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Berberine ameliorates renal injury in streptozotocin-induced diabetic rats by suppression of both oxidative stress and aldose reductase 被引量:42
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作者 LIU Wei-hua HEI Zi-qing +9 位作者 NIE Hong TANG Fu-tian HUANG He-qing LI Xue-juan DENG Yan-hui CHEN Shao-rui GUO Fen-fen HUANG Wen-ge CHEN Feng-ying LIU Pei-qing 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第8期706-712,共7页
Background Berberine is one of the main constituents of Coptidis rhizoma (CR) and Cortex phellodendri. In this study, we investigated the beneficial effects of berberine on renal function and its possible mechanisms... Background Berberine is one of the main constituents of Coptidis rhizoma (CR) and Cortex phellodendri. In this study, we investigated the beneficial effects of berberine on renal function and its possible mechanisms in rats with diabetic nephropathy (DN). Methods Male Wistar rats were divided into three groups: normal, diabetic model, and berberine treatment groups. Rats in the diabetic model and berberine treatment groups were induced to diabetes by intraperitonal injection with streptozotocin (STZ). Glomerular area, glomerular volume, fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (Cr) and urine protein for 24 hours (UP24h) were measured using commercially available kits. Meanwhile, the activity of superoxide dismutase (SOD), content of malondialdehyde (MDA) in serum, activity of aldose reductase (AR) and the expression of AR mRNA and protein in kidney were detected by different methods. Results The results showed that oral administration of berberine (200 mg·kg^-1·d^-1) significantly ameliorated the ratio of kidney weight to body weight. Glomerular area, glomerular volume, FBG, BUN, Cr and UP24h were significantly decreased in the berberine treatment group compared with the diabetic model group (P〈0.05). Berberine treatment significantly increased serum SOD activity and decreased the content of MDA compared with diabetic model group (P 〈0.05). AR activity as well as the expression of AR mRNA and protein in the kidney was markedly decreased in the berberine treatment group compared with diabetic model group (P 〈0.05). Conclusion These results suggested that berberine could ameliorate renal dysfunction in DN rats through controlling blood glucose, reduction of oxidative stress and inhibition of the activation of the polyol pathway. 展开更多
关键词 BERBERINE diabetic nephropathy oxidative stress aldose reductase polyol pathway
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Epalrestat protects against diabetic peripheral neuropathy by alleviating oxidative stress and inhibiting polyol pathway 被引量:42
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作者 Qing-rong Li Zhuo Wang +8 位作者 Wei Zhou Shou-rui Fan Run Ma Li Xue Lu Yang Ya-shan Li Hong-li Tan Qi, ng-hua Shao Hong-ying Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第2期345-351,共7页
Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by... Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway. 展开更多
关键词 nerve regeneration peripheral nerve injury STREPTOZOTOCIN reactive oxygen species diabetic neuropathy oxidative stress aldosereductase antioxidant enzymes polyol pathway aldose reductase inhibitor superoxide dismutase CATALASE glutathione peroxidase rats NSFCgrant neural regeneration
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Effect of enalapril on plasma homocysteine levels in patients with essential hypertension 被引量:30
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作者 Fang-fang FAN Yong HUO +4 位作者 Xu WANG Xin XU Bin-yan WANG Xi-ping XU Jian-ping LI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2010年第8期583-591,共9页
Objective:To investigate the effect of enalapril on plasma homocysteine(Hcy) levels and the association of methylenetetrahydrofolate reductase(MTHFR) C677T polymorphism with the changes of Hcy levels in response to en... Objective:To investigate the effect of enalapril on plasma homocysteine(Hcy) levels and the association of methylenetetrahydrofolate reductase(MTHFR) C677T polymorphism with the changes of Hcy levels in response to enalapril among patients with essential hypertension.Methods:A total of 130 patients with mild-to-moderate essential hypertension were enrolled and enalapril was orally administered at a dose of 10 mg/d for eight weeks.Plasma Hcy levels were measured by denaturing high-performance liquid chromatography(DHPLC) at baseline and after eight weeks of treatment.Genotyping of MTHFR C677T polymorphism was performed by TaqMan probe technique.Results:Compared with baseline,plasma Hcy levels did not change significantly after eight weeks(P=0.81).Stratified by baseline Hcy levels,a significant increase in plasma Hcy levels(P=0.02) among those with Hcy <10 μmol/L was observed,in contrast to no significant changes in plasma Hcy levels(P=0.54) among those with Hcy ≥10 μmol/L.No significant association was observed between MTHFR C677T polymorphism and changes in Hcy levels in response to enalapril.Conclusions:Enalapril may cause an increase in plasma Hcy levels among the hypertensives with low baseline Hcy levels.There was no significant association between MTHFR C677T genotypes and changes in Hcy levels in response to enalapril among subjects with essential hypertension. 展开更多
关键词 Essential hypertension Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism ENALAPRIL HOMOCYSTEINE
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Nitrogen removal characteristics of heterotrophic nitrification-aerobic denitrification by Alcaligenes faecalis C16 被引量:28
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作者 Yuxiang Liu Yao Wang +2 位作者 Yi Li Hua An Yongkang Lv 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期827-834,共8页
Alcaligenes faecalis C16 was found to have the ability to heterotrophically nitrify and aerobically denitrify. In order to further understand its nitrogen removal ability and mechanism, the growth and ammonium removal... Alcaligenes faecalis C16 was found to have the ability to heterotrophically nitrify and aerobically denitrify. In order to further understand its nitrogen removal ability and mechanism, the growth and ammonium removal response were investigated at different C/N ratios and ammonium concentrations in the medium with citrate and acetate as carbon source separately. Furthermore, experiments of nitrogen sources, production of nitrogen gas and enzyme assay were conducted. Results show that the bacterium converts NH+4-N and produces NH2 OH during the growing phase and nitrite accumulation is its distinct metabolic feature. A. faecalis C16 is able to tolerate not only high ammonium concentration but also high C/N ratio, and the ammonium tolerance is associated with carbon source and C/N ratio. The nitrogen balance under different conditions shows that approximately28%–45% of the initial ammonium is assimilated into the cells, 44%–60% is denitrified and several percent is converted to nitrification products. A. faecalis C16 cannot utilize hydroxylamine, nitrite or nitrate as the sole nitrogen source for growth. However, nitrate can be used when ammonium is simultaneously present in the medium. A possible pathway for nitrogen removal by C16 is suggested. The preliminary enzyme assay provides more evidence for this nitrogen removal pathway. 展开更多
关键词 Heterotrophic nitrification-aerobic denitrification Alcaligenes faecalis Hydroxylamine oxidase Nitrate reductase Nitrite reductase
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Feedback regulation of cholesterol synthesis: sterol-accelerated ubiquitination and degradation of HMG CoA reductase 被引量:28
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作者 Russell A DeBose-Boyd 《Cell Research》 SCIE CAS CSCD 2008年第6期609-621,共13页
3-Hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase produces mevalonate, an important intermediate in the synthesis of cholesterol and essential nonsterol isoprenoids. The reductase is subject to an exorbitant... 3-Hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase produces mevalonate, an important intermediate in the synthesis of cholesterol and essential nonsterol isoprenoids. The reductase is subject to an exorbitant amount of feedback control through multiple mechanisms that are mediated by sterol and nonsterol end-products of mevalonate metabolism. Here, I will discuss recent advances that shed light on one mechanism for control of reductase, which involves rapid degradation of the enzyme. Accumulation of certain sterols triggers binding of reductase to endoplasmic reticulum (ER) membrane proteins called Insig-1 and Insig-2. Reductase-Insig binding results in recruitment of a membrane-associated ubiquitin ligase called gp78, which initiates ubiquitination of reductase. This ubiquitination is an obligatory reaction for recognition and degradation of reductase from ER membranes by cytosolic 26S proteasomes. Thus, sterol-accelerated degradation of reductase represents an example of how a general cellular process (ER-associated degradation) is used to control an important metabolic pathway (cholesterol synthesis). 展开更多
关键词 UBIQUITINATION cholesterol synthesis feedback regulation HMG CoA reductase STATIN Scap-SREBP Insig ERassociated degradation
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Aspirin and pravastatin reduce lectin-like oxidized low density lipoprotein receptor-1 expression, adhesion molecules and oxidative stress in human coronary artery endothelial cells 被引量:24
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作者 CHEN Jia-wei ZHOU Shi-bei TAN Zhi-ming 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第12期1553-1560,共8页
Background Oxidative stress and inflammation are important steps in the pathogenesis of atherosclerosis. We postulated that therapeutic concentrations of aspirin and pravastatin, especially in combination, may suppres... Background Oxidative stress and inflammation are important steps in the pathogenesis of atherosclerosis. We postulated that therapeutic concentrations of aspirin and pravastatin, especially in combination, may suppress oxidative stress and inflammation in endothelial cells, and this concept was examined in human coronary artery endothelial cells (HCAECs). Methods Human coronary artery endothelial cells were cultured and treated with oxidized-low density lipoprotein (ox-LDL, 60 ug/ml for 24 hours) alone, or pre-treated with aspirin (1, 2 or 5 mmol/L), pravastatin (1, 5 or 10 umol/L) or their combination (1 mmol/L aspirin and 5umol/L pravastatin), followed by ox-LDL treatment. After respective treatment, superoxide anion production, p38 mitogen activated protein kinase and transcription factor NF-KB activation, protein expression of lectin-like ox-LDL receptor-1 (LOX-1) and adhesion molecules, and monocyte adhesion were measured. Results Ox-LDL treatment greatly elicited its receptor LOX-1 expression, superoxide anion production and inflammatory response, which were minimally affected by low concentration of aspirin (1 mmol/L) or pravastatin (5umol/L), but were markedly decreased by their combination. Activation of p38 mitogen activated protein kinase and NF-KB, the expression of intercellular adhesion molecule-1 and monocyte chemotactic protein-I, which were only mildly affected by aspirin or pravastatin alone, were significantly attenuated by their combination. As a consequence, monocyte adhesion to endothelial cells was markedly attenuated by the combination of the two agents. Well-known anti-oxidants a-tocopherol and y-tocopherol had similar inhibitory effects on ox-LDL-mediated oxidative stress and LOX-1 expression as well as monocyte adhesion as did the combination of aspirin and pravastatin. Conclusions These studies point to a positive interaction between aspirin and pravastatin with regard to endothelial bioloqy. Anti-oxidant and subsequent anti-inflammatory effect may be on 展开更多
关键词 ASPIRIN endothelial dysfunction HMG CoA reductase inhibitor INFLAMMATION oxidative stress
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六价铬还原细菌Bacillus cereus S5.4还原机理及酶学性质研究 被引量:24
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作者 肖伟 王磊 +2 位作者 李倬锴 张思维 任大明 《环境科学》 EI CAS CSCD 北大核心 2008年第3期751-755,共5页
从宝钢电镀污泥中分离得到1株六价铬还原细菌Bacillus cereus S5.4,在液体LB培养基中培养72 h完全还原2 mmol/LCr^6+.测定该菌株六价铬还原后细胞内外六价铬和总铬浓度,检测细胞各组分六价铬还原能力,并结合扫描电镜分析六价铬还原前... 从宝钢电镀污泥中分离得到1株六价铬还原细菌Bacillus cereus S5.4,在液体LB培养基中培养72 h完全还原2 mmol/LCr^6+.测定该菌株六价铬还原后细胞内外六价铬和总铬浓度,检测细胞各组分六价铬还原能力,并结合扫描电镜分析六价铬还原前后细胞形态的变化.结果表明,细菌的细胞壁膜能阻止六价铬进入细胞,是六价铬发生还原的主要场所,其通透性的改变将影响六价铬还原酶的作用;该菌株六价铬还原酶为非分泌型,在细菌细胞内侧发生作用.测定六价铬还原酶活性和稳定性:其最适温度范围25-37℃,最适pH 7,Cu^2+有增强六价铬还原酶活性的作用;在37℃,该菌株六价铬还原酶Km为125.61μmol/L,Vmax为7.68 nmol/(min·mg). 展开更多
关键词 Bacilluscereus 六价铬 还原酶 酶动力学曲线
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细胞色素P450酶的结构、功能与应用研究进展 被引量:24
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作者 宋展 高鑫 +2 位作者 吴冕 路福平 秦慧民 《微生物学通报》 CAS CSCD 北大核心 2020年第7期2245-2254,共10页
细胞色素P450(cytochrome P450,CYP)酶是广泛存在于微生物、动植物及人体中与膜结合的血红蛋白类酶,具有氧化、环氧化、羟化、去甲基化等多种生物催化活性。CYP酶在药物、类固醇、脂溶性维生素和许多其他类型化学物质的代谢中具有重要作... 细胞色素P450(cytochrome P450,CYP)酶是广泛存在于微生物、动植物及人体中与膜结合的血红蛋白类酶,具有氧化、环氧化、羟化、去甲基化等多种生物催化活性。CYP酶在药物、类固醇、脂溶性维生素和许多其他类型化学物质的代谢中具有重要作用,其在异源物质的解毒、药物相互作用和内分泌功能等领域的研究是热点问题。本综述对CYP的结构、功能、临床应用与开发前景进行了概述,并对其最新的研究现状和发展前景进行探讨。 展开更多
关键词 细胞色素P450 还原酶 结构 功能 遗传多态性
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Impacts of Elevated CO2 Concentration on Biochemical Composition, Carbonic Anhydrase, and Nitrate Reductase Activity of Freshwater Green Algae 被引量:21
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作者 Jian-RongXIA Kun-ShanGAO 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2005年第6期668-675,共8页
: To investigate the biochemical response of freshwater green algae to elevated CO2 concentrations, Chlorella pyrenoidosa Chick and Chlamydomonas reinhardtii Dang cells were cultured at different CO2 concentrations wi... : To investigate the biochemical response of freshwater green algae to elevated CO2 concentrations, Chlorella pyrenoidosa Chick and Chlamydomonas reinhardtii Dang cells were cultured at different CO2 concentrations within the range 3-186 ümol/L and the biochemical composition, carbonic anhydrase (CA), and nitrate reductase activities of the cells were investigated. Chlorophylls (Chl), carotenoids, carbonhydrate, and protein contents were enhanced to varying extents with increasing CO2 concentration from 3-186 ümol/L. The CO2 enrichment significantly increased the Chl a/Chl b ratio in Chlorella pyrenoidosa, but not in Chlamydomonas reinhardtii. The CO2 concentration had significant effects on CA and nitrate reductase activity. Elevating CO2 concentration to 186 ümol/L caused a decline in intracellular and extracellullar CA activity. Nitrate reductase activity, under either light or dark conditions, in C. reinhardtii and C. pyrenoidosa was also significantly decreased with CO2 enrichment. From this study, it can be concluded that CO2 enrichment can affect biochemical composition, CA, and nitrate reductase activity, and that the biochemical response was species dependent. 展开更多
关键词 carbonic anhydrase Chlamydomonas reinhardtii Chlorella pyrenoidosa CO2 nitrate reductase
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Single nucleotide polymorphism C677T in the methylenetetrahydrofolate reductase gene might be a genetic risk factor for infertility for Chinese men with azoospermia or severe oligozoospermia 被引量:21
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作者 Zhou-Cun A Yuan Yang +2 位作者 Si-Zhong Zhang Na Li Wei Zhang 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第1期57-62,共6页
Aim: To analyze the distribution of the single nucleotide polymorphism (SNP) C677T in the methylenetetrahydrofolate reductase (MTHFR) gene in 355 infertile Chinese patients with idiopathic azoospermia or severe o... Aim: To analyze the distribution of the single nucleotide polymorphism (SNP) C677T in the methylenetetrahydrofolate reductase (MTHFR) gene in 355 infertile Chinese patients with idiopathic azoospermia or severe oligozoospermia and 252 fertile Chinese men as controls to explore the possible association of the SNP and male infertility. Methods: Using the polymerase chain reaction (PCR)-restriction fragment length polymorphism technique, the allele and genotype distribution of SNP C677T in the MTHFR gene were investigated in both patients and controls. Results: The frequencies of allele T (40.9% vs 30.4%, P = 0.002, odds ration [OR] = 1.58, 95% confidence interval [CI]: 1.24-2.02) and mutant homozygote (TT) (18.3% vs. 11.5%, P = 0.023, OR = 1.72, 95% CI: 1.07-2.76) as well as carrier with allele (TT + CT) (63.4% vs. 49.2%, P = 0.0005, OR = 1.79, 95% CI: 1.29-2.48) in infertile patients were significantly higher than those in controls. After patient stratification, the significant differences in distribution of the SNP between each patient subgroup and control group still remained. Conclusion: Our findings indicate that there is an association of SNP C677T in the MTHFR gene with male infertility, suggesting that this polymorphism might be a genetic risk factor for male infertility in Chinese men. 展开更多
关键词 male infertility methylenetetrahydrofolate reductase gene single nucleotide polymorphism C677T
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The Simultaneous Repression Of CCR and CAD, Two Enzymes of the Lignin Biosynthetic Pathway, Results in Sterility and Dwarfism in Arabidopsis thaliana 被引量:20
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作者 Johanne Thevenin Brigitte Pollet +5 位作者 Bruno Letarnec Luc Saulnier Lionel Gissot Alessandra Maia-Grondard Catherine Lapierre Lise Jouanin 《Molecular Plant》 SCIE CAS CSCD 2011年第1期70-82,共13页
Cinnamoyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) catalyze the last steps of mono- lignol biosynthesis. In Arabidopsis, one CCR gene (CCR1, Atlg15950) and two CAD genes (CAD C At3g19450 and... Cinnamoyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) catalyze the last steps of mono- lignol biosynthesis. In Arabidopsis, one CCR gene (CCR1, Atlg15950) and two CAD genes (CAD C At3g19450 and CAD D At4g34230) are involved in this pathway. A triple cad c cad d ccrl mutant, named ccc, was obtained. This mutant displays a severe dwarf phenotype and male sterility. The lignin content in ccc mature stems is reduced to 50% of the wild-type level. In addition, stem lignin structure is severely affected, as shown by the dramatic enrichment in resistant inter-unit bonds and incorporation into the polymer of monolignol precursors such as coniferaldehyde, sinapaldehyde, and ferulic acid. Male sterility is due to the lack of lignification in the anther endothecium, which causes the failure of anther de- hiscence and of pollen release. The cc~ hypolignified stems accumulate higher amounts of flavonol glycosides, sinapoyl malate and feruloyl malate, which suggests a redirection of the phenolic pathway. Therefore, the absence of CAD and CCR, key enzymes of the monolignol pathway, has more severe consequences on the phenotype than the individual absence of each of them. Induction of another CCR (CCR2, Atlg80820) and another CAD (CAD1, At4g39330) does not compensate the absence of the main CCR and CAD activities. This lack of CCR and CAD activities not only impacts lignification, but also severely affects the development of the plants. These consequences must be carefully considered when trying to reduce the lignin content of plants in order to facilitate the lignocellulose-to-bioethanol conversion process. 展开更多
关键词 Arabidopsis auxin Cinnamyl Alcohol Dehydrogenase (CAD) Cinnamoyl CoA reductase (CCR) cell wall DWARFISM LIGNINS phenolics sterility.
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Efficacy of epalrestat plus α-lipoic acid combination therapy versus monotherapy in patients with diabetic peripheral neuropathy: a meta-analysis of 20 randomized controlled trials 被引量:20
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作者 Ming Zhao Jia-Yi Chen +3 位作者 Yu-Dong Chu Ya-Bin Zhu Lin Luo Shi-Zhong Bu 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第6期1087-1095,共9页
OBJECTIVE: To evaluate the efficacy of α-lipoic acid(ALA) plus epalrestat combination therapy in the treatment of diabetic peripheral neuropathy(DPN). DATA SOURCES: The electronic databases of Pub Med, Medline,... OBJECTIVE: To evaluate the efficacy of α-lipoic acid(ALA) plus epalrestat combination therapy in the treatment of diabetic peripheral neuropathy(DPN). DATA SOURCES: The electronic databases of Pub Med, Medline, Embase, the Cochrane Library, the Chinese National Knowledge Infrastructure, the Wanfang Database and the Chinese Biomedical Database were used to retrieve relevant studies without language restrictions. The search was conducted from the inception of each database to 7 October 2016. The key terms were(diabetic peripheral neuropathy or diabetic neuropathy or DPN) AND(α-lipoic acid or lipoic acid or thioctic acid) AND epalrestat. DATA SELECTION: All of the eligible studies met the following inclusion criteria:(1) Randomized controlled trials that compared efficacy and safety of epalrestat plus ALA combination therapy versus epalrestat or ALA monotherapy in patients with DPN.(2) The minimum duration of treatment was 2 weeks.(3) The DPN patients were diagnosed using the World Health Organization standardized type 2 diabetes mellitus and DPN criteria.(4) Studies contained at least one measure that could reflect the efficacy of the drug and nerve conduction velocities. Studies in which the control group used epalrestat or ALA combined with other drugs were excluded. Statistical analyses were performed using STATA software for meta-analysis. OUTCOME MEASURES: The primary outcomes were the therapeutic efficacy, median motor nerve conduction velocity(MNCV), median sensory nerve conduction velocity(SNCV), peroneal MNCV and peroneal SNCV.RESULTS: Twenty studies with 1894 DPN patients were included, including 864 patients in the ALA plus epalrestat group, 473 in the ALA group and 557 in the epalrestat group. The efficacy of ALA plus epalrestat combination therapy was superior to ALA and epalrestat monotherapies(RR = 1.29, 95% CI: 1.21–1.38; RR = 1.43, 95% CI: 1.34–1.54, respectively). ALA plus epalrestat combination therapy also significantly improved m 展开更多
关键词 nerve regeneration ANTIOXIDANT aldose reductase inhibitor diabetic complication DIABETES combination therapy nerve conduction velocity nerve electrophysiology peripheral nerve injury neural regeneration
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Cloning and functional characterization of two cDNAs encoding NADPH-dependent 3-ketoacyl-CoA reductased from developing cotton fibers 被引量:15
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作者 YongMeiQIN FrancoisMAPUJOL +5 位作者 YongHuiSHI JianXunFENG YiMingLIU AlexanderJKASTANIOTIS JKalervoHILTUNEN YuXianZHU 《Cell Research》 SCIE CAS CSCD 2005年第6期465-473,共9页
Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoA... Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoAreductases that catalyze the second step in fatty acid elongation, were isolated from developing cotton fibers. GhKCR1and 2 contain open reading frames of 963 bp and 924 bp encoding proteins of 320 and 307 amino acid residues,respectively. Quantatitive RT-PCR analysis showed that both these genes were highly preferentially expressed duringthe cotton fiber elongation period with much lower levels recovered from roots, stems and leaves. GhKCR1 and 2showed 30%-32% identity to Saccharomyces cerevisiae Ybr159p at the deduced amino acid level. These cotton cDNAswere cloned and expressed in yeast haploid ybr159w? mutant that was deficient in 3-ketoacyl-CoA reductase activity.Wild-type growth rate was restored in ybr159w? cells that expressed either GhKCR1 or 2. Further analysis showed thatGhKCR1 and 2 were co-sedimented within the membranous pellet fraction after high-speed centrifugation, similar to theyeast endoplasmic reticulum marker ScKar2p. Both GhKCR(s) showed NADPH-dependent 3-ketoacyl-CoA reductaseactivity in an in vitro assay system using palmitoyl-CoA and malonyl-CoA as substrates. Our results suggest thatGhKCR1 and 2 are functional orthologues of ScYbr159p. 展开更多
关键词 very-long-chain fatty acids endoplasmic reticulum fatty acid elongation system 3-ketoacyl-CoA reductase Gossypium hirsutum short-chain alcohol dehydrogenase/reductase protein family.
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Effect of Salicylic Acid on Salinity-induced Changes in Brassica juncea 被引量:16
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作者 Mohammad Yusuf Syed Aiman Hasan +3 位作者 Barket Ali Shamsul Hayat Qazi Fariduddin Aqil Ahmad 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第9期1096-1102,共7页
Seeds of Indian mustard (Brassicajuncea (L.) Czern. et Coss.) were exposed to 0, 50, 100 and 150 mmol/L NaCI for 8 h and seeds were sown in an earthen pot. These stressed seedlings were subsequently sprayed with 1... Seeds of Indian mustard (Brassicajuncea (L.) Czern. et Coss.) were exposed to 0, 50, 100 and 150 mmol/L NaCI for 8 h and seeds were sown in an earthen pot. These stressed seedlings were subsequently sprayed with 10μmol/L salicylic acid (SA) at 30 d and were sampled at 60 d to assess the changes in growth, photosynthesis and antioxidant enzymes. The seedlings raised from the seeds treated with NaCI had significantly reduced growth and the activities of carbonic anhydrase, nitrate reductase and photosynthesis, and the decrease was proportional to the increase in NaCI concentration. However, the antioxidant enzymes (catalase, peroxidase and superoxide dismutase) and proline content was enhanced in response to NaCI and/or SA treatment, where their interaction had an additive effect. Moreover, the toxic effects generated by the lower concentration of NaCI (50 mmol/L) were completely overcome by the application of SA. It was, therefore, concluded that SA ameliorated the stress generated by NaCl through the alleviated antioxidant system. 展开更多
关键词 carbonic anhydrase CATALASE MUSTARD net photosynthetic rate nitrate reductase PEROXIDASE salicylic acid SALINITY superoxidedismutase.
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Influences of Mo on Nitrate Reductase, Glutamine Synthetase and Nitrogen Accumulation and Utilization in Mo-Efficient and Mo-Inefficient Winter Wheat Cultivars 被引量:17
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作者 YU Min HU Cheng-xiao +1 位作者 SUN Xue-cheng WANG Yun-hua 《Agricultural Sciences in China》 CAS CSCD 2010年第3期355-361,共7页
The objective is to study whether the accumulation and utilization of plant N are controlled by Mo status in winter wheat cultivars. Mo-efficient cultivar 97003 (eft) and Mo-inefficient cultivar 97014 (ineff) were... The objective is to study whether the accumulation and utilization of plant N are controlled by Mo status in winter wheat cultivars. Mo-efficient cultivar 97003 (eft) and Mo-inefficient cultivar 97014 (ineff) were grown in severely Mo-deficient acidic soil (Tamm-reagent-extractable Mo 0.112 mg kg^-1) with (+Mo) and without (-Mo) the application of 0.13 mg kg^-1 Mo. The accumulation and use efficiency of plant total N were significantly higher in +Mo than that in -Mo and in eft than that in ineff under Mo deficiency. N use efficiency was remarkably higher in maturity but it was forwarded to jointing stage after Mo supply, thus indicating that Mo supply promoted the N use efficiency besides N uptake and eff was efficient in N uptake and utilization. The overall activity of nitrate reductase (NR, EC 1.6.6.1) was significantly higher in +Mo than in -Mo and ratio of +Mo/-Mo was even to 14.8 at filleting stage for ineff. Activity of glutamine synthetase (GS, EC 6.3.1.2) was significantly lower in +Mo than in -Mo. Concentration of nitrate and glutamate were also significantly lower in +Mo than in -Mo, thus provided evidences for enhancing N use efficiency by Mo supply. Activities of NR and GS were significantly higher and concentrations of nitrate and glutamate were significantly lower in eff than ineff under Mo deficiency, thus indicated eff was more efficient in N reduction and utilization. It is therefore concluded that Mo could promote N accumulation and utilization in winter wheat which was directly related to NR and feedback regulated by GS. Higher Mo status also results in higher accumulation and utilization of plant N in eft. 展开更多
关键词 winter wheat MO N accumulation N use efficiency nitrate reductase glutamine synthetase
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Diabetes mellitus:An overview on its pharmacological aspects and reported medicinal plants having antidiabetic activity 被引量:17
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作者 Patel DK Kumar R +1 位作者 Laloo D Hemalatha S 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第5期411-420,共10页
Diabetes mellitus is not a single disease but is a group of metabolic disorders affecting a huge numlier of population in the world.It is mainly characterized by chronic hyperglycemia,resulting from defects in insulin... Diabetes mellitus is not a single disease but is a group of metabolic disorders affecting a huge numlier of population in the world.It is mainly characterized by chronic hyperglycemia,resulting from defects in insulin secretion or insulin action.It is predicated that the number of diabetes person in the world could reach upto 366 million by the year 2030.Even though the cases of diabetes are increasing day by day,except insulin and oral hypoglycemic drugs no other way of treatment has been successfully developed so far.Thus,the objective of the present review is to provide an insight over the pathophysiological and etiological aspects of diabetes mellitus along with the remedies available for this metabolic disorder.The review also contains brief idea about diabetes mellitus and the experimental screening model with their relevant mechanism and significance mainly used nowadays.Alloxan and streptozotocin are mainly used for evaluating the antidiabetic activity of a particular drug.This review contain list of medicinal plants which have been tested for their antidiabetic activity in the alloxan induced diabetic rat model.From the available data in the literature,it was found that plant having antidiabetic activity is mainly due to the presence of the secondary metabolite.Thus,the information provided in this review will help the researchers for the development of an alternative methods rather than insidin and oral hypoglycemic agents for the treatment of diabetes niellitus,which will minimize the complication associated with the diabetes and related disorder. 展开更多
关键词 ALDOSE reductase ALLOXAN Antioxidant Diabetes mellitus Insulin PHYTOCONSTITUENTS STREPTOZOTOCIN Oral HYPOGLYCEMIC agents
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高铁肌红蛋白还原酶活力与肉色稳定性关系的研究 被引量:18
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作者 王永林 赵建生 《肉类研究》 2010年第3期21-25,共5页
本文通过对冷却肉采用CO气调包装和真空包装在4±1℃贮藏,研究了高铁肌红蛋白还原酶活性变化规律及与肉色稳定性之间的关系,并研究了不同实验条件下高铁肌红蛋白还原酶的特性。结果表明:高铁肌红蛋白还原酶在宰后2周内仍然存在较高... 本文通过对冷却肉采用CO气调包装和真空包装在4±1℃贮藏,研究了高铁肌红蛋白还原酶活性变化规律及与肉色稳定性之间的关系,并研究了不同实验条件下高铁肌红蛋白还原酶的特性。结果表明:高铁肌红蛋白还原酶在宰后2周内仍然存在较高活性,其活性作用可使肉中的高铁肌红蛋白含量持续下降,对肉的色泽稳定起着重要的作用;在pH6.5,酶的活性最大,温度10℃时,该酶活性依然很好,可通过创造无氧、pH6.5左右的环境,使该酶发挥活性来调节肉的颜色。 展开更多
关键词 冷却肉 肉色 高铁肌红蛋白 还原酶
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Fluvastatin attenuates myocardial interstitial fibrosis and cardiac dysfunction in diabetic rats by inhibiting over-expression of connective tissue growth factor 被引量:15
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作者 DAI Qi-ming LU Jing LIU Nai-feng 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第1期89-94,共6页
Background Diabetic myocardiopathy is characterized by myocardial interstitial fibrosis and cardiac dysfunction. Statins were found to exert protective effects on cardiovascular disease by suppressing activation of sm... Background Diabetic myocardiopathy is characterized by myocardial interstitial fibrosis and cardiac dysfunction. Statins were found to exert protective effects on cardiovascular disease by suppressing activation of small G proteins, independently of their lipid-lowering effect. The study investigated the effect of fluvastatin on myocardial interstitial fibrosis, cardiac function and mechanism of its action in diabetic rats. Methods Twenty-four male SD rats were randomly assigned to 3 groups: control rats (n=-8), streptozotocin (STZ)-induced diabetic rats (n=8), and diabetic rats treated with fluvastatin (administered fluvastatin orally, 10 mg/kg body weight per day, n=-8). Twelve weeks later, miniature cardiac catheter was inserted into the left ventricle to conduct hemodynamic examination. Then myocardium tissues were collected, collagen content was detected by picro-sirius red staining, real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of connective tissue growth factor (CTGF), and Western blotting was used to detect the protein expression of CTGF. Rho activity was determined by pull-down assay. Results After 12 weeks, the left ventricular systolic pressure (LVSP) and maximum rate of left ventricular (LV) pressure rise and fall (+dP/dt max and -dP/dt max) were significantly lower and left ventricular end diastolic pressure (LVEDP) was higher in the diabetic rats than those in the control rats (P 〈0.01). Moreover, in LV myocardial tissue of diabetic rats the collagen content, fibronectin, mRNA and protein expression of CTGF and the activity of RhoA were all significantly increased compared with the control rats (P 〈0.01). Administration of fluvastain obviously improved the cardiac function of diabetic rats, attenuated fibronectin expression, mRNA and protein expression of CTGF and the activity of RhoA in LV myocardium of diabetic rats. Conclusions Fluvastatin attenuates cardiac dysfunction 展开更多
关键词 HMG-CoA reductase inhibitors diabetes mellitus myocardial fibrosis heart failure Rho/Rho-kinase
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RRM1 gene expression in peripheral blood is predictive of shorter survival in Chinese patients with advanced non-small-cell lung cancer treated by gemcitabine and platinum 被引量:14
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作者 Lin-run WANG Guo-bing ZHANG +5 位作者 Jian CHEN Jun LI Ming-wei LI Nong XU Yang WANG Jian-zhong SHEN TU4 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第3期174-179,共6页
Objective:To evaluate the predictive values of gene expressions of ribonucleotide reductase M1(RRM1) and breast cancer susceptibility gene 1(BRCA1) in peripheral blood from Chinese patients with non-small-cell lung ca... Objective:To evaluate the predictive values of gene expressions of ribonucleotide reductase M1(RRM1) and breast cancer susceptibility gene 1(BRCA1) in peripheral blood from Chinese patients with non-small-cell lung cancer(NSCLC) treated with gemcitabine plus platinum.Methods:Forty Chinese patients with advanced NSCLC were recruited and received gemcitabine 1200 mg/m 2 on Days 1 and 8 plus carboplatin AUC 5 on Day 1.RRM1 and BRCA1 expression levels in peripheral blood were detected by quantitative reverse transcription-polymerase chain reaction(RT-PCR) .Kaplan-Meier survival curve and log-rank test were performed to evaluate the correlation between gene expression and overall survival for these subjects.Results:No correlation was observed between gene expression of RRM1 and that of BRCA1(P>0.05) ,but there was a strong correlation between the expression of RRM1 and the response to chemotherapy(P=0.003) .Subjects with low RRM1 expression levels in peripheral blood had longer sur-vival time than those with high RRM1 expression levels(16.95 vs.12.76 months,log-rank 3.989,P=0.046) .However,no significant association between BRCA1 expression levels and survival time was found(16.80 vs.13.77 months,log-rank 0.830,P=0.362) .Conclusions:Patients with low RRM1 expression levels in peripheral blood have a greater response to chemotherapy and longer survival time.Advanced NSCLC patients with low RRM1 expression levels may benefit from gemcitabine plus platinum therapy.RRM1 mRNA expression in peripheral blood could be used to predict the prognosis of NSCLC treated by gemcitabine and platinum. 展开更多
关键词 GEMCITABINE Non-small-ce Ribonucleotide reductase M1 (RRM1) Breast cancer susceptibility gene 1 (BRCA1) ung cancer (NSCLC) Gene expression
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Plasma Homocysteine and Gene Polymorphisms Associated with the Risk of Hyperlipidemia in Northern Chinese Subjects 被引量:14
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作者 LEI HUANG XIAO-MING SONG WEN-LI ZHU YONG LI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第6期514-520,共7页
Objective To examine the relationship between occurrence of hyperlipidemia, plasma homocysteine and polymorphisms of methylenetetra hydrofolate reductase (MTHFR) gene and methionine synthase (MS) gene. Methods A t... Objective To examine the relationship between occurrence of hyperlipidemia, plasma homocysteine and polymorphisms of methylenetetra hydrofolate reductase (MTHFR) gene and methionine synthase (MS) gene. Methods A total of 192 hyperlipidemia patients were selected and divided into hypercholesterolemia group, hypertriglyceridemia group, and combined hyperlipidemia group. Another 208 normal individuals were selected as control. Total plasma homocysteine (tHcy) concentration was measured by high-performance liquid chromatography (HPLC). Lipid profiles were measured for all subjects The polymorphisms of MTHFR gene C677T and MS gene A2756G were analyzed by PCR-RFLP. Results The tHcy concentration in the combined hyperlipidemia patients was significantly higher than that in the control (15.95μmol/L vs 13.43 μmol/L, P〈0.05). The prevalence of hyperhomocysteinemia (HHcy) in the combined hyperlipidemia group was significantly higher than that in the control (42.2% vs 23.0%, P=0.015), with the odds ratio (OR) of 3.339 (95%CI: 1.260-8.849). The hyperlipidemia patients with HHcy had a higher concentration of total cholesterol (TC) than that in the normal tHcy patients (5.67±0.95 mmol/L vs 5.47±0.92 retool/L, P=0.034). There was no significant difference in genotype or allele frequencies of MTHFR C677T between the hyperlipidemic and control groups. The hyperlipidemia patients with MTHFR CT/TT genotype had a higher concentration of triglyceride (TG) than those with CC genotype (2.24±1.75 mmol/L vs 1.87±0.95 mmol/L, P〈0.05). Individuals with CT/TT genotype had a higher concentration of tHcy than those with 677CC genotype both in the hyperlipidemia group (12.61±1.24μmol/L vs 11.20±1.37 μmol/L, P〈0.05) and in the control group (14.04±1.48 μmol/L vs 12.61±1.24 μmol/L, P〈0.05). The percentage of MS 2756 GG/AG genotype in the combined hyperlipidemia group was significantly higher than that in the control (26.7% vs 13.0%, P=0.012), with the OR of 3. 展开更多
关键词 Methylenetetra hydrofolate reductase Methionine synthase Gene polymorphism HOMOCYSTEINE HYPERLIPIDEMIA
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