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Function toggle of tumor microenvironment responsive nanoagent for highly efficient free radical stress enhanced chemodynamic therapy

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Nano Research 2022年第9期15卷 8228-8236页

作者： Xueting Yang Shuaitian Guo Li Wang Shanyue Guan Shuyun Zhou Jun Lu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Beijing Advanced Innovation Center for Soft Mater Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

In contrast to reactive oxygen species(ROS),the generation of oxygen-irrelevant free radicals is oxygen-and H2O2-independent in cell,which can offer novel opportunities to maximum the chemodynamic therapy(CDT)***,an H2O2-independent“functional reversion”strategy based on tumor microenvironment(TME)-toggled C-free radical generation for CDT is developed by confining astaxanthin(ATX)on the NiFe-layered double hydroxide(LDH)nanosheets(denoted as ATX/LDH).The unique ATX/LDH can demonstrate outstanding TME-responsive C-free radical generation performance by proton coupled electron transfer(PCET),owing to the specific ATX activation by unsaturated Fe sites on the LDH nanosheets formed under ***,the Brönsted base sites of LDH hydroxide layers can promote the generation of neutral ATX C-free radicals by capturing the protons generated in the ATX activation ***,ATX/LDH maintain antioxidant performance to prevent normal tissue cancerization due to the synergy of LDH nanosheets and antioxidative *** addition,C-free radical can compromise the antioxidant defense in cells to the maximum extent,compared with *** free radicals burst under TME can significantly elevate free radical stress and induce cancer cell *** strategy can realize TME-toggled C free radical generation and perform free radical stress enhanced CDT.

关键词： ultrathin layered double hydroxide nanosheets astaxanthin free radical chemodynamic therapy

free radical RING OPENING POLYMERIZATION OF CYCLIC ACRYLATES

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Chinese Journal of Polymer Science 1992年第4期10卷 350-355页

作者：冯品珍 Department of Chemistry Graduate School Academia Sinica Beijing

Cyclic acrylates, 2,2- dimethyl-5-methylene-1 , 3-dioxolan-4 -one and 2- phenyl-5-methylene-1,3-dioxolan-4-one, were synthesized successfully. The monomers were characterized by ~1H NMR, ^(13)C NMR, IR and elemental analysis or HRMS. Polymerization of the monomers were carried out at 120℃ with di-t-butylperoxide as initiator. The polymers were studied by ~1H NMR, ^(13)C NMR, UV and hydrolysis. The molecular weights of the resulting polymers were estimated by viscosity measurement and the extent of ring opening was estimated also by ~1H NMR and hydrolysis of the polymers and further confirmed by UV spectra.

关键词： free radical Ring-opening Polymerization Cyclic acrylate.

free radical scavenging window of infertile patients with polycystic ovary syndrome： correlation with embryo quality

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Frontiers of Medicine 2017年第2期11卷 247-252页

作者： Bo Huang Zhou Li Xinling Ren Jihui Ai Lixia Zhu Lei Jin Reproductive Medicine Center Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030China

The activity of free radicals in follicular fluid was related to ovarian responsiveness, in vitro fertilization （IVF）, and embryo transfer success rate. However, studies analyzing the relationship between the free radical scavenging capacity and embryo quality of infertile women with polycystie ovarian syndrome （PCOS） were lacking. The aim of this study was to evaluate the relationship between the free radical scavenging window of women with PCOS and their embryo quality. The free radical scavenging capacity of follicular fluid from women with PCOS was determined by a,a-diphenyl-b-picrylhydrazyl （DPPH）, 2,2-azinobis （3-ethylbenzthiazoline-6- sulphonic acid） assay, superoxide radical, and reactive oxygen species （ROS） assay. In the DPPH and ROS assays, the follicular fluid from grades I and II embryos was significantly higher than the follicular fluid from grades III and IV embryos. The lower control limit of DPPH radical scavenging capacity and upper control limit of ROS level were 13.2% and 109.0 cps, respectively. The calculated lower control limit and upper control limit were further confirmed in the follicular fluid of embryos of all grades. These cut-off values of free radical scavenging activity of follicular fluid could assist embryologists in choosing the development of embryos in PCOS patients undergoing IVF.

关键词： in vitro fertilization PCOS free radical embryo quality

free radical mediated bromization of methylenecyclopropanes: Preparation of 2,4-dibromobutenes without transition metal

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Chinese Chemical Letters 2007年第2期18卷 121-123页

作者： Lei Yu Bo Chen Xian Huang Lu Ling Wu Department of Chemistry Zhejiang University (Campus Xixi) Hangzhou 310028 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A series of 2,4-dibromobutenes were synthesized by the reaction of methylenecyclopropanes with KBr in HOAc in the presence of dibenzoyl peroxide, providing an environment friendly method for the synthesis of 2,4-dibro... 详细信息

关键词： Methylenecyclopropane free radical Bromine

Antioxidative Effect of Schiff Bases with o-Hydroxybenzylidene Groupon free radical Induced Hemolysis of Human Red Blood Cell

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Chemical Research in Chinese Universities 2002年第3期18卷 287-289页

作者： LUO Xu yang ZHAO Jian zhang LIN Ying jie LIU Zai qun College of Chemistry Jilin UniversityChangchun 130023P.R.China

The hemolysis of human red blood cells was initiated by a water soluble free radical initiator, 2,2′ azobis (2 amidinopropane hydrochloride)(AAPH), at 37 ℃ in phosphate buffered saline(pH=7.4). The respective addition of 1 [ N (o hydroxybenzylidene)amino]tetradecane(TDCA), 1,2 di[ N (o hydroxybenzylidene)amino]cyclohexane(DACH), 4 [ N (o hydroxybenzylidene)amino]benzoic acid(PABA), 4 nitro[ N (o hydroxybenzylidene)]aniline(APNA) or N (o hydroxybenzylidene)aniline(APA) can all prolong the inhibition period of hemolysis, indicating that the above Schiff bases play an antioxidative role in free radical induced hemolysis. It can be concluded that Schiff base with an alkyl group or a conjugated system in the molecule protect red blood cells against free radical induced hemolysis efficiently. This information may be useful for antioxidant drug design.

关键词： Red blood cell Hemolysis Schiff base free radical

Autooxidation Mechanism of Pyrogallol and Its free radical Effects Studied by Means of ESR,UV and NMR

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Chemical Research in Chinese Universities 1999年第2期15卷 54-59页

作者： LIU Shanlin ZHAO Baolu SHI Dongyun XIN Wenjuan Department of Biochemistry Shanghai Medical UniversityShanghai200032 Institute of Biophysics Academia SinicaBeijing100101

ＩｎｔｒｏｄｕｃｔｉｏｎＰｙｒｏｇａｌｏｌ（ｐｙｒｏｇａｌｉｃａｃｉｄ）ｉｓｅａｓｉｌｙａｕｔｏ－ｏｘｉｄｉｚｅｄ，ｆｏｒｍｉｎｇｆｒｅｅｒａｄｉｃａｌｓｕｎｄｅｒａｌｋａｌｉｎｅｃｏｎｄｉｔｉｏｎｓ［１］．Ｗｈｅｎ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＰｙｒｏｇａｌｏｌ（ｐｙｒｏｇａｌｉｃａｃｉｄ）ｉｓｅａｓｉｌｙａｕｔｏ－ｏｘｉｄｉｚｅｄ，ｆｏｒｍｉｎｇｆｒｅｅｒａｄｉｃａｌｓｕｎｄｅｒａｌｋａｌｉｎｅｃｏｎｄｉｔｉｏｎｓ［１］．Ｗｈｅｎｔｈｅｂｏｄｙｉｓｓｉｃｋ，ｔｈｅ...

关键词： Pyrogallol free radical ESR NMR UV

Effects of transection of cervical sympathetic trunk on cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2008年第5期3卷 509-512页

作者： Liangzhi Xiong Yongxia Shi Feng Xiao Qingxiu Wang Department of Anesthesiology Taihe Hospital Yunyang Medical College Shiyan 442000 Hubei Province China Department of Anesthesiology Dongfang Hospital Tongji University Shanghai 200120 China

BACKGROUND： Stellate ganglion block （SGB） plays a protective role on the brain, but the precise mechanism of action is not clear. OBJECTIVE： To simulate SGB by transection of the cervical sympathetic trunk （TCST） and to investigate the TCST effects on changes in cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury. DESIGN, TIME AND SETTING： A complete randomized control animal experiment was performed at the Institute of Neurological Diseases of Taihe Hospital, Yunyang Medical College from February to December 2005. MATERIALS： A total of 101 healthy Wistar rats, weighing 280-320 g, of both genders, aged 17-18 weeks, were used in this study. 2, 3, 5-triphenyltetrazolium chloride （TTC） was purchased from Changsha Hongyuan Biological Company. Superoxide dismutase （SOD）, malondialdehyde （MDA） and nitric oxide （NO） assay kits were provided by Nanjing Jiancheng Bioengineering Institute. METHODS： Rats were randomly divided into a TCST group, a model group and a sham operation group. Successful models were included in the final analysis, with at least 20 rats in each group. After TCST, rat models of focal cerebral ischemia/reperfusion injury were established in the TCST group by receiving middle cerebral artery occlusion （MCAO） by the intraluminal suture method for 2 hours, followed by 24 hours of reperfusion. Rat models of focal cerebral ischemia/reperfusion injury were made in the model group. Rats in the sham operation group underwent experimental procedures as for the model group, threading depth of 10 mm, and middle cerebral artery was not ligated. MAIN OUTCOME MEASURES： Brain tissue sections of ten rats from each group were used to measure cerebral infarct volume by TTC staining. Brain tissue homogenate of another ten rats from each group was used to detect SOD activities, MDA contents and NO levels. Rat neurological function was assessed by neurobehavioral measures. RESULTS： Cerebral infarct volume was bigger

关键词： cervical sympathetic trunk ischemia/reperfusion free radical superoxide dismutase malondialdehyde nitric oxide

Biophoton　emission，　free　radical　and　toxicity　of　benzene　to　aquatic　biosystems

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Journal of Environmental Sciences 1996年第2期8卷 218-227页

作者： Wang Yingyan Wang Jiguang(Beijing Municipal Research institute of Environrnental Protection, Beijing 100037, China)Ma Yuqin Su Zhen Zhang Zonglun,Zhao Kejian Zheng Yanzhen Liu Chengxiang(Institute of Biophysics. Chinese Academy of Sciences, Beijing 1 Beijing Munic. Res. Inst. E.P. Beijing 100037 China Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

The observation on biophoton emission, free radical and toxicity of benzene to zebra fish and carp hepatic microsome has demonstrated that there is the corresponding relationship between them by means of 60 Coγ radiolysis. free radicals play a key role in this relationship. A common photon originates of two biosystems are the excited species including singlet and triplet molecules (1O2 and C=0) as well as hydrocyclohexadienyl *** and so on. OH, to a certain extent, directly participates in photon emission and toxicity of benzene to aquatic *** are the conclusions, but these are also problems. With the solution of the latters,model established in this work could be expected that it will be favorable for the development of photon-toxicology.

关键词： biophoton emission free radical benzene aquatic biosystems.

Studies on free radical EPR,Superoxide Dismutase Water-soluble Lipidperoxide in Tears

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Chemical Research in Chinese Universities 1998年第2期14卷 96-101页

作者： YUAN Yi ZHAO Shi-hong YANG Shou CUI Ya-nan ZHANG Rei-xue Ophthalmic Department Center Laboratory of the Third Clinical HospitalNorman Bethune University of Medical Sciences130021 Surveying and Determining of Milk Production’ Harbin150001

By means of electron paramagnetic resonance(EPR), chemistry luminescence and fluorescent spectroscopy, the free radical, superoxide dismutase and water soluble lipid peroxide in tears of normal eyes(150 eyes, 100 cases), Moorens ulcer(9 eyes), coreal grafts rejection(16 eyes) were studied. The results showed that the spin density of the free radical was 36(±058)×1012 spins/mL tear, the content of the superoxide dismutase(SOD) was 384(±145) ng/mL tear, the opposite fluorescent density of the water soluble lipid peroxide was 12912(±1691) U/mL tear in normal tears. The normal values are 25—48×1012 spins/mL tear for free radical, 239—529 ng/mL tear for SOD, 9598—16225 U/mL tear for water soluble lipid peroxide. There are significant differences in different eyes, different sexes and different ages. The free radical and lipid peroxide are higher obviously in the tears of patients with Moorens ulcer and rejected corneal grafts, compared with those of the normal control subjects(Pfree radical. These results have provided important experimental data for studying lacrimalogy and new methods for clinical diagnosis and treatrment.

关键词： free radical Superoxide dismutase Lipid peroxide Corneal ulcer Keratoplasty