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A high-quality genome of Actinidia eriantha provides new insight into ascorbic acid regulation
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作者 LIAO Guang-lian HUANG Chun-hui +4 位作者 JIA Dong-feng ZHONG Min TAO Jun-jie QU Xue-yan XU Xiao-biao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第11期3244-3255,共12页
Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecula... Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics,metabolomics and transcriptomics.We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps.The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb.Among them,24 of the pseudochromosomes were obtained directly from telomere-to-telomere.The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively.Subsequently, 61 metabolites and 2 092genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively.AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development,suggesting its crucial role in the regulation of AsA.Furthermore,the AsA contents are highly associated with ascorbate peroxidase genes.The genome obtained in this study provides genomic resources for the genetic and breeding research ofA. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit. 展开更多
关键词 Actinidia eriantha ascorbic acid non-targeted metabolome gapless genome TRANSCRIPTOME
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Appraisal of Improvement in Physiological and Metabolic Processes by Exogenously Applied Natural and Synthetic Ascorbic Acid in Okra(Abelmoschus esculentus L.)Fruit Subjected to Water Deficit Stress
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作者 Muhammad Younis Nudrat Aisha Akram +1 位作者 Arafat Abdel Hamed Abdel Latef Muhammad Ashraf 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第10期2761-2784,共24页
To counteract the effects of drought stress,scientists have adopted several approaches including the use of different chemicals both inorganic and organic,which is contemplated as a highly efficient and cost-effective... To counteract the effects of drought stress,scientists have adopted several approaches including the use of different chemicals both inorganic and organic,which is contemplated as a highly efficient and cost-effective shot-gun approach.Ascorbic acid(AsA)is a potential organic substance,which widely occurs in plants,and is considered to be an effective antioxidant to counteract reactive oxygen species(ROS).Thus,a pot experiment was performed to assess the relative mitigating impacts of synthetic AsA and naturally occurring AsA in the form of lemon juice(LJ)and orange juice(OJ)on two cultivars of okra(Abelmoschus esculentus L.)namely Sabz Pari and Bhindi Sanwali under varying water deficit conditions.After 30 days of seed germination,okra seedlings were subjected to different irrigation regimes,i.e.,water deficit stress[(65%and 50%F.C.)and control conditions(100%F.C.)].Different levels of AsA[control(no spray),14 mg L^(−1)LJ,24 mg L^(−1)OJ and 150 mg L^(−1)AsA]obtained from different sources were applied as a foliar spray to control and water-stressed plants.Drought stress prominently reduced plant growth and yield attributes of the okra cultivars.Water-deficit conditions(65%and 50%F.C.)substantially decreased the fruit chlorophyll(a,b)pigments and the activity of superoxide dismutase(SOD)enzyme,while an increase was observed in the contents of fruit’s hydrogen peroxide(H_(2)O_(2)),malondialdehyde(MDA),total phenolics,total soluble sugars,AsA,and total soluble proteins.Drought stress also increased the activities of antioxidant enzymes like peroxidase(POD)and catalase(CAT).However,plant growth and yield attributes,fruit chlorophyll pigments,total phenolics,total soluble sugars,total free amino acids,total soluble proteins,AsA,GB,H_(2)O_(2),and the activities of antioxidant enzymes(POD and CAT)were increased by the AsA exogenous treatment in both okra cultivars under water deficit and control conditions.Overall,LJ and OJ were more effective than the synthetic AsA in upregulating the physiological and metabolic processes of okra plants.So,cost-effective as well as multi-nutrient natural sources of AsA could be suggested for alleviating the harmful effects of water deficit stress on plants. 展开更多
关键词 OKRA ascorbic acid lemon juice orange juice drought tolerance
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Ascorbic acid accelerates Wallerian degeneration after peripheral nerve injury 被引量:6
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作者 Lixia Li Yizhou Xu +5 位作者 Xianghai Wang Jingmin Liu Xiaofang Hu Dandan Tan Zhenlin Li Jiasong Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第6期1078-1085,共8页
Wallerian degeneration occurs after peripheral nerve injury and provides a beneficial microenvironment for nerve regeneration.Our previous study demonstrated that ascorbic acid promotes peripheral nerve regeneration,p... Wallerian degeneration occurs after peripheral nerve injury and provides a beneficial microenvironment for nerve regeneration.Our previous study demonstrated that ascorbic acid promotes peripheral nerve regeneration,possibly through promoting Schwann cell proliferation and phagocytosis and enhancing macrophage proliferation,migration,and phagocytosis.Because Schwann cells and macrophages are the main cells involved in Wallerian degeneration,we speculated that ascorbic acid may accelerate this degenerative process.To test this hypothesis,400 mg/kg ascorbic acid was administered intragastrically immediately after sciatic nerve transection,and 200 mg/kg ascorbic acid was then administered intragastrically every day.In addition,rat sciatic nerve explants were treated with 200μM ascorbic acid.Ascorbic acid significantly accelerated the degradation of myelin basic protein-positive myelin and neurofilament 200-positive axons in both the transected nerves and nerve explants.Furthermore,ascorbic acid inhibited myelin-associated glycoprotein expression,increased c-Jun expression in Schwann cells,and increased both the number of macrophages and the amount of myelin fragments in the macrophages.These findings suggest that ascorbic acid accelerates Wallerian degeneration by accelerating the degeneration of axons and myelin in the injured nerve,promoting the dedifferentiation of Schwann cells,and enhancing macrophage recruitment and phagocytosis.The study was approved by the Southern Medical University Animal Care and Use Committee(approval No.SMU-L2015081)on October 15,2015. 展开更多
关键词 ascorbic acid AXON MACROPHAGE MYELIN peripheral nerve injury PHAGOCYTOSIS Schwann cell Wallerian degeneration
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Formation of a cerium conversion coating on magnesium alloy using ascorbic acid as additive.Characterisation and anticorrosive properties of the formed films 被引量:7
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作者 A.P.Loperena I.L.Lehr S.B.Saidman 《Journal of Magnesium and Alloys》 SCIE EI CAS 2016年第4期278-285,共8页
Cerium-based conversion coatings were formed on AZ91D magnesium alloy by immersion of the substrate in solutions containing Ce(NO_(3))_(3),H_(2)O_(2) and ascorbic acid(HAsc).The characterisation of the films was perfo... Cerium-based conversion coatings were formed on AZ91D magnesium alloy by immersion of the substrate in solutions containing Ce(NO_(3))_(3),H_(2)O_(2) and ascorbic acid(HAsc).The characterisation of the films was performed by electrochemical and surface analysis techniques such as SEM,EDS,X-ray diffraction and X-ray photoelectron spectroscopy(XPS).The degree of corrosion protection achieved was evaluated in simulated physiological solution by the open circuit potential monitoring,polarisation techniques and electrochemical impedance spectroscopy(EIS).The presence of HAsc in the conversion solution causes changes in the morphology,adherence and anticorrosive performance of the films.The improvement in the corrosion resistance is closely associated with the corrosion inhibition properties of HAsc. 展开更多
关键词 Cerium coatings AZ91D alloy ascorbic acid Anticorrosive properties
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Chromium-induced membrane damage: protective role of ascorbic acid 被引量:1
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作者 Sankar Kumar Dey, Prasunpriya Nayak, Somenath Roy * (Department of Human Physiology with Community Health, Vidyasagar University, Midnapore 721 102, West Bengal, India 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第3期272-275,共4页
Importance of chromium as environmental toxicant is largely due to impact on the body to produce cellular toxicity. The impact of chromium and their supplementation with ascorbic acid was studied on plasma membrane of... Importance of chromium as environmental toxicant is largely due to impact on the body to produce cellular toxicity. The impact of chromium and their supplementation with ascorbic acid was studied on plasma membrane of liver and kidney in male Wistar rats (80-100g body weight). It has been observed that the intoxication with chromium (i.p.) at the dose of 0.8 mg/100g body weight per day for a period of 28 days causes significant increase in the level of cholesterol and decrease in the level of phospholipid of both liver and kidney. The alkaline phosphatase, total ATPase and Na\++\|K\++\|ATPase activities were significantly decreased in both liver and kidney after chromium treatment, except total ATPase activity of kidney. It is suggested that chromium exposure at the present dose and duration induce for the alterations of structure and function of both liver and kidney plasma membrane. Ascorbic acid (i.p. at the dose of 0.5 mg/100g body weight per day for period of 28 days) supplementation can reduce these structural changes in the plasma membrane of liver and kidney. But the functional changes can not be completely replenished by the ascorbic acid supplementation in response to chromium exposure. So it is also suggested that ascorbic acid (nutritional antioxidant) is useful free radical scavenger to restrain the chromium induced membrane damage. 展开更多
关键词 CHROMIUM LIVER KIDNEY MEMBRANE ascorbic acid
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Overoxidized poly(3,4-ethylenedioxythiophene)-gold nanoparticles-graphene-modified electrode for the simultaneous detection of dopamine and uric acid in the presence of ascorbic acid 被引量:1
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作者 Junqiang Pan Mei Liu +2 位作者 Dandan Li Haonan Zheng Dongdong Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第6期699-708,共10页
An innovative,ternary nanocomposite composed of overoxidized poly(3,4-ethylenedioxythiophene)(OPEDOT),gold nanoparticles(Au NPs),and electrochemically reduced graphene oxide(ERGO)was prepared on a glassy carbon electr... An innovative,ternary nanocomposite composed of overoxidized poly(3,4-ethylenedioxythiophene)(OPEDOT),gold nanoparticles(Au NPs),and electrochemically reduced graphene oxide(ERGO)was prepared on a glassy carbon electrode(GCE)(OPEDOT-Au NPs-ERGO/GCE)through homogeneous chemical reactions and heterogeneous electrochemical methods.The morphology,composition,and structure of this nanocomposite were characterized by transmission electron microscopy,scanning electron microscopy,X-ray diffraction,and X-ray photoelectron spectroscopy.The electrochemical properties of the OPEDOT-Au NPs-ERGO/GCE were investigated by cyclic voltammetry using potassium ferricyanide and hexaammineruthenium(III)chloride redox probe systems.This modified electrode shows excellent electro-catalytic activity for dopamine(DA)and uric acid(UA)under physiological p H conditions,but inhibits the oxidation of ascorbic acid(AA).Linear voltammetric responses were obtained when DA concentrations of approximately 4.0-100μM and UA concentrations of approximately 20-100μM were used.The detection limits(S/N=3)for DA and UA were 1.0 and 5.0μM,respectively,under physiological conditions and in the presence of 1.0 m M of AA.This developed method was applied to the simultaneous detection of DA and UA in human urine,where satisfactory recoveries from 96.7%to 105.0%were observed.This work demonstrates that the developed OPEDOT-Au NPs-ERGO ternary nanocomposite,with its excellent ion-selectivity and electro-catalytic activity,is a promising candidate for the simultaneous detection of DA and UA in the presence of AA in physiological and pathological studies. 展开更多
关键词 GRAPHENE Poly(3 4-ethylenedioxythiophene) OVEROXIDATION DOPAMINE Uric acid ascorbic acid
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Square wave voltammetric quantification of folic acid,uric acid and ascorbic acid in biological matrix 被引量:1
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作者 Majid Arvand Akram Pourhabib Masoud Giahi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第2期110-117,共8页
Nowadays, modified electrodes with metal nanoparticles have appeared as an alternative for the electroanalysis of various compounds. In this study, gold nanoparticles(GNPs) were chosen as interesting metal nanoparticl... Nowadays, modified electrodes with metal nanoparticles have appeared as an alternative for the electroanalysis of various compounds. In this study, gold nanoparticles(GNPs) were chosen as interesting metal nanoparticles for modifying carbon paste electrode(CPE). GNPs and the gold nanoparticles-modified carbon paste electrode(GNPs/CPE) were characterized by UV–Vis spectroscopy, transmission electron microscopy(TEM) and scanning electron microscopy(SEM). GNPs/CPE as a simple and sensitive electrode was used to study three important biological molecules: folic acid(FA), uric acid(UA) and ascorbic acid(AA). Square wave voltammetry(SWV) was used as an accurate technique for quantitative measurements. A good linear relation was observed between anodic peak current(ipa) and FA(5.2 × 10^(-6)– 2.5 × 10^(-5)M), UA(1.2 × 10^(-6)– 2.1 × 10^(-5)M) and AA(1.2 × 10^(-6)– 2.5 × 10^(-5)M) concentrations in simultaneous determination of these molecules. 展开更多
关键词 ascorbic acid Folic acid gold nanoparticles-modified carbon paste ELECTRODE Simultaneous determination Uric acid
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Polyphenols,Ascorbic Acid and Carotenoids Contents and Antioxidant Properties of Habanero Pepper(Capsicum chinense)Fruit 被引量:2
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作者 Maira Rubi Segura Campos Karen Ramírez Gómez +1 位作者 Yolanda Moguel Ordonez David Betancur Ancona 《Food and Nutrition Sciences》 2013年第8期47-54,共8页
Their high bioactive compounds content and importance as dietary antioxidants has increased interest in Capsicum fruit. The fruit of seven Capsicum chinense Jacq. var. habanero genotypes grown in Yucatan, Mexico, were... Their high bioactive compounds content and importance as dietary antioxidants has increased interest in Capsicum fruit. The fruit of seven Capsicum chinense Jacq. var. habanero genotypes grown in Yucatan, Mexico, were analyzed to quantify their phenolic compounds, carotenoids and ascorbic acid contents, and to measure their free radical scavenging (ABTS assay) and antioxidant activities (β-carotene/linoleic acid assay). Phenolics (20.54 to 20.75 mg/100 g sample), carotenoids (1.00 to 1.26 mg/100 g sample) and ascorbic acid contents (187.24 to 281.73 mg/100 g sample) varied between genotypes. Trolox equivalent antioxidant capacity (TEAC) ranged from 1.55 to 3.23 mM/mg sample. During the 120-min decolorization trial, antioxidant capacity decreased over time in the studied genotypes. Values ranged from 36%to 57% β-carotene bleaching during the first 30 minutes. Fruit from all seven studied genotypes are good antioxidant sources and hold promise as natural ingredients in functional foods. 展开更多
关键词 Capsicum chinense Jacq Phenolic Compounds Carotenoids Content ascorbic acid Content Antioxidant Activities
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Study on NO_2 absorption by ascorbic acid and various chemicals
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作者 李伟 吴成志 +2 位作者 方和良 施耀 雷乐成 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第1期38-42,共5页
关键词 NO2 ABSORPTION Rate constant ascorbic acid
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Selective Detection of Dopamine in the Presence of Ascorbic Acid at Poly (m-Aminobenzene Sulfonic Acid) 被引量:1
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作者 Gamze Erdogdu Mehmet Mutluhan Mutlu 《American Journal of Analytical Chemistry》 2011年第5期582-588,共7页
Poly (m-aminobenzene sulfonic acid, m-ABSA) films were electrochemically prepared by cyclic voltammetry (CV) in 0.1 mol L–1 KCl solution. The dopamine (DA) selectivity of polymeric electrodes prepared at the differen... Poly (m-aminobenzene sulfonic acid, m-ABSA) films were electrochemically prepared by cyclic voltammetry (CV) in 0.1 mol L–1 KCl solution. The dopamine (DA) selectivity of polymeric electrodes prepared at the different thicknesses was examined in the presence of ascorbic acid (AA). The results showed that the modified electrode showed an excellent electrocatalytical effect towards oxidation of dopamine (DA) and ascorbic acid (AA). Electrostatic interaction between the negatively charged poly(m-ABSA) film and either cationic DA species or anionic AA species favorably contributed to the redox response of DA and AA. Moreover, the regular and repetitive responses for dopamine were obtained even in the presence of the some interfering substances such as ascorbic acid, NaCl, NaClO4, Na2SO4 ,NaNO3 and KCl. 展开更多
关键词 Poly(m-Aminobenzene Sulfonic acid) DOPAMINE ascorbic acid
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Cu^(2+)-Catalyzed Oscillatory Oxidation of Ascorbic Acid by O_2 Flow
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作者 He Xing LI*, Ye Ping XU, Ming Hui WANG Department of Chemistry, Shanghai Normal University, Shanghai 200234 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第8期715-718,共4页
A novel heterogeneous oscillator, the Cu2+-catalyzed oscillatory oxidation of ascorbic acid (Vitamin C) in aqueous solution by O2 flow was reported. Both the potential oscillations on Pt-electrode corresponding to [Cu... A novel heterogeneous oscillator, the Cu2+-catalyzed oscillatory oxidation of ascorbic acid (Vitamin C) in aqueous solution by O2 flow was reported. Both the potential oscillations on Pt-electrode corresponding to [Cu2+] and the absorbance oscillations at (=260 nm corresponding to [ascorbic acid] were observed. Oscillations in the completely homogeneous system were also observed. Effects of several factors on the oscillations were investigated. 展开更多
关键词 Organic-O2 oscillators heterogeneous and homogeneous oscillators CU2+ O2 flow ascorbic acid.
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Higher doses of ascorbic acid may have the potential to promote nutrient delivery via intestinal paracellular absorption
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作者 Ivana Roosevelt Sequeira 《World Journal of Gastroenterology》 SCIE CAS 2021年第40期6750-6756,共7页
The significance of plasma ascorbic acid(AA)is underscored by its enzymatic and antioxidant properties as well as involvement in many aspects of health including the synthesis of biomolecules during acute illness,trau... The significance of plasma ascorbic acid(AA)is underscored by its enzymatic and antioxidant properties as well as involvement in many aspects of health including the synthesis of biomolecules during acute illness,trauma and chronic health conditions.Dietary intake supports maintenance of optimal levels with supplementation at higher doses more likely pursued.Transient increased intestinal paracellular permeability following high dose AA may be utilised to enhance delivery of other micronutrients across the intestinal lumen.The potential mechanism following dietary intake however needs further study but may provide an avenue to increase small intestinal nutrient co transport and absorption,including in acute and chronic illness. 展开更多
关键词 ASPIRIN ascorbic acid Paracellular permeability Antioxidant Lactulose mannitol test
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Ascorbic acid induces Ca2+-dependent necrosis mediated by reactive oxygen species in colorectal cancer cells
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作者 WANG Chang-xi YU Jie +2 位作者 ZHONG Bing-ling LU Jin-Jian CHEN Xiu-ping 《中国药理学与毒理学杂志》 CAS 北大核心 2019年第9期697-697,共1页
OBJECTIVE Ascorbic acid(AA),commonly known as vitamin C,is a small molecular widely distributed in in food and traditional herbs.Recently,there are some literatures reported that high concentration AA could selectivel... OBJECTIVE Ascorbic acid(AA),commonly known as vitamin C,is a small molecular widely distributed in in food and traditional herbs.Recently,there are some literatures reported that high concentration AA could selectively kill the cancer cells but not the normal cells.This study was designed to explore the underlying mechanisms.METHODS Colorectal cancer line cells were cultured and treated with AA.The cytotoxic,intracellular ATP level,reactive oxygen species,calcium,were determined with commercial kits and fluorescent probes.RESULTS High concentration of AA induced cell death in HCT116 and HT29 colorectal cancer cells in concentration-and time-dependent manner.AA treat⁃ment induced ATP decrease,LDH release,cell swollen and loss of plasma membrane integrity.Pharmacological inhibi⁃tors for apoptosis,necroptosis,autophagy,pyroptosis and oncosis showed no effect on AA-induced cell death.Further⁃more,ROS level increase and intracellular calcium(Ca2+)accumulation were observed after AA treatment.ROS scavenger N-acetyl cysteine(NAC),intracellular calcium chelator BAPTA-AM and intracellular calcium inhibitor 2-aminoethoxy⁃diphenyl borate(2-APB)could attenuate the cell death induced by AA.NAC could attenuate both ROS increase and intracellular Ca2+accumulation induced by AA,while BAPTA-AM could only attenuate intracellular Ca2+accumulation.In addition,high concentration AA induced mitochondrial damage and mitochondrial ROS generation.CONCLUSION AA induces Ca2+-dependent programed necrosis mediated by ROS.Our study provided new insights into high concentration AA induced cell death in human colon cancer cells. 展开更多
关键词 ascorbic acid ROS CA2+ programed necrosis
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Preparation of Mouse Embryonic Stem Cells and Cardiomyocyte Differentiation Induced with Retinoic Acid and Ascorbic Acid
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作者 Zhao Xun-wu Zheng Peng +3 位作者 Huang Zhi-jun Zeng Yue Adegoke E O Zhang Gui-xue 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期62-66,共5页
The experiment was designed to study effects of retinoic acid and ascorbic acid on differentiation of mouse embryonic stem cells to cardiomyocytes. Embryonic bodies(EB) were developed from m ESC in suspension culture,... The experiment was designed to study effects of retinoic acid and ascorbic acid on differentiation of mouse embryonic stem cells to cardiomyocytes. Embryonic bodies(EB) were developed from m ESC in suspension culture, different levels of concentration of retinoic acid and ascorbic acid were used to determine the optimal conditions for EB formation. The results showed that the optimal concentrations were 10-9 mol · L-1 and 0.1 mg · m L-1 for retinoic acid and ascorbic acids, respectively. 50% of EB which was significantly(p<0.05) different from the control group developed to cardiomyocytes. In conclusion, retinoic acid and ascorbic acid had strong ability to promote cardiomyocyte differentiation of mouse embryonic stem cells. 10-9 mol · L-1 retinoic acid and 0.10 mg · m L-1 ascorbic acids were recommended to induce differentiation of mouse ES cells toward cardiomyocytes. 展开更多
关键词 embryonic stem cell DIFFERENTIATION retinoic acid ascorbic acid
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An improved sensitivity non-enzymatic ascorbic acid sensor based on a Ag_2O nanowire modified Ag electrode
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作者 匡延松 何家洪 +1 位作者 高志强 宋仲容 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第2期33-36,共4页
In this paper, the Ag2O nanowires had been prepared and applied for the fabrication of ascorbic acid sensors with high enhanced sensitivity by using self-assembly technology. The structures and morphologies of Ag2O na... In this paper, the Ag2O nanowires had been prepared and applied for the fabrication of ascorbic acid sensors with high enhanced sensitivity by using self-assembly technology. The structures and morphologies of Ag2O nanowires were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The direct electrocatalytic oxidation of ascorbic acid in alkaline medium at Ag2O nanowires modified electrodes had been investigated in detail and the condition for determination of ascorbic acid was optimized, such as support-electrolyte, pH and scan speed. The oxidation peak current changed linearly with the concentration of ascorbic acid over the range from 2.0×10-8 mol/L to 1.0 mmol/L, and the detection limit can reach 1.0×10-8mol/L. Compared to a bare Ag electrode, a substantial decrease in the overvoltage of the ascorbic acid oxidation was observed at the Ag nanowires electrodes with oxidation starting at ca. 0.7V vs. Ag/AgCl (saturated KCl). The Ag2O nanowires modified electrode allows highly sensitive, low working potential, stable, and fast amperometric sensing of ascorbic acid, thus is promising for the future development of non-enzymatic ascorbic acid sensors. 展开更多
关键词 ascorbic acid Ag2O nanowires eletrocatalysis SENSOR
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Studies on Zeolite Modified Electrode(Ⅰ)─Ascorbic Acid Sensor Based on Carbon Paste Electrode Containing Fe(Ⅲ)Y Zeolite
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作者 Ming Zhu ZOU Hong Ding XU +1 位作者 Jie LU Qin Hua Ru (a Department of Chemistry, Jilin University, Changchun 130023 b Department of Chemistry, the North-East Normal University, Changchun 130022) (To whom correspondence should be addressed ) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第3期247-250,共4页
A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accu... A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accuracy wee investigated. The experimental results indicate that the analytical performance of the sensor is satisfactory. 展开更多
关键词 ascorbic acid Sensor Based on Carbon Paste Electrode Containing Fe Y Zeolite Studies on Zeolite Modified Electrode
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Ascorbic acid and low-volume polyethylene glycol for bowel preparation prior to colonoscopy:A meta-analysis
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作者 Jonathan D Godfrey Robert E Clark +4 位作者 Abhishek Choudhary Imran Ashraf Michelle L Matteson Srinivas R Puli Matthew L Bechtold 《World Journal of Meta-Analysis》 2013年第1期10-15,共6页
AIM: To evaluate the benefits of low-volume polyethylene glycol(PEG) with ascorbic acid compared to fulldose PEG for colonoscopy preparation. METHODS: MEDLINE, Cochrane Central Register of Controlled Trials and Databa... AIM: To evaluate the benefits of low-volume polyethylene glycol(PEG) with ascorbic acid compared to fulldose PEG for colonoscopy preparation. METHODS: MEDLINE, Cochrane Central Register of Controlled Trials and Database of Systematic Reviews, CINAHL, Pub Med, and recent abstracts from major conferences were searched(January 2012). Only randomized-controlled trials on adult subjects comparing lowvolume PEG(2 L) with ascorbic acid vs full-dose PEG(3 or 4 L) were included. Meta-analysis for the efficacy of low-volume PEG with ascorbic acid and full-dose PEG were analyzed by calculating pooled estimates of number of satisfactory bowel preparations as well as adverse patient events(abdominal pain, nausea, vomiting). Separate analyses were performed for each main outcome by using OR with fixed and random effects models. Heterogeneity was assessed by calculating the I2 measure of inconsistency. Rev Man 5.1 was utilized for statistical analysis.RESULTS: The initial search identified 242 articles and trials. Nine studies(n = 2911) met the inclusion criteria and were analyzed for this meta-analysis with mean age range from 53.0 to 59.6 years. All studies were randomized controlled trials on adult patients comparing large-volume PEG solutions(3 or 4 L) with low-volume PEG solutions and ascorbic acid. No statistically significant difference was noted between lowvolume PEG with ascorbic acid and full-dose PEG for number of satisfactory bowel preparations(OR 1.07, 95%CI: 0.86-1.33, P = 0.56). No statistically significant difference was noted between low-volume PEG with ascorbic acid and full-dose PEG for abdominal pain(OR 1.09, 95%CI: 0.81-1.48, P = 0.56), nausea(OR 0.70, 95%CI: 0.49-1.00, P = 0.05), or vomiting(OR 0.99, 95%CI: 0.78-1.26, P = 0.95). No publication bias was noted.CONCLUSION: Low-volume PEG with the addition of ascorbic acid demonstrates no statistically significant difference to full-dose PEG for satisfactory bowel preparation and side-effects. 展开更多
关键词 Polyethylene glycol ascorbic acid COLONOSCOPY META-ANALYSIS Bowel preparation
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EFFECT OF ASCORBIC ACID ON ISCHEMIA-REPERFUSION ARRHYTHMIAS IN ISOLATED GUINEA PIG RIGHT VENTRICULAR WALL
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作者 刘书勤 袁秉祥 李增利 《Academic Journal of Xi'an Jiaotong University》 2000年第1期19-22,封三,共5页
关键词 ascorbic acid ISCHEMIA-REPERFUSION ARRHYTHMIA ELECTROPHYSIOLOGY
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Topical Application of Ascorbic Acid Solution as an Adjunctive Method of Periodontal Therapy among Wet Snuff Users after Prosthodontics Therapy
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作者 Mohammed M. A. Abdullah Al-Abdaly Ali Saleh Alghamdi +1 位作者 Ahmad Hassan Alshehri Faris Ahmed Abdullah Al Nasser 《Open Journal of Stomatology》 2021年第3期119-132,共14页
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">During ... <b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">During several years, ascorbic acid (vitamin C) played a significant role in the health of periodontal tissues.</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">The goals of prosthodontics management are to restore the missing teeth, provide the loss of teeth functions, and establish acceptable dental esthetics, and there are some evidence</span><span style="font-family:Verdana;">s </span><span style="font-family:Verdana;">reveal</span><span style="font-family:Verdana;">ing</span><span style="font-family:Verdana;"> the passive effects of snuff</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">on the results of prosthodontics and periodontal treatment</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> so the present study </span><span style="font-family:Verdana;">is </span><span style="font-family:Verdana;">performed to evaluate the outcomes of topical application of ascorbic acid solution as an adjunctive method of periodontal therapy among wet sniff users after prosthodontics therapy.</span><span style="font-family:Verdana;"> </span><b><span style="font-family:Verdana;">Methods:</span></b><b><span style="font-family:Verdana;"> </span></b><span style="font-family:Verdana;">The clinical situation was evaluated in 150 moderate periodontitis patients after conventional periodontal and prosthodontics therapy. They were selected from outpatient clinics, college of dentistry, King Khalid University, and from some hospitals Ministry of Health in Tabuk, Jazan and Aseer regions. The study was conducted from September 2020 to December 2020. The time of post-treatment assessment was one year. The study was included 50 patients </span><span style="font-family:Verdana;">who </span><span style="font-family:Verdana;">don</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">t use wet snuff as a group I (GI) (control group),  50 patients wet snuff users as group II (GII), and 50 patients wet snuff users were treated with topical application of ascorbic acid solution as group III (GIII). The participants were aged over 20 years, with a mean age of 35 years. The duration of using wet snuff was at least one year. Plaque index (PLI), gingival index (GI), clinical attachment loss (CAL) were recorded at baseline (first visit), then after 4</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">weeks</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">(second visit) and after 6</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">weeks</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">(third visit) of conventional periodontal therapy and topical application of ascorbic acid solution. Statistical analysis was done using ANOVA test and paired t-test. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">According to statistical analysis, there was the inclination of decrease in the mean and </span><span style="font-family:Verdana;">standard deviation of plaque index (PLI) from 2.8</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">1.4 to 2.5</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.51, and 2.</span><span style="font-family:Verdana;">7</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.33 in group II, and decrease from 2.7</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.34 to 2.5</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.23 and 2.6</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.65 in group III. Similarly in the gingival index (GI)</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> there was a decrease in the mean and standard deviation from 2.8</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.52 to 2.3</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.62 and 2.5</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.51 in group II and a decrease from 2.5</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.8 to 2.3</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.58 and 2.4</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.47 in group III. Moreover, there was a decrease in the mean and standard deviation of clinical attachment loss (CAL) from 4.5</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.26 to 3.9</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.83 and 4.2</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.83 in group II and from 4.2</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.31 to 3.8</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.46 and 3.8</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.31 in group III;less than group I without significance differences (p > 0. 05) in all study groups at baseline and after 4</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">weeks, and 6</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">weeks of follow up except CAL. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The results of our study displayed that periodontal parameters vary among wet snuff users after topical application of ascorbic acid solution as an adjunctive method of periodontal therapy</span> 展开更多
关键词 An Adjunctive Periodontal Therapy ascorbic acid Solution Prosthodontics Therapy Wet Snuff
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Effect of Ascorbic Acid Supplementation on Liver Function Tests in Hepatitis C Patients
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作者 Iffat Nayila 《Open Journal of Internal Medicine》 2020年第3期263-279,共17页
An isolated liver function test is of little role in selection of liver disease because many harmful liver diseases may be correlated with normal levels of LFT’s. The outline of enzyme abnormalities in the perspectiv... An isolated liver function test is of little role in selection of liver disease because many harmful liver diseases may be correlated with normal levels of LFT’s. The outline of enzyme abnormalities in the perspective of patient’s commonly observed symptoms and laboratory data might be helpful in directing the subsequent diagnosis of liver diseases. Liver Function Tests (LFTs) are most generally used screening blood tests for assessment of different liver diseases and these tests provide a lot of evidence for disease processes whether for the purpose of investigation of supposed liver disease or help in observing the progress of disease action or simply by blood investigation. The evaluation of different liver enzymes simply gives diagnostic information on basic level whether patient’s principal disorder is actually hepatitis or cholestasis in source. However, it is necessary in various cases to evaluate LFTs with knowledge of liver functioning enzyme fractions. The objective of this study was to explore the effects of ascorbic acid supplementation on serum liver function tests in Hepatitis C patients. A total of 100 hepatitis C patients were selected randomly. 50 were given ascorbic acid supplementation for one month along with anti HCV treatment. The other 50 HCV patients took their normal anti HCV treatment without intake of ascorbic acid supplementation, and serum ascorbic acid level and liver function test parameters were observed before and after intake of ascorbic acid in both groups. The liver function parameters determined were aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), serum total bilirubin, direct bilirubin, indirect bilirubin and serum protein (total protein, albumin, globulin and A/G ratio). These parameters along with serum ascorbic acid were measured before and 30 days after vitamin C supplementation. Various abnormally elevated LFTs were also improved more rapidly when compared to other group which was not given ascorbic acid supplements for the period of one month. There was a significant change in levels of some liver function parameters before and after intake of ascorbic acid supplementation, and various abnormally elevated LFTs were also improved when compared to other group which was not given ascorbic acid supplements for the period of one month. The effect of Vitamin C supplementation was more marked on serum aminotransferase levels. After one-month use of ascorbic acid, serum alanine aminotransferase (p < 0.042) and serum aspartate aminotransferase (p < 0.000) levels were significantly decreased in hepatitis C patient group. In HCV group with ascorbic acid supplementation, serum total bilirubin (p < 0.046) and serum direct bilirubin (p < 0.048) were found to be less than the pre values when compared to HCV group without ascorbic acid supplementation. It was also observed that some of protein values were suggestively improved after intake of ascorbic acid supplementation. 展开更多
关键词 Supplementation ascorbic acid Liver Function Tests Alanine Aminotransferase Aspartate Aminotransferase SIGNIFICANT DIAGNOSES Alkaline Phosphatase
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