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Remote Control of Bovine Catalase Activity with Specific Frequencies of Human and Bovine Catalase with and without Bound NADP+
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作者 Thibaud Etienne d’Oultremont 《Advances in Enzyme Research》 CAS 2024年第2期17-34,共18页
Remote control enzyme technology is widely used today through resonance. In this study, we showed that the use of frequencies of the catalase enzyme itself to increase enzymatic rate is successful not only in test tub... Remote control enzyme technology is widely used today through resonance. In this study, we showed that the use of frequencies of the catalase enzyme itself to increase enzymatic rate is successful not only in test tubes but also remotely. The present study also suggests that, under optimal temperature, the use of bovine catalase frequency (the specific frequency of that enzyme) has a superior rate promoting vibration than the human catalase frequency, and so increases very significantly the chemical rate of bovine catalase (about 120% at 40˚C). It also suggests that bovine catalase subjected to bovine and human frequencies with catalase bound NADP+ experienced more resonance weight towards NADP+ and so were more slowly reduced back to catalase bound NADPH, increasing compound II formation rate, and slowing down the catalase activity rate. 展开更多
关键词 Remote Control catalase Frequency Rate Promoting Vibration (RPV) NADP
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细叶百合Catalase基因的克隆及表达分析 被引量:1
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作者 宋煜 林文昊 +2 位作者 荆一博 董懿 金淑梅 《植物研究》 CAS CSCD 北大核心 2023年第5期756-767,共12页
为探究细叶百合(Lilium pumilum)Catalase(CAT)基因与耐盐碱胁迫的关系,从细叶百合鳞茎中成功克隆出LpCat基因。该基因的ORF区长度为1479 bp,编码492个氨基酸,对其进行序列比对和系统进化树分析,发现细叶百合Catalase蛋白与通江百合(L.s... 为探究细叶百合(Lilium pumilum)Catalase(CAT)基因与耐盐碱胁迫的关系,从细叶百合鳞茎中成功克隆出LpCat基因。该基因的ORF区长度为1479 bp,编码492个氨基酸,对其进行序列比对和系统进化树分析,发现细叶百合Catalase蛋白与通江百合(L.sargentiae)、菠萝(Ananas comosus)、油棕(Elaeis guineensis)等植物的Catalase蛋白亲缘关系较近。构建了pQE-LpCat原核表达载体,以1 mol·L^(-1)IPTG为诱导剂进行LpCat蛋白的体外诱导表达与纯化。在添加50 mmol·L^(-1)NaHCO_(3)胁迫下,携带PQE-LpCat蛋白的菌液生长浓度高于对照菌株。在1 mol·L^(-1)NaHCO_(3)、2.5 mol·L^(-1)H_(2)O_(2)胁迫下过表达LpCAT基因烟草(Nicotiana plumbaginifolia)植株与野生型相比,枯萎程度相对较低。通过净光合速率、气孔导度、胞间CO_(2)和蒸腾速率,H_(2)O_(2)含量,丙二醛(MDA)等生理指标检测说明过表达LpCat基因烟草植株比野生型烟草植株更耐盐碱。 展开更多
关键词 细叶百合 catalase基因 盐碱逆境
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Effects of Hg^(2+) on Isozymes of Peroxidase,Catalase and Superoxide Dismutase in Wheat Seedlings 被引量:20
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作者 王琳 王林嵩 +4 位作者 王丽 孙向东 宗秀征 李芳军 高雅 《Agricultural Science & Technology》 CAS 2008年第5期19-23,共5页
[Objective] This work was aimed to explore the mechanism of Hg2+ toxicity on plants.[Method]Activities of peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)were investigated in wheat(Triticum aestivum L.)seedl... [Objective] This work was aimed to explore the mechanism of Hg2+ toxicity on plants.[Method]Activities of peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)were investigated in wheat(Triticum aestivum L.)seedlings under Hg2+ stress at different concentrations.[Result]① There were no obvious effects on the growth of seedlings when the concentration of Hg2+ was lower than 0.10 mmol/L.However,toxic effects on the growth of seedling were observed when the concentration of Hg2+ was higher than 0.10 mmol/L.② Different tissues showed different resistant ability in response to Hg2+ stress.The leaves and roots of wheat seedlings were more insensitive to Hg2+ toxicity.③ CAT was more sensitive to Hg2+ stress compared to POD and SOD.[Conclusion]The toxic effect was related to the concentration of Hg2+(0.10 mmol/L).The higher concentration of Hg2+ could affect the expression of POD,CAT,and SOD isozymes in the leaves,roots of wheat seedlings and germinated seeds,which further affect the normal metabolism of membrane lipid and inhibit the growth of wheat seedlings at last. 展开更多
关键词 Wheat Hg2+ stress PEROXIDASE catalase Superoxide DISMUTASE ISOZYME
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幽门螺杆菌Catalase基因的克隆、表达及其抗原性鉴定 被引量:6
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作者 李妍 宁云山 +2 位作者 龙敏 董文其 李明 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2006年第4期440-442,446,共4页
目的:构建含人幽门螺杆菌(Hpylori,Hp)过氧化氢酶(catalase,KatA)编码基因的重组质粒,测定、分析其核酸序列,并在E.coli中表达,研究其抗原性。方法:应用PCR技术从HpDNA染色体中扩增KatA编码基因片段,将其T-A克隆和测序,并... 目的:构建含人幽门螺杆菌(Hpylori,Hp)过氧化氢酶(catalase,KatA)编码基因的重组质粒,测定、分析其核酸序列,并在E.coli中表达,研究其抗原性。方法:应用PCR技术从HpDNA染色体中扩增KatA编码基因片段,将其T-A克隆和测序,并与GenBank公布的其他Hp菌株的基因序列比较,再将目的基因插入至融合表达载体pGEX-4T-1中进行表达,用GST亲和层析对其进行纯化。纯化产物用于对29株小鼠抗Hp-全菌单克隆抗体(mAb)的鉴定及与Hp啊感染患者血清进行Western blot。结果:KatA基因全长为1 515 bp,并在GenBank上登录(No.DQ333889),与GenBank公布的其他Hp菌株的核酸的同源性为96%~97%,表达的KatA融合蛋白的相对分子质量(Mr)为85 000,29株小鼠抗Hp全菌mAb中有4株mAb是针对KatA的,表达产物可被Hp感染患者的血清特异性识别。结论:重组KatA具有较好的抗原性,为坳检测试剂和疫苗的研究奠定了基础。 展开更多
关键词 幽门螺杆菌 catalase 克隆 基因表达 抗原性
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Cloning and Differential Gene Expression of Two Catalases in Suaeda salsa in Response to Salt Stress 被引量:6
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作者 马长乐 王萍萍 +2 位作者 曹子谊 赵彦修 张慧 《Acta Botanica Sinica》 CSCD 2003年第1期93-97,共5页
Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ... Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ( L.) Pall aerial tissue. Sscat1 (1.7 kb) contains a full open reading frame of 492 amino acids and Sscat2 (1.1 kb) is a partial clone. BLAST analysis indicates that the two clones share 71.9% identity in nucleotide sequence and 75% identity in deduced amino acid sequence within the last 287 amino acid residues of Sscat1. Southern blotting analysis showed that Sscat1 is multicopy in S. salsa genome, while Sscat2 is a single copy gene. Northern blotting analysis showed a rapid increase in the steady-level of both genes in roots after 48 It salt treatment, but only Sscat1 was induced in salinity treated leaves. Time-course analysis carried out in leaves confirmed that Sscat1 was induced by salt stress, in contrast to Sscat2. These implied that the expression of Sscat1 and Sscat2 genes are differentially regulated in S. salsa. The activity of total catalase is dramatically increased in response to salt stress. 展开更多
关键词 catalase salt stress Suaeda salsa reactive oxygen species
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Effects of Catalase and Ascorbate Peroxidase on the Root Growth of Rice under Cadmium Stress 被引量:9
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作者 宋新华 王凯 +1 位作者 郭蕾蕾 赵凤云 《Agricultural Science & Technology》 CAS 2011年第9期1256-1259,共4页
[Objective] The research aimed to study the correlations between catalase(CAT) and ascorbate peroxidase(ASP) and the growth and development of rice roots under cadmium stress.[Method] Taking rice variety Zhonghua ... [Objective] The research aimed to study the correlations between catalase(CAT) and ascorbate peroxidase(ASP) and the growth and development of rice roots under cadmium stress.[Method] Taking rice variety Zhonghua No.11 as materials,the changes of rice seedlings under the treatment conditions of Cd,Cd+CAT inhibitor,Cd+APX inhibitor were studied.[Result] Under Cd stress,inhibition of CAT activity caused the significant inhibition on the growth of aerial parts,decreased the number of adventitious roots and lateral roots,but it can significant promote the elongation growth of adventitious roots and lateral roots.Moreover,the length of the first lateral root from root tip on the primary roots and adventitious roots was also increased than control.When APX activity was inhibited,the growth changes of rice were similar with that treated by CAT inhibitor.[Conclusion] CAT and APX may play important roles in the regulation of rice root system growth in both non-stress and Cd-stressed rice 展开更多
关键词 Cd stress catalase Ascorbate peroxidase
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幽门杆菌Catalase/GST融合蛋白的表达、标签切除及鉴定 被引量:6
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作者 姜茵 奚月 李妍 《生物技术通报》 CAS CSCD 北大核心 2012年第2期102-106,共5页
旨在利用GST融合基因表达系统表达幽门螺杆菌Catalase融合蛋白,并利用凝血酶切除GST标签。将重组质粒Catalase/pGEX-4T-1转化大肠杆菌BL21(DE3)感受态中,用IPTG进行诱导表达,菌体经反复冻融、溶菌酶裂解及超声破菌后,Catalase/GST融合... 旨在利用GST融合基因表达系统表达幽门螺杆菌Catalase融合蛋白,并利用凝血酶切除GST标签。将重组质粒Catalase/pGEX-4T-1转化大肠杆菌BL21(DE3)感受态中,用IPTG进行诱导表达,菌体经反复冻融、溶菌酶裂解及超声破菌后,Catalase/GST融合蛋白以部分可溶性的形式表达在上清中。采用谷胱甘肽琼脂糖树脂Glutathione Sepharose 4B对其进行纯化,得到Catalase/GST融合蛋白,再用凝血酶进行GST标签的切除,所得产物进行Western blotting鉴定。高效表达出Catalase/GST融合蛋白的相对分子质量约85 kD,凝血酶成功地切除了GST标签,Western blotting证实Catalase蛋白能被鼠抗Catalase单克隆抗体识别。 展开更多
关键词 幽门螺杆菌 catalase 融合表达 GST标签切除 纯化
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Response of soil catalase activity to chromium contamination 被引量:23
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作者 Zofia Stepniewska Agnieszka Wolińska Joanna Ziomek 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第8期1142-1147,共6页
The impact of chromium(Ⅲ) and (Ⅵ) forms on soil catalase activity was presented. The Orthic Podzol, Haplic Phaeozem and Mollic Gleysol from different depths were used in the experiment. The soil samples were ame... The impact of chromium(Ⅲ) and (Ⅵ) forms on soil catalase activity was presented. The Orthic Podzol, Haplic Phaeozem and Mollic Gleysol from different depths were used in the experiment. The soil samples were amended with solution of Cr(Ⅲ) using CrCl3, and with Cr(Ⅵ) using K2Cr2O7 in the concentration range from 0 to 20 mg/kg, whereas the samples without the addition of chromium served as control. Catalase activity was assayed by one of the commonly used spectrophotometric methods. As it was demonstrated in the experiment, both Cr(Ⅲ) and Cr(Ⅵ) have an ability to reduce soil catalase activity. A chromium dosage of 20 mg/kg caused the inhibition of catalase activity and the corresponding contamination levels ranged from 75% to 92% for Cr(Ⅲ) and 68% to 76% for Cr(Ⅵ), with relation to the control. Catalase activity reached maximum in the soil material from surface layers (0-25 cm), typically characterized by the highest content of organic matter creating favorable conditions for microorganisms. 展开更多
关键词 CHROMIUM catalase enzymatic activity INHIBITION
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Modulatory effect of pineapple peel extract on lipid peroxidation,catalase activity and hepatic biomarker levels in blood plasma of alcoholinduced oxidative stressed rats 被引量:13
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作者 Okafor OY Erukainure OL +3 位作者 Ajiboye JA Adejobi RO Owolabi FO Kosoko SB 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第1期12-14,共3页
Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood plasma.Meth... Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood plasma.Methods:Oxidative stress was induced by oral administration of ethanol(20%w/v) at a dosage of 5 niL/kg bw in rats.After 28 days of treatment,the rats were fasted overnight and sacrificed by cervical dislocation.Blood was collected with a 2 mL syringe by cardiac puncture and was centrifuged at 3000 rpm for 10 min.The plasma was analyzed to evaluate malondialdehyde(MDA),catalase activity,aspartate aminotransferase(AST),alkaline phosphatase(ALP) and alanine aminotransferase(ALT) concentrations.Results:Administration of alcohol caused a drastic increase(87.74%) in MDA level compared with the control.Pineapple peel extract significantly reduced the MDA level by 60.16%at 2.S mL/kg bw.Rats fed alcohol only had the highest catalase activity,treatment with pineapple peel extract at 2.5 mL/kg bw however, reduced the activity.Increased AST,ALP and ALT activities were observed in rats fed alcohol only respectively,treatment with pineapple peel extract drastically reduced their activities. Conclusions:The positive modulation of lipid peroxidation,catalase activities as well as hepatic biomarker levels of blood plasma by the methanolic extract of pineapple peels under alcoholinduced oxidative stress is an indication of its protective ability in the management of alcoholinduced toxicity. 展开更多
关键词 Blood PLASMA catalase LIPID peroxide Aspartate AMINOTRANSFERASE Alkaline phosphatase Alanine AMINOTRANSFERASE HEPATIC BIOMARKER Pineapple peel EXTRACT Oxidative stress LIPID peroxidation
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Cloning of catalase and expression patterns of catalase and selenium-dependent glutathione peroxidase from Exopalaemon carinicauda in response to low salinity stress 被引量:6
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作者 REN Hai LI Jian +4 位作者 LI Jitao YING Yu GE Hongxing LI Dongli YU Tianji 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期52-61,共10页
Catalase (CAT) and selenium-dependent glutathione peroxidase (Se-GPx) play a vital role in protecting organisms against various oxidative stresses by eliminating H202, The objective of this paper is to evaluate th... Catalase (CAT) and selenium-dependent glutathione peroxidase (Se-GPx) play a vital role in protecting organisms against various oxidative stresses by eliminating H202, The objective of this paper is to evaluate the roles of these antioxidant molecules in the ridgetail white prawn Exopalaemon carinicauda in response to low salinity stress. A complementary DNA (cDNA) containing the complete coding sequence of CAT was cloned from the hepatopancreas using reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends. The full-length cDNA of CAT (2 649 bp) contains a 5'-untranslated region (UTR) of 78 bp, a 3'- UTR of 1 017 bp, with a poly (A) tail, and an open reading frame of 1 554 bp encoding a 517-amino-acid polypeptide with predicted molecular mass of 58.46 kDa and estimated isoelectric point of 6.64. This CAT sequence contained the proximal active site signature (60FDRERIPERWHAKGAG76), proximal heme-ligand signature sequence (350RLFSYPDTH358) and three catalytic amino acid residues (His71, Asn144 and Tyr354). Sequence comparison showed that the CAT deduced amino acid sequence of E. carinicauda shared 68%-92% of identities with those of other species. Quantitative real-time PCR analysis revealed that CAT mRNA was widely expressed in the hepatopancreas (highest), hemocyte, eyestalk, heart, gill, muscle, ovary and stomach. Under low salinity stress, CAT and GPx mRNA expression levels both in the gill and hepatopancreas increased significantly at the first 48 h and 6 h respectively, indicating a tissue- and time-dependent antioxidant response in E. carinicauda. All these results indicate that E. carinicauda CAT is a member of the CAT family and might be involved in the acute response against low salinity stress. 展开更多
关键词 Exopalaemon carinicauda catalase (CAT) selenium-dependent glutathione peroxidase (Se-GPx) CLONING expression
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Inflammation/bioenergetics-associated neurodegenerative pathologies and concomitant diseases:a role of mitochondria targeted catalase and xanthophylls 被引量:6
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作者 Mikhail A.Filippov Olga G.Tatarnikova +1 位作者 Natalia V.Pozdnyakova Vasily V.Vorobyov 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第2期223-233,共11页
Various inflammatory stimuli are able to modify or even"re-program"the mitochondrial metabolism that results in generation of reactive oxygen species.In noncommunicable chronic diseases such as atheroscleros... Various inflammatory stimuli are able to modify or even"re-program"the mitochondrial metabolism that results in generation of reactive oxygen species.In noncommunicable chronic diseases such as atherosclerosis and other cardiovascular pathologies,type 2 diabetes and metabolic syndrome,these modifications become systemic and are characterized by chronic inflammation and,in particular,"neuroinflammation"in the central nervous system.The processes associated with chronic inflammation are frequently grouped into"vicious circles"which are able to stimulate each other constantly amplifying the pathological events.These circles are evidently observed in Alzheimer's disease,atherosclerosis,type 2 diabetes,metabolic syndrome and,possibly,other associated pathologies.Furthermore,chronic inflammation in peripheral tissues is frequently concomitant to Alzheimer's disease.This is supposedly associated with some common genetic polymorphisms,for example,Apolipoprotein-Eε4 allele carriers with Alzheimer's disease can also develop atherosclerosis.Notably,in the transgenic mice expressing the recombinant mitochondria targeted catalase,that removes hydrogen peroxide from mitochondria,demonstrates the significant pathology amelioration and health improvements.In addition,the beneficial effects of some natural products from the xanthophyll family,astaxanthin and fucoxanthin,which are able to target the reactive oxygen species at cellular or mitochondrial membranes,have been demonstrated in both animal and human studies.We propose that the normalization of mitochondrial functions could play a key role in the treatment of neurodegenerative disorders and other noncommunicable diseases associated with chronic inflammation in ageing.Furthermore,some prospective drugs based on mitochondria targeted catalase or xanthophylls could be used as an effective treatment of these pathologies,especially at early stages of their development. 展开更多
关键词 algae xanthophylls Alzheimer's disease atherosclerosis depression type 2 diabetes metabolic syndrome mitochondria-targeted catalase noncommunicable chronic diseases stress
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Association of Catalase Genotype with Oxidative Stress in the Predication of Colorectal Cancer:Modification by Epidemiological Factors 被引量:2
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作者 CHANG Dong HU Zhang Liang +5 位作者 ZHANG Lin ZHAO Ya Shuang MENG Qing Hui GUAN Qing Bai ZHOU Jin PAN Hong Zhi 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第2期156-162,共7页
Objective This paper aims to assess the interaction between common variations in catalase(CAT) polymorphic gene and environmental factors for antioxidant defense enzyme in modulating individual susceptibility to col... Objective This paper aims to assess the interaction between common variations in catalase(CAT) polymorphic gene and environmental factors for antioxidant defense enzyme in modulating individual susceptibility to colorectal cancer(CRC).Methods A case-control study with 880 colorectal cancer cases and 848 controls was conducted to investigate whether variations in the catalase(CAT) gene,one of the genes involved in scavenging oxidative stress,influenced susceptibility to CRC.Results The interaction between life style and genotypes as well as with their effects on colorectal cancer was deduced from the present study.Significant difference(P=0.01) was identified in the distribution of CAT genotype between the colorectal cancer cases and the controls.The CRC cases had significantly lower mean activity than the controls(P〈0.01).Correlation analyses revealed statistically significant correlations between CAT activity and CAT genotype(P〈0.01).Conclusion The risk of CRC was associated with smoking,low vegetable consumption,high pork and poultry consumptions,and low or high BMI.This is the first study reporting an association of polymorphism CAT-21A〉T with colorectal cancer.Low CAT activity was associated with an increased risk of CRC;however,no evidence was found to support an association between CAT-21A〉T polymorphism and CRC risk. 展开更多
关键词 Colorectal cancer (CRC) Oxidative stress catalase (CAT) gene Epidemiological factors
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Mailuoning suppresses H_2O_2-induced cortical neuronal injury and correlates with increased catalase activity and inhibited oxidative stress function 被引量:1
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作者 Xiaofan Pan Siyuan Huang +1 位作者 Lingling Li Yun Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第8期611-617,共7页
BACKGROUND:Mailuoning, a Chinese herb, has been widely used in China to treat acute ischemic stroke, and the major component exhibits anti-oxidative effects. However, the precise anti-oxidation pathway remains uncert... BACKGROUND:Mailuoning, a Chinese herb, has been widely used in China to treat acute ischemic stroke, and the major component exhibits anti-oxidative effects. However, the precise anti-oxidation pathway remains uncertain.OBJECTIVE:To validate the protective effects of Mailuoning on H202-induced primary cortical neuron injury in embryonic mice.DESIGN, TIME AND SETTING:Comparative observation and in v#ro experiments were performed at the Jiangsu Key Laboratory for Molecular Medicine from January 2008 to September 2009.MATERIALS:Mailuoning (Nanjing Jinling Medical Company, China), reactive oxygen species (ROS) kit (Beyotime Biotechnology, China), superoxide dismutase (SOD), Cu/Zn SOD kit, malondialdehyde (MDA) kits (Nanjing Jiancheng, China), mitochondrial membrane potential (GMS10013.1, GENMED, USA) and catalase activity assay kit (Beyotime Biotechnology, China) were utilized for the present study.METHODS:Mouse embryonic cortical neurons were isolated and cultured with culture medium containing H2O2 (80 μmol/L) and/or Mailuoning (1.25 μg/mL) for 24 hours.MAIN OUTCOME MEASURES:Neuronal viability and death were detected by methyl thiazolyl tetrazdium and flow cytometry; ROS production was determined by flow cytometry; mitochondriai membrane potential was detected using fluorescent staining; SOD activity was detected using a modified nitroblue tetrazolium method; Cu/Zn SOD and catalase activity was detected by spectrophotometry; and MDA was determined using the lipid peroxidation method.RESULTS:H2O2 increased ROS production and MDA concentration (P 〈 0.05), and decreased mitochondrial membrane potential, SOD, Cu/Zn SOD and catalase activity (P 〈 0.05); the number of surviving neurons (P 〈 0.05) was also reduced. Mai/uoning reversed these changes.CONCLUSION:Mailuoning protects H2O2-induced injury in cortical cells by inhibiting ROS and MDA, increasing depolarization of mitochondrial membrane, and enhancing SOD and catalase activity. 展开更多
关键词 MAILUONING oxidative stress NEURONS reactive oxygen species catalase activity traditional Chinese medicine mice brain injury neural regeneration
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HIGHLY SENSITIVE CATALASE ELECTRODE BASED ON POLYPYRROLE FILMS WITH MICROCONTAINERS 被引量:1
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作者 Yu-ying Gao Gao-quan Shi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第6期579-584,共6页
Highly sensitive catalase electrodes for sensing hydrogen peroxide have been fabricated based on polypyrrole films with microcontainers. The microcontainers have a cup-like morphology and are arranged in a density of ... Highly sensitive catalase electrodes for sensing hydrogen peroxide have been fabricated based on polypyrrole films with microcontainers. The microcontainers have a cup-like morphology and are arranged in a density of 4000 units cm^-2. Catalase was immobilized into the polypyrrole films with microcontainers (Ppy-mc), which were coated on a Pt substrate electrode. The catalase/Ppy-mc/Pt electrode showed linear response to hydrogen peroxide in the range of 0-18 mmol/L at a potential of-0.3 V (versus SCE). Its sensitivity was measured to be approximately 3.64 μA (mmol/L) ^-1 cm^- 2, which is about two times that of the electrode fabricated from a flat Ppy film (catalase/Ppy-flat/Pt electrode). The electrode is highly selective for hydrogen peroxide and its sensitivity is interfered by potential interferents such as ascorbic acid, urea and fructose. Furthermore, such catalase electrodes showed long-term storage stability of 15 days under dry conditions at 4℃. 展开更多
关键词 Microstructured polypyrrole catalase ELECTROPOLYMERIZATION SENSORS Hydrogen peroxide.
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Glutathione peroxidase, superoxide dismutase and catalase activities in children with chronic hepatitis 被引量:2
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作者 Nagwa Abdallah Ismail Sawsan H. Okasha +3 位作者 Anil Dhawan Azza M. O. Abdel Rahman Nehal Abdel Hamid Olfat Shaker 《Advances in Bioscience and Biotechnology》 2012年第7期972-977,共6页
The advantages of measuring hepatic oxidative status in liver biopsy are that it helps in diagnosis of hepatic dysfunction, reflects the degree of deterioration in the liver tissues, and helps to determine the severit... The advantages of measuring hepatic oxidative status in liver biopsy are that it helps in diagnosis of hepatic dysfunction, reflects the degree of deterioration in the liver tissues, and helps to determine the severity of hepatic injury. We aimed to study the oxidative stress state in children with chronic hepatitis by using indirect approach in which antioxidant enzymes such as glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) are determined in the liver tissue. The present study included 21 children and adolescents (12 males, 9 females) suffering from chronic hepatitis. Patients were selected from the Hepatology Clinic, New Children’s Hospital, Cairo University from November 2006 till 2009 and compared with a group of 7 children who happened to have incidental normal liver biopsy. Children with chronic hepatitis had mean age 8.12 ± 1.15 years. It was further subdivided into 2 subgroups: chronic viral heaptitis (n = 13) and cryptogenic hepatitis (n = 8). GPX, SOD and CAT levels were measured in fresh liver tissue (cell free homogenates) using ELISA. In chronic hepatitis group;there was a significant increase in the hepatic GPX activity (38.59 ± 35.82 nmol/min/ml) as compared to the control group (10.62 ± 6.68 nmol/min/ml). Also a significant correlation was observed between SOD and both ALT (r = 0.87, p < 0.05) and AST (r = 0.74, p < 0.05). GPX correlated with ALT (r = 0.80, p < 0.05) level in the chronic viral hepatitis subgroup. Our findings suggest that oxidative stress could play a role in the pathogenesis of chronic hepatitis. These preliminary results are encouraging to conduct more extensive clinical studies combining antioxidant therapy with various treatments. 展开更多
关键词 GLUTATHIONE PEROXIDASE Superoxide DISMUTASE catalase Chronic HEPATITIS Oxidative Stress
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Investigating Catalase and Carbonic Anhydrase Enzyme Activities and Levels of Certain Trace Elements and Heavy Metals in Patients with Primary and Metastatic Hepatic Carcinoma 被引量:1
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作者 Ayse Arslan Halit Demir Harun Arslan 《Journal of Cancer Therapy》 2013年第8期1373-1381,共9页
Hepatocellular carcinoma (HCC) is among most common terminal cancer types in the world. Primary etiological factors include cirrhosis, hepatitis, aflatoxin and alcohol. The current study was conducted to determine cyt... Hepatocellular carcinoma (HCC) is among most common terminal cancer types in the world. Primary etiological factors include cirrhosis, hepatitis, aflatoxin and alcohol. The current study was conducted to determine cytosolic erythrocyte carbonic anhydrase and catalase enzyme activities and levels of some trace elements. For this purpose, 40 patients with primary and metastatic hepatic cancer and 29 healthy volunteers enrolled to the study. Catalase and carbonic anhydrase enzyme activities and serum trace element levels were measured in patient and control groups. In the current study, serum copper, magnesium, manganese and zinc levels were lower in the primary and metastatic hepatic cancer group in comparison with the control group (P < 0.05). In contrast, serum iron, cobalt, cadmium and lead levels were higher in the patient relative to the control group (P < 0.05). In comparison with the control group, the catalase level was lower in primary and metastatic cancer group, while the carbonic anhydrase level was higher in the cancer group (P < 0.05). Changes in levels of trace elements and anti-oxidant enzymes may be the factors which influence the development and progression of liver cancer. The carbonic anhydrase enzyme can be a useful indicator in the diagnosis of cancer. However, this issue warrants further investigation. 展开更多
关键词 PRIMARY and METASTATIC Liver Cancer catalase Carbonic ANHYDRASE Trace Element Heavy Metal
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Effect of Petroleum Products on Soil Catalase and Dehydrogenase Activities 被引量:1
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作者 Fidelis Ifeakachuku Achuba Patrick Nwanze Okoh 《Open Journal of Soil Science》 2014年第12期399-406,共8页
The effect of refined petroleum products on the activities of selected enzymes (catalase and dehydrogenase) was studied. There was a significant decrease (p kerosene > diesel > engine oil. However, a significant... The effect of refined petroleum products on the activities of selected enzymes (catalase and dehydrogenase) was studied. There was a significant decrease (p kerosene > diesel > engine oil. However, a significant increase (p diesel > petrol > engine oil. On the whole the results reveal that refined petroleum products alter soil biochemistry. 展开更多
关键词 catalase ACTIVITY DEHYDROGENASE ACTIVITY KEROSENE DIESEL Engine Oil PETROL
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Osmolyte modulated enhanced rice leaf catalase activity under salt-stress 被引量:1
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作者 Sushmita Sahu Priyanka Das +1 位作者 Mamata Ray Surendra Chandra Sabat 《Advances in Bioscience and Biotechnology》 2010年第1期39-46,共8页
Change in catalase activity was examined in leaves of rice plant exposed to salinity. Depending on the method of preparation of crude protein extract from leaf and the constituents of the assay medium, a significant d... Change in catalase activity was examined in leaves of rice plant exposed to salinity. Depending on the method of preparation of crude protein extract from leaf and the constituents of the assay medium, a significant difference in enzyme activity was recorded. Inclusion of sorbitol or mannitol or sucrose in the extraction and enzyme assay medium enhanced the enzyme activity in salt-stressed samples by nearly 1.5-1.8 fold, compared to the activity found in un- stressed plants, which otherwise showed a 50% declined activity in leaf extract prepared in buffer solution and assayed in a medium depleted of these sugars. In view of the accumulation of osmolytes under saline condition, these observations suggest that the catalase activity is modulated by the osmolytes and maintains a high rate of hydrogen peroxide scavenging property in vivo and serves as the major antioxidant enzyme to scavenge the salt-induced formation of peroxide. Therefore, the salt-stress induced appearance of low activity of the enzyme under normal buffer extraction and assay conditions, as reported in literature may represent an apparent than for its real in vivo activity. 展开更多
关键词 catalase Activity Hydrogen PEROXIDE OSMOLYTE Rice SALT-STRESS
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<i>Staphylococcus aureus</i>Can Produce Catalase Enzyme When Adding to Human WBCs as a Source of H<sub>2</sub>O<sub>2</sub>Productions in Human Plasma or Serum in the Laboratory 被引量:1
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作者 Hiba Siddig Ibrahim Mustafa 《Open Journal of Medical Microbiology》 2014年第4期249-251,共3页
Background: Staphylococcus aureus is one of the most virulent gram positive bacteria. It produces a lot of toxins and enzymes, most of which are virulent factors. Among the enzyme that produces is the catalase which i... Background: Staphylococcus aureus is one of the most virulent gram positive bacteria. It produces a lot of toxins and enzymes, most of which are virulent factors. Among the enzyme that produces is the catalase which is very useful in differentiating staphylococci from streptococci [1]. Catalase is nearly ubiquitous among some of organisms that can grow in the presence of oxygen (air). It promotes the conversion of hydrogen peroxide, a powerful and potentially harmful oxidizing agent, to water and molecular oxygen;so the major function of catalase within cells is to prevent the accumulation of toxic levels of hydrogen peroxide formed as a by-product of metabolic processes—primarily that of the electron transport pathway. Objectives: The main aim of this study is to prove that human WBCs can produce H2O2. This H2O2 when reacting with catalase producing S. aureus can easily be degraded to H2O + O2. Methodology: In this study a total of 40 subjects were included. Aliquots of 2.5 ml of venous blood were collected by venous puncture after disinfecting the site of collection with 70% alcohol and the collected blood was drawn into EDITA containers (20 subject) and anticoagulant free containers (other 20 subject), centrifugation for 5 minute at 1500 RPM. The separated sera and plasma were converted to new sterile eppendrof tubes and freezing until used (we leaved the eppendrof tubes that contained sera and plasma at room temperature before using it for DE freezing). Standard catalase producing S. aureus were used by taking 1 colony from Macconkey media by using applicator wooden stick, and inserted in eppendrof tube, then air bubbles would appear to indicate occurrence of the reactions. Results: According to this study, it was proved that WBCs in human plasma or serum can produce H2O2;this H2O2 was reacted with catalase enzyme produce from colony of S. aureus to produce air bubbles and water. There were no differences between using H2O2 or human plasma/serum that contains WBCs to detect and identify S. aureus by both techniques. Conclusion: Based on the results of this study, we can use WBCs that are found in human plasma or serum to identify catalase producing S. aureus. 展开更多
关键词 WBCs catalase ENZYME S. aureu
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精神分裂症患者与过氧化氢酶(Catalase)基因多态性
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作者 赵昌烈 李光哲 +1 位作者 崔成虎 许妍姬 《中国民康医学》 2009年第13期1484-1487,共4页
目的:探讨过氧化氢酶(Catalase)基因多态性与精神分裂症的相关性。方法:采用Amp-RFLP(amplication-restriction freg-ment lengh polymorphis)方法对精神分裂症患者和对照组的过氧化氢酶基因相关性进行了研究。结果:167例精神分... 目的:探讨过氧化氢酶(Catalase)基因多态性与精神分裂症的相关性。方法:采用Amp-RFLP(amplication-restriction freg-ment lengh polymorphis)方法对精神分裂症患者和对照组的过氧化氢酶基因相关性进行了研究。结果:167例精神分裂症患者与155例对照组之间过氧化氢酶基因型频率和等位基因频率无统计学意义,76例女性精神分裂症患者与60例对照组之间过氧化氢酶基因型频率(x^2=11.096,df=2,P=0.004)有显著性差异。结论:过氧化氢酶多态性与精神分裂症的遗传学并不存在关联性,但是研究表明过氧化氢酶基因型频率与女性精神分裂症患者有显著性差异。 展开更多
关键词 精神分裂症 过氧化氢酶(catalase) 基因多态性
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