciencesNingbo UniversityNingbo 315211China Ningbo Academy of Oceanology and Fisheries Ningbo 315012China

Temperature is an important factor affecting the growth,development,and survival of *** effects of temperature stress on aquatic organisms have received increasing attention,as these organisms are mostly poikilotherms and their body temperature are directly corresponding changes with ambient temperature,resulting in they are easily exposed in temperature ***,little is known about the effects of high temperature on *** this study,we investigated the effects of acute heat stress on malondialdehyde(MDA)concentration,the activities of antioxidant(superoxide dismutase and glutathione peroxidase)and immunity-related(acidic and alkaline phosphatase)enzymes,heat shock protein 70(hsp70)and hsp90 gene expression,and the histological structure of the sipunculid Phascolosoma *** the coelom fl uid,the MDA concentration and all detected antioxidant enzyme activities increased during high temperature stress;signifi cant increases were also observed here and in the intestine in the hsp70 and hsp90 mRNA expression *** results indicated that acute heat stress caused oxidative stress;antioxidants and heat shock proteins probably act to protect *** against oxidative damage,constituting part of its physiological mechanism for adaptation to high *** addition,the increased activity of the acidic and alkaline phosphatases indicated eff ects on its nonspecifi c immune ***,damaged tissue structures were observed in the body wall,retractor muscle,intestine,and nephridium after 96 h of 40-℃ *** damaged cells of these tissues showed obvious condensed chromatin around the nuclear *** histological damage suggests that heat stress could affect movement,food absorption,digestion,and excretion in *** results elucidate the effects of temperature stress on *** and its physiological response mechanisms and provide practical indicators for assessing heat stress status and determi

关键词： heat stress oxidation stress enzyme activity heat shock proteins nonspecific immunity histological damage

Effect of high magnetic field on solidification microstructure evolution of a Cu-Fe immiscible alloy

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China Foundry 2022年第4期19卷 335-341页

作者： Yu-jie Yan Chen Wei Yi-xuan He Chao Li Ping-xiang Zhang jin-shan Li Jun Wang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Xi'an Superconducting Magnet Technology Co. Ltd.Xi'an 710018China Northwest Institute for Nonferrous Metal Research Xi'an 710016China

The liquid phase separation behavior and the evolution of the solidification microstructure of a binary Cu_(50)Fe_(50) alloy were investigated under the conditions of without and with a 10 T magnetic field,with different undercooling during the solidification *** show that the combined effect of Stokes motion and Marangoni convection leads to the formation of the core-shell structure under the condition without the magnetic *** addition,specific gravity segregation is reinforced by increasing the undercooling,resulting in Fe-rich phase drifts towards the sample *** the 10 T magnetic field,the Fe-rich phase is elongated in the parallel direction of the magnetic field under the action of demagnetization energy due to the difference of static magnetic energy and surface *** the vertical direction,through the action of Lorentz force,the convection in the melt is inhibited and Fe-rich phase becomes more ***,the diffusion of the two phases and the coagulation of the Fe-rich phases are also restrained under the magnetic field,therefore,the phase volume fraction of the Fe-rich phase decreases at the same undercooling in the 10 T magnetic *** magnetic field inhibits the segregation behavior in the vertical direction of the magnetic field,and at the same time,improves the gravitational segregation to a certain extent,which has a very important impact on microstructure regulation.

关键词： high magnetic field Cu-Fe immiscible alloy undercooling solidification

Microstructure and properties of mechanical alloying particles reinforced aluminum matrix composites prepared by semisolid stirring pouring method

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China Foundry 2016年第3期13卷 176-181页

作者： Yao-qiang Si Zhi-yong You jing-xin Zhu Lai-qiang Cai jin-shan Zhang College of Materials Science and Engineering Taiyuan University of Technology

Aluminum matrix composites reinforced with mechanical alloying particles(SiC_p) were fabricated by the semisolid stirring pouring method. The inf luence of mechanical alloying particles and Mg on the microstructure and mechanical properties of the composites was investigated by means of optical microscopy(OM), X-ray diffraction scanning(XRD), electron microscopy(SEM) and energy dispersive spectroscopy(EDS). Results show that the addition of Mg converts the agglomerate mechanical al oying particles in ZL101 matrix composites into dispersed distribution in ZL101-Mg matrix composites, large matrix grains into f ine equiaxed matrix grains, and eutectic phase into f ine particles. So the mechanical properties of ZL101-Mg matrix composites are better than those of ZL101 matrix composites. The mechanical properties of ZL101/ZL101-Mg matrix composites are gradually increased with the increase of the volume fraction of mechanical alloying particles. When the volume fraction of mechanical alloying particles is 3%, the Vickers hardness and ultimate tensile strength of the ZL101/ZL101-Mg matrix composites reach their maximum values.

关键词： mechanical alloying particle aluminum matrix composites grain refinement mechanical properties

Compressive deformation behavior of an indirect-extruded Mg-8Sn-1Al-1Zn alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 49-56页

作者： Wei-li Cheng Zhong-ping Que jin-shan Zhang Chun-xiang Xu Wei Liang Bong Sun You Sung Soo Park School of Materials Science and Engineering Taiyuan University of Technology Korea Institute of Materials Science Ulsan National Institute of Science and Technology

The medium and warm deformation behaviors of an indirect-extruded Mg-8Sn-IAI-IZn alloy were investigated by compression tests at temperatures between 298 and 523 K and strain rates of 0.001-10 s-1. It was found that the twinning-slip transition temperature was strain rate dependent, and all the true stress-true strain curves could be divided into two groups： concave and convex curves. Associated microstructural investigations indicated that the dynamic recrystallization （DRX） be- havior of the alloy varied with deformation conditions. At high strain rate and low temperature, dynamically recrystallized grains preferentially nucleated and developed in the twinned regions, indicating that twinning-induced DRX was dominant. While, at low strain rate, DRX developed extensively at grain boundaries and twins, and the process of twinning contributed to both oriented nucleation and selective growth. For the studied alloy, cracks mainly initiated from the shear band and twinning lamellar over the ranges of temperature and strain rate currently applied.

关键词： magnesium alloys compression testing dynamic recrystallization microstructure

Ulcerative colitis with inflammatory polyposis in a teenage boy:A case report

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World Journal of Gastroenterology 2015年第3期21卷 1044-1048页

作者： jin-shan Feng Ying Ye Can-Can Guo Bo-Tao Luo Xue-Bao Zheng Research Institute of Traditional Chinese Medicine Guangdong Medical College Department of Gastroenterology Guangdong Medical College affiliated Lianjiang Hospital Department of Pathology School of Basic Medicine SciencesGuangdong Medical College

Ulcerative colitis in addition to inflammatory polyposis is *** benign sequel of ulcerative colitis can sometimes mimic colorectal *** report describes a rare case of inflammatory polyposis with hundreds of inflammatory polyps in ulcerative colitiswhich was not easy to distinguish from other polyposis syndromes.A 16-year-old Chinese male suffering from ulcerative colitis for 6 mo underwent colonoscopy,and hundreds of polyps were observed in the sigmoid,causing colonic *** polyps were restricted to the *** rectal inflammation was detected,no polyps were found in the rectum.A diagnosis of inflammatory polyposis and ulcerative colitis was *** patient underwent total colectomy and ileal pouch anal *** patient recovered well and was discharged on postoperative day *** surveillance after surgery is crucial as ulcerative colitis with polyposis is a risk factor for colorectal *** of polyposis requires clinical,endoscopic and histopathologic correlation,and helps with chemoprophylaxis of colorectal cancer,as the drugs used postoperatively for colorectal cancer,ulcerative colitis and polyposis are different.

关键词： Ulcerative colitis Inflammatory polyposis Teenager

Relation Between Endodormancy Induction and Changes in Two Main Electron Transport Pathways of Nectarine Buds

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Agricultural Sciences in China 2008年第10期7卷 1203-1209页

作者： YU Qin GAO Dong-sheng XU Xiao-ming LI jin XU Chen-shan State Key Laboratory of Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an271018. P.R.China

Operation regulations of two main electron transport pathways in nectarine （Prunus persica var. nectariana cv. Shuguang） buds during endodormancy induction were studied to understand possible roles which two main electron transport pathways played in the buds of deciduous fruit trees during endodormancy induction. Respiratory inhibitors （KCN and SHAM） were used to investigate total respiration rate （Vt）, the development and operation of the alternative pathway and partitioning of electrons between the cytochrome and alternative pathways in nectarine buds during endodormancy induction. Results indicated that changes of Vt in flower and leaf buds showed single and double hump-shaped curves, respectively. In endodormancy induction, the capacity （Valt,） and activity （ρValt） of the alternative pathway rapidly increased, but changes of them had different patterns during the entire measuration. At the same time, changes of engagements of the alternative （ρValt/Vt） and cytochrome pathway （ρ′Vcyt/Vt） were opposite, and ρ′Vcyt/Vt was always further higher than ρValt/Vt during the entire measuration. All these results indicated that the development and operation of the alternative pathway played important roles in endodormancy induction, but the cytochrome pathway was the main pathway for mitochondrial electron transport in buds during endodormancy induction.

关键词： nectarine buds endodormancy induction cytochrome pathway alternative pathway