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Photo-induced Coupling Reaction of 1,1-Diphenyl-2,2-dicyanoethylene with 10-Methyl-9,10-dihydroacridine
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作者 HongJIANG YouChengLIU +3 位作者 GuanWuWANG ShiWeiLUO QuanMingWANG ThomasC.W.MAK 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第2期159-162,共4页
Diphenyl-2, 2-dicyanoethylene reacts with 10-methyl-9, 10-dihydroacridine in deaerated acetonitrile under irradiation with l>320 nm to give the coupling product 1, 1-diphenyl-1-(10-methyl-9-acridinyl)-2, 2-dicyanoe... Diphenyl-2, 2-dicyanoethylene reacts with 10-methyl-9, 10-dihydroacridine in deaerated acetonitrile under irradiation with l>320 nm to give the coupling product 1, 1-diphenyl-1-(10-methyl-9-acridinyl)-2, 2-dicyanoethane, which has been characterized by X-ray crystallographic, MS and NMR analyses. 展开更多
关键词 Photo-induced coupling reaction 1 1-diphenyl-2 2-dicyanoethylene 10-methyl-9 10-dihydroacridine 1 1-diphenyl-1-(10-methyl-9-acridinyl)-2 2-dicyanoethane.
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SYNTHESIS OF 3,4-DIPHENYL-1.3,4-DIAZAPHOSPHOLID1N-2-ONE-4-OXIDE BY MANNICH-TYPE REACTION 被引量:1
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作者 Ru Yu CHEN Ke Sheng FENG Institute of Elemento-Organic Chemistry,Nankai University,Tianjin 300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期11-14,共4页
Phenylurea reacted with dichlorophenylphosphine and aldehydes or ketones by Mannich-type reaction in anhydrous benzene to give five-mem- bered phosphorous heterocyclic compounds.However.derivatives of α-ureidoalkylph... Phenylurea reacted with dichlorophenylphosphine and aldehydes or ketones by Mannich-type reaction in anhydrous benzene to give five-mem- bered phosphorous heterocyclic compounds.However.derivatives of α-ureidoalkylphosphonic acids were obtained as the reaction performed in glacial acetic acid. 展开更多
关键词 NH JP IR HCH SYNTHESIS OF 3 4-diphenyl-1.3 4-DIAZAPHOSPHOLID1N-2-ONE-4-OXIDE BY MANNICH-TYPE REACTION ppm CCH
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Genome-wide association mapping of vitamins B1 and B2 in common wheat 被引量:5
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作者 Jieyun Li Jindong Liu +5 位作者 Wei'e Wen Pingzhi Zhang Yingxiu Wan Xianchun Xia Yan Zhang Zhonghu He 《The Crop Journal》 SCIE CAS CSCD 2018年第3期263-270,共8页
Vitamin B is essential for maintaining normal life activities in humans and animals who have to intake the microelement from the outside, especially from cereal products. In the present study 166 Chinese and foreign w... Vitamin B is essential for maintaining normal life activities in humans and animals who have to intake the microelement from the outside, especially from cereal products. In the present study 166 Chinese and foreign wheat cultivars planted in two environments were characterized for variation in vitamin B1 and B2 contents. A genome-wide association study(GWAS) using the wheat 90 K SNP assay identified 17 loci for vitamin B1 and 7 for vitamin B2 contents. Linear regression analysis showed a significantly positive correlation of the number of favorable alleles with vitamin B1 and B2 contents. Marker-trait associations(MTAs) at IWB43809(6AS, 0cM) and IWB69903(6AS, 13cM) were new and stable, and significantly associated with vitamin B1 content across two environments. The loci identified in this study and associated SNP markers could be used for improvement of vitamin B1 and B2 contents to obtain superior quality along with grain yield in wheat. 展开更多
关键词 90 K SNP assay GWAS Vitamin B1 Vitamin B2 Triticum aestivum
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Synthesis and Crystal Structure of 1,2-Dis(1,3-diphenylpropan-2-yl)disulfane
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作者 冯附 黄猛 +4 位作者 王乾有 段正超 涂海洋 张爱东 胡卫兵 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第9期1275-1278,共4页
A novel compound of 1,2-dis(1,3-diphenylpropan-2-yl)disulfane(C30H30S2,Mr=454.27)was synthesized in ethanol with 1,3-diphenyl-2-propanone as raw materials,giving high yield of product(90%).Its structure was dete... A novel compound of 1,2-dis(1,3-diphenylpropan-2-yl)disulfane(C30H30S2,Mr=454.27)was synthesized in ethanol with 1,3-diphenyl-2-propanone as raw materials,giving high yield of product(90%).Its structure was determined by IR,1H NMR,MS,elemental analysis and X-ray diffraction.The crystal belongs to monoclinic,space group C2 with a=18.727(3),b=6.5179(9),c=13.7576(18),β=131.0610(10)o,V=1266.2(3)3,Z=2,Dc=2.136 g/cm3,μ=1.078 mm-1,F(000)=843,R=0.0490 and wR=0.1247 for 3211 observed reflections with I2(I).X-ray analysis reveals that the molecule is not symmetrical.There exist no classical hydrogen bonds andπ-πstacking interactions.Moreover,the thermal stability of compound 3 was investigated. 展开更多
关键词 1 3-diphenyl-2-propanone synthesis crystal structure
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Global hypomethylation in hepatocellular carcinoma and its relationship to aflatoxin B_1 exposure 被引量:5
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作者 Hulya Yazici Ming-Whei Yu +1 位作者 Po-Huang Lee Regina M Santella 《World Journal of Hepatology》 CAS 2012年第5期169-175,共7页
AIM:To determine global DNA methylation in paired hepatocellular carcinoma(HCC) samples using several different assays and explore the correlations between hypomethylation and clinical parameters and biomarkers,includ... AIM:To determine global DNA methylation in paired hepatocellular carcinoma(HCC) samples using several different assays and explore the correlations between hypomethylation and clinical parameters and biomarkers,including that of aflatoxin B 1 exposure.METHODS:Using the radio labeled methyl acceptance assay as a measure of global hypomethylation,as well as two repetitive elements,including satellite 2(Sat2) by MethyLight and long interspersed nucleotide elements(LINE1),by pyrosequencing.RESULTS:By all three assays,mean methylation levels in tumor tissues were significantly lower than that in adjacent tissues.Methyl acceptance assay log(mean ± SD) disintegrations/min/ng DNA are 70.0 ± 54.8 and 32.4 ± 15.6,respectively,P = 0.040;percent methylation of Sat2 42.2 ± 55.1 and 117.9 ± 88.8,respectively,P < 0.0001 and percent methylation LINE1 48.6 ± 14.8 and 71.7 ± 1.4,respectively,P < 0.0001.Aflatoxin B 1 albumin(AFB 1-Alb) adducts,a measure of exposure to this dietary carcinogen,were inversely correlated with LINE1 methylation(r =-0.36,P = 0.034).CONCLUSION:Consistent hypomethylation in tumor compared to adjacent tissue was found by the three different methods.AFB 1 exposure is associated with DNA global hypomethylation,suggesting that chemical carcinogens may influence epigenetic changes in humans. 展开更多
关键词 Hepatocellular carcinoma EPIGENETICS HYPOMETHYLATION [3 H]-methyl acceptance assay Satellite 2 Long interspersed nucleotide element-1 Aflatoxin B_1
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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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Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis 被引量:2
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作者 Zhihong Chen Songhe Yang +2 位作者 Yaqiang He Chengjun Song Yongping Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第19期1756-1764,共9页
Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus m... Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats. 展开更多
关键词 neural regeneration traditional Chinese medicine SERICIN type 2 diabetes mellitus hippocampus growth hormone insulin-like growth factor 1 growth hormone receptor growth hormone/insulin-likegrowth factor 1 axis STREPTOZOTOCIN blood glucose western blot assay reverse transcription-PCR grants-supported paper NEUROREGENERATION
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Imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 may contribute to hemorrhage in cerebellar arteriovenous malformations
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作者 Fei Di Tongyan Chen +4 位作者 Hongli Li Jizong Zhao Shuo Wang Yuanli Zhao Dong Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第19期1513-1519,共7页
In this study, we determined the expression levels of matrix metalloproteinase-2 and -9 and matrix metalloproteinase tissue inhibitor-1 and -2 in brain tissues and blood plasma of patients undergoing surgery for cereb... In this study, we determined the expression levels of matrix metalloproteinase-2 and -9 and matrix metalloproteinase tissue inhibitor-1 and -2 in brain tissues and blood plasma of patients undergoing surgery for cerebellar arteriovenous malformations or primary epilepsy (control group). Immunohistochemistry and enzyme-linked immunosorbent assay revealed that the expression of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 was significantly higher in patients with cerebellar arteriovenous malformations than in patients with primary epilepsy. The ratio of matrix metalloproteinase-9 to matrix metalloproteinase tissue inhibitor-1 was significantly higher in patients with hemorrhagic cerebellar arteriovenous malformations compared with those with non-hemorrhagic malformations. Matrix metalloproteinase-2 and matrix metalloproteinase tissue inhibitor-2 levels were not significantly changed. These findings indicate that an imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-I, resulting in a relative overabundance of matrix metalloproteinase-9, might be the underlying mechanism of hemorrhage of cerebellar arteriovenous malformations. 展开更多
关键词 cerebellar arteriovenous malformations HEMORRHAGE matrix metalloproteinase-2 matrixmetalloproteinase-9 tissue matrix metalloproteinase inhibitor-1 tissue matrix metalloproteinaseinhibitor-2 IMMUNOHISTOCHEMISTRY enzyme-linked immunosorbent assay neural regeneration
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Antioxidant Activity Evaluation in a Series of Heterocyclic Compounds Derived from 1,8-Diaminonaphthalene
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作者 Tuo Nanou Tiéba Kangah Niameke Jean Baptiste +4 位作者 Ballo Daouda Kablan Ahmont Landry Claude Kodjo Charles Guillaume Yapo Ossey Bernard Ziao Nahossé 《Journal of Biophysical Chemistry》 2021年第1期1-9,共9页
From (2,3-dihydro-1<i>H</i>-perimidin-2-yl)-phenyl, the substitution of OH group in <i>ortho</i> or <i>para</i> position on the phenyl ring, allows us to synthesize the studied comp... From (2,3-dihydro-1<i>H</i>-perimidin-2-yl)-phenyl, the substitution of OH group in <i>ortho</i> or <i>para</i> position on the phenyl ring, allows us to synthesize the studied compounds. These three compounds have been characterized by conventional spectroscopic methods (NMR and MS). The interest of this work is to review the antioxidant activity of our compounds. The antioxidant activity screening carried out according to FRAP and DPPH methods revealed significant anti-free radical properties for compounds 1 and 2 even at low concentrations. In contrast to the compound 2, compound 3 for which the OH group is substituted in <i>para</i> position has the lowest activity in both cases. Therefore the <i>para</i> position seems to be the least sensitive position to increase the antioxidant activity of this pharmacophore. 展开更多
关键词 PERIMIDINE SPECTROMETRY Antioxidant Activity 2 2-diphenyl-1-picrylhydrazyl Method and Ferric Reducing Antioxidant Power Method
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An In Vitro and In Vivo Study of Thyroid Disruption of 1,2-Bis(2,4,6-tribromophenoxy)ethane(BTBPE)�A Novel Brominated Flame Retardant
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作者 Na Zheng Na Li +9 位作者 Lei Lei Biran Zhu Kun Qiao Qiangwei Wang Chengqian Liang Yongyong Guo Lihua Yang Jian Han Yuxi Zhou Bingsheng Zhou 《Environment & Health》 2024年第1期42-51,共10页
The novel brominated flame retardant,1,2-bis-(2,4,6-tribromophenoxy)ethane(BTBPE),is an emerging environ-mental pollutant with undetermined toxicity.We investigated how BTBPE causes thyroid endocrine disruption with i... The novel brominated flame retardant,1,2-bis-(2,4,6-tribromophenoxy)ethane(BTBPE),is an emerging environ-mental pollutant with undetermined toxicity.We investigated how BTBPE causes thyroid endocrine disruption with integrated in silico,in vitro,and in vivo assays.In yeast two-hybrid and T-Screen assays,BTBPE interacted with zebrafish thyroid hormone receptors with binding energies weaker than the TR agonist-3,3′,5-Triiodo-L-thyronine(T3),and disrupted thyroid function as a thyroid receptor(TR)agonist.We examined the bioconcentra-tion,developmental toxicity,and thyroid endocrine disruption in zebrafish after a 14-day exposure to BTBPE(1,3,10μg/L).Thyroxine(T4)was lower in BTBPE-treated larvae,whereas corticotropin-releasing hormone(CRH)and thyroid-stimulating hormone(TSH)were higher.The gene transcription alterations along the hypothalamic-pituitary-thyroid(HPT)axis were observed.Furthermore,reduced locomotion suggested that BTBPE imparts developmental neurotoxicity at zebrafish early developmental stage.Establishing that BTBPE has thyroid endocrine-disrupting effects is an important step for understanding and managing BTBPE toxicity. 展开更多
关键词 1 2-bis(4 6-tribromophenoxy)ethane THYROID endocrine disrupting developmental neurotoxicity yeast two-hybrid assay T-screen assay zebrafish larvae
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Morphology Control over the Organic Nanoparticles of 1,3-Diphenyl-5-(9-anthryl)-2-pyrazoline
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作者 奚璐 肖德宝 +2 位作者 杨文胜 姚建年 张宝文 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2003年第12期1532-1535,共4页
The organic nanoparticles of a blue-light-emitting molecule,1,3-diphenyl-5-(9-anthryl)-2-pyrazoline,were prepared by reprecipitation method using acetonitrile as the solvent for the molecular precursor. Three morpholo... The organic nanoparticles of a blue-light-emitting molecule,1,3-diphenyl-5-(9-anthryl)-2-pyrazoline,were prepared by reprecipitation method using acetonitrile as the solvent for the molecular precursor. Three morphologies,spherical,doughnut-shaped and cubic,could be observed on the silicon substrate for the nanoparticles by the volume-controlled addition of acetonitrile. The evolution of particle morphology as a function of acetonitrile addition was attributed to the variation of the growth habits of the particles in the different environment. The nanoparticles exhibit the novel photoluminescence spectra as compared to those of monomer and the bulk crystals. 展开更多
关键词 organic nanoparticles morphology control reprecipitation method 1 3-diphenyl-5-(9-anthryl)-2-pyrazoline PHOTOLUMINESCENCE
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Rat cardiomyocyte H9c2(2-1)-based sulforhodamine B assay as a promising in vitro method to assess the biological component of effluent toxicity
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作者 Elsa T Rodrigues Susana F Nascimento +2 位作者 Maria Joao Moreno Paulo J Oliveira Miguel A Pardal 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第10期163-170,共8页
The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human health.Wastewater quality evaluation is conventionally based... The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human health.Wastewater quality evaluation is conventionally based on physicochemical parameters,but increasing attention has been paid to integrate physicochemical and biological data.Nevertheless,the regulatory use of fish in biological testing methods has been subject to various ethical and cost concerns,and in vitro cell-based assays have thus become an important topic of interest.Hence,the present study intends:(a) to evaluate the efficiency of two different sample pre-concentration techniques (lyophilisation and solid phase extraction) to assess the toxicity of municipal effluents on rat cardiomyoblast H9c2(2-1) cells,and (b) maximizing the use of the effluent sample collected,to estimate the environmental condition of the receiving environment.The gathered results demonstrate that the H9c2(2-1) sulforhodamine B-based assay is an appropriate in vitro method to assess biological effluent toxicity,and the best results were attained by lyophilising the sample as pre-treatment.Due to its response,the H9c2(2-1) cell line might be a possible alternative in vitro model for fish lethal testing to assess the toxicity of municipal effluents.The physicochemical status of the sample suggests a high potential for eutrophication,and iron exceeded the permissible level for wastewater discharge,possibly due to the addition of ferric chloride for wastewater treatment.In general,the levels of carbamazepine and sulfamethoxazole are higher than those reported for other countries,and both surpassed the aquatic protective values for long-term exposure. 展开更多
关键词 Municipal wastewater treatment plant effluent LYOPHILISATION Solid phase extraction Cell-based assays H9c2(2-1)cell line SRB assay
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Decline in the expression of IL-2 after trauma and changes in the nuclear transcription factors NFAT and AP-1 被引量:1
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作者 罗艳 梁华平 +2 位作者 胡承香 徐祥 王正国 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第9期1348-1351,150,共4页
OBJECTIVE: To investigate whether the decrease in expression of interleukin-2 (IL-2) after trauma is associated with changes in DNA binding activity of nuclear factor of activated T cells (NFAT) and activator protein-... OBJECTIVE: To investigate whether the decrease in expression of interleukin-2 (IL-2) after trauma is associated with changes in DNA binding activity of nuclear factor of activated T cells (NFAT) and activator protein-1 (AP-1). METHODS: Mice with closed impact injury with fracture in both hind limbs were adopted as the trauma model. Spleen lymphocytes were isolated from traumatized mice and stimulated with Con-A. Culture supernatants were assayed for IL-2 activity, and total RNA was extracted from spleen lymphocytes and assayed for IL-2 mRNA. DNA binding activity of NFAT and AP-1 were measured by electrophoretic mobility shift assay (EMSA). The expression of c-Fos, c-Jun and JunB proteins was determined by the Western blot analysis. RESULTS: DNA binding activity of NFAT and AP-1 gradually decreased to a minimum of 41% and 49%, respectively, of the control on the 4th day after injury, which was closely followed by the decline in IL-2 activity and IL-2 mRNA. A decrease in the expression of c-Fos on the 1st and 4th day after trauma had no significant effect on c-Jun expression; the increase in expression of JunB was only on the 1st day after injury. CONCLUSION: Decreased IL-2 expression is, at least in part, due to a decline in the activation of NFAT and AP-1 in traumatized mice. The decline in DNA binding activity of NFAT and AP-1 is partly due to a trauma-induced block in the expression of c-Fos. 展开更多
关键词 Nuclear Proteins Animals Cell Nucleus DNA DNA-Binding Proteins Electrophoretic Mobility Shift assay Female INTERLEUKIN-2 Male Mice NFATC Transcription Factors Proto-Oncogene Proteins c-fos Proto-Oncogene Proteins c-jun RNA Messenger Research Support Non-U.S. Gov't Transcription Factor AP-1 Transcription Factors
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Synthesis of 3,3,5,5-tetrabenzyl-1,2,4-trithiol and 1,2-dis(1,3-arylpropan-2-yl)disulfane
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作者 Fu Feng Meng Huang +1 位作者 Zheng-Chao Duan Wei-Bing Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第10期909-911,共3页
Novel sulfur-containing compounds (3a-3c, 4a-4c) were obtained in ethanol with 1,3-diphenyl-2- propanone as the starting material. The advantages of this procedure were mild reaction conditions, simple protocol, and... Novel sulfur-containing compounds (3a-3c, 4a-4c) were obtained in ethanol with 1,3-diphenyl-2- propanone as the starting material. The advantages of this procedure were mild reaction conditions, simple protocol, and high yields. The structures of the products were characterized by IR, 1H NMR, MS and elementary analysis. The crystal of the new compound 4a belongs to monoclinic, space group C2 with a=18.727(3), b=6.5179(9), c=13.7576(18) A, fl=131.0610(10)°, V=I266.2(3)A3, Z=2, Dc=2.136g/cm3, μ=1.078mm 1, F(000)=843, R=0.0490 and wR=0.1247 for 3211 observed reflection with I 〉 2σ(I). X-ray analysis reveals that the molecule is not symmetrical, the molecular structure is stabilized by weak π-π stacking interactions, and no classical hydrogen bonds can be observed. 展开更多
关键词 1 3-diphenyl-2-propanone Synthesis Sulfur-containing compounds
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The Application of Novel Electrochemical Approach to Antioxidant Activity Assay of Metal Porphyrins with Bulky 3,5-Diisobornyl-4-hydroxyphenyl Moieties
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作者 Tatyana Rocheva Vladimir Tyurin +6 位作者 Dmitrii Belykh Аnna Moiseeva Jingwei Zhang Еvgeny Buravlev Irina Chukicheva Alexander Alexander Kutchin Elena Milaeva 《American Journal of Analytical Chemistry》 2014年第15期1028-1036,共9页
The complexes of biogenic metals (Zn2+,Cu2+,Co2+,Mn3+,Fe3+) based on meso-tetra(3,5-diisobor- nyl-4-hydroxyphenyl)porphyrin 1 were synthesized. The electrochemical behavior of these com-pounds was studied using cyclic... The complexes of biogenic metals (Zn2+,Cu2+,Co2+,Mn3+,Fe3+) based on meso-tetra(3,5-diisobor- nyl-4-hydroxyphenyl)porphyrin 1 were synthesized. The electrochemical behavior of these com-pounds was studied using cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The antioxidant activity of complexes was estimated by means of the electrochemical assay based on the hydrogen atom transfer reaction to the stable radical 2,2’-diphenyl-1-picrylhydrazyl (DPPH). The RDE method was applied for this process monitoring. It was shown that the efficiency of the metal complexes (Cu2+,Co2+,Mn2+,Ni2+,Fe3+) is practically the same order as that of free base porphyrin 1. However the Zn2+ complex demonstrates significantly higher antioxidant activity, and the stoichiometry of the reaction was determined as σ = 4. The results demonstrate that porphyrin macrocycle can directly affect the antioxidant properties of 2,6-diisobornylphenol. 展开更多
关键词 METAL PORPHYRINS Cyclic VOLTAMMETRY Rotating Disk Electrode 2 2-diphenyl-1-picrylhydrazyl ANTIOXIDANT Activity
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后发酵过程中乙醇对豆豉抗氧化能力的影响 被引量:13
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作者 邹磊 汪立君 +2 位作者 呼晴 李里特 八卷幸二 《食品与发酵工业》 CAS CSCD 北大核心 2006年第12期28-32,共5页
以黄豆为原材料,接种米曲霉制作豆豉,在豆豉后发酵过程中设定了不同乙醇添加量,测定了不同乙醇添加量的豆豉样品清除DPPH(2,2-diphenyl-1-picrylhydrazyl hydrate)及ABTS[2,2-’azinobis-(3-ethylbenzthia-zoline-6-sulfonic acid)]自... 以黄豆为原材料,接种米曲霉制作豆豉,在豆豉后发酵过程中设定了不同乙醇添加量,测定了不同乙醇添加量的豆豉样品清除DPPH(2,2-diphenyl-1-picrylhydrazyl hydrate)及ABTS[2,2-’azinobis-(3-ethylbenzthia-zoline-6-sulfonic acid)]自由基能力、Fe2+螯合能力、还原能力,评价了乙醇对豆豉抗氧化能力的影响。后发酵过程中,豆豉的抗氧化能力持续增大,醇对豆豉的抗氧化能力有影响,发酵相同时间的豆豉,抗氧化能力随乙醇含量的增大而下降。 展开更多
关键词 豆豉 抗氧化 乙醇 DPPH(2 2-diphenyl-1-picrylhydrazyl hydrate) ABTS[2 2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid)] 多肽
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Synthesis of a New β-Mercaptoalcohol 被引量:1
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作者 Jian Feng GE Li Fen ZHANG +1 位作者 Zong Xuan SHEN Ya Wen ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第7期569-570,共2页
In this letter, (R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol was synthesized from L-valine and two synthetic routes have been tried.
关键词 R)-1 1-diphenyl-2-mercapto-3-methyl-1-butanol asymmetric synthesis L-valine.
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A Comparative Study of Antioxidant Activities between Fresh and Dry Mushrooms in the Genera <i>Cantharellus</i>and <i>Afrocantharellus</i>from Tanzania
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作者 Donatha Damian Tibuhwa 《Food and Nutrition Sciences》 2014年第2期212-221,共10页
Cantharellus and Afrocantharellus mushrooms are widely consumed in both fresh and dry forms. However, their antioxidant and whether their values changing with drying processes are not known. This study establishes the... Cantharellus and Afrocantharellus mushrooms are widely consumed in both fresh and dry forms. However, their antioxidant and whether their values changing with drying processes are not known. This study establishes their values and the effect of sun drying on their quality and quantity. Methanolic extracts of five Cantharellus and two Afrocantharellus species were investigated. The investigation used (1,1-diphenyl-2-picrylhydrazyl radical) DPPH as a substrate to determine radical scavenging abilities. Further quantitative analyses for carotenoids, flavonoid, total phenolic compounds and vitamin C content were done using spectrophotometric assay at 515 nm. Comparatively, fresh mushroom had higher vitamin C and Lycopene contents than their dry counterparts with β-carotene. Flavonoid and phenolic compounds were higher in dry forms than those in their fresh counterparts. Radical scavenging ability also varied with fresh forms depicting higher activity compared to dry forms. The variation was low in Afrocantharellus species (0.8% and 0.99%) while it was higher in Cantharellus species (24.12% and 7.52%). The highest ability was observed in fresh forms of Cantharellus pseudocibarius (EC50 50 = 0.4 mg/ml) was from dry form of Cantharellus rufopunctatus. This shows that studied mushrooms are rich in antioxidants and their quality and quantities are affected differently in both forms. Both dry and fresh mushrooms are potential sources of natural antioxidants. The portrayed high scavenging ability by these mushrooms envisages promoting them into potential nutraceutics. 展开更多
关键词 ANTIOXIDANT Activity FRESH MUSHROOMS Sun-Dried MUSHROOMS Afrocantharellus Cantharellus 1 1-diphenyl-2-picrylhydrazyl
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Effect of Induced Mutation on Antioxidant Activity in Ocimum basilicum Linn
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作者 Isaac Kojo Asante Kofi Annan +1 位作者 Matthew Kweku Essilfie Valentine Tater 《Natural Science》 2016年第4期192-195,共4页
Five batches from the same stock of seeds of Ocimum basilicum were irradiated at 5, 10, 15, 20 and 25 Gy, respectively using <sup>60</sup>C source. Methanolic leaf extracts of these samples and a control w... Five batches from the same stock of seeds of Ocimum basilicum were irradiated at 5, 10, 15, 20 and 25 Gy, respectively using <sup>60</sup>C source. Methanolic leaf extracts of these samples and a control were evaluated for their antioxidant activity by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging method using M<sub>2</sub> plants. All the methanolic extracts showed antioxidant activity. The IC<sub>50</sub> of the methanolic extracts of the six different treatments, control, 5 Gy, 10 Gy, 15 Gy, 20 Gy and 25 Gy, showed antioxidant activity with IC<sub>50</sub> values of 100, 90, 86, 61, 71 and 70 μg/ml, respectively. Three individual mutants, M-15-5, M-20-6 and M-15-4, had IC<sub>50</sub> values of 26, 30 and 40 μg/ml, respectively. These mutants were from the 15 Gy and 20 Gy treatments. From the results, it is confirmed that induced mutation can be employed to create variation in the levels of free radical scavenging activity in O. basilicum and can therefore serve as a tool for breeding for high levels of antioxidant activity in O. basilicum. 展开更多
关键词 Ocimum basilicum Nonirradiated Irradiated Antioxidant Activity MUTANT 1 1-diphenyl-2-picryl-hydrazyl
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In vitro antioxidant activities of ethanol extract from Enhalus acoroides (L.F.) Royle 被引量:15
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作者 Rengasamy Ragupathi Raja Kannan Rajasekaran Arumugam Perumal Anantharaman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第11期898-901,共4页
Objective:To search for new sources of safe and inexpensive antioxidants,the leaf,root and rhizome of Enhalus acoroides(E.acoroides) were screened for the first time for their antioxidant activities.Methods:Samples of... Objective:To search for new sources of safe and inexpensive antioxidants,the leaf,root and rhizome of Enhalus acoroides(E.acoroides) were screened for the first time for their antioxidant activities.Methods:Samples of leaf,root and rhizome from E.acoroides were tested for total phenolic content,proanthocyanidins and in vitro antioxidant activity in terms of total antioxidant assay,DPPH assay and FRAP assay.Results:The leaf sample was found to have high levels of phenolic(0.323±0.028 mg TAE/g) and proanthocyanidins(0.570 0±0.000 3 mg TAE/g) when compared to root and rhizome.The leaf samples exhibited higher total antioxidant activity (11.770±0.026 mg Ascorbic acid equivalent/g),higher percentage of DPPH radical scavenging activity(25.76±0.04) and higher reducing power(18.060±0.073) in terms of mg GAE/g.In addition, there was a significant correlation between total phenolic content and total antioxidant activity (R^2=0.923),DPPH assay(R^2=0.509).FRAP assay(R^2=0.994).Similarly,significant correlation was found between the proanthocyanidin and total antioxidant activity(R^2=0.977),DPPH assay (R^2=0.464) and the FRAP assay(R^2=0.998).Conclusions:These results suggested that E.acoroides have strong antioxidant potential.Further study is necessary for isolation and characterization of the active antioxidant agents,which can be used to treat various oxidative stress-related diseases. 展开更多
关键词 Enhalus acoroides ANTIOXIDANT activity PHENOLIC content DPPH(2 2-diphenyl-1-picrylhydrazyl) FRAP assay
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